Patent Publication Number: US-2010114052-A1

Title: Absorbent article with waist seal and method of manufacturing

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to the field of absorbent articles and, more particularly, to absorbent articles such as, e.g., diapers, with waist seals and methods of manufacturing the same. 
     BACKGROUND OF THE INVENTION 
     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 minimize leakage of body exudates from between the absorbent article and the wearer. 
     One particular problem associated absorbent articles (such as, e.g., diapers) is in the containment of low viscosity fecal matter in the rear waist region of the diaper. Leakage out the rear waist region occurs because many diapers are not able to form a seal in the small of the infant&#39;s back that is tight enough to contain, e.g., low viscosity fecal matter. This problem may be more significant for infants from zero to eight months old because infants in this age range normally have a high incidence of low viscosity fecal matter. This can also be a problem for older infants/children/adults when they are ill. 
     Although diapers with elastic waists have been used, that approach does not truly address the problem of sealing against the contours of the small of the back because elastic waists just bridge the generally concave contours of the small of the back. Other solutions have been proposed that involve creating an envelope along the rear waist, with an opening facing toward the crotch region of the diaper. Another approach to this problem involves adhesively sealing the diaper to the back waist region to prevent leakage. Other proposed solutions involve creating a fluid-filled pillow in the back waist region, some by elaborate mechanism to generate a gas to fill a chamber to serve as a conformable barrier in the back waist region. Examples of some of these approaches may be described in, e.g., U.S. Pat. No. 6,458,110 B1 (Lavon et al.) and International Publication No. WO 01/21120 (Reynolds et al.) 
     While another approach includes providing additional foam material along the back waist of the diaper in an attempt to resiliently conform to the contours of the small of the infant&#39;s back (see, e.g., U.S. Patent Application Publication No. US 2006/0058767 (Zhang et al.)), there are difficulties associated with this solution. The difficulties include the limited amount of lineal material of a thicker foam (e.g., material about 1 centimeter thick or greater) that can be delivered to the diaper manufacturing line in a conventional format, such as a roll of running length material. Providing thicker materials results in rolls having excessively large diameters or significantly shorter run times—to the point at which the use of roll-fed equipment is uneconomical. 
     SUMMARY OF THE INVENTION 
     The present invention provides absorbent articles with waist seals that are formed from folded stacks, discrete segments, or pleated material arranged to provide a resiliently compressible seal that can be located at one or more desired locations within the absorbent article, such as, e.g., along a central portion of the rear waist region of a diaper. 
     The seals are preferably constructed from relatively thin materials that (through folding, stacking, pleating, etc.) can provide a resiliently compressible seal that is thick enough and appropriately shaped to conform to the wearer&#39;s anatomy well enough to provide the desired sealing. At the same, time, the continuous web material used to form the seal is preferably thin enough to be economically delivered to the manufacturing line in roll form. 
     In one aspect, the present invention provides an absorbent article adapted to fit about the waist of a wearer, the article including a central region with absorbent material, the central region further including a first end and a second end, wherein the first end and the second end are spaced at opposite ends of the central region along a longitudinal direction; a front waist region located at the first end of the central region, wherein the front waist region extends in a lateral direction across a first end of the central region, wherein the lateral direction is generally transverse to the longitudinal direction; a rear waist region located at the second end of the central region, wherein rear waist region extends in the lateral direction across the second end of the central region; and a seal occupying a portion of the rear waist region, wherein the seal includes a folded stack of three or more layers of resilient material, wherein the folded stack has a continuous length of the resilient material with two or more folds spaced apart across the rear waist region in the lateral direction and a segment of the resilient material extending in the lateral direction between each pair of folds at opposing ends of the segment. 
     In another aspect, the present invention provides an absorbent article adapted to fit about the waist of a wearer, the article including a central region with absorbent material, the central region having a first end and a second end, wherein the first end and the second end are spaced at opposite ends of the central region along a longitudinal direction; a front waist region located at the first end of the central region, wherein the front waist region extends in a lateral direction across a first end of the central region, wherein the lateral direction is generally transverse to the longitudinal direction; a rear waist region located at the second end of the central region, wherein rear waist region extends in the lateral direction across the second end of the central region; and a seal occupying a portion of the rear waist region, wherein the seal includes a continuous length of resilient material gathered in a plurality of pleats, wherein the pleats include folds separating segments of the resilient material, and wherein the segments of each pleat are oriented generally transverse to a plane defined by the longitudinal and lateral directions. 
