Absorbent core with enhanced fit and absorbency

Abstract

To provide an absorbent core that is capable of achieving a comfortable fit for a user, without sacrificing a degree of absorbency of the core.SOLUTION: An absorbent core is disclosed. The core includes a first absorbent core construction having multiple spaced sections of a fibrous construction having a fiber structure. A first nonwoven sheet is positioned above the fibrous construction. A second nonwoven sheet is positioned below the fibrous construction. The first nonwoven sheet is coupled with the second nonwoven sheet at locations between adjacent sections of the multiple spaced sections of the fibrous construction. Absorbent material is disposed within the fiber structure between the first and second nonwoven sheets.SELECTED DRAWING: Figure 4A

Description

Technical Field

[0001] 〔Cross - Reference to Related Applications〕 This application claims the benefit of U.S. Provisional Patent Application No. 62 / 780,781, filed Dec. 17, 2018, entitled “Absorbent Cores with Enhanced Fit and Absorbency,” which is incorporated herein by reference in its entirety.

[0002] The disclosure of the present invention generally relates to absorbent cores or absorbent core composites, disposable absorbent articles incorporating an absorbent core or core composite, and systems (devices) and methods for making such and other related products. Disposable absorbent articles to which the disclosure of the present invention is particularly applicable include baby diapers, training pants, adult incontinence products, and feminine hygiene products. The absorbent core composite is particularly suitable for providing a central absorbent structure for disposable absorbent garments that are worn to conform to the user's body structure.

Background Art

[0003] Typically, an absorbent core sacrifices fit for increased absorbency or sacrifices increased absorbency for better fit. For example, some absorbent cores are cut along their outer edges to produce an hourglass shape in order to provide a better fit. However, such cutting in the crotch region reduces the absorbent material concentrated in this important absorption zone, thereby sacrificing absorbency to achieve a better fit. Absorbent cores that are not cut in this way are thought to exhibit a higher degree of absorbency but will have an uncomfortable bulging fit between the user's thighs.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] [Non-Patent Document 1] Dunstan and White, J. Colloid Interface Sci., Vol. 111, p. 60, 1986. [Overview of the project] [Problems that the invention aims to solve]

[0006] It is desirable to have an absorbent core that can achieve a comfortable fit for the user without sacrificing the degree of absorption of the core. [Means for solving the problem]

[0007] Some embodiments of the disclosure of the present invention include an absorbent core having a longitudinal centerline and a transverse centerline that is transverse to the longitudinal centerline. The absorbent core includes a first absorbent core configuration. The first absorbent core configuration includes a plurality of transversely spaced fibrous configurations. Each fibrous configuration extends substantially parallel to or coincide with the longitudinal centerline, and each fibrous configuration includes a nonwoven fabric. A first nonwoven sheet is positioned on the first side of the fibrous configuration. A second nonwoven sheet is positioned on the second side of the fibrous configuration opposite to the first side of the fibrous configuration. The first nonwoven sheet is bonded to the second nonwoven sheet at a location between adjacent transversely spaced fibrous configurations. An absorbent material is placed within the nonwoven fabric of each fibrous configuration. The absorbent material is positioned between the first and second nonwoven sheets.

[0008] Some embodiments of the disclosure of the present invention include an absorbent article comprising an absorbent core and a chassis including a back sheet and a top sheet. The absorbent core is positioned between the top sheet and the back sheet and bonded to the back sheet. The absorbent core has a longitudinal centerline and a transverse centerline which is transverse to the longitudinal centerline. The absorbent core includes a first absorbent core configuration. The first absorbent core configuration includes a plurality of transversely spaced fibrous configurations. Each fibrous configuration extends substantially parallel to or coincident with the longitudinal centerline, and each fibrous configuration includes a nonwoven fabric. A first nonwoven sheet is positioned on the first side of the fibrous configuration, and a second nonwoven sheet is positioned on the second side of the fibrous configuration opposite to the first side of the fibrous configuration. The first nonwoven sheet is bonded to the second nonwoven sheet at a location between adjacent transversely spaced fibrous configurations. Absorbent material is placed within the nonwoven fabric of each fibrous configuration. The absorbent material is positioned between the first and second nonwoven sheets.

[0009] Some embodiments of the disclosure of the present invention include a method for creating a fibrous structure comprising a composite of an absorbent material and a nonwoven fabric. The method includes the step of providing a nonwoven fabric having a first surface and a second surface. The method includes the step of passing a forced airflow containing the absorbent material over and through the first surface of the nonwoven fabric. At least a portion of the absorbent material is trapped within the nonwoven fabric between the first surface and the second surface. The method includes the step of filtering at least a portion of the absorbent material through the nonwoven fabric at least partially such that a gradient distribution of particle size of the absorbent material is formed within the nonwoven fabric between the first surface and the second surface.

[0010] Some embodiments of the disclosure of the present invention include a system for introducing an absorbent material into a nonwoven fabric. The system includes a nonwoven fabric conveyor and a chamber including an input and an output. The nonwoven fabric conveyor crosses the chamber between the input and the output. A forced airflow generator is positioned to generate a forced air stream through the chamber. An absorbent material source is positioned to supply the absorbent material into the chamber.

[0011] Some embodiments of the disclosure of the present invention include a method for creating an absorbent core having a longitudinal centerline and a transverse centerline that is transverse to the longitudinal centerline. The method includes the steps of combining a nonwoven fabric with an absorbent material to form a fibrous structure, separating the fibrous structure into a plurality of fibrous structures, and bonding a first nonwoven sheet onto a first surface of the fibrous structure, wherein the plurality of fibrous structures are spaced apart laterally. The method includes the steps of positioning a second nonwoven sheet onto a second surface of the fibrous structure opposite to the first surface, and bonding the first nonwoven sheet to the second nonwoven sheet along bonding lines extending between adjacent, laterally spaced fibrous structures to form a first absorbent core structure. In some embodiments, the absorbent core is used to create an absorbent article by positioning the absorbent core within a chassis, including bonding the absorbent core to the back sheet between the back sheet and the top sheet of the chassis.

[0012] Some embodiments of the disclosure of the present invention include a roller for forming a wavy top sheet of an absorbent core. The roller includes a body, a roller surface, and grooves formed on the roller surface.

[0013] Some embodiments of the disclosure of the present invention include a system for making an absorbent core. The system includes a non-woven conveyor and a chamber including an input and an output, and the non-woven conveyor intersects the chamber between the input and the output. The system includes a forced air flow generator positioned to generate a forced air stream through the chamber and an absorbent material source positioned to provide absorbent material into the chamber. The system includes an upper non-woven sheet conveyor positioned to convey an upper non-woven sheet, and a bonding roller positioned to receive the upper non-woven sheet from the upper non-woven sheet conveyor and the non-woven from the non-woven conveyor and arranged to combine the non-woven with the upper non-woven sheet.

Brief Description of the Drawings

[0014] [Figure 1] Perspective views of an absorbent core composite, an article, and a disposable absorbent article that can incorporate the core composite therein, each according to the disclosure of the present invention. [Figure 2] Top view of the disposable absorbent article of FIG. 1 in a flat and extended condition. [Figure 3] Exploded assembly view of the disposable article of FIG. 1. [Figure 4A] Perspective view of the absorbent core in a flat configuration. [Figure 4B] Detailed view of the core of FIG. 4A. [Figure 5] Cross-sectional view of the absorbent core. [Figure 6] Cross-sectional view of an absorbent article including the absorbent core. [Figure 7] Longitudinal sectional view of an absorbent article including the absorbent core. [Figure 8] Perspective view of the core in a W-shaped configuration. [Figure 9A] Cross-sectional view of the W-shaped core in the central strand region. [Figure 9B] This is a cross-sectional view of the W-shaped core in the central groin area where the chassis back sheet is attached. [Figure 9C] Another cross-sectional view of the W-shaped core in the central groin area where the chassis back sheet is attached. [Figure 9D] This is a cross-sectional view of the W-shaped core in the central groin area where the chassis back sheet is continuously attached. [Figure 9E] This is a cross-sectional view showing the forces acting on the W-shaped core in the central hip region. [Figure 9F] This is a cross-sectional view of the W-shaped core at the central crotch region showing the unfixed raised edge, wing section, fixed fold, unfixed raised central fold, and air channel. [Figure 9G] This is a cross-sectional view of a W-shaped core incorporated into an absorbent article and worn by the user, where the top sheet conforms to the shape of the core. [Figure 9H] This is a cross-sectional view of a W-shaped core incorporated into an absorbent article and worn by the user, with the top sheet free from the bottom of the core. [Figure 10A] This figure shows a bulky nonwoven fabric with a gradient distribution of SAP and adhesive. [Figure 10B] This figure shows a bulky nonwoven fabric with a gradient distribution of SAP. [Figure 10C] This figure shows a bulky nonwoven fabric with a gradient distribution of SAP and adhesive. [Figure 10D] This figure shows a bulky nonwoven fabric with a gradient distribution of SAP and a trapping layer positioned beneath it. [Figure 10E] This diagram illustrates the exemplary fibrous structure preparation and SAP deposition sequence. [Figure 10F] This diagram illustrates the exemplary fibrous structure preparation and SAP deposition sequence. [Figure 10G] This diagram illustrates the exemplary fibrous structure preparation and SAP deposition sequence. [Figure 10H] This diagram illustrates the exemplary fibrous structure preparation and SAP deposition sequence. [Figure 11A] This is a perspective view of a two-component fiber. [Figure 11B] End view of a two-component fiber. [Figure 11C] This figure shows the adhesion of two-component fibers and the attachment of SAP to them. [Figure 11D] This figure shows the adhesion of two-component fibers and the attachment of SAP to them. [Figure 11E] This figure shows the adhesion of two-component fibers and the attachment of SAP to them. [Figure 11F] This figure shows the adhesion of two-component fibers and the attachment of SAP to them. [Figure 12A] This is a simplified diagram of the system and process for creating an absorbent core. [Figure 12B] This diagram illustrates the bulking of nonwoven fabrics. [Figure 12C] This diagram illustrates the bulking of nonwoven fabrics. [Figure 12D] This diagram illustrates the deposition and filtration of SAP onto a bulky nonwoven fabric via forced airflow. [Figure 12E] This diagram illustrates the process of cutting bulky nonwoven fabric into sections. [Figure 12F] This diagram illustrates the process of cutting bulky nonwoven fabric into sections. [Figure 12G] This diagram depicts a core having a nonwoven trapping sheet positioned beneath a bulky nonwoven sheet. [Figure 12H] This is a diagram illustrating a grooved forming roller, its various parts, and its use. [Figure 12I] This is a diagram illustrating a grooved forming roller, its various parts, and its use. [Figure 12J] This is a diagram illustrating a grooved forming roller, its various parts, and its use. [Figure 12K] This is a diagram illustrating a grooved forming roller, its various parts, and its use. [Figure 13] This is a simplified flowchart of the process for creating an absorbent core. [Figure 14] This is another simplified flowchart of the process for creating the absorbent core. [Figure 15] This is a simplified flowchart of the process for creating the pulp layer. [Figure 16]This is a graph showing the particle size distribution of SAP. [Figure 17A] This diagram illustrates the bulking of nonwoven fabrics. [Figure 17B] This diagram illustrates the bulking of nonwoven fabrics. [Figure 18] This diagram illustrates the process of cutting bulky nonwoven fabric into sections. [Figure 19] This is a detailed diagram of the process for creating the pulp-SAP layer. [Figure 20A] This is a diagram illustrating crepe-processed spunbond nonwoven fabric. [Figure 20B] This is a diagram illustrating crepe-processed spunbond nonwoven fabric. [Figure 20C] This is a diagram illustrating crepe-processed spunbond nonwoven fabric. [Figure 20D] This is a diagram illustrating crepe-processed spunbond nonwoven fabric. [Figure 20E] This is a diagram illustrating crepe-processed spunbond nonwoven fabric. [Figure 21] This is a schematic diagram of the process for forming an SAP-fiber composite by extruding fibers onto SAP. [Figure 22] This is a diagram of an absorbent core having laterally spaced sections with different SAP concentrations. [Figure 23] This is a diagram of an absorbent core having lanes with varying SAP concentrations along their longitudinal length. [Figure 24] This is a diagram of an absorbent core having lanes extending in the lateral and longitudinal directions for SAP concentration. [Figure 25] This is a diagram of an absorbent core having a pattern of SAP concentration arrangements, including SAP concentrations that extend at angles with respect to the lateral and longitudinal centerlines of the absorbent core. [Figure 26] This is a diagram of an absorbent core having a pattern of SAP concentration radiating from the central groin region of the core. [Figure 27] This is a diagram of an absorbent core having a pattern of SAP concentration radiating from the central groin region of the core. [Figure 28] This is a diagram of an absorbent core with a curved pattern of SAP concentration. [Modes for carrying out the invention]

[0015] The systems, apparatus, and methods disclosed and described in this invention generally relate to absorbent core composites and disposable absorbent articles incorporating them. Such disposable absorbent articles include infant diapers, training pants, adult incontinence products, and feminine hygiene articles. To facilitate the explanation of this invention, many embodiments relating to diapers will be described. The disclosure of this invention naturally extends to applications other than diapers.

[0016] For the purposes of describing the various aspects of the disclosure of the present invention, an absorbent core composite or configuration refers to an aggregated arrangement of multiple components or sections, including one or more sections or components composed of or containing absorbent material. Similar to the term “composite,” the term “configuration” can, in one aspect, refer to such an aggregated arrangement of multiple sections or components that together constitute an absorbent. Such an absorbent can then be incorporated into a disposable absorbent article or garment to provide an absorbent core to the article. In some diaper or training pants applications, another cover layer (e.g., nonwoven fabric or nonwoven tissue) may wrap around or lie on top of the absorbent core (and may be included when defining the absorbent core of the article). Furthermore, the absorbent article may provide one or more impermeable backing sheets, top sheets, and one or more acquisition / distribution layers (ADLs) and / or tissue layers around or adjacent to the absorbent core.

[0017] For certain applications, a preferred absorbent core configuration includes a primary or central absorbent structure positioned for initial acceptance (body side) in the groin area of ​​a disposable absorbent article. In designs employing multiple absorbent layers or absorbent cores, the primary absorbent structure may also be referred to as the upper absorbent layer, upper core, upper absorbent structure, or upper core layer.

[0018] In exemplary applications, the absorption structure is bordered by a fibrous structure or fibrous network; therefore, the upper or primary absorption structure may be referred to as a fibrous layer or fibrous structure.

[0019] As used herein, “NW” refers to nonwoven fabric. In certain applications, the upper core structure is preferably bordered and primarily composed of a bulky nonwoven fabric (also called a high-loft nonwoven fabric), such as an air-permeable nonwoven fabric. At least a portion of the nonwoven layers disclosed herein may be meltblown nonwoven fabrics, spunbond nonwoven fabrics, or any combination thereof (e.g., spunbond-meltblown-spunbond (SMS) nonwoven fabrics). Furthermore, each nonwoven layer disclosed herein may be a “tissue” or “tissue layer,” which is a cellulose-based (paper) nonwoven fabric, as opposed to a synthetic nonwoven fabric. The fibers of any nonwoven fabric disclosed herein may include, but are not limited to, fibers composed of polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polylactic acid (PLA), other polyolefins, their copolymers, and any combination thereof, including binary fibers. The fibers can be treated with a surfactant, which is a surface active material, to alter the surface tension of the fibers to make them hydrophilic. In some embodiments, the NW layer used in the absorbent core composite disclosed herein is selected based on the pore size of the fabric, the fiber wettability of the fabric, or a combination thereof.

