Disposable absorbent article and absorbent core composite or construction for incorporation therewith, components therefor or thereof, and systems, apparatus and methods of making the same

Abstract

To provide a disposable absorbent article and an absorbent core composite or construction for incorporation therewith, components therefor or thereof, and systems, apparatus and methods of making the same.SOLUTION: Improved absorbent core components include multiple layers configured to enhance fluid handling properties. The layers include absorbent material layers, with or without absorbent material-free lanes. The layers also include nonwoven layers, including air-through nonwovens, bulkified nonwovens, slitted nonwovens, and bulky nonwovens.SELECTED DRAWING: Figure 23

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 62 / 646,870 (pending), filed March 22, 2018, which is incorporated herein by reference in its entirety and made a part of the present disclosure. This application also claims the benefit of U.S. Provisional Patent Application No. 62 / 646,875 (pending), filed March 22, 2018, which is incorporated herein by reference in its entirety and made a part of the present disclosure. This application also claims the benefit of U.S. Provisional Patent Application No. 62 / 646,880 (pending), filed March 22, 2018, which is incorporated herein by reference in its entirety and made a part of the present disclosure.

[0002] The present disclosure relates generally to disposable absorbent articles such as baby diapers, training pants, adult incontinence products, feminine hygiene articles, etc. More specifically, the present disclosure relates to improved absorbent core form elements, disposable absorbent articles utilizing such absorbent core form elements, and methods of making or manufacturing the same. [Background technology]

[0003] Most absorbent articles currently used as baby diapers have a construction similar to the absorbent article 10 shown in Figures 1A and 1B. Figures 1A, 1B, and 1C are reproduced from U.S. Patent Application Publication No. 2009 / 0129901. The conventional absorbent article 10 is shown in a flat, unfolded position in Figure 1A and in a cross-sectional view in Figure 1B. The absorbent article 10 includes an outer fluid-impermeable backsheet 101, a bodyside fluid-permeable nonwoven coverstock or topsheet 102, and an absorbent construct 110 positioned between the backsheet 101 and the topsheet 102. The absorbent core provides the main component of the absorbent construct 110 and is designed and positioned to receive and retain body fluids. The absorbent construct 110 may also include at least one fluid management, fluid distribution, and / or surge layer 103.

[0004] The backsheet 101 and the topsheet 102 together form or define the chassis or central body 105 of the absorbent article 10. The central body 105 can have a first longitudinal end edge 112a, a second longitudinal end edge 112b, and a longitudinal centerline YY extending through the central body 105 and bisecting the first and second end edges 112a, 112b. Left and right side edges 106a, 106b extend from one end edge 112a to the other end edge 112b. Each end edge 112a, 112b partially defines a waist region 113a, 113b of the central body 105, which is generally characterized as having a lateral width significantly greater than the lateral width of a central or crotch region 114 of the central body 105. The waist regions 113a, 113b are designed to allow the absorbent article 10 to be placed around the waist of a user. In this regard, the first and second waist regions 113a, 113b may be described as the front and back waist regions 113a, 113b, respectively. The conventional absorbent article 10 further includes fastening means 104 attached to each side of the rear waist region 113a. The fastening means 104 are stretchable so that they can be fastened to the corresponding side of the front waist region 113b. The fastening means 104 assist in holding the absorbent article 10 around and on the user's body. The absorbent article 10 also includes means 107 for elasticizing the absorbent article 10 to maintain closure and sealing around the user's legs. The elasticizing means 107 (e.g., leg cuffs and / or leg cutters) may be positioned along the longitudinal side edges 106a, 106b of the absorbent construct 110. Referring to FIG. 1A, a conventional absorbent construct 110 is centrally positioned in and around the crotch region 114 of the absorbent article 10 .

[0005] Currently, most diaper cores are made from a mixture of fibers and superabsorbent particles, specifically cellulose-based fibers made from wood pulp and superabsorbent particles (SAP) made from polyacrylic acid derivatives. An absorbent composite particularly suited for application in or with the disposable absorbent articles presented herein is described in U.S. Patent No. 6,275,999. SAP-nonwoven absorbent composites of the type disclosed in this patent are available in roll form for the diaper manufacturing process, allowing for much greater flexibility in absorbent core design. Nevertheless, because fluffed pulp-superabsorbent cores are typically provided as a continuous stream or web of absorbent material, the simpler and most cost-effective process requires that the absorbent core be maintained in a generally rectangular shape. These cores are typically formed into a rectangular shape designed for incorporation into absorbent articles. The core shape, particularly its width, is maintained in a dimension that accommodates placement within the diaper in the user's crotch area.

[0006] Furthermore, in many applications, it is preferable for the absorbent core to assume a generally hourglass shape. Such diaper cores are known in the art for providing a narrower crotch region that provides better fit and comfort to the user. The hourglass shape also provides wider regions at the longitudinal ends of the core, enhancing the diaper's absorbency and leakage control in the area above the central crotch region. FIG. 1C illustrates another prior art disposable absorbent article 10'. The absorbent article 10' employs a design in which the absorbent core 110' decreases in width in the crotch region 114' but is wider in the front and back waist regions 113a', 113b'. The result is an absorbent core 110' with a more hourglass-like shape. To achieve this desired hourglass-shaped core, rectangular absorbent core sections are cut from a continuous web of absorbent material and further shaped, particularly to form the narrower central region.

[0007] As is known in the art, the preferred diaper assembly process is a substantially linear, efficient, machine-guided process that produces large volumes of packaged product. Due to the disposable nature of consumer products, high-use items, and a plethora of competing and alternative products (e.g., reusable cloth diapers), maintaining a low cost for the final product is essential. Therefore, controlling the complexity of the manufacturing process and minimizing the number of steps and material waste is also essential. This presents technical challenges for those attempting to create alternative shapes and functionality to traditional disposable absorbent articles. For example, while hourglass-shaped diaper cores or cores with distinct zones of absorbency for some applications are generally desirable, additional cutting or forming steps or increased material costs may reduce the effectiveness of alternative designs. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] U.S. Patent Publication No. 2017 / 0224548 [Patent Document 2] U.S. Patent No. 6,540,853 [Patent Document 3] U.S. Patent No. 9,789,014 [Patent Document 4] US Patent Publication No. 2015 / 0045756 [Patent Document 5] U.S. Patent No. 8,785,715 [Patent Document 6] U.S. Patent No. 9,757,284 [Non-patent literature]

[0009] [Non-Patent Document 1] Dunstan and White, J. Colloid Interface Sci., vol. 111 (1986), p. 60 Summary of the Invention [Problem to be solved by the invention]

[0010] In any event, absorbent core configurations that ensure additional functionality and / or improved fit and comfort are desirable, but care must be taken to minimize material costs and manufacturing complexity. [Means for solving the problem]

[0011] Some embodiments include an absorbent core for incorporation into a disposable absorbent article. The absorbent core includes a first nonwoven, a second nonwoven, and an absorbent material. The absorbent material is positioned between the first nonwoven and the second nonwoven, embedded within the first nonwoven, embedded within the second nonwoven, or a combination thereof. At least one section of the second nonwoven includes a bulked nonwoven.

[0012] Another embodiment includes a system for bulking a nonwoven fabric, the system including a nonwoven fabric supply, a nonwoven fabric manipulator positioned to receive the nonwoven fabric from the nonwoven fabric supply and bulk the nonwoven fabric, and a collector positioned to receive the bulked nonwoven fabric from the nonwoven fabric manipulator.

[0013] Another embodiment includes a method of bulking a nonwoven fabric, the method comprising mechanically manipulating one or more surfaces of the nonwoven fabric, thermally manipulating one or more surfaces of the nonwoven fabric, or a combination thereof, and forming a bulked nonwoven fabric that exhibits a lower bulk density and a greater void volume than the nonwoven fabric.

[0014] Another embodiment includes an absorbent core comprising a first nonwoven layer, a second nonwoven layer bonded to the first nonwoven layer, a third nonwoven layer engaged to the second nonwoven layer opposite the first nonwoven layer, and an absorbent material embedded within the second nonwoven layer.

[0015] Another embodiment includes a method of making an absorbent core. The method includes depositing bicomponent fibers onto a nonwoven layer and forming a web of fibers. The fiber deposition forms a higher density region of bicomponent fibers at the bottom of the deposited web and a lower density population of bicomponent fibers at the top surface of the deposited web. The method includes depositing a SAP onto the web of fibers.

[0016] Another embodiment includes an absorbent core comprising a first nonwoven, a second nonwoven, an absorbent material positioned between the first and second nonwoven, embedded within the first nonwoven, embedded within the second nonwoven, or a combination thereof, and a loose fiber layer positioned between the first and second nonwoven.

[0017] Another embodiment includes a method of forming an absorbent core having a fibrous layer, the method including depositing loose fibers onto a first nonwoven layer and applying a second nonwoven layer over the loose fibers.

[0018] Another embodiment includes an absorbent core. The core includes a first nonwoven, a second nonwoven, and an absorbent material layer between the first and second nonwoven, the absorbent material layer including absorbent-containing lanes and absorbent-absent lanes. Embossing lines bond the first nonwoven to the second nonwoven. The embossing lines coincide with the absorbent-absent lanes such that the first nonwoven is embossed into the second nonwoven at locations corresponding to the absorbent-absent lanes.

[0019] Another embodiment includes a multi-layer absorbent core comprising a first bodyside nonwoven, a second nonwoven, a first layer of absorbent material positioned between the first and second nonwoven, embedded within the first nonwoven, embedded within the second nonwoven, or a combination thereof, and a third nonwoven, a second layer of absorbent material positioned between the second and third nonwoven, embedded within the second nonwoven, embedded within the third nonwoven, or a combination thereof.

[0020] These exemplary aspects and other aspects of the present disclosure are illustrated through the drawings identified and briefly described below and / or in the Detailed Description or appended claims. [Brief explanation of the drawings]

[0021] [Figure 1A] 1 is a schematic plan view of a prior art disposable absorbent article suitable for incorporating an absorbent core composite according to the present disclosure. [Figure 1B] 1 is a schematic cross-sectional view of a prior art disposable absorbent article suitable for incorporating an absorbent core composite or construction according to the present disclosure. [Figure 1C] 1 is a schematic plan view of a prior art disposable absorbent article suitable for incorporating an absorbent core composite according to the present disclosure; [Figure 1D] 1 is a perspective view of a disposable absorbent article that may incorporate an absorbent core composite according to the present disclosure. [Figure 1E] FIG. 1E is a plan view of the disposable absorbent article of FIG. 1D in a flat, stretched state. [Figure 1F] FIG. 1E is an exploded view of the disposable article of FIG. 1D. [Figure 2] FIG. 2 is a flat, unfolded plan view of a diaper with a portion of the top layer removed to reveal the location of a multi-layer absorbent core composite in accordance with the present disclosure. [Figure 3] FIG. 2 is a flat, unfolded plan view of a diaper with a portion of the top layer removed to reveal the location of a multi-layer absorbent core composite according to the present disclosure within the three-piece chassis of the diaper. [Figure 4] 1 is an exploded perspective view of a multi-layer absorbent core composite according to the present disclosure suitable for incorporation into a disposable absorbent core composite according to the present disclosure. [Figure 4A] 1 is a schematic cross-sectional view of a multi-layer core composite or construct according to the present disclosure comprising two absorbent core material layers. [Figure 4B] 1 is a schematic cross-sectional view of a multi-layer core composite or construct according to the present disclosure comprising three absorbent core material layers. [Figure 4C]1 is a schematic cross-sectional view of a multi-layer core composite or construct according to the present disclosure, comprising four absorbent core material layers, each layer underlying a nonwoven fabric layer. [Figure 4D] 1 is a cross-sectional view of a multi-layer core composite or construct including multiple layers of material of varying dimensions. [Figure 4E] 1 is a cross-sectional view of a multi-layer core composite or construct comprising multiple layers of material of varying dimensions (including thickness and depth). [Figure 4F] 1 is a cross-sectional view of a multi-layer core composite or construct including multiple layers of material of varying dimensions (including varying thickness, width, and / or depth). [Figure 4G] A cross-sectional view of a multi-layer core composite or construct including multiple layers of material of varying dimensions (including varying thickness, width, and / or depth) and an absorbent material layer characterized by absorbent material-free zones or lanes. [Figure 4H] A cross-sectional view of a multi-layer core composite or construct including multiple layers of material of varying dimensions (including varying thickness, width, and / or depth) and an absorbent material layer characterized by absorbent material-free zones or lanes. [Figure 4I] A cross-sectional view of a multi-layer core composite or construct including multiple layers of material of varying dimensions (including varying thickness, width, and / or depth) and an absorbent material layer characterized by absorbent material-free zones or lanes. [Figure 4J] FIG. 1 is an exploded perspective view of a multi-layer absorbent core composite or construct including an absorbent material layer having absorbent material-free lanes in the machine direction. [Figure 4K] FIG. 1 is a cross-sectional view of an absorbent core composite or construct having layers of varying content, basis weight, and arrangement that provide varying fluid flow and retention characteristics within and / or through the absorbent core composite or construct. [Figure 4L] FIG. 1 is a cross-sectional view of an absorbent core composite or construct having layers of varying content, basis weight, and arrangement that provide varying fluid flow and retention characteristics within and / or through the absorbent core composite or construct. [Figure 4M]FIG. 1 is a cross-sectional view of an absorbent core composite or construct having layers of varying content, basis weight, and arrangement that provide varying fluid flow and retention characteristics within and / or through the absorbent core composite or construct. [Figure 5] 1 is a schematic diagram of a system and process for making an absorbent core composite or construct according to the present disclosure. [Figure 6A] 1 is an exploded perspective view of a multi-layer absorbent core composite or construction having multiple layers of absorbent core material suitable for incorporation into a disposable absorbent core composite. [Figure 6B] FIG. 1 is an exploded perspective view of a multilayer absorbent core composite or construct suitable for incorporation into a disposable absorbent core composite, having at least one absorbent core material layer characterized by one or more absorbent material-free regions. [Figure 7A] FIG. 1 is a plan view of a discontinuous absorbent material layer featuring material-free zones. [Figure 7B] FIG. 1 is a plan view of a discontinuous absorbent material layer featuring material-free zones. [Figure 7C] FIG. 1 is a plan view of a discontinuous absorbent material layer featuring material-free zones. [Figure 7D] FIG. 1 is a plan view of a discontinuous absorbent material layer featuring material-free zones. [Figure 7E] FIG. 1 is a plan view of a discontinuous absorbent material layer featuring material-free zones. [Figure 7F] FIG. 1 is a plan view of a discontinuous absorbent material layer featuring material-free zones. [Figure 7G] FIG. 1 is a plan view of a discontinuous absorbent material layer featuring material-free zones. [Figure 8] FIG. 1 is an exploded perspective view of an absorbent core composite or construct having cross-direction (cross-direction) SAP-free lanes in an upper absorbent material layer and machine-direction (machine-direction) SAP-free lanes in a lower absorbent material layer. [Figure 9] FIG. 1 is an exploded perspective view of an absorbent core composite or construct having embossed lines aligned with SAP-free lanes. [Figure 9A]FIG. 1 is a front view of an absorbent core composite or construct in a flat configuration having embossed lines aligned with SAP-free lanes. [Figure 9B] FIG. 1 is a front view of an absorbent core composite or construct in a folded configuration having embossed lines aligned with SAP-free lanes. [Figure 10] FIG. 1 is an exploded perspective view of a multilayer absorbent core composite or construct including a slitted nonwoven layer aligned with, adjacent to, and positioned downstream of an absorbent material layer characterized by cross-directional absorbent material-free lanes suitable for incorporation into a disposable absorbent core composite. [Figure 11] 1 is a schematic perspective view of a system and process for applying an absorbent layer featuring absorbent material-free zones. [Figure 12] FIG. 10 is another schematic perspective view of a system and process for applying an absorbent layer featuring absorbent material-free zones. [Figure 13A] FIG. 1 is a front view of a multi-layer absorbent core composite or construction including a loose fiber layer. [Figure 13B] FIG. 1 is a front view of a multi-layer absorbent core composite or construction including a loose fiber layer. [Figure 13C] FIG. 1 is a front view of a multi-layer absorbent core composite or construction including a loose fiber layer. [Figure 14A] 1 is a schematic diagram of a system and process for providing a loose fiber layer. [Figure 14B] FIG. 1 is a schematic diagram of a loose fiber applicator. [Figure 15A] 1 is a photograph of a bulky nonwoven fabric before bulking. [Figure 15B] 1 is a photograph of a bulky nonwoven fabric after bulking. [Figure 15C] Photographs of a bulky nonwoven fabric before and after bulking are shown. [Figure 16A] FIG. 1 is a cross-sectional view of a bulky nonwoven fabric in which the bulk is increased in each section depending on whether or not SAP is used. [Figure 16B] FIG. 1 is a cross-sectional view of a bulky nonwoven fabric in which the bulk is increased in each section depending on whether or not SAP is used. [Figure 16C]FIG. 1 is a cross-sectional view of a bulky nonwoven fabric in which the bulk is increased in each section depending on whether or not SAP is used. [Figure 16D] FIG. 1 is a cross-sectional view of a bulky nonwoven fabric in which the bulk is increased in each section depending on whether or not SAP is used. [Figure 17] FIG. 1 is an exploded perspective view of a multi-layer absorbent core composite or construct including a lofted high loft nonwoven layer. [Figure 18A] 1 is a cross-sectional view of an example of an absorbent core composite or construct according to the present disclosure. [Figure 18B] 1 is a cross-sectional view of an example of an absorbent core composite or construct according to the present disclosure. [Figure 18C] 1 is a cross-sectional view of an example of an absorbent core composite or construct according to the present disclosure. [Figure 18D] 1 is a cross-sectional view of an example of an absorbent core composite or construct according to the present disclosure. [Figure 18E] 1 is a cross-sectional view of an example of an absorbent core composite or construct according to the present disclosure. [Figure 18F] 1 is a cross-sectional view of an example of an absorbent core composite or construct according to the present disclosure. [Figure 19A] 1 is a cross-sectional view of an absorbent core composite or construct including a bulked high loft nonwoven. [Figure 19B] 1 is a cross-sectional view of an absorbent core composite or construct including a bulked high loft nonwoven. [Figure 20] 1 is a schematic diagram of a system and process for bulking a nonwoven substrate in accordance with the present disclosure. [Figure 20A] FIG. 1 is a schematic diagram of an example of a brush suitable for use in bulking a nonwoven substrate. [Figure 20B] FIG. 1 is a schematic diagram of an example of a brush suitable for use in bulking a nonwoven substrate. [Figure 20C] FIG. 1 is a schematic diagram of an example of a brush suitable for use in bulking a nonwoven substrate. [Figure 20D] FIG. 1 is a schematic diagram of an example of a brush suitable for use in bulking a nonwoven substrate. [Figure 21] 1 is a photograph of an exemplary bulking system including a brush. [Figure 22A] 1 is a bar graph showing data collected during the bulking examples described herein. [Figure 22B] 1 is a bar graph showing data collected during the bulking examples described herein. [Figure 22C] 1 is a scanning electron microscope (SEM) image of fibers before bulking taken during a bulking example described herein. [Figure 22D] 1 is a scanning electron microscope (SEM) image of a fiber after bulking taken during a bulking example described herein. [Figure 23] FIG. 1 is a schematic diagram of a system and process for bulking a nonwoven substrate that includes both thermal and mechanical operations. [Figure 23A] FIG. 1 is a schematic diagram of a system and process for bulking a nonwoven substrate. [Figure 23B] FIG. 1 is a schematic diagram of a system and process for bulking a nonwoven substrate. [Figure 23C] FIG. 1 is a schematic diagram of a system and process for bulking a nonwoven substrate. [Figure 23D] FIG. 1 is a schematic diagram of a system and process for bulking a nonwoven substrate. [Figure 23E] FIG. 1 is a schematic diagram of a system and process for bulking a nonwoven substrate. [Figure 24] 1 is a schematic diagram of a system and process for making a multi-layer absorbent core composite or construct according to the present disclosure showing where bulking can be introduced. [Figure 25] FIG. 1 is a front view of an absorbent core composite or construct according to an aspect of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0022] The present disclosure generally provides disposable absorbent articles such as baby diapers, training pants, adult incontinence products, and feminine hygiene articles. More specifically, the present disclosure provides improved absorbent core form elements, disposable absorbent articles utilizing such absorbent core form elements, and methods of making or manufacturing the same.

[0023] Certain embodiments of the present disclosure are particularly directed to perfecting an absorbent core configuration that easily fits into conventional disposable absorbent articles and maintains comfort and fit for the user. Such absorbent core configurations, and disposable absorbent articles employing them, can be easily produced in large quantities without overburdening the manufacturing process with additional steps and material waste. In this regard, the present disclosure provides and presents more useful and flexible core configuration elements or components, and by incorporating these components into highly effective diapers and training pants, provides improved hourglass-shaped or near-hourglass-shaped core constructions.

[0024] In one embodiment, a disposable absorbent article is provided having a central body defining a first waist end region including a first longitudinal end edge, a second waist end region longitudinally spaced from the waist end region and including a second longitudinal end edge, and a crotch region positioned therebetween. An absorbent core composite is located between the end edges and includes at least one nonwoven layer and at least one absorbent material layer, optionally including at least one loose fiber layer. In some aspects, each nonwoven layer of the absorbent core composite is a slit nonwoven, a high-loft nonwoven (e.g., a breathable nonwoven), or a high-loft nonwoven (fully or section-lofted). The absorbent material layer may include SAP-free and SAP-containing lanes.

[0025] In some embodiments, the positions of the components of the absorbent core composites disclosed herein are arranged to impart desired fluid handling properties and functions to the absorbent core composite, such as fluid flow, fluid absorption, and fluid distribution properties and functions. The nonwoven and absorbent material layers within the absorbent core composite, the sections within each respective nonwoven or absorbent material layer, and the absolute and relative positions of sections within one layer relative to sections within another layer can be arranged to impart such desired fluid handling properties and functions. The positions of the nonwoven (NW), high-loft nonwoven (BNW), bulked high-loft nonwoven (BBNW), slit NW, SAP-containing layer, SAP-containing lane, and SAP-free lane can be selectively arranged within the absorbent core composite. Each of the various layers disclosed herein and their arrangements can be combined in various combinations to form various absorbent core composites according to the present disclosure. The absorbent core composites disclosed herein may comprise: (1) one or more nonwoven layers having various thicknesses, widths, lengths, SAP content, and SAP distribution among the various layers (e.g., as shown in and described with reference to Figures 4 and 4A-4S); (2) one or more absorbent material layers with or without SAP-free lanes (e.g., as shown in and described with reference to Figures 6A-9); (3) one or more nonwoven layers with slits (e.g., as shown in and described with reference to Figure 10); (4) one or more nonwoven layers with SAP-free lanes (e.g., as shown in and described with reference to Figure 11); (4) one or more nonwoven layers that are either fully or sectionally bulked (e.g., as shown in and described with reference to Figures 13A-13C), (5) one or more nonwoven layers that are either fully or sectionally bulked (e.g., as shown in and described with reference to Figures 15A-19B), (6) one or more bicomponent fibrous layers including high-density and / or low-density bicomponent fibrous layers (e.g., as shown in Figures 25 and 26), (7) one or more airlaid layers (e.g., as shown in Figures 25 and 26), or (8) any combination thereof. Any such absorbent core composite can be incorporated into an absorbent article such as that shown in and described with reference to Figures 1A-1F.