     In another aspect, the present invention provides an absorbent article adapted to fit about the waist of a wearer, the article including a central region with absorbent material, the central region having a first end and a second end, wherein the first end and the second end are spaced at opposite ends of the central region along a longitudinal direction; a front waist region located at the first end of the central region, wherein the front waist region extends in a lateral direction across a first end of the central region, wherein the lateral direction is generally transverse to the longitudinal direction; a rear waist region located at the second end of the central region, wherein rear waist region extends in the lateral direction across the second end of the central region; and a seal occupying an inelastic portion of the rear waist region, wherein the seal includes a stack of two or more discrete segments of resilient material, wherein the two or more discrete segments have different lengths along the lateral direction. 
     In another aspect, the present invention provides a method of manufacturing an absorbent article with a waist seal. The method includes folding a continuous web of resilient material to form a folded stack of three or more layers of the resilient material; separating a portion of the folded stack from the continuous web of resilient material; and attaching the folded stack of resilient material within a rear waist region of an absorbent article. The absorbent article includes a central region with absorbent material, the central region including a first end and a second end, wherein the first end and the second end are spaced at opposite ends of the central region along a longitudinal direction; and a front waist region located at the first end of the central region, wherein the front waist region extends in a lateral direction across a first end of the central region, wherein the lateral direction is generally transverse to the longitudinal direction. The rear waist region is located at the second end of the central region, wherein the rear waist region extends in the lateral direction across the second end of the central region. The folded stack of resilient material is formed from a continuous length of the resilient material with two or more folds spaced apart across the rear waist region in the lateral direction and a segment of the resilient material extending in the lateral direction between each pair of folds at opposing ends of the segment. 
     In another aspect, the present invention provides a method of manufacturing an absorbent article with a waist seal. The method includes pleating a continuous web of resilient material to form a pleated continuous web with plurality of pleats; separating a portion of the pleated continuous web from the continuous web to form a pleated seal; and attaching the pleated seal within a rear waist region of an absorbent article. The absorbent article includes a central region with absorbent material, the central region having a first end and a second end, wherein the first end and the second end are spaced at opposite ends of the central region along a longitudinal direction; and a front waist region located at the first end of the central region, wherein the front waist region extends in a lateral direction across a first end of the central region, wherein the lateral direction is generally transverse to the longitudinal direction. The rear waist region is located at the second end of the central region, wherein the rear waist region extends in the lateral direction across the second end of the central region. The pleated seal is formed from a continuous piece of the resilient material, wherein the pleats comprise folds separating segments of the resilient material. 
     In another aspect, the present invention provides a method of manufacturing an absorbent article with a waist seal. The method includes aligning two or more continuous webs of resilient material to form a continuous stacked web of two or more layers of resilient material, wherein at least two of the two or more layers comprise different widths; 
     separating a portion of the continuous stacked web to form a stack of discrete segments of resilient material; and attaching the stack of discrete segments of resilient material within a rear waist region of an absorbent article. The absorbent article includes a central region with absorbent material, the central region having a first end and a second end, wherein the first end and the second end are spaced at opposite ends of the central region along a longitudinal direction; and a front waist region located at the first end of the central region, wherein the front waist region extends in a lateral direction across a first end of the central region, wherein the lateral direction is generally transverse to the longitudinal direction. The rear waist region is located at the second end of the central region, wherein the rear waist region extends in the lateral direction across the second end of the central region. 
     The above summary is not intended to describe each embodiment or every implementation of the present invention. Rather, a more complete understanding of the invention will become apparent and appreciated by reference to the following Detailed Description of Exemplary Embodiments and claims in view of the accompanying figures of the drawing. 
    
    
     
       BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWING 
         FIG. 1  is a top plan view of a disposable diaper with portions of the topsheet cutaway to illustrate other components of the diaper. 
         FIG. 2  is a cross-sectional sectional view of one exemplary seal in the form a folded stack taken along line  2 - 2  in  FIG. 1 . 
         FIG. 3  is a side elevational view of another exemplary seal in the form of a stack of discrete segments of resiliently compressible material. 
         FIG. 4  is plan view of the seal of  FIG. 3 . 
         FIG. 5  is a cross-sectional view of another exemplary seal including pleats of a resilient material. 
         FIG. 6  is a cross-sectional view of another exemplary seal including pleats of an elastic resilient material. 
         FIG. 7  is a block diagram of one system/method of manufacturing a waist seal according to the present invention. 
         FIG. 8  depicts a portion of one continuous web of resilient material folded for use as a waist seal. 
         FIG. 9  depicts a portion of another continuous web of resilient material that is pleated to form a pleated seal according to the present invention. 
         FIG. 10  depicts a portion of another continuous web that includes a plurality of layers stacked to form a seal in the form of a stack of discrete segments according to the present invention. 
