DIAPER HAVING EXTENSIBLE TRANSVERSE BARRIER

Abstract: A disposable diaper having a transverse barrier. The transverse barrier is extensible in order to accommodate the presence of fecal material deposited in the rear portion of the diaper. When the transverse barrier is extended, the volume of the fecal material is accommodated without breaching the transverse barrier and allowing smearing of fecal material in the front portion of the diaper onto the wearer's skin.

Description: DIAPER HAVING EXTENSIBLE TRANSVERSE BARRIER FIELD OF THE INVENTION The present invention relates to disposable absorbent articles, and more particularly to disposable absorbent articles, such as diapers, having a transverse partition which both minimizes the migration of fecal material deposited on the disposable absorbent article, and which accommodates the receipt and migration of fecal material. BACKGROUND OF THE INVENTION Disposable absorbent articles, such as diapers, are well known in the art. Disposable absorbent articles retain and absorb body exudates, such as urine and fecal material deposited thereon. Significant advances have been made in the art relative to absorbing and retaining urine deposits. For example, disposable absorbent articles seldom leak and may be relatively thin due to the incorporation of absorbent gelling materials. However, fewer attempts have been made in the art to handle deposits of fecal material in disposable absorbent articles. Fecal material has the undesirable proclivities of smearing onto the wearer's skin, causing epidermal irritation and complicating the task of cleaning the wearer when the soiled diaper or other disposable absorbent article is removed. To overcome these proclivities, certain attempts have been made in the art to isolate the fecal material from the skin of the wearer. Such attempts generally provide a void or hole into which the fecal material is deposited and retained (hopefully), so that the location of the fecal material is limited to the position of the void or hole. Examples of such attempts are found in U.S. Patent 4,662,877 issued May 5, 1987, to Williams; U.S. Patent 4,892,536 issued January 9, 1990, to DesMarais et al.; U.S. Patent 4,968,312 issued November 6, 1990, to Khan; U.S. Patent 4,990,147 issued February 5, 1991 , to Freeland; U.S. Patent 5,062,840 issued November 5, 1991 , to Holt et al. Other attempts have been made in the art to provide cups which attempt to circumscribe the anal opening, the genitalia, or both in an attempt to isolate these regions of the wearer's body. These attempts can be uncomfortable for the wearer and require precise positioning of the cup. In still another attempt, resilient barriers extending transversely or longitudinally have been placed below the topsheet of the diaper. But this arrangement suffers from the drawback that fecal material deposited on the topsheet is above the barrier, can still migrate and still cause the aforementioned problems. This arrangement simply does not provide the abrupt discontinuity necessary to obstruct migration of fecal material deposited on the topsheet of the diaper. Furthermore, such an arrangement may even be ineffective in preventing excessive transverse migration of the fecal material. A barrier disposed below the topsheet cannot be easily joined to longitudinally extending barrier leg cuffs, which, as are well known in the art, minimize leakage from the diaper. Thus, fecal material which is channeled towards transverse migration by the barrier may be transported to the perimeter of the diaper and breach the perimeter, causing leakage. It has been found that the transverse barrier is preferably rearwardly angled, i.e., angled towards the rear waist margin of the diaper. A transverse partition which makes an acute angle of 45 to 85 degrees with the plane of the topsheet has been found to be particularly effective, as disclosed in commonly assigned U.S. Patent Application Serial No. 08/664,603, filed June 18, 1996, Issue Batch No. J78, the disclosure of which is incorporated herein by reference. However, Applicants have further found that merely providing a transverse barrier with a rearward angle does not necessarily provide the optimum arrangement for accommodating fecal material deposited on the diaper. As the fecal material migrates towards the front of the diaper, it is captured, or retained in position by the transverse barrier. As additional fecal material migrates forward, the transverse barrier preferably expands, to accommodate the presence and volume of the fecal material. If the transverse barrier does not expand, a damming effect may occur. The volume of the damming fecal material is constant. If the volume is too great, the fecal material may build up and breach the top of the transverse barrier. If the fecal material crosses the transverse barrier, it typically smears the wearer's genitals - making cleanup more difficult. Accordingly, it is an object of the present invention to provide a disposable absorbent article, such as a diaper, having