[0020] When used herein, the density of nonwovens, including bulky nonwovens, is determined according to the following formula 1: density (ρ) = mass (m) / volume (v) = mass / (length (l) × width (w) × thickness (t)). The Nonwovens Association of America (INDA) and the Nonwovens Association of Europe (EDANA) provide test methods that enable those skilled in the art to determine density values ​​using the above formula 1, although these methods do not include specific methods for density. Test method NWSP 120.2.R0(15) established by INDA and EDANA provides means for measuring the thickness (t) of bulky nonwovens, also known as high-loft nonwovens. Test method NWSP 130.1.R0(15) established by INDA and EDANA provides means for measuring the mass or basis weight (bw) per unit area. The density can be determined when the thickness of the bulky nonwoven fabric and the mass per unit area of ​​the bulky nonwoven fabric are determined according to NWSP 120.2.R0(15) and NWSP 130.1.R0(15). Density (ρ)=m / v=m / (l×w×t) (Equation 1) Mass per unit area (bw) = m / (l × w) (Equation 2), therefore, ρ = bw / t (Equation 3)

[0021] As used herein, "BNW" refers to "bulky nonwoven fabric." Bulky nonwoven fabrics are thicker than non-bulky nonwoven fabrics at low to medium basis weights. Air-penetrating nonwoven fabrics are a type of bulky nonwoven fabric and refer to a method of manufacturing nonwoven fabrics in which hot air is blown onto a carded nonwoven fabric to heat-bond the fibers. Other types of bulky nonwoven fabrics include resin-bonded nonwoven fabrics and other carded nonwoven fabrics. As used herein, "bulky nonwoven fabric" can be hydrophilic but non-absorbent fibers and can be an open fiber network or web, and is provided therein. Furthermore, as used herein, bulky nonwoven fabric has a thickness of 100 μm to 10,000 μm (preferably 1,000 μm to 5,000 μm) and a basis weight of 15 g / m². 2 ~200g / m 2 (Preferably 20 g / m 2 ~80g / m 2The material is a fibrous web material having a basis weight of 0.01 g / cc to 0.3 g / cc (preferably 0.01 to 0.08 g / cc). Furthermore, this bulky nonwoven fabric will have an effective pore size of 300 μm to 2000 μm. The effective pore size is estimated from the web density, fiber diameter, and fiber density values ​​according to the Dunstan and White method (J. Colloid Interface Sci., Vol. 111, p. 60, 1986), in which case the effective pore size = 4 * (1-solid volume fraction) / (solid volume fraction * solid density * This is the specific area of ​​the solid.

[0022] As used herein, “crepe spunbond” refers to a crepe-processed thermoplastic nonwoven web that produces a bulky structure having substantial fiber looping between bonded areas of a base spunbond sheet. Crepe spunbond includes, but is not limited to, those disclosed in U.S. Patents 6,197,404, 6,150,002, 6,797,360, 6,673,980, and 6,838,154, each of which is incorporated herein by reference.

[0023] As used herein, “bulking” or “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 (porosity of the nonwoven web) and specific volume (i.e., the reciprocal of density) compared to the bulk density and void volume of the nonwoven fabric before “bulking.” After “bulking,” such a nonwoven fabric may be referred to herein as “bulked nonwoven fabric.”

[0024] As used herein, “BBNW” means nonwoven fabric, optionally, bulky nonwoven fabric that is at least partially bulked.

[0025] As used herein, “open fiber layer” refers to a fibrous structure having a relatively large pore diameter, i.e., a larger fiber gap than another fibrous structure having a smaller pore diameter. An “open” fiber layer has a lower fiber density (fewer fibers per unit volume) and / or finer fibers (lower denier) and / or fewer crimped fibers.

[0026] Any of the nonwoven fabrics disclosed herein can form the top sheet or cover layer of an absorbent core composite, the base layer or substrate or back sheet of an absorbent composite, the intermediate layer of an absorbent core composite (positioned between the top sheet and the back sheet), or any combination thereof.

[0027] As used herein, "fluff" generally refers to cellulose wood pulp made from pine. The base material for fluff is often supplied in the form of a cardboard-like sheet, which is then processed into fluff using a hammer mill.

[0028] As used herein, “dry integrity” refers to the structural and positional integrity of a core or article when it is in a dry state, such as during manufacturing, packaging, shipping, and storage.

[0029] As used herein, “wet integrity” refers to the structural and positional integrity of a core or article when it is in a wet state, such as when it is soiled during use.

[0030] As used herein, “structural integrity” refers to the ability of a core or a single component of an article to maintain its structure and not deform.

[0031] As used herein, “positional integrity” refers to the ability of a core or component of an article to maintain its structure and position relative to other components of the core or article (i.e., not to deform or move). For example, a SAP with wet integrity does not move within the core during swelling of the SAP.

[0032] As used herein, "SAP-free" and "absorbent material-free" refer to a surface area on a nonwoven substrate that lacks an absorbent material.

[0033] As used herein, “absorbent layer,” “absorbent material layer,” and “AML” refer to a layer comprising at least one absorbent material capable of absorbing and retaining at least some liquid. Any absorbent material disclosed herein may be or include SAP (superabsorbent polymer), which may consist of, for example, polyvinyl alcohol, polyacrylate, various grafted starches, or cross-linked sodium polyacrylate. Although described herein as particles, SAP may be in the form of particles, fibers, foams, webs, spheres, aggregates of regular or irregular shapes, and films. In some embodiments, SAP is combined with an absorbent matrix, which may be defibroused wood pulp or a similar material. In other embodiments, the SAP and the absorbent core composite as a whole lack an absorbent matrix. In some embodiments, at least one set of multiple SAP particles is mixed with at least one other particle. Such another non-SAP particle may include, but is not limited to, hot-melt adhesive particles, binder particles, spacer particles, or other particles. While "SAP" is used to refer to the absorbent material used in many of the specific embodiments shown and / or described in the disclosure of the present invention, it is understood that "SAP" in any such embodiment can be replaced with another absorbent material. For example, the "SAP-free lane" disclosed herein may be an "absorbent material-free lane." In some embodiments, the absorbent material used herein is selected based on its intrinsic superabsorbent properties, including gel bed permeability, absorption rate (vortex method), absorption capacity (CRC), and particle size.

[0034] In this specification, "absorbent structure" refers to a structure or composite or a part thereof that provides a fluid-retaining function to a layer or structure. For example, in some embodiments of an upper absorbent structure, a fibrous structure with SAP (or other absorbent material) deposited inside can form an absorbent structure, whereas a nonwoven sheet enclosing the fibrous structure with SAP (or other absorbent material) deposited inside does not constitute part of an absorbent structure.

[0035] When used herein, “SAP particle size” may be measured in terms of particle diameter. SAP particles can be spherical or flaky (clumped). Particle size can be determined by passing the SAP through a series of meshes / sieves with openings of different sizes. The particle size distribution of the entire mixture of SAP can be determined by measuring the weight of SAP passing through each mesh. A typical SAP can have a mixture of particles with diameters of approximately 80 to 800 microns. For example, Figure 16 shows the particle size distribution for many different superabsorbents. The SAPs disclosed herein can have particle sizes in the range of 45 to 850 microns, or 80 to 800 microns, or 100 to 700 microns, or 200 to 600 microns, or 300 to 500 microns. The particle size of the SAP granules disclosed herein may vary depending on a certain application. For example, a fibrous structure with a dense bottom layer or surface will capture finer SAP particles compared to a fibrous structure with a less dense bottom layer or surface, which will allow for internal filtration of finer SAP particles. In some embodiments, the SAP granules include SAP particles that are 150 microns or less, 100 microns or less, 80 microns or less, or 45 microns or less.

[0036] As used herein, “body side” or “side of the body” means the surface and / or side that faces the user’s body when the absorbent core composite is worn by the user (for example, when the absorbent core composite is incorporated into a diaper or other absorbent article worn by the user).

[0037] As used herein, “upstream” in relation to a process stage refers to a process stage that takes place chronologically before another stage. As used herein, “upstream” in relation to fluid flow within an absorbent core composite refers to a spatial and / or temporal location along the fluid flow path.

[0038] Some aspects relate to the deposition and filtration of SAP on, in, and / or through nonwoven fabrics, such as bulky nonwoven fabrics. The disclosure of U.S. Patent No. 2015 / 0045756, which is incorporated herein by reference in its entirety, provides a description relating to such deposition and filtration of SAP.

[0039] This specification, abstract, individual figures, or claims should not be construed as limiting the embodiments and uses disclosed herein. Rather, each of these parts of the disclosure of the present invention reveals one or more structural or material features that can be combined or incorporated with the basic configuration described above to define a unique embodiment or use. Furthermore, this basic configuration can be applied to or incorporated with various disposable absorbent articles, each of which conforms to one embodiment of the disclosure of the present invention. The same applies to systems, apparatus, and methods for making absorbent composites and disposable absorbent articles incorporating these composites. That is, systems, apparatus, and methods for making different absorbent composites as described above (including subsystems and sub-processes applied to the manufacture or formation of components) are also disclosed herein and provided according to the embodiments and uses of the disclosure of the present invention.

[0040] Absorbent core with enhanced fit and absorbency The disclosures of the present invention generally relate to absorbent cores or absorbent core composites, disposable absorbent articles incorporating absorbent cores or core composites, and systems, apparatus, and methods for manufacturing such products and other related products. Certain embodiments can also be applied to sanitary napkins and feminine hygiene products, etc. Specifically, the absorbent structures of the disclosures of the present invention can be incorporated into or together with various disposable absorbent articles to provide an absorbent mechanism in the final product. In one embodiment, the absorbent structure is an absorbent core composite employing a particularly effective absorbent structure having desirable structural (wet and dry) integrity and performance characteristics.

[0041] In one preferred embodiment, the absorbent structure utilizes a fibrous structure, more preferably, absorbent particles within or held by the fibrous network of the fibrous structure. In certain configurations, the core composite utilizes superabsorbent particles (SAP) as the primary absorbent material, and further utilizes a fibrous structure that provides a structure that maintains the SAP distribution, and provides an absorbent core section having wet and dry coherence with respect to the SAP distribution. Alternatively, in advantageous applications, spaced-out absorbent sections are provided, which readily conform to a desired "wearable" configuration and exhibit improved fluid management and body conformity properties. Most preferably, the absorbent particles are superabsorbent particles, and further preferably, the superabsorbent particles are distributed in the z-direction of the fibrous structure.

[0042] In one exemplary configuration, the fibrous structure or construction provides a relatively rigid support structure that exhibits integrity in both dry and wet conditions. In this context, the absorbent section is considered to have structural integrity and can maintain its shape and structure throughout manufacturing, packaging, wear, and subsequent absorption and retention of excrement. Furthermore, as described below, the absorbent core composite conforms to the user's biostructure and maintains such rigidity even while flexing and bending around a plurality of predetermined lines. SAP particles provide primary absorption functionality to reduce the "wet" load on the fibrous structure and help maintain structural integrity between and during dry and wet conditions. Moreover, in a preferred configuration, the core composite is provided by a plurality of spaced-out absorbent sections, which can be SAP fibrous sections (e.g., SAP bulky nonwoven fabric or crepe spunbond) or other absorbent structures. Each absorbent section has a thickness in the z-direction, a width in the transverse direction, and a longitudinal length that can extend between the front and rear waist regions. The gaps or flows between sections provide or include folds (or pivot lines) that allow the sections to pivot or rotate (preferably more than 12.5 degrees toward each other) before or during use. In certain embodiments, the forces resulting from fastening and positioning the article and core composite against or around the user's thigh or crotch cause the core composite to conform and take on a "W" shape (or act to reinforce or emphasize the W shape).

[0043] In these preferred configurations, the folds and folding shapes are pre-designed (or their location or alignment is pre-positioned), and their folding response is enhanced by several structural features, including the inclusion of channels or gaps between absorbent sections and the use of relatively rigid, longitudinally extending absorbent core sections. For example, the use of SAP particles dispersed in the z-direction facilitates the use of fibrous structures that are not burdened with the function of capturing and absorbing liquid and thus can more easily maintain structural integrity and morphology. Furthermore, the channels and folds are pre-positioned to fit or align with the thigh and crotch regions. The core composite includes transverse or lateral wing sections having a width of approximately 20% to 35% of the total width of the core, which align adjacent channels or folds with the thigh and help rotate intermediate sections or adjacent absorbent sections upward toward the crotch (in which case the centrally located fold pivots adjacent intermediate sections in the opposite direction to the wing sections, pushing inward toward the crotch). Similarly, the core composite can be fixed with a bond line or the like along or near the first bond line on the outside or to ensure a W-shape or W-fold shape. Thus, a preferred core composite has two wing-absorbing sections, two intermediate-absorbing sections, and three channels or folds between these sections.

[0044] Some embodiments relate to absorbent composites. The absorbent composite comprises a core composite having spaced-out absorbent sections (e.g., sections of BNW), with gaps or channels positioned between adjacent sections. The BNW sections contain SAP, which may have a gradient distribution within the BNW. The BNW may have a gradient density, facilitating the formation of the SAP gradient. In some such embodiments, the absorbent core has a W-shaped configuration. The gaps or channels provide folds, around which the core can fold itself into the W-shaped configuration.

[0045] The core may include first and second nonwoven sheets enclosing the SAP-containing BNW. Adhesive beads can bond the first and second NW sheets between adjacent sections of the BNW, maintain a wavy shape in the first top NW sheet, and provide pivot points for folding the core. Furthermore, such adhesive beads provide structural strength to the core. The first and second NWs can be bonded using a grooved forming roller with air suction to give the top NW a wavy shape.

[0046] In some embodiments, the absorbent core comprises multiple absorbent core configurations, the upper core configuration being formed by encapsulated SAP-containing BNW, and the lower core configuration comprising a pulp-SAP layer encased in NW. The upper core configuration can provide a corrugated top surface to the absorbent core, and the lower core configuration can provide a planar bottom surface to the absorbent core. In some embodiments, the absorbent core has a gradient SAP distribution, with gradient-distributed large SAP particles present within the upper core configuration and SAP granules contained within the lower core configuration (e.g., mixed with pulp).

[0047] Some aspects of the disclosure of the present invention include an absorbent core. This core includes a first absorbent core configuration. The first absorbent core configuration includes a plurality of separated sections of a fibrous configuration having a fibrous structure. A first nonwoven sheet is positioned above the fibrous configuration. A second nonwoven sheet is positioned below the fibrous configuration. The first nonwoven sheet is bonded to the second nonwoven sheet at locations between adjacent sections of the plurality of separated sections of the fibrous configuration. The absorbent material is positioned between the first and second nonwoven sheets within the fibrous configuration. Some aspects of the disclosure of the present invention include a multilayer absorbent core comprising an upper absorbent structure comprising a bulky fibrous structure containing SAP and a lower absorbent structure comprising pulp or fluff and SAP granules.

[0048] Some embodiments specify a method for depositing SAP within a BNW. This method includes the steps of introducing SAP into the BNW with a forced airflow, depositing SAP into the BNW, and filtering the SAP through it. In some embodiments, the BNW is pulp-free or fluff-free (i.e., pulpless or fluffless). The SAP passes through the BNW fibers and is captured by the BNW fibers. The BNW filters SAP particles from the airflow, and the SAP is dispersed in the z direction within the BNW. This method may include the step of introducing adhesive from the bottom of the BNW to form a gradient deposit of adhesive within the BNW. This can be done before the SAP deposit to enhance the capture of the SAP. This method may include the step of heating the BNW before the SAP deposit to tackify the BNW, bulk up the BNW, or combine the two. In some embodiments, the heated SAP airflow provides the heat to tackify and / or bulk up the BNW. In certain embodiments, adhesive particles can be contained within the airflow. In some embodiments, the BNW is a multilayer BNW with gradient density, where the gradient distribution of SAP / adhesive has gradients in the x, y, and / or z directions. Different densities within the BNW can facilitate the formation of gradients in the SAP / adhesive distribution. In some such embodiments, the SAP addition is varied over time using induction valves, pulses, blinds, or other such methods to generate a y-gradient (MD) of SAP within the BNW.