         FIG. 11  depicts an alternative shape for a seal in the plane defined by the longitudinal and lateral directions. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     In the following detailed description of exemplary embodiments of the invention, reference is made to the accompanying figures which form a part hereof, and in which are shown, by way of illustration, specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present 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. Such absorbent articles may include, but are not limited to, diapers, training pants, incontinence briefs, diaper holders, diaper liners, and the like. The term “disposable” is used herein to describe absorbent articles that are not intended to be laundered or otherwise restored or reused as an absorbent article. 
     One embodiment of an absorbent article of the present invention is the unitary disposable diaper  20  shown in  FIG. 1 . As used herein, the term “diaper” refers to an absorbent article generally worn by infants and/or incontinent persons that is worn about the lower torso of the wearer.  FIG. 1  is a plan view of the diaper  20  of the present invention in its flat-out, uncontracted state (i.e., with any elastic induced contraction pulled out). Portions of the topsheet are cutaway to more clearly show the construction of the diaper  20 . The portion of the diaper  20  that faces or contacts the wearer (the body facing surface) is oriented towards the viewer in  FIG. 1 . The diaper  20  includes a front waist region  22 , a rear waist region  24 , and a central region  26 . The diaper  20  also defines a longitudinal direction  10  extending between the front waist region  22  and the rear waist region  24 . A lateral direction  12  is defined that is generally transverse to the longitudinal direction  10 . 
     As used herein, the “longitudinal” direction, dimension, or axis of the diaper  20  is typically aligned front to back with respect to the wearer as the disposable absorbent article is worn (i.e., extending between the front waist region  22  and the rear waist region  24  in the view of  FIG. 1 ). The “lateral” or “transverse” direction, dimension, or axis of the diaper  20  is generally transverse to the longitudinal direction  10  and is sideways aligned as the diaper  20  is worn. The “z-direction” for the diaper  20  is generally normal to the plane defined by the longitudinal and transverse directions  10  &amp;  12  and can generally be considered to extend through the thickness of the diaper  20  at a selected location. 
     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 central region  26  is disposed between the front and rear waist regions  22 ,  24  and is that part of the diaper  20  which, when worn, extends between the wearer&#39;s legs. 
     The diaper  20  preferably includes a liquid permeable topsheet  30 , a liquid impermeable backsheet  32  joined at least peripherally with the topsheet  30 , and an absorbent core  40  located between the topsheet  30  and the backsheet  32 . The absorbent core  40  has a perimeter  45  that includes front and rear laterally extending ends  45 A and  45 B. The topsheet  30 , backsheet  32  and the absorbent core  40  may be assembled in a variety of well known configurations. Examples of some potentially suitable configurations are described generally in U.S. Pat. Nos. 3,860,003 (Buell); 5,151,092 (Buell); 6,423,045 B1 (Wise et al.); 6,458,110 B1 (Lavon et al.); etc. 
     As used herein, the term “absorbent core” refers to any component(s) of the diaper  20  used for absorbing and retaining body exudates. The absorbent core  40  may have opposed major faces and may, if desired, be encased by one or more layers of tissue. The absorbent core  40  may be made from a variety of commonly used materials such as comminuted wood pulp, typically referred to as airfelt. If desired, the absorbent core  40  may contain absorbent gelling materials as is commonly used in the art. Examples of some potentially suitable absorbent cores may be described in U.S. Pat. Nos. 4,610,678 (Weisman et al.); 4,673,402 (Weisman et al.); 4,834,735 (Alemany et al.); 5,147,345 (Young et al.); 5,217,445 (Cook et al.); 5,234,423 (Alemany et al.); etc. Absorbent gelling materials made in accordance with U.S. Pat. No. Re. 32,649 (Brandt et al.) may also be suitable for use in a diaper  20  according to the present invention. 
     The diaper  20  has a body facing surface formed primarily by topsheet  30  that is positioned adjacent to the wearer&#39;s body during use. The diaper  20  also has a garment facing surface that faces away from the wearer&#39;s body during use. 
     The diaper  20  may also preferably include a pair of fasteners  50 , such as tape tabs or mechanical fasteners, positioned in the rear waist region  24  and adapted to fasten to landing areas (not shown) positioned on the garment facing surface of the front waist region  22  for fastening the diaper  20  to the wearer. Alternatively, the positions of the fasteners  50  and landing regions may be reversed. The diaper  20  may also include a variety of other features that are not depicted such as, e.g., a waist elastic feature, gasket cuffs, and barrier leg cuffs. 
     The absorbent articles of the present invention preferably include at least one seal  60  that may preferably be positioned, e.g., along the rear waist region  24 . The seal  60  may preferably be positioned such that it is centered over the small of the back of the wearer when the absorbent article (e.g., diaper  20 ) is worn such that the escape of low viscosity fecal matter (and/or liquids such as, e.g., urine) between the body facing surface of the diaper  20  and the skin may be reduced. It should be understood that the location of seal  60  on the diaper  20  is only one example of a potentially suitable location for the seal. In some instances, the seal may be located lower or be wide enough such that it overlaps a portion of the absorbent core  40  (i.e., extends over or under edge  45 B of absorbent core  40 ). 