a transverse barrier which limits the migration of fecal material. It is further an object of this invention to provide a disposable absorbent article having such a transverse barrier which accommodates the volume of fecal material deposited on the diaper and which contacts the transverse barrier. It is finally an object of the present invention to provide a disposable absorbent article having a transverse barrier which defines a volume, which volume can increase to accommodate fecal material therein. BRIEF SUMMARY OF THE INVENTION The present invention comprises a disposable absorbent article, such as a diaper. The article has a longitudinal axis and a lateral axis orthogonal thereto. The longitudinal and lateral axes define the plane of the diaper. The diaper has a Z-direction orthogonal to the plane of the diaper and orthogonal to the plane defined by the longitudinal and lateral axes of the diaper. The diaper further has a periphery defined by a front waist margin, a rear waist margin, and two longitudinal side margins connecting the front and rear waist margins. The diaper further comprises a liquid pervious topsheet, a liquid impervious backsheet joined to the topsheet, an absorbent core intermediate the topsheet and the backsheet, and a pair of upstanding barrier leg cuffs. Each barrier leg cuff extends outwardly from a proximal end joined to the topsheet to a distal end spaced from the proximal end. The barrier leg cuffs are generally longitudinally oriented. The diaper further comprises a laterally oriented transverse barrier. The transverse barrier is joined to the topsheet at a proximal end and extends outwardly therefrom. The transverse barrier is further joined to each of the barrier leg cuffs. The diaper has a fecal material containing volume. The fecal material containing volume is defined by and contained within the proximal and distal ends of the transverse barrier and the barrier leg cuffs. The fecal material containing volume is increasable upon the deposition of fecal material therein and which intercepts the transverse barrier. The transverse barrier may be extensible, whereby the fecal material containing volume is increasable upon the receipt of fecal material therein. Furthermore, the transverse barrier may be elastically extensible. The transverse barrier may comprise an elastic panel. The panel may be elastically extensible in the longitudinal direction, the lateral direction, or bilaterally extensible. Alternatively, the elasticity may be provided by a series of elastic strands. In yet another embodiment, the extensibility need not be elastic, but may, for example, be provided by pleats having releasable frangible bonds. The bonds are broken upon receipt of or pressure due to the presence of fecal material. Any such embodiment is sufficient, so long as the fecal material containing volume is increasable upon receipt of fecal material therein, and preferably which does increase in response to the presence of fecal material contacting the transverse barrier. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a top plan view of the disposable absorbent article according to the present invention shown partially in cutaway and having no elastic induced contraction. Figure 2 is an offset vertical sectional view taken along line 2-2 of Fig. 1. Figure 3 is a fragmentary instant vertical sectional view taken along line 3-3 of Fig. 1. Figure 4 is a fragmentary instant vertical sectional view, similar to that of Fig. 3 illustrating the effect of the presence of fecal material within the fecal material containing volume. Figure 5 is a schematic perspective view of the portion of the diaper shown in Fig. 3, illustrating the fecal material containing volume. Figure 6 is a frontal elevational view of a transverse partition having an extensible central tri-section and inextensible outboard trisections. Figure 7 is a frontal elevational view of a transverse partition having an extensible central tri-section which tapers to a lesser width as the proximal edge of the transverse partition is approached. 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 liner. A preferred embodiment of an absorbent article of the present invention is the unitary disposable absorbent article, diaper 20, shown in Figure 1. As used herein, the term "diaper" refers to an absorbent article generally worn by infants or incontinent persons 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 incontinent briefs, incontinent undergarments, diaper holders and liners, certain feminine hygiene garments, and the like. Figure 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. As shown in Figure 1 , the diaper 20 preferably comprises a liquid pervious topsheet 24; a liquid impervious backsheet 26 joined with the topsheet 24; an absorbent core 28 positioned between the topsheet 24 and the backsheet 26; elasticized barrier leg cuffs 32; a fastening system 36 generally multiply designated as 36; and an upstanding transverse partition 38. The topsheet 24 of the diaper 20 has an