Patent Publication Number: US-7718021-B2

Title: Method for making a stabilized absorbent composite

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to stabilized absorbent composites and methods for making stabilized absorbent composites. The absorbent composites of the present invention are suitable for incorporation into a variety of disposable absorbent articles such as, for example, diapers, children&#39;s training pants, adult incontinence pads and garments, menstrual pads, bed pads, surgical drapes, and the like. 
     Conventional absorbent composites have traditionally been made of cellulosic fluff or other fibrous materials. Many have also included superabsorbent particles dispersed within the fibrous materials. However, many of these traditional absorbent composites have suffered from structural breakdowns during use, including, for example, cracking, separating, wadding, and/or “roping.” These problems are generally undesirable and may cause discomfort for the wearer and/or may limit the performance of the absorbent composite. 
     Additionally, some conventional absorbent composites have exhibited undesirable “gel-on-skin” wherein some of the superabsorbent particles escape the absorbent composite and stick to the wearer during use. This problem may be worse with absorbent articles having a higher amount of superabsorbent material as a percentage of the total absorbent material weight. 
     Various attempts to prevent or minimize structural breakdowns and superabsorbent losses have included, for example, densifying the cellulosic fluff, adding adhesives or other binding agents to the absorbent material, wrapping the absorbent material in nonwovens or tissues, point bonding the absorbent core, aperturing the absorbent core, needling the absorbent core, placing the superabsorbent material in pockets or discrete layers, among others. However, there still exists a need for a simple and efficient way to stabilize absorbent composites to minimize or eliminate structural breakdowns and superabsorbent losses. 
     SUMMARY OF THE INVENTION 
     In response to the discussed need, the present invention provides a method for forming and stabilizing an absorbent composite web. The method includes conforming a first web onto a forming surface. The first forming surface has a plurality of raised nubs having upper surfaces. The first web defines a plurality of bond areas corresponding to those portions of the first web overlying the upper surfaces of the nubs. The method further includes depositing absorbent material onto the first web to form a unitary absorbent core having a plurality of holes therein. The method further includes joining a second web to the first web at the bond areas to form an absorbent composite web, wherein the unitary absorbent core is positioned between the first web and the second web. The first web and the second web are bonded together through the holes in the absorbent core. Finally, the method includes removing the absorbent composite web from the forming surface. 
     In various embodiments, the method may further include applying adhesive to the second web before joining the second web to the first web and/or may include pressing the second web against the first web while the first web is conformed to the forming surface to effectuate the joining of the second web to the first web. 
     In various embodiments, the method may further include joining the first web and the second web using ultrasonic bonding, thermal bonding, or pressure bonding. 
     In various embodiments, the first web may be drawn to the forming surface via vacuum forces and the forming surface may be a drum former. 
     In various embodiments, the nubs may have a height of 1.5 to 6 mm and a surface area of 1 to 25 mm 2 . 
     In various embodiments, the absorbent material may include superabsorbent particles and cellulose fluff fibers. For example, the unitary absorbent core may include 30 to 90 percent superabsorbent particles and 70 to 10 percent cellulose fluff fibers by weight. 
     In various embodiments, portions of the absorbent composite web that include the unitary absorbent core may have a thickness of less than 6 mm. 
     In various embodiments, the method may further include scarfing the absorbent core to expose the bond areas before joining the second web to the first web. 
     In various embodiments, the first web and the second web may be tissue webs and may be joined with adhesive. In various embodiments, the first web and the second web may be nonwoven webs and may be joined by adhesive bonding, ultrasonic bonding, thermal bonding, or pressure bonding. 
     In another embodiment, the present invention provides a method for forming an absorbent composite web that includes conforming a first tissue web onto a forming surface via vacuum forces. The forming surface has a plurality of raised nubs having upper surfaces and wherein the first tissue web defines a plurality of bonding areas corresponding to those portions of the first tissue web overlying the upper surfaces of the nubs. The method further includes depositing superabsorbent and cellulose fluff onto the first tissue web to form a unitary absorbent core having a plurality of holes therein. The method further includes applying adhesive to a second tissue web, pressing the second tissue web against the first tissue web to join the first and second tissue webs at the bonding areas to form an absorbent composite web. The unitary absorbent core is positioned between the first tissue web and the second tissue web. The first tissue web and the second tissue web are bonded together through the holes in the unitary absorbent core. The method further includes removing the absorbent composite web from the forming surface. 
     In various embodiments, the method further includes scarfing the unitary absorbent core to remove substantially all absorbent material from the bond areas. 
     In various embodiments, the absorbent material may include superabsorbent particles and cellulose fluff fibers. For example, the unitary absorbent core may include 30 to 90 percent superabsorbent particles and 70 to 10 percent cellulose fluff fibers by weight. 
     In various embodiments, portions of the absorbent composite web that include the unitary absorbent core may have a thickness of less than 6 mm. 
     In another embodiment, the present invention provides a method for forming an absorbent composite web that includes conforming a first nonwoven web onto a forming surface via vacuum forces. The forming surface has a plurality of raised nubs having upper surfaces and the first nonwoven web defines a plurality of bond areas corresponding to those areas of the first nonwoven web overlying the upper surfaces of the nubs. The method further includes depositing superabsorbent and cellulose fluff onto the first nonwoven web to form a unitary absorbent core, scarfing the absorbent core to remove substantially all absorbent material from the bond areas thereby further defining a plurality of holes in the unitary absorbent core, joining the second nonwoven web to the first nonwoven web at the bond areas using adhesive bonding, ultrasonic bonding, thermal bonding, or pressure bonding to form an absorbent composite web. The unitary absorbent core is positioned between the first nonwoven web and the second nonwoven web. The first nonwoven web and the second nonwoven web are bonded together through the holes in the unitary absorbent core. The method further includes removing the absorbent composite web from the forming surface. 
     In various embodiments, the absorbent material may include superabsorbent particles and cellulose fluff fibers. For example, the unitary absorbent core may include 30 to 90 percent superabsorbent particles and 70 to 10 percent cellulose fluff fibers by weight. 
     In various embodiments, portions of the absorbent composite web that include the unitary absorbent core may have a thickness of less than 6 mm. 
     In various embodiments, the method further includes separating the absorbent composite web into discrete absorbent composites and placing the discrete absorbent composites between a bodyside liner and an outercover to form an absorbent article. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  representatively illustrates an exemplary method and apparatus of the present invention. 
         FIG. 2  representatively illustrates a perspective view of a portion of an exemplary method and apparatus of the present invention. 
         FIG. 3  representatively illustrates a portion of  FIG. 2  designated by bracket  3 . 
         FIG. 4  representatively illustrates a portion of  FIG. 2  designated by bracket  4 . 
         FIG. 5  representatively illustrates a portion of the method and apparatus of the present invention. 
         FIG. 6  representatively illustrates a cross-sectional view of the method and apparatus of  FIG. 5  taken along the line  6 - 6 . 
         FIG. 7  representatively illustrates an exemplary absorbent article of the present invention. 
         FIG. 8  representatively illustrates the absorbent article of  FIG. 7  in the laid flat condition with the side contacting the wearer facing the viewer. 
         FIG. 9  representatively illustrates an exemplary absorbent composite of the present invention. 
         FIG. 10  representatively illustrates the portion of the absorbent composite of  FIG. 9  delineated by box  10 . 
         FIG. 11  representatively illustrates a cross sectional view of  FIG. 10  taken along the line  11 - 11 . 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
       FIG. 1  representatively illustrates an exemplary method and apparatus of the present invention useful for forming absorbent composite webs. The absorbent composite webs of the present invention may be utilized in various absorbent articles, such as, for example, disposable diapers, adult incontinence articles, children&#39;s training pants, feminine hygiene articles, bandages, and the like. 
     One embodiment of the method of the present invention is illustrated generally at  20  and includes conforming a first web  22  onto a forming surface  24  having a plurality of nubs  34  ( FIG. 2 ) protruding therefrom, depositing absorbent material  26  onto the first web  22  to form a unitary absorbent core web  28 , and joining a second web  30  in facing relation with the first web  22  to form an absorbent composite web  32  wherein the absorbent core web  28  is located between the first web  22  and the second web  30 . 