     It may be preferred that the seal  60  be positioned to contact the portion of the small of the back that is occupied by the spine (sometimes referred to as the lumbar region). That region typically includes a depression aligned with the spine from which low viscosity fecal matter (and other materials) may be more likely to escape. Seals manufactured in accordance with the present invention may also be used in other areas of absorbent article where depressions in the anatomy may make their use advantageous. 
     It may be preferred that the seal  60  be resiliently compressible in response to compressive forces applied to the seal  60  in the z-direction (between the topsheet  30  and the backsheet  32 ). A resiliently compressible seal  60  may better conform to the anatomical contours of the subject wearing the diaper  20 . By “resiliently compressible” as used herein, it may be preferred that the seal  60  can be compressed under a compressive force applied between the topsheet  30  and the backsheet  32  (in, e.g., the z-direction) by a compressed distance from its unrestrained thickness to a reduced thickness and that, upon release of the compressive force, expands to regain at least 50% of the compressed distance, more preferably to regain at least 75% of the compressed distance, within one (1) minute after removal of the compressive force. 
     One exemplary construction of a seal  60  is depicted in the cross-sectional view of  FIG. 2  (taken along line  2 - 2  in  FIG. 1 ). The seal  60  may preferably be constructed of a continuous length of material  72  that is preferably folded to form a folded stack  70 . The folded stack  70  may preferably include layers of the material  72  folded such that each layer of the material  72  forms a segment  74  that that extends in the lateral direction  12  between folds  76  at opposing ends of each segment  74 . The folds  76  may preferably be formed along fold lines in the material  72  that are generally aligned with the longitudinal direction  10 . The material  72  of the folded stack  70  may, in some embodiments, extend across 50% or more of the rear waist region  24  (in the lateral direction  12 ) or the material  70  may be located only in a lesser portion of the lateral width of the rear waist region  24 . 
     The folds  76  may preferably be formed in the material  72  without modification. In other instances, however, the folds  76  may be formed along fold lines that may include, e.g., perforations, score lines, or other modifications to make the folding easier and/or more consistent. For example, providing a row of perforations separated by land areas along each fold  76  may result in a more uniform seal shape. 
     It may be preferred that the folded stack  70  be located between the topsheet  30  and the backsheet  32 , with the folded stack  70  located on the body facing side of the backsheet  32 . Alternatively, the folded stack  70  may be located elsewhere within the thickness of the article, e.g., the folded stack  70  may be located on the body-facing surface of the topsheet  30  (with or without an additional covering over the stack  70 ). The backsheet  32  and/or the topsheet  30  may be attached to the folded stack  70  by any suitable technique or techniques, e.g., adhesives, ultrasonic welding, thermal welding, chemical welding, etc. It may be preferred that only one of the topsheet  30  or backsheet  32  be attached to the folded stack  70  or it may be preferred that both the topsheet  30  and the backsheet  32  be attached to the folded stack  70 . 
     The folded stack  70  may preferably include segments  74  of material  72  with different (preferably progressively smaller) lengths such that the folds  76  within each segment  74  are closer together when moving from the back sheet  32  towards the topsheet  30 . Such a convex profile (referring to the shape of the folded stack  70  as depicted in the cross-sectional view of  FIG. 2 ) may better conform to the spinal depression in the lumbar region of a subject wearing the diaper  20 . It should, however, be understood that the segments  74  in the folded stack  70  of material  72  may all have the same length between folds  76  if so desired. 
     It may be preferred that the folded stack  70  include three or more layers or segments  74  of the material  72 . In some embodiments, the folded stack  70  may include five (or more) layers or segments  74  as depicted in  FIG. 2 . At an upper end, it may be preferred that the folded stack  70  include 30 or fewer layers or segments, or even 20 or fewer layers or segments. 
     The material  72  used to form the folded stack  70  may also be bonded to assist in retention of the folds during use. A number of bonds  78  between segments  74  are depicted in  FIG. 2 , although it should be understood that the depicted locations of bonds  78  are exemplary only and any suitable distribution of bonds may be used in place of the distribution depicted in  FIG. 2 . Furthermore, although the bonds in  FIG. 2  are limited to discrete locations within the stack  70 , it should be understood that the folded stack  70  may include adhesive or other bonds that occupy larger areas of the folded stack  70 . Any suitable technique or techniques may be used to provide bonds in the folded stack  70  including, but are not limited to, adhesives, ultrasonic welding, thermal welding, chemical welding, etc. 