outwardly oriented body facing surface which faces (and usually contacts) the wearer while the diaper 20 is in use and a core facing surface opposed to the body facing surface. The body facing surface of the topsheet 24 of the diaper 20 comprises that portion of the diaper 20 which is positioned adjacent the wearer's body during use (i.e., the inner surface generally is formed by both at least a portion of the topsheet 24 and other components joined to the topsheet 24). The diaper 20 further has a first waist region 31 oriented towards the front of the wearer while the diaper 20 is in use, a second waist region 33 longitudinally opposite the first waist region 31 , a crotch region 35 positioned between the first waist region 31 and the second waist region 33, and a periphery which is defined by the outer edges of the diaper 20. The diaper 20 has a longitudinal centerline L-L which divides the diaper 20 into left and right halves, and which divides the standing wearer into left and right body halves. The diaper 20 further comprises a transverse centerline T-T orthogonal to the longitudinal centerline L-L which divides the diaper 20 into a front portion and a rear portion. The transverse centerline T-T is midway between the front and rear longitudinal extremities of the diaper chassis. Orthogonal to the mutually perpendicular longitudinal centerline L-L and transverse centerline T-T, is a Z-direction axis, which extends outwardly from the plane of the diaper 20. A component of the diaper 20 is considered to be transversely oriented, and hence "transverse" if such component forms an angle of + 45 degrees or less with the transverse centerline T-T. Similarly, a component is considered to be longitudinally oriented, and hence "longitudinal" if such component forms an angle of + 45 degrees or less with the longitudinal centerline L-L. Figure 1 shows a preferred embodiment of the diaper 20 in which the topsheet 24 and the backsheet 26 have length and width dimensions generally larger than those of the absorbent core 28. The topsheet 24 and the backsheet 26 extend beyond the edges of the absorbent core 28 to thereby form the periphery of the diaper 20. While the topsheet 24, the backsheet 26, and the absorbent core 28 may be assembled in a variety of well known configurations, preferred diaper configurations are described generally in U.S. Patent 3,860,003 entitled "Contractable Side Portions for Disposable Diaper" which issued to Kenneth B. Buell on January 14, 1975, which is incorporated herein by reference. The absorbent core 28 may be any absorbent means which is generally compressible, conformable, non-irritating to the wearer's skin, and capable of absorbing and retaining liquids such as urine and other certain body exudates. As shown in Figure 1 , the absorbent core 28 has a garment surface, a body surface, side edges, and waist edges. The absorbent core 28 may be manufactured in a wide variety of sizes and shapes (e.g., rectangular, hourglass, "T"-shaped, asymmetric, etc.) and from 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 airfelt. Examples of other suitable absorbent materials include creped cellulose wadding; meltblown polymers including coform; 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 equivalent material or combinations of materials. The configuration and construction of the absorbent core 28 may also be varied (e.g., the absorbent core 28 may have varying caliper zones, a hydrophilic gradient, a superabsorbent gradient, or lower average density and lower average basis weight acquisition zones; or may comprise one or more layers or structures). The total absorbent capacity of the absorbent core 28 should, however, be compatible with the design loading and the intended use of the diaper 20. Further, the size and absorbent capacity of the absorbent core 28 may be varied to accommodate wearers ranging from infants through adults. Exemplary absorbent structures for use as the absorbent core 28 are described in U.S. Patent 4,610,678 entitled "High-Density Absorbent Structures" issued to Weisman et al. on September 9, 1986; U.S. Patent 4,673,402 entitled "Absorbent Articles With Dual-Layered Cores" issued to Weisman et al. on June 16, 1987; U.S. Patent 4,888,231 entitled "Absorbent Core Having A Dusting Layer" issued to Angstadt on December 19, 1989; and U.S. Patent 4,834,735, entitled "High Density Absorbent Members Having Lower Density and Lower Basis Weight Acquisition Zones", issued to Alemany et al. on May 30, 1989. Each of these patents are incorporated herein by reference. The backsheet 26 is positioned adjacent the garment surface of the absorbent core 28 and is preferably joined thereto by attachment means (not shown) such as those well known in the art. For example, the backsheet 26 may be secured to the absorbent core 28 by a uniform continuous layer of adhesive, a patterned layer of adhesive, or an array of separate lines, spirals, or spots of adhesive. Adhesives which have been found to be satisfactory are manufactured by H. B. Fuller