[0026] Some embodiments relate to systems and / or processes for forming any of the absorbent core composites or articles disclosed herein, which may incorporate (1) one or more of the features of the system shown in Figure 5, (2) one or more of the features of the system shown in Figure 11, (3) one or more of the features of the system shown in Figure 12, (4) one or more of the features of the system shown in Figure 14, (5) one or more of the features of the system shown in Figure 20, (6) one or more of any of the features of the device shown in Figures 20A-20C, (7) one or more of the features of the system shown in Figure 21, (8) one or more of the features of the system shown in Figure 23, (9) one or more of the features of any or all of the systems shown in Figures 23A-23E, (10) one or more of the features of the system shown in Figure 24, or (11) any combination thereof.

[0027] The absorbent core composites described herein can have high loft (promoting comfort and softer areas) and large void spaces from an otherwise flat core with little void volume. The increased void space or void volume functions to provide temporary fluid retention and transport space. Such spaces provide a place for fluid to temporarily reside within the boundaries during the time (a few seconds) it takes for the superabsorbent material to activate and absorb fluid. Such voids or spaces act to allow fluid flow and facilitate the dispersion of fluid secretions.

[0028] An advantageous application of the various concepts and embodiments of the present disclosure relates to baby diapers. For this reason, most of the exemplary discussion provided herein is directed to diapers. The present disclosure, of course, extends to applications other than diapers.

[0029] diapers FIG. 1D is a perspective view of a disposable absorbent article embodying the absorbent composite, FIG. 1E is a plan view of the disposable absorbent article of FIG. 1D in a flat, stretched state, and FIG. 1F is an exploded view of the disposable article of FIG. 1D. Referring to FIGS. 1D-1F, a disposable absorbent article in the form of a diaper 10 is shown. The diaper 10 includes a topsheet 50, a backsheet 60, and an absorbent core 46. The diaper 10 includes upstanding barrier cuffs 34 extending along its length and elasticated to conform to the buttocks of the wearer. In addition, the diaper 10 includes elastic bands 52 and fastening elements 26. The fastening elements 26 extend to and engage corresponding opposite edges of the diaper 10 to secure the diaper 10 around the wearer during use. The web structure shown in Figure IE can be subsequently cut, folded, sealed, welded, and / or otherwise manipulated to form the disposable diaper 10 into a finished or final configuration. To facilitate description of the diaper 10, the description will refer to a longitudinal axis AA, a laterally extending central axis BB, a pair of longitudinally extending side edges 90, and terminal edges 92 extending between the side edges 90. The diaper 10 includes a first end region or front waist region 12 along the longitudinal axis AA, a second end region or back waist region 14, and a crotch region 16 positioned therebetween. Each of the front and back waist regions 12, 14 is characterized by a pair of ear regions or ears 18 disposed on either side of the central body portion 20 and extending laterally from the side edges 90. A fastening structure 26 (e.g., conventional tape fasteners) is secured to each of the ears 18 along the back waist region 14 of the diaper 10. When the diaper 10 is worn about the waist, the front waist region 12 fits adjacent to the wearer's front waist region, the back waist region 14 fits adjacent to the back waist region, and the crotch region 16 fits around and under the crotch region. To properly secure the diaper 10 to the wearer, the ears 18 of the back waist region 14 are brought around and toward the front of the wearer's waist and into alignment with the ears 18 of the front waist region 12. The fastening surface can be located on or provided by an inner or outer surface of the front waist region 12.Alternatively, the fasteners 26 may be located on the ears 18 in the front waist region 12 and be securable to the ears 18 in the back waist region 14. The cuffs 34 may be provided with one or more spaced longitudinal elastic members 38. It will be noted below that any of these diaper elements or combinations of these elements may be assembled with or using any of the absorbent core composites disclosed herein. Additionally, an acquisition layer 48 may be added to improve performance.

[0030] The present disclosure, in part, relates to developing and utilizing alternative absorbent core designs that maintain or improve the comfort and fit of an absorbent article while also maintaining and improving the absorbency and seal of the core and absorbent article. Various embodiments of the present disclosure place particular emphasis on the selective placement and shaping of commercially available absorbent materials while maintaining cost-effectiveness and manufacturability of the resulting disposable absorbent article. In one aspect, emphasis is placed on the selective placement and variation of absorbent materials (i.e., absorbency profile) along the length and / or width to provide certain functionality and efficiency. The selected absorbency profile provides regions or areas within the resulting core construction that exhibit advantageous or optimal absorbency or absorbent function per unit area (sometimes referred to herein as "absorbency density" or "absorbent density"). As briefly mentioned above, various aspects of the present disclosure are particularly applicable to baby diapers (and also to training pants). For this reason, much of the description and illustrations herein are presented in the context of diapers. However, it will be apparent to one skilled in the art given the present disclosure that the present disclosure and its various aspects are also applicable to other disposable absorbent articles and absorbent core constructions, and therefore, the detailed description and illustration of embodiments of the present invention should not be construed as limiting the present disclosure.

[0031] 2 and 3 show a disposable absorbent article 20 in the form of a diaper and embodying various aspects of the present invention, including an improved absorbent core construction 210. The absorbent article 20 has a backsheet 201 (or 201a and 201b in FIG. 3) and a topsheet 202, which is shown in FIGS. 2 and 3 as being mostly removed to reveal the absorbent core construction 210. The combination of the backsheet 201 and topsheet 202 together help define a chassis or central body 205 of the absorbent article 20. Additionally, the central body 205 presents a first waist end region 213a including a first longitudinal end edge 212a (or simply the first end edge 212a), a second waist end region 213b including a second longitudinal end edge 212b (or the second end edge), and a longitudinal centerline YY that extends the length of the central body 205 and bisects the first end edge 212a and the second end edge 212b. The waist regions 213a, 213b can be identified by their respective portions of the absorbent article 20 and the central body 205 being positioned generally vertically over and around the thighs of a user when the absorbent article 20 is worn.

[0032] The central body 205 at least partially defines a crotch region 214 that is generally centered between the first waist region 213a and the second waist region 213b and about the lateral centerline XX. As is readily known to consumers and manufacturers alike, most of the crotch region 214 is positioned generally horizontally and / or curves upwardly when the article 20 is in an in-use state. The absorbent core composition 210 can center and support the crotch region 214 between the backsheet 201 and the topsheet 202. In such an arrangement, the absorbent core composition 210 is in a generally optimal position to receive body exudates when the absorbent article 20 is in an in-use state. The absorbent core construction 210 is also described herein as having a first longitudinal end 207a (or simply the first end 207a) and a second longitudinal end 207b (or the second end 207b) spaced longitudinally from the first end 212a and the second end 212b, respectively, of the central body 205. In some embodiments, the first and second ends 207a, 207b of the absorbent core construction 210 may not be clearly defined, for example, as edges, lines, or points. In such embodiments, the terms first and second ends are used to generally identify the edges of the absorbent construction or absorbent core that are longitudinally furthest away from the lateral centerline XX. In other embodiments, the first and second ends may be defined by multiple components or elements rather than by a single core-form element or element.

[0033] For ease of explanation and illustration, the absorbent core construction 210 will often be illustrated and described as consisting of only a layer of absorbent material, as shown in FIGS. 2 and 3 . Accordingly, the absorbent core construction 210 will be referred to herein simply as the absorbent core 210. As will be further apparent from the description of the various embodiments of this disclosure, the absorbent core 210 can be constructed of more than one individually attached core form element or absorbent core element, which can have significantly improved absorbency characteristics. The absorbent core 210 can be assembled from various combinations of nonwoven materials, absorbent fibers, and / or superabsorbent particles. The absorbent core can have characteristics or attributes (e.g., absorbency properties) that contribute to its particular overall design or function. As illustrated in other embodiments described in this Detailed Description, the absorbent core can take on widely different shapes and configurations.

[0034] The core element shapes can be formed and applied by any number of suitable means, including vacuum forming techniques, cutting with a rotary die, and cutting with a water jet device. Referring to Figure 3, the width of the absorbent core element 210 defines a first end 217a. When applied onto the absorbent article 20, each shape of the absorbent core 210 can be positioned in alignment with the longitudinal centerline YY of the absorbent article 20, with the end 217a located near one of the waist regions 213 of the central body 205. The absorbent core 210 is positioned centrally in the crotch region 214.

[0035] Referring to FIG. 2 , the absorbent core 210 can have a narrower midsection or central region (not shown) positioned near the lateral centerline XX in the crotch region 214. This narrowing of the central region means improved user comfort and compatibility with the leg-sealing components of the absorbent article 20. A greater amount of absorbent material per unit area can be present in the narrower central region to provide higher or greater absorbency in the portion of the absorbent core 210 having the greatest need for absorbency, forming the main absorbent region 250. The resulting absorbent core 210 can expand upward (not shown) from the crotch region 214 toward the front and back longitudinal ends 207 a, 207 b (i.e., upper absorbent regions). This greater expansion of core material increases the absorbent coverage in these upper regions of the absorbent core 210. The excess core material also helps seal the waist region 213 of the article 20 and prevent leakage therefrom.

[0036] With reference to Figure 3, for ease of discussion, the absorbent core 20 can be described as having a narrow central region or middle section M0 and a pair of end regions E1, E2 on either side of the middle section M0. The locations or boundaries of these regions are only generally defined (for purposes of discussion). In various embodiments, the main absorbent region 250 can be located substantially within the central region M0, but can extend longitudinally into the end regions E1, E2. Because the end regions E1, E2 are positioned generally above the middle section M0 when the absorbent article 20 is in use, these end regions are sometimes referred to as upper absorbent regions.

[0037] In some embodiments, the concentration of absorbent material increases or decreases along the longitudinal centerline YY from one waist end region 213a to the other waist end region 213b within the absorbent article 20. Thus, the longitudinal capacity profile of the article 20 can vary from one end 212a to the other end 212b. Thus, the absorbent construction can have significant variations in absorbency (per unit area (e.g., square inch) or absorbency density) along a specified direction or at a specified location on the central body 205. As discussed above, a higher concentration of absorbent material provides increased absorbency in the crotch region 214 of the absorbent article 20. While the absorbent article 20 can exhibit absorbency per unit area provided by the end regions E1, E2 of the core 210 near the waist regions 213a, 213b, this absorbency can be significantly reduced from that characterizing the main absorbent region 250. Nevertheless, the absorbent core 210 can extend upwardly sufficiently into the waist regions 213a, 213b to enlarge and extend the absorbent coverage of the article 20. Beyond the absorbent core 210, the absorbency (and absorbency per unit area) of the disposable absorbent article 20 predictably drops off.

[0038] In the description provided herein, the absorbent core can be described as a profiled core. In this regard, the description relates to the varying absorbency imparted to the absorbent article along a particular direction or at a specified location on the central body. Varying absorbency also refers to the varying physical contours of the resulting absorbent core, which is exemplified by the absorbent core profile. It should be noted that in some applications, variations in absorbency density can be achieved by using core materials with different absorbency characteristics instead of or in addition to core materials with substantially similar absorbency characteristics.

[0039] Optimal use of absorbent material is a key design consideration when developing the various configurations provided herein. Often, there is a conflicting balance between providing high absorbency within the article and maintaining low material costs. This requires control over use and control over the concentration of absorbent material to prevent clumping or clumping that impacts components against the user's skin, thereby reducing user comfort. If care is not taken, an irregular core profile can adversely affect the shape of the absorbent core when worn and can also lead to stress on the article's leak prevention features (e.g., elastic leg cuffs and leg gathers). Therefore, aside from cost considerations, the proposed absorbency profile is not simply the result of placing as much absorbent material as possible.

[0040] As discussed above, design requirements were those of manufacturability and ease of assembly. Very often, these attributes mean cost-effectiveness of the resulting product as well as high component quality. In this regard, the present disclosure accomplishes improved product designs, including configurations that provide specific absorbency characteristics and / or specific shapes without sacrificing or burdening manufacturability. One feature of the present disclosure that helps achieve these objectives is the use of multiple, substantially identical core elements to create a variety of core shapes, including irregular shapes (e.g., non-rectangular), and a variety of absorbency profiles. The selection of core elements also provides design and manufacturing flexibility.

[0041] As an example, the configuration and selection of the absorbent core composite and its constituent layers allows the manufacturer of the absorbent article 20 to easily modify or fine-tune the shape of the absorbent core 210 and the disposable absorbent article 20 by adjusting the position and size of the core 210. In this manner, the overall length of the absorbent core 210 can be adjusted to accommodate different sized absorbent articles. Such linear adjustments can be easily made during the substantially linear assembly process of the absorbent core. Furthermore, this adjustment allows for the creation of a desired lateral or longitudinal absorbency profile, including expanding or contracting the main absorbent region. The manufacturer can make further modifications to the absorbency profile and overall dimensions of the core by adjusting the length and width of the individual absorbent core elements.

[0042] definition For purposes of this description of various aspects of the present disclosure, an "absorbent core composite or construct" refers to an intimate arrangement of multiple components or sections, including one or more sections or components composed of or occupied by absorbent material. As with the term "composite," the term "construct" in some sense refers to such an intimate arrangement of multiple sections or components that together define an absorbent body or portion thereof. Such an absorbent body may be incorporated into a disposable absorbent article or disposable absorbent garment to form the absorbent core for the article. In some diaper or training pant applications, a cover layer (e.g., a nonwoven or nonwoven tissue) may encase or overlie the absorbent core (and this cover layer may be included in defining the absorbent core of the article). Additionally, the absorbent article may comprise one or more impermeable backsheets, one or more topsheets, one or more acquisition and distribution layers (ADLs), and / or one or more tissue layers surrounding or adjacent the absorbent core. As disclosed herein, an "absorbent core composite" comprises at least one nonwoven layer and at least one absorbent material layer. The "absorbent core composite" may also be referred to herein as an "absorbent core," "absorbent composite," "core composite," "absorbent core construct," "core construct," "core," or "absorbent core composite or construct."

[0043] As used herein, "NW" refers to nonwoven. Any nonwoven layer of the absorbent core composite disclosed herein may be a high-loft nonwoven, such as a ventilated nonwoven, including but not limited to a bulked nonwoven. At least some of the nonwoven layers disclosed herein may be meltblown (melt-blown) nonwoven, spunbound (spunbonded) nonwoven, or any combination thereof (e.g., spunbound-meltblown-spunbound (SMS) nonwoven). The nonwovens disclosed herein may also be air-laid nonwovens. Additionally, each nonwoven layer disclosed herein may be a "tissue" or "tissue layer," which is a cellulose-based (paper) nonwoven, as opposed to a synthetic nonwoven. The optional fibers of the nonwoven fabrics disclosed herein include, but are not limited to, fibers made of polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polylactic acid (PLA), other polyolefins, copolymers thereof, and any combination thereof, including bicomponent fibers. The fibers may be treated with a surfactant to modify the surface tension of the fibers so that they are hydrophilic. In some aspects, the NW layer used in the absorbent core composites disclosed herein is selected based on the pore size of the fabric, the fiber wettability of the fabric, or a combination thereof.

[0044] As used herein, the density of nonwovens, including high-loft nonwovens, is determined according to Equation 1: density (ρ) = mass (m) / volume (v) = mass / (length (l) x width (w) x thickness (t)). The International Nonwovens and Disposables Association (INDA) and the European Disposables and Nonwovens Association (EDANA) do not include a specific method for density, but provide test methods that allow one skilled in the art to arrive at a density value using Equation 1. Test method NWSP120.2.R0(15) set forth by INDA and EDANA provides a means for measuring the thickness (t) of high-loft nonwovens, also referred to as high-loft nonwovens. Test method NWSP130.1.R0(15) set forth by INDA and EDANA provides a means for measuring the mass per unit area or basis weight (bw). When the thickness and mass per unit area of ​​the bulky nonwoven fabric are determined in accordance with NWSP120.2.R0(15) and NWSP130.1.R0(15), the density can be determined according to the following equations 1 to 3. Equation 1 is density (ρ) = m / v = m / (l × w × t), equation 2 is mass per unit area (bw) = m / (l × w), and equation 3 is ρ = bw / t.

[0045] As used herein, "BNW" refers to "high loft nonwoven." High loft nonwovens are thicker than non-high loft nonwovens at low to medium basis weights. Breathable nonwovens are a type of high loft nonwoven and represent a manufacturing method for producing nonwovens in which hot air is passed through a carded nonwoven to thermally bond the fibers. Other types of high loft nonwovens include resin-bonded nonwovens and other carded nonwovens. A "high loft nonwoven," as referred to herein, is capable of forming an open fiber network or web of hydrophilic but non-absorbent fibers. Furthermore, as used herein, a high loft nonwoven is a nonwoven having a thickness between 100 μm and 10,000 μm (preferably 1,000 μm to 5,000 μm), a density of 15 g / m, or a thickness of 15 g / m. 2 and 200g / m 2 Between (preferably 20 g / m 2 and 80g / m2 Between 0.01g / cm 2 and 0.3 g / cm 2 Between (preferably 0.01 and 0.08 g / cm 2 The high-bulk nonwoven fabric is a fibrous web material having a density of between 300 μm and 2000 μm. Furthermore, the high-bulk nonwoven fabric has an effective pore size between 300 μm and 2000 μm. The effective pore size is estimated from the web density, fiber diameter, and fiber density values ​​according to the method of Dunstan and White in Non-Patent Document 1, where the effective pore size is 4×(1−solid volume fraction) / (solid volume fraction×solid density×solid specific surface area).

[0046] As used herein, "bulking" refers to a treatment and / or process that results in a decrease in the bulk density of a nonwoven fabric and an increase in the void volume and specific volume (i.e., the reciprocal of density) relative to the bulk density and void volume (porosity of the nonwoven web) of the nonwoven fabric before bulking. Such nonwoven fabrics after "bulking" are sometimes referred to herein as "bulked nonwoven fabrics."

[0047] As used herein, "BBNW" refers to a nonwoven, and optionally to a high loft nonwoven that has been at least partially bulked.

[0048] Any of the nonwoven fabrics disclosed herein can form the topsheet or cover layer of an absorbent core composite, the base layer, substrate, or backsheet of an absorbent composite, and the intermediate layer (positioned between the topsheet and backsheet) of an absorbent core composite, or any combination thereof.

[0049] As used herein, "nonwoven substrate" refers to any nonwoven fabric disclosed herein that supports at least some absorbent material thereon and / or therein.

[0050] As used herein, "SAP-free" and "absorbent material-free" refer to surface areas on a nonwoven substrate that lack absorbent material.

[0051] As used herein, "absorbent layer," "absorbent material layer," and "AML" refer to a layer of a core comprised of at least one absorbent material capable of absorbing and retaining at least some liquid. Any of the absorbent materials disclosed herein can be, or any of these absorbent materials can include, SAP (superabsorbent polymers or superabsorbent polymers), which can be comprised of, for example, polyvinyl alcohol, polyacrylate, grafted starch, or cross-linked sodium polyacrylate. Although described herein as particles, SAP can be in the form of particles, fibers, foams, webs, spheres, agglomerates of regular or irregular shapes, and films. In some aspects, SAP is combined with an absorbent matrix, which can be defibrated wood pulp or a similar material. In other embodiments, the SAP and absorbent core composite is entirely devoid of an absorbent matrix. In some aspects, at least one collection of SAP particles is mixed with at least one other particle. Such other non-SAP particles may include, but are not limited to, hot melt adhesive particles, binder particles, spacer particles, or other particles. While "SAP" is used to refer to absorbent material in many of the specific embodiments shown and / or described in this disclosure, it is understood that "SAP" in any such embodiment may be substituted with other absorbent materials. For example, a "no SAP lane" disclosed herein may be an "absorbent material-free lane." In some aspects, absorbent materials used herein are selected based on their inherent superabsorbent properties, including gel bed permeability, absorption rate (vortex), absorbent capacity (CRC), and particle size.

[0052] As used herein, "body side" or "body side" refers to the surface and / or side that faces the user's body when the absorbent core composite is worn by a user (e.g., when the absorbent core composite is incorporated into a diaper or other absorbent article worn by a user).

[0053] As used herein, "upstream" with respect to a process step refers to a step that occurs chronologically before another step in the process. For example, in a process in which a nonwoven fabric is bulked and then SAP is added to the bulked nonwoven fabric, the bulking step is described below as being "upstream" of the SAP addition step.

[0054] As used herein, "upstream," with respect to fluid flow within an absorbent core composite, refers to a spatial and / or temporal location along the fluid flow path. For example, if wetting fluid first flows through a lofted region of a nonwoven layer and then into a SAP-containing lane of the absorbent layer, the lofted region of the nonwoven layer will be described below as being "upstream" of the SAP-containing lane of the absorbent layer, at least with respect to this particular flow path.

[0055] Multilayer Core Some embodiments of the present disclosure include multilayer absorbent cores comprising one or more nonwoven layers and one or more absorbent layers. In some such embodiments, the multilayer absorbent cores comprise layers with varying lengths, widths, thicknesses, basis weights, SAP loadings, material compositions, densities, the presence or absence of SAP-free lanes, wettability, capillary action, SAP permeability, SAP absorption rate, SAP absorption capacity, NW void volume, NW capillary action, and / or the presence or absence of slits. In some embodiments, these same properties can be varied within a single layer. The relative and relative arrangement and properties of these layers can be selected to provide desirable fluid flow and retention characteristics. For example, the relative and relative arrangement and properties of these layers can be selected to allow fluid to rapidly flow into and into the bodyside of the core, thereby maintaining the bodyside of the core in a relatively dry and comfortable condition.

[0056] The exploded view of FIG. 4 illustrates a multilayer absorbent core composite or construct 410 according to the present disclosure and suitable for incorporation into a disposable absorbent core composite also according to the present disclosure. Such composites or constructs may be referred to herein by the acronym MLC. As will be apparent to those skilled in the art, a multilayer composite or construct according to the present disclosure includes at least one fiber network layer (FNL or NW) and at least one absorbent material layer having absorbent material disposed therein. In some applications, the absorbent material layer may include two or more individual, often spaced apart, deposits or agglomerates of absorbent material located between two nonwoven or fiber network layers. The individual deposits or agglomerates need not necessarily be identical. These deposits or agglomerates may not necessarily be at the same depth and thickness (in the z-direction), but will generally be found between two separate layers or components and will generally be found at or about the same approximate depth.