     The method  20  and apparatus of the invention can include a forming chamber  44  through which the forming surface  24  is movable. The forming chamber  44  has an appointed entrance portion  46 , and an appointed exit portion  48 . A fiber source, such as provided by a fiberizer  50 , can be configured to provide fibrous material into the forming chamber  44 , and a vacuum generator or other vacuum source can be configured to provide an operative, relatively lower pressure, vacuum condition in a vacuum-commutator duct system  52 . In the illustrated configuration, the fiberizer  50  can be provided by a rotary hammer mill or a rotatable picker roll. Other fiberizers may also be employed, as desired. 
     As the forming surface  24  enters and then traverses through the forming chamber  44 , the component materials of the absorbent core web  28 , such as, the fibrous material, are operatively carried or transported by an entraining air stream that is drawn through the first web  22  and the forming surface  24 . Typically, the low pressure, vacuum generating system is constructed and arranged to produce the desired airflow through the first web  22  and the forming surface  24 . Such vacuum forming systems are well known in the art. 
     Other component materials for producing the absorbent core web  28  may also be delivered into the forming chamber  44 . For example, particles or fibers of superabsorbent material may be introduced into the forming chamber  44  by employing conventional mechanisms, such as pipes, channels, spreaders, nozzles, and the like, as well as combinations thereof. In the representatively shown configuration, the superabsorbent material can be delivered into the forming chamber  44  by employing an operative conduit and nozzle system  54 . The illustrated orientation of the delivery conduit  54  is exemplary, and it should be readily appreciated that any operative orientation of the delivery conduit and nozzle system  54  may be employed. The fibers, particles and other desired absorbent core materials may be entrained in any suitable gaseous medium. 
     The stream of air-entrained absorbent materials  26  can pass through the forming chamber  44  for deposition onto the first web  22  which overlies the forming surface  24 . The forming chamber  44  can serve to direct and concentrate the air-entrained absorbent materials  26 , and to provide a desired velocity profile in the air-entrained stream of absorbent materials  26 . Typically, the forming chamber  44  is supported by suitable structural members, which together form a support frame for the forming chamber. The frame may be anchored and/or joined to other suitable structural components, as necessary or desirable. 
     The forming surface  24  can be provided by any suitable mechanism. In the representatively shown configuration, the forming surface  24  is provided by a forming drum  56 . Other conventional techniques for providing the forming surface  24  may also be employed. For example, the forming surface  24  may be provided by an endless forming belt. Forming belt systems for producing fibrous webs are well known in the art. Examples of such forming belt systems are available from the Paper Converting Machine Company, a business having offices located in Green Bay, Wis., U.S.A.; and from Curt G. Joa Incorporated, a business having offices located in Sheboygan Falls, Wis., U.S.A. 
     In the representatively shown configuration, a forming drum system operatively provides the moving forming surface  24 . More particularly, the moving foraminous forming surface  24  can be provided by an outer peripheral surface region of a rotatable forming drum  56 . The forming drum  56  is rotatable in a selected direction of rotation, and can be rotated by employing a drum drive shaft that is operatively joined to any suitable drive mechanism (not shown). For example, the drive mechanism can include an electric or other motor which is directly or indirectly coupled to the drive shaft. While the shown arrangement provides a forming drum that is arranged to rotate in a counter-clockwise direction, it should be readily apparent that the forming drum may alternatively be arranged to rotate in a clockwise direction. 
     A suitable forming drum and forming system are taught in U.S. Pat. No. 6,630,096 to Venturino et al. issued Oct. 7, 2003, the entirety of which is incorporated herein by reference to the extent that it is consistent (i.e., not in conflict) herewith. 
     In the illustrated embodiment, under the influence of the vacuum generating source, a conveying air stream is drawn through the first web  22  and the foraminous forming surface  24  into the interior of the forming drum  56 , and is subsequently passed out of the drum through the vacuum supply conduit  58 . As the air-entrained absorbent materials  26  impinge on the first web  22 , the air component is passed through the first web  22  and the forming surface  24  and the absorbent materials  26  are retained on the first web  22  to form a nonwoven unitary absorbent core web  28  thereon. The illustrated embodiments show a continuously formed unitary absorbent core web  28  formed on the first web  22 . However, those skilled in the art will readily appreciate that discrete absorbent cores may alternatively be formed on the first web  22  such that a space exists between the absorbent cores. Therefore, where the term “absorbent core web” or “unitary absorbent core web” is used herein, the term “discrete absorbent core” or “discrete unitary absorbent core” is equally applicable in various embodiments. Suitable methods for forming discrete absorbent cores are disclosed in U.S. patent application Ser. No. 11/215,876 to Wisneski et al. entitled “Method and Apparatus for Making Absorbent Article With Core Wrap” and filed on Aug. 30, 2005, the entirety of which is incorporated herein by reference to the extent that it is consistent (i.e., not in conflict) herewith. 
     Optionally, a scarfing system may be positioned at the exit region  48  of the forming chamber  44 . The scarfing system can include a scarfing chamber  60  and a scarfing roll  62  which is positioned within the scarfing chamber. The scarfing roll can abrade excess absorbent material  26  from the absorbent core web  28 , and the removed fibers can be transported away from the scarfing chamber  60  with a suitable discharge conduit, as is well known in the art. The removed absorbent material  26  may, for example, be recycled back into the forming chamber  44  or the fiberizer  50 , as desired. Additionally, the scarfing roll can rearrange and redistribute the web material along the longitudinal machine-direction of the web and/or along the lateral cross-direction of the web. 
     The rotatable scarfing roll may be operatively connected and joined to a suitable shaft member, and may be driven by a suitable drive system (not shown). The scarfing roll system can provide a conventional trimming mechanism for removing or redistributing any excess, z-directional thickness of the absorbent core web  28  that has been deposited on the first web  22 . The surface of the scarfing roll can be adjusted to provide a desired contour along the scarfed surface of the absorbent core web  28 . The scarfing roll can, for example, be configured to provide a substantially flat surface along the scarfed surface of the absorbent core web  28 . The scarfing roll can optionally be configured to provide a non-flat surface. The scarfing roll  62  is disposed in spaced adjacent relationship to the forming surface  24 , and the forming surface  24  is translated past the scarfing roll. A conventional transporting mechanism, such as a suction fan (not shown) can draw the removed fibrous material away from the formed absorbent core web  28  and out from the scarfing chamber  60 . 
     The scarfing roll  62  may be rotated in a direction which moves a contacting surface of the scarfing roll in a counter-direction that is opposite the movement direction of the absorbent core web  28 . Alternatively, the scarfing roll  62  may be rotated in a co-direction that is the same as the movement direction of absorbent core web  28 . In either situation, the rotational speed of the scarfing roll  62  should be suitably selected to provide an effective scarfing action against the contacted surface of the formed absorbent core web  28 . In like manner, any other suitable trimming mechanism may be employed in place of the scarfing roll assembly to provide a cutting or abrading action to the laid fibrous web by a relative movement between the fibrous web and the selected trimming mechanism. A suitable scarfing system is taught in U.S. Pat. No. 6,627,130 to Kugler et al. issued Sep. 30, 2003, the entirety of which is incorporated herein by reference to the extent that it is consistent (i.e., not in conflict) herewith. 
     After formation of the absorbent core web  28 , the second web  30  is overlaid upon the absorbent core web  28  and the first web  22  while both are conformed to the forming surface  24  and the nubs  34  ( FIG. 2 ) protruding therefrom. The second web  30  is then joined to the first web  22  while still conformed to the forming surface  24  and the nubs  34  to form the completed absorbent composite web  32 . Subsequently, with the rotation of the drum, the formed absorbent composite web  32  can be removed from the forming surface  24 . The removal operation may be provided by the weight of the absorbent composite web  32 , by centrifugal force, by a positive air pressure, or by combinations thereof. The positive air pressure can be produced, for example, by a source of compressed air or a fan which generates a pressurized air flow that exerts a force directed outwardly through the forming surface. 
     The portion of the forming surface  24  that is carrying the absorbent composite web  32  can be moved to an optional pressure blow-off zone of the forming drum system. In the blow-off zone, air can be introduced under pressure and directed radially outwardly against absorbent composite web  32  on the portion of the forming surface that becomes aligned with the blow-off zone. The gas pressure can effect a ready release of the absorbent composite web  32  from the forming surface  24 , and the absorbent composite web  32  can be removed from the forming surface onto a suitable transport mechanism. 
