Absorbent substrate with enhanced liquid intake function

Abstract

Absorbent articles are disclosed that, in one embodiment, can comprise feminine hygiene products. The absorbent articles can include a multi-layer absorbent substrate. The absorbent substrate contains a retention layer comprised of superabsorbent material. The absorbent substrate can also include a top intake layer comprised primarily of polymer synthetic fibers and binder fibers. The top intake layer is to provide strength and integrity. The absorbent substrate is made according to a wetlaid process, such as a foam forming process. Prior to drying the absorbent substrate or bonding the absorbent substrate, a surfactant composition is applied that has been found to dramatically improve fluid intake rates.

Description

[0001] 65119655PCT04 KCX-2169-PCT

[0002] ABSORBENT SUBSTRATE WITH ENHANCED LIQUID INTAKE FUNCTION

[0003] CROSS-REFERENCE TO RELATED APPLICATION

[0004] The present application is related and has right of priority to U.S. Provisional Patent Application No. 63 / 738,064 filed on December 23, 2024, and U.S. Provisional Patent Application No.

[0005] 63 / 738,046 filed on December 23, 2024, which are incorporated by reference in their entireties for all purposes.

[0006] BACKGROUND

[0007] Personal care products, such as diapers, diaper pants, training pants, adult incontinence products, and feminine care products, can include absorbent structures that are intended to provide various functional characteristics. For example, absorbent structures in such products are intended to intake body exudates quickly and distribute the exudates to an absorbent core or body that is capable of storing the exudates and prevent the exudates in the absorbent core from transferring to other layers of the product and / or against the user’s skin or clothing. Personal care products must also be considerate of other user perceived benefits such as comfort and discreteness, which can be impacted by absorbent structure properties such as thickness, stiffness, and weight.

[0008] Absorbent structures can contain a superabsorbent material. Superabsorbent materials can be configured in the form of particles including fibers and are commonly utilized in substrates for increased absorbent capacity.

[0009] In addition to superabsorbent materials, absorbent structures also typically contain fibers in order to provide strength and integrity to the substrate so that the substrate can be handled and manipulated during processing. Fibers can also be used to capture and maintain the superabsorbent material within the structure. Fibers that can be present in the structure for providing strength and integrity include binder fibers. Binder fibers are fibers that, once subjected to an energy source such as heat, flow and bond to other fibers at crossover points. Consequently, binder fibers can significantly increase the strength and integrity of absorbent substrates.

[0010] Fibers contained in absorbent substrates such as binder fibers and synthetic polymer fibers, however, can be hydrophobic and do not absorb liquids. In fact, binder fibers can increase the hydrophobicity of the substrate when subjected to energy sources and bonded to other fibers. When these fibers are present at the surface of the absorbent substrate, the fibers can interfere with the absorbent substrate from quickly absorbing liquids and moving the liquids into the interior of the absorbent substrate. Consequently, when actions are taken to strengthen the toughness and strength65119655PCT04 KCX-2169-PCT

[0011] of the absorbent substrate, the fluid handling and absorbency characteristics of the substrate can be compromised.

[0012] In view of the above, a need currently exists for an absorbent substrate and a method for producing the absorbent substrate that has strength and toughness while also being capable of rapidly absorbing liquids, such as urine and menses. For example, a need exists for an absorbent substrate design that enables the effective transport and retention of fluids, but also has excellent web handling characteristics that allow the absorbent substate to be processed on a commercial machine or line to make absorbent products.

[0013] SUMMARY

[0014] The present disclosure is generally directed to an absorbent substrate in which at least the top surface of the absorbent substrate contains synthetic fibers in an amount sufficient to provide strength, toughness, and integrity. For instance, the top surface of the absorbent substrate can contain binder fibers that form bond sites with other fibers within the structure. In order to improve fluid intake rates, the absorbent substrate is treated with one or more surfactants in controlled amounts and at particular times during the manufacturing process that permits the surfactant in desired concentrations to penetrate an optimum thickness of the substrate for unexpectedly and dramatically increasing intake rates at relatively low surfactant concentrations. In one aspect, the absorbent substrate can comprise a multi-layered material that can include an intake layer, a retention layer, and optionally a distribution layer. The retention layer contains a superabsorbent material in combination with resilient fibers. The intake layer, on the other hand, contains synthetic fibers for strength but is also treated with a surfactant in a manner that provides for excellent fluid handling properties and intake rates.