[0057] Accordingly, various applications and aspects of the present disclosure are defined by the combination of the above-described basic components with one or more material or structural features described or exemplified in this disclosure, including this Detailed Description, Summary, Drawings, and Claims. Therefore, this Detailed Description, Summary, individual Drawings, or Claims should not be construed as limiting these aspects and applications. Instead, each of these portions of the present disclosure specifies one or more structural or material features that can be combined or combined with the above-described basic components to define a unique aspect or application. Furthermore, the basic components can be added to or incorporated into various disposable absorbent articles, each according to an aspect of the present disclosure. The same applies to systems, apparatus, and methods for making absorbent composites and disposable absorbent articles incorporating the same. That is, systems, apparatus, and methods for making the above-described various absorbent composites (including the subsystems and sub-steps applied to the steps of creating or constructing the components) are also specified herein and provided in accordance with the aspects and applications of the present disclosure.

[0058] Returning to the multilayer composite MLC of FIG. 4, two absorbent material (AM) layers (sometimes referred to herein simply as SAP layers and referred to as "SAP" in the figures), each preferably comprising or consisting of superabsorbent particles (SAP), are utilized. The two AM layers are bound together and at least partially supported by a nonwoven fabric layer comprising two breathable layers (AT) and one SMS layer. In FIG. 4 and the remaining cross-sectional views (unless otherwise indicated), the top layer (in this case the top AT layer) is positioned above the first SAP layer and functions to receive any initial fluid discharges or infiltrations, and may therefore be referred to as body-facing, body-facing, or upstream of other components. The first or top SAP layer may be characterized by an absence of SAP (or absorbent material absence, AM absence, or simply "absent lane") oriented in the longitudinal or y-direction of the diaper or core plane. This direction corresponds to the direction from one waist region or waist end region to the opposite (oppositely positioned) waist region or waist end region. The y-direction also refers to the plane when the article or core is unfolded in a flat state, i.e., before being worn or later in the manufacturing process. However, it is important to understand that when the article is worn, an article including such a core surface or core plane will curve to conform to the wearer's body. Thus, the waist region and longitudinal ends or longitudinal regions of the core are elevated relative to the infiltration point, the crotch region of the article, and the central portion of the absorbent core (all juxtaposed at or before or after the low point of curvature of the core). For reference, see, e.g., Figures 1D-1F, 2, and 3.

[0059] In the construction of Figure 4, the top bodyside AM layer is below the top bodyside NW or AT layer. The bodyside AT layer acts to assist in the acquisition and distribution of the initial fluid intake. A second AT layer is positioned between the top bodyside AM layer and the bottom AM layer, and a bottom SMS layer is positioned below the bottom AM layer. In use, the absorbent core 410 concentrates distribution functions and mechanisms upstream of the top layer or early during fluid wetting and acquisition. In one embodiment, the top and / or bottom AM layers are a single, homogenous construction (i.e., have no AM-free lanes). The bottom AM layer receives fluid that has passed through the top layer and dissipated from the SAP-filled or saturated SAP region of the top AM layer.

[0060] Although each AM layer, AT layer, and SMS layer in Figure 4 is shown as a separate layer, the absorbent core composites or constructs disclosed herein are not limited to such an arrangement, and some layers can at least partially overlap in the z-direction. For example, AM1 can be at least partially or completely embedded within AT1, within AT2, or within AT1 and AT2 (optionally, completely embedded within a combination of AT1 and AT2). When an AM layer is completely embedded within an AT layer (or other nonwoven layer), the AM and AT layers completely overlap in the z-direction. AM2 can be at least partially or completely embedded within AT2, within the SMS, or within AT2 and SMS (optionally, completely embedded within a combination of AT2 and SMS).

[0061] Multi-tier core - two centralized SAP layers Similar to the core described with reference to FIG. 4, each AM layer of FIGS. 4A-4S can be at least partially or completely embedded within one or more adjacent nonwoven layers (e.g., NW or BNW).

[0062] 4A is a schematic cross-sectional view of a multilayer core composite or construct 410a including two absorbent core material layers AM1 and AM2 and two lofty nonwoven layers BNW1 and BNW2. In some aspects, AM1 and AM2 are homogeneous SAP layer constructs with no AM-free lanes. In one embodiment, AM1 and AM2 each have a basis weight of 150 gsm, and BNW1 and BNW2 each have a basis weight of 50 gsm. Thus, 150 gms of SAP is concentrated within the two layers of MLC 410a.

[0063] Multi-layer core - three distributed layers of SAP 4B is a schematic cross-sectional view of a multilayer core composite or construct MLC 410b having three absorbent core material layers AM1, AM2, and AM3 (each of which may have a fill factor of 100 gsm) and three high-loft nonwoven layers BNW1, BNW2, and BNW3 (each of which may have a fill factor of 50 gsm). Thus, the overall basis weight (and raw material cost) of the components is the same between constructs 410a and 410b, but the SAP is distributed in thinner layers between the higher-loft nonwoven layers. The BNW layers provide a larger area for fluid distribution in the Y and X directions, and there is more SAP to receive fluid (as opposed to concentrations of SAP that may saturate more quickly), thereby improving the effectiveness and efficiency of the absorbent core.

[0064] Multi-layer core - four distributed layers of SAP FIG. 4C shows yet another illustration of the benefit of spreading the same amount of SAP in a thinner layer sandwiched between more BNW layers. In this case, MLC 410c uses four AM layers, including AM1, AM2, AM3, and AM4 (each of which may have a 75 gsm fill factor), and four BNW layers, including BNW1, BNW2, BNW3, and BNW4 (each of which may have a 25 gsm fill factor). This arrangement results in the same total component basis weight as cores 410a and 410b, with the same raw material cost. However, MLC 410c has a larger BNW area that acts to acquire and distribute liquid more easily than a smaller BNW area. Similarly, in MLC 410c, the SAP is spread out more widely compared to the SAP spread in MLCs 410a and 410b, allowing the SAP in MLC 410c to more easily receive and absorb fluid inhalants. By spreading out more, the SAP can present a larger surface area to the fluid infiltrate for more efficient absorption of the fluid infiltrate. Likewise, the additional lofty nonwoven area more efficiently receives, entangles, and / or embeds the SAP particles, thereby more efficiently inhibiting migration of such particles during manufacturing, packaging, use, etc. (See U.S. Patent Nos. 5,629,992 and 5,729,992, for further discussion of SAP entanglement in lofty nonwovens, which are incorporated herein by reference for all purposes).

[0065] That is, in some aspects, the present disclosure relates to methods of distributing set amounts of SAP and BNW into multiple layers within an absorbent core composite, as opposed to incorporating additional SAP and BNW into the absorbent core composite. Thus, enhanced fluid management functionality can be achieved without increasing the basis weight of the core composite and without increasing the raw material costs associated with forming the core composite.

[0066] Multilayer Core - Varying Dimensions In some aspects, each layer of the absorbent core composite may vary in length, width, height, or a combination thereof. Figure 4D is a cross-sectional view of a multilayer core composite or construct MLC410d including multiple material layers of varying dimensions. This example configuration uses three lofty nonwoven layers BNW1, BNW2, and BNW3 with varying thicknesses and three AM layers AM1, AM2, and AM3 with varying thicknesses. The thicker BNW layers are the top layer (BNW1) and the middle layer (BNW2), with the bottom BNW layer (BNW3) being the thinnest. Conversely, the top AM layer (AM1) is the thinnest of the AM layers in MLC410d, while the middle layer (AM2) and bottom layer (AM3) are thicker and of approximately the same thickness. Thus, the thicker BNW layers BNW1 and BNW2 are precisely positioned to act on fluid intake near the wetting point, including distributing it in the x and y directions (e.g., through the intracapillary migration action of the fiber network). See the directional arrows in Figures 4J, 4Q, 4R, and 4S, which indicate the point or region of initial intake or initial wetting and show fluid distribution through the fiber network within cores 410j, 410q, 410r, and 410s. Figure 4D also illustrates other components commonly incorporated into absorbent core composites of the same type as disclosed herein (and the absorbent core or crotch region of disposable absorbent articles). Article A can include a cover layer CL and a base layer BL (not shown) that substantially encase absorbent core composite MLC 410d and form part of the absorbent core. Also shown are a topsheet TS and an impermeable backsheet BS. An ADL layer may be included (not shown) on top of the absorbent core composite MLC 410d.

[0067] 4E and 4F are cross-sectional views illustrating variations in multilayer core composites or constructs MLC410e and MLC410f, respectively, according to the present disclosure. Each of MLC410e and MLC410f includes multiple material layers of varying dimensions, including varying thicknesses and depths (height in the z-direction). MLC410e in FIG. 4E includes four BNW layers and four AM layers. These BNW layers have a gradually decreasing thickness from the top to the bottom layer. Conversely, the AM layers increase in thickness from the top to the bottom layer. The thicker BNW layer BNW1, which serves as the top layer, presents a softer surface to the user while also utilizing and maximizing the ADL function of the BNW. The BNW layers are wider in the x-direction than the AM layers. Therefore, the gradient thickness of the BNW layers in MLC410e is the inverse of the gradient thickness of the AM layers in MLC410e. The MLC 410f in Figure 4F features a top BNW layer BNW1 and an AM layer of reduced width (and length) relative to the lower BNW layers. The top two layers, centrally positioned in the crotch region of the disposable absorbent article A, function as an initial reception or target zone for fluid inhalation. The reduced dimensions reduce raw material usage due to reduced material along the lateral side edges, while providing a more conforming profile to the wearer and increased flexibility (around the length).

[0068] Multilayer core with vertically aligned SAP-free lanes Figure 4G shows a cross-sectional view of a multilayer core composite or construct MLC410g, which includes multiple layers of material with varying dimensions, including thickness, width, and depth. The MLC410g includes five absorbent material layers (in the machine direction), with absorbent material-free zones or lanes FL in the top four AM layers AM1-AM4. As discussed above with respect to Figure 4, the lanes are located near the center and the central AM layer or stack. The lanes facilitate the transport of fluid intake along the y-direction, along which the greater extent of the absorbent material is located. The lanes also facilitate the transport of fluid within the absorbent core composite MLC410g to lower levels (and further to the absorbent material). FLs are also positioned on the side edges. When the lanes are vertically aligned, fluid can easily and rapidly flow from one FL through the adjacent BNW layer to the downstream FL below it, from the body side at or near the TS toward the backside BS.

[0069] Multilayer core with staggered SAP-free lanes The multilayer core composite or construct MLC 410h of Figure 4H is similar to that of Figure 4G. However, the AM-free lanes FL are not vertically aligned between the various layers of MLC 410h. Instead, in each downwardly successive AM layer within MLC 410h, except for the bottom AM layer, the free lanes are positioned laterally outward. Arranging the free lanes in this manner accommodates further distribution of fluid intake outward with each successive downstream layer within composite 410h.

[0070] Figure 4I is a cross-sectional view of a multi-layer core composite or construct 410i including multiple layers of material of varying dimensions, including thickness, width, and depth, including an absorbent material layer characterized by absorbent material-free zones or lanes FL. The composite 410i of Figure 4I uses some of the features of the previous multi-layer core construct, including alternating AM-free lanes FL.

[0071] Multilayer core - Fluid flow guidance Figure 4J is an exploded perspective view of a multilayer absorbent core composite or construct 410j including an absorbent material layer with absorbent-material-free lanes in the machine-machine direction according to the present disclosure. The fiber network layer in this exemplary composite MLC 410j is provided by a high-loft nonwoven having an upper BNW layer (NW1), a middle layer (NW2), and a base layer (NW3). The AM1 layer, including the SAP-free lanes FL, has a short length compared to the NW layer and AM2. AM1 is positioned in a central or target region of the absorbent article and is supported on, within, and / or between NW1 and NW2. The arrows in Figure 4J indicate the XY extent of fluid flow into the MLC 410j, including within the SAP layers, AM1, and AM2. The directionality of such fluid flow is generally controlled, at least in part, by SAP permeability and absorption rate, which are tailored to be slower than the corresponding fluid flow in the NW layer and SAP-free lanes. In some aspects, to support fluid capillary movement during use, all of the nonwoven layers in the area designated "B" of MLC 410j in FIG. 4J are designed to be regions of high capillarity compared to the portion of the nonwoven layers in the area designated "A" of MLC 410b.

[0072] In use, the absorbent core composite can have a U-shaped configuration. In some aspects, the absorbent core composite layers are arranged and configured such that SAPs with high permeability and / or slower absorption rates are positioned in the uppermost, body-facing, top layer, and faster SAPs are positioned in the lower, higher-capacity, bottom layer. Thus, when worn by a user, low-capillarity region A is positioned in the crotch region and is lower on the body compared to high-capillarity regions positioned higher on the user's waist. Thus, the higher capillarity in region B promotes intracapillary movement of fluid from region A to region B, even against gravity. The flow pattern indicated by the arrows in Figure 4J addresses flow in the longitudinal direction (y-direction) of the product and refers to embodiments with a capillarity gradient (higher capillarity toward the edges of the absorbent product) to support intracapillary movement of fluid against gravity. These arrows indicate that fluid spreads within the SAP layer at a generally slower rate than fluid spreads in the NW and SAP-free lanes.

[0073] Multi-layer core - basis weight variation 4D-4I, each article A includes a top sheet TS and a back sheet BS. The top sheet TS may be a hydrophilic, water-permeable layer (e.g., a spunbound nonwoven fabric) having a thickness of 15 g / m 2 or 5g / m 2 from 20g / m 2The topsheet BS can have a basis weight of 1 / 2 lb. Such a topsheet can be used with any of the absorbent core composite embodiments disclosed herein. The backsheet BS can be a water-permeable layer (e.g., a polyethylene film and a multi-layer laminate of a nonwoven and a polyethylene film). Such a backsheet can be used with any of the absorbent core composite embodiments disclosed herein. The basis weight of each nonwoven layer and the fill factor (basis weight) of each absorbent layer can vary, with these layers and their basis weights being selected and positioned to provide desired fluid intake, distribution, and absorption characteristics (collectively "fluid handling properties"). For example, in some embodiments, the basis weight of the nonwoven decreases, on average, as one moves downward in the z-direction into the core, and the basis weight (fill factor) of the absorbent material increases as one moves downward in the z-direction into the core. Referring now to Figures 4D-4I, various exemplary arrangements of nonwoven layers and absorbent layers having selected basis weights are described below.

[0074] The MLC 410d in FIG. 4D is wrapped in a top sheet TS and a back sheet BS, and has a weight of 30 g / m 2 from 60 g / m 2 and a top BNW1 layer which is a breathable nonwoven fabric having a basis weight that can range from 30 g / m 2 from 80g / m 2 and a middle BNW2 layer, which is a breathable nonwoven fabric having a basis weight that can range from 20 g / m 2 from 50g / m 2 and a bottom BNW3 layer, which is a breathable nonwoven fabric with a basis weight that can range from 50 g / m to 100 g / m. MLC410d is sandwiched between BNW1 and BNW2 and is 50 g / m 2 from 150 g / m 2 and sandwiched between BNW2 and BNW3, with a basis weight of 75 g / m 2 from 200 g / m 2 and BNW3, with a basis weight of 75 g / m 2 from 200 g / m 2and an AM3 layer having a basis weight of 1000 sq. m. Each of the AM layers can comprise or consist of SAP. As can be seen in Figure 4D, the nonwoven layers BNW1, BNW2, and BNW3 are wider in the x-direction than the absorbent material layers AM1, AM2, and AM3.

[0075] FIG. 4E shows an article A having a top sheet TS and a back sheet BS with an absorbent core composite MLC410e wrapped therein. The MLC410e has a 30 g / m 2 from 60 g / m 2 and a top BNW1 layer which is a breathable nonwoven fabric having a basis weight that can range from 30 g / m 2 from 50g / m 2 a first intermediate BNW2 layer which is a breathable nonwoven having a basis weight that can range from 20 g / m 2 from 40 g / m 2 a second intermediate BNW3 layer which is a carded nonwoven having a basis weight that can range from 20 g / m 2 from 40 g / m 2 and a bottom BNW4 layer that is a carded nonwoven with a basis weight that can range from 30 g / m to 100 g / m. MLC410e is sandwiched between BNW1 and BNW2 and has a basis weight of 30 g / m. 2 from 100g / m 2 and sandwiched between BNW2 and BNW3, with a basis weight of 50 g / m 2 from 150 g / m 2 and sandwiched between BNW3 and BNW4, with a basis weight of 50 g / m 2 from 150 g / m 2 and BNW4, with a basis weight of 75 g / m 2 from 200 g / m 2and an AM4 layer having a basis weight of 1000 sq. m. Each AM layer can comprise or consist of SAP. As is evident from FIG. 4E , the nonwoven layers BNW1, BNW2, and BNW3 are wider in the x-direction than the absorbent material layers AM1, AM2, and AM3. Similarly, the thickness of the nonwoven layers exhibits a continuous gradation such that it decreases from the proximal TS to the BS, while the thickness of the absorbent layers exhibits a continuous gradation such that it increases from the proximal TS to the BS (i.e., the gradient of the nonwoven layers is opposite to the gradient of the absorbent material layers).

[0076] FIG. 4F shows an article A having a top sheet TS and a back sheet BS with an absorbent core composite MLC410f wrapped therein. The MLC410f has a 30 g / m 2 from 60 g / m 2 and a width of 80 mm, which is narrower than the other layers; and 2 from 50g / m 2 a first intermediate BNW2 layer which is a breathable nonwoven fabric having a basis weight of 20 g / m2 and a width of 105 mm; 2 from 40 g / m 2 a second intermediate BNW3 layer which is a breathable nonwoven fabric having a basis weight ranging from 20 g / m to 105 mm and a width of 105 mm; 2 from 40 g / m 2 and a width of 105 mm. MLC410f is sandwiched between BNW1 and BNW2 and has a basis weight of 30 g / m 2 from 100g / m 2 and sandwiched between BNW2 and BNW3, with a basis weight of 50 g / m 2 from 150 g / m 2 and sandwiched between BNW3 and BNW4, with a basis weight of 50 g / m 2 from 150 g / m 2 and BNW4, with a basis weight of 50 g / m 2 from 100g / m 2and an AM4 layer having a basis weight of 1. The top nonwoven layer BNW1 is narrower than the remaining nonwoven layers, and the top absorbent material layer AM1 is narrower than the remaining absorbent material layers. Each AM layer can comprise or consist of SAP.

[0077] FIG. 4G shows an article A having a top sheet TS and a back sheet BS with an absorbent core composite MLC410g wrapped therein. The MLC410g has a density of 20 g / m 2 from 50g / m 2 and a top BNW1 layer which is a breathable nonwoven fabric having a basis weight that can range from 20 g / m 2 from 50g / m 2 a first intermediate BNW2 layer which is a breathable nonwoven having a basis weight that can range from 20 g / m 2 from 50g / m 2 a second intermediate BNW3 layer which is a breathable nonwoven having a basis weight that can range from 20 g / m 2 from 50g / m 2 a third intermediate BNW4 layer which is a breathable nonwoven having a basis weight that can range from 30 g / m 2 from 80g / m 2 and a bottom BNW5 layer, which is an air-laid nonwoven having a basis weight of 30 g / m. MLC410 g is sandwiched between BNW1 and BNW2, 2 from 100g / m 2 and sandwiched between BNW2 and BNW3, with a basis weight of 30 g / m 2 from 100g / m 2 and sandwiched between BNW3 and BNW4, with a basis weight of 50 g / m 2 from 150 g / m 2 and sandwiched between BNW4 and BNW5, with a basis weight of 50 g / m 2 from 150 g / m 2 and BNW5, with a basis weight of 50 g / m 2 from 150 g / m 2and an AM5 layer having a basis weight of 1000 sq. m. Each AM layer can comprise or consist of SAP. Each of the MLC410g nonwoven layers has the same or substantially the same thickness, whereas the AM layer exhibits a graded thickness such that it thickens toward the BS.

[0078] FIG. 4H shows an article A having a top sheet TS and a back sheet BS with an absorbent core composite MLC410h wrapped therein. The MLC410h has a 20 g / m 2 from 50g / m 2 and a top BNW1 layer which is a breathable nonwoven fabric having a basis weight that can range from 20 g / m 2 from 50g / m 2 a first intermediate BNW2 layer which is a breathable nonwoven having a basis weight that can range from 20 g / m 2 from 50g / m 2 a second intermediate BNW3 layer which is a breathable nonwoven having a basis weight that can range from 20 g / m 2 from 50g / m 2 a third intermediate BNW4 layer which is a breathable nonwoven having a basis weight that can range from 20 g / m 2 from 50g / m 2 The bottom layer BNW5 is a breathable nonwoven fabric having a basis weight of 30 g / m. The MLC410h is sandwiched between BNW1 and BNW2 and has a basis weight of 30 g / m. 2 from 100g / m 2 and sandwiched between BNW2 and BNW3, with a basis weight of 30 g / m 2 from 100g / m 2 and sandwiched between BNW3 and BNW4, with a basis weight of 50 g / m 2 from 150 g / m 2 and sandwiched between BNW4 and BNW5, with a basis weight of 50 g / m 2 from 150 g / m 2 and BNW5, with a basis weight of 50 g / m 2 from 150 g / m 2and an AM5 layer having a basis weight of 1000 sq. m. Each AM layer can comprise or consist of SAP. Each of the MLC410g nonwoven layers has the same or substantially the same thickness, whereas the AM layer exhibits a graded thickness such that it thickens toward the BS.

[0079] FIG. 4I shows an article A having a top sheet TS and a back sheet BS with an absorbent core composite MLC410i wrapped therein. The MLC410i has a 20 g / m 2 from 50g / m 2 and a narrow width of 70 mm (the remainder of the BNW has a width of 95 mm); and 2 from 50g / m 2 a first intermediate BNW2 layer which is a breathable nonwoven having a basis weight that can range from 20 g / m 2 from 50g / m 2 a second intermediate BNW3 layer which is a breathable nonwoven having a basis weight that can range from 20 g / m 2 from 50g / m 2 a third intermediate BNW4 layer which is a breathable nonwoven having a basis weight that can range from 20 g / m 2 from 50g / m 2 The bottom layer BNW5 is a breathable nonwoven fabric having a basis weight of 30 g / m. The MLC410i is also sandwiched between BNW1 and BNW2 and has a basis weight of 30 g / m. 2 from 100g / m 2 and sandwiched between BNW2 and BNW3, with a basis weight of 30 g / m 2 from 100g / m 2 and sandwiched between BNW3 and BNW4, with a basis weight of 50 g / m 2 from 150 g / m 2 and sandwiched between BNW4 and BNW5, with a basis weight of 50 g / m 2 from 150 g / m 2 and BNW5, with a basis weight of 50 g / m 2 from 150 g / m 2 and an AM5 layer having a basis weight of

[0080] In Figures 4 and 4A-4I (as well as any other core composites disclosed herein), the absorbent material in each of the AM layers can be composed of the same or different polymers (e.g., SAPs) that impart the same or different configurable and stackable fluid management properties to each layer. Similarly, AM-free lanes (FL) can be provided within any of the AM layers of the composites disclosed herein. Furthermore, the positioning of multiple AM-free lanes, if any, can be aligned to promote fluid flow toward selected core regions, e.g., toward the lower and outer core regions. In Figures 4H and 4I, the AM-free lanes FL are positioned with little overlap between AM-free lanes in adjacent layers, thereby promoting fluid flow toward the side edges of the core and the lower regions of the core. While Figures 4 and 4A-4I do not show adhesive, adhesive can be used to adhere the nonwoven layers to each other and / or to adhere the absorbent material to the nonwoven layers.