[0049] Some embodiments relate to a method that includes the step of forming an absorbent core by encapsulating a plurality of absorbent sections filled with SAP between two nonwoven sheets. In some embodiments, an adhesive is pre-applied between the lower nonwoven fabric and the absorbent sections. A bead-like adhesive may be applied to coincide with the folds of the absorbent core. The upper cover layer of the two nonwoven sheets is fitted into the lower nonwoven sheet at the locations corresponding to the folds. In some such embodiments, a grooved forming roller with air suction is used to conform the upper cover layer of the two nonwoven sheets to its grooved surface to form a corrugated shape therein and to bond the upper and lower layers of the two nonwoven sheets.

[0050] Some embodiments specify a method comprising the steps of capturing SAP granules filtered through a BNW and guiding the captured SAP granules into a lower core structure. The captured SAP granules can be mixed into the fluff / air stream of a hammer mill used to form the pulp-SAP layer of the lower core structure.

[0051] Some aspects of the disclosure of the present invention include a method for capturing SAP within a fibrous structure. The method includes passing a forced airflow containing SAP through the fibrous structure. At least a portion of the SAP is deposited within the fibrous structure. The method includes filtering the SAP through the fibrous structure at least partially such that a gradient distribution of SAP particle size is formed within the fibrous structure.

[0052] Some embodiments of the disclosure of the present invention include an absorbent article comprising an absorbent core and a chassis comprising a back sheet and a top sheet according to the disclosure of the present invention. The absorbent core is positioned between the top sheet and the back sheet and bonded to the back sheet at selected locations and not bonded to the back sheet at other selected locations. Some aspects of the disclosure of the present invention include a disposable absorbent article comprising a chassis defining a front region and a waist region and a crotch region between them. The absorbent core composite is supported by the chassis and positioned at least partially in the crotch region. The core composite comprises a plurality of spaced-apart absorbent sections having area dimensions in the x and y directions and a thickness in the z direction. Each absorbent section has an absorbent structure comprising a fibrous material.

[0053] Some embodiments relate to a method that includes the step of mounting an absorbent core to a chassis such that the core is pre-folded / bundled. Such mounting allows the core to be pre-folded into a W-shape configuration, and an air channel can be formed between the chassis and the core.

[0054] Some aspects of the disclosure of the present invention include a method for making an absorbent core. The method includes the steps of transporting a fibrous structure, depositing SAP on the fibrous structure from a forced airflow, and filtering the SAP at least partially through the fibrous structure. The method then includes the steps of separating the fibrous structure into a plurality of separated sections and bonding a first nonwoven sheet below the sections of the fibrous structure. The method also includes the steps of positioning a second nonwoven sheet above the sections of the fibrous structure and bonding the second nonwoven sheet to the first nonwoven sheet at locations between adjacent separated sections of the fibrous structure.

[0055] Some aspects of the disclosure of the present invention include an apparatus for introducing SAP into a fibrous structure. The apparatus includes a fibrous structure conveyor, a forced airflow generator positioned to flow a forced airflow through the fibrous structure on the fibrous structure conveyor, and an SAP supply source positioned upstream of the fibrous structure conveyor to combine the SAP with the forced airflow.

[0056] Some embodiments of the disclosure of the present invention include a roller for forming a corrugated top sheet of an absorbent core. The roller includes a body, a roller surface, and grooves formed on the roller surface.

[0057] In one aspect of the disclosure of the present invention, the absorbent core composite comprises a plurality of spaced absorbent sections and features a plurality of pre-positioned folds between the absorbent sections. Furthermore, another embodiment of the absorbent composite or disposable absorbent article may include one or more of the following features: (1) a "W" shaped profile in the fitted worn configuration or the flat pre-worn configuration (of the disposable absorbent article); (2) absorbent wing sections having a width equal to 20% to 35% of the total width (TW) of the core, and in yet another variation, a width equal to 25% to 30% of TW or 30% ± 2.5% of TW; (3) a core fixed along a bond line coinciding with the outer fold of the core; (4) the bottom "surface" (e.g., bottom NW) of the absorbent core composite is planar, while the top layer or cover layer (body side) is corrugated and includes a step (preferably attached to the bottom layer) that drops into the bottom of each gap to enhance the clarity of the folds. (5) Four absorbent sections separated by three folds, while traversing the uppermost contour of the absorbent composite; (6) Three folds (and preferably two wing sections) including two fixed outer folds and a free central fold connecting a pair of intermediate sections; (7) Three folds including a free central fold that biases a pair of intermediate sections upward toward each other; (8) Separated absorbent sections each consisting of a fibrous structure that maintains the distribution of SAP particles; (9) Separated absorbent sections each including a structure that maintains the SAP particle distribution in the z direction and / or other distributions and SAP configurations described herein; and (10) Other features described below and / or depicted in one or more of Figures 1-20E or shown in Table 1.

[0058] The disclosure of the present invention also provides an absorbent core composite comprising an absorbent structure in which the distribution of SAP is maintained. In one embodiment, an absorbent structure is employed that features a fibrous structure in which the distribution of SAP is maintained. The application of this concept may include in an absorption structure or absorption section one of the following structural features or any combination thereof (each feature is further defined below): (1) a fibrous structure that maintains SAP distribution in the z direction; (2) SAP of different sizes positioned in different density zones of the fibrous structure; (3) use of bulky nonwoven or crepe spunbond as the fibrous structure; (4) a fibrous structure characterized by SAP properties that vary based on the expected position; (5) use of adhesive gradients in the fibrous structure; (6) SAP / adhesive gradients; (7) multidensity layer BNW; (8) preheated BBNW; (9) two-component BNW fibers including a high-melting-point core and a low-melting-point shell such that the shell softens before the core to provide an adhesive surface for capturing SAP; (10) a bottom surface activated (e.g., by IR) to enhance activation at the bottom / enhance the adhesive effect at the bottom; (11) a reactivated BNW (e.g., by heat, IR, or hot SAP); and (12) crepe spunbond.

[0059] Absorbent articles The concepts disclosed herein can be applied to absorbent articles such as the infant diaper 10 depicted in Figures 1-3, which incorporates an absorbent composite or absorbent core 46 to receive and store excrement. The diaper 10 comprises an upper sheet 50, a lower sheet 60, and an absorbent core 46. The diaper 10 further includes an upright barrier cuff 34 that extends longitudinally along the diaper and stretches to conform to the wearer's buttocks. The diaper further includes an elastic band 52 and fastening elements 26. The elements 26 extend to and engage with the corresponding opposing ends of the diaper during use, securing the diaper to the wearer. The web structure shown in Figure 2 can subsequently be trimmed, folded, sealed, welded, and / or otherwise operated to form the finished or final form of the disposable diaper 10. To facilitate the description of the diaper 10, the description refers to a longitudinal axis AA, a transverse central axis BB, a pair of longitudinal side edges 90, and a pair of end edges 92 extending between the side edges 90. Along the longitudinal axis AA, the diaper 10 includes a first end region or front waist region 12, a second end region or rear waist region 14, and a crotch region 16 positioned between them. Each of the front and rear waist regions 12, 14 is located on either side of the central body portion 20 and features a pair of ear regions or ears 18 extending transversely from the side edges 90. Fastening elements 26 (e.g., conventional tape fasteners) are fastened to each of the ears 18 along the rear waist region 14 of the diaper 10. When the diaper 10 is worn around the waist, the front waist region 12 fits adjacent to the wearer's front waist, the rear waist region 14 fits adjacent to the rear waist, and the crotch region 16 fits around and below the crotch area. To properly secure the diaper 10 to the wearer, the ears 18 of the rear waist region 14 are provided to align with the ears 18 of the front waist region 12, with the wearer's waist facing forward. The fastening surface may be provided on or by the inner or outer surface of the front waist region 12. Alternatively, a fastening element 26 can be positioned on the ears 18 of the front waist region 12 and fastened to the ears 18 of the rear waist region 14. A suitable diaper structure typically uses at least three layers. These three layers include a backing sheet 60, an absorbent core 46, and a top sheet 50.The diaper structure may or may not include a pair of containment walls or leg cuffs 34 positioned upward from the top sheet 50, and preferably includes at least one or more spaced longitudinally stretchable members 38. It is shown below that any of these diaper elements or combinations thereof can be manufactured using or using any of the absorbent core composites disclosed herein. Furthermore, an acquisition layer 48 can be added to improve performance. The core 46 can be any of the absorbent cores disclosed herein.

[0060] Absorbent core composite Figure 4A is a perspective view of the absorbent core composite 100 in a flat, stretched configuration, i.e., before wear. Figure 5 is a detailed cross-sectional view of the absorbent composite of Figure 4A along line CC. In one aspect of the disclosure of the present invention, the absorbent composite 100 comprises an upper absorbent layer or upper absorbent structure 102 as a primary central core configuration and a lower absorbent layer or lower absorbent structure 104 providing a secondary absorbent core configuration. Although the absorbent core 100 is shown to include upper and lower core components, in some applications it may consist only of the upper absorbent structure 102.

[0061] Absorbent core composite - fibrous structure The upper absorption structure 102 includes fibrous structures 106a to 106d. In some embodiments, the fibrous structures 106a to 106d preferably include nonwoven fabric, specifically bulky nonwoven fabric or crepe spunbond. In some embodiments, the fibrous structures 106a to 106d are or include air-bonded nonwoven fabric manufactured using crimped two-component fibers of PET / PP (PP core with PET sheath) or PP / PE (PP core with PE sheath).

[0062] As shown in the figure, the upper absorbing structure 102 preferably includes four spaced sections of fibrous configuration 106a to 106d. As will be further described below, a main core composite divided into four spaced sections, including two outer wing sections wider than two central sections, provides a particularly advantageous absorbing structure. However, the upper absorbing structure 102 is not limited to four separate spaced sections with respect to the fibrous configuration, but may include other numbers of fibrous configurations. For example, the upper absorbing core 102 may include 2 to 10 separate spaced sections with respect to the fibrous configuration. In some embodiments, the upper absorbing structure 102 does not include multiple separate spaced sections with respect to the fibrous configuration, but rather includes only a single continuous fibrous configuration.

[0063] Each section of the fibrous structure 106a to 106d extends longitudinally along the length of the absorbent core 100 between the anterior and posterior waist regions. In some embodiments, each section of the fibrous structure 106a to 106d extends continuously from the first longitudinal edge 112a to the second longitudinal edge 112b of the absorbent core 100.

[0064] The fibrous structures 106a to 106d preferably contain and retain an absorbent material (not shown), such as a superabsorbent polymer (SAP). The absorbent material can be incorporated within the fibrous structure of the fibrous structures 106a to 106d (e.g., entangled with the fibers). In some embodiments, the size, absorbent properties, and quantity (e.g., weight and / or number of absorbent particles) can be varied in the x, y, z directions, or a combination thereof, as will be described in more detail below. In some embodiments, each fibrous structure 106a to 106d is a bulky nonwoven fabric impregnated with SAP.

[0065] Absorbent core composite - channel The gaps or channels 114a to 114c are positioned between adjacent sections of the fibrous structures 106a to 106d. Channels 114a to 114c can each be separate, spaced-out channels positioned between two fibrous structures. Although shown as including three separation channels, the upper absorbing structure 102 is not limited to three separate spaced-out channels and can include any other number of channels. For example, the upper absorbing structure 102 can include 1 to 9 separate spaced-out channels. In some embodiments, the upper absorbing structure 102 does not include such channels, such as when the upper absorbing structure 102 includes only a single continuous fibrous section.

[0066] Channels 114a to 114c are at least partially defined by the nonwoven sheet configuration of the upper absorption structure 102. As shown in Figure 5, the upper absorption structure 102 includes an upper nonwoven sheet 116 and an intermediate nonwoven sheet 118. Although shown as including two separate nonwoven sheets 116 and 118, the upper absorption structure 102 can include a different number of nonwoven sheets, for example, a single nonwoven sheet that is wrapped around or folded around the fibrous structures 106a to 106d and positioned both above the fibrous structures 106a to 106d (i.e., where the upper nonwoven sheet 116 is shown) and below the fibrous structures 106a to 106d (i.e., where the intermediate nonwoven sheet 118 is shown).

[0067] Channels 114a-114c can extend longitudinally along the core 100, parallel to the longitudinal centerline 110. In some embodiments, at least one of channels 114a-114c (e.g., channel 114b) extends coincidentally with the longitudinal centerline 110. Channels 114a-114c can be or define absorbent material-free lines, strips, sections, or grooves in the absorbent core 100 (i.e., channels 114a-114c can be substantially empty spaces for absorbent material). During use, channels 114a-114c can function to facilitate fluid flow along the longitudinal length of the absorbent core 100 (i.e., between edges 112a and 112b) and enhance fluid distribution throughout the absorbent core 100. Such enhanced longitudinal fluid flow can increase the utilization of the absorbent core 100, as fluid can approach more parts of the absorbent core 100, such as during urination. Therefore, channels 114a to 114c can improve the surface drying properties of the absorbent core 100 and / or the absorbent article containing the absorbent core 100, thereby reducing the possibility of leakage and enabling the absorbent core 100 to be used for a longer period of time.

[0068] In one exemplary embodiment, the total width of the absorbent core 100 is 100 mm, the width of each fiber section 106a and 106d positioned laterally on the outside is 20 mm, the width of each fiber section 106b and 106c positioned in the center on the inside is 15 mm, and the width of the space between each adjacent fiber section 106a-106d is approximately 5 mm or 6 mm. Since the absorbent core and its components may have other dimensions, these dimensions are, of course, merely illustrative for one particular core. In some embodiments, the total width of the absorbent core is 60–130 mm, or 70–110 mm, or 80–100 mm; the width of each fiber section positioned laterally on the outside is 15–30 mm, or 18–25 mm, or about 20 mm; the width of each fiber section positioned centrally on the inside is 7–20 mm, or 10–18 mm, or 13–16 mm, or about 15 mm; and the width of the space between each adjacent fiber section is 2–10 mm, or 3–8 mm, or 4–7 mm, or 5–6 mm, or a combination thereof.

[0069] The fiber sections 106a to 106d can be bonded to the lower intermediate nonwoven sheet 118. For example, the fiber sections 106a to 106d can be bonded to the intermediate nonwoven sheet 118 through adhesives 120a to 120d. Although shown as the fiber sections 106a to 106d being bonded to the intermediate nonwoven sheet 118, in some embodiments the fiber sections 106a to 106d are not bonded to the intermediate nonwoven sheet 118. In some embodiments the adhesives 120a to 120d are or include hot melt adhesives (HMA). In some embodiments the width of each application of adhesive 120a to 120d is smaller (i.e., narrower) than the width of each fiber section 106a to 106d. Adhesives 120a to 120d, such as HMA, can be applied to the fiber sections 106a to 106d, the intermediate nonwoven sheet 118, or both by slotting or spray application.

[0070] The upper nonwoven sheet 116 is positioned on the opposite side of the intermediate nonwoven sheet 118, above the fiber sections 106a-106d. The upper nonwoven sheet 116 is bonded to the intermediate nonwoven sheet 118. For example, the upper nonwoven sheet 116 can be bonded to the intermediate nonwoven sheet 118 through adhesive beads 122a-122e. The adhesive beads 122a-122e can be in the form of linear strips or tubes. The adhesive beads 122a-122e can extend continuously or intermittently from edge 112a to edge 112b. The adhesive beads 122a-122e provide a seal between the upper nonwoven sheet 116 and the intermediate nonwoven sheet 118, where the fiber sections 106a-106d can be enclosed. In some embodiments, each adhesive bead 122a-122e is in the form of a line or ball of hot melt adhesive. Adhesive beads 122a to 122e can have a unit weight of approximately 10 g / m (grams per meter of wire length) or 8 to 12 g / m.