[0015] In one embodiment, the present disclosure is directed to an absorbent and unitary substrate. The substrate includes an intake layer containing binder fibers and a retention layer containing a superabsorbent material blended with fibers. At least some of the fibers of the intake layer are intermingled with at least some of the fibers of the retention layer. In accordance with the present disclosure, a surfactant composition comprising at least one surfactant has been applied to the intake layer such that the absorbent and unitary substrate displays a Cut Cradle 1stfree fluid of less than about 15 g after a 38 ml insult. For instance, the absorbent and unitary substrate can display a Cut Cradle 1stfree fluid of less than about 14 g, such as less than about 13 g, such as less than about 12 g, such as less than about 11 g, such as less than about 10 g, such as less than about 9 g, such as less than about 8 g after a 38 ml insult. The absorbent and unitary substrate can display a Cut Cradle 2ndfree fluid of less than about 4 g, such as less than about 3.5 g, such as less than about 3 g, such65119655PCT04 KCX-2169-PCT

[0016] as less than about 2.5 g, such as less than about 2 g, such as less than about 1.5 g, such as less than about 1 g, such as less than about 0.5 g after two 38 ml insults.

[0017] The absorbent and unitary substrate can also display a Cut Cradle 1st free fluid of less than about 32 g, such as less than about 30 g after a 105 ml insult and a 2nd free fluid of less than 50 g, such as less than about 48 g after two 105 ml insults.

[0018] The absorbent and unitary substrate can display a Closed Cradle 1st intake time of less than about 45 sec, such as less than about 40 sec, such as less than about 38 sec, can display a Closed Cradle 2nd intake time of less than about 150 sec, such as less than about 140 sec, such as less than about 130 sec, can display a Closed Cradle 3rd intake time of less than about 180 sec, such as less than about 170 sec, such as less than about 175 sec, and / or can display a rewet of less than about 0.6 g, such as less than about 0.5 g.

[0019] In one aspect, the absorbent and unitary substrate further includes a distribution layer. The retention layer can be disposed between the intake layer and the distribution layer. The intake layer can comprise the binder fibers combined with polymer synthetic fibers. The intake layer can contain cellulose fibers in an amount less than about 5% by weight and, in one embodiment, can be free of cellulose fibers while still displaying excellent fluid intake rates.

[0020] The surfactant composition is applied to the intake layer during the process of producing the substrate in a manner that enables one or more surfactants to penetrate the thickness of the intake layer. In general, any suitable surfactant can be used. For instance, the surfactant can comprise a nonionic surfactant, an anionic surfactant, or mixtures thereof. In one embodiment, for instance, the surfactant composition contains a nonionic surfactant in combination with an anionic surfactant. The surfactant composition is applied to the intake layer such that one or more surfactants are present in the absorbent and unitary substrate in an amount less than about 1 gsm, such as in an amount less than about 0.8 gsm, such as in an amount less than about 0.6 gsm, such as in an amount less than about 0.4 gsm, and in an amount greater than about 0.05 gsm, such as in an amount greater than about 0.1 gsm, such as in an amount greater than about 0.15 gsm, such as in an amount greater than about 0.2 gsm.

[0021] In one embodiment, the absorbent and unitary substrate comprises a foam formed nonwoven material. The substrate can have a basis weight of from about 250 gsm to about 1 ,300 gsm. The superabsorbent material can be contained in the retention layer at a basis weight of generally greater than about 150 gsm, such as greater than about 180 gsm, such as greater than about 190 gsm, and less than about 700 gsm, such as less than about 500 gsm.65119655PCT04 KCX-2169-PCT

[0022] In an alternative embodiment, the present disclosure is directed to an absorbent and unitary substrate that contains an intake layer, optionally a distribution layer, and a retention layer positioned between the intake layer and the distribution layer. The intake layer can comprise binder fibers alone or in combination with synthetic polymer fibers. The retention layer can contain a superabsorbent material in combination with fibers, such as crosslinked cellulose fibers. A surfactant composition comprising at least one surfactant is present at least within the intake layer. The surfactant composition is applied such that, when tested according to the Surfactant Penetration Quantification Test, an element, such as sulfur, identifying the presence of a surfactant is present over at least 10% of the thickness of the intake layer, such as at least over 15% of the thickness of the intake layer, such as at least over about 20% of the thickness of the intake layer, such as at least over about 25% of the thickness of the intake layer, such as at least over about 30% of the thickness of the intake layer, such as at least over about 35% of the thickness of the intake layer, such as at least over about 40% of the thickness of the intake layer, such as at least over about 45% of the thickness of the intake layer, such as at least over about 50% of the thickness of the intake layer, such as at least over about 55% of the thickness of the intake layer, such as at least over about 60% of the thickness of the intake layer.

[0023] In one aspect, the surfactant can be present over the entire thickness of the substrate, but can be more concentrated in the top half of the substrate For instance, the surfactant composition can be applied such that, when tested according to the Surfactant Penetration Quantification Test, at least about 42 %, such as at least about 44%, such as at least about 46% by weight of the surfactant remains in the top 50% of the thickness of the substrate.

[0024] The absorbent substrate of the present disclosure can be incorporated into any suitable absorbent article or personal care product. In one particular embodiment, the absorbent article can comprise a feminine care product, such as a feminine care pad.

[0025] Other features and aspects of the present disclosure are discussed in greater detail below.