[0081] In some embodiments, the nonwoven layer disclosed herein has a fiber density of 20 g / m 2 from 80g / m 2 , 30g / m 2 from 60 g / m 2 , 30g / m 2 from 80g / m 2 , 20g / m 2 from 50g / m 2 , 20g / m 2 from 40 g / m 2 , or 30 g / m 2 from 50g / m 2 In some embodiments, the absorbent material layer disclosed herein has a basis weight ranging from 30 g / m 2 from 200 g / m 2 , 50g / m 2 from 150 g / m 2 , 75g / m 2 from 200 g / m 2 , or 30 g / m 2 from 100g / m 2 The sheet has a basis weight of .

[0082] In one particular embodiment, the absorbent core composite has a density of 75 g / m 2 and a top bulky nonwoven layer having a basis weight of 150 g / m 2 a bottom airlaid nonwoven layer having a basis weight of 30 g / m 2 and a single intermediate high loft nonwoven layer having a basis weight of 150 g / m. The top nonwoven layer and the intermediate high loft nonwoven layer can be constructed of the same or substantially the same material but with different fill rates (e.g., different thicknesses). In this particular embodiment, the absorbent core composite includes two absorbent material layers, including a top absorbent material layer sandwiched between (and optionally embedded within) the top high loft nonwoven layer and the intermediate high loft nonwoven layer, and a bottom absorbent material layer sandwiched between (and optionally embedded within) the bottom airlaid nonwoven layer and the intermediate high loft nonwoven layer. Each of the two absorbent material layers has a basis weight of 150 g / m. 2 and may include or consist of SAP. In some applications, a nonwoven having a relatively high basis weight on the body side of the core composite has been found to promote fluid absorption and distribution into the lower portion of the core, thereby improving dryness of the body side of the core.

[0083] Multilayer core - Fluid flow guidance 4K-4M show the fluid flow direction and paths within and through composites 410k, 410l, and 410m. Fluid is distributed incrementally toward the side edges and bottom of the core, with AM-free lanes promoting and directing fluid flow within the core as shown.

[0084] Common core structure method To achieve certain desirable or enhanced fluid or waste handling (flow and retention) functions in many of the core constructs disclosed herein, attention can be directed to the selection and subsequent strategic placement of absorbent materials, including the use of additives (see, e.g., Figures 18E and 18F) and / or fiber webs or nonwovens to affect target properties. In this regard, relevant inherent superabsorbent properties include gel bed permeability, absorption rate (vortex), absorbent capacity (CRC), particle size, particle packing density, and stiffness, among others. Additionally, relevant inherent fiber web layer (nonwoven) properties include density (i.e., void volume (=1 / density)) and capillarity (pore size and fiber wettability).

[0085] Regarding material placement within the core composite, certain general principles can be applied to more general applications. In general, SAPs positioned in the wetting path of fluid flow in the z-direction (thickness) have the following characteristics: (1) gradient permeability, with the highest permeability at or near the top of the core and decreasing lowest at or near the bottom of the core; (2) gradient absorption rate, with slow absorption SAPs positioned at or near the top of the core and progressively faster SAPs positioned at or near the bottom of the core; and (3) gradient absorption capacity, with high absorption capacity SAPs positioned at or near the bottom of the core for maximum absorption efficiency and low absorption capacity SAPs positioned at or near the top of the core.

[0086] The fiber network layer (e.g., nonwoven layer) in the path of infiltration of the flow fluid in the z-direction (thickness) typically exhibits a gradient void volume, with a high void volume nonwoven at or near the top of the core and a low void volume nonwoven at or near the bottom of the core, to handle the initial fluid infiltrate jet and distribute this fluid within the NW layer. Similarly, the core can exhibit profiled or gradient capillary action in the xy plane within the fiber network layer, with higher capillary action (relative to the fluid target area) toward its ends. Such a capillary action profile allows the fluid to spread continuously toward the ends of the core for full utilization.

[0087] Variation in capillarity between and within layers can be achieved through selective densification, enhanced wetting through plasma or corona treatment (of regions in the xy plane), increased loft, or the selective placement of pre-existing lofty and less lofty layers. Multiple fiber network layers in the z direction can be selected and designed to exhibit and exhibit layers of increased capillarity toward the bottom (downstream) and layers of decreased capillarity toward the body. Such a capillarity gradient promotes and / or facilitates the capillary movement of fluid flow downstream toward the bottom AM layer, promoting fluid spreading against gravity (i.e., when the article is worn and positioned in a U-shape), thereby increasing the availability of absorbent material and core during product use. It should be noted that more absorbent material and absorbent surface are found in the y direction, causing the absorbent article to curve generally upward toward the waist region or longitudinal ends of the article during wear. Therefore, the progress of fluid toward the waist region may be resisted by gravity.

[0088] System for forming a multilayer core Figure 5 is a schematic diagram of a system and process for making an absorbent core composite or construction according to the present disclosure. In Figure 5, "BNW Unwind" refers to a machine roller or spool that unwinds a BNW fibrous web for combination with other elements to form an absorbent core composite, "C1" refers to a compression device such as a pair of opposing machine rollers that apply a compressive force to a fabric passing therebetween, "Adhesive" refers to an applicator that applies adhesive to a passing fabric and / or layer of absorbent material, "SAP Applicator" refers to an applicator that applies SAP to a passing fabric and / or layer of absorbent material, and "Final Unwind" refers to a collection spool onto which the formed absorbent core composite is collected after production.

[0089] System 500 includes BNW unwinder 1, from which BNW 1 is unwound and passed through C1 for compression. From C1, BNW 1 passes under adhesive 1, where adhesive is applied to BNW 1. From adhesive 1, BNW 1 passes over roller 502, and then SAP is applied to BNW 1 from SAP application unit 1. In some embodiments, at least some of the SAP penetrates BNW 1.

[0090] System 500 includes BNW unwinder 2, from which BNW 2 is unwound and passes over roller 504 and under adhesive 2, where adhesive is applied to BNW 2. From adhesive 2, BNW 2 passes over roller 506. Further, from SAP application 1, BNW 1 passes over roller 506, whereby BNW 1 and BNW 2 are laminated together at or after roller 506 to form laminate 508.

[0091] From roller 506, laminate 508 passes under SAP applicator 2, where SAP is applied to laminate 508. In some embodiments, at least some of the SAP penetrates laminate 508. From SAP applicator 2, laminate 508 passes over roller 510.

[0092] System 500 includes BNW unwinder 3, from which BNW 3 is unwound and passed through C1 for compression. From C1, BNW 3 passes over roller 512 and under adhesive 4, where adhesive is applied to BNW 3. From adhesive 4, BNW 3 passes over roller 514 and then over roller 516. Laminate 508 also passes over roller 516, whereby BNW 3 and laminate 508 are laminated together at or after roller 516 to form laminate 518.

[0093] Laminate 518 then passes through rollers 520 and under SAP applicator 3, where SAP is applied to laminate 518 and some of the SAP is allowed to permeate laminate 518. Laminate 518 then passes over rollers 522 and 524.

[0094] System 500 includes BNW unwinder 4, from which BNW 4 is unwound and passed through C1 for compaction. From C1, BNW 4 passes over roller 526 and under adhesive 5, where adhesive is applied to BNW 3. From adhesive 5, BNW 4 passes over roller 528 and over roller 524. BNW 4 and laminate 518 are laminated together at or after roller 524 to form laminate 530.

[0095] Laminate 530 passes through roller 532 and under SAP application station 4, where SAP is applied to laminate 530 and some of the SAP is allowed to permeate laminate 530. Laminate 530 then passes over roller 534 and roller 536.

[0096] System 500 includes BNW unwinder 5, from which BNW 5 is unwound and passed through C1 for compaction. From C1, BNW 5 passes over roller 538 and under adhesive 6, where adhesive is applied to BNW 5. From adhesive 6, BNW 5 passes over roller 540 and over roller 536. BNW 5 and laminate 530 are laminated together at or after roller 536 to form laminate 542.

[0097] The stack 542 passes through rollers 544 and reaches a final payout point for collection of the stack 542 .

[0098] Of course, the system shown in Figure 5 is for illustrative purposes only, and other system configurations and system arrangements can be used to form any number of core composite configurations according to the present disclosure.

[0099] No SAP Lane - Machine Direction and / or Cross Direction In some embodiments, one or more of the absorbent material layers include absorbent material-free lanes (e.g., SAP-free lanes). Although referred to as "lanes," such SAP-free areas can be of any number of shapes and configurations and can extend in the machine direction, the cross direction, or any other direction or pattern. Although referred to as "SAP-free," such lanes or areas can be free of any absorbent material or at least SAP. In some aspects, the number of machine-direction SAP-free lanes in the top AM layer is greater than the number of machine-direction SAP-free lanes in the underlying and / or bottom AM layers. In some embodiments, only the top AM layer has machine-direction SAP-free lanes. In some embodiments, only the top AM layer has any SAP-free lanes. Incorporation of SAP-free lanes into the absorbent core composite improves softness (increasing compressibility), increases fluid uptake rate, reduces fluid bleed-through and spill-over from the AM layers, and directs and distributes fluid flow within the core.

[0100] Referring to FIG. 6A, a multilayer absorbent core composite 610a is shown having multiple absorbent core material layers, including an upper SAP layer, AM1, with SAP-free lanes oriented in the machine direction. Additionally, composite 610a uses a breathable high-loft nonwoven as the upper and middle layers. An SMS nonwoven layer forms the base layer. Without being bound by theory, it is believed that having two or more SAP-free lanes, FL, in the machine direction further improves fluid distribution over having a single SAP-free lane in the machine direction. In some aspects, as shown, only the upper AM layer (AM1) has SAP-free lanes, while the lower AM layer (AM2) has no SAP-free lanes, thereby improving fluid retention within the lower AM layer. In some embodiments, SAP-free lanes can be provided along the side edges and / or edges of the AM layer to enable sealing (adhering the AM layers above and below it).

[0101] In the configuration of Figure 6A, three consecutive SAP deposits are spaced apart to form SAP-free lanes FL. These lanes are elongated spaces or voids bounded by the depth profiles of adjacent SAP-containing lanes. Because such elongated voids (and even tall SAP deposits at some points) resemble machine-direction lanes on a conveyor during manufacturing, the term "lane" is appropriately used herein. SAP "free" can be used to refer to a portion of the substrate where SAP is not specifically deposited and is bounded by elongated regions where absorbent material is continuously deposited. It should be further noted that the substrate onto which SAP (and the SAP-free lanes) are applied is typically the underlying NW or AT layer. The intermediate SAP deposit SAP2 of AM1 is wider than the two outer SAP deposits (SAP1 and SAP3), primarily because it will sometimes be positioned to coincide with the wetting point or initial receiving area (target zone). The intermediate SAP deposit SAP2 is wide enough (or the SAP-free lanes are narrow enough) to reliably contain the fluid inlet. The SAP-free lanes FL are positioned close enough to the central target zone to receive significant fluid intake and aid in distribution along the z-direction (against gravity) toward and along the greater portion of the SAP that cannot, at least initially, receive its share of the fluid intake. Of course, the AT layer also influences and assists in initial intake acquisition and distribution. To promote NW-to-NW bonding (without interfering with or from the SAP), the SAP-free lanes FL are preferably aligned with embossed or bond lines and patterns. In FIG. 6A , the outer SAP lanes SAP1 and SAP3 are made at least about one-third or one-quarter narrower than the middle SAP stack SAP2 to provide SAP-free areas near the lateral side edges. This helps seal and maintain the side edges during manufacturing and subsequent packaging and use. The SAP-free lanes near the top layer are also believed to improve the softness and flexibility of the absorbent core.Note that the absorbent core will curve slightly sideways and also upwards when worn, so SAP-free lanes near the upper surface improve flexibility, for example, around the longitudinal axis oriented through it. Many of the benefits of having SAP-free lanes in the upper SAP layers are at least partially diminished for the bottom SAP layer. In use, the core can concentrate distribution functions and mechanisms upstream in the upper layers or early at the wetting and acceptance points. Thus, in one embodiment, the bottom SAP layer can have a single, uniform composition (i.e., no SAP-free lanes). This SAP layer accepts fluids traveling through the upper layers, including fluids traveling downward from the upper SAP-free lanes and fluids dissipating from the SAP-filled or saturated SAP regions.

[0102] In the embodiment shown in Figure 6B, the multilayer composite 610b uses a SAP layer with cross- or transversely absent lanes. AM1 includes multiple SAP-free lanes FL. The SAP-free lanes and the SAP deposits or agglomerates between them can be uniformly spaced and of the same width throughout the series of absent or SAP lanes. Screen or wire printing, vacuum drum printing, or SAP printing can be used to deposit the SAP in the cross direction.

[0103] In some aspects, machine-direction and cross-direction absence lanes are combined within a single core composite and / or a single AM ​​layer to form complex patterns of SAP and SAP-free regions (e.g., grid patterns). Figures 7A-7G show various configurations of AM layers featuring AM-free lanes. Some configurations feature absence lanes only in the cross direction ( Figures 7B, 7F ), whereas others are equipped with absence lanes only in the machine direction ( Figures 7C, 7D ). Other configurations feature a combination of absence lanes in both the cross direction and the machine direction ( Figures 7A, 7E ). The configuration shown in Figure 7G utilizes absence lanes oriented at an angle (i.e., neither longitudinally nor laterally oriented). These variations also illustrate that AM deposits or agglomerates sharing an AM layer with the absence lanes may be of various widths, lengths (and depths), and shapes dictated by the absence lanes that bound them. The corresponding use of SAP lanes also facilitates constructing core composites, SAP layers, and absorbent surfaces with varying properties (as a function of location and depth). Each absorbent material lane or aggregate or SAP region can be constructed with an absorbent material or material mixture that exhibits targeted properties and improves certain fluid performance. For example, SAPs with higher absorbency or certain additives or higher raw material costs can be concentrated or confined within the central portion of the core composite.

[0104] Each AM layer configuration provides sufficient absorbent material located in areas corresponding to the target zone or wetting point. This ensures easy acceptance and absorption of fluid inhalants. The cross-directional non-existent lanes of FIG. 7B also improve the flexibility of the core composite around the longitudinal axis. In yet another embodiment, additional SAP aggregates or SAP lanes can be added near the lateral side edges to cover the cross-directional lanes, preventing a straight path to the side edges. Such multilayer core constructions may be particularly adapted for use in certain feminine napkin products, etc.

[0105] The configurations of Figures 7A and 7E utilize cross-direction and machine-direction absence lanes to create a lattice of absence lanes. These lattice configurations exploit the operational and structural benefits of using both types of structures as AM layers, particularly near the top surface of the composite. These benefits include greater fluid distribution, greater flexibility, and improved user comfort. The inclusion of multiple AM ​​agglomerates, particularly in the case of Figure 7E where the agglomerates are of varying shapes and sizes, allows for the design of absorbent surfaces with varying properties across the extent of the layer. Absorbent materials, with or without additives, can be selected and concentrated in agglomerates (and composites) that occupy specific targeted areas of the AM layer.

[0106] 7E further features machine-machine direction non-existent lanes with absorbent material provided in the end regions where the non-existent lanes terminate. The aggregates of absorbent material deposited on these end regions act as fluid barriers to fluid movement along the non-existent lanes, reducing the risk of leakage. These strategically placed aggregates also provide a point of arrival for absorbent material for such fluid movement within the non-existent lanes. Depending on the product and purpose of the absorbent article, these aggregates in the end regions can be sized differently and have a different composition than the other aggregates.

[0107] The grid or pattern of absorbent material aggregates shown in FIG. 7G is not limited to the use of cross-direction and machine-direction free lanes. In some variations, the free lanes or regions are linear pathways, thus resembling lanes, particularly in manufacturing processes. The purpose of the grid pattern in FIG. 7G is to efficiently and substantially distribute the fluid aspirate to the absorbent material (preferably in a non-sequential manner). In this design, the pathways cover a larger area. The pathways along the y-direction are provided by two main free lanes that are wider and longer than the other free lanes. Additional arteries of SAP free lanes are provided to extend fluid movement to other absorbent material areas without requiring free lane redirection. The result is more comprehensive coverage; that is, more fluid is guided linearly to more absorbent material using the momentum of the fluid aspirate (e.g., without relying as much on capillary action or capillary flow). Moreover, the absorbent aggregates remain as a continuous deposit, where the fluid has continuous two- or three-dimensional pathways in most areas and access to adjacent, preferably unsaturated, absorbent material (e.g., SAP particle to SAP particle). The lattice morphology of Figure 7G and other configurations are suitable for SAP printing techniques. Such techniques would further enable greater compositional control of absorbent material deposits and patterns, as well as specific and precise placement of absorbent material. Lattice configurations can also be formed through the use of movable obstacles, suction aids, specific target placements, and the like.

[0108] In some aspects, the SAP is applied onto the nonwoven layer using particle scattering methods such as gravure rolls, needle rolls, or by providing the SAP on a damped vibration channel. The machine-direction lanes of SAP can be formed by closing off sections of the SAP scattering means so that the SAP scattering devices do not fully open across the entire potential application area on the nonwoven. Closing off sections of the SAP scattering devices can be permanent or fixed. In some aspects, the SAP scattering devices can be selectively openable or closed, such as by opening and closing apertures. Opening and closing the SAP scattering devices allows for the length of the machine-direction SAP lanes to be discontinuous or intermittent.

[0109] The cross-direction SAP-free lane can be formed by intermittently turning the SAP applicator on and off. When the SAP applicator is on, the cross-direction SAP-containing lane is not formed from side to side of the nonwoven substrate material. When the SAP applicator is off, the cross-direction SAP-free lane is formed from side to side of the nonwoven substrate material. In some aspects, the cross-direction SAP-free lane is formed by opening and closing an opening, where the closure spans the entire width or a substantial portion of the width of the SAP applicator.

[0110] In some aspects, the SAP can be continuously applied to the patterned shell under vacuum (e.g., onto a nonwoven substrate positioned above the patterned shell). Sections of the patterned shell may not be under vacuum, or the vacuum suction can be blocked or interrupted in such sections so that the SAP does not attach to the patterned shell (or the nonwoven thereon) in such sections. Although some SAP particulates may be lost in the vacuum, this application method can form a well-defined SAP pattern.

[0111] SAP-free lane - selective placement within the upper layer for fluid flow In some aspects, at least one absorbent material layer of the absorbent core composite disclosed herein includes a SAP-free lane, and at least another absorbent material layer of the absorbent core composite does not include a SAP-free lane. In some aspects, it is advantageous to include a SAP-free lane in the top, bodyside absorbent material layer of the absorbent core composite, but not in the bottom absorbent material layer. Such an arrangement of SAP and SAP-free lanes can facilitate rapid fluid absorption in the absorbent core composite by fluidly communicating fluid flow from the upper layer of the core to the lower layer of the core.

[0112] SAP-free lane-to-lane variation In some aspects, the SAP-containing lanes can vary in at least some respects. For example, the SAP-containing lanes can vary in the size of the SAP particles contained therein, the type and / or composition of the SAP particles contained therein, the concentration of SAP particles contained therein (e.g., amount of SAP per area of ​​nonwoven substrate), the addition or absence of non-SAP particles in the SAP-containing lanes, the width, length, and / or height (in the x-, y-, and z-directions) of the SAP-containing lanes, and the type and / or state of the nonwoven substrate (e.g., NW, BNW, BBNW, slit NW) supporting the SAP within the SAP-containing lanes. In some aspects, the SAP-free lanes and the SAP-containing lanes can be selectively positioned on the nonwoven substrate to provide fast-absorbing SAP at the side edges of the absorbent core composite and slow-absorbing SAP in the center / crotch region of the absorbent core composite.

[0113] In some aspects, the SAP-free lanes are empty except for the nonwoven substrate that forms them, hi other embodiments, at least one of the SAP-free lanes contains particles and / or fibers of non-absorbent material.

[0114] SAP-free lanes - combinations of different SAP layers In some aspects, different absorbent material layers comprising machine-direction SAP-free lanes and cross-direction SAP-free lanes can be positioned within a single absorbent core composite. For example, the absorbent core composite can include at least three absorbent material layers having a top (body-facing) upper absorbent material layer with machine-direction SAP-free lanes, a middle absorbent material layer with cross-direction SAP-free lanes, and a bottom absorbent material layer with a uniform SAP layer with no SAP-free lanes.

[0115] The AM layers shown in Figures 6A, 6B, and 7A-7G can be used as any of the AM layers in any of the absorbent core composites disclosed herein.

[0116] SAP-free lanes in different tiers FIG. 8 shows a combination of SAP layers, one with AM1 cross-direction absent lanes FL and the other with AM2 machine-direction absent lanes FL. In some embodiments, the upper SAP layer AM1 will feature machine-direction absent lanes so that the initial, larger volume of fluid intake is rapidly distributed to other parts of the core by the available SAP. The lower SAP layer AM2 can also be equipped with machine-direction absent lanes for the same reason. However, in yet another variation, the lower SAP layer can be equipped with cross-direction absent lanes for other reasons. In some applications, the absorbent core composite can have an upper layer and an ADL layer that functions well enough to easily distribute the initial fluid intake in the z-direction. In this case, the lower SAP layer can function to distribute the fluid received by flowing into the lower level in the y- and x-directions. It is anticipated that in this case, such fluid volume may not be significant and may not be concentrated in the central region. Additionally, the cross-direction non-existent lanes in the bottom layer provide some added flexibility about the longitudinal axis (i.e., the lateral side edges can more easily rotate to conform to the user's body during wear). As shown, the core 810 includes a top breathable nonwoven, a bottom SMS layer, and a middle nonwoven layer that is a slitted nonwoven. The slitted nonwoven disclosed herein can be the same as or substantially similar to that disclosed in U.S. Patent Application Publication No. 2007 / 0129990, all of which are incorporated herein by reference.