     A web transporter can receive the absorbent composite web  32  from the forming drum  56 , and convey the absorbent composite web  32  for further processing. In various embodiments, portions the absorbent composite web  32 , such as the first web  22  and/or the second web  30 , may be folded to seal the edges of the absorbent core web  28 . 
     Suitable web transporters can, for example, include conveyer belts, vacuum drums, transport rollers, electromagnetic suspension conveyors, fluid suspension conveyors, or the like, as well as combinations thereof. As representatively shown, the web transporter can be provided by a system which includes the illustrated endless conveyor belt  64  disposed about rollers  66 . In a particular configuration of the invention, a vacuum suction box  68  can be located below the conveyor belt  64  to help remove the absorbent composite web  32  from the forming surface  24 . The vacuum box  68  opens onto the belt  64 , and a suction of air out of the vacuum box can draw an air flow through perforations in the conveyor belt. This flow of air can, in turn, operate to draw the absorbent composite web  32  away from the forming surface. The vacuum box can be employed with or without the use of a positive pressure in the blow-off zone. 
     With reference to  FIG. 2 , the forming surface  24  can be provided along the outer, cylindrical surface of the forming drum  56 , and can extend along the axial (cross-directional) and circumferential (machine-directional) dimensions of the forming drum. The structure of the forming surface  24  can be composed of an assembly, and can include a foraminous or otherwise porous member  70  which is operatively connected and joined to the forming drum  56 . 
     The porous forming member  70  can extend along the outer, circumferential periphery of the forming drum  56 . The forming member  70  can be composed of any suitable porous material. The foraminous member  70  may include a screen, a wire mesh, a hard-wire cloth, a perforated member, or the like, as well as combinations thereof. In a particular aspect, the foraminous member can include a fluted member having open channels which can extend generally radially and can allow a substantially free flow of air or other selected gas from the outward-side of the drum towards the center of the drum. The flutes or channels can have any desired cross-sectional shape, such as circular, oval, hexagonal, pentagonal, other polygonal shape, or the like, as well as combinations thereof. Such honeycomb structures are well known in the art, and can be composed of various materials, such as plastic, metal, ceramics, and the like, as well as combinations thereof. For example, suitable materials and structures are available from Innovent, a business having offices located in Peabody, Mass., U.S.A. 
     In various embodiments, the radially outward surface of the fluted member or other foraminous member  70  can be configured with a selected surface contour. The contoured surface regions of the foraminous member  70  can be formed to have any operative shape. In various arrangements, the contour shape can be trapezoidal. Alternatively, the contour shape can be domed or flat. 
     The forming surface  24 , and particularly the porous member  70 , can include a forming surface contour which is uniform or non-uniform along its depth dimension. For example, the forming surface  24  can provide a relatively low-basis-weight region, and at least one relatively high-basis-weight region, such as provided by pocket regions. In various embodiments, at least one relatively high basis weight region can be positioned along a medial region of the forming surface  24 . Alternatively, at least one relatively high basis weight region can be positioned along one or more other, non-medial regions of the forming surface  24 . 
     With reference to  FIGS. 2 ,  3 ,  5  and  6 , at least one side-masking member, such as provided by a side contour ring  72  can be disposed on the foraminous member  70 . In various embodiments, the invention can include a cooperating system of side-masking members. As representatively shown, a pair of laterally opposed, side contour ring members  72  can be configured to extend circumferentially around the forming drum  56 . In a particular aspect, the contour rings  72  can be operatively attached and positioned along laterally opposed, outboard edge regions of the foraminous member  70 . The contour rings  72  can be joined and assembled to the forming surface  24  by employing conventional attaching or mounting mechanisms. 
       FIG. 2  representatively illustrates a perspective view of the first web  22  conforming to a forming surface  24  with portions of the absorbent material  26  and portions of the first web  22  cut away along line  84  to illustrate underlying details.  FIG. 3  representatively illustrates a more detailed view of the portion of  FIG. 2  designated by bracket  3  with the absorbent material  26  removed to illustrate underlying details.  FIG. 4  representatively illustrates a more detailed view of the portion of  FIG. 2  designated by bracket  4 . 
     Referring now to  FIGS. 2 and 3 , the forming surface  24  includes a plurality of raised nubs  34  having upper surfaces  36 . In various embodiments, the raised nubs  34  may also have side surfaces  38 . The first web  22  is conformed about the forming surface  24  and the plurality of nubs  34 . The first web  22  may be drawn down to the forming surface  24  and around the nubs  34  via vacuum forces or the like. The first web  22  overlies the forming surface  24  and the nubs  34  and defines a plurality of bonding areas  40 . The bonding areas  40  correspond to those portions of the first web  22  overlying the upper surfaces  36  of the nubs  34 . 
     As used herein, the terms “conform,” “conforming,” or derivatives thereof mean to give the same shape, outline, or contour to. For example, when the first web  22  is “conformed” to the forming surface  24 , the first web  22  is generally in contact with most of the forming surface  24  and at least the upper surfaces  36  of the nubs  34 . See  FIG. 6  for an example of the first web  22  conforming to the forming surface  24  and the nubs  34 . 
     The nubs  34  may be formed out of a wide variety of different materials. For example, the nubs  34  may be formed out of plastic, metal, ceramin, or the like, or combinations thereof. Metallic nubs are advantageous because they are durable and have a relatively low coefficient of friction. An aluminum nub provided with polytetrafluorethylene or other suitable release coating can be used to provide a durable and low friction nub. 
     The nubs  34  may be attached to the forming surface  24  by using any suitable means such as, for example, fasteners, welding, adhesives, and the like, and combinations thereof. Alternatively, the nubs  34  may be formed integrally with the forming surface  24 . In various embodiments, the nubs  34  may be the heads of various fasteners, such as, for example, bolts or screws, or the like, having any suitable head, such as, hex heads, button heads, socket heads, cap heads, or the like, or combinations thereof. For example, in some embodiments, the nubs  34  may be bolts secured to the forming surface  24 . The nubs  34  are illustrated as lying within the interior region of the forming surface whereby the nubs  34  will be completely circumscribed by the absorbent material  26  deposited on the first web  22  overlying the forming surface  24 . However, in various embodiments, the nubs  34  may be located at the edges of the forming surface whereby only a portion of one or more nubs  34  may be circumscribed by the absorbent material  26 . 
     The illustrated nubs  34  do not include perforations or apertures on either the side surfaces  38  or upper surfaces  36  of the nub  34  and, thus, process air is not pulled directly through the illustrated nubs  34 . It would be possible, however, for the nubs to include such openings on the side surface  38  to allow the process air to be removed there though in addition to the remainder of the forming surface  24 . 
     In various embodiments, the surface area of any individual nub  34  may be 1 mm 2  (0.0015 in 2 ) to 200 mm 2  (0.3 in 2 ), 1 mm 2  (0.0015 in 2 ) to 100 mm 2  (0.155 in 2 ), or 1 mm 2  (0.0015 in 2 ) to 25 mm 2  (0.03875 in 2 ). In some embodiments, the surface area of any individual nub  34  may be less than 200 mm 2 , less than 100 mm 2 , less than 90 mm 2 , less than 80 mm 2 , less than 70 mm 2 , less than 60 mm 2 , less than 50 mm 2 , less than 40 mm 2 , less than 30 mm 2 , less than 20 mm 2 , or less than 10 mm 2 . In various embodiments, the total nub surface area may be between about 1 to about 33 percent, about 1 to about 25 percent, or less than about 10 percent of the total forming surface area. As used herein, the total nub surface area is the combined cross sectional area of the nubs at the base of the nubs where the nubs are attached to the forming surface. The total forming surface area includes the area of the forming surface on which the absorbent material is deposited plus the total nub surface area. 
     In various embodiments, the nubs  34  may have any suitable height. The nub height represents the perpendicular distance that the upper surface  36  of the nubs  34  extends from the forming surface  24 . In various embodiments, the nubs  34  may have a height less than 10, less than 9, less than 8, less than 7, less than 6, less than 5, less than 4, less than 3, or less than 2 mm. In some embodiments, the nubs  34  may have a height of 1 mm to 10 mm, 1 mm to 7 mm, or 1.5 mm to 6 mm. 