[0026] BRIEF DESCRIPTION OF THE DRAWINGS

[0027] A full and enabling disclosure of the present disclosure is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:

[0028] FIG. 1 is a plan view with cutaway portions of one embodiment of an absorbent article made in accordance with the present disclosure;

[0029] FIG. 2 is a side plan view of an exemplary multi-layer absorbent material including three layers according to one embodiment of the present disclosure;

[0030] FIG. 3 is a process schematic of an exemplary apparatus and associated method for forming a multi-layer absorbent material;65119655PCT04 KCX-2169-PCT

[0031] FIG. 4 is a detailed view of the headbox, headbox inputs, and resultant slurry from the headbox of FIG. 4;

[0032] FIG. 5 is a perspective view of the apparatus used to conduct the Cut Cradle Test as described below;

[0033] FIG. 6 is a perspective view of the apparatus used to conduct the Closed Cradle Test as described below;

[0034] FIG. 7 is a perspective view of the top of the apparatus used to conduct the Closed Cradle Test as described below; and

[0035] FIG. 8 is a perspective view of the saddle used to conduct the Closed Cradle Test as described below.

[0036] Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention.

[0037] DEFINITIONS

[0038] As used herein, the term “foam formed product” means a product formed from a suspension including a mixture of a solid, a liquid, and dispersed gas bubbles.

[0039] As used herein, the term “foam forming process” means a process for manufacturing a product involving a suspension including a mixture of a solid, a liquid, and dispersed gas bubbles.

[0040] As used herein, the term “foaming fluid” means any one or more known fluids compatible with the other components in the foam forming process. Suitable foaming fluids include, but are not limited to, water.

[0041] As used herein, the term “foam half life” means the time elapsed until the half of the initial frothed foam mass reverts to liquid water.

[0042] As used herein, the term “layer” refers to a structure that provides an area of a substrate in a height direction of the substrate that is comprised of similar components and structure. There may be some mixing of fiber between adjacent layers.

[0043] As used herein, the term "nonwoven web" means a web having a structure of individual fibers or threads which are interlaid, but not in an identifiable manner as in a knitted web.

[0044] As used herein, unless expressly indicated otherwise, when used in relation to material compositions the terms "percent", “%”, "weight percent”, or "percent by weight" each refer to the quantity by weight of a component as a percentage of the total except as whether expressly noted otherwise.

[0045] The term “absorbent article” refers herein to an article intended and / or adapted to be placed against or in proximity to the body (i.e., contiguous with the body) of the wearer to absorb and contain65119655PCT04 KCX-2169-PCT

[0046] various liquid, solid, and semi-solid exudates discharged from the body. Examples include, but are not limited to, diapers, diaper pants, training pants, youth pants, swim pants, feminine hygiene products, including, but not limited to, menstrual pads or pants, incontinence products, medical garments, surgical pads and bandages, and so forth.

[0047] The term "superabsorbent material" as used herein refers to water-swellable, water-insoluble organic or inorganic materials including superabsorbent polymers and superabsorbent polymer compositions capable, under the most favorable conditions, of absorbing at least about 10 times their weight, or at least about 15 times their weight, or at least about 25 times their weight in an aqueous solution containing 0.9 weight percent sodium chloride.

[0048] The term "machine direction" as used herein refers to the direction of travel of the forming surface onto which fibers are deposited during formation of a nonwoven web.

[0049] The term "cross-machine direction" as used herein refers to the direction which is perpendicular to both the machine direction and the height direction defined above.

[0050] The term "pulp" as used herein refers to fibers from natural sources such as woody and non-woody plants. Woody plants include, for example, deciduous and coniferous trees. Non-woody plants include, for example, cotton, flax, esparto grass, milkweed, straw, jute, hemp, and bagasse. Pulp fibers can include hardwood fibers, softwood fibers, and mixtures thereof.

[0051] The term "average fiber length" as used herein refers to an average length of fibers, fiber bundles and / or fiber-like materials determined by measurement utilizing microscopic techniques. A sample of at least 20 randomly selected fibers is collected. For example, the fibers can be separated from a liquid suspension of fibers. The fibers are set up on a microscope slide prepared to suspend the fibers in water. A tinting dye is added to the suspended fibers to color cellulose-containing fibers so they may be distinguished or separated from synthetic fibers. The slide is placed under a Fisher Stereomaster II Microscope-S19642 / S 19643 Series. Measurements of 20 fibers in the sample are made at 20X linear magnification utilizing a 0-20 mils scale and an average length, minimum and maximum length, and a deviation or coefficient of variation are calculated. In some cases, the average fiber length will be calculated as a weighted average length of fibers (e.g., fibers, fiber bundles, fiberlike materials) determined by equipment such as, for example, a Kajaani fiber analyzer Model No. FS-200, available from Kajaani Oy Electronics, Kajaani, Finland. According to a standard test procedure, a sample is treated with a macerating liquid to ensure that no fiber bundles or shives are present. Each sample is disintegrated into hot water and diluted to an approximately 0.001% suspension. Individual test samples are drawn in approximately 50 to 100 ml portions from the dilute suspension when tested using the standard Kajaani fiber analysis test procedure. The weighted average fiber65119655PCT04 KCX-2169-PCT

[0052] length may be an arithmetic average, a length weighted average or a weight weighted average and may be expressed by the following equation:

[0053]

[0054] where

[0055] k=maximum fiber length

[0056] xrfiber length

[0057] n(=number of fibers having length xi

[0058] n=total number of fibers measured.