[0117] SAP-free lanes aligned with embossing lines FIG. 9 shows a compensation effect 910 including embossed lines EL that bond (e.g., adhere) adjacent nonwoven layers. The core 910 includes a top breathable layer AT and an embossed middle breathable layer AT sandwiching AM1. AM1 includes a SAP-containing lane and a SAP-free lane. The core 910 also includes a bottom nonwoven SMS sandwiching AM2. The top and middle AT layers are embossed, and the SAP-free lane FL of AM1 is aligned with the embossed lines (EL) of the top and middle AT layers so that these AT layers are bonded to each other without adding adhesive to the SAP, which can harden the SAP and sometimes reduce its absorbency. That is, the top AT layer, along with the middle AT layer, is embossed only in locations that correspond to the FL lane of AM1. Furthermore, the alignment of the SAP-free lane with the embossed lines provides bend or fold lines within the core 910, which facilitates fit by improving the flexibility of the core when worn by a user.

[0118] When the embossing lines coincide with the SAP-free lanes, the core 910 has the ability to bend / fold without disturbing the absolute and relative positions of the SAP and without disturbing the absorbent properties of the SAP (by forcing the SAP particles closer together). Thus, the embossing / folding / bending lines allow the core 910 to move from a flat configuration to a folded and / or bundled configuration as worn by a user. As shown, the embossing / folding / bending lines EL extend parallel to the longitudinal extension of the core 910. In some embodiments, at least one embossing / folding / bending line coincides with the longitudinal centerline of the core 910.

[0119] FIG. 9A shows a schematic diagram of core 910 in a flat configuration, and FIG. 9B shows a schematic diagram of core 910 in a bent or folded configuration, bent at location 912 along the core where lateral side edges 913 are promoted upward to coincide with the EL of core 910.

[0120] When the absorbent core 910 incorporated into an absorbent article is worn by a user, forces imparted by the user's body to the absorbent core 910 can cause contraction and / or folding of the absorbent core 910. The EL line enables or facilitates controlled contraction of the absorbent core 910. The EL line defines a pivot line 912 during folding of the absorbent core 910. For example, when the absorbent core 910 is positioned between the user's thighs, the user's thighs can exert a force on the absorbent core 910 having a force component directed parallel to the lateral centerline of the absorbent core 910, a force component directed in the z-direction, or a combination thereof. Such forces can result in folding and contraction around and along the EL line, particularly in the central crotch region 915 of the absorbent core 910. Such contraction and / or folding of the absorbent core 910 can be limited to or at least concentrated in the central crotch region.

[0121] The particular shape that core 910 is prompted to assume when worn can vary depending, for example, on the number of EL lines, the spacing between the EL lines, the lateral width of the EL lines, the spacing and width between the SAP-free and SAP-containing lanes, and the number of EL lines, SAP-free lanes, and SAP-containing lanes. The absorbent core 910 is not limited to folding into the shape shown in Figure 9A.

[0122] In use, the EL lines of the core 910 enable the core 910 to dynamically respond to dynamically changing forces applied thereto when worn by a user. For example, as a user walks, the forces applied to the core 910 change with the movement of the user's legs. The EL lines enable the core 910 to dynamically at least partially fold and at least partially unfold in response to the changing forces applied thereto. As shown in FIG. 9B , when folded or bent, the core 910 can define a trough 917 in which the lateral sections 913 are angled upward relative to the central section 915. The trough 917 can function to prevent leakage from the lateral side edges of the core 910. That is, for fluid to flow past the lateral side edges of the core 910, the fluid must flow upward against gravity along the “wings” formed by the lateral sections 913.

[0123] Slit or opening Figure 10 is an exploded perspective view of a multilayer absorbent core composite MLC1010 including a slitted nonwoven layer SNW aligned with and positioned downstream adjacent to an absorbent material layer AM1 characterized by cross-directional absorbent-free lanes FL. The initial fluid infiltration first reaches the top nonwoven layer AT, which distributes the fluid flow to the top absorbent material layer AM1. The absorbent-free lanes FL of AM1 facilitate distribution of the fluid infiltration to the lateral side edges of the MLC1010 by directing the fluid laterally within the MLC1010. The slitted nonwoven layer SNW includes a plurality of slits 1011. As shown in Figure 10, the slits 1011 are aligned and extend in the machine direction perpendicular to the extent of the absorbent-free lanes FL, which are aligned and extend in the cross direction. However, the absorbent cores disclosed herein are not limited to this configuration and can include slits that are not aligned with one another, slits that extend in the cross direction, slits that extend perpendicular to both the cross direction and the machine direction, or slits that extend in parallel alignment with adjacent absorbent material-free lanes.

[0124] Slits 1011 positioned below the SAP in the AM1 layer facilitate the transport of fluid from AM1 through the SNW and to another SAP-containing layer AM2 positioned below the SNW. As with the other composites described above, the bottom SAP-containing layer AM2 provides additional storage for any remaining fluid not absorbed by the top SAP layer AM1.

[0125] Slitted nonwoven layers, such as SNW, can include any nonwoven, including NW, BNW, and BBNW, with one or more slits extending partially or completely therethrough. Slitted nonwovens can form any topsheet, backsheet, and / or intermediate sheet of the absorbent core composites disclosed herein. The slits can extend (partially or completely) only through the nonwoven layer without extending through other adjacent layers or absorbent materials (e.g., SAP particles), which could cause wear on the slit blade that forms them. In some embodiments, the slits are concentrated or positioned only in areas of the nonwoven layer aligned with the crotch region where fluid flow is expected to be greatest. Because embossing across the slits can reduce the size of the slits, the slits can be arranged and positioned away from the embossing points or lines on the absorbent core composite.

[0126] Interaction with slit-SAP In some aspects, when the slitted nonwoven layer is positioned above or below the absorbent material layer, at least some of the absorbent material (e.g., SAP) is deposited or otherwise positioned at least partially within the slits. In some embodiments, a vacuum force is used to apply and / or position the absorbent material onto the nonwoven layer, which forces at least some of the absorbent material at least partially into the slits. In other embodiments, the slits are free of absorbent material.

[0127] In some aspects, when the slit is open and extends completely through the nonwoven layer from the body side to the opposite side, at least some of the absorbent material is transported through the slit from a location above the slit (e.g., in the upper absorbent layer) to a location below the slit (e.g., in the lower absorbent layer). Thus, the slit can allow for the transport of absorbent material from one absorbent layer, such as AM1, to another absorbent layer, such as AM2. In other aspects, the slit is too narrow to allow the absorbent material to pass through.

[0128] Alignment to slit-SAP lane and SAP-free lane In some aspects, for example, to avoid SAP deposition in the slits, the slits on the slitted nonwoven are aligned with SAP-free lanes in the absorbent material layer. Aligning the slits with SAP-free lanes or SAP-free areas can improve fluid flow to the lower areas of the core. In other embodiments, for example, to promote SAP deposition in the slits, the slits are aligned with SAP-containing lanes. The slits can be aligned with both SAP-containing and SAP-free lanes. However, in some aspects, SAP can be placed across or within the slits to reduce fluid flow into the lower layer.

[0129] System and process for creating SAP-free zones 11 and 12 are schematic perspective views of a system and process for adding an absorbent core material layer featuring an absorbent material-free zone according to the present disclosure. Referring to FIG. 11, system 1100 includes a SAP distributor SD, which may be a hopper with a selectively positioned outlet (not visible in this view) that allows for dispensing SAP onto a high-loft nonwoven (BNW1) in SAP lanes sandwiching a non-existent lane FL. System 1100 is configured to form machine-direction SAP lanes. Machine rollers 1111 position an additional high-loft nonwoven (BNW2) on top of the deposited SAP, thereby sandwiching the SAP between the two high-loft nonwovens BNW1 and BNW2.

[0130] Referring to FIG. 12 , system 1200 includes a SAP distributor SD that deposits SAP into SAP sections on a lofty nonwoven fabric BNW1 having SAP-free lanes FL in both the cross and machine directions so that a grid pattern is formed. The SD of FIG. 12 can be adapted to have a selectively openable and closeable valve to open and close an outlet, allowing SAP to be distributed into the SAP sections on the lofty nonwoven fabric BNW1 having SAP-free lanes FL in both the cross and machine directions. The SD of FIG. 12 can apply an intermittent SAP stream. This can be achieved by having openings on the SD that open and close. Alternatively, it can be achieved using a gravure roll or a vibrating channel (with intermittent vibration pulses).

[0131] In some aspects, SAP-free lanes are advantageous in areas receiving the highest volumetric flow rates (i.e., near the target zones and surfaces) because they provide void volume that allows more free flow in the z, x, and y directions toward the rest of the diaper. The SAPs can absorb at a normal rate, but excess liquid can bypass the SAPs and reach other areas of the diaper through the SAP-free lanes, where it can be absorbed and contained by other SAPs. Thus, a preferred embodiment that places SAP-free zones will have SAP-free lanes in the first or first few absorbent material layers, optionally without any SAP-free lanes in the bottom SAP layer.

[0132] In some aspects, the SAP properties are the same for all SAP layers or lanes within a composite. In other embodiments, the properties of the SAP used in each layer or lane are controlled and varied to enable more rapid fluid acquisition, distribution, and more efficient utilization of the absorbent core. The SAP layer closest to fluid release will have high fluid permeability to maximize inward fluid flow (z-flow) and lateral distribution (x- and y-flow). SAP-free lanes are advantageous in providing this same functionality in upper layers. SAPs with slower absorption rates can be advantageously utilized in upper layers, as they can allow for more fluid bypass during periods of high fluid infiltration. SAP layers can be progressively faster toward the bottom of the core. In some aspects, it is advantageous to match the SAP particle size with the BNW density for optimal particle immobilization within the BNW. The NW bulking process may be controlled by manipulating the mechanical brushing process conditions (discussed in more detail below) to achieve the desired density for optimal immobilization of the SAP particle size range.

[0133] Online fiber scattering / loose fiber layer In some embodiments, the multilayer absorbent core composites disclosed herein include at least one "loose" fiber layer. As used herein, "loose fibers" refers to a group of multiple individual fibers that are not bonded to one another, such as in a web (e.g., the fibers do not form a nonwoven or woven web). Thus, each individual fiber of the loose fibers is separable from and movable relative to other individual fibers of the loose fibers.

[0134] 13A-13C are schematic front views of multilayer absorbent core composites or constructs MLC1300a, MLC1300b, and MLC1300c, each including a loose fiber layer 1301a or 1301b. The fiber layers 1301a and 1301b provide rapid acquisition and distribution functions and are strategically positioned upstream of or adjacent to the SAP layers in a more intermediate position. In FIGS. 13A and 13B, the fiber layers 1301a and 1301b are positioned between two SAP layers 1310a and 1310b, respectively, to facilitate the passage of fluid intake not absorbed by the first SAP layer 1310a to additional SAP material in the second SAP layer 1310b. Unlike other BNW layers, the fibers of the fiber layers 1301a and 1301b (also referred to as fiber net layers) are not bonded, facilitating greater fluid flow between the two adjacent SAP layers 1310a and 1310b. Without being bound by theory, it is believed that the non-bonded fibers allow for greater control over the application of fiber layers 1301 a and 1301 b. The amount and composition of fiber layers 1301 a and 1301 b can be varied in the x-, y-, and / or z-directions. The non-bonded fibers of fiber layers 1301 a and 1301 b are unconstrained and can be manipulated to align or pack as needed to achieve a desired effect.

[0135] Referring to FIG. 13A, an exemplary absorbent composite MLC 1300a is depicted that includes a loose fiber layer 1301a, which is a single layer of scattered loose fibers. The loose fiber layer 1301a is shown positioned between two absorbent material layers 1310a and 1310b. Those skilled in the art will appreciate that such loose fibers can be positioned between two nonwoven layers or between a nonwoven and an absorbent material layer. These fibers can be scattered directly on the SAP and / or the nonwoven. The scattered loose fibers of the loose fiber layer 1301a provide a layer of open void space within the MLC 1300a that facilitates faster fluid acquisition through the MLC 1300a. In some aspects, SAP is added onto and mixed into the scattered loose fibers of the loose fiber layer 1301a. The MLC 1300a further includes a bodyside nonwoven layer 1320a positioned above the first SAP layer 1310a, a nonwoven layer 1320b positioned below the second SAP layer 1310b, and a third nonwoven layer 1310c positioned below the second SAP layer 1310b. Each nonwoven layer of the composite containing scattered free fibers can be any nonwoven disclosed herein, including a BNW layer, a BBNW layer, and a slit nonwoven layer. Each absorbent material layer of the composite containing scattered free fibers can be any absorbent material layer disclosed herein, including those having SAP-containing lanes and SAP-free lanes.

[0136] The fibers of the loose fiber layer 1301a can be arranged in a scattered random configuration, as shown in FIG. 13A. In other embodiments, the fibers of the loose fiber layer are arranged in a regular configuration. For example, referring to FIG. 13B, the fibers of the loose fiber layer 1301b are aligned in the z-direction. The fibers can be aligned in other regular configurations or directions, such as the x- or y-directions. The fibers of the loose fiber layer 1301b can be aligned using electrostatic forces (flocking). For example, the fibers can be of a composition that has the ability to retain an electric charge (e.g., polyester fibers). In such embodiments, an electric field applied to the fibers aligns them in one direction (machine direction, cross direction, or any desired direction). Because the fibers are not bonded or attached to each other, they are separable from each other and can enter into an aligned state in response to the electric field. Once the desired alignment is achieved, the application of the electric charge can be discontinued.

[0137] Some fibers suitable for use as scattering fibers include, but are not limited to, cellulosic fibers (e.g., wood pulp fibers, viscose fibers, rayon fibers), synthetic fibers (e.g., polypropylene fibers, polyethylene fibers, polyester fibers), or combinations thereof. In certain embodiments, the fibers comprise multicomponent (e.g., bicomponent) fibers. As used herein, a "bicomponent" fiber is a fiber made of two materials having different chemical and / or physical properties. For example, a bicomponent fiber can be a fiber made of two different polymers. A bicomponent fiber can have a core / shell morphology.

[0138] In some aspects, all of the fibers in the loose fiber layer are identical or substantially identical in shape, size, composition, chemical properties, mechanical properties, and any other physical properties. In other embodiments, fibers having a mixture of shapes, sizes, compositions, chemical properties, mechanical properties, and / or any other physical properties are used in the loose fiber layer.

[0139] The properties of the free fiber layer can be varied by varying any number of parameters, including, but not limited to, the number and / or mass of fibers in the free fiber layer, the fiber composition, the fiber mix (e.g., a mix of more than one fiber type), the fiber density, the fiber thickness, the fiber length and / or width, the chemical functionality of the fibers (e.g., graft fibers), and the positioning, placement, and orientation of the fibers. The fibers can be positioned in SAP-containing lanes, SAP-free lanes, in slits, on or in the BBNW section of the nonwoven, on or in the non-bulked section of the BNW, or a combination thereof.

[0140] In some aspects, a needle roll diffuser is used to scatter the fibers onto the layer of absorbent core composite, while in other embodiments, a flocking process is used in which an electric field is applied to the web and scattering fibers as the fibers are deposited.

[0141] Figure 13C shows an alternative arrangement of absorbent composite layers combining BNW, sectional BBNW, SAP-free lanes, SAP-containing lanes, loose fibers, and a slitted nonwoven. The MLC 1300c includes a top, bodyside slitted nonwoven layer 1321, beneath which a loose fiber layer 1301a is positioned, and which is deposited on top of a top absorbent material layer 1311. The absorbent material layer 1311 includes SAP-containing lanes 1311a and SAP-free lanes 1311b. Below the absorbent material layer 1311 is positioned a sectionally lofted high-loft nonwoven layer 1323, which includes a BBNW section 1323a aligned with the SAP-containing lane 1311a and a non-lofted section 1323b aligned with the SAP-free lane 1311b. Positioned below the sectionally bulked high-loft nonwoven layer 1323 is an SAP layer 1312 without any SAP-free lanes, and below that is a BNW layer 1325 without any lofted sections. During wetting, the slitted nonwoven 1321 promotes fluid distribution toward the loose fiber layer 1301a, and the fibers of the loose fiber layer 1301a promote fluid distribution to both the SAP-free lane 1311b and the SAP-containing lane 1311a. The SAP in the SAP-containing lane 1311a can be supported on or in the bulked section 1323a, which can promote intracapillary migration to the SAP layer 1312. The fibers in the non-bulked section 1323b can promote intracapillary migration from the SAP-free lane 1311b to the SAP layer 1312. The SAPs of SAP layer 1312 may be supported on fibers of BNW layer 1325 that may facilitate intracapillary migration from one portion of the SAP layer to another.

[0142] In use, the fibers of the free fiber layer disclosed herein can promote capillary migration, fluid distribution, and enhance compressibility as well as comfort to the user. The fibers of the free fiber layer can direct fluid flow within the core composite, particularly when the fibers are aligned, such as by an electric field.

[0143] System and process for depositing a loose fiber layer - Patents.com FIG. 14A illustrates a system 1400 for forming an absorbent core composite including a loose fiber layer. FIG. 14A is identical to FIG. 5 except that the "SAP application unit 5" has been replaced with a fiber applicator 1401. The fiber applicator 1401 is a device that scatters or otherwise deposits fibers onto a laminate of nonwovens and / or absorbent materials passing thereunder to form a loose fiber layer on the laminate. While the fiber applicator is shown in one position within the manufacturing process, the fiber applicator can be positioned at different locations within the manufacturing process to provide loose fiber layers at different locations within the absorbent core composite. Furthermore, in some aspects, absorbent core composites having multiple loose fiber layers are formed.

[0144] 14B shows a detailed view of an exemplary fiber applicator 1401. The fiber applicator 1401 can include a hopper 1403 that confines loose fibers 1405. A distribution roller 1407 can be actuated (e.g., rotated) in conjunction with roller 1409 to distribute scattered portions of the loose fibers 1405 from the hopper 1403 onto the nonwoven fabric NW passing thereunder to form a loose fiber layer 1301 on the nonwoven fabric NW. The fiber applicator 1401 further includes an agitator 1411 for agitating the fibers 1405 and a distribution adjuster 1413 for adjusting the distribution of the fibers 1405.

[0145] In some embodiments, the loose fibers remain free and unbonded within the absorbent core after being deposited (e.g., scattered). In other embodiments, the loose fibers do not remain free and unbonded within the absorbent core. For example, in some such embodiments, an adhesive or other binder is applied to the top surface of the loose fibers after they are deposited on the nonwoven. In other such embodiments, the adhesive or other binder is applied to the surface of the nonwoven before the loose fibers are deposited thereon. In some embodiments, the adhesive or other binder is applied before or after the application of the SAP to the top surface of the loose fibers. When the adhesive or other binder is applied after the application of the SAP, the adhesive or binder can secure the SAP by bonding it to the loose fibers, the underlying nonwoven, or a combination thereof, in addition to securing the loose fibers. The adhesive or binder can be or include a hot melt adhesive (HMA), which can be applied by spray application or by adding particles that are subsequently activated later downstream in the process. Bonding can be achieved by using a step of including at least some thermoplastic fibers in the mixture of loose fibers that is applied onto the nonwoven. Such thermoplastic fibers can later be heated to heat-melt the points where the loose fibers intersect with one another so that the loose fibers are bonded together to form a web. Thus, the loose fibers can be added in a free state, but later bonded together in a web or web-like structure, thereby forming a nonwoven web in situ. The web thus formed, or the loose fibers when unbonded, can contain SAP particles in some embodiments. In other embodiments, the web thus formed, or the loose fibers when unbonded, do not contain SAP particles and / or other absorbent materials.

[0146] Bulking - Incision of bulky nonwoven fabric In some aspects, at least one nonwoven layer of the absorbent core composite is "bulked" such that the nonwoven is "bulked."

[0147] Bulking - Pre- and Post-bulking Referring to Figures 15A, 15B, and 15C, a nonwoven fabric is shown before and after bulking, respectively. Before bulking, the nonwoven fabric has a first width, depth, and height. After bulking, the nonwoven fabric has at least one width, depth, and height that is greater than the previous width, depth, and height. Thus, the constituent fibers of the nonwoven fabric occupy a greater volume after bulking. Thus, the nonwoven fabric has a first bulk density before bulking and a second bulk density after bulking that is lower than the first bulk density. As used herein, "bulk density" refers to the total mass of the nonwoven fabric divided by the total volume occupied by the nonwoven fabric. As used herein, "bulk density" can be determined by any number of methods and techniques known to those skilled in the art, including those disclosed in the examples discussed with reference to Figures 22A and 22B.

[0148] Additionally, lofting a nonwoven increases the distance between adjacent fibers within the nonwoven, thus increasing the total void volume of the nonwoven. As used herein, "void volume" refers to the volume not occupied by solids (i.e., fibers) but occupied by voids (i.e., the spaces between fibers). As used herein, "void volume" can be determined by any number of methods and techniques known to those skilled in the art, including those disclosed in the examples discussed with reference to Figures 22A and 22B.

[0149] For illustrative purposes, referring to both Figures 15A and 15B, the increase in volume within a single section of a nonwoven fabric's total void volume is shown. In Figure 15A, before bulking, the single section of nonwoven fabric has a first void volume. After bulking, the same single section of nonwoven fabric has a second void volume that is greater than the first void volume. Those skilled in the art will understand that the same increase in volume of void space in a nonwoven fabric due to bulking will occur in different sections of the nonwoven fabric. Thus, the total void volume of the nonwoven fabric increases due to bulking.

[0150] In some aspects, the entire surface of the nonwoven fabric is bulked. In other embodiments, at least one section of the nonwoven fabric is bulked and at least one section of the nonwoven fabric is not bulked. In some aspects, only the section of the nonwoven fabric where SAP or other absorbent material will be deposited is bulked. For example, any of the bulked nonwoven fabrics described herein can include any of the SAP-free lanes described elsewhere herein. The bulked sections of the bulked nonwoven fabric can be aligned with the SAP-containing lanes, zones, or sections such that SAP (or other absorbent material) is deposited only or substantially only on the bulked sections of the nonwoven fabric. In such embodiments, the non-bulked sections of the nonwoven fabric (i.e., the sections of the nonwoven fabric that were not bulked) are aligned with the SAP-free lanes. Thus, lofted sections can be added to the nonwoven fabric corresponding to the pattern of SAP-free lanes, such that the non-lofted sections are aligned with the SAP-free lanes. By lofting only selected sections of the nonwoven fabric and not other selected sections or zones of the nonwoven fabric, a high degree of control over the capillarity of the nonwoven fabric and associated absorbent material layers is possible. In some embodiments, absorbent material is added only to the lofted sections of the BBNW per section.

[0151] In some embodiments, absorbent material is added only to the non-lofted sections of the BBNW per section. In some embodiments, absorbent material is added to both the lofted and non-lofted sections of the BBNW per section. Figures 16A and 16B show cross-sectional views of nonwovens 1600a and 1600b, respectively. Nonwoven 1600a includes four non-lofted lanes 1606 and three lofted lanes 1608. Nonwoven 1600b includes two non-lofted lanes 1606 along its side edges and a single lofted section 1608 between the two non-lofted lanes 1606.