Company of St. Paul, Minnesota and are marketed as HL-1258. The attachment means will preferably comprise an open pattern network of filaments of adhesive as is disclosed in U.S. Patent 4,573,986 entitled "Disposable Waste-Containment Garment", which issued to Minetola et al. on March 4, 1986, more preferably several lines of adhesive filaments swirled into a spiral pattern such as is illustrated by the apparatus and methods shown in U.S. Patent 3,911 ,173 issued to Sprague, Jr. on October 7, 1975; U.S. Patent 4,785,996 issued to Ziecker, et al. on November 22, 1978; and U.S. Patent 4,842,666 issued to Werenicz on June 27, 1989. Each of these patents are incorporated herein by reference. Alternatively, the attachment means may comprise heat bonds, pressure bonds, ultrasonic bonds, dynamic mechanical bonds, or any other suitable attachment means or combinations of these attachment means as are known in the art. The backsheet 26 is impervious to liquids (e.g., urine) and 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 26 prevents the exudates absorbed and contained in the absorbent core 28 from wetting articles which contact the diaper 20 such as bedsheets and undergarments. The backsheet 26 may thus comprise a woven or nonwoven material, polymeric films such as thermoplastic films of polyethylene or polypropylene, or composite materials such as a film-coated nonwoven material. Preferably, the backsheet 26 is a thermoplastic film having a thickness of from about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mils). Particularly preferred materials for the backsheet 26 include RR8220 blown films and RR5475 cast films as manufactured by Tredegar Industries, Inc. of Terre Haute, IN. The backsheet 26 is preferably embossed and/or matte finished to provide a more clothlike appearance. Further, the backsheet 26 may permit vapors to escape from the absorbent core 28 (i.e., breathable) while still preventing exudates from passing through the backsheet 26. The topsheet 24 is positioned adjacent the body surface of the absorbent core 28 and is preferably at least partially peripherally joined thereto and to the backsheet 26 by attachment means (not shown) such as those well known in the art. Suitable attachment means are described with respect to joining the backsheet 26 to the absorbent core 28. As used herein, the term "joined" encompasses configurations whereby an element is directly secured to the other element by affixing the element directly to the other element, and configurations whereby the element is indirectly secured to the other element by affixing the element to intermediate member(s) which in turn are affixed to the other element. In a preferred embodiment of the present invention, the topsheet 24 and the backsheet 26 are joined directly to each other in the diaper periphery and are indirectly joined together as a result of their joinder to the absorbent core 28 by suitable attachment means (not shown). The topsheet 24 is compliant, soft feeling, and non-irritating to the wearer's skin. Further, the topsheet 24 is liquid pervious permitting liquids (e.g., urine) to readily penetrate through its thickness. A suitable topsheet may be manufactured from a wide range of materials, such as porous foams; reticulated foams; apertured plastic films; or woven or nonwoven webs of natural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g., polyester, polyethylene, or polypropylene fibers), or a combination of natural and synthetic fibers. Preferably, the topsheet 24 is made of a hydrophobic material to isolate the wearer's skin from liquids contained in the absorbent core 28. There are a number of manufacturing techniques which may be used to manufacture the topsheet 24. For example, the topsheet 24 may be a nonwoven web of fibers spunbonded, carded, wet-laid, meltblown, hydroentangled, combinations of the above, or the like. A preferred topsheet is carded and thermally bonded by means well known to those skilled in the fabrics art. A preferred topsheet comprises a web of staple length polypropylene fibers such as is manufactured by Veratec, Inc., a Division of International Paper Company, of Walpole, Massachusetts under the designation P-8. The diaper 20 preferably further comprises elasticized barrier leg cuffs 32 for providing improved containment of liquids and other body exudates. Each elasticized barrier leg cuff 32 may comprise several different embodiments for reducing the leakage of body exudates from the leg regions of the diaper 20. U.S. Patent 4,909,803 entitled "Disposable Absorbent Article Having Elasticized Flaps" issued to Aziz et al. on March 20, 1990, describes a disposable diaper 20 having "stand-up" elasticized flaps (barrier leg cuffs 32) to improve the containment of the leg regions of the diaper 20. U.S. Patent 4,695,278 entitled "Absorbent Article Having Dual Cuffs" issued to Lawson on September 22, 1987, describes a disposable diaper 20 having dual cuffs including both a gasketing cuff and a barrier cuff 32. Both of these patents are