[0059] One characteristic of the average fiber length data measured by the Kajaani fiber analyzer is that it does not discriminate between different types of fibers. Thus, the average length can represent an average based on lengths of all different types of fibers in the sample or of a single fiber type.

[0060] As used herein the term "staple fibers" means discontinuous fibers made from synthetic polymers or regenerated cellulose, such as polypropylene, polyester, post consumer recycle (PCR) fibers, polyester, nylon, viscose, rayon, and the like, and those not hydrophilic may be treated to be hydrophilic. Staple fibers may be cut fibers or the like. Staple fibers can have cross-sections that are round, bicomponent, multicomponent, shaped, hollow, or the like.

[0061] The term “plied” or “bonded” or “coupled” refers herein to the joining, adhering, connecting, attaching, or the like, of two elements. Two elements will be considered plied, bonded or coupled together when they are joined, adhered, connected, attached, or the like, directly to one another or indirectly to one another, such as when each is directly bonded to intermediate elements. The plying, bonding or coupling of one element to another can occur via continuous or intermittent bonds.

[0062] As used herein, “binder fibers” are fibers that can bond to other fibers in a substrate using chemical, mechanical, or thermal means. The binder fibers may comprise thermally bondable fibers that, when heated, form thermal bonds with other fibers at their point of intersection. In one aspect, the binder fibers include a surface polymer having a lower melting temperature. For instance, the binder fibers can be made from a polymer, such as a polyolefin, having a melting temperature of less than 200°C, such as less than 180°C, such as less than 160°C, such as less than 140°C, such as less than 120°C, such as less than 100°C, and greater than 80°C, such as greater than 90°C. In one aspect, the binder fibers comprise conjugate fibers, such as bicomponent fibers. The conjugate fibers can have a core and sheath structure, including a core polymer surrounded by a sheath polymer. The65119655PCT04 KCX-2169-PCT

[0063] core polymer can have a higher melting temperature than the sheath polymer. The core polymer can be selected for its strength and high melting point and the sheath polymer can be made from a polymer selected for its lower melting temperature. The core polymer, for instance, can have a melting temperature higher than the sheath polymer. In this manner, the sheath polymer, when subjected to heat, melts and bonds to other fibers within the web at intersecting points. The core polymer, however, allows the bicomponent binder fiber to retain its shape and provide strength.

[0064] As used herein, “synthetic polymer fibers” refers to fibers made from polymers that are not binder fibers. Synthetic polymer fibers can include polyester fibers, such as fibers made from a polyethylene terephthalate polymer. Other polymer synthetic fibers include polyolefin fibers, such as polyethylene fibers, polypropylene fibers, and fibers made from copolymers of the above.

[0065] As used herein, “resilient fibers” refers to fibrous materials that bend and deform under an applied load but largely recover their shape to their original dimensions after removal of the applied load. These fibers when combined with other fibers and materials and are incorporated in an absorbent composite, enable the composite material to largely recover its shape when a load is applied and them removed.

[0066] Examples of resilient fibres include both natural and synthetic fibers. Examples of natural cellulosic fibers would include crosslinked celuulosic fibers, regenerated cellulosic fibers, and natural cellulosic fibers such as coconut coir fibers. Examples of resilient synthetic fibers include staple fibers of various types. The staple fibers could be made from many different polymers including polyolefins, polyesters, nylons, and acrylics. The synthetic staple fibers could be hydrophilic or hydrophobic and could be treated suitably to derive the desired level of wettability. The staple fibers can have crosssections that are circular, bicomponent such as side-by-side, concentric, or eccentric, shaped with different cross sections, hollow, or other types.

[0067] The binder fibers can be used together with other fibers and enable the structure to be bonded using themal bonding, mechanical bonding, or chemical bonding. The eccentric bicomponent fibers can also change their shape and contribute to the resilience of the structure by creating shapes that are more resistant to deformation under load. Crimping and curling of the fibers can also be used to impart a shape and geometry to the fiber that would be more resistant to deformation under an applied load and thereby create a more resilient fiber.

[0068] As used herein, thickness measurements utilize a standard bulk tester with clear, cast acrylic foot that provides 0.05 psi (see for instance US Patent No. 8,546,638 which is incorporated herein by reference).65119655PCT04 KCX-2169-PCT

[0069] As used herein, the Horizontal Side Compression Test is performed as follows with reference to Figures 7 A and 7B of WO 2023 / 164126 which is incorporated herein by reference. During the test, the absorbent material is compressed horizontally. The test is designed to compress an absorbent product in the crotch area to measure the resiliency, flexibility or stiffness, and width recovery of the crotch area of the product.