     If the seal  60  is to be resiliently compressible, it may be preferred that the material  72  used to construct the seal  60  be resiliently compressible as well. Examples of some potentially suitable materials that may be used to create a folded stack for use as a seal may include, but are not limited to, foam material, nonwovens (such as, e.g., lofted nonwoven materials used in, e.g., batting), etc. 
     In some instances, the material  72  of the folded stack  70  may also be elastic, i.e., the material  72  may exhibit elasticity when stretched along its length and/or over its width. As used herein, the term “elasticity” (and variations thereof) means that the article in question (e.g., the material  72 ) will substantially resume a significant portion of its original shape after being stretched. It may be preferred that the recovery of an elastic portion be at least 20% of the elongation experienced as a result of moderate stretching (e.g., undergoing elongation of about 150% of original length). 
     If the material  72  of the folded stack  70  is elastic and the rear waist region  24  of the diaper  20  is also elastic, it may be preferred to include a stabilizing layer within the portion of the rear waist region  24  occupied by the folded stack  70  to limit deformation of the folded stack  70  if the rear waist region  24  is elastically stretched during use (examples of potentially suitable stabilizing layers are described in connection with other exemplary embodiments of seals herein). Such a stabilizing layer may be inelastic or elastic as desired. 
     An alternative embodiment of a seal  160  that may be used in connection with the present invention is depicted in  FIGS. 3 &amp; 4 . The seal  160  may be in the form of a stack  170  of two or more discrete segments  174  of material arranged and attached to each other to form a resiliently compressible seal  160  that may be located between the topsheet and backsheet of a diaper (not shown). Discrete segments  174  are segments of the resilient material that are not connected to each other along their ends. For example, the discrete segments  174  may be supplied by separate rolls, slit from a single roll, or provided from a stack, etc. 
     The segments  174  may preferably be bonded to each other as discussed above in connection with the folded stack to maintain a selected arrangement between the different segments. Further, it may be preferred that the segments  174  within the stack  170  have different lengths along the lateral direction  112  and those segments  174  may preferably be arranged to provide a seal  160  with a generally convex profile (as seen in  FIG. 3 ) that may better conform to the depression formed proximate the spine within the lumbar region of a wearer. 
     The materials used to form the stack  170  may preferably be similar to those used in connection with the folded stack discussed herein. In one variation, however, in a stack  170  formed from discrete segments  174 , the materials used in the segments  174  may be the same or different. For example, the materials used in different segments may have different properties such as, e.g., compressibility, firmness, elasticity, etc. It may be preferred for example, to use softer, more easily compressed materials proximate the topsheet (the body facing side of the stack  170 ) and firmer materials towards the backsheet side of the stack  170 . Such an arrangement may provide improved conformability to the seal  160 . 
     Another exemplary embodiment of a seal  260  that may be used in connection with the present invention is depicted in the cross-sectional view of  FIG. 5 . The seal  260  includes pleats  270  formed of upright segments  274  of a web material  272  using folds  276  &amp;  277  to define the upright segments  274 . Each pleat  270  preferably includes two upright segments  274  with peak fold  276  connecting the two segments  274 . The opposite ends of the upright segments  274  (the ends nearest backsheet  232 ) include base folds  277 . 
     The material  272  used to form the pleats  270  may preferably be similar to that used in connection with the folded stack discussed herein. Further, the pleats  270  (and connecting segments  275 , if provided) may be formed from a continuous length of the material used to form the pleats  270 . That material may extend, in some embodiments, across 50% or more of the width of the rear waist region in the lateral direction  212  or it may be located within only the portion of the lateral width of the rear waist region in which the seal  260  is located. 
     The upright segments  274  may preferably be oriented generally transverse to a plane that is defined by the longitudinal direction (not shown in  FIG. 5 ) and the lateral direction  212 . Such a plane may be considered as coinciding with the backsheet  232  in the embodiment of  FIG. 5 . As a result, the upright segments  274  and the pleats  270  they form may preferably extend from the backsheet  232  towards the body of a subject wearing the disposable article in which seal  260  is provided (although the opposite orientation may also be used—with the pleats  270  extending from the topsheet  230  away from the body of a subject wearing the disposable article). 
     In the depicted embodiment, adjacent pleats  270  may preferably be separated from each other in the lateral direction  212  (e.g., across the rear waist region of a diaper) as depicted in  FIG. 5 , such that adjacent pleats  270  preferably do not contact each other (when the seal  260  is uncompressed). The adjacent pleats  270  are separated from each other between base folds  277  by a lateral segment  275  that extends in the lateral direction  212 . Alternatively, the pleats in a seal according to the present invention could be located immediately adjacent each other (in the lateral direction  212 ). In such a case, it may be preferred that the base fold located between the adjacent pleats be shared, i.e., the base fold may define adjacent segments in the adjacent pleats with no lateral segment  275  being provided between the adjacent pleats. 