[0152] 16C , in some aspects, a bulked high loft nonwoven layer 1600c includes longitudinal SAP-containing lanes 1650 formed adjacent to lofted lanes 1655. The lofted nonwoven 1660 may be selectively bulked in the lofted sections 1665 and selectively unbulked in the non-bulked sections 1670. The lofted sections 1665 have a greater height in the y-direction compared to the non-bulked sections 1670, forming SAP-containing lanes 1650 within which SAP 1666 can be deposited and trapped.

[0153] 16D , in some aspects, the bulked high loft nonwoven layer 1600c includes longitudinal SAP-free lanes 1650 formed adjacent to the lofted lanes 1655. The lofted nonwoven 1660 may be selectively bulked in the lofted sections 1665 and selectively not bulked in the non-lofted sections 1670. The lofted sections 1665 will have a greater height in the y-direction compared to the non-lofted sections 1670. SAP may be deposited in the lofted lanes 1655 and not deposited in the non-lofted lanes 1650, such that the non-lofted lanes 1650 form SAP-free lanes. The SAP may be trapped (e.g., entangled) within the fibers of the lofted sections 1655.

[0154] In use, the presence of fibers in the SAP-free lane can help control fluid flow compared to a completely empty channel. An empty channel has a higher void volume for fluid, but is essentially uncontrolled and unable to move intrapellations along the channel. If the fiber network in the SAP-free lane has proper capillarity, liquid can move intrapellations along the channel and supply the SAP up to a height that the capillary structure of the NW can support. When the absorbent product is worn as a garment and is in a "U" shape, the higher region compared to the wetting point can have a capillary structure that supports intrapellations up to the relative height of this region for maximum utilization of the absorbent core. This can be achieved by selective bulking around the wetting point and, if necessary, by selective densification at the edges of the absorbent core.

[0155] In some embodiments, the SAP is in a dry state (not in the form of a wet slurry) when added to the BBNW.

[0156] In one embodiment, a preferred absorbent core composite incorporating a BBNW includes a top layer of an air-permeable nonwoven (ATNW), a middle sectionally lofted BBNW with two lofted NW lanes containing SAP, and a bottom SAP layer. The alternating SAP and ATNW layers facilitate interlayer fluid distribution. The ATNW layer provides bulk for passageways for liquid to spread within the core.

[0157] Bulking - Absorbent core composite with bulking nonwoven layer FIG. 17 shows a preferred embodiment of an absorbent core composite MLC 1700 that includes multiple absorbent material layers 1702a and 1702b and multiple nonwoven layers 1704a, 1704b, and 1704c.

[0158] In the embodiment shown in FIG. 17 , the base or substrate nonwoven layer 1704c and the intermediate nonwoven layer 1704b are shown as having lofted sections 1706, with the remaining sections being unlofted. The top or cover nonwoven layer 1704a does not include any lofted sections. However, one skilled in the art will understand that an absorbent core composite according to the present disclosure can include lofted sections 1706 or lofted layers in an arrangement different from that shown in FIG. 17 . In some aspects, each nonwoven layer of the absorbent core composite includes at least one lofted section or is a full lofted layer. The base nonwoven layer, one or more intermediate nonwoven layers, the top nonwoven layer, or any combination thereof can include at least one lofted section or can be a full lofted layer. Similarly, while MLC1700 is a multi-layer composite, the use of bulking sections or nonwoven layers is not limited to use in multi-layer composites and can be implemented in embodiments that include only one nonwoven layer and / or only one absorbent material layer.

[0159] The absorbent material layer 1702b is formed by depositing a plurality of SAP particles onto the lofted section 1706 of the base nonwoven layer 1704c. In some aspects, the SAP particles deposited on the base nonwoven layer 1704c all have the same set of properties. In other embodiments, at least some of the SAP particles deposited on the base nonwoven layer 1704c have at least one property that differs from at least some others of the SAP particles deposited on the base nonwoven layer 1704c. Properties of the SAP particles that may be the same or different include, but are not limited to, particle size, material composition, saturation and swelling characteristics, processing (e.g., whether and to what extent the SAP has been cross-linked), and other properties. For example, a first plurality of SAP particles can be positioned on the base nonwoven layer 1704c in a primary target area (e.g., an expected wetout area) of the absorbent core composite 1700 having a first set of properties, and at least one other plurality of SAP particles can be positioned on the base nonwoven layer 1704c in other areas of the absorbent core composite 1700. The locations of the SAP particles with varying properties within the absorbent core composite 1700 can be positioned to optimize fluid flow and distribution within the absorbent core composite 1700.

[0160] The intermediate nonwoven layer 1704b is positioned above the absorbent material layer 1702b such that the absorbent material layer 1702b is sandwiched between the intermediate nonwoven layer 1704b and the base nonwoven layer 1704c. In some aspects, the intermediate nonwoven layer 1704b is bonded to the base nonwoven layer 1704c by bond sites, bond points, bond lines, or the like, as disclosed in U.S. Patent Nos. 5,929,999 and 5,929,999.

[0161] The absorbent material layer 1702a is formed by depositing a plurality of SAP particles onto a lofted section 1706 of an intermediate nonwoven layer 1704b. In the same manner as described above with respect to the absorbent material layer 1702b, the SAP particles deposited onto the intermediate nonwoven layer 1704b (or at least one lofted section 1706 thereof) can all have the same set of properties, or the SAP particles can have properties that vary from one lofted section 1706 to another or within a single lofted section 1706. For example, a first plurality of SAP particles 1703b can be positioned on the intermediate nonwoven layer 1704b in a bulking section 1706b having a first set of properties in a primary target area (e.g., an expected wet-out area) of the absorbent core composite 1700, and two additional plurality of SAP particles 1703a and 1703c can be positioned on the intermediate nonwoven layer 1704b in bulking sections 1706a and 1706c at or near the side edges of the intermediate nonwoven layer 1704b.

[0162] The top nonwoven layer 1704a is positioned above the absorbent material layer 1702a such that the absorbent material layer 1702a is sandwiched between the middle nonwoven layer 1704b and the top nonwoven layer 1704a. In some aspects, the middle nonwoven layer 1704b is bonded to the top nonwoven layer 1704a by bond sites, bond points, bond lines, or the like, as disclosed in U.S. Patent Nos. 9,757,284 and 9,789,014.

[0163] 17, only the section of the nonwoven layer on which the SAP is deposited is bulked, while the remainder of the nonwoven layer remains bulked. However, in other aspects, portions of the nonwoven layer on which the SAP is not deposited can be bulked.

[0164] In some aspects, the top nonwoven layer 1704a and the middle nonwoven layer 1704b are breathable nonwovens, and the base nonwoven layer 1704c is an SMS nonwoven. In one embodiment, the lofted nonwoven layers (in this embodiment, the middle nonwoven layer 1704b and the base nonwoven layer 1704c) function as acquisition and distribution layers within the absorbent core composite.

[0165] Core composition including bulking sections or layers 18A-18F show various absorbent core constructions according to certain aspects of the present disclosure.

[0166] 18A includes a high-loft nonwoven topsheet layer 1801, which includes a lofted section 1801a and a non-lofted section 1801b. An absorbent material layer 1802 is positioned below the topsheet layer 1801 and includes an SAP-containing lane 1802a and an SAP-free lane 1802b. As shown, the SAP-free lane 1802b is positioned below the lofted section 1801a, and the SAP-containing lane 1802a is positioned below the non-lofted section 1801b, allowing fluid transport from the lofted section 1801a into the SAP-free lane 1802b and, optionally, absorption into the SAP in the adjacent SAP-containing lane 1802a. Thus, the lofting section 1801a and the SAP-free lane 1802b can synergistically provide intracapillary migration paths or channels for fluid in the absorbent core composite 1800a to migrate to the SAP contained within the absorbent core composite 1800a. In some aspects, this arrangement is reversed so that the SAP-free lane 1802b is positioned below the non-lofting section 1801b and the SAP-containing lane 1802a is positioned below the lofting section 1801a. A slitted nonwoven layer 1803 is positioned below the absorbent material layer 1802. As shown, the slit 1803a is aligned with the SAP-free lane 1802b, providing an intracapillary migration path for fluid in the SAP-free lane 1802b to flow to the second absorbent material layer 1804. This arrangement can be reversed so that the slit is aligned with the SAP-containing lane 1802a. This can allow fluid to flow from the SAP-containing lanes 1802a to the second absorbent material layer 1804, such as when the SAP in the absorbent material layer 1802 becomes saturated. The second absorbent material layer 1804 is positioned below the slitted nonwoven layer 1803 and includes SAP-free lanes 1804a at its side edges and a SAP-containing central lane 1804b between the SAP-free lanes 1804a. The upper absorbent material layer 1802 can be operated to direct fluid flow through the SAP-free and SAP-containing lanes, while the second absorbent material layer 1804 can act as a high-loft, fluid-absorbing zone. The backsheet layer 1805 is shown as a high-loft nonwoven.In some aspects, the topsheet layer 1801 is the bodyside layer.

[0167] 18B shows an absorbent core composite 1800b that includes a slitted nonwoven topsheet layer 1801. Positioned below the topsheet layer 1801 is an absorbent material layer 1802, which includes an SAP-containing lane 1802a and an SAP-free lane 1802b. Positioned below the absorbent material layer 1802 is a sectionally bulked nonwoven layer 1803, which includes a bulked section 1803a and a non-bulked section 1803b. As shown, the SAP-free lane 1802b is positioned above the bulked section 1803a, and the SAP-containing lane 1802a is positioned above the non-bulked section 1803b, allowing fluid transport from the SAP-free lane 1802b into the bulked section 1803a and, optionally, absorption into the SAP in the adjacent SAP-containing lane 1804b. In some aspects, this arrangement is reversed so that the SAP-free lane 1802b is positioned above the non-lofted section 1803b and the SAP-containing lane 1802a is positioned above the lofted section 1803a. A second absorbent material layer 1804 is positioned below layer 1803 and includes SAP-free lanes 1804a at its side edges and SAP-containing central lanes 1804b between the SAP-free lanes 1804a. The backsheet layer 1805 is shown as a sectionally lofted high-loft nonwoven that includes lofted sections 1805 aligned with the SAP-free lanes 1804a and optionally includes non-lofted sections (not shown) aligned with the SAP-containing lanes 1804b. In some aspects, the topsheet layer 1801 is the bodyside layer.

[0168] The absorbent core composite 1800c shown in Figure 18C includes a high-loft nonwoven topsheet layer 1801. Positioned below the topsheet layer 1801 is an absorbent material layer 1802, which includes SAP-containing lanes 1802a and SAP-free lanes 1802b. The absorbent material layer 1802 can be the same or substantially similar to that shown in Figure 16C, with SAP supported within non-lofted sections of the high-loft nonwoven and lofted sections of the high-loft nonwoven positioned between the non-lofted sections. Positioned below the absorbent material layer 1802 is a slitted nonwoven layer 1803. Positioned below the slitted nonwoven layer 1803 is a second absorbent material layer 1804, which includes SAP and / or another absorbent material. Positioned below the second absorbent material layer 1804 is a lofted high loft nonwoven layer 1805. The lofted high loft nonwoven layer 1805 is not lofted in sections, but is completely or substantially completely lofted across at least one surface thereof. In some aspects, the topsheet layer 1801 is a bodyside layer.

[0169] Figure 18D shows an alternative absorbent core construction 1800d. The top sheet layer, which may be NW, BNW, and / or BBNW, is the bodyside layer and receives the exudates, which pass through the top sheet layer into the first absorbent material layer, shown in this figure as including both SAP-free and SAP-containing lanes. At least some of the liquid from the top sheet layer flows into the SAP-containing lanes and is absorbed into the SAP. Furthermore, at least some of the liquid from the top sheet layer flows into the SAP-free lanes, where it can flow laterally into the SAP in the SAP-containing lanes or downward into the middle nonwoven layer. In this figure, the middle nonwoven layer is shown as a sectionally lofted high-loft nonwoven, including both lofted and lofted high-loft nonwoven sections. The BBNW section is aligned with the SAP-containing lane of the upper absorbent material layer. The fibers of the BBNW form a capillary migration path for liquid in the SAP-containing lane to flow downward into the SAP-containing lane of a second absorbent material layer positioned below the middle nonwoven layer. For example, if the SAP in the upper SAP-containing lane becomes saturated, liquid can flow through the BBNW fibers into the SAP-containing lane. The second absorbent material layer is supported on the high loft nonwoven layer.

[0170] Figure 18E shows an alternative absorbent core construction 1800e. The top sheet layer, a BNW with slits at least partially therethrough, is the bodyside layer and receives the exudates through the top sheet layer and into the first absorbent material layer, shown in this figure as including both SAP-free and SAP-containing lanes. The slits in the top sheet layer are aligned with the SAP-free lanes to direct fluid flow therein. At least some of the liquid from the top sheet layer flows directly into the SAP-containing lanes and is absorbed into the SAP. Furthermore, at least some of the liquid from the top sheet layer flows through the slits into the SAP-free lanes, where it can flow laterally into the SAP of the SAP-containing lanes or downward into the intermediate nonwoven layer. In this figure, the intermediate nonwoven layer is shown as a sectionally lofted high-loft nonwoven that includes both lofted and lofted high-loft nonwoven sections. The BBNW section aligns with both the SAP-containing and SAP-free lanes of the upper absorbent material layer. The fibers of the BBNW form intracapillary migration paths for liquid in the SAP-free and SAP-containing lanes to flow downward into the second absorbent material layer positioned below the intermediate nonwoven fabric layer. The second absorbent material layer includes a first SAP-containing lane and a second SAP-containing lane. The second SAP-containing lane can contain SAP that is different in at least some respects from the first SAP-containing lane. For example, the second SAP-containing lane can contain SAP of a different type and / or material composition, a different size, or with different absorption characteristics. In some aspects, the second SAP-containing lane differs from the first SAP-containing lane in that one of the lanes contains SAP mixed with non-SAP and optionally contains non-absorbent particles such as spacers, inert particles, water-soluble particles, volatile particles, ion-exchange particles, or any combination thereof. Additive particles, such as ion-exchange particles, can be deposited within the target area. It is believed that the ionic strength of urine increases due to SAP absorbing water from the urine as it passes through a bed of SAP material.The introduction of ion exchange particles along the fluid path, including mixing such particles with the SAP, reduces the ionic strength of the fluid absorbed therein, thereby maintaining the absorption capacity of the SAP. A second absorbent material layer is supported on the high loft nonwoven layer.

[0171] FIG. 18F shows an alternative absorbent core construction 1800f. The top sheet layer, a BBNW, is fully lofted on at least one side. The fibers of the BBNW layer receive the exudate, which passes through the top sheet layer into the first absorbent material layer, shown in this figure as including both SAP-free and SAP-containing lanes. At least some of the liquid from the top sheet layer flows directly into the SAP-containing lane and is absorbed into the SAP. Furthermore, at least some of the liquid from the top sheet layer flows through slits into the SAP-free lane, where it can flow laterally into the SAP of the SAP-containing lane or downward into the middle nonwoven layer. In this figure, the middle nonwoven layer is shown as a section-lofted high-loft nonwoven, including both high-loft and lofted high-loft nonwoven sections. Optionally, one or more sections of the middle BBNW layer can have slits extending therethrough. The high loft section of the intermediate BBNW is aligned with a portion of the SAP-containing lane and with both the SAP-free lane of the upper absorbent layer. The fibers of the BBNW form intracapillary migration paths for liquid in the SAP-free and SAP-containing lanes to flow downward into a second absorbent layer positioned below the intermediate nonwoven layer. The second absorbent layer is supported on the high loft nonwoven layer.

[0172] 19A and 19B are cross-sectional views of an absorbent core composite including a bulked high loft nonwoven.

[0173] 19A shows a cross-sectional view of an absorbent core composite 1680d. The absorbent core composite 1680d includes a topsheet 1681, which can be a permeable layer, and a backsheet 1682, which can be an impermeable layer. Sandwiched between the topsheet 1681 and the backsheet 1682 are multiple nonwoven layers and absorbent material layers. Beneath the topsheet 1681, the absorbent core composite 1680d includes a slitted nonwoven 1683 having a slit 1684 therethrough. Positioned beneath the slitted nonwoven 1683 is a lofted high-loft nonwoven layer 1685. Bulked high loft nonwoven layer 1685 can be the same as or substantially similar to layer 1600c shown in Figure 16C, and includes an absorbent layer disposed in an absorbent material lane 1686 (i.e., an SAP lane) positioned in a non-lofted section 1688 adjacent to an SAP-free lane 1687 of a lofted nonwoven 1687. Positioned below the lofted high loft nonwoven layer 1685 is a lofted high loft nonwoven layer 1685b having a different pattern of lofted and non-lofted sections than the lofted high loft nonwoven layer 1685. Bulked high loft nonwoven layer 1685a includes unlofted side edges 1688b and a lofted central region 1687b. Within the bulked high loft nonwoven layer 1685a, the bulked section 1687b contains SAP 1686b, and the non-bulked section 1688b does not contain SAP. The bulked high loft nonwoven layer 1685a is positioned above the backsheet 1682. In some aspects, each layer of the composite 1680d is bonded to an adjacent layer. In some embodiments, only the nonwoven layers are bonded to each other, and the absorbent material is entangled with but not bonded to the fibers of the nonwoven.

[0174] 19B shows a cross-sectional view of an absorbent core composite 1690. The absorbent core composite 1690 includes a topsheet 1691 and a backsheet 1692. Multiple nonwoven layers and absorbent material layers are sandwiched between the topsheet 1691 and the backsheet 1692. Beneath the topsheet 1691, the absorbent core composite 1690 includes a nonwoven 1693. Positioned below the nonwoven 1693 is a bulked, high-loft nonwoven layer 1694. The bulked, high-loft nonwoven layer 1694 may include an arrangement of slits therethrough and an arrangement of SAP lanes 1695 and SAP-free lanes 1698. Positioned below the bulked, high-loft nonwoven layer 1694 is an absorbent material layer 1696 including SAP lanes 1695b and SAP-free lanes 1698b. The absorbent material layer 1696 is positioned above the nonwoven layer 1697 .

[0175] In some aspects, depending on the fiber composition of the nonwoven being bulked, the application of heat after the bulking step can stabilize the low-density structure and immobilize the SAP. Most low-density nonwovens have bicomponent fibers in their fiber composition. Such bicomponent fibers are fibers with a low-melting component that acts as a binder. Therefore, reheating during brushing / SAP deposition and subsequent cooling can achieve a somewhat low percentage of rebonding that can stabilize the structure of the bulked nonwoven.

[0176] Creating discrete areas of controlled pore size or density within the nonwoven can be accomplished by densifying (embossing) the nonwoven, with the minimum density dictated by the starting material nonwoven.

[0177] The step of creating discrete regions of controlled pore size or density within a nonwoven can be accomplished by cutting the structure within the discrete regions. In such an embodiment, the minimum achievable density is not limited other than by the processing parameters. Combining the discrete bulking and embossing steps can provide a wider density range (low to high) that can be used for a variety of applications.

[0178] In use, capillary migration in the y-direction (machine direction) is desired. Bulking the NW near the target area creates a pore structure with a large void volume that can transport fluid in a controlled manner to provide fluid to the SAP in capillary contact with the fluid. Absorbent products typically have a "U" configuration where significant sections must resist gravity to transport fluid. Therefore, a structure that supports capillary migration flow is desirable. Within such sections, a fiber network structure with appropriately sized pores (i.e., web density) is desirable. This structure can be accomplished by constructing a pore gradient structure within the BNW, where larger pores in the target zone transition to smaller pores toward the end of the absorbent product. This pore size change can be achieved by bulking, densification (embossing), or a combination thereof to achieve the desired pore gradient from large pores to small pores along the length (y-direction) of the absorbent product.

[0179] Bulking - Mechanical Bulking System 20 illustrates a bulking system 2000. The bulking system 2000 can be used to at least partially bulk any of the nonwoven layers disclosed herein. The bulking system 2000 includes a nonwoven supply or distributor 2001, a nonwoven manipulator 2003, and a bulked nonwoven collector 2005. The nonwoven supply 2001 provides a densified, non-bulked nonwoven 2004 to the nonwoven manipulator 2003. For example, the nonwoven supply 2001 can include a spool 2002 that unwinds the nonwoven 2004 for input into the nonwoven manipulator 2003.

[0180] Within nonwoven manipulator 2003, nonwoven 2004 is manipulated to form lofted nonwoven 2018. Manipulation of nonwoven 2004 can include any of a variety of treatments or steps of nonwoven 2004 to achieve "bulking" of nonwoven 2004 such that the bulk density of nonwoven 2004 is reduced and the void volume is increased, thereby forming lofted nonwoven 2018. This manipulation can include, but is not limited to, mechanical manipulation of nonwoven 2004, thermal manipulation of nonwoven 2004, or a combination thereof. During manipulation, the nonwoven is de-pile, brushed, fluffed, heated, and / or otherwise manipulated to "open up" the fiber matrix of the nonwoven, thereby reducing the density of the nonwoven and increasing the void volume. In some aspects, both the bodyside and non-bodyside surfaces of the nonwoven are "bulked" by brushing both sides of the nonwoven and / or heating the nonwoven. In some embodiments, the side of the NW on which the SAP is deposited is bulked. In such embodiments, the non-brushed side of the NW will be denser and have a smaller void volume than the brushed side, thereby trapping the SAP and reducing or preventing filtering of the SAP through the NW layer.

[0181] When a thermal operation is used to bulk the nonwoven, heat can be applied to one or both sides. In some aspects, both sides of the nonwoven exhibit loft even when heat is applied to only one side of the nonwoven. In some aspects, only the side of the nonwoven on which the SAP is applied is bulked.

[0182] In the embodiment shown in FIG. 20 , the operation is a mechanical operation that includes brushing the surface of the nonwoven fabric with brushes 2010a and 2010b (e.g., rotating brushes) as the nonwoven fabric passes through nonwoven fabric manipulator 2003. The nonwoven fabric is threaded through nonwoven fabric manipulator 2003 so that its surface engages bristles 2012 of brushes 2010a and 2010b. For example, a series of mechanical rollers 2008, 2014, 2019, and 2020 can operatively engage the nonwoven fabric and roll to thread the nonwoven fabric through nonwoven fabric manipulator 2003. As the bristles 2012 engage the surface of the nonwoven fabric, they can brush and / or backfurl the fibers of the nonwoven fabric, pulling the fibers against one another and achieving loft in the nonwoven fabric. As the fibers are brushed, they are displaced relative to one another due to the brushing action, resulting in greater void space between the fibers. Thus, the sheet thickness of the nonwoven increases and the density of the nonwoven decreases. As arranged in FIG. 20, brushes 2010a and 2010b engage and manipulate both opposing sides of the nonwoven. However, in some aspects, only one side of the nonwoven is manipulated. Furthermore, while each side of the nonwoven is shown as being manipulated by a single brushing device, in some aspects, multiple brushes positioned in series engage and manipulate one or both sides of the nonwoven. In some aspects, multiple brushes are positioned in parallel, each brush positioned to engage and manipulate a selected section of the nonwoven.