[0070] The test protocol has 10 compression cycles of a dry product followed by 10 compression cycles of wet product. A relevant test fluid, saline or defibrinated swine blood, is applied to the product following the dry compression cycles. This test is performed with the product in a horizontal position to represent the typical user position of active wear. Additionally, a horizontal placement facilitates the ability to insult the products with the test fluids without needing to remove the test sample from the apparatus.

[0071] The product may be tested with or without flaps and / or with or without wings. Test outputs include energy, resiliency, and width recovery.

[0072] A CRE (Constant Rate of Extension) type of tensile tester with data acquisition unit and data acquisition program capable of collecting data such as Instron 3343 system with Bluehill program or MTS Insight 1EL system with TestWorks 4.0 is used during the test. The product being tested is oriented horizontally in the test jaws.

[0073] Unless otherwise indicated, defibrinated swine blood @ 35% red blood cells is used which is available from Cocalico Biologicals, Inc.

[0074] The product should be conditioned for 4 hours in TAPPI conditions prior to testing. The center point and insult location of each product should be marked. For incontinence and menstrual pads, measure the length of the entire product and divide by 2. This value will represent the center point. Put a vertical mark at the center point. The center point will be the insult location.

[0075] The Test is conducted by warming up the tensile tester according to the manufacturer's manual. Next, verify the appropriate load cell is in the tensile tester, which should be selected from either a 50 Newton or 100 Newton maximum, depending on the peak force value of the sample being tested, such that the majority of peak load values fall between 5-95% of the load cell's full scale value. For purposes of the samples tested herein, a 100 Newton load cell is used. In this test, both edges of the absorbent material are clamped between top and bottom grips of the tensile tester with the center of the sample aligned with the center of the grips and the sample centered between the grips. The computer is turned on and the software menu selection is followed. The load cell for the tensile tester is calibrated according to the manufacturer's instructions. The test conditions are as follows.65119655PCT04 KCX-2169-PCT

[0076] Cross Head Speed 508 + / - 5mm / min

[0077] Gauge Length 90mm (initial compression plate separation distance)

[0078] End Compression Distance 30mm

[0079] Load Unit Newton

[0080] Full Scale Load 100 Newton (use an appropriate load cell for the product being tested so that the test value falls between 5% and 95% of the full-scale load)

[0081] Sample materials can be placed in product form by using the absorbent product sample. Ensure the lanyard thread is in and remains in the wheel guides, one in the front and two wheel guides in the back of the tester (see Figures 7A and 7B from WO 2023 / 164126). A piece of masking tape can be placed close to one of the back wheels of the tester without touching the lanyard to prevent the lanyard moving out of the wheel when the crosshead returns to its start position. Two hanging weights are attached to the wheel guide at the far back of the testing unit. Orient the weights up-side down to shorten the hook length such that the weights do not touch the frame.

[0082] With the lanyard attached to a hook below the load cell, adjust the crosshead so the resultant force exerted by the lanyard is less than 0.5 grams. Measure and then record the initial width of the specimen in the mid-crotch area. Then, zero the crosshead channel and start the test run.

[0083] At the end of the 10thcycle in the dry condition, the test will pause with fixture open at the initial plate compression separation distance. Add a single insult of test fluid at the insult location (5 mL). Run 10 more cycles.

[0084] At the conclusion of all cycles, measure and record the final width of the specimen in the midcrotch area. A data report is generated that provides the cycle 1 energy, cycle 10 energy and cycle 20 energy (gf*cm). The width recovery % is measured as final width at end of all cycles divided by the initial width, multiplied by 100.

[0085] As used herein, the “Cut Cradle (free fluid) Test” is as follows. The test simulates the “on-body” position angle while measuring free fluid within products after loadings in absorbent articles, such as diapers, training pants, and adult incontinence products.

[0086] 1.0 EQUIPMENT AND SUPPLIES

[0087] 1.1 Incline board (metallic) set to an angle of incline of 62°.

[0088] 1.2 Magnets with felt base weighing approximately 33 grams to secure product to board.

[0089] 1.3 Mesh screen, approximately 11.5” x 4.5,” to separate saline from loose superabsorbent material (“SAM”).

[0090] 1.4 Electro-balance readable to at least 0.01 grams.65119655PCT04 KCX-2169-PCT

[0091] 1.5 Fluid dispensing pump capable of dispensing fluid at a constant volume while maintaining a specified flow rate, such as Cole-Palmer peristaltic pump (P / N 07551 - 20) and pump head (P / N 77201-60). A foot pedal can be used in order to initiate pump.

[0092] 1.5.1 Pump tubing, clear, to allow visibility to air pockets within the tubing, such as Masterflex clear Tubing L / S 14, L / S 16, L / S 25 or L / S 17.