[0071] The space between the upper nonwoven sheet 116, the intermediate nonwoven sheet 118, and the adhesive beads 122a-122e defines tubes 124a-124d that extend longitudinally from edge 112a to edge 112b, parallel to the longitudinal centerline 110. Each fiber section 106a-106d is enclosed and maintained within a separate tube 124a-124d. The adhesive beads 122a-122e can be made strong enough so that when soiled, the absorbent material enclosed in the fiber sections 106a-106d is maintained within its fiber structure or at least within each respective tube 124a or 124d.

[0072] The upper nonwoven sheet 116 is bonded to the lower nonwoven sheet 118 at the location between the lower nonwoven sheet 118 and the uppermost surfaces 1107 of the fiber sections 106a-106d, so that the upper nonwoven sheet 116 is bonded to the intermediate nonwoven sheet 118 by extending at least partially into the space between the fiber sections 106a-106d, forming a contour around them. Such contouring of the upper nonwoven sheet 116 around and between the fiber sections 106a-106d defines at least partially the channels 114a-114c. In some embodiments, the upper nonwoven sheet 116 provides a corrugated upper surface to the absorbent core 100. In some embodiments, the intermediate nonwoven sheet 118 provides a flat lower surface to the upper absorbent structure 102. The upper nonwoven sheet 116 may be corrugated and the intermediate nonwoven sheet 118 may be flat, but the upper nonwoven sheet 116 and the intermediate nonwoven sheet 118 may have the same footprint. That is, the intermediate nonwoven sheet 118 may be substantially flat and the upper nonwoven sheet 116 may be substantially corrugated, so the area of ​​the upper nonwoven sheet 116, when defined over the lateral range of the core 100, is at least 120%, or at least 130%, or at least 140%, or at least 150%, or at least 175%, or 120% to 175%, or 130% to 150%, of the area of ​​the intermediate nonwoven sheet 118 over the same lateral range of the core 100.

[0073] Absorbent core composite - fold In some embodiments, the contouring of such upper nonwoven sheet 116 around and between the fiber sections 106a-106d, together with the adhesive beads 122a-122e and channels 114a-114c, at least partially defines the folds of the absorbent core 100. The folds 126a-126c can coincide with channels 114a-114c, as shown in Figure 4A. The folds 126a-126c facilitate the folding of the absorbent core 100 from a flat configuration, as shown in Figure 4A, to a folded and / or bundled configuration (e.g., a W-shaped configuration), as described in detail below in relation to Figures 8-9D. In some embodiments, each fold 126a-126c extends parallel to the longitudinal centerline 110 of the core 100. In some embodiments, at least one of the folds 126a to 126c (e.g., fold 126b) coincides with the longitudinal centerline 110 of the core 100.

[0074] Although described as "folding," as used herein, "folding" does not require a 180° pivot rotation of the fiber sections 106a-106d around the folds 126a-126c, nor does it require adjacent fiber sections 106a-106d that are folded toward each other to be in contact. Rather, as used herein, "folding" involves pivoting adjacent sections of the fibrous configuration 106a-106d to reduce the angle between the two adjacent sections. For example, as shown in Figure 4A, when the core 100 is in a flat configuration, the adjacent sections of the fibrous configuration 106a-106d are at a flat angle (i.e., 180°) relative to each other. When in a folded and / or bundled configuration (e.g., W-shaped), adjacent sections of the fibrous configuration 106a-106d are at angles to each other that are less than 180° but greater than 0°, or 160°-20°, or 140°-40°, or 120°-60°, or 100°-80°.

[0075] The upper nonwoven sheet 116 and the lower nonwoven sheet 118 can function to enclose the fiber sections 106a-106d between them, surrounding the fiber sections 106a-106d and facilitating the prevention of superabsorbent particles (or other absorbent materials) from moving out of the respective nonwovens or tubes 124a-124d in which they are confined. The upper nonwoven sheet 116 and the lower nonwoven sheet 118 may be any nonwoven fabric disclosed herein or known to those skilled in the art, non-limited to spunbond-meltblown-spunbond (SMS) nonwovens and spunbond nonwovens made from synthetic or natural fibers.

[0076] Absorbent core composite - pulp layer The absorbent core 100 includes a lower absorbent structure 104, which is positioned below and adjacent to the upper absorbent structure 102. The lower absorbent structure 104 is coupled to the upper absorbent structure 102. In some embodiments, the lower absorbent structure 104 is bonded to the upper absorbent structure 102 through an adhesive 128 or the like. The adhesive 128 can be, for example, a hot melt adhesive.

[0077] The lower absorbing structure 104 may be or include a lower fibrous structure 130, which may be a fluff and / or pulp fibrous absorbing structure that provides additional absorption capacity to the absorbent core 100. In some embodiments, the lower fibrous structure 130 may include synthetic fibers, natural fibers, or a combination thereof. For example, the lower fibrous structure 130 may be or include aggregates and / or networks of pulp fibers such as cellulose fibers, including but not limited to microfibrillated cellulose (MFC) fibers, nanofibrillated cellulose (NFC) fibers, or a combination thereof. The lower fibrous structure 130 may include cellulose fibers such as fluff pulp formed by a conventional fluff pulp core formation process. Alternatively, the cellulose fibers of the lower fibrous structure 130 may be formed by an air-deposited web. The lower fibrous structure 130 may include synthetic fibers that can be formed as a permeable bonded web, such as a permeable bonded web of polyethylene terephthalate / polyethylene / polypropylene (PET / PE / PP) fibers. In other embodiments, the lower fibrous structure 130 may include foam, bulky nonwoven fabric, permeable nonwoven fabric, pulp, absorbent material, or any combination thereof.

[0078] In some embodiments, the lower fibrous structure 130 includes an absorbent material (not shown) such as SAP mixed with its pulp fibers. In certain embodiments, a gradient distribution of absorbent material particles (e.g., SAP particles) exists throughout the absorbent core 100. For example, relatively large absorbent material particles may be trapped in the fiber sections 106a-106d, while relatively small absorbent material particles may be trapped in the lower fibrous structure 130. As described in more detail elsewhere in this specification, the fiber sections 106a-106d may include a gradient distribution of absorbent material particles in the z direction such that relatively large absorbent material particles are distributed on or near the uppermost surface 1107 of the fiber sections 106a-106d, while relatively small absorbent material particles are distributed on or near the bottom surface 109 of the fiber sections 106a-106d. The lower fibrous structure 130 may include absorbent material particles smaller than those distributed on or near the bottom surface 109 of the fiber sections 106a-106d. For example, the lower fibrous structure 130 can contain absorbent material particles "fine grains," while the fibrous sections 106a to 106d can contain absorbent material particles larger than "fine grains." In some embodiments, the fibrous sections 106a to 106d do not have a gradient distribution of absorbent material particles in the z direction.

[0079] In some embodiments, the basis weight of the lower fibrous structure 130 (e.g., cellulose pulp fibers) is relatively low, for example, about 40 gsm. The lower fibrous structure 130 is not limited to such a basis weight and can have a lower or higher basis weight. However, in some embodiments, it is preferable to minimize the basis weight of the lower fibrous structure 130 for reasons such as cost reduction.

[0080] The lower absorbent structure 104 includes one or more nonwoven sheets positioned on at least one side thereof. As shown in Figure 5, the lower absorbent structure 104 includes a nonwoven sheet 132 positioned around the lower fibrous structure 130 in a C-wrap configuration. The nonwoven sheet 132 is or may include any of the nonwoven fabrics disclosed herein, including but not limited to SMS nonwoven fabric, spunbond nonwoven fabric, or tissue.

[0081] The nonwoven sheet 132 is bonded to the lower fibrous structure 130. For example, the nonwoven sheet 132 can be bonded to the lower fibrous structure 130 through adhesives 134a and 134b, the adhesives of which may be hot-melt adhesives applied to the upper and / or lower surfaces of the lower absorbent structure 130 (as shown in the figure). Adhesive 134b positioned on the bottom surface of the lower fibrous structure 130 can function to attach the nonwoven sheet 132 to the lower fibrous structure 130. Adhesive 134b may be a hot-melt adhesive applied by any method commonly used in the manufacture of absorbent articles and composites, including spray application, slot application, or controlled application methods. Adhesive 134a positioned on the uppermost surface of the lower fibrous structure 130 can function to bond the lower absorbent structure 104 to the upper absorbent structure 102, such as an intermediate nonwoven sheet 118. Adhesive 134a can also function to enhance its dry and wet integrity by holding the fibers and / or absorbent material of the lower absorbent structure 104 in place during manufacturing, transport, and / or use. Adhesives 134a and 134b can constitute any suitable formulation of hot melt adhesives, including but not limited to construction adhesives and core-integrating adhesives, depending on the specific function the adhesive is intended to perform.

[0082] With the nonwoven sheet 132 positioned around the lower fibrous structure 130 in a C-wrap configuration, it provides an opening 136 for receiving fluid flow from the upper absorbent structure 102 into the lower absorbent structure 104. In another embodiment, the nonwoven sheet 132 is positioned on only one side of the lower fibrous structure 130. In yet another embodiment, the nonwoven sheet 132 completely surrounds the lower fibrous structure 130 on all sides. Although shown as including a single nonwoven sheet 132, the lower absorbent structure 104 may include multiple nonwoven sheets or webs positioned on and / or around the lower fibrous structure 130 to completely or partially surround it. The nonwoven sheet 132 can function to surround the fibers, absorbent material, or combination thereof of the lower absorbent structure 130, thereby ensuring the structural and positional integrity (dry and wet integrity) of the lower fibrous structure 130 during the manufacture, transport, and use of the absorbent core 100.

[0083] In some embodiments, the lower fibrous structure 130 (also called the pulp layer) is a relatively low-basis-weight pulp layer positioned at the bottom of the core 100. The lower fibrous structure 130 can provide the user with a soft feel against the outer cover. The lower fibrous structure 130 can also impart at least some absorbency and suction properties to the core 100. The lower fibrous structure 130 can increase fluid suction toward the front and rear ends of the core 100 and provide a temporary reservoir for fluids not absorbed by the SAP. In some embodiments, the lower fibrous structure 130 is combined with or replaced by an air-deposited nonwoven fabric (e.g., cellulose air-deposited nonwoven fabric). In some embodiments, the lower fibrous structure 130 provides a structural layer positioned below the fibrous sections 106a-106d.

[0084] Figure 4B is a detailed view of the core of Figure 4A, showing its layers. In some embodiments, as shown in Figure 4B, an additional intermediate nonwoven fabric layer 119 can be provided between the intermediate nonwoven sheet 118 and the nonwoven sheet 132. The additional intermediate nonwoven fabric layer 119 can be bonded to the intermediate nonwoven sheet 118 through an adhesive 121 or the like. The additional intermediate nonwoven fabric layer 119 can form part of the upper absorption structure, or part of the lower absorption structure, or it can be a separate structure positioned between the upper and lower absorption structures.

[0085] Absorbent article having an absorbent core Figures 6 and 7 show an absorbent core incorporated into an absorbent article such as a diaper, which is the same as or substantially similar to that in Figure 5. In some embodiments, a structural layer or component (e.g., a chassis or part thereof) is positioned below the core 100. The structural layer can be fixed to the lateral margin of the core 100. The absorbent article 200 includes a backing sheet 202, which can be a liquid-impermeable sheet. The backing sheet 202 is bonded to the underside of the absorbent core 100. As shown, the backing sheet 202 is bonded (e.g., glued) to the nonwoven sheet 132 of the lower absorbent structure 104. However, if the absorbent core 100 does not include the lower absorbent structure 104, the backing sheet 202 can be bonded (e.g., glued) to the intermediate nonwoven sheet 118 of the upper absorbent structure 102. The backing sheet 202 is bonded to the nonwoven sheet 132 through an adhesive 204, which can be a hot-melt adhesive. The backing sheet 202 can be any backing sheet used for absorbent articles known to those skilled in the art.

[0086] The absorbent article 200 includes a top sheet 206, which may be a liquid-impermeable sheet. The top sheet 206 is bonded to the upper absorbent structure 102 of the absorbent core 100. As shown in the figure, the top sheet 206 is bonded to the upper absorbent structure 102 through an adhesive 208. The adhesive 208, which may be a hot-melt adhesive, bonds the top sheet 206 to a portion of the upper nonwoven sheet 116. The top sheet 206 may be any top sheet used in absorbent articles known to those skilled in the art.

[0087] The absorbent article 200 includes an acquisition and distribution layer, ADL210, positioned between the top sheet 206 and the absorbent core 100. The ADL210 can function to receive waste from the top sheet 206 and distribute the waste to the absorbent core 100. The ADL210 can be any acquisition and distribution layer known to those skilled in the art. The ADL210 can be bonded to the top sheet 206 through a portion of the adhesive 208. Similarly, the ADL210 can be bonded (e.g., adhered) to the absorbent core 100 through adhesives 212a-212d (e.g., hot melt adhesives). For example, adhesives 212a-212d can be positioned on the upper nonwoven sheet 116 above tubes 124a-124d, respectively, and bonded to the ADL210. Although shown as including the ADL210, the absorbent articles disclosed herein are not limited to including an acquisition and distribution layer.

[0088] A portion of the top sheet 206 can also be bonded to the back sheet 202 through a portion of the adhesive 204, etc. Therefore, since the top sheet 206 and the back sheet 202 surround the absorbent core 100, the absorbent core 100 is trapped within the top sheet 206 and the back sheet 202 (for example, sandwiched between them).

[0089] W-shaped absorbent core In some embodiments, the disclosure of the present invention includes an absorbent core composite having absorbent sections that are spaced apart and pivotable to each other. Referring to Figure 8, one such exemplary absorbent core 100 is depicted. The absorbent core 100 in Figure 8 may be the same as or substantially the same as the absorbent core 100 shown in Figure 4A, whereas in Figure 8 the absorbent core 100 is shown in a pivoted or bundled configuration, whereas in Figure 4A the absorbent core 100 is shown in a flat configuration. The flat configuration of the absorbent core 100 as shown in Figure 4A may be the configuration of the absorbent core 100 during the manufacture of the absorbent article, during the packaging and transport of the absorbent core 100, and / or at any point before the use of the absorbent core 100.

[0090] When an absorbent core 100 incorporated within an absorbent article is worn by a user, the force applied to the absorbent core 100 from the user's body may cause the absorbent core 100 to bunch and / or fold. Folds 126a to 126c positioned between adjacent, spaced-apart, and mutually pivotable absorbent sections (fiber sections 106a to 106d) of the absorbent core 100 achieve or facilitate controlled bunching of the absorbent core 100. The folds 126a to 126c define the pivot axis from which the sections of the fiber sections 106a to 106d pivot while the absorbent core 100 folds into a W-shape or other accordion-shaped configuration. For example, with the absorbent core 100 positioned between the user's thighs, the user's thighs may exert forces on the absorbent core 100 having force components directed parallel to the transverse centerline 108 of the absorbent core 100, force components directed in the Z direction, or a combination thereof. Such forces may result in folding and / or bunching of the absorbent core 100, particularly around or along folds 126a-126c in the central crotch region 111 of the absorbent core 100. Since such bunching and / or folding of the absorbent core 100 may be limited to or at least concentrated in the central crotch region 111, the side edges 113a and 113b of the core 100 are provided with curved segments 138 in the central crotch region 111. Thus, when worn, the absorbent core 100 may have an hourglass shape or substantially an hourglass shape as a result of folding and / or bunching, rather than as a result of cutting. The core 100 takes on a W-shape when worn between the user's legs, and therefore narrows laterally in the central groin area 111 between the legs, similar to a core cut into an hourglass shape. However, the core 100 does not exhibit the absorption loss obtained in an hourglass shape, which would result from cutting the core and removing the absorbent material therefrom in order to achieve the hourglass shape.