[0183] Increased volume - brush shape Referring to Figure 20A, there is shown a brushing device 2010c that includes a central brushing area 2012 containing bristles attached to a mechanical roller or brush axle 2015, and two non-brushing areas 2013 on either side thereof. As a brush such as brush 2010c passes, the section of the nonwoven fabric that is aligned with and engages the central brushing area including 2012 will be bulked, while the portion of the nonwoven fabric aligned with the two non-brushing areas 2013 will remain in a non-bulked (densified) state.

[0184] Referring to Figure 20B, a brushing device 2010d is shown configured to form a nonwoven fabric having lanes of lofted and non-lofted sections. The brushing device 2010d includes a brushing region 2012 including bristles 2012 attached to a mechanical roller or brush axle 2015, and an adjacent non-brushed region 2013. As a brush passes over a brush, such as brush 2010c, the section of the nonwoven fabric aligned with and engaging the central brushing region including 2012 will be lofted, while the portions of the nonwoven fabric aligned with the two non-brushed regions 2013 will remain in a non-lofted (densified) state. Thus, the arrangement of multiple brushes and the arrangement of the bristles on each brush can be configured and positioned to form a selected pattern of lofted and non-lofted sections on the nonwoven fabric. The pressure of the bristles 2012 of each brushing device 2010 and the speed at which the bristles 2012 of each brushing device 2010 move relative to the surface of the nonwoven fabric (e.g., the speed at which the roller axle 2015 rotates) can be varied to thereby vary the presence and / or degree of lofting of the nonwoven fabric. As shown, the rotating brushes 2010a and 2010b rotate in a counter-rotating direction relative to the movement of the nonwoven fabric. The bristles 2012 in this embodiment or any other embodiment disclosed herein can be nylon bristles or any other type of bristles. Although the mechanical manipulator is shown and described herein as including a brush, the mechanical manipulator can be any structure, machine, system, or device configured to manipulate, backcomb, and / or promote lofting of the nonwoven fabric.

[0185] Referring to Figure 20C, an alternative brush 2010c is shown. The brush 2010e includes bristles that extend a first distance yl from the axle 2015 and bristles that extend a second distance y2 from the axle 2015. The bristles that extend the distance y2 are longer than those that extend the distance yl, so the second distance y2 is greater than the first distance yl. Between the bristles that extend the distance yl and the bristles that extend the distance y2, there are bristles that extend a distance intermediate between the distances yl and y2 such that the length of the bristles 2012 on the axle 2015 gradually and seamlessly (or continuously) decreases from the central bristle region 2017a to the side edges 2017b along the x-direction.

[0186] Referring to Figure 20D, an alternative brush 2010d is shown. Brush 2010d includes different bristle regions 2012, including regions 2044a and 2044b. Each bristle region varies in at least one aspect. For example, bristles 2012 can vary between regions 2044a and 2044b in bristle length, bristle width, bristle packing density (i.e., number of bristles per unit area of ​​the mandrel face), bristle composition, and bristle stiffness.

[0187] Referring again to FIG. 20 , in operation, nonwoven fabric 2004 is unwound from spool 2002 and fed into nonwoven fabric manipulator 2003. Within nonwoven fabric manipulator 2003, nonwoven fabric 2004 operatively engages first roller 2008, which feeds nonwoven fabric 2004 onto second roller 2014. While traveling over second roller 2014, bristles 2012 of brushing device 2010a engage and manipulate nonwoven fabric 2004. As shown, mandrel 2015 rotates in a first direction and second roller 2014 rotates in the opposite direction in cross section. The rotation of mandrel 2015 rotates bristles 2012 in a direction opposite to the movement of the nonwoven fabric around second roller 2014. The bristles 2012 thus at least partially bulk the nonwoven fabric 2004 in at least selected locations. The at least partially bulked nonwoven fabric 2016 is then fed from the second roller 2014 to the third roller 2019. While traveling over the third roller 2019, the bristles 2012 of the brushing device 2010b engage and manipulate the nonwoven fabric 2004. As shown, the mandrel 2015 rotates in a second direction and the third roller 2019 rotates in a first, opposite direction. The rotation of the mandrel 2015 rotates the bristles 2012 in a direction opposite to the movement of the nonwoven fabric 2016 around the third roller 2019. The bristles 2012 thus further bulk the nonwoven fabric 2016 in at least selected locations to form a bulked nonwoven fabric 2018. As shown, the bristles 2012 of the second brush 2010b engage and contact a first side of the nonwoven, while the bristles 2012 of the first brush 2010a engage and contact a side of the nonwoven opposite the first side. From the third roller 2019, the lofted nonwoven 2018 is fed to a fourth roller 2020 where it exits the nonwoven manipulator 2003. From the fourth roller 2020, the lofted nonwoven 2018 is fed to a spool 2022 for collection thereon. In some aspects, the lofted nonwoven 2018 is fed from the nonwoven manipulator 2003 directly into a system or apparatus for forming an absorbent core composite.For example, the lofted nonwoven 2018 can be fed into an apparatus for depositing absorbent material therein and / or for bonding other nonwovens to the lofted nonwoven 2018. Figure 21 is a photograph depicting an exemplary lofting system.

[0188] Bulking - Mechanical and Thermal Bulking Systems FIG. 23 illustrates an alternative bulking system 2300. The bulking system 2300 is substantially similar to the bulking system 2000 illustrated in FIG. 20, with like reference numerals indicating like parts. In addition to the mechanical operations illustrated and described with reference to FIG. 20, the bulking system 2300 includes heat treating the nonwoven fabric to promote bulking of the nonwoven fabric. In the embodiment illustrated in FIG. 23, the heat treating is accomplished using a hot air nozzle 2033 and a cold air nozzle 2031. However, any number of configurations can be used to heat treat the nonwoven fabric to increase and / or decrease the temperature of the nonwoven fabric to promote bulking of the nonwoven fabric. As illustrated, the hot air nozzle 2033 is incorporated into the nonwoven fabric manipulator 2003 and inserted between the first roller 2008 and the first brush 2010a. The hot air nozzle 2033 applies a heated air stream onto the nonwoven fabric 2004 before the nonwoven fabric is manipulated by the first brush 2010a. The heated air can be at a temperature higher than ambient temperature, such as 80°C or higher. Heating the nonwoven fabric 2004 can make the fibers of the nonwoven fabric 2004 softer compared to the nonwoven fabric 2004 before heating. Thus, brushing the heated nonwoven fabric achieves a higher degree of lofting of the nonwoven fabric (i.e., a more significant decrease in bulk density and a more significant increase in void volume) due at least in part to the fibers being softer to manipulation by the bristles 2012. As shown, the cold air nozzle 2031 is incorporated into the nonwoven fabric manipulator 2003 and inserted between the third roller 2019 and the fourth roller 2020 after the second brush 2010b. The cold air nozzle 2031 applies a cold air stream onto the bulked nonwoven 2018 after the nonwoven has been manipulated by the first brush 2010a and the second brush 2010b. The cold air is at a lower temperature than that of the heated air nozzle 2031, and can be lower than ambient temperature. The cold air serves to cool the nonwoven prior to further processing of the nonwoven. In some aspects, focused IR can be used to selectively heat sections of the NW web, allowing for selective bulking of sections of the NW web.

[0189] In some aspects, the high loft nonwoven fabric can be "printed" by thermal and / or mechanical means to have a desired pattern of lofted and non-lofted sections. The thermal and / or mechanical means can bulk the nonwoven fabric continuously or intermittently.

[0190] 20 and 23 show lofting sections in the machine direction, in some aspects lofting sections or lanes can be formed in the cross direction. For example, the brush device can have sections without bristles in the cross direction, or the bristles can intermittently engage the nonwoven, such that some cross-directional portions of the nonwoven are lofted and some are not.

[0191] In some aspects, one or more parameters of a system or process for bulking a nonwoven fabric can be varied to alter one or more aspects of the bulking. For example, aspects of the bulking that can be varied include, but are not limited to, the location of the bulking in the x-direction, y-direction, and / or z-direction, the degree of bulking (i.e., the degree to which bulk density is reduced and the degree to which void volume is increased). Aspects of a bulking system or process that can be varied include, but are not limited to, the speed at which the brush moves relative to the nonwoven fabric, the brush bristle thickness, the brush bristle length, the brush bristle material, the brush bristle spacing, the spacing between the brush bristles and the nonwoven fabric, the brush bristle pattern, the number of brushes used during bulking, the temperature of the heated air from the hot air nozzle, the velocity of the heated air from the hot air nozzle, the distance between the hot air nozzle and the nonwoven fabric, and the number of hot air nozzles used during bulking.

[0192] Increased bulk - Increased loft and SAP retention Bulking a nonwoven web can result in an increase in the loft of the nonwoven web. Furthermore, bulking reduces bulk density and increases void volume, thereby "opening" the nonwoven fibrous web by increasing the distance between each of the individual fibers of the nonwoven fibrous web. Such opening of the fibrous web increases the softness and compressibility of the nonwoven web compared to the nonwoven web before opening.

[0193] Such incisions in the nonwoven web allow a larger amount of absorbent material (e.g., SAP) to be incorporated into the nonwoven web compared to the amount of SAP that could be incorporated into the nonwoven web prior to bulking, because more SAP can penetrate and fit into the more open fibrous matrix of the nonwoven web. This allows the SAP to become more fully intermixed with the fibers of the nonwoven web compared to the nonwoven web prior to incision. Thus, more SAP is entangled with the nonwoven fibers than would be entangled if the nonwoven web were not subjected to such incisions. The SAP is at least partially immobilized due to entanglement within the fibers of the nonwoven web. In some aspects, incisions in the nonwoven web increase the extent and / or amount of such SAP immobilization within the fibrous web. Therefore, the amount of adhesive, such as a hot melt adhesive (HMA), required to immobilize the SAP within the nonwoven web can be reduced or eliminated. For example, the amount of HMA can be reduced by 10% to 50% by weight compared to the amount required without bulking. High SAP retention within the expanded nonwoven fabric allows the absorbent core composite to exhibit high fluid uptake rates, at least in areas of the absorbent core composite where the lofted sections of the nonwoven fabric contain SAP.

[0194] In some aspects, bulking the nonwoven fabric results in a decrease in the bulk density of the nonwoven fabric of 5% to 50%, 10% to 40%, 15% to 30%, or 18% to 25% compared to the bulk density of the nonwoven fabric before bulking. In certain embodiments, bulking the nonwoven fabric results in a decrease in the bulk density of the nonwoven fabric of at least 5%, at least 10%, at least 15%, at least 18%, at least 20%, or at least 25%, or about 24%, or about 27% compared to the bulk density of the nonwoven fabric before bulking.

[0195] In some aspects, bulking the nonwoven fabric results in an increase in the void volume of the nonwoven fabric of 5% to 75%, 10% to 60%, 15% to 50%, 20% to 40%, or 25% to 35% compared to the void volume of the nonwoven fabric before bulking. In some aspects, bulking the nonwoven fabric results in an increase in the void volume of the nonwoven fabric of at least 5%, at least 10%, at least 20%, at least 30%, at least 40%, or at least 45%, or about 37%, or about 45% compared to the void volume of the nonwoven fabric before bulking.

[0196] In some aspects, after bulking, the nonwoven is subsequently at least partially compressed, thereby reducing or eliminating bulk. In some such embodiments, SAP is added to the bulked high-loft nonwoven prior to its compression, e.g., immediately after bulking. After bulking, subsequent processing or associated final packaging of the BBNW, associated absorbent core composite, associated absorbent article (e.g., diaper) can at least partially compress the BBNW, absorbent core composite, and / or absorbent article, such that the bulk density of the BBNW is at least partially increased and the void volume of the BBNW is at least partially decreased. In some embodiments, the BBNW, even after such subsequent processing, has a lower density and a larger void volume compared to the BNW prior to bulking. Thus, at least some of the bulking remains in the final product, aiding product performance. Regardless of whether any of the bulking remains in the final product, the bulking allows for increased entanglement of the SAP within the fibers of the BNW during production of the absorbent core composite.

[0197] Bulking - Example - Brushing two nonwoven fabrics Referring to Figures 22A and 22B, two breathable bonded nonwoven fabrics are brushed in the system of Figures 20 and 21.

[0198] Experimental Processing Parameters In these examples, material processing was carried out under ambient conditions at a temperature of 16°C and 40% relative humidity (RH) without external heating or ambient conditions of material wetting. All materials were adapted to these ambient conditions before testing. The processing parameters used for these examples included: (1) nonwoven web feeding at 30 gear, (2) brush treatment at 24 gear, (3) a 4:5 (i.e., 24:30) ratio of nonwoven web to brush treatment, and (4) an operating speed (manually driven) of approximately 5 m / min. The sample nonwoven used for the first example was ADL30 Hua Yi ADL30 / PPT 30g / m 2 The sample nonwoven fabric used for the first example was ADL50 Hua Yi ADL50 / PPT 50g / m 2 It was.

[0199] Determining Web Density and Basis Weight An example of how the thickness for a high-bulk nonwoven fabric is determined can be found in WSP120.2.R4 (EDANA). An example of how the basis weight for a high-bulk nonwoven fabric is determined can be found in WSP130.1.R4 (EDANA). The density of each sample was determined as follows: (1) Perforation punch, Hanolex 3295 φ50 mm, A19.63 cm 2 (2) The sample thickness [H] was determined using a digital indicator with a presser foot on a Mitutoyo 543-470B with a Kafer φ35 mm. (3) The sample mass [M] was determined by weighing on an analytical balance using a Radwag AS220 / C / 2. (4) ρ was determined as the sample density [g / cm 3 ] and A is the sample area [cm 2 The sample web density [ρ] was calculated according to the formula ρ = M / (A × H), where M is the sample mass [g] and H is the sample thickness [cm]. The sample punch was 19.63 cm 2 In this case, the unit of ρ is g / cm 3 = g / cc. MA is the mass per unit area of ​​the sample [g / m 2 ] and A is the sample area [cm2 ], and M is the sample mass [g], the calculation formula is MA = M / A × 10 6 The web basis weight was determined according to the following.

[0200] Determination of void volume Void volume (VV) or porosity (φ) is directly proportional to density (ρ), therefore, reducing bulk density will increase void volume. Web porosity (void volume) can be determined according to the formula φ=M2-M1, where φ is the porosity or void volume of the sample [g], M1 is the sample mass [g], and M2 is the sample mass when the void volume is filled [g].

[0201] In the first example, 50 g / m 2 The first acquisition distribution layer (ADL) ADL50 was brushed, having a basis weight (weight per unit area) of 0.10 g / cm. Prior to brushing, the ADL50 had a basis weight (weight per unit area) of 0.10 g / cm, as indicated by the "#1 Pretreatment" data plotted in FIG. 22A. 3 Lower than 0.09g / cm 3 Higher than (approximately 0.099 g / cm 3 ) bulk density and 0.10 mL / cm 2 Less than 0.09 mL / cm 2 greater than (approximately 0.099 mL / cm 2 After the brushing treatment, the bulk density and void volume were determined again. After brushing, the ADL50 was about 0.075 g / cm, as indicated by the "#1 Post-Treatment" data plotted in Figure 22A. 3 and a bulk density of 0.075 mL / cm 2 The first example had a loss in process (LIP) of 0.03%, i.e., 0.03% of the fibers were lost from the NW during bulking.

[0202] In the second example, 30 g / m 2A second acquisition distribution layer (ADL) ADL30 was brushed, having a basis weight (weight per unit area) of 0.08 g / cm. Prior to brushing, ADL30 had a basis weight (weight per unit area) of 0.08 g / cm, as indicated by the "#2 Pretreatment" data plotted in FIG. 22B. 3 Lower than 0.06g / cm 3 Higher than (approximately 0.07 g / cm 3 ) bulk density and 0.08 mL / cm 2 Less than 0.06 mL / cm 2 greater than (approximately 0.07 mL / cm 2 After the brushing treatment, the bulk density and void volume were determined again. After brushing, the ADL30 had a bulk density of 0.06 g / cm, as designated by the "#2 Post-Treatment" data plotted in Figure 22B. 3 Lower than 0.05g / cm 3 Higher bulk density than 0.06 mL / cm 2 Less than 0.05 mL / cm 2 Thus, brushing resulted in a decrease in bulk density of ADL30 by about 27% and an increase in void volume of ADL30 by about 37%.

[0203] Figures 22C and 22D are scanning electron microscope (SEM) images of the ATNW before and after bulking, respectively, and it is clear from Figures 22C and 22D that the void volume of the nonwoven fabric has increased and the bulk density has decreased.

[0204] Density and void volume measurements were determined according to the standards set forth by EDANA. Thickness of the nonwoven sheets was measured using a digital micrometer applying a standard amount of pressure to the material. Basis weight was measured by cutting a nonwoven sample to a standard size (100 mm diameter circle) using a sample cutter and then weighing the sample.

[0205] Bulking - Alternative Systems Figure 23A shows an alternative system 2300a for bulking a nonwoven fabric, where like reference numbers refer to like elements with respect to Figures 20 and 23. In system 2300a, brushes 2010a and 2010b simultaneously brush the top and bottom surfaces of nonwoven fabric 2004. Brushes 2010a and 2010b rotate in opposite directions. Brushes 2010a and 2010b can be configured to rotate at the same speed or at different speeds.

[0206] FIG. 23B illustrates an alternative system 2300b for bulking nonwoven fabrics, where like reference numerals refer to like elements with respect to FIGS. 20, 23, and 23A. In system 2300b, a first nonwoven fabric 2004 is simultaneously brushed by brushes 2010a and 2010b. Brushes 2010a and 2010b can rotate in opposite directions or in the same direction. Brushes 2010a and 2010b can be configured to rotate at the same or different speeds. A second nonwoven fabric 2004a is fed through roller 2002a to roller 2020a, with brush 2010a brushing only one side of nonwoven fabric 2004a. A third nonwoven fabric 2004b is fed through roller 2002b to roller 2020b, with brush 2010b brushing only one side of nonwoven fabric 2004b. After brushing, nonwoven fabric 2004 is fed to rollers 2020a and 2020b where it is combined with nonwoven fabrics 2004a and 2004b to form an at least partially lofted composite high loft nonwoven fabric 2018a.

[0207] Figure 23C shows an alternative system 2300c for bulking a nonwoven fabric, where like reference numerals represent like elements with respect to Figures 20, 23, 23A, and 23B. In system 2300c, nonwoven fabric 2004c is fed through rollers 2002a and 2002b and rollers 2019c and 2019d to rollers 2020a and 2020b. Nonwoven fabric 2004d is fed through roller 2002c to brush 2010a and roller 2019a. After the surface of nonwoven fabric 2004d is brushed by brush 2010a, the brushed nonwoven fabric 2004d is fed to rollers 2020a and 2020b, where nonwoven fabric 2004d is combined with nonwoven fabric 2004c. Nonwoven fabric 2004e is fed through roller 2002d to brush 2010b and roller 2019b. After the surface of nonwoven fabric 2004e is brushed by brush 2010b, brushed nonwoven fabric 2004e is fed to rollers 2020a and 2020b, where nonwoven fabric 2004e is combined with nonwoven fabric 2004c and nonwoven fabric 2004d. System 2300c includes absorbent material distributor 2051 (e.g., a SAP distributor) positioned to distribute absorbent material onto the lofted surfaces of both nonwoven fabric 2004d and nonwoven fabric 2004e before combining nonwoven fabrics 2004d and 2004e with nonwoven fabric 2004c. Absorbent material distributor 2051 includes distributors 2053 and 2055 for dispensing absorbent material from a hopper of distributor 2051 onto nonwovens 2004d and 2004e. Rollers 2020a and 2020b can be actuated to compress nonwovens 2004c, 2004d, and 2004e together with the absorbent material trapped therein to form lofted nonwoven composite 2018b.

[0208] Figure 23D shows an alternative system 2300d for bulking a nonwoven fabric, where like reference numerals represent like elements with respect to Figures 20, 23, 23A, 23B, and 23C. In system 2300d, nonwoven fabric 2004f is fed through rollers 2002a and 2002b and rollers 2019a and 2019b to rollers 2020a and 2020b. Nonwoven fabric 2004g is fed through roller 2002c to brush 2010a and roller 2014a. After the surface of nonwoven fabric 2004g is brushed by brush 2010a, the brushed nonwoven fabric 2004g is fed to rollers 2020a and 2020b, where nonwoven fabric 2004g is combined with nonwoven fabric 2004f. Nonwoven fabric 2004h is fed through roller 2002d to brush 2010b and roller 2014b. After the surface of nonwoven fabric 2004h has been brushed by brush 2010b, brushed nonwoven fabric 2004h is fed to rollers 2020a and 2020b, where nonwoven fabric 2004h is combined with nonwoven fabric 2004f and nonwoven fabric 2004g. System 2300d includes absorbent material distributor 2051 positioned to distribute absorbent material onto the lofted surfaces of both nonwoven fabrics 2004g and 2004h prior to combining nonwoven fabrics 2004g and 2004h with nonwoven fabric 2004f. Rollers 2020a and 2020b can be actuated to compress nonwovens 2004f, 2004g, and 2004h together with the absorbent material trapped therein to form lofted nonwoven composite 2018c.

[0209] Figure 23E illustrates an alternative system 2300e for bulking a nonwoven fabric, where like reference numerals represent like elements with respect to Figures 20, 23, 23A, 23B, 23C, and 23D. System 2300e is identical to system 2300d shown in Figure 23E except for the addition of brushes 2010c and 2010d positioned to brush and bulk nonwoven fabric 2004i before it is fed to rollers 2020a and 2020b to combine with brushed nonwoven fabrics 2004j and 2004k to form bulked nonwoven composite 2018d. Thus, nonwoven fabric 2004i is bulked on both its top and bottom surfaces, and nonwoven fabrics 2004j and 2004k are each bulked on only one surface.

[0210] Although the SAP applicator is shown as including a hopper, in some aspects, an intermittent 3D vibratory printing tube, an air stream, or a continuous vibratory feed is used to deposit the SAP onto the nonwoven. Although not shown, heat treatment can be incorporated at any point within such systems, including upstream and / or downstream of the brushes in systems 2300a, 2300b, 2300c, 2300d, and 2300e. In some aspects, any of systems 2000, 2300, 2300a, 2300b, 2300c, 2300d, and 2300e can be incorporated into an existing system for forming an absorbent core composite.