incorporated herein by reference for the purpose of showing suitable exemplary constructions for the barrier leg cuffs 32. Spanning the transverse distance between the barrier leg cuffs 32 is an upstanding transverse partition 38. The transverse partition 38 is disposed on the body facing surface of the topsheet 24 and extending outwardly therefrom to present an abrupt discontinuity in the body facing surface of the topsheet 24. As illustrated, preferably the transverse partition 38 is generally straight, rectilinear, transverse and preferably parallel to the transverse centerline T-T of the diaper 20. If desired, the transverse pattern 38 may even be coincident with the transverse centerline T-T of the diaper 20. The transverse partition 38 obstructs the longitudinal migration of fecal material deposited in the rear portion of the diaper 20 towards the front portion of the diaper 20. Preferably the upstanding partition 38 connects the barrier leg cuffs 32, forming an H-shape. This arrangement is highly preferred because it prevents seepage of fecal material around the edges of the transverse partition 38 and contains the fecal material in the rear portion of the diaper 20. Referring to Figure 2, the transverse partition 38 has a proximal edge which is preferably joined to the topsheet 24, and particularly the body facing surface thereof, by adhesive, by autogeneous bonding, such as is disclosed in commonly assigned U.S. Patent 4,854,984 issued to Ball et al, which patent is incorporated herein by reference, or by other joining means, as are well known in the art. The transverse partition 38 extends outwardly from the plane of the topsheet 24 with a vector component in the Z-direction to a distal edge. It is important the transverse partition 38 be upstanding and rise above the plane of the topsheet 24 to an effective height H sufficient to present an abrupt discontinuity to obstruct the longitudinal movement of fecal material while the diaper 20 is worn. It is to be recognized that if the topsheet 24 has wrinkles, rugosities, undulations, or other deviations from planarity, these should be taken into account at the position of the transverse partition 38 when determining its effective height H. Otherwise such deviations from planarity in the topsheet 24 may diminish the effective height H of the distal edge of the partition 38 above the topsheet 24, and not sufficiently obstruct the flow of fecal material. As illustrated in Figure 3, the transverse partition 38 is preferably not orthogonal to the plane of the topsheet 24, but instead is disposed in angular relationship therewith so that the distal edge of the upstanding transverse partition 38 is oriented towards the rear portion and the rear waist margin 33 of the diaper 20. This arrangement provides the advantage that the pressure of the fecal material helps seal the transverse partition 38 against the wearer's body, minimizing the leakage of fecal material across the transverse partition 38. This arrangement further minimizes the vertical forces necessary to maintain the transverse partition 38 in contact with the body of the wearer. The transverse partition 38 has two opposed faces, a front facing surface and a rearward facing surface. The rearward facing surface forms an acute angle Z with the body facing surface of the topsheet 24. The acute angle Z is preferably from 45 to 85 degrees, and more preferably from 55 to 80 degrees, and most preferably from 65 to 75 degrees. The acute angle Z is measured in accordance with commonly assigned U.S. Patent Application Serial No. 08/664,603 filed June 18, 1996, Issue Batch No. J78, the disclosure of which is incorporated herein by reference. The transverse partition 38 may be made of a water pervious material, but is preferably made of a liquid impermeable material. The liquid impermeable material prevents (or minimizes the amount of) runny fecal material reaching the genitalia of the wearer. Nonwoven materials, such as those commonly used to form the barrier leg cuffs 32, have been found to be particularly suitable in the transverse partition 38. Other suitable materials for the transverse partition 38 include foams, formed films, etc. A suitable liquid impermeable material, particularly a liquid impermeable nonwoven material for the transverse partition 38 may be obtained from the Veratec Corporation of Walpole, Massachusetts as a hydrophobic P-8 material having a basis weight of at least 20 grams per square meter. If desired, a high basis weight spun/meltblown/spun layered web made of polypropylene or polyethylene as is available from Fiberweb Corporation under the name Eclipse could be used. Alternatively, Veratec Everspun nonwoven material may be used. A particularly preferred transverse partition 38 for female wearers allows fluids, such as urine, to permeate the barrier from the front to the rear, so that such fluid cannot sit on top of the transverse partition 38 more than necessary and irritate the skin. However, such a transverse partition 38 is preferably