[0093] 1 .5.2 Standoff fitting with an exit diameter of 0.125.”

[0094] 1.6 Saline solution, 0.9 ± 0.005% (w / w) aqueous isotonic saline maintained at a temperature of 98.6 ± 1.8 °F / 37 ± 1 °C.

[0095] 1.7 Countdown timers, readable to 1 second.

[0096] 1.8 Tray with a minimum capacity of 300 mL of fluid, not less than 6” wide.

[0097] 1.9 Lab jacks large enough to hold a tray and a screen under the edge of the incline board.

[0098] 1.10 Scissors capable of cutting completely through product.

[0099] 2.0 SAMPLE PREPARATION

[0100] 2.1 Weigh the product to the nearest 0.01 grams and record.

[0101] 2.2 Mark the center of the whole product (length) on the body side of the product and then draw a line across the center of the product.

[0102] 2.2.1 Mark the insult location 95 mm from the center.

[0103] 2.3 Using a cut glove, carefully cut the product completely from one side to the other through the center line. Hold the product carefully to minimize SAM loss during cutting.

[0104] 2.3.1 Discard the back portion of the product.

[0105] 2.4 Weigh the front half of the product to the nearest 0.01 grams and record.

[0106] 3.0 SETUP PROCEDURE

[0107] 3.1 Set one countdown timer to 10 minutes and set another countdown timer to 30 seconds.

[0108] 3.2 Place the product onto the incline board and secure using four magnets (Figure 5), one at each of the four corners of the specimen. Be sure to align the cut edge of the specimen with the bottom edge of the insult board. Do not stretch the edge taut as this could inhibit fluid movement. As shown in Fig. 5, the setup includes an inclined board 300. A specimen 302 to be tested is held on the board 300 by the magnets 304. A65119655PCT04 KCX-2169-PCT

[0109] tray 306 covered by a screen 308 are placed to catch free fluid. The tray 306 may be held by a jack 310.

[0110] 3.3 Weigh a clean, dry tray and record the weight. Place the pre-weighed tray (Figure 5) directly below and centered under the open edge of the product to catch free fluid. 3.4 Weigh a clean, dry mesh screen and record the weight. Place the screen into the slot above the tray to catch any loose SAM that may fall out of the cut edge of the product.

[0111] 4.0 TEST PROCEDURE

[0112] 4.1 Place the standoff fitting against the product (without applying pressure) so that the tip of the opening is at least 3 mm from the surface and perpendicular to the specimen at the target location.

[0113] 4.2 Start the pump to dispense the saline loading; be sure any fluid exiting the specimen is collected in the catch tray beneath the specimen. The flow rate is 8 ml / second. The test fluid amount is 38 ml per insult or 105 ml per insult.

[0114] 4.3 After the insult is complete, start the 10-minute timer.

[0115] 4.4 Weigh the screen with any SAM that may have fallen out of the product while insulting and record the weight to the nearest 0.01 grams as “1stInsult SAM and Screen Weight.”

[0116] 4.4.1 After removing the 1 st Insult screen and tray, place another screen and tray below the product to catch anything that may fall out during the 10-minute wait.

[0117] 4.4.2 Place the screen with SAM onto the balance and record the weight to the nearest 0.01 grams.

[0118] 4.4.3 If any SAM falls out of the cut edge of the specimen during the 10-minute wait, weigh the SAM and record the weight to the nearest 0.01 grams in a comment on the data sheet.

[0119] 4.4.4 Specimens yielding SAM loss amounts weighing >2 grams during the 1st insult and the 10-minute wait are considered a FAIL and testing for that specimen should be aborted. Retest with a new specimen.

[0120] 4.4.5 Dispose of any SAM on the screen into the garbage.

[0121] 4.5 Weigh any free fluid collected in the tray.

[0122] 4.5.1 Place the tray with fluid onto the balance and record the weight to the nearest 0.01 grams as “1stInsult Free Fluid and Tray Weight”.

[0123] 4.6 Slowly pour the fluid back into specimen at or near the insult location.65119655PCT04 KCX-2169-PCT

[0124] 4.6.1 If there is free fluid after pouring the saline back repeat 4.6.

[0125] 4.6.2 If there is free fluid after the third attempt, record the weight of the free fluid remaining in the tray in the comments and discard.

[0126] 4.7 Replace the tray and screen as described in steps 4.5 and 4.6.

[0127] 4.8 After the 10-minute wait, repeat steps 4.1 and 4.2 for a second insult.

[0128] 4.9 After the insult is complete, start the 30-second timer.

[0129] 4.9.1 After the 30-second wait, weigh the wet front half of the specimen and record to the nearest 0.01 grams and discard the tested specimen.

[0130] 4.10 Weigh the screen with any SAM that may have fallen out of the product while insulting and record the weight to the nearest 0.01 grams as "2ndInsult SAM and Screen Weight”.

[0131] 4.11 Weigh any free fluid collected in the tray.