[0091] Such assembling and / or folding of the absorbent core 100 can provide the absorbent core 100 with an accordion-shaped configuration. In some such embodiments, such assembling and / or folding of the absorbent core 100 can provide the absorbent core 100 with a W-shaped configuration or a substantially W-shaped configuration, as shown in Figures 8-9H. The specific shape that the core 100 is urged to take when worn may vary, for example, depending on the number of folds 126, the spacing between folds 126, the width of folds 126, the spacing between fiber sections 106, the width of fiber sections 106, and the number of fiber sections 106. The absorbent core 100 is not limited to folding into a W-shaped configuration and can be folded and / or assembled into other accordion shapes.

[0092] Referring to Figures 8 and 9A, when the absorbent core 100 is forced into a W-shaped configuration, the force applied to the core 100 creates a moment around the folds 126a to 126c, causing adjacent fiber sections 106 to pivot around the fold 126 between them, prompting the core 100 upward in the Z direction at fold 126b and edges 113a and 113b, and prompting the core 100 to fold itself around the fold 126. In the W-shaped configuration, the folds 126a and 126c are positioned closer to each other in the Y direction compared to the relative positions of the folds 126a and 126c when the core 100 is in a flat configuration (as shown in Figure 4A). Similarly, in the W-shaped configuration, the edges 113a and 113b are positioned closer to each other in the Y-direction compared to the relative positions of the edges 113a and 113b when the core 100 is in a planar configuration (as shown in Figure 4A). Furthermore, the fold 126b and the edges 113a and 113b are higher in the Z-direction compared to the positions of the folds 126a and 126c. As shown in the figure, the edges 113a and 113b are positioned at a raised height 142 above the folds 126a and 126c. In the W-shaped configuration, the core 100 includes a valley 140 defined between the peak 150 and the raised side edges 113a and 113b. With the edges 113a and 113b at the raised height 142, the fluid trapped in the valley 140 must flow upward against gravity in order to flow outside the core 100. Therefore, the raised lateral edges 113a and 113b reduce or eliminate the occurrence of fluid leakage (or other leaks) from the core 100. Thus, the W-shaped core 100 reduces lateral, transverse fluid flow toward the side edges 113a and 113b of the core 100, thereby reducing the possibility of the absorbent product leaking from its side edges.

[0093] Referring to Figure 9B, the absorbent core 100 is shown bonded to the backing sheet 202. The absorbent core 100 is bonded to the backing sheet 202 or otherwise bonded at attachment points 300 (e.g., bond lines or sections). The attachment points 300 are positioned below the folds 126a and 126c. The lateral distance 302 between the attachment points 300 is smaller than the lateral distance between the folds 126a and 126c when the core 100 is in a flat configuration (e.g., as shown in Figure 4A). Therefore, when the core 100 is bonded to the backing sheet 202 through the attachment points 300, the folds 126a and 126c are brought closer to each other in the y-direction (lateral direction) than when the core 100 is in a flat configuration, so that the attachment of the core 100 to the backing sheet 202 pre-folds the core 100 into a W-shaped configuration, at least partially.

[0094] As is evident from Figure 9B, in some embodiments, folding the core 100 into a W-shape results in the formation of a channel 310 positioned between the core 100 and the backing sheet 202. The channel 310 functions as an airflow channel between the core 100 and the backing sheet 202, promoting the drying of the core 100 and making the wear of the absorbent article more comfortable. Figure 9C shows the expected exemplary relative positional arrangement of the backing sheet 202 and the core 100, along with the expected exemplary relative positional arrangement of the fiber sections 106a-106d of the core 100, along with the expected exemplary relative positional arrangement of the backing sheet 202 and the core 100 when the absorbent article containing the core 100 is worn by a user and force is applied to it from the user's thigh. As shown, the backing sheet 202 acts upward along the z-direction due to the force applied to it from the user's thigh. Such forces are also transmitted to the core 100, facilitating its folding into a W-shape configuration, causing the fiber sections 106a-106d to pivot around the folds 126a-126c, lifting the edges 113a and 113b of the core 100 to a raised height 142 above the back sheet 202.

[0095] In some embodiments, as shown in Figure 9C, the core 100 is not bonded or otherwise attached to the backing sheet 202 at any point between edge 113a and fold 126a or between edge 113b and fold 126c at edges 113a and 113b. Thus, the fiber sections 106a and 106d and edges 113a and 113b can move freely relative to the backing sheet 202 and move freely above the backing sheet 202. The movement of the fiber sections 106a and 106d and edges 113a and 113b is still restrained by attaching the core 100 to the backing sheet 202 at the attachment point 300. Similarly, in some embodiments, the core 100 is not bonded to or otherwise attached to the backing sheet 202 between the mounting portions 300, so that the fiber sections 106b and 106c can move freely relative to the backing sheet 202 and move freely upward above the backing sheet 202 to form the channel 310. The movement of the fiber sections 106b and 106c is still restrained by attaching the core 100 to the backing sheet 202 at the mounting portions 300.

[0096] Figure 9D shows another embodiment of the core 100 bonded to the backing sheet 202 in a W-shaped configuration. In Figure 9D, the core 100 is attached to the backing sheet 202 continuously or substantially continuously through an adhesive 301 or the like. Thus, if a portion of the core 100 is forced into a W-shaped configuration, the portions of the backing sheet 202 attached to each portion of the core 100 are also forced into a W-shaped configuration as shown. When the backing sheet 202 is attached to the core 100 continuously or substantially continuously, no channel 310 (Figure 9C) is formed between them. Similarly, since the edges 113a and 113b are bonded to the backing sheet 202, they cannot rise above the backing sheet 202 to a rise height, but even in the W-shaped configuration, they are still at a rise height relative to the folds 126a and 126c.

[0097] During use, the folds 126a to 126c of the core 100 allow the core 100 to dynamically respond to the dynamically changing forces applied to it when the user wears it. For example, when the user walks, the force applied to the core 100 varies according to the movement of the user's legs. The folds 126a to 126c allow the core 100 to dynamically fold at least partially and unfold at least partially in response to the fluctuations of the forces applied thereto. Figure 9E shows some of the forces applied to the core 100 during use, as represented by the lines of force (arrows). Figure 9F shows the “wing section” 905 of the absorbent core. The wing section 905 is fixed at the “fixed fold” 907 but can move freely relative to the fixed fold 907 as a result of the “unfixed raised edge” 901. Similarly, a centrally located "unfixed raised central fold" 903 allows the central portion of the absorbent core to move relative to a fixed fold 907, forming an air channel 909. By selecting which folds are fixed and which are free relative to the underlying chassis (not shown for clarity), an absorbent core can be designed to fold in a predetermined manner. As shown in the figure, the absorbent core of Figure 9E is designed to fold into a W-shape. In this specification, unless otherwise specified, when one component is "free" from another component (e.g., an absorbent core free from the backing sheet), this means that the movement of the free component relative to that other component is not restricted by the free component at the indicated position. For example, an absorbent core free from the backing sheet along a particular fold can move freely relative to the backing sheet, at least along that fold, without being constrained.

[0098] In some embodiments, the fiber sections 106a–106d are four relatively stiff fiber sections with three folds between adjacent fiber sections 106a–106d. The stiffness of the fiber network of sections 106a–106d provides structural integrity to each section 106a–106d, facilitating its folding relative to other such sections without deformation or substantial deformation of the section. In some embodiments, the depth (gap between sections) of channels 114a–114c, together with the width of channels 114a–114c, provides pivot points around which sections 106a–106d can fold to enter a W-shaped configuration. The attachment of the upper nonwoven sheet 116 to the intermediate nonwoven sheet 118 defines, at least partially, such pivot points at the bottom of channels 114a–114c. Similarly, when incorporated into an absorbent article, the absorbent core can be folded, with the central fold free from the chassis and the side edges free from the chassis, so that the absorbent core is fixed to its chassis by bonding lines, the free portion of the absorbent core lifts up above the chassis, and the bonded section is fixed to the chassis. In some such embodiments, the absorbent core folds into a W-shape, so that the four fibrous structural sections have three relatively wide channels positioned between adjacent sections.

[0099] The fiber network of the upper absorption structure 102 holds the SAP deposited inside, and the SAP absorbs fluid, reducing the wet load on the fiber network, thereby allowing the fiber network and the upper absorption structure 102 to maintain structural integrity (wet and dry). Because structural integrity is maintained, the upper absorption structure 102 can maintain its folded (e.g., W-shaped) configuration in both wet and dry conditions.

[0100] Figures 9G and 9H show exemplary absorbent cores incorporated into absorbent articles and worn by a user. As shown in Figure 9G, the top sheet 206 can be fitted to the absorbent core 100 by bonding the top sheet 206 to the bottom surface of the absorbent core 100, so that the core 100 is wrapped or enclosed by the top sheet 206. The top sheet 206 can be folded under the core 100 and bonded to it. The top sheet 206 can be bonded (e.g., bonded) to the back sheet 202 at the attachment area 993 to maintain the encapsulation of the core 100 by the top sheet 206. Alternatively, as shown in Figure 9H, the top sheet 206 can be free from the absorbent core 100 (e.g., not bonded to the bottom surface of the absorbent core 100 and not folded under it), so that a space 997 is formed between the top sheet 206 and the core 100 and the back sheet 202. Also shown are the position and arrangement of the leg cuff 999 relative to the top sheet 206, the back sheet 202, and the core 100, as well as the leg gather 995. The leg cuff 999 and leg gather 995 enhance the fit of the absorbent material to the user's thigh 991 and prevent leakage. The absorbent core 100 is positioned in the center of the crotch area 989. When worn, the free portion of the core 100, i.e., the portion not adhered to the back sheet 202 at the attachment site 300, acts upward toward the user's crotch, forming a W-shaped core.

[0101] Fibrous structure with gradient SAP and adhesive distribution In some embodiments, the absorbent cores disclosed herein exhibit a gradient distribution of SAP or other absorbent material, an adhesive gradient distribution, or a combination thereof. Referring to Figure 10A, a portion of an exemplary core 100 is shown, including a fibrous structure 106 adjacent to a lower fibrous structure 130. For simplicity, not all components or layers of the core 100 are necessarily shown in Figure 10A, so only portions of the fibrous structure 106 and the lower fibrous structure 130 are shown.

[0102] In Figure 10A, the fibrous structure 106 is shown as a multilayer fibrous structure including three layers 107a to 107c. However, the fibrous structures disclosed herein are not limited to including three layers and may include any number of layers, including single layers or multilayer structures other than three layers (e.g., two or four layers). Layers 107a to 107c may be different sections of a single fibrous structure having different properties and may be multiple sublayers laminated together to form the fibrous structure 106.

[0103] In some embodiments, the fibrous structure 106 having layers 107a-107c is a single structure in which the density gradually changes from one side to the other. Such a structure can be made using a three-step process, in which component fibers are deposited and layers are stacked one by one using three different sequential carding operations to form a web. Each carding operation can provide different types and / or amounts of fibers. The result is a single structure having three different density layers. In some embodiments, the material has only one density (no gradient density), in which case the gradient density is generated by bulking or thermal expansion on one side, which reduces the density on one side.

[0104] As shown in the figure, the core 100 exhibits a gradient distribution of the absorbent material, in this case SAP400a~400d, in the z direction (i.e., from the upper surface 404 of the core 100 to the lower surface 406 of the core 100). In Figure 10A, SAP400a~400d has a gradient with respect to particle size, with the largest particle size SAP400a being positioned and held in the upper layer 107a of the fibrous structure 106. SAP400b, which has a smaller particle size than SAP400a, is positioned and held in the intermediate layer 107b of the fibrous structure 106. SAP400c, which has a smaller particle size than SAP400b, is positioned and held in the lower layer 107b of the fibrous structure 106. SAP400d, which has a smaller particle size than SAP400c, is positioned and held in the pulp layer of the lower fibrous structure 130. The gradient of SAP400a~400d is shown and explained as a gradient of particle size, but the core is not limited to having such a gradient. The absorbing material within the core can exhibit a gradient in the z-direction with respect to particle size, absorption characteristics, particle number, or combination thereof. From Figure 10A, it is clear that the fibers 401 are more spaced apart in layer 107a, providing larger pores 405 and therefore a lower density compared to layers 107b and 107c.

[0105] Methods for achieving such a gradient of absorbent materials are described in more detail below. However, in short, superabsorbent particles can be introduced into bulky nonwovens by any suitable process, including scattering, air stream impregnation, and in-situ polymerization. In some embodiments, superabsorbent particles are introduced through an air stream to the least dense side of the bulky nonwoven (i.e., face 404). The superabsorbent particles penetrate the bulky nonwoven, and at least a portion of the superabsorbent particles are trapped and retained by the fibers of the bulky nonwoven. The superabsorbent particles can exhibit a wide particle size distribution. Larger particles will generally be trapped and retained in the relatively less dense areas of the bulky nonwoven, and smaller particles will generally be trapped and retained in the relatively dense areas of the bulky nonwoven. The result is a multilayer absorbent web with different particle size populations in each of layers 107a-107c. At least some of the superabsorbent particles deposited on the fibrous structure 106, such as fine particles, are not captured by the bulky nonwoven fabric and can pass through. In some embodiments, to avoid the accumulation of such fine particles in the particle applicator, which may result in filter clogging and an undesirable particle size distribution in the final product, the fine particles, SAP 400d, are collected and deposited on the fluff / pulp mixture 403, which forms a pulp layer of the lower fibrous structure 130.

[0106] The SAP filtration performance of bulky nonwoven fabrics is due to their role in increasing the concentration of larger particles in the upper region of the fabric and the concentration of smaller particles in the lower region. Such SAP filtration can be controlled by the particle size distribution of the SAP and the density of the bulky nonwoven fabric.

[0107] In some embodiments, the fibrous structure 106 is a layer of bulky nonwoven fabric containing superabsorbent particles (SAP) 400a-400c. The bulky nonwoven fabric of the fibrous structure 106 can be a high-loft, low-density, and thick nonwoven fabric. In some embodiments, the bulky nonwoven fabric of the fibrous structure 106 is made from one of the following fibers: polyethylene (PE) fibers, polypropylene (PP) fibers, polyethylene terephthalate (PET) fibers, or a combination thereof. In some embodiments, the fibers of the bulky nonwoven fabric are or contain binary fibers such as PE / PP fibers or PE / PET fibers. For example, the fibrous structure 106 may be or contain an air-penetrating bonded nonwoven fabric containing PE / PET binary fibers. In the case of a multilayer bulky nonwoven fabric as shown in Figures 10A-10D, each of the layers 107a-107c may have a different fiber combination, a different fiber density, or a different porosity, or a combination thereof. In some embodiments, different layers 107a to 107c are arranged such that layer 107c has a higher density than layer 107b, and layer 107b has a higher density than layer 107a. Methods for achieving different fiber densities and / or porosity are described in more detail below.

[0108] As shown in the figure, the core 100 exhibits a gradient distribution of adhesive 402a to 402c in the z direction (i.e., from the upper surface 404 of the core 100 to the lower surface 406 of the core 100). In Figure 10A, the adhesives 402a to 402c have a gradient with respect to amount (e.g., weight, volume, concentration, and / or packing density), such that a smaller amount of adhesive 402a is positioned and held in the upper layer 107a of the fibrous structure 106. The amount of adhesive 402b positioned and held in the intermediate layer 107b of the fibrous structure 106 is greater than the amount of adhesive 402a positioned and held in the upper layer 107a of the fibrous structure 106. The amount of adhesive 402c positioned and held in the lower layer 107c of the fibrous structure 106 is greater than the amount of adhesive 402b positioned and held in the intermediate layer 107b of the fibrous structure 106.