impervious in the direction from the rear to the front of the diaper 20, for the same reason. Such a material may be provided as a formed film made according to commonly assigned U.S. Patent 3,929,135 issued Dec. 30, 1975 to Thompson, the disclosure of which is incorporated herein by reference. For additional comfort to the wearer, a nonwoven material may be laminated to the front of the formed film. If desired, spacers (not shown) may be added to the distal edge of the transverse partition 38 to locally increase its effective height H. The spacers may be made and disposed on the transverse partition 38 according to commonly assigned U.S. Patent 5,554,142 issued September 10, 1996 to Dreier et al., the disclosure of which is incorporated herein by reference. Referring to Figure 3, the transverse barrier may be generally taut and define a flat plane as shown. In response to the presence and contact of fecal material with the transverse barrier, the transverse barrier may expand, preferably to a convex configuration as shown in Figure 4. This expansion may be thought of as an increase in the longitudinal dimension of the transverse barrier. The longitudinal dimension of the transverse barrier is measured from the proximal edge of the transverse barrier to the distal edge of the transverse barrier, coincident the longitudinal centerline L-L of the diaper 20. Of course, it is to be recognized that depending upon the volume, viscosity, and disposition of the fecal material on the topsheet 24 of the disposable absorbent article 20, the configuration of the transverse barrier as it expands to accommodate the fecal material will likely vary from that shown in Figure 4. For example, the transverse barrier may bow to a concave configuration, or otherwise generally increase in the transverse dimension. However, the important consideration is not the exact configuration of the transverse barrier in response to pressure of fecal material thereagainst. Instead, it is only important that the presence and volume of the fecal material be accommodated so that the fecal material can move forward in the longitudinal direction without building up in the Z-direction against the transverse barrier and crossing the top of the transverse barrier. By allowing the transverse barrier to expand in the forward longitudinal direction, or in the transverse direction while maintaining the seal between the proximal end of the transverse barrier and the topsheet 24, the volume of the fecal material can be accounted for without allowing it to breach the top of the transverse barrier. Referring to Figure 5, the disposable article according to the present invention may be thought of as having a fecal material containing volume 50. There is both an initial fecal material containing volume 50, i.e., that presented by the diaper 20 prior to being disposed on a wearer and soiled, and a secondary fecal material containing volume 50, i.e., that which occurs after the introduction of fecal material against the transverse barrier. The fecal material containing volume 50 is defined as follows. In cross section the fecal material containing volume 50 is generally triangular and may be a right triangle. The cross section of the fecal material containing volume 50 is defined by the proximal and distal ends of the transverse barrier, and an imaginary line from the distal end of the transverse barrier perpendicular to the outwardly facing surface of the topsheet 24. If the transverse barrier is not uniform in the transverse direction, the cross section of the fecal material containing volume 50 is measured at the longitudinal centerline L-L of the disposable article. Thus, the cross section of the fecal material containing volume 50 may be thought of as a right triangle. One leg 51 represents the imaginary line from the distal end of the transverse barrier to the outwardly oriented surface of the topsheet 24. The other leg 52 is taken from the rearwardly facing surface of the proximal end of the transverse barrier along the outwardly oriented surface of the topsheet 24 to the point where the imaginary line, discussed above, intersects the topsheet 24. The hypotenuse of the right triangle is the rearwardly facing surface of the transverse barrier. The fecal material containing volume 50 is further defined by the inwardly facing surfaces, i.e., those surfaces oriented towards the longitudinal centerline L-L, of each of the barrier leg cuffs 32. Thus, an infinite number of the aforementioned cross sections extending between the two barrier leg cuffs 32 and bounded by the transverse barrier in the topsheet 24 is defined. The fecal material containing volume 50 is the product of the transverse distance between the inwardly oriented surfaces of the barrier leg cuffs 32, and the cross sectional area discussed above. The transverse distance between the barrier leg cuffs 32 is measured coincident the outwardly facing surface of the topsheet 24. It is this fecal material containing volume 50 which is both initially defined and, which