     The nubs  34  may have a variety of different shapes and/or configurations. For example, the cross section of the nubs  34  may define a circle, oval, star, diamond, rectangle, or any other geometric figure. In some embodiments, the nubs  34  may have an irregular cross sectional shape or may be generally linear or arcuate. Furthermore, the cross sectional shape of the nubs  34  may vary over the height of the nubs  34 . For example, the nubs  34  may be provided with a slight taper whereby the upper surface  36  of the nub  34  has an area which is less than the cross sectional area of the base of the nub at the point where the nub is attached to the forming surface  24 . The inward taper of the side surfaces  38  may be in the range of between 0° to about 15°. For example, side surfaces may have an inward taper of approximately 5° or 7°. 
     Alternatively, the side surfaces  38  of the nubs  34  may be perpendicular to the forming surface  24 , pitched slightly outward, or vary over the perimeter or height of the nub  34 . For example, a, nub  34  could have a leading edge  74  which is perpendicular to the forming surface and a trailing edge  76  which is pitched slightly inward and thus have a pitch which varies over the perimeter of the nub  34 . A nub  34  which is perpendicular near its base (i.e., has a 0° taper) but tapers inwardly near its distal end would have a pitch which varies over the height of the nub  34 . Thus, the nubs  34  may take a variety of different shapes. The configuration of the nubs  34 , however, must account for the interaction of the nub  34  and the first web  22  and the absorbent core web  28 . 
     In some embodiments, the nubs  34  may have a circular shape. The nubs  34  may have a diameter of 1 mm to 16 mm, 1 mm to 10 mm, or 1 mm to 5 mm. In some embodiments the nubs  34  may have a diameter of less than 16 mm, less than 10 mm, or less than 5 mm. The pattern formed by the nubs  34  on the forming surface  24  may be varied significantly. 
     Referring now to  FIGS. 2 and 4 , the method  20  further includes-depositing absorbent material  26  onto the first web  22  to form a unitary absorbent core web  28  having a plurality of holes  41  formed therein. The absorbent material  26  surrounds the bonding areas  40  which overlie the nubs  36  thereby defining the holes  41 . The unitary absorbent core web  28  defines lateral side edges  31 . In embodiments with discrete absorbent cores, the discrete absorbent cores further define longitudinal end edges  80  (see  FIG. 9 ). In various embodiments, the bonding areas  40  of the first web  22  are free of absorbent material  26  or substantially free of absorbent material  26 . In various embodiments, the bonding areas  40  may include some absorbent material  26  that is removed prior to subsequent processing. In some embodiments, the scarfing roll  62  can optionally be configured to remove most or all deposited absorbent material  26  from the bonding areas  40  of the first web  22 . 
     As used herein, the term “unitary” means “undivided” and describes an absorbent core wherein no portion of the absorbent core is completely disconnected from any other portion. The unitary absorbent core includes a plurality of holes wherein a first sheet and a second sheet are bonded together through the plurality of holes to form an absorbent composite. In other words, a unitary absorbent core is a “sea” of absorbent material with “islands” of bond points. In contrast, some prior art absorbent cores formed discrete pockets of absorbent material encapsulated between sheets that were connected together between the pockets to create a “sea” of bond areas with “islands” of absorbent material. 
     Unitary absorbent cores can be formed discretely or can be formed as webs. As used herein, the term “unitary absorbent core web” describes a series of unitary absorbent cores directly connected together to form a web. As used herein, the term “discrete unitary absorbent core” describes a unitary absorbent core that is formed such that it is not directly connected to another unitary absorbent core. 
     The method  20  further includes joining a second web  30  to the first web  22  on upper surfaces  36  of the nubs  34  to form an absorbent composite web  32  upon the forming surface  24 .  FIG. 5  representatively illustrates a portion of the method  20  not seen in  FIG. 2  wherein the second web  30  is joined in facing relation to the first web  22  at bond points  45  to form the absorbent composite web  32 . The bond points  45  correspond to the bonding areas  40  of the first web  22 . In various embodiments, the second web  30  may additionally be joined to the first web  22  at marginal areas  42 . The marginal areas  42  are defined as the areas outboard of the absorbent core lateral side edges  78  and the longitudinal end edges  80 . 
     As used herein, the use of the term “join,” “joined,” “joining,” or variations thereof in describing the relationship between two elements means that the two elements can be connected together by heat sealing, ultrasonic bonding, adhesive bonding, thermal bonding, pressure bonding, stitching, or the like, or combinations thereof. Further, the two elements can be joined directly together (i.e., touching), or may have one or more elements interposed between them, all of which are suitably connected together. 
     In the illustrated embodiments, the absorbent core web  28  is formed as a continuous web and therefore the marginal areas  42  extend beyond the lateral side edges  78  of the absorbent core web  28 . However, those skilled in the art will readily appreciate that discrete absorbent cores may be formed such that a space exists between subsequent absorbent cores. As such, the marginal areas  42  may therefore extend around the entire perimeter  29  of the absorbent core ( FIG. 9 ). Suitable methods for forming discrete absorbent cores is disclosed in U.S. patent application Ser. No. 11/215,876 to Wisneski et al. entitled “Method and Apparatus for Making Absorbent Article With Core Wrap” and filed on Aug. 30, 2005, the entirety of which is incorporated herein by reference to the extent that it is consistent (i.e., not in conflict) herewith. 
       FIG. 6  representatively illustrates a cross sectional view of the absorbent composite web  32  on the forming surface  24  taken along the line  6 - 6  of  FIG. 5 . The first web  22  is conformed to the forming surface  24  and overlays the nubs  34  and the side contour rings  72  at the marginal area  42 . The portions of the first web  22  overlying the upper surfaces  36  of the nubs  34  define the bonding areas  40 . The absorbent material  26  is formed upon the first web  22  and surrounds the nubs  34  to form the unitary absorbent core web  28  having holes  41  therein. The holes  41  are defined by the nubs  34 . The bonding areas  40  of the first web  22  are exposed within the holes  41 . The absorbent core web  28  also includes a perimeter  29  defined in part by the side contour rings  72 . The second web  30  is overlaid on the first web  22  and the unitary absorbent core web  28 . The second web  30  is joined to the first web  22  at the bonding areas  40  to form bond points  45 . The second web  30  may also be joined to the first web  22  at the marginal areas  42 . Therefore, the absorbent composite web  32  is stabilized because the first web  22  and the second web  30  are joined together at bond points  45  which extend through holes  41  in the absorbent core web  28  located between the first web  22  and the second web  30 . 
     The second web  30  may be joined to the first web  22  by any suitable means to form the absorbent composite web  32 . In various embodiments, the second web  30  may be joined to the first web  22  at the bonding areas  40  and/or the marginal areas  42  by adhesive bonding, ultrasonic bonding, thermal bonding, pressure bonding, and the like, and combinations thereof to form the absorbent composite web  32 . The joining at the bonding areas  40  results in bond points  45 . 
     In some embodiments, the second web  30  may be joined to the first web  22  by applying adhesive to the second web  30  before overlying the second web  30  in facing relation with the first web  22  and the unitary absorbent core web  28 . The second web  30  may then be directly joined to the bonding areas  40  of the first web  22  via the adhesive to form the absorbent composite web  32  having bond points  45 . In various embodiments, the adhesive may be applied to the first web  22  and/or the second web  30  in any suitable pattern or covering any suitable surface area. For example, the adhesive pattern may include meltblown, swirl, slot coat, beads, or the like, or combinations thereof. The adhesive may be applied across at least 50 percent, at least 60 percent, at least 70 percent, at least 80 percent, or at least 90 percent of the surface area of the first web  22  and/or the second web  30 . The adhesive is preferably applied to at least those portions of the second web  30  that align with the bonding areas  40  of the first web  22  to effectuate the joining of the webs  22  and  30  at the bonding areas  40  to form the bond points  45 . 
     In various embodiments, adhesive may be applied to the first web  22 , the second web  30 , or both the first web  22  and the second web  30  before the second web  30  is overlaid upon the absorbent core web  28  and the first web  22 . In various embodiments, the second web  30  may be pressed against the bonding areas  40  to effectuate a stronger joining at the bond points  45  between the first web  22  and the second web  30  while on the forming surface  24 . 
     In various embodiments, the second web  30  may be joined to the first web  22  at the marginal areas  42  to define a flange  43 . The flange  43  may extend beyond the perimeter  29  of the unitary absorbent core web  28  by any suitable distance. The flange  43  may be subsequently cut by any suitable means into any suitable shape and suitable contour. For example, in some embodiments, the flange  43  may be cut using a die cutter, high pressure water cutter, or the like, and may be shaped to follow the lateral side edges  78  of the unitary absorbent core web  28 . In some embodiments, including the forming of discrete absorbent cores, the flange  43  may be generally shaped to follow the entire perimeter  29  of the discrete absorbent core ( FIG. 9 ). 