[0109] The method for achieving such a gradient of adhesives is described in more detail below. However, in short, to enhance the capture of superabsorbent particles by the bulky nonwoven fabric of the fibrous structure 106, adhesives 402a-402c, which are tackifying adhesives, are added as a surface coating to some or all of the fibers of the bulky nonwoven fabric of the fibrous structure 106. The tackifying adhesives 402a-402c can be low-viscosity adhesives sprayed onto the bulky nonwoven fabric so that the adhesives 402a-402c coat the fibers through the bulky nonwoven fabric. The addition of adhesives 402a-402c can function to increase the number of superabsorbent particles held by the bulky nonwoven fabric as the air stream carrying the superabsorbent particles passes through the bulky nonwoven fabric. Furthermore, adhesives 402a to 402c can function to improve the wettability and dryness of the fibrous structure 106, which is a bulky nonwoven fabric-SAP composite, during the manufacturing process, transport, and final use of the absorbent article product.

[0110] Figures 10B-10D further show the distribution of SAP and adhesive within the bulky nonwoven fabric. Referring to Figure 10B, it is clear that larger SAP particles are trapped in the low-density sections of the fibrous structure 106, while as the SAP particle size decreases, the fibrous structure 106 passes through the filter and is trapped in its high-density sections. The SAP lost by complete filtration through the fibrous structure 106 can be converted into SAP granules.

[0111] Referring to Figure 10C, it is further clear that the concentration of the hot melt adhesive is high in the high-density sections of the fibrous structure 106 and low in the low-density sections of the fibrous structure 106. For HMA within the fibrous structure 106, SAP loss can be considered low or absent.

[0112] Referring to Figure 10D, it is further evident that, with or without the use of a hot-melt adhesive, the addition of a nonwoven trapping sheet 1208 (e.g., spunbond or meltblown) provides a fibrous structure 106 capable of capturing all or substantially all of the SAP, thus resulting in no or substantially no SAP loss.

[0113] Table 1 below sets forth some exemplary parameters, design options, and processing options for a base material that can be used when designing a fibrous structure 106 in accordance with the disclosure of the present invention. The parameters and options listed in Table 1 are not limiting, and other parameters, options, and variables can be used to design a desired fibrous structure. By selecting the type of fiber, fiber pretreatment (i.e., treatment prior to SAP deposition), SAP deposition parameters, and post-SAP deposition treatment, a fibrous structure with desirable properties can be designed. Table 1 lists 11 exemplary fibrous structure designs and their options. However, any combination of the variables described in Table 1 can be used to design a fibrous structure. Furthermore, additional variables and options not described in Table 1 can also be used to design a fibrous structure. Figures 10E-10J show some exemplary schematic diagrams of certain fiber preparation and SAP deposition processes. However, the methods of the present invention are not limited to these specific sequences and can include any number of substitutions and modifications without departing from the scope of the disclosure of the present invention.

[0114] (Table 1) Table 1 - Fibrous structure options and manufacturing variables TIFF0007871334000001.tif198169 TIFF0007871334000002.tif82169

[0115] Figures 10E–10H illustrate some exemplary fibrous structure preparation techniques. In Figure 10E, the fibrous structure is exposed to heat to bulk up the fibrous structure. After bulking, HMA is sprayed onto the fibrous structure from its bottom surface. At least two factors contribute to the formation of a gradient HMA distribution throughout the fibrous structure in terms of HMA concentration, including: (1) HMA impacts the fibers toward the bottom of the fibrous structure, resulting in more HMA contacting and adhering to the fibers toward the bottom of the fibrous structure than to the top of the fibrous structure; and (2) the fibrous structure becomes denser toward the bottom of the fibrous structure than to the top of the fibrous structure, further promoting HMA-fiber capture. Next, SAP is added to the fibrous structure from its top surface opposite the surface onto which HMA was sprayed. The SAP filters through the fibrous structure. The SAP can be retained within the fibrous structure of the fibrous structure by its fibers through confluence and by HMA through adhesion. Larger SAP particles tend to be trapped towards the top of the fibrous structure, at least in part, because the fibrous structure in this example has a gradient density, with higher density towards the top. Higher density allows the fibers to spread further apart, sufficient to trap larger SAP particles, while allowing smaller SAP particles to filter deeper into the fibrous structure. As SAP filters deeper into the fibrous structure, the concentration of HMA increases towards the bottom, causing the SAP to collide with more HMA particles. Similarly, as SAP filters deeper into the fibrous structure, the fibrous structure becomes denser, with fibers positioned closer together, causing the SAP to collide with more fibers. This allows the fibrous structure to trap SAP particles that were not trapped towards its top. Some SAP particles are too small to be trapped by the fibers or HMA and can be filtered through the entire fibrous structure. Such SAP particles may be SAP granules, which can be recovered and diverted for combination with pulp.

[0116] Referring to Figure 10F, in some embodiments, the capture layer is bonded to the bottom of the fibrous structure. As the SAP is deposited and filtered through the fibrous structure, the capture layer captures the SAP particles so that the SAP particles are incorporated as part of the fibrous structure and are not recovered or bypassed.

[0117] Referring to Figure 10G, in some embodiments, the fibrous structure is not bulked up before the addition of SAP. The SAP can be introduced into the fibrous structure with a heated forced airflow so that the bulking and / or tackification of the fibrous structure occurs simultaneously with the addition of SAP.

[0118] Referring to Figure 10H, in some embodiments, the fibrous structure undergoes selective densification at its base, forming a trapping layer. When the SAP is deposited, this trapping layer thus captures all of the SAP, including the SAP granules, so that the SAP granules are incorporated as part of the fibrous structure, recovered, and not bypassed.

[0119] glue In some embodiments, the adhesive is applied to a bulky nonwoven fabric (or other fibrous structure) by carrying it in an air stream. The air can be heated, which expands the fibrous network of the bulky nonwoven fabric, resulting in increased bulkiness, and thus facilitating the introduction and penetration of the adhesive into the fibrous network by creating a more open network. In some embodiments, the adhesive is applied to the fibers as a uniform spray. The viscosity of the adhesive can be varied by temperature. Therefore, the viscosity of the adhesive at the time of application can be controlled by controlling the temperature of the adhesive at the time of application.

[0120] In some embodiments, the adhesive is in the form of particles, including spherical particles, or fibers. In some such embodiments, the adhesive is added as a hot-melt spray, which may be more suitable for creating a gradient adhesive distribution within the fibrous structure. In embodiments where the adhesive is in the form of particles, an additional heating step may be used to activate the adhesive before the addition of the SAP. Since the adhesive can be added to the fibrous structure in the opposite direction to the addition of the SAP, the gradient of the adhesive distribution within the fibrous structure is the opposite (opposite direction) to the gradient of the SAP distribution within the fibrous structure.

[0121] In some embodiments, a binder or matrix is ​​provided for stabilizing and partially immobilizing SAP particles within a fiber network by adding an adhesive in the liquid phase / spray application of a hot-melt adhesive. In the extrusion process, the hot-melt adhesive is forced through small holes and, together with air filamentation, generates elongated polymer strands or fibers of HMA. When deposited on a substrate, the elongated polymer strands of HMA establish a fiber network capable of holding SAP particles.

[0122] Alternatively, powdered hot-melt adhesive particles can be mixed with superabsorbent particles, and the mixture of non-adhesive hot-melt particles and superabsorbent particles is added to a bulky nonwoven fabric. When heat is applied to the composite, the hot-melt adhesive powder melts and bonds the SAP to the bulky nonwoven fabric. The application of heat can be achieved, for example, by heated forced airflow, an oven, or IR irradiation.

[0123] By selecting the hot melt material and process in this way as design elements, particularly improved product performance can be achieved. In another application, the ratio of hot melt particles to superabsorbent particles is selected to achieve an optimal balance between drying integrity and suppression of SAP swelling. The ratio of SAP particles to hot melt particles determines, for example, how many bonding points can be contributed to by the hot melt particles per SAP particle. This ratio is determined from the weight percentage of each component, particle size distribution, and polymer density. The hot melt particles are commercially available materials from Abifor. By selecting the hot melt material and process in this way as design elements, particularly improved product performance can be achieved. In some applications, water-sensitive hot melt particles can be used as a mechanism to increase the void space (swelling volume). Specifically, a hot melt sensitive to wetting and therefore to the acceptance of liquid into the absorbent core pocket (e.g., SAP-based hot melt) is selected. These hot melt particles decompose when the surrounding SAP particles swell due to liquid absorption. This releases the SAP particles from the hot melt bonds, allowing them to expand freely. An example of a water-soluble hot melt is modified polyvinyl alcohol resin (Gohsenx L series, Nippon Synthetic Chemical Industry Co., Ltd.). An example of a water-sensitive hot melt is Hydrolock (HB Fuller).

[0124] Referring to Figures 11A and 11B, an exemplary two-component fiber 500 is shown, which can form all or part of the bulky nonwoven fabric of the fibrous structure 106. The two-component fiber 500 can be a core / sheath (also called core / shell) particle comprising a fiber sheath 502 of a first thermoplastic material and a fiber core 504 of a second thermoplastic material. The second thermoplastic material may have a higher softening point and a higher melting point than the first material. For example, the core 504 may be made of polypropylene, while the sheath 502 may be made of polyethylene (PE / PP fiber). As will be described in more detail below, the two-component fiber 500 can function as an adhesive for capturing and retaining SAP during its deposition. Thus, in some such embodiments, when a bulky nonwoven fabric containing the two-component fiber is used, no adhesive is added to the bulky nonwoven fabric. Referring to Figures 11C to 11F, the bulky nonwoven fabric containing two-component fibers, fiber 500a is exposed to heating 501, and the sheath 502a is heated to a temperature at which it softens (softening point temperature) but does not melt or melt completely, thereby forming a two-component fiber 500b with a softened sheath 502b. Next, the two-component fiber 500b bonds with the superabsorbent particles 400 in the bonding step 503. Since the sheath 502b is softened, the SAP 400 adheres to the sheath 502b. Next, the two-component fiber 500b is cooled 505 to a temperature below its softening point so that the sheath 502b rehardens, forming a two-component fiber 500c with a rehardened sheath 502c. Thus, the SAP 400 adheres to the sheath 502c. Therefore, heating a two-component bulky nonwoven fabric to a temperature near or above the softening point of a low-melting-point thermoplastic material, but lower than the softening point of a high-melting-point thermoplastic material, and then applying SAP to this bulky nonwoven fabric, provides an exemplary method for adhering SAP to the fibers of the fibrous structure 106. Without being bound by theory, it is assumed that the outer sheath 502 softens and becomes tacky when heated to or near its softening temperature. When an air stream filled with superabsorbent particles passes through the heated bulky nonwoven fabric, the tacky surface of the sheath can facilitate the capture and retention of the superabsorbent particles, thereby improving the drying and wetting cohesion of the nonwoven fiber mixture filled with superabsorbent particles.

[0125] Crepe-processed spunbond In some embodiments, the fibrous structure is or includes a crepe spunbond nonwoven fabric. Exemplary crepe spunbond nonwoven fabrics are shown in images in Figures 20A-20E. SAP can be trapped and held within the micropockets of the crepe spunbond and distributed in a pattern (due to the bonding pattern of the particular spunbond used). Such an SAP-absorbing structure can exhibit high permeability even after the SAP has swollen, as the clusters of SAP are separated from each other. Referring to Figures 20A-20E, the loop pattern, loop frequency, and loop height are directly induced by the bonding pattern and level of crepe processing of the base spunbond sheet. A coarser bonding pattern will result in a loop pattern with low frequency but high loop height. A higher level of crepe processing leads to greater out-of-planar fiber deformation, resulting in larger loops, increased bulk, and therefore lower web density. Loop structure, e.g., size and volume, can be controlled by the selection of fundamental spunbond parameters such as bonding pattern and fiber size, along with the crepe level. Regions with fiber loops act as micropockets that can contain and encapsulate particles, such as superabsorbent particles, in a defined pattern. Similarly, by stacking at least two crepe-spunbond webs at different crepe levels, a configuration with a gradient in particle size encapsulation can be constructed. In addition, crepe processing adds flexibility, pliability, and extensibility to the resulting web structure. In some embodiments, the crepe-spunbond web includes z-oriented fiber segments that increase compressive resistance and the z-direction flow of liquid within the spunbond web.

[0126] The crepe process helps to impart resilient extensibility to the crepe-cured spunbond web and can be used to further enhance the internal containment of SAP particles, especially in the case of webs crepe-cured to a level higher than 20% ± 3%. This can be achieved by stretching the crepe-cured spunbond web to a level lower than the web's crepe-curing level before adding the SAP particles, and then returning the web to its original state after adding the SAP particles, thereby increasing the degree of SAP particle containment within the web.

[0127] In some embodiments, the fibrous structure or base layer (layer 118) is creped online (e.g., during manufacturing in the system shown in Figure 12A) as a full-width material sheet or as strips or sections (i.e., before or after separation into sections). The crepe level of a particular strip or layer can be controlled to provide the appropriate SAP particle capture required for the absorption structure. In some embodiments, a hot-melt adhesive is added to the creped spunbond to enhance SAP particle capture therein.

[0128] In some embodiments, the fiber layer, whether crepe spunbond, BNW, or another nonwoven fabric, can be subjected to vibration to further facilitate the distribution of SAP within it.

[0129] Processes and Systems In some embodiments, the disclosure of the present invention includes systems and processes for making absorbent cores and absorbent articles disclosed herein.

[0130] Referring to Figure 12A, an exemplary system and process schematic is shown and explained. Using system 1200, an absorbent core according to the disclosure of the present invention can be formed. To make an exemplary absorbent core, a fibrous structure 106 is dispensed from a spool 1202. The fibrous structure 106 passes through a roller 1201 to a fiber adhesiver 1204. The fibrous structure 106 passes through the fiber adhesiver 1204, and as it exits the fiber adhesiver 1204, the fibers of the fibrous structure 106 exhibit increased tackiness compared to the tackiness of the fibers before entering the fiber adhesiver 1204. In some embodiments, the fiber adhesiver 1204 is or includes an oven or other device that exposes the fibrous structure 106 to heat 1205. In some such embodiments, the heat is sufficient to raise the temperature of the fibrous structure 106 such that bulking occurs in at least a portion of the fibrous structure 106, resulting in a bulked nonwoven fabric. For example, Figures 12B and 12C show the fibrous structure 106 before and after bulking, respectively. Bulking can enhance the function of the fibrous structure 106 in receiving, capturing, and / or filtering SAP according to the size of the SAP, etc. When the fibers of the fibrous structure 106 are two-component fibers, heat from the fiber adhesiver 1204 can result in softening of the fiber sheath, as illustrated and described above in relation to Figures 11C-11F. Figures 17A and 17B show a more detailed illustration of bulking of a multilayer nonwoven fabric 106 having layers 107a-107c.

[0131] Although not shown, in some embodiments, the fiber densifier 1204 is or includes an IR generator for selectively impacting a certain portion or surface of the fibrous structure 106 with IR radiation. Using IR radiation, the portion of the fiber it impacts can be selectively densified (opposite to bulking). For example, IR radiation can be impacted only on the bottom surface 1207 of the fibrous structure 106 to densify only the bottom surface 1207 of the fibrous structure 106. Densification of the bottom surface 1207 of the fibrous structure 106 can make it easier for the fibrous structure 106 to hold smaller sized SAP particles by forming a dense bottom surface 1207 of the fibrous structure that can capture and hold SAP particles that are too small to be captured in other sections of the fibrous structure 106.

[0132] In some embodiments, the fiber adhesiver 1204 is or includes an adhesive applicator 1206, such as an adhesive spray gun. The adhesive applicator 1206 can coat the fibers with adhesive by applying adhesive (e.g., a low-tack adhesive) to the fibrous structure 106 as it passes through it, thereby increasing the tackiness of the fibers. In some such embodiments, the adhesive applicator 1206 is positioned on only one side of the fibrous structure 106 so that the adhesive is sprayed onto or applied to the fibrous structure from only one side. For example, the adhesive applicator 1206 can be positioned below the fibrous structure 106 (as shown in the figure) so that the adhesive is applied to the bottom surface 1207 of the fibrous structure 106. In some such embodiments, by applying the adhesive on and through the bottom surface 1207, a gradient distribution of adhesive is achieved within the body of the fibrous structure 106 as shown in Figures 10A-10D. The fibers on or near the base surface 1207 collide with the adhesive before collisions occur between fibers further away from the base surface 107, so that more adhesive adheres to and is held there by the base surface 1207 or near the top surface 1209 than by the top surface 1209 or near it.