[0132] 4.11.1 Place the tray with fluid onto the balance and record the weight to the nearest 0.01 grams as “2nd Insult Free Fluid and Tray Weight”.

[0133] From the above procedure, a 1stFree Fluid amount and a 2ndFree Fluid amount can be determined in grams.

[0134] As used herein, the “tensile strength” of a material defined as the peak load achieved during the test, is measured in both the Machine Direction (MD) and the cross-machine direction (CMD) using an Instron model 3343 tensile testing device running an Instron Series IX software module Rev. 1.16 with a + / -1 kN load cell. The initial jaw separation distance (“Gauge length”) is set at 75 millimeters and the crosshead speed is set at 300 millimeters per minute. Samples are cut to 50 mm width by 300 mm length in the machine direction (MD) and each tensile strength test result reported is the average of two samples per code. Samples are evaluated at room temperature (about 20 degrees Celsius). Excess material is allowed to drape out the ends and sides of the apparatus. Cross machine direction (CMD) strengths and extensions are also measured and generally the CMD strengths are about one half to one fifth of MD strength and CMD extensions at peak load are about two to three times higher than in the MD direction. (The CMD samples are cut with the long dimension being taken in the CMD.) MD strengths are reported in Newtons per 50 mm width of material. (Results are shown in Tables 1 and 2) MD extensions for the material at peak load are reported as the percentage of the initial gauge length (initial jaw separation).

[0135] As used herein, the “Surfactant Penetration Quantification Test Method” is as follows. The Surfactant Penetration Quantification Test Method determines the presence, concentration and distribution of an atom, such as sulfur, that is associated with the surfactant applied to the absorbent65119655PCT04 KCX-2169-PCT

[0136] substrate. The test is to determine penetration of the surfactant into the substrate. The method uses SEM microscopy imaging of the thickness of the substrate and subsequent image analysis protocol. Samples are cryo-cross sectioned then mounted in the Y plane to a SEM sample stub for Elemental analysis.

[0137] Instrumentation

[0138] • SEM: JEOL JSM-IT700HR

[0139] o Back Scatter Detector

[0140] o 20KV Spot Size 70

[0141] • JEOL EX-74600u4l20 Elemental X-ray detector.

[0142] o Analysis Conditions

[0143] ■ Elemental Map

[0144] ■ Resolution 4096x3072

[0145] ■ Dwell time 0.5ms

[0146] ■ 1 acquired frame.

[0147] Image Analysis Methodology

[0148] Platform: Leica Microsystems QWIN

[0149] Image Analysis Algorithm: Name - Cross-section In-plane Slicer- 2

[0150] NAME: Cross-section In-plane Slicer - 2

[0151] PURPOSE: Measures internal properties at various depths via a marching bar 'slicer' CONDITIONS: EDS images detecting sulfur

[0152] Open File (C:\Data\05168 - Wallajapet\data.xls, channel #1)

[0153] ACQOUTPUT = 0

[0154] SET UP

[0155] Image frame (x 0, y 0, Width 578, Height 560)

[0156] Measure frame (x 31 , y 61 , Width 516, Height 498)

[0157] Enter Results Header

[0158] File Results Header (channel #1)

[0159] File Line (channel #1)

[0160] File ("Z-Position", channel #1, field width: 9, left justified)

[0161] File ("Area (sq. urn)", channel #1, field width: 18, left justified)

[0162] File ("% Area", channel #1 , field width: 10, left justified)65119655PCT04 KCX-2169-PCT

[0163] File Line (channel #1)

[0164] CALVALUE = 9.01

[0165] Calibration (Local)

[0166] SAMPLE REPLICATE LOOP

[0167] For (REPLICATE = 1 to 1, step 1)

[0168] ACQUIRE AND DETECT IMAGE

[0169] Read image [PAUSE] (from file C:\lmages\05168 - WallajapetXAfter Drying image.jpg into ColourO)

[0170] Colour Detect (HSI: 0-103, 149-255, 15-255, from ColourO into BinaryO)

[0171] SECTION SLICE LOOP GRAPHNX = 1

[0172] GRAPHNY = 1

[0173] GRAPHWID = 510

[0174] GRAPHHGHT = 4

[0175] Calibrate (CALVALUE CALUNITS$ per pixel)

[0176] GRAPHORGX = 32

[0177] GRAPHORGY = 105

[0178] GRAPHTHIK = 1

[0179] GRAPHORNT = O

[0180] GRAPHOUT = 19

[0181] For (SECTION = 1 to 146, step 1)

[0182] ZDEPTH = (SECTION-1) * CALVALUE*4

[0183] File (ZDEPTH, channel #1, field width: 9, left justified, 1 digit after '.')