     In some embodiments, the marginal areas  42  of the first web  22  may be folded around the absorbent core web  28  and joined to the second web  30  to seal the lateral edges  78  of the absorbent core web  28 . In some embodiments, the marginal areas  42  of the second web  30  may be folded around the absorbent core web  28  and joined to the first web  22  to seal the lateral edges  78  of the absorbent core web  28 . In some embodiments, the flange  43  formed by the first web  22  and the second web  30  may be folded around the absorbent core web  28  and joined to first web  22  and/or the second web  30 . Any suitable means may be used to fold the first web  22 , the second web  30 , and/or the flange  43 . For example, conventional folding boards, and the like, may be used. Suitable folding methods and apparatus are disclosed in U.S. patent application Ser. No. 10/955,820 to Mischler et al., filed on Sep. 30, 2004, the entirety of which is incorporated herein by reference to the extent that it is consistent (i.e., not in conflict) herewith 
     The present invention advantageously forms holes  41  in the absorbent core web  28  around the bonding areas  40 . The first web  22  and the second web  30  are joined together through the holes  41  at the bonding areas  40  to form bond points  45  while the first web  22  is conformed about the nubs  34  and the absorbent core web  28  is formed about the nubs  34  thereby ensuring registration between the bonding areas  40  and the holes  41 . Furthermore, having both the hole formation step and the bonding step occur on the same forming surface  24  allows the size of the hole  41  to be very similar to the size of the bond point  45  in the bonding area  40  because both are created by the same nub  34  while still engaged with the nub  34 . In other words, the bond points  45  cannot get out of registration with the holes  41 . 
     In some embodiments, the first web  22  may provide the functions of both the first web  22  and the second web  30 . For example, the first web  22  may define a forming section and a wrap section. The first web  22  may be provided at a width substantially wider than the width of the absorbent core web  28 . The absorbent core web  28  may be formed on the forming section of the first web  22  as described herein and the wrap section of the first web  22  may be folded and overlaid upon the absorbent core web  28  and joined to the forming section as described herein to create the absorbent composite web  32 . 
     In various embodiments, the absorbent composite web  32  may be compressed or densified by any suitable means, such as, for example, passing the absorbent composite web  32  through a fixed gap nip commonly referred to as debulking. Debulking the absorbent composite web  32  compresses and expands the unitary absorbent core web  28  and reduces the size of the holes  41 . Therefore, the size of the holes  41  approaches the size of the bond points  45  and results in minimally oversized holes  41  as compared to the bond points  45 . 
     In various embodiments, the first web  22  may be a tissue web, the second web  30  may be a tissue web, and the second web  30  may be joined to the first web  22  at the bonding areas  40  to form bond points  45  with adhesive or any other suitable means. 
     In various embodiments, the first web  22  may be a nonwoven web, the second web  30  may be a nonwoven web, and the second web  30  may be joined to the first web  22  at the bonding areas  40  to form bond points  45  by adhesive bonding, ultrasonic bonding, pressure bonding, thermal bonding, or the like, or combinations thereof. 
     In various embodiments, the first web  22  and the second web  30  may be provided by a similar material. Alternatively the first web  22  and the second web  30  may be provided by dissimilar materials. The first web  22  may be adapted to face a user&#39;s body during use, and the second web  30  may be adapted to face away from the user&#39;s body during use or the first web  22  may be adapted to face away from a user&#39;s body during use, and the second web  30  may be adapted to face the user&#39;s body during use. 
     Various woven and nonwoven fabrics may comprise the first web  22  and/or the second web  30 . For example, the first web  22  and/or the second web  30  may be composed of a meltblown or spunbonded web of polyolefin fibers. The first web  22  and/or the second web  30  may also be a bonded-carded web composed of natural and/or synthetic fibers. The first web  22  and/or the second web  30  may be composed of a substantially hydrophobic material, and the hydrophobic material may, optionally, be treated with a surfactant, or otherwise processed, to impart a desired level of wettability and hydrophilicity. Specifically, the first web  22  and/or the second web  30  may be a nonwoven, spunbond-meltblown-spunbond, polypropylene fabric having a basis weight of about 5 to 30 gsm. 
     The first web  22  and/or the second web  30  may be stretchable, either elastically or extensibly, thereby allowing the absorbent core web  28  to swell. The first web  22  and the second web  30  may suitably be composed of a material which is either liquid permeable or liquid impermeable. It is generally desirable that at least one of the first web  22  and the second web  30  be formed from a material which is substantially liquid permeable. The liquid permeability may be inherent in the first web  22  and/or the second web  30 , such as in the example of a low basis weight spunbond. Alternatively, the permeability may result from the first web  22  and/or the second web  30  that is inherently liquid impermeable, such as in the example of a film, which has been modified to provide the permeability, for example by aperturing. 
     Other suitable materials for the first web  22  and/or the second web are described in commonly assigned U.S. patent application Ser. No. 11/020,842 to Abuto et al., entitled, “Stretchable Absorbent Core and Wrap,” filed Dec. 21, 2004, the entirety of which is incorporated herein by reference to the extent that it is consistent (i.e., not in conflict) herewith. The first web  22  and/or the second web  30  may be manufactured by any suitable means, such as, for example the processes described in U.S. Pat. No. 5,458,592 to Abuto et al. and issued Oct. 17, 1995, the entirety of which is incorporated herein by reference to the extent that it is consistent (i.e., not in conflict) herewith. 
     In some embodiments, the absorbent composite web  32  may be separated into discrete absorbent composites  90  by any suitable means, such as, for example, rotary cutters, high pressure water cutters, die cutters, saw cutters, and the like. The separation of the absorbent composite web  32  into discrete absorbent composites  90  includes the separation of the first web  22  into discrete first sheets  92  and the second web  30  into discrete second sheets  93 . As discussed herein, the absorbent core may be formed as a continuous absorbent core web  28  and cut into discrete absorbent cores  91  or may be formed as discrete absorbent cores  91 . Therefore, the separation of the absorbent composite web  32  into discrete absorbent composites  90  may or may not require the separation of the absorbent core web  28  into discrete absorbent cores  91 . 
     Referring now to  FIGS. 7 and 8 , the discrete absorbent composite  90  of the present invention is representatively illustrated as part of a baby diaper. The baby diaper is indicated in its entirety by the reference numeral  120 . The diaper  120  can suitably be disposable, which refers to articles that are intended to be discarded after a limited period of use instead of being laundered or otherwise conditioned for reuse. It should also be understood that the absorbent composite  90  of the present invention is suitable for use with various other absorbent articles intended for personal wear, including, but not limited to, children&#39;s training pants, feminine hygiene products, incontinence products, medical garments, surgical pads and bandages, other personal care or health care garments, and the like, without departing from the scope of the present invention. 
     By way of illustration only, various materials and methods for constructing diapers such as the diapers  120  of the various aspects of the present invention are disclosed in U.S. patent application Ser. No. 10/836,490, filed Apr. 29, 2004, in the name of Schlinz et al.; U.S. Pat. No. 5,496,298 issued Mar. 5, 1996, to Kuepper et al.; U.S. Pat. No. 4,798,603 issued Jan. 17, 1989, to Meyer et al.; U.S. Pat. No. 5,176,668 issued Jan. 5, 1993, to Bernardin; U.S. Pat. No. 5,192,606 issued Mar. 9, 1993, to Proxmire et al., and U.S. Pat. No. 5,509,915 issued Apr. 23, 1996, to Hanson et al., each of which are incorporated herein by reference to the extent that they are consistent (i.e., not in conflict) herewith. 