     The segments  274  in each of the pleats  270  may preferably include one or more bonds  278  that connect the segments  274  within the pleat  270 . The bonds  278  may assist in retaining the shape of the pleats  270  (and, therefore, the seal  260 ) in response to compression between the topsheet  230  and the backsheet  232 . Any suitable technique or techniques may be used to provide bonds  278  between the segments  274  in the pleats  270  including, but not limited to, adhesives, ultrasonic welding, thermal welding, chemical welding, etc. Although only one bond  278  is depicted in connection with each pleat  270 , it should be understood that two or more bonds may be provided or that some pleats may include one or more bonds while others do not include bonds. Further, the bonds  278  may be provided in limited areas (e.g., at points or along lines) as depicted in  FIG. 5  or, alternatively, the segments  274  within a pleat  270  may be bonded together over more significant portions of their common surfaces (i.e., the surfaces of segments  274  that face each other within the pleat  270 ). 
     Although not depicted, the pleats  270  may also be bonded or attached to the topsheet  230  and/or the backsheet  232 . Such bonds may also assist in retaining the overall shape of the pleats  270  and, therefore, the seal  260 . 
     The seal  260  may preferably include pleats  270  that include segments  274  with different lengths such that the peak folds  276  are located at different distances from the base folds  277 . It may be preferred that the pleat height (the distance between peak fold  276  and the base folds within a pleat  270 ) reach a maximum proximate a lateral center of the seal  260  as depicted in  FIG. 5  with the pleats  270  on each side of the lateral center having a decreasing pleat height. Such an arrangement may preferably provide a seal  260  having a generally convex profile (referring to the general shape of the seal  260  as depicted in  FIG. 5 ). A seal  260  with a convex profile may better conform to the spinal depression in the lumbar region of a subject wearing the article including the seal  260 . It should, however, be understood that the pleats  270  in a seal  260  may all have the same pleat height or may have any other selected arrangement (e.g., concave, sinusoidal, etc.) if so desired. 
     Still another exemplary embodiment of a seal  360  is depicted in the cross-sectional view of  FIG. 6 . In many respects, the seal  360 , which includes pleats  370  arranged in a manner similar to those found in seal  260  of  FIG. 5 , may be constructed in a manner similar to seal  260 . 
     One optional difference in pleated seal  360  as compared to pleated seal  260  is that the material used to construct the pleats  370  may be elastic such that the connecting lateral segments  375  between pleats  370  may also exhibit elasticity. In instances where it may be desirable that the material of the pleats  370  exhibit elasticity, but that the segments  375  connecting the bases of the pleats  370  do not exhibit elasticity, a stabilizing layer  379  may be provided proximate the bases of the pleats  370  to inhibit stretching of the seal  360  in the lateral direction  312  during use of the seal  360 . 
     In some instances, the stabilizing layer  379  may be inelastic, such that the portion of the waist region connected to the stabilizing layer  379  is inelastic. In other instances, the stabilizing layer  379  may itself be elastic, with the stabilizing layer  379  merely adding resistance to stretch within the portion of the waist region connected to the stabilizing layer  379 . The stabilizing layer  379  may be constructed of any suitable material or materials, e.g., nonwoven webs, filaments, multicomponent webs, films, etc. In some instances, the stabilizing layer  379  may be constructed of the same material used to form pleats  370  and/or interconnecting segments  375 . 
     The stabilizing layer  379  may be bonded to any selected component(s) within the seal  360  or the absorbent article incorporating the seal  360 , e.g., the pleats  370 , connecting segments  375 , topsheet  330 , backsheet  332 , etc. Any suitable technique or techniques may be used to provide the bonds, including, but not limited to, adhesives, ultrasonic welding, thermal welding, chemical welding, etc. 
     Where the material  372  used to form pleats  370  is elastic, the elasticity of the material  372  may be advantageously used to provide elasticity to the surrounding portions of the waist region. As seen in  FIG. 6 , the seal  360  is surrounded on each side by elastic waist portions  380 . It may be preferred that portions of the article including seal  360  include components that may be gathered on the elastic material  372  as depicted in  FIG. 6 . Such gathering may be accomplished by. e.g., attaching the topsheet  330  and the backsheet  332  to the elastic material  372  while the material  372  is stretched. When the material  372  is released, it draws or gathers the attached components in manners that are well known to those skilled in the art. 