[0133] In some embodiments, the fiber tackifier 1204 includes the use of IR radiation, heating, adhesive application, or any combination thereof. In some embodiments, bulky nonwoven fabrics are bulked using mechanical methods such as brushing. For example, in some embodiments, nonwoven fabrics or bulky nonwoven fabrics can be bulked by the method disclosed in U.S. Patent Application Publication No. 2019 / 0290505, filed March 22, 2019. In some embodiments, the forced airflow 1218 (Figure 12B) is hot enough to tackify the fibrous structure 106. In some such embodiments, the heat from the forced airflow 1218 is used to tackify the fibrous structure 106. In other embodiments, the heat from the forced airflow 1218 is combined with one or more of the following to tackify the fibrous structure 106: brushing, IR radiation, other heating (e.g., oven heating), and adhesive application.

[0134] In some embodiments, the adhesiveized fibrous structure 106 is bonded to a nonwoven trap sheet 1208. The nonwoven trap sheet 1208 can be a denser nonwoven fabric than the fibrous structure 106. In some embodiments, the nonwoven trap sheet 1208 is not a bulky nonwoven fabric. The nonwoven trap sheet 1208 is dispensed from a spool 1210. Adhesive can be applied to the nonwoven trap sheet 1208 by an adhesive spray gun 1212 or the like. The nonwoven trap sheet 1208 can then pass over the roller 1211 to the bonding roller 1214. The adhesiveized fibrous structure 106 is then bonded to the nonwoven trap sheet 1208 on the bonding roller 1214, in which case the adhesive on the nonwoven trap sheet 1208 provides adhesion between the nonwoven trap sheet 1208 and the adhesiveized fibrous structure 106. During use, the high density of the nonwoven trapping sheet 1208 allows it to trap SAP particles that are too fine to be trapped by the fibrous structure 106, so that the fine SAP particles can pass through the fibrous structure 106. In some embodiments, the nonwoven trapping sheet 1208 is not used.

[0135] The adhesive fibrous structure 106 bonded to the nonwoven trapping sheet 1208 then proceeds to the SAP impregnator 1216. The SAP impregnator 1216 is or may include an air-forming step for SAP deposition. A detailed diagram of the SAP impregnator 1216 is also shown in Figure 12D. The SAP impregnator 1216 generates a high-speed forced airflow 1218 to which the SAP 400 is combined within the chamber 1215. The SAP-containing airflow 1220 then flows down toward the fibrous structure 106 and is filtered through it. The high velocity of the SAP-containing airflow 1220 helps to reduce or prevent the accumulation of SAP 400 on the top surface of the fibrous structure, allowing the SAP to filter through it. The fibrous structure 106 acts as a filter, capturing and retaining SAP particles. Because the fibrous structure 106 is adhesive, the SAP 400 adheres to its fibers. The SAP 400 can be dispersed within the fibrous structure 106 as shown in Figures 10A-10D. In some embodiments, all SAP 400 is trapped within the fibrous structure 106. For example, in some embodiments, the bottom layer of the fibrous structure 106 (e.g., 107c) has a sufficient fiber density to trap and retain all SAP 400 in the SAP-containing airflow 1220, or the nonwoven trapping sheet 1208 has a sufficient fiber density to trap and retain all SAP 400 in the SAP-containing airflow 1220. However, in other embodiments, at least some of the SAP 400, SAP granules 400d, are filtered through the fibrous structure 106 (as shown in Figure 12D). Such granules can be recycled in a loop 1217 that returns to the top of the fibrous structure 106. However, in other embodiments, such SAP granules 400d are recovered and / or diverted to a secondary air-forming process for addition to the pulp layer 130, as shown in the SAP bypass route 1224 in Figure 12A, which will be described in more detail below. Since filtered SAP can be bypassed, in some embodiments, the manufacturing process of the core 100 results in no or virtually no SAP loss. Although not shown, in some embodiments, an adhesive is added to the SAP-containing airflow 1220 or forced airflow 1218. In some embodiments, SAP is selectively deposited at selected locations on the fibrous structure 106.For example, the SAP addition can be varied over time and / or space using induction valves, pulsed SAP deposition, blinds to prevent SAP deposition, and other such methods to generate a y-direction gradient (MD) of the SAP. In some embodiments, the properties of the SAP can be changed depending on the expected position of the SAP within the core 100. For example, the position can be predicted based on the particle size of the SAP.

[0136] After SAP is added to the fibrous structure 106, the fibrous structure 106 proceeds to the layer separator 1230. The layer separator 1230 can cut, slash, or otherwise separate the fibrous structure 106 into multiple sections, such as the four sections shown in Figure 4A. The layer separator 1230 may be or include a knife or other cutting or slitting device for separating the fibrous structure 106. For example, Figures 12E and 12F show the fibrous structure 106 before and after passing through the knife 1232 of the layer separator 1230 to form fibrous structure sections 106a to 106d, respectively. In embodiments including a nonwoven trapping sheet, the nonwoven trapping sheet may or may not be cut together with the fibrous structure 106. In another embodiment, the fibrous structure 106 is not slit or cut. Figure 12G shows an exemplary core 100 including cut nonwoven trapping sheets 1208a-1208d positioned below fibrous structure sections 106a-106d. The core 100 in Figure 12G is otherwise identical to that in Figure 5. In some embodiments, cutting the fibrous structure 106 into fibrous structure sections 106a-106d results in densification of the lateral edges of the fibrous structure sections 106a-106d as a result of contact with the cutting device. For example, each of the fibrous structure sections 106a-106d in Figure 12F has a densified lateral edge 103. Such densified lateral edges can facilitate suction along with retention of SAP in the fibrous structure sections 106a-106d (as a result of compaction by denser fibers). Figure 18 shows another exemplary layer separator 1230, which includes a circular knife 1232, such as a roll (crush cut), positioned adjacent to one side of the fibrous structure 106 for slits, and an opposing roller 1231, such as an anvil, positioned on the opposite side for slits. As the fibrous structure 106 passes between the roller 1231 and the knife 1232, the fibrous structure 106 is separated into fibrous structure sections 106a to 106d.

[0137] The fibrous structure 106, thus cut, then proceeds to the bonding roller 1240, where it is bonded to the intermediate nonwoven sheet 118. The intermediate nonwoven sheet 118 can be dispensed from the roller 1242. In some embodiments, an adhesive (e.g., 120 shown in Figure 5) is added to the intermediate nonwoven sheet 118 by an adhesive applicator 1244 or the like before it is bonded to the fibrous structure 106. The intermediate nonwoven sheet 118 and the fibrous structure 106 pass through the bonding roller 1240 and are pressed against each other by the force from the roller.

[0138] Next, the bead adhesive applicator 1250 adds the adhesive bead to the intermediate nonwoven sheet 118 in the spaces between sections of the fibrous structure 106 (for example, a bead 122 as shown in Figure 5).

[0139] Next, the upper nonwoven sheet 116 is bonded with the fibrous structure 106 and the intermediate nonwoven sheet 118. The upper nonwoven sheet 116 is distributed from the spool 1252, passes through the roller 1254, and is bonded with the fibrous structure 106 and the intermediate nonwoven sheet 118 by the bonding roller 1260 to form the upper absorbent structure 102. In some embodiments, the bonding roller 1260 includes one or a series of rollers that compress the upper nonwoven sheet 116, the fibrous structure 106, and the intermediate nonwoven sheet 118 together. In other embodiments, the bonding roller 1260 is or includes a grooved forming roller 1262 (Figures 12H-12L) having a contoured surface to form a corrugated shape on the upper nonwoven sheet 116, resulting in a wavy upper nonwoven sheet 116 as shown in Figure 5.

[0140] The grooved forming roller 1262 includes a roller body having a series of peaks 1270 and valleys 1272. As a substantially flat upper nonwoven sheet 116a passes over the grooved forming roller 1262, the upper nonwoven sheet 116a conforms to the corrugated surface (peaks and valleys) of the forming roller body 1266. In some such embodiments, air suction is provided to pull the upper nonwoven sheet 116a towards the corrugated surface of the forming roller body 1266. Thus, a corrugated upper nonwoven sheet 116b is formed. The bonding roller 1260 may also include a lower roller 1264, which may have a smooth surface rather than a corrugated surface for compressing the upper nonwoven sheet 116, the fibrous structure 106, and the intermediate nonwoven sheet 118 together to form the upper absorbent structure 102.

[0141] The upper absorption structure 102 then passes through the roller 1280 to the bonding roller 1282 in order to bond with the lower absorption structure 104. In some embodiments, adhesive is applied to the upper absorption structure 102 by an adhesive applicator 1284 (e.g., adhesive 128 in Figure 5).

[0142] To create the lower absorption structure 104, a nonwoven sheet 132 is dispensed from a spool 1300 and adhesive is applied to it by an adhesive applicator 1302. The nonwoven sheet 132 is passed to a core mold 1306 (e.g., a vacuum drum) where pulp 1304 is applied to the nonwoven sheet 132. In some embodiments, SAP granules 400d from a bypass stream 1224 are combined with pulp 1304, pass through an X-forming roller 1308, and are sprayed with adhesive (e.g., 134a and / or 134b in Figure 5) by an adhesive applicator 1310, and folded on a folding plate 1312, thereby forming the lower absorption structure 104. In some embodiments, the pulp 1304 is formed using a hammer mill. The lower absorbent structure 104 then proceeds to the coupling roller 1282, where it is coupled with the upper absorbent structure 102 to form a sheet of core material 100, which can then be recovered onto a spool for subsequent use (e.g., incorporation into an absorbent article). In some embodiments, the core 100 is not recovered but immediately combined with an absorbent article. In some embodiments, the core 100 does not include the lower absorbent structure 104.

[0143] Figure 19 shows in more detail some of the manufacturing equipment for the lower absorption structure 104. The nonwoven sheet 132 is unwound from the spool 1300, passes through the roller 1301, and undergoes hot melt addition through the applicator 1302. Inside the core forming chamber 1603, an air stream into the chamber carries and mixes the fluff pulp fibers 1304 and SAP granules 400d to form a mixture 1303 of SAP and fluff pulp, which is then drawn onto the core-wrap nonwoven sheet 132 by a vacuum 1307 and deposited thereon. The core forming drum 1306 may include a mesh screen 1309 on which the nonwoven sheet 132 is placed, and the vacuum 1307 draws air through the mesh 1309 in the core forming area to form a fluff pulp core with SAP granules 400d thereon. The transfer roller 1308 pulls the nonwoven sheet 132 from the core forming drum 1306 with the fluff and SAP on it, and optionally allows it to be subjected to hot melt application through the applicator 1310 to provide core integrity.

[0144] Figure 13 is a flowchart of an exemplary method for making an absorbent core disclosed herein. Method 1300 includes: depositing SAP onto a bulky nonwoven fabric, 1302; separating the bulky nonwoven fabric into a plurality of longitudinal sections, 1304; placing a first nonwoven sheet on a first face of a bulky nonwoven fabric section, 1306; placing a second nonwoven sheet on a second face of the bulky nonwoven fabric, the second face being opposite to the first face, 1308; adhering the second nonwoven sheet to the first nonwoven sheet at locations between the plurality of longitudinal sections of the bulky nonwoven fabric, 1310; and forming a corrugated shape on the second nonwoven sheet, thereby forming an upper absorbent structure, 1312.

[0145] Figure 14 is a flowchart of an exemplary method for making an absorbent core disclosed herein. Method 1400 includes: a step of tackifying a bulky nonwoven fabric, 1402; a step of placing a nonwoven trapping sheet on the bulky nonwoven fabric, 1404; a step of depositing SAP on the bulky nonwoven fabric from a high-speed SAP-containing airflow, 1406; a step of separating the bulky nonwoven fabric into a plurality of longitudinal sections, 1408; a step of placing a first nonwoven sheet on the nonwoven trapping sheet, 1410; a step of placing a second nonwoven sheet on the second surface of the bulky nonwoven fabric on the opposite side of the first nonwoven sheet using a grooved forming roller, 1412; a step of adhering the second nonwoven sheet to the first nonwoven sheet at locations between the plurality of longitudinal sections of the bulky nonwoven fabric, 1414; and a step of forming a corrugation on the second nonwoven sheet, thereby forming an upper absorbent structure, 1416.

[0146] Figure 15 is a flowchart of an exemplary method for making an absorbent core disclosed herein. Method 1500 includes the step 1502 of depositing pulp and SAP onto a nonwoven sheet. In some embodiments, the SAP is reused from SAP filtered through a bulky nonwoven fabric, as in Method 1300 or 1400. Method 1500 includes the step 1504 of folding the nonwoven fabric around the pulp and SAP to form a lower absorbent structure. Method 1500 includes the step 1506 of combining the lower absorbent structure with an upper absorbent structure. The upper absorbent structure in step 1506 may be, for example, one formed by Method 1300 or Method 1400.

[0147] Extruded nonwoven fabric In some embodiments, the fibrous structure is or comprises an extruded nonwoven fabric containing SAP. For example, such a nonwoven fabric can be formed according to a method disclosed in U.S. Patent No. 5,720,832, which is incorporated herein by reference in whole. Thus, rather than adding SAP to an existing bulky nonwoven fabric, a nonwoven-forming polymer (e.g., polypropylene, polyethylene acetate) is extruded around superabsorbent particles to form an absorbent web of nonwoven fibers that surrounds and encapsulates the superabsorbent material within the SAP-nonwoven composite. The superabsorbent material within such a pre-formed SAP-nonwoven composite may be in particulate or fibrous form.

[0148] For example, referring to Figure 21, a nonwoven polymer 2101 is extruded from an extruder 2108 around superabsorbent particles 2104 to form an absorbent web of nonwoven fibers, an SAP-nonwoven composite 2106, which surrounds and encapsulates the superabsorbent material.

[0149] Fibrous structural additives In some embodiments, the fibrous nonwoven fabric (bulky or in-situ extruded) contains fibers and additives that impart additional properties to the absorbent structure, in addition to its properties for stabilizing SAP particles. For example, without limitation, the fibrous structure may include elastomer fibers that provide elasticity, stretchability, and biocompatibility; wetting agents, odor control agents, ion exchange resins, cellulose fibers such as microfibrillated cellulose (MFCs) that provide and / or enhance liquid handling capabilities; and smart fibers.

[0150] Profile formation of absorber structure In some embodiments, the SAP varies by region within the absorbent core. For example, the type of SAP, the amount of SAP, the particle size of SAP, and / or the properties of SAP can be varied. For instance, SAP in one or more regions may have relatively low permeability, such as on the sides of the core, while SAP in one or more other regions may have relatively high permeability, such as in the central region (groove).

[0151] In some embodiments, the absorbent core has an absorbent capacity profiled in the machine direction (MD) coinciding with the longitudinal centerline 110 shown in Figure 4A. For example, the amount of SAP injected can be varied in the machine direction. In some embodiments, the absorbent core has an absorbent capacity profiled in the width direction (CD) coinciding with the transverse centerline 108 shown in Figure 4A. For example, the SAP filling can be varied in different SAP regions in the width direction, and the width of the SAP regions can be varied. Similarly, the number of SAP regions can be varied.

[0152] The cutting length of the absorbent fiber section can be varied in each channel. Figure 22 shows a core 100 having SAP areas 2202a and 2202b. SAP area 2202a can differ from SAP area 2202b in terms of the amount of SAP filling, the type of SAP, the particle size of the SAP, the properties of the SAP, or a combination thereof. Figure 23 shows a core 100 having a relatively short SAP area 2302a on the side and a relatively long SAP area 2302b in the center. Figure 24 shows a core 100 having SAP areas 2402a at the longitudinal ends of the core 100 and an SAP area 2402b in the center. Figure 25 shows a core 100 having an SAP area 2502a extending diagonally with respect to the longitudinal centerline of the core 100, a triangular SAP area 2502b, and a circular SAP area 2502c located in the center. In each of Figures 23-25, each different SAP area may be the same as or different from other SAP areas in terms of SAP filling volume, type, size, and / or characteristics.