[0211] Bulking of the nonwoven can be performed upstream of where SAP is applied to the bulked nonwoven, for example, at any point in the production of the absorbent core composites disclosed herein between the unwinding of the densified (unbulked) nonwoven and the application of the SAP. For example, referring to FIG. 24, bulking can occur at point "2499." FIG. 24 shows a system 2400 for forming an absorbent core composite 2410. A nonwoven 2420 is unwound from a spool or roller 2401a and combined with a nonwoven 2421 unwound from a spool or roller 2401b. A hot melt adhesive HMA is applied at 2422a, followed by the application of SAP at 2423a. Additional nonwoven 2499 is unwound from spool or roller 2401c and has an HMA applied to it at 2422b, which is then applied to the top surface of nonwoven 2424. This application is followed by the application of an HMA at 2422c and then the application of an SAP at 2423b. Additional nonwoven layer 2430 is unwound from spool or roller 2401d and has an HMA applied to it at 2422d, which is then combined with nonwoven 2424. An HMA is then applied at 2422e, after which an embossed pattern is applied to the composite layers to form absorbent core composite 2410, which is collected on spool or roller 2401e.

[0212] In any of the bulking processes disclosed herein, deposition of the SAP onto the bulked nonwoven web is followed by a residence time to allow the SAP to entangle within the fibers of the BBNW. Entanglement of the SAP within the fibers can be facilitated by gravity alone (when the SAP is dispensed onto the NW web from a height), mechanical means (vibration, vacuum), compression (at the risk of densifying the BBNW), or a combination thereof.

[0213] In some aspects, bulking is performed after SAP is deposited on the NWs. For example, SAP can be deposited on the NWs, followed by heating of the NWs. In some embodiments, bulking is performed before the addition of any adhesive to the NWs and / or SAP, since adhesives can reduce the degree of "bulking" or prevent "bulking." Bulking performed after SAP deposition can be performed using heating alone, since brushing can risk delaminating the deposited SAP. For example, SAP can be applied to the NWs, followed by thermal bulking of the NWs, and then followed by the addition of adhesive to the NWs and / or SAP.

[0214] In some aspects, after deposition of the SAP on the BBNW and before or at the time the BBNW is incorporated into the chassis of the absorbent article, the BBNW is inverted. This inversion can be performed, for example, to avoid positioning the SAP layer directly below the topsheet. By inverting the top BBNW, the BBNW layer is placed between the topsheet and the first SAP layer. Such an arrangement provides additional void volume and NW material between the first SAP layer and the user, allowing for more rapid absorption and a drier feeling on the user's skin, and also provides increased comfort to the user, as SAP particles can be hard and uncomfortable when positioned close to the skin.

[0215] Material placement and adjustment In any of the embodiments of the absorbent core composite disclosed herein, the locations of the components of the absorbent core composite can be arranged to impart fluid handling properties and functions, such as fluid flow, fluid absorption, and fluid distribution properties and functions, to the absorbent core composite. The nonwoven fabric layers and absorbent material layers within the absorbent core composite, the sections within each respective nonwoven fabric layer or absorbent material layer, and the absolute and relative positions of sections within one layer relative to sections within another layer can be arranged to impart such desired fluid handling properties and functions. The locations of NW, BNW, BBNW, slit NW, SAP-containing layers, SAP-containing lanes, and SAP-free lanes can be selectively arranged within the absorbent core composite.

[0216] Material Placement and Adjustment - SAP Fluid Handling For example, SAP-containing layers or lanes can be positioned at expected wetting paths or areas. To handle fluid flow in the z-direction (thickness of the absorbent core composite), SAPs can vary within and / or from one absorbent material layer to another, such that the permeability of the SAPs within the absorbent core composite is highest at the top, bodyside of the absorbent core composite and decreases to a lowest level of permeability at the bottom, opposite the bodyside of the absorbent core composite. For example, with reference to FIG. 17, SAPs contained within absorbent material layer 1702a can have a higher permeability than SAPs contained within absorbent material layer 1702b. Furthermore, a gradient of SAPs with varying properties can exist within a single absorbent material layer, such that SAPs contained on the top, bodyside side of an absorbent material layer (e.g., 1702a) have a higher permeability than SAPs contained in the opposite side of the absorbent material layer (e.g., the bottom or backside of layer 1702a).

[0217] Similarly, to handle fluid flow in the z-direction, the SAPs can vary within and / or from one absorbent material layer to another so that the absorption rate of the SAPs within the absorbent core composite is lowest (slowest) at the top, body-side of the absorbent core composite and increases to a highest level of absorption rate (fastest) at the bottom, opposite the body-side of the absorbent core composite. Furthermore, the SAPs can vary within and / or from one absorbent material layer to another so that the absorption capacity of the SAPs within the absorbent core composite is lowest at the top, body-side of the absorbent core composite and increases to a highest level of absorption capacity at the bottom, opposite the body-side of the absorbent core composite, providing maximum absorption efficiency.

[0218] Material Placement and Conditioning - Nonwoven Fluid Handling To handle fluid flow in the z-direction of the absorbent core composite, the nonwoven layers of the absorbent core composites disclosed herein can be positioned such that the NW layer positioned in the wetting path has a higher void volume compared to the void volume of the NW layer positioned at or near the bodyside of the absorbent core composite. For example, referring to FIG. 17, nonwoven layers 1704a and / or 1704b can have a larger void volume than nonwoven layer 1704c. The larger void volume in the bodyside nonwoven layer allows for fluid handling of the initial burst of fluid infiltration and fluid distribution within the nonwoven layer. The relative void volumes can be imparted by selective placement of the NW and BNW and / or selective lofting of the NW and / or BNW layers.

[0219] Material placement and adjustment - Nonwoven capillary profile formation Capillary action is a measure of a material's ability to allow fluids to flow through tiny pores and channels (capillaries) within itself. Capillary action allows fluids to flow in the x and y directions, sometimes called intracapillary movement.

[0220] In some embodiments, the capillarity of the fiber network of the nonwoven layer can be profiled in the xy plane of the layer. Such profiling can provide higher capillarity (relative to the fluid target area for wetting) at the side edges of the absorbent core composite. Such profiled capillarity allows fluid to flow (spread) continuously toward the side edges of the absorbent core composite for maximum utilization of the absorbent core composite. In some aspects, profiling of capillarity can be achieved by selectively densifying, bulking, and / or enhancing the wettability of the nonwoven fabric, such as by plasma and / or corona treatment of the nonwoven fabric. In some embodiments, a nonwoven layer with higher capillarity is disposed and / or positioned toward the bottom (opposite the body side) of the absorbent core composite to, for example, aid in capillary migration of fluid into the SAP in the lower absorbent material layer, enhancing fluid spreading within the core compared to fluid spreading that would occur in response to gravity alone, thereby enabling maximum core utilization during use of the absorbent core composite.

[0221] An example of a nonwoven fabric with profiled capillarity is shown in Figure 16C, where the lofted section 1665 has higher capillarity compared to the non-lofted section 1670. However, the non-lofted section 1670 has a higher bulk density compared to the lofted section 1665, which allows the non-lofted section 1670 to more easily prevent SAP particles from filtering through the nonwoven fabric than the lofted section 1665.

[0222] In use, SAP absorption is driven by osmotic pressure, which is slower than the freer fluid flow within the fiber network, which is driven by capillary action or fluid momentum. A higher basis weight (or void volume) nonwoven will allow more fluid to flow and spread within the core composite.

[0223] Exemplary Absorbent Core Composites 25, an exemplary absorbent core composite according to the present disclosure is shown. Absorbent core composite MLC 2500 has a body side 2502 and a back side 2504 opposite the body side 2502. MLC 2500 includes three nonwoven layers, including nonwoven layer 2510, nonwoven layer 2512, nonwoven layer 2514, and nonwoven layer 2516, and one absorbent material layer 2520.

[0224] The nonwoven layer 2510 can be a spunbound nonwoven layer, a tissue, or an apertured nonwoven. In some embodiments, the nonwoven layer 2510 is not and / or does not include SMS. The nonwoven layer 2510 can facilitate retention of SAP particles within the MLC 2500. In some embodiments, the MLC 2500 does not include a top nonwoven layer 2510.

[0225] Positioned below nonwoven layer 2510 is nonwoven layer 2512. Nonwoven layer 2512 can be or include a relatively high density fibrous layer of bicomponent fibers. In embodiments that do not include nonwoven layer 2510, nonwoven layer 2512 can form the top layer of MLC 2500. In some embodiments, there is no layer (nonwoven or absorbent material) positioned between nonwoven layer 2510 and nonwoven layer 2512. Nonwoven layer 2510 can be bonded to nonwoven layer 2512. In some embodiments, nonwoven layer 2512 is a non-bulking nonwoven or a densified breathable nonwoven.

[0226] Positioned below the nonwoven layer 2512 is a nonwoven layer 2514. The nonwoven layer 2514 can be or include a relatively low density fibrous layer of bicomponent fibers. That is, the bulk density of the nonwoven layer 2514 can be lower than the bulk density of the nonwoven layer 2412. The difference in density between the nonwoven layers 2512 and 2514 can be the result of increasing the loft of the nonwoven layer 2514, densifying the nonwoven layer 2512, selecting nonwoven layers having different densities, or a combination thereof. In some embodiments, there is no layer (nonwoven or absorbent material) positioned between the nonwoven layer 2512 and the nonwoven layer 2514. The nonwoven layer 2512 can be bonded to the nonwoven layer 2514. In some embodiments, the nonwoven layers 2512, 2514 are single unitary fibrous layers. In some such embodiments, nonwoven layer 2512 is a selectively densified region of a single unitary fiber layer. In some such embodiments, nonwoven layer 2514 is a selectively bulked region of a single unitary fiber layer.

[0227] Positioned below the nonwoven layer 2514 is a nonwoven layer 2516. The nonwoven layer 2516 can be or include an airlaid nonwoven, a tissue layer, an SMS nonwoven, a spunbound nonwoven, or a breathable nonwoven. In certain embodiments, the nonwoven layer 2516 is a relatively absorbent nonwoven, such as an airlaid nonwoven. In some embodiments, there is no layer (nonwoven or absorbent material) between the nonwoven layer 2514 and the nonwoven layer 2516. The nonwoven layer 2514 can be adhered to the nonwoven layer 2516.

[0228] The absorbent material layer 2520 includes or is composed of SAP particles. The SAP particles of the absorbent material layer 2520 are embedded within the nonwoven layer 2514. In some embodiments, the absorbent material layer 2520 is adhered to the fibers of the nonwoven layer 2514. In other embodiments, the absorbent material layer 2520 does not contain an adhesive, and the particles of the absorbent material layer 2520 are entangled within the fibers of the nonwoven layer 2514. The particles of the absorbent material layer 2520 are spaced apart within and intermingled with the fibers of the nonwoven layer 2514. As shown, the MLC 2500 includes SAP-free lanes 2550 centered between the lateral edges of the MLC 2500 and extending longitudinally along the MLC 2500.

[0229] 25 by laying down nonwoven layer 2516, laminating nonwoven 2514 on top of nonwoven 2516, depositing SAP within nonwoven layer 2514, laminating nonwoven 2512 on top of nonwoven 2514, and laminating nonwoven 2510 on top of nonwoven 2512. In other embodiments, this order is reversed, and thus the process includes laying down nonwoven 2510, laminating nonwoven 2512 to nonwoven 2510, laminating nonwoven 2514 to nonwoven 2512, depositing SAP within nonwoven 2514, and laminating nonwoven 2516 to nonwoven 2514.

[0230] In some embodiments, the high-loft nonwovens 2512 and 2514 of the MLC 2500 are formed in situ on the top surface of the airlaid nonwoven 2516 or on the top surface of the nonwoven 2510, depending on the production sequence. For example, bicomponent fibers can be deposited on the airlaid nonwoven 2516 (or nonwoven 2510) to form a fibrous web. As a result of fiber settling during web formation, a higher density bicomponent fiber region will form on the bottom surface of the deposited web, and a lower density bicomponent fiber population will form on top of the deposited web. This density gradient of bicomponent fibers within the deposited web will form a relatively high density bodyside bicomponent fiber layer (layer 2512) and a relatively low density garment-side bicomponent fiber layer (layer 2514). In some embodiments, the relatively high density bodyside bicomponent fiber layer (layer 2512) is positioned adjacent to the airlaid nonwoven 2516. In another embodiment, a relatively low density bodyside bicomponent fibrous layer (layer 2514 ) is positioned adjacent to the airlaid nonwoven 2516 .

[0231] Combination of different layers Each of the various embodiments of layers disclosed herein and their arrangements can be combined in various combinations to form various absorbent core composites according to the present disclosure. The absorbent core composites disclosed herein can include one or more nonwoven layers having various thicknesses, widths, lengths, SAP content, and SAP distribution among the different layers (e.g., as shown in and described with reference to Figures 4 and 4A-4M), one or more absorbent material layers with or without SAP-free lanes (e.g., as shown in and described with reference to Figures 6A-9), one or more nonwoven layers with slits (e.g., as shown in and described with reference to Figure 10), one or more loose fiber layers (e.g., as shown in and described with reference to Figures 13A-13C), one or more nonwoven layers that are either fully or section-bulked (e.g., as shown in and described with reference to Figures 15A-19B), one or more in-situ formed high loft nonwoven layers (e.g., as shown in and described with reference to Figure 25), or combinations thereof. Any such absorbent core composite may be embodied in an absorbent article such as that shown in and described with reference to Figures 1A to 1F.

[0232] Some embodiments relate to systems and / or processes for forming any of the absorbent core composites or articles disclosed herein. Such systems and / or processes may incorporate one or more of the features of the system shown in Figure 5, one or more of the features of the system shown in Figure 11, one or more of the features of the system shown in Figure 12, one or more of the features of the system shown in Figure 14, one or more of the features of the system shown in Figure 20, one or more of any of the features of the devices shown in Figures 20A-20C, one or more of the features of the system shown in Figure 21, one or more of the features of the system shown in Figure 23, one or more of the features of any or all of the systems shown in Figures 23A-23E, one or more of the features of the system shown in Figure 24, or any combination thereof.

[0233] A significant benefit of the resulting structure of many of the absorbent core composites described herein is a composite with increased loft (i.e., improved comfort and softer areas) and large void spaces from an otherwise flat core with little void volume. The increased void volume functions to provide temporary fluid retention and transport space. This space gives fluid within the confines of the core a place to temporarily reside during the few seconds it takes the superabsorbent material to activate and permanently trap the fluid. These voids or spaces act to allow fluid flow and facilitate the distribution of fluid secretions.

[0234] The foregoing descriptions have been presented for purposes of illustration and description. These descriptions are not intended to limit the present disclosure or embodiments thereof to the particular absorbent core composites and constructions or articles, devices, and processes disclosed. Various embodiments of the present disclosure are intended for applications other than diapers and training pants. The described absorbent core constructions can be incorporated into or with other garments, textiles, fabrics, and the like, or combinations thereof. The described absorbent core constructions can also incorporate different components. Furthermore, the described absorbent core composites can refer to the substrates (e.g., composite sheets) of such core composites prior to their individualization and incorporation into disposable absorbent articles (as separate absorbent core composites). These and other variations of the present disclosure will be apparent to those skilled in the relevant consumer product arts given the present disclosure. Consequently, variations and modifications commensurate with the above teachings, and the skill and knowledge of the relevant art, are within the scope of the present disclosure. The embodiments described and illustrated herein are further intended to explain the best mode for carrying out the present disclosure and to enable others skilled in the art to utilize the present disclosure and other embodiments with various modifications as required by a particular application or use of the present disclosure.

Claims

1. A multilayer absorbent core, A first nonwoven fabric on the main body side having an inner surface and an outer surface, A second nonwoven fabric having an inner surface and an outer surface, A superabsorbent material layer is included, The inner surface of the first nonwoven fabric includes a bulky nonwoven fabric. The inner surface of the second nonwoven fabric includes a bulky nonwoven fabric. A multilayer absorbent core wherein the superabsorbent material layer is positioned between the inner surface of the first nonwoven fabric and the inner surface of the second nonwoven fabric, or is embedded in the first nonwoven fabric, or is embedded in the second nonwoven fabric, or is a combination thereof.

2. The multilayer absorbent core according to claim 1, wherein at least one of the first nonwoven fabric and the second nonwoven fabric has a gradient void volume from the central crotch region of the multilayer absorbent core to the first and second longitudinal end regions of the multilayer absorbent core, and the void volume of the at least one nonwoven fabric in the central crotch region is greater than the void volume of the at least one nonwoven fabric in the first and second longitudinal end regions.

3. The multilayer absorbent core according to claim 1, wherein the multilayer absorbent core has a capillary action with a gradient in the Z direction, and the capillary action of the first nonwoven fabric is smaller than that of the second nonwoven fabric.

4. The multilayer absorbent core according to claim 2, wherein the first and second longitudinal end regions are densified.

5. The multilayer absorbent core according to claim 1, wherein the superabsorbent material layer has a plurality of spaced superabsorbent particle lanes and at least one lane where no absorbent material is present.

6. The superabsorbent material layer includes two spaced-apart superabsorbent particle lanes, The multilayer absorbent core according to claim 5, wherein the absorbent material-free lane is positioned to extend longitudinally between two superabsorbent particle lanes and between the first nonwoven fabric and the second nonwoven fabric, and does not contain superabsorbent material.

7. Furthermore, the multilayer absorbent core according to claim 6, comprising a plurality of additional absorbent material-free lanes that do not contain absorbent material, each of which is positioned adjacent to one of the two superabsorbent particle lanes and between the first nonwoven fabric and the second nonwoven fabric.

8. The multilayer absorbent core according to claim 6, wherein both the first nonwoven fabric and the second nonwoven fabric have a bulked inner surface, and at least some of the superabsorbent particles of the superabsorbent material layer are embedded in the bulked first nonwoven fabric and the second nonwoven fabric.

9. The multilayer absorbent core according to claim 1, wherein the first nonwoven fabric and the second nonwoven fabric have a gradient basis weight.

10. The multilayer absorbent core according to claim 9, wherein the basis weight of the first nonwoven fabric is greater than the basis weight of the second nonwoven fabric.

11. The multilayer absorbent core according to claim 1, wherein the width of the first nonwoven fabric is narrower than the width of the second nonwoven fabric.

12. The multilayer absorbent core according to claim 1, wherein the thickness of the first nonwoven fabric is greater than the thickness of the second nonwoven fabric.

13. Furthermore, it includes a third nonwoven fabric layer, The multilayer absorbent core according to claim 1, wherein the first nonwoven fabric is positioned between the third nonwoven fabric layer and the second nonwoven fabric.

14. The multilayer absorbent core according to claim 1, wherein the first nonwoven fabric includes a slit that coincides with the superabsorbent material layer, and the slit coincides with the central crotch region of the multilayer absorbent core.

15. Furthermore, a third nonwoven fabric, The present invention includes a second absorbent material layer positioned between the second nonwoven fabric and the third nonwoven fabric, The multilayer absorbent core according to claim 1, wherein the second absorbent material layer is embedded in the second nonwoven fabric, or embedded in the third nonwoven fabric, or a combination thereof.

16. The multilayer absorbent core according to claim 15, wherein the basis weight of the superabsorbent material layer is lighter than the basis weight of the second absorbent material layer.

17. The multilayer absorbent core according to claim 15, wherein the permeability of the superabsorbent material layer is higher than that of the second absorbent material layer.

18. The multilayer absorbent core according to claim 15, wherein the absorption rate of the superabsorbent material layer is slower than the absorption rate of the second absorbent material layer.

19. The multilayer absorbent core according to claim 15, wherein at least one of the superabsorbent material layer and the second absorbent material layer includes a plurality of absorbent material-containing lanes and at least one absorbent material-free lane, and the first nonwoven fabric, the second nonwoven fabric, and the third nonwoven fabric are bound together by embossed lines, the embossed lines coincide with the absorbent material-free lane.

20. The multilayer absorbent core according to claim 19, wherein the absorbent material-free lanes of the superabsorbent material layer and the second absorbent material layer are aligned in the Z direction from the first nonwoven fabric on the main body side to the third nonwoven fabric.

21. An absorbent core incorporated into a disposable absorbent article, The first nonwoven fabric, The second nonwoven fabric, The invention includes an absorbent material layer disposed between the first nonwoven fabric and the second nonwoven fabric, The absorbent material layer includes a plurality of absorbent material-containing lanes containing absorbent material, and an absorbent material-free lane which is a void in the absorbent material and is located between two of the absorbent material-containing lanes. The absorbent material is embedded in the first nonwoven fabric, or embedded in the second nonwoven fabric, or a combination thereof. An absorbent core comprising a bulky nonwoven fabric in which at least one of the first nonwoven fabric and the second nonwoven fabric coincides with the central groin region of the absorbent core.

22. The absorbent core according to claim 21, wherein at least one of the first nonwoven fabric and the second nonwoven fabric includes a plurality of slits, the plurality of slits aligning with superabsorbent particle-containing lanes of the absorbent material layer.

23. Furthermore, the absorbent core according to claim 21, having a free fiber layer containing free fibers, wherein the free fibers are positioned between the first nonwoven fabric and the second nonwoven fabric, and the free fibers include a plurality of individual fibers that are not bound to each other.

24. The absorbent core according to claim 21, wherein the second nonwoven fabric comprises one or more sections of a non-bulky nonwoven fabric, the one or more sections of the non-bulky nonwoven fabric having a higher bulk density and a smaller void volume than the bulky nonwoven fabric.

25. The absorbent core according to claim 24, wherein the bulky nonwoven fabric has a bulk density 5% to 50% lower than the bulk density of one or more sections of the nonbulky nonwoven fabric, and has a void volume 5% to 75% larger than the void volume of one or more sections of the nonbulky nonwoven fabric.

26. The absorbent core according to claim 24, wherein the absorbent material is positioned between the first nonwoven fabric and the second nonwoven fabric and embedded in the bulky nonwoven fabric.

27. The absorbent core according to claim 21, wherein the second nonwoven fabric includes a plurality of lanes in which bulky nonwoven fabrics and non-bulky nonwoven fabrics are arranged alternately, and the plurality of lanes extend along the longitudinal centerline of the absorbent core.

28. An absorbent core incorporated into a disposable absorbent article, The first nonwoven fabric, The second nonwoven fabric, The material includes an absorbent material layer comprising an absorbent material disposed between the first nonwoven fabric and the second nonwoven fabric, The second nonwoven fabric includes a bulky nonwoven fabric that coincides with the central groin region of the absorbent core. The absorbent material is an absorbent core embedded in the bulky nonwoven fabric.

29. The absorbent core according to claim 28, wherein the first nonwoven fabric includes a bulky nonwoven fabric.

30. The absorbent core according to claim 28, wherein the absorbent material comprises superabsorbent particles, and a lane without superabsorbent particles extends through the absorbent material between the first nonwoven fabric and the second nonwoven fabric.

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