     While a variety of embodiments of seals according to the present invention have been described herein, other potential advantages of the present invention may be found in methods of manufacturing absorbent articles incorporating the resiliently compressible seals. Such manufacturing processes are typically web-based, that is they rely on the use of webs of different materials unwound from rolls that are processed by folding, sheeting, cutting, slitting, etc. to form a desired absorbent article. In place of roll-fed assembly processes, one or more of the webs may be manufactured in line with the assembly process to potentially provide additional manufacturing advantages. 
     i. As discussed herein, a potential advantage of the seals of the present invention is their use of relatively thin webs of material that is folded into a stack, provided in discrete segments that are stacked, or formed into pleats to provide a seal with a desired thickness and resilient compressibility that cannot be provided by a single layer of the relatively thin material alone. 
       FIG. 7  depicts a system and method in which seal material  490 , which may preferably be provided in roll form or manufactured in-line with the seal assembly process, is directed into seal forming equipment  492 . The seal forming equipment  492  is preferably capable of accepting the seal material  490  in the form of a continuous web, as individual sheets (which may be fed from a continuous roll or stack), etc. Depending on the construction of the seal to be used, the seal forming equipment may convert (e.g., fold, sheet, cut, stack, pleat, etc.) the seal material  490  as needed to construct a seal which is applied to an absorbent article by an applicator  494 . In some instances, the converting and application may be completed at the same station. 
     The equipment used to convert the material in the seals of the present invention may be selected based on the properties of the materials, speed of the manufacturing process, etc. Examples of some potentially suitable converting equipment may be found in, e.g., U.S. Pat. Nos. 4,421,501 (Scheffer); 4,488,927 (Hooper); 4,614,512 (Capdeboscq); 4,682,977 (Buxton); 5,007,890 (Alverth et al.); 5,300,007 (Kober); 5,556,360 (Kober et al.), etc. If included in the seals, the seal forming equipment may include bonding apparatus (e.g., adhesive applicators, welding equipment, etc.), perforating apparatus, etc. as required to form the seals. 
       FIG. 8  depicts a portion of one continuous web  540  of resilient material that is folded for use as a waist seal. It may be preferred that the folding be along fold lines  576  that extend along the length  510  of the continuous web  540 . After folding, it may be preferred that the web  540  be separated (e.g., sheeted) along lines  544  that extend across the width of the web  540  (where the width is generally transverse to the length  510 ). 
     Also depicted in  FIG. 8  are bonds  578  between the segments  574  of the folded stack. It may be preferred that the bonds  578  (which may be formed by, e.g., applying adhesive, welding, etc.) attach the segments  574  at selected locations along the length  510  of the continuous web  540 . 
       FIG. 9  depicts a portion of another continuous web  640  of resilient material that is pleated to include pleats  670  in a pleated seal according to the present invention. It may be preferred that the pleating be along fold lines  676  that extend along the length  610  of the continuous web  640 . After the pleats  670  have been formed, it may be preferred that the pleated web  640  be separated (e.g., sheeted) along lines  644  that extend across the width of the web  640  (where the width is generally transverse to the length  610 ). 
     Also depicted in  FIG. 9  are bonds  678  between the segments  674  of the pleats  670 . It may be preferred that the bonds  678  (which may be formed by, e.g., applying adhesive, welding, etc.) attach the segments  674  at selected locations along the length  610  of the continuous web  640 . 
       FIG. 10  depicts a portion of another continuous web  740  of resilient material that includes a plurality of layers  774  stacked to form a seal including a stack of discrete segments according to the present invention. It may be preferred that the stacking be accomplished by aligning separate continuous webs for each layer  774  using, e.g., separate rolls of resilient material that are unrolled and aligned as desired. Alternatively, two or more layers  774  of the stack may be provided by slitting a single wider web into narrower webs that can be realigned to form a stacked arrangement as depicted in  FIG. 10 . At least two of the different webs and their resulting layers  774  may preferably have different widths (where width is measured generally transverse to length). In some embodiments, all of the layers  774  within the continuous web  740  may be constructed of the same material. In other embodiments, at least two layers  774  within the continuous web  740  may be constructed of different materials. 
     Each layer  774  preferably extends along the length  710  of the stacked continuous web  740 . After the stacked continuous web  740  has been formed, it may be preferred that the web  740  be separated (e.g., sheeted) along lines  744  that extend across the width of the stacked web  740  (where the width is generally transverse to the length  710 ). 
     Also depicted in  FIG. 10  are bonds  778  between the layers  774  of the stacked web  740 . It may be preferred that the bonds  778  (which may be formed by, e.g., applying adhesive, welding, etc.) attach the segments  774  at selected locations along the length  710  of the stacked web  740 . 
     Although the resiliently compressible seals have been described herein as preferably having a generally convex profile taken in a z-direction plane that is transverse to a plane formed by the lateral and longitudinal directions and parallel to the lateral direction (see, e.g., the cross-sectional or side views of  FIGS. 2 ,  3 ,  5 , and  6 ), seals having alternative profiles are also possible. For example, the seals manufactured according to the present invention may have a generally rectangular cross-section profile in such a z-direction plane. 