has a secondary volume greater than the initial volume in order to accommodate fecal material. Thus, it is necessary to measure two fecal material containing volumes 50. The first fecal material containing volume 50 is measured with the diaper 20 in the flat, uncontracted state of Figure 1 and prior to being disposed on the wearer. The secondary fecal material containing volume 50 is likewise measured in the flat, uncontracted state, but after the fecal material is deposited within the volume and contacts the transverse barrier. The transverse partition 38 may comprise an elastic panel. Alternatively, the transverse barrier may comprise an elastic panel and flaccid material. If flaccid material is utilized, preferably it is juxtaposed with the proximal end of the transverse barrier. The flaccid material allows for expansion of the transverse partition 38 upon even minor pressure caused by contact with the fecal material. If an elastic panel is selected for all or a portion of the transverse barrier, the elastic panel is preferably elastically extensible in the longitudinal direction, i.e., is extensible towards the front waist margin. Alternatively, in a less preferred embodiment, the elastic panel comprising the transverse barrier may be elastically extensible in the lateral direction. In still another embodiment, the elastic panel may be bilaterally extensible. The benefit of a bilaterally extensible elastic panel is its ability to provide an increase in volume 50 which volume increase is generally more independent of the wearer position and geometry of the diaper 20. A particularly preferred material is a web material exhibiting an elastic-like behavior and having molecular-level deformation in a first region and geometric deformation in a second region. Such a material may be made according to commonly assigned U.S. Patent 5,518,801 issued May 21 , 1996 to Chappell et al., the disclosure of which is incorporated herein by reference. In an alternative embodiment, as is well known in the art, extensibility may be imparted to the transverse barrier through the use of multiple elastic strands. Preferably the elastic strands are generally parallel. Suitable material for the elastic strands are well known in the art. The elastic strands may be attached to the transverse barrier by adhesive, heat shrinking, or any of the other means well known in the art. Multiple elastic strands provide the benefit over an elastic panel of providing for variable levels of extensibility, i.e., different spring rates, at different locations on the transverse partition 38. Preferably the increase in fecal material containing volume 50 upon receipt of fecal material is from about 5 to about 50 percent of its original volume. Upon receiving the fecal material, the fecal material containing volume 50 preferably has a volume of at least 30, more preferably at least 50, and most preferably at least 80 cubic centimeters. Referring to Figure 6, the transverse partition 38 may comprise three tri- sections: two outer tri-sections 60 and a central tri-section 62. The central tri- section 62 may be extensible, and more preferably may be elastically extensible. This arrangement provides the advantage that leakage over the top of the transverse partition 38 is generally minimized, due to the stiffness imparted by the inextensible outboard tri-section 60. The tri-sections need not be equal in width. Referring to Figure 7, in yet another preferred embodiment, the elastic central tri-section 62 may taper from a greater width at the distal edge of the transverse partition 38 to a vertex at the proximal edge of the transverse partition 38. Of course, it is to be recognized that the vertex of the central tri-section 62 need not be coincident the proximal edge of the central tri-section 62, but may be disposed between the proximal and distal edges of the transverse partition 38. It is to be further recognized that the extensible central tri-section 62 of the embodiment of Figure 6 need not converge to a vertex, but may merely taper from a greater width at the distal edge of the transverse partition 38 to a lesser width at the proximal edge of the transverse partition 38. The embodiment of Figure 6 provides the advantage that there is less distortion at the distal edge of the transverse partition 38 caused by movement of the barrier leg cuffs 32 of the diaper 20. Furthermore, this arrangement tends to decouple movements from the core 28 from the movements of the barrier leg cuffs 32 of the diaper 20. By decoupling movements between the core 28/leg cuffs 32 and the distal edge of the transverse partition 38, leakage when fecal material is present is reduced. It will be apparent that many variations are feasible and within the scope of the claimed invention. The elasticity may be imparted to the transverse barrier at a diagonal relative to the longitudinal and lateral directions. Elastic strands and elastic panels may be used in combination. All such variations are within the scope of the claimed invention.