     The diaper  120  is illustrated in  FIG. 7  in a fastened condition. The diaper  120  is illustrated in  FIG. 8  in a laid flat and unfastened condition with portions cut away to illustrate underlying detail. The diaper  120  defines a longitudinal direction  146  and a lateral direction  148  perpendicular to the longitudinal direction as shown in  FIG. 8 . The diaper  120  further defines a pair of longitudinal end regions, otherwise referred to herein as a front waist region  122  and a back waist region  124 , and a center region, otherwise referred to herein as a crotch region  126 , extending longitudinally between and interconnecting the front and back waist regions  122 ,  124 . The front and back waist regions  122 ,  124  include those portions of the diaper  120 , which, when worn, wholly or partially cover or encircle the waist or mid-lower torso of the wearer. The crotch region  126  generally is that portion of the diaper  120  which, when worn, is positioned between the legs of the wearer and covers the lower torso and crotch of the wearer. The diaper  120  also defines an inner surface  128  adapted to be positioned toward the wearer, and an outer surface  130  opposite the inner surface. With additional reference to  FIG. 8 , the diaper  120  has a pair of opposed article side edges  136  extending in the longitudinal direction  146  and a pair of opposed article waist edges  138  extending in the lateral direction  148 , referred to herein as the article back waist edge and the article front waist edge. 
     The illustrated diaper  120  can include an absorbent chassis, generally indicated at  132 . The absorbent chassis  132  can define a first chassis side edge  190  extending in the longitudinal direction  146  and a second chassis side edge  191  extending in the longitudinal direction  146 , opposite the first chassis side edge  190 . The absorbent chassis  132  can also define a pair of longitudinally opposite chassis waist edges referred to herein as the chassis back waist edge  192  and the chassis front waist edge  194 . 
     For example, in the aspect of  FIGS. 7 and 8 , the diaper  120  includes an absorbent chassis  132  and a pair of ears  134  formed separately from and attached to the absorbent chassis  132  proximate the first chassis side edge  190  and the second chassis side edge  191 . The ears  134  can be attached along seams  156  proximate the chassis side edges  190 ,  191  in either the front waist region  122  or in the back waist region  124  of the diaper  120 . In the illustrated aspects, the ears  134  are attached in the back waist region  124 . The ears  134  may be attached to the absorbent chassis  132  using means known to those skilled in the art such as adhesive, thermal bonding, pressure bonding, ultrasonic bonding, and the like, or combinations thereof. In alternative embodiments, the ears  134  may be formed as an integral part of the absorbent chassis  132 . The ears  134  may also include fasteners  160 , as are known in the art, adapted to releasably secure the diaper  120  about the waist of the wearer. 
     The absorbent chassis  132  is illustrated in  FIG. 8  as being substantially I-shaped. However, it is contemplated that the absorbent chassis  132  may have other shapes (e.g., hourglass, T-shaped, rectangular, and the like) without departing from the scope of this invention. 
     The absorbent chassis  132  can include an outercover  140  and a bodyside liner  142  in a superposed relation therewith. The liner  142  can be suitably joined to the outercover  140  along at least a portion of the absorbent chassis  132 . The liner  142  can be suitably adapted, i.e., positioned relative to the other components of the diaper  120 , to contact the wearer&#39;s skin during wear of the diaper. The absorbent chassis  132  may also include the absorbent composite  90  disposed on the inner surface of the article relative to the outercover  140  for absorbing liquid body exudates. For example, the absorbent composite  90  can be located between the outercover  140  and the bodyside liner  142 . The bodyside liner  142  and the outercover  140  can be attached to each other by adhesive, ultrasonic bonding, thermal bonding or by other suitable attachment techniques known in the art. Moreover, at least a portion of the absorbent composite  90  can optionally be attached to the bodyside liner  142  and/or the outercover  140  utilizing the methods described above. The liner  142  can be coextensive with the outercover  140  or can be larger or smaller than the outercover  140 . 
     As discussed herein, the discrete absorbent composite  90  includes a first sheet  92  and a second sheet  93  joined together at a plurality of bond points  45 . The absorbent core  91  is located between the first and second sheets  92  and  93  and the bond points  45  extend through the holes  41  within the absorbent core  91 . 
     The diaper  120  can optionally include a pair of containment flaps  155  for inhibiting the lateral flow of body exudates. The containment flaps  155  can be operatively attached to the diaper  120  in any suitable manner as is well known in the art. In particular, suitable constructions and arrangements for the containment flaps are generally well known to those skilled in the art and are described in U.S. Pat. No. 4,704,116 issued Nov. 3, 1987, to Enloe, which is incorporated herein by reference to the extent that it is consistent (i.e., not in conflict) herewith. 
     To further enhance containment and/or absorption of body exudates, the diaper  120  may optionally include waist elastic members  154  in the front and/or back waist regions  122  and  124  of the diaper  120 . Likewise, the diaper  120  may optionally include leg elastic members  158 , as are known to those skilled in the art. The waist elastic members  154  and the leg elastic members  158  can be formed of any suitable elastic material that is well known to those skilled in the art. For example, suitable elastic materials include sheets, strands or ribbons of natural rubber, synthetic rubber, or thermoplastic elastomeric polymers. In one aspect of the invention, the waist elastics and/or the leg elastics may include a plurality of dry-spun coalesced multi-filament spandex elastomeric threads sold under the trade name LYCRA and available from Invista of Wilmington, Del., U.S.A. 
     The outercover  140  may suitably include a material that is substantially liquid impermeable. The outercover  140  may be provided by a single layer of liquid impermeable material, or more suitably include a multi-layered laminate structure in which at least one of the layers is liquid impermeable. In particular aspects, the outer layer may suitably provide a relatively cloth-like texture to the wearer. A suitable liquid impermeable film for use as a liquid impermeable inner layer, or a single layer liquid impermeable outercover  140  is a 0.025 millimeter (1.0 mil) polyethylene film commercially available from Edison Plastics Company of South Plainfield, N.J., U.S.A. Alternatively, the outercover  140  may include a woven or nonwoven fibrous web layer that has been totally or partially constructed or treated to impart the desired levels of liquid impermeability to selected regions that are adjacent or proximate the absorbent body. 
     The outercover  140  may also be stretchable, and in some aspects it may be elastomeric. For example, such an outercover material can include a 0.3 osy polypropylene spunbond that is necked 60 percent in the lateral direction, creped 60 percent in the longitudinal direction, and laminated with 3 grams per square meter (gsm) Bostik-Findley H2525A styrene-isoprene-styrene based adhesive to 8 gsm PEBAX 2533 film with 20 percent TiO 2  concentrate. Reference is made to U.S. Pat. No. 5,883,028, issued to Morman et al., U.S. Pat. No. 5,116,662 issued to Morman and U.S. Pat. No. 5,114,781 issued to Morman, all of which are hereby incorporated herein by reference, for additional information regarding suitable outercover materials. 
     The bodyside liner  142  is suitably compliant, soft-feeling, and non-irritating to the wearer&#39;s skin. The bodyside liner  142  is also sufficiently liquid permeable to permit liquid body exudates to readily penetrate through its thickness to the absorbent composite  90  and the absorbent core  91  located therein. A suitable liquid permeable bodyside liner  142  is a nonwoven polyethylene/polypropylene bi-component web having a basis weight of about 27 gsm; the web may be spunbonded or a bonded carded web. Optionally, the bodyside liner  142  may be treated with a surfactant to increase the wettability of the liner material. 
     Alternatively, the bodyside liner  142  may also be stretchable, and in some aspects it may be elastomeric. For instance, the liner  142  can be a nonwoven, spunbond polypropylene fabric composed of about 2 to 3 denier fibers formed into a web having a basis weight of about 12 gsm which is necked approximately 60 percent. Strands of about 9 gsm KRATON G2760 elastomer material placed eight strands per inch (2.54 cm) can be adhered to the necked spunbond material to impart elasticity to the spunbond fabric. The fabric can be surface treated with an operative amount of surfactant, such as about 0.6 percent AHCOVEL Base N62 surfactant, available from ICI Americas, a business having offices in Wilmington, Del., U.S.A. Other suitable materials may be extensible biaxially stretchable materials, such as a neck stretched/creped spunbond. Reference is made to U.S. Pat. No. 6,552,245, issued Apr. 22, 2003, to Roessler et al., which is incorporated by reference herein to the extent that it is consistent (i.e., not in conflict) herewith. 