     In yet another alternative, although the seals depicted in the figures may have a rectangular shape in the plane defined by the lateral and longitudinal directions (e.g., the plane occupied by the paper on which  FIG. 1  is printed), seals of the present invention may have other shapes. One such alternative shape is depicted in  FIG. 11 , in which the seal  860  has a lower edge  861 , upper edge  863  and sides  865 . Both the longitudinal direction  810  and lateral direction  812  are also depicted in  FIG. 11  (with the longitudinal direction  810  and the lateral direction  812  defining the plane in which the shape of the seal  860  is defined). 
     It may be preferred that the lower edge  861  be shaped to divert the flow direction of low viscosity materials traveling in the longitudinal direction. The lower edge may preferably divert that flow at least partially along the lateral direction  812 . Flow diversion may be accomplished using any seal with a lower edge that is not aligned with the lateral direction  812  that extends across the waist region of the absorbent article (as would the lower edge of a rectangular seal aligned arranged as depicted in, e.g.,  FIG. 1 ). 
     In some embodiments, it may be preferred that the seal have a lower edge  861  that is not aligned with the lateral direction  812  and that exhibits symmetry about a centerline aligned with the longitudinal direction  810 . One such embodiment is depicted in  FIG. 11  where the seal  860  includes an intermediate section  866  flanked on both sides by outer sections  867 . It may be preferred that the intermediate section of the lower edge of seal  860  be located closer to the central region of an absorbent article (not shown in  FIG. 11 ) in which the seal  860  is used. Although one such shape for the lower edge  861  is a convex curve as depicted in  FIG. 11 , many other shapes are possible, e.g., V-shapes, etc. Low viscosity materials flowing towards the lower edge  861  along the longitudinal direction  810  may preferably be diverted to flow along the edge  861  towards the outer sections  867 . 
     Also seen in  FIG. 11  is that the upper edge  863  of the seal  860  may preferably have a shape that is complementary to the shape of the lower edge  861 . In the depicted seal, lower edge  861  is convex while upper edge  863  is concave. One potential advantage of such an arrangement is that as seals  860  are, e.g., sheeted from web that extends in the longitudinal direction  810 , little or no material is wasted because the upper edge  863  defines the lower edge of the next seal in the web. It should be noted that the longitudinal symmetry of the seal  860  also contributes to the reduced waste and complementary lower and upper edges  861  and  863 . 
     The seals used in connection with the present invention may also be characterized on the basis of the dimensions of the seals and/or the materials used to form the seals. For example, it may be preferred that the resilient material used in the stacks, pleats, etc. have a thickness of 1 millimeter (mm) or more, preferably 1.5 mm or more. It may be preferred that the upper end of the thickness of the resilient material be 4 mm or less, or even 2.5 mm or less. 
     The maximum thickness of the seals (in the z-direction) may preferably be 4 mm or more, or even 6 mm or more. At the upper end, it may be preferred that the thickness of the seal be 15 mm or less, or even 10 mm or less. 
     For folded or stacked seals as discussed herein, it may be preferred that the width of the seal at the base along the lateral direction (i.e., across the rear waist region) be 25 mm or more, or even 30 mm or more. At the upper end of the range, it may be preferred that base of the seal have a lateral direction width of 60 mm or less, or even 45 mm or less. At the top of a folded or stacked seal. it may be preferred that the top-most layer have a lateral direction width of 5 mm or more, or even 10 mm or more. At the upper end of that range, it may be preferred that the top-most layer have a lateral direction width of 35 mm or less, or even 25 mm or less. 
     In the longitudinal direction along, it may be preferred that the length of the seal be 15 mm or more, or even 20 mm or more. At the upper end of the range, it may be preferred that the longitudinal length of the seals be 50 mm or less, or even 40 mm or less. 
     The entire lateral direction width of the resilient material incorporated into the absorbent article (i.e., that portion extending laterally from the stacked/pleated portion) may, in some embodiments, preferably be 75 mm or more. At the upper end of that range, it may be preferred that the entire lateral direction width of the resilient material incorporated into the absorbent article (i.e., that portion extending laterally from the stacked/pleated portion) be 150 mm or less. 
     The complete disclosure of the patents, patent documents, and publications cited herein are incorporated by reference in their entirety as if each were individually incorporated. 
     Exemplary embodiments of this invention are discussed and reference has been made to possible variations within the scope of this invention. These and other variations and modifications in the invention will be apparent to those skilled in the art without departing from the scope of the invention, and it should be understood that this invention is not limited to the exemplary embodiments set forth herein. Accordingly, the invention is to be limited only by the claims provided below and equivalents thereof.