[0153] Figures 26 and 27 show embodiments of the geometric arrangement of SAP deposits that can be used in the core 100 disclosed herein. Each SAP area 2800 (shown as an unshaded area within the core 100) is separated from other SAP areas 2800 by gaps 2900 that do not contain SAP or other absorbent material. As described elsewhere herein, portions of the gaps 2900 can function as channels and / or folds in the core 100. Each separate SAP area 2800 may be the same as or different from other SAP areas in terms of the amount, type, size, and / or properties of the SAP filling.

[0154] In some embodiments, the SAP varies in both CD and MD using molded absorbent sections, etc. By stacking absorbent regions having multiple strips of absorbent regions of different lengths, it is possible to achieve absorbent regions with different shapes and orientations, having different SAP and SAP filling amounts.

[0155] In some embodiments, the fiber section is cut to have a width that varies along the longitudinal centerline of the core. For example, Figure 28 shows a core 100 having a fiber section 106b containing SAP, the fiber section including a centrally located enlarged region 133 that extends closer to the lateral side edge 113 of the core 100 than to a narrower region 137. The core 100 also includes a fiber section 106a containing SAP. Fiber section 106a may contain less SAP filling than fiber section 106b. From Figure 28, it is clear that the SAP regions can be shaped and positioned so that a larger amount of highly absorbent SAP can be strategically placed in the groin region. The fiber section can be cut to have a curved perimeter rather than a straight one. In some embodiments, multiple (e.g., two) regions with relatively high SAP content can be formed from a single fibrous structure with little to no waste. For example, a single sheet with a fibrous structure can be cut to have an S-shaped cutting pattern, and then one half of the S-shaped sheet can be turned over and moved to a position that is phase-shifted relative to the other half of the sheet so that the patterns match.

[0156] Modes and variations In some embodiments, the absorbent cores disclosed herein achieve a low-density, high-volume, bulky, and high-loft absorbent configuration, providing a soft fit and rapid absorption properties. In certain embodiments, the absorbent core is a multilayer composite core configuration having both an upper absorbent configuration and a lower absorbent configuration. Each layer or configuration can be adapted to have a specific function, such as absorption or distribution.

[0157] The absorbent core disclosed herein can be well fitted to the user, particularly in the narrow area between the legs. The absorbent core can easily adopt a "W-shaped" configuration, thereby narrowing the core and reducing lateral fluid flow to the sides of the core, thereby reducing leakage from the sides of the absorbent product.

[0158] In some embodiments, the core 100 has a width in the range of approximately 70 to 200 mm, 80 to 170 mm, 90 to 150 mm, or 100 to 130 mm. In some embodiments, the core 100 has a basis weight of approximately 30 to 60 gsm or more. In some embodiments, the thickness of each fibrous structural section 106a to 106d is 2 to 10 mm, 4 to 8 mm, or 5 to 7 mm. In some embodiments, the thickness of the pulp layer 130 is 2 to 10 mm, 4 to 8 mm, or 5 to 7 mm. In some embodiments, the thickness of the core is 5 to 20 mm, 8 to 15 mm, 10 to 12 mm, or 6 to 10 mm. The width of the core can be approximately 100 mm for infant diapers, and 140 to 150 mm, or 80 to 170 mm for adult diapers. The lower core configuration may have the same width as the upper core configuration, or be slightly larger than the composite of materials constituting the upper core configuration. In some embodiments, the BNW has a thickness of 1 to 3 mm depending on its basis weight and density. In some embodiments, the lower absorbent configuration (e.g., pulp layer) has a thickness of less than about 2 mm, or 0.5 to 1.7 mm, and has a low basis weight. In some embodiments, the spunbond nonwoven fabric disclosed herein has a thickness of less than 0.2 mm. In certain embodiments, the absorbent core disclosed herein is prefabricated and can be spooled or garnished for shipping and use in diaper lines. In some embodiments, core 100 is a prefabricated absorbent core supplied in rolls, spools, or garnishes, which is soft, cost-effective, and has better absorbent properties than other absorbent core designs, including designs having a mixture of fluff pulp and SAP.

[0159] In some embodiments, the ratio of SAP to BNW in the fibrous structure 106 is 3:1 to 15:1 or 5:1 to 10:1 by weight. In some embodiments, the ratio of SAP to fluff in the pulp layer 130 is 1:10 to 2:1 or 5:10 to 1:1 by weight.

[0160] In some embodiments, the fibrous structural sections 106a to 106d include a bulky nonwoven fabric basis weight in the range of approximately 30 to 120 gsm, or 50 to 100 gsm, or 60 to 80 gsm, an SAP basis weight of 150 to 800 gsm, or 200 to 700 gsm, or 300 to 600 gsm, or 400 to 600 gsm, and an adhesive basis weight of 0 to 25 gsm, or 1 to 20 gsm, or 5 to 15 gsm, or 10 to 12 gsm.

[0161] Although the use of adhesives has been described herein, in some embodiments the use of adhesives may be replaced by ultrasonic bonding.

[0162] In some embodiments, the core 100 includes wing sections that define lateral margins on both sides of the core 100. For example, referring to Figure 9A, the wing sections may be raised sections 106a and 106d of a fibrous structure. Each wing section may have a lateral width equal to or greater than 20% of the total width of the core composite 100, such as 20–40%, 25–35%, or 27.5–32.5%, when the core 100 is in a flat configuration. In some embodiments, each intermediate section of the core 100, for example, sections of a fibrous structure positioned between the raised sections 106a and 106d (i.e., sections 106b and 106c), may have a lateral width equal to or less than 50% of the total width of the core composite 100, such as 10–50%, 20–40%, or 30–35%, when the core 100 is in a flat configuration. In some embodiments, the wing sections provide an outer boundary that functions as a lateral margin of the core 100. In some embodiments, the core 100 is fixed to a structural layer (e.g., a back sheet 202) along a bond line 300 that coincides with folds 126a and 126c adjacent to the inner boundary of the wing section. In some such embodiments, fibrous structural sections (i.e., fibrous structural sections 106b and 106c) positioned inside the bond line 300 are free from the structural layer and movable relative to the structural layer.

[0163] In some embodiments, the absorbent cores disclosed herein provide a relatively thin but highly absorbent absorbent core configuration. In contrast to typical fluff / SAP diapers which include a thick fluff layer with a high basis weight, the absorbent cores disclosed herein may include a laminate of relatively thin layered materials including a pulp layer with a low basis weight.

[0164] The fibrous structure can serve to suppress the movement of SAP within the core during the manufacturing, packaging, and wear of the core and articles containing the core. SAP movement can be suppressed at all stages of the product lifecycle. Dry SAP can be immobilized by entanglement with the nonwoven fibers of the BNW and in combination with any adhesives / adhesives present in the nonwoven fabric. Wet SAP can be immobilized by entanglement with the z-direction fibers of the BNW.

[0165] In some such embodiments, the absorbent cores disclosed herein are prefabricated cores that provide a combination of sufficient softness, thinness, absorbency, wet-and-dry integrity, and SAP immobilization. The pulp layer of the lower absorbent core configuration provides a flat and soft appearance that is aesthetically and visually advantageous, along with a soft touch, which can be advantageous for consumers when selecting a product. On the other hand, the upper absorbent core configuration provides a wavy appearance that visually indicates absorbency. Similarly, the upper absorbent core configuration provides the majority of the absorbency of the core disclosed herein. In particular, the SAP contained within the fiber mesh provides the majority of the absorbency of the core disclosed herein and allows the fiber mesh to remain relatively dry. Because the fiber mesh remains relatively dry, the structural integrity of the fiber mesh is maintained, and the core can be dynamically folded and unfolded during use.

[0166] In some embodiments, the use of channels, combined with the strategic positioning of the absorbent core within the article, facilitates the maintenance of a favorable distribution of SAP within the core while optimizing the core's thickness. The fibrous network of the fibrous structure exhibits wet integration without being burdened with fluid retention functions. The SAP contained within the fibrous network can be prevented from moving by adhesives or the like.

[0167] The above description is provided for illustrative and explanatory purposes only. These descriptions are not intended to limit the scope to any specific absorbent core composites and structures or articles, apparatus, and processes that disclose the present invention or aspects thereof. Various aspects of the present invention are directed to applications other than diapers and training pants. The described absorbent core structures can also be incorporated into or combined with other clothing, textiles, fabrics, etc., or combinations thereof. The described absorbent core structures can incorporate different components. Furthermore, the described absorbent core structures may also refer to the substrate (e.g., composite sheet) of such core composites before such absorbent core structures are individualized (as separate absorbent core structures) and incorporated into disposable absorbent articles. These and other variations relating to the present invention will be apparent to those skilled in the art of the relevant consumer goods technology to which the present invention is provided. Accordingly, variations and modifications in accordance with the above teachings and the skills and knowledge of the relevant art fall within the scope of the present invention. The embodiments described and illustrated herein further illustrate the best mode for carrying out the disclosure of the present invention and are intended to enable other persons skilled in the art to utilize the disclosure and other embodiments of the present invention to make various modifications required by a particular use or application of the disclosure of the present invention. [Explanation of symbols]

[0168] 100 Absorbent core composite 108 Horizontal center line 110 Longitudinal centerline 116 Upper nonwoven sheet 130 Lower fibrous structure

Claims

1. A method for making absorbent articles, A step of providing a fibrous structure comprising at least one nonwoven fabric layer having an exposed first surface and an exposed second surface, A step of passing a forced airflow containing an absorbent material over and through the first surface of the fibrous structure, wherein at least a portion of the absorbent material is trapped within the nonwoven fabric between the first surface and the second surface, and at least a portion of the absorbent material passes through the second surface and exits the fibrous structure; Includes, The step of passing the absorbent material through a forced airflow includes filtering at least some of the absorbent material through the nonwoven fabric, at least partially, such that a gradient distribution of particle size of the absorbent material is formed within the nonwoven fabric between the first surface and the second surface, wherein the gradient distribution of particle size of the absorbent material within the nonwoven fabric is such that absorbent material with larger particle size is positioned closer to the first surface and absorbent material with smaller particle size is positioned closer to the second surface.

2. The method according to claim 1, further comprising the step of making the nonwoven fabric adhesive.

3. The method according to 2, characterized in that the adhesiveization step includes a step of heating the nonwoven fabric before or simultaneously with the step of passing the forced airflow over and through the nonwoven fabric.

4. The method according to claim 3, characterized in that the nonwoven fabric has a reduced bulk fiber density after the heating step.

5. The aforementioned nonwoven fabric comprises a two-component fiber including a sheath and a core. The sheath has a lower softening temperature than the core, The heating step softens the sheath of the two-component fiber, At least a portion of the absorbent material adheres to the softened sheath when the forced airflow passes over and through the nonwoven fabric. The method according to feature 3.

6. The method according to claim 2, characterized in that the step of adhesiveization includes a step of incorporating an adhesive into the nonwoven fabric.

7. The method according to 6, characterized in that the adhesive is incorporated by spraying the adhesive onto and at least partially through the nonwoven fabric.

8. The method according to 7, characterized in that the adhesive is sprayed onto the second surface of the nonwoven fabric.

9. The method according to 6, characterized in that the adhesive is provided within the forced airflow.

10. The method according to 6, characterized in that the adhesive is dispersed within the nonwoven fabric with a concentration gradient such that the higher the concentration of the adhesive, the closer it is positioned to the second surface of the nonwoven fabric than to the first surface of the nonwoven fabric.

11. The method according to claim 1, characterized in that the nonwoven fabric has a gradient density such that the density of the nonwoven fabric on the first surface is lower than the density of the nonwoven fabric on the second surface.

12. The method according to claim 1, further comprising the step of filtering absorbent material granules through the nonwoven fabric.

13. The method according to 12, further comprising the step of recovering the absorbent material granules and combining the absorbent material granules with pulp or fluff.

14. The method according to claim 1, further comprising the step of increasing the bulk of the nonwoven fabric at least on the first surface, before or simultaneously with the step of passing the forced airflow through the nonwoven fabric.

15. The method according to 14, characterized in that the bulking step includes a step of brushing the nonwoven fabric, a step of heating the nonwoven fabric, or a combination thereof.

16. The method according to claim 1, further comprising the step of densifying the nonwoven fabric on the second surface.

17. The method according to 16, characterized in that the densification step includes a step of irradiating the nonwoven fabric with infrared light on the second surface.

18. The method according to claim 1, characterized in that the forced airflow is recirculated through the nonwoven fabric via a recirculation loop such that the forced airflow and any absorbing material passing through the second surface of the nonwoven fabric flow back onto and through the first surface of the nonwoven fabric.

19. The method according to claim 3, wherein the forced airflow is a heated forced airflow, and the heating step is performed by placing the heated forced airflow on and passing it through the nonwoven fabric.

20. The method according to claim 3, wherein the heating step is performed by an oven or infrared radiation.

21. The method according to claim 1, further comprising the step of passing the forced airflow through the fibrous structure and then separating the fibrous structure into a plurality of separate fibrous structures.

22. A step of bonding a first nonwoven sheet onto a plurality of separate fibrous structures, wherein the plurality of separate fibrous structures are arranged spaced apart in the transverse direction, and a step of bonding the first nonwoven sheet, The steps include: bonding a second nonwoven sheet to the opposite side of the first nonwoven sheet on the plurality of separate fibrous structures, The method according to claim 21, comprising the step of bonding the first nonwoven sheet to a second nonwoven sheet between adjacent, laterally spaced, separate fibrous structures.

23. The method according to claim 22, further comprising the step of positioning the first nonwoven sheet, the second nonwoven sheet, and the plurality of separate fibrous structures inside the chassis, between the back sheet and the top sheet of the chassis.

24. The method according to claim 1, further comprising the step of recovering the absorbent material that has passed through the second surface and emerged from the fibrous structure.

25. The method according to claim 24, comprising the steps of incorporating the recovered absorbent material into the forced airflow and passing the recovered absorbent material again over and through the first surface of the fibrous structure.

26. The method according to claim 1, comprising the step of transporting the fibrous structure along a path that intersects with a chamber, wherein the path of the forced airflow intersects with the path of the fibrous structure within the chamber.

27. ​​The method according to claim 26, wherein the path of the forced airflow is within the chamber and intersects the fibrous path between the inlet and outlet of the chamber.

28. A method for making an absorbent article, A step of providing a fibrous structure comprising at least one nonwoven fabric layer having an exposed first surface and an exposed second surface, A step of passing a forced airflow containing an absorbent material over and through the first surface of the fibrous structure, wherein at least a portion of the absorbent material is trapped within the nonwoven fabric between the first surface and the second surface, and at least a portion of the absorbent material passes through the second surface and exits the fibrous structure; Includes, The method, wherein the step of passing the forced airflow through the nonwoven fabric includes filtering at least a portion of the absorbent material through the nonwoven fabric at least partially, such that the distribution of the absorbent material is formed within the nonwoven fabric between the first surface and the second surface.

29. The method according to claim 28, further comprising the step of making the nonwoven fabric adhesive.

30. The method according to claim 29, wherein the step of adhesiveization includes a step of heating the nonwoven fabric.

31. The method according to claim 28, further comprising the step of filtering absorbent material granules through at least one layer of the nonwoven fabric.

32. The method of claim 28, comprising recirculating the forced airflow to the nonwoven fabric in a recirculation loop such that the forced airflow and the absorbing material passing through the second surface of the at least one layer of the nonwoven fabric flow back onto and through the first surface of the at least one layer of the nonwoven fabric.

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