     The absorbent core  91  includes absorbent material  26  and is suitably compressible, conformable, and capable of absorbing and retaining liquid body exudates released by the wearer. For example, the absorbent core  91  can include a matrix of absorbent fibers, and more suitably cellulosic fluff, such as wood pulp fluff, and superabsorbent particles. One suitable pulp fluff is identified with the trade designation CR1654, commercially available from U.S. Alliance, Childersburg, Ala., U.S.A. As an alternative to wood pulp fluff, synthetic fibers, polymeric fibers, meltblown fibers, short cut homofil bicomponent synthetic fibers, or other natural fibers may be used. Suitable superabsorbent materials can be selected from natural, synthetic, and modified natural polymers and materials. The superabsorbent materials can be inorganic materials, such as silica gels, or organic compounds, such as cross linked polymers, for example, sodium neutralized polyacrylic acid. Suitable superabsorbent materials are available from various commercial vendors, such as Dow Chemical Company of Midland, Mich., U.S.A., and Stockhausen Inc., Greensboro, N.C., U.S.A. 
     In various embodiments, the absorbent core  91  may include 30 to 90 percent superabsorbent by weight. In some embodiments, the absorbent core  91  may include at least 50, at least 60, at least 70, or at least 80 percent superabsorbent by weight. In various embodiments, the absorbent core  91  may include 70 to 10 percent cellulose fluff by weight. In some embodiments, the absorbent core  91  may include less than 70, less than 60, less than 50, less than 40, less than 30, or less than 20 percent cellulose fluff by weight. In some embodiments, the absorbent core  91  may include 50 to 90 percent superabsorbent material by weight and 50 to 10 percent cellulose fluff by weight. In some embodiments, the absorbent core  91  may include 60 to 90 percent superabsorbent material by weight and 40 to 10 percent cellulose fluff by weight. In some embodiments, the absorbent core  91  may include 70 to 90 percent superabsorbent material by weight and 30 to 10 percent cellulose fluff by weight. 
     The absorbent core  91  and/or the absorbent composite  90  may have a variety of shapes and configurations as are known in the art, such as rectangular, hourglass shaped, I-shaped, and the like. The absorbent core  91  may have the same shape or a different shape than the absorbent composite  90 . For example, the absorbent core  91  may have a rectangular shape and the absorbent composite  90  may have a rectangular shape. In another example, the absorbent core  91  may have an hourglass shape and the absorbent composite  90  may have a rectangular shape. 
     In some embodiments, the portions of the absorbent composite  90  including the absorbent core  91  may have a density within the range of about 0.10 to about 0.5 grams per cubic centimeter. The absorbent core  91  of the present invention may have a uniform density. In other words, the portions of the absorbent core  91  proximate the holes  41  may have essentially the same density as the portions of the absorbent core  91  more distant from the holes  41 . This uniform density is believed to provide for a soft and conforming absorbent composite  90  without hard spots or hard lines in the product. 
     Traditional cellulose fluff based absorbent products have been made thinner by greater compression resulting in higher densities and less flexibility. Alternatively, thinner absorbent products have been made with less absorbent material but may not have the absorbent capacity necessary to meet the needs of the wearer. However, as higher concentrations of superabsorbent materials have become more prevalent, thinner absorbent articles with adequate absorbent capacity have been manufactured. Unfortunately, absorbent articles with high concentrations of superabsorbent material have also traditionally suffered from structural breakdowns, superabsorbent shifting, and superabsorbent migration because the relative percentage of cellulose fluff “holding” the superabsorbent in place has decreased relative to the superabsorbent material contained therein. 
     In general, the method and apparatus of the present invention is compatible with relatively thin absorbent cores  91 . For example, in various embodiments, the absorbent core  91  and/or absorbent composite  90  can have a thickness of about 1 mm to about 10 mm. In some embodiments, the absorbent core  91  and/or the absorbent composite  90  may have a thickness of less than about 9 mm, less than about 8 mm, less than about 7 mm, less than about 6 mm, less than about 5 mm, less than about 4 mm, less than about 3 mm, or less than about 2 mm. The thin absorbent core  91  of the present invention allows for a thinner absorbent article. Thin absorbent articles are generally believed to be well suited for comfort and discretion. As used herein, the thickness of the absorbent composite  90  describes the thickness as measured in those portions including the absorbent core  91 . One skilled in the art will appreciate that portions of the absorbent composite  90  may not include the absorbent core  91  (for example, the marginal areas  42 ) and would obviously be thinner at these locations. 
     The present invention includes a thin absorbent composite having a stabilized absorbent core wherein structural breakdowns, superabsorbent shifting, and superabsorbent migration are believed to be limited. The stabilized absorbent composites include a first sheet joined to a second sheet at a plurality of bond points corresponding with a plurality of holes located within an absorbent core.  FIG. 9  representatively illustrates an exemplary absorbent composite  90 . Portions of the absorbent composite  90  are cut away in  FIG. 9  to illustrated underlying features.  FIG. 10  representatively illustrates the portion of  FIG. 9  delineated by box  10  and magnified for clarity and with portions cut away to illustrate underlying details.  FIG. 11  is a cross sectional view of the portion of the absorbent composite  90  illustrated in  FIG. 10 . 
     Referring now to  FIGS. 9 ,  10  and  11 , the absorbent composite  90  includes a first sheet  92 , a second sheet  93 , and a discrete unitary absorbent core  91  located therebetween. The absorbent core  91  has a plurality of holes  41  extending there through and is positioned between the first sheet  92  and the second sheet  93 . The first sheet  92  extends through the holes  41  in the absorbent core  91  and is joined with the second sheet  93  at a plurality of bond points  45 . The plurality of bond points  45  stabilize the absorbent core  91  and the absorbent composite  90 . Therefore, the resulting absorbent composite  90  includes a stabilized discrete unitary absorbent core  91  that is believed to be thin, soft, and compliant having no ridges, hard lines, or hard spots. 
     The unitary absorbent cores of the present invention have overall “continuity” (i.e., no segmenting) and are believed to promote free fluid movement throughout the entire core. The bond points are believed to improve the integrity of the absorbent composite, but the relatively small holes maintain a large absorbent area available to receive insults. Additionally, it is believed that the unitary absorbent cores with uniform densities will bend continuously and evenly about the wearer. Finally, it is believed that unitary absorbent cores will distribute the weight of the wearer more evenly and won&#39;t result in pressure points possible with discontinuous absorbent cores. 
     The holes  41  in the absorbent core  91  may have any suitable shape and any suitable size. For example, the holes  41  may have a circular shape, as illustrated in  FIG. 9 , but may alternatively be in the shape of an oval, square, triangle, or any other suitable geometric shape, irregular, or the like, or combinations thereof. In some embodiments, the absorbent cores  91  may have at least one first hole having a first shape and at least one second hole having a second shape wherein the first shape and the second shape are different. In some embodiments, the absorbent cores  91  may have at least one first hole having a first size and at least one second hole having a second size wherein the first size and the second size are different. 
     In various embodiments, the holes  41  may have a hole area  171  of 1 mm 2  (0.0015 in 2 ) to 200 mm 2  (0.3 in 2 ), 1 mm 2  (0.0015 in 2 ) to 100 mm 2  (0.155 in 2 ), or 1 mm 2  (0.0015 in 2 ) to 25 mm 2  (0.03875 in 2 ). In some embodiments, the hole area  171  may be less than 200 mm 2 , less than 100 mm 2 , less than 90 mm 2 , less than 80 mm 2 , less than 70 mm 2 , less than 60 mm 2 , less than 50 mm 2 , less than 40 mm 2 , less than 30 mm 2 , less than 20 mm 2 , or less than 10 mm 2 . In embodiments wherein the holes  41  have a generally circular shape, the holes  41  may have a diameter of 1 mm to 16 mm, 1 mm to 10 mm, or 1 mm to 5 mm. In some embodiments the holes  41  may have a diameter of less than 16 mm, less than 10 mm, or less than 5 mm. In various embodiments, the total area of the holes  41  may be between about 1 to about 33 percent, about 1 to about 25 percent, or less than about 10 percent of the total area of the absorbent core  91 . 
     In various embodiments, the absorbent cores may have at least one first hole having a first hole area and at least one second hole having a second hole area wherein the first and second hole areas are different. For example, in some embodiments, the absorbent cores may define a front portion generally oriented towards the front waist region of the absorbent article and a back portion generally oriented towards the back waist region of the absorbent article wherein the back portion includes holes having a larger hole area and wherein the front portion includes holes having a smaller hole area. 
     The absorbent material surrounding the holes  41  defines a hole wall  175 . The hole wall  175  is preferably no more or less dense than any other portion of the absorbent core  91  which is believed to be more comfortable to the wearer. In contrast, some traditional methods of stabilizing absorbent cores, such as pin aperturing, embossing, needling, and the like, have resulted in densified regions surrounding indentations. Such densifications may impact fluid movement within the absorbent core, may be noticeable to a wearer and/or caregiver, and may reduce the flexibility of the absorbent core  91 . 