Claims: What is claimed is: 1. A diaper having a longitudinal axis and a lateral axis orthogonal thereto, said longitudinal axis and said lateral axis defining the plane of said diaper, said diaper further having a Z-direction orthogonal to said plane of said diaper, said diaper having a periphery defined by a front waist margin, a rear waist margin, and two longitudinal side margins intermediate said front waist margin and said rear waist margin, said diaper comprising: a liquid pervious topsheet; a liquid impervious backsheet joined to said topsheet; an absorbent core intermediate said topsheet and said backsheet; a pair of upstanding barrier leg cuffs, each said barrier leg cuff extending outwardly from a proximal end joined to said topsheet to a distal end spaced from said proximal end, said barrier leg cuffs being generally longitudinally oriented; and a generally laterally oriented transverse barrier, said barrier being joined to said topsheet at a proximal end and extending outwardly therefrom to a distal end, said transverse barrier being joined to each of said barrier leg cuffs, said diaper having a fecal material containing volume, said fecal material containing volume being defined by and contained within the proximal and distal ends of said transverse barrier, said topsheet and said barrier leg cuffs, said fecal material containing volume being increasable upon the deposition of fecal material therein and intercepting said transverse barrier. 2. A diaper having a longitudinal axis and a lateral axis orthogonal thereto, said longitudinal axis and said lateral axis defining the plane of said diaper, said diaper further having a Z-direction orthogonal to said plane of said diaper, said diaper having a periphery defined by a front waist margin, a rear waist margin, and two longitudinal side margins intermediate said front waist margin and said rear waist margin, said diaper comprising: a liquid pervious topsheet; a liquid impervious backsheet joined to said topsheet; an absorbent core intermediate said topsheet and said backsheet; a pair of upstanding barrier leg cuffs, each said barrier leg cuff extending outwardly from a proximal end joined to said topsheet to a distal end spaced from said proximal end, said barrier leg cuffs being generally longitudinally oriented; and a generally laterally oriented transverse barrier, said barrier being joined to said topsheet at a proximal end and extending outwardly therefrom, said transverse barrier being joined to each of said barrier leg cuffs, said diaper having a fecal material containing volume, said fecal material containing volume being defined by and contained within the proximal and distal ends of said transverse barrier, said topsheet and said barrier leg cuffs, said transverse barrier being extensible, whereby said fecal material containing volume is increasable upon the receipt of fecal material therein. 3. A diaper having a longitudinal axis and a lateral axis orthogonal thereto, said longitudinal axis and said lateral axis defining the plane of said diaper, said diaper further having a Z-direction orthogonal to said plane of said diaper, said diaper having a periphery defined by a front waist margin, a rear waist margin, and two longitudinal side margins intermediate said front waist margin and said rear waist margin, said diaper comprising: a liquid pervious topsheet; a liquid impervious backsheet joined to said topsheet; an absorbent core intermediate said topsheet and said backsheet; and a generally laterally oriented transverse barrier, said barrier being joined to said topsheet at a proximal end and extending outwardly therefrom, said transverse barrier being extensible. 4. A diaper according to Claims 1 , 2, or 3 wherein said transverse barrier is elastically extensible. 5. A diaper according to Claim 4 wherein said transverse barrier is elastically extensible in said longitudinal direction. 6. A diaper according to Claims 1 , 2, 3, 4, or 5 wherein said transverse barrier comprises a zone of flaccid material. 7. A diaper according to Claim 6 wherein said zone of flaccid material is juxtaposed with said proximal end of said transverse barrier. 8. A diaper according to Claims 1 , 2, or 3 wherein said transverse barrier comprises a material exhibiting an elastic-like behavior and having a first region which undergoes a molecular-level deformation and a second region which undergoes a substantially geometric deformation. 9. A diaper according to Claims 1 , 2, 3, or 8 wherein said transverse partition comprises two outboard tri-sections and a central tri-section, said outboard tri-sections being inextensible and said central tri-section being extensible. 10. A diaper according to Claim 9 wherein said transverse partition extends from said proximal edge to a distal edge, and said central tri-section tapers from a wider width at said distal end of said transverse partition to a narrower width, said narrower width being juxtaposed with said proximal edge of said transverse partition.

Inventors: ALLEN PATRICK JAY, FREELAND MARY ELAINE, ROE DONALD CARROLL, ALLEN, PATRICK, JAY, FREELAND, MARY, ELAINE, ROE, DONALD, CARROLL
Applicants: PROCTER & GAMBLE, THE PROCTER & GAMBLE COMPANY
Application year: 1998
Main classification: A61F13
IPC codes: A61F5, A61F13