     The bonds  45  may be any suitable shape and any suitable size. For example, the bonds  45  may be circular, as illustrated in  FIG. 10 , but may also be oval, square, triangular, or any other suitable geometric shape, irregular, or the like, or combinations thereof. In some embodiments, the absorbent cores  91  may have at least one first bond having a first shape and at least one second bond having a second shape wherein the first shape and the second shape are different. In some embodiments, the absorbent cores  91  may have at least one first bond having a first size and at least one second bond having a second size wherein the first size and the second size are different. 
     In some embodiments, the bonds  45  may have a bond area  173  of 1 mm 2  (0.0015 in 2 ) to 200 mm 2  (0.3 in 2 ), 1 mm 2  (0.0015 in 2 ) to 100 mm 2  (0.155 in 2 ), or 1 mm 2  (0.0015 in 2 ) to 25 mm 2  (0.03875 in 2 ). In some embodiments, the bond area  173  may be less than 200 mm 2 , less than 100 mm 2 , less than 90 mm 2 , less than 80 mm 2 , less than 70 mm 2 , less than 60 mm 2 , less than 50 mm 2 , less than 40 mm 2 , less than 30 mm 2 , less than 20 mm 2 , or less than 10 mm 2 . In embodiments wherein the bonds  45  generally have a circular shape, the bonds  45  may have a diameter of 1 mm to 16 mm, 1 mm to 10 mm, or 1 mm to 5 mm. In some embodiments the bonds  45  may have a diameter of less than 16 mm, less than 10 mm, or less than 5 mm. 
     In various embodiments, the absorbent cores  91  may have at least one first bond having a first bond area and at least one second bond having a second bond area wherein the first and second bond areas are different. For example, in some embodiments, the absorbent cores may define a front portion generally oriented towards the front waist region of the absorbent article and a back portion generally oriented towards the back waist region of the absorbent article wherein the back portion includes bonds having a larger bond area and wherein the front portion includes bonds having a smaller bond area. 
     In some embodiments, larger bonds and smaller bonds may be intermixed throughout the absorbent core in any suitable arrangement. In some embodiments, smaller bonds may be adapted to release when the absorbent material is wetted. In some embodiments, larger bonds may be adapted to remain joined when the absorbent material is wetted. 
     In some embodiments, the bond area  173  is at least 60, 70, 80, 90, or 95 percent that of the hole area  171 , resulting in an unbonded area  177  that is less than 40, 30, 20, 10, or 5 percent of the hole area  171 . It is believed that having the bond area  173  close to the same size as the hole area  171  results in greater stabilization of the absorbent core  91  because less of the absorbent material  26  is unsupported, i.e., there is less unbonded area  177 . For example, as illustrated in  FIG. 10 , the bond area  173  is approximately 60 percent of the hole area  171 , whereas the unbonded area  177  is about 40 percent of the hole area  171 . 
     In some embodiments, the bond area  173  may be substantially devoid of absorbent material  26 . In other words, the first sheet  92  may be joined directly to the second sheet  93  at the bond points  45  with substantially no absorbent material  26  therebetween. In some embodiments, the bond area  173  may be free of absorbent material  26 . In other words, the first sheet  92  may be joined directly to the second sheet  93  at the bond points  45  with no absorbent material  26  therebetween as illustrated in  FIG. 11 . 
     As illustrated in  FIG. 11 , the bonds  45  are skewed towards the second sheet  93 . As such, the first sheet  92  extends at least partially through the holes  41  of the absorbent core  91 . In some embodiments, the first sheet  92  extends entirely through the holes  41  of the absorbent core  91 . In one embodiment, the first sheet  92  may be positioned towards the liner  142  and the second sheet  93  may be oriented towards the outercover  140 . In another embodiment, the second sheet  93  may be positioned towards the liner  142  and the first sheet  92  may be oriented towards the outercover  140 . 
     In various embodiments, the bonds  45  may be generally located within the holes  41 . In some embodiments, the bonds  45  may be registered within the holes  41 . In other words, the bonds  45  may be generally centered within the holes  41 . For a bond  45  to be generally centered within the hole  41  means that the bonds  45  have a center point and the holes  41  have a center point and both center points coincide at common center point  179  as illustrated in  FIG. 10 . In some embodiments, at least 60, at least 70, at least 80, at least 90, and at least 99 percent of the bonds  45  are located with the holes  41 . In some embodiments, 100 percent of the bonds  45  are located within the holes  41 . In some embodiments, at least 60, at least 70, at least 80, at least 90, and at least 99 percent of the bonds  45  are registered within the holes  41 . In some embodiments, 100 percent of the bonds  45  are registered within the holes  41 . 
     In various embodiments, the absorbent composite may have a “bond point density” of 0.05 to 1.0 bond points  45  per square centimeter of absorbent core  91 . In some embodiments, the absorbent composite may have 0.1 to 0.5 bond points  45  per square centimeter of absorbent core  91 . In some embodiments, the absorbent composite may have 0.2 to 0.4 bond points  45  per square centimeter of absorbent core  91 . In some embodiments, the absorbent core  91  may have a first bond point density in a first region and a second bond point density in a second region. For example, the absorbent core  91  may have a front portion located generally towards the front waist region of the absorbent article and a back portion located generally towards the back waist region of the absorbent article wherein the front portion has a higher density of bond points and the back portion has a lower density of bond points. In some embodiments, the bond points  45  may have a diameter, D, and may be spaced apart by at least one times, two times, three times, or more than four times the diameter, D. 
     In various embodiments, the absorbent composite  90  may include an absorbent core  91  located between a liquid pervious first sheet  92  and a liquid pervious second sheet  93 . The liquid pervious first sheet  92  extends through holes  41  in the absorbent core  91  to join with the liquid pervious second sheet  93  at a plurality of bond points  45 . In various embodiments, the absorbent composite  90  may include an absorbent core  91  located between a liquid impervious first sheet  92  and a liquid pervious second sheet  93 . The liquid impervious first sheet  92  extends through holes  41  in the absorbent core  91  to join with the liquid pervious second sheet  93  at a plurality of bond points  45 . In various embodiments, the absorbent composite  90  may include an absorbent core  91  located between a liquid pervious first sheet  92  and a liquid impervious second sheet  93 . The liquid pervious first sheet  92  extends through holes  41  in the absorbent core  91  to join with the liquid impervious second sheet  93  at a plurality of bond points  45 . In various embodiments, the first sheet  92  or the second sheet  93  may face towards the liner  142 . 
     In one aspect, the absorbent composite  90  may be stretchable so as not to inhibit the stretchability of other components to which the absorbent composite  90  may be adhered, such as the outercover  140  and/or the bodyside liner  142 . For example, the absorbent composite  90  may include materials disclosed in U.S. Pat. Nos. 5,964,743, 5,645,542, 6,231,557, 6,362,389, and international patent application WO 03/051254, the disclosure of each of which is incorporated by reference herein to the extent that they are consistent (i.e., not in conflict) herewith. 
     In some aspects, a surge management layer (not shown) may be included in the diaper  120 . The surge management layer may be positioned in the diaper  120  in a variety of locations as is known in the art. For example, the surge management layer can be proximate the absorbent composite  90 , for example between the absorbent composite  90  and the bodyside liner  142 , and attached to one or more components of the diaper  120  by methods known in the art, such as by adhesive, ultrasonic bonding, pressure bonding, thermal bonding, and the like, or combinations thereof. 
     A surge management layer helps to decelerate and diffuse surges or gushes of liquid that may be rapidly introduced into the absorbent composite  90 . Desirably, the surge management layer can rapidly accept and temporarily hold the liquid prior to releasing the liquid into the storage or retention portions of the absorbent composite  90 . Examples of suitable surge management layers are described in U.S. Pat. No. 5,486,166 and U.S. Pat. No. 5,490,846, the contents of which are incorporated herein by reference to the extent that they are consistent (i.e., not in conflict) herewith. 
     While the invention has been described in detail with respect to specific embodiments thereof, it will be appreciated that those skilled in the art, upon attaining understanding of the foregoing will readily appreciate alterations to, variations of, and equivalents to these embodiments. Accordingly, the scope of the present invention should be assessed as that of the appended claims and any equivalents thereto.