[0184] Clear Feature Histogram #1

[0185] Clear Feature Histogram #2

[0186] Graphics (Grid, GRAPHNX x GRAPHNY Lines, Grid Size GRAPHWID x GRAPHHGHT, Origin GRAPHORGX x GRAPHORGY, Thickness GRAPHTHIK, Orientation GRAPHORNT, to GRAPHOUT Cleared)

[0187] GRAPHORGY = GRAPHORGY+465119655PCT04 KCX-2169-PCT

[0188] Binary Logical (C = A AND B: C Binary2, A Binary19, B BinaryO)

[0189] FIELD MEASUREMENTS

[0190] -- Frame area measurement

[0191] MFLDIMAGE = 19

[0192] Measure field (plane MFLDIMAGE, into FLDRESULTS (1), statistics into FLDSTATS (7,1)) Selected parameters: Area

[0193] FRAMEAREA = FLDRESULTS (1)

[0194] - Material Area & % Area Measurement / Calculation

[0195] MFLDIMAGE = 2

[0196] Measure field (plane MFLDIMAGE, into FLDRESULTS (1), statistics into FLDSTATS (7,1)) Selected parameters: Area

[0197] AREA = FLDRESULTS (1)

[0198] PERCAREA = AREA / FRAMEAREA*100

[0199] File (AREA, channel #1, 2 digits after '.')

[0200] File (PERCAREA, channel #1 , 1 digit after '.')

[0201] File Line (channel #1)

[0202] Next (SECTION)

[0203] File Line (channel #1)

[0204] File Line (channel #1)

[0205] File Line (channel #1)

[0206] File Line (channel #1)

[0207] Next (REPLICATE)

[0208] Close File (channel #1)

[0209] END

[0210] Use of the above algorithm can determine atom concentrations, such as sulfur concentrations, across the samples analyzed. Results show Z-position (micron), area (sq. micron), and percent area. Each analysis slice is approximately 36 microns thick.65119655PCT04 KCX-2169-PCT

[0211] As used herein, the “Closed Cradle Test” is as follows. The test method is provided for evaluating fluid intake performance and surface rewet characteristics of an absorbent article under consumer-relevant conditions. The method simulates use conditions by subjecting the article to controlled pressure while the article is held in a curved configuration representative of wear. The method further incorporates machine-direction (MD) and cross-direction (CD) curvature and applies a urine-analog fluid at a defined location, volume, and delivery rate.

[0212] This test method measures the time it takes, in seconds, for a consumer relevant amount of urine-like fluid to enter the absorbent of a product with consumer relevant curvature while under pressure. It also measures the amount of fluid that returns to the surface of the product (rewet), in grams, at the insult location. Rewet is meant to assess the wetness at the surface of the product soon after a urine loss episode.

[0213] The test apparatus comprises:

[0214] 1. A Closed Cradle configured to support an absorbent article in a curved geometry while permitting fluid introduction through a defined port (See FIGS. 6-8).

[0215] 2. A Sling adapted to retain the Closed Cradle during testing; Mfr Model #: 20103840-06 (Apache Inc.) or equivalent (See FIG. 6 and FIG. 7).

[0216] 3 A Saddle positioned on the Closed Cradle and configured to support removable weights (See FIG. 8).

[0217] 4. Weights sufficient to apply a total load that produces an average pressure of approximately 0.25 psi over the article.

[0218] 5. A Fluid Delivery System, including a peristaltic pump, tubing, and a terminal fitting having an outlet diameter of approximately 0.125 inches.

[0219] 6. A Leveling Device to ensure the Closed Cradle is horizontally level during testing.

[0220] 7. A Rewet Assembly, including blotter paper and a cylindrical rewet weight (1096 grams, 2.4 inches in diameter, brass) configured to apply approximately 0.5 psi to the blotter paper.

[0221] 8 Measurement Devices, including a balance (readable to 0.001 grams) for article and blotter paper mass, balance readable to at least 0.01 grams and a max weight capacity of at least 500 grams for product weights, a thickness tester, and timing devices.

[0222] 9. Blotter Paper such as “Verigood” Grade, 100 lb. blotter paper, cut to 88 by 300 ± 13 mm (3.5” by 12” ± 0.5”).

[0223] 10. Disk Weights, 6 - 2.5 lb. weights per Closed Cradle, placed on the saddle to achieve the desire pressure (0.25 psi).65119655PCT04 KCX-2169-PCT

[0224] The Test Fluid is a urine-analog solution is employed, comprising an aqueous saline solution having surface tension adjusted to 0.9 ± 0.005% (w / w). 0.1 g / L Sodium Taurocholate Hydrate + / - 0.01 g / L. The solution is maintained at a temperature of approximately 37 ± 1 °C prior to and during testing.

[0225] Sample Preparation

[0226] An absorbent article to be tested is conditioned under controlled temperature and humidity prior to testing. More particularly, the product is placed under TAPPI conditions for at least 4 hours prior to testing (TAPPI T 402 sp 08 Standard Conditioning and Testing Atmospheres for Paper, Board, Pulp hand sheets, and Related Products). The article is laid flat without folding, and the longitudinal center of the article is identified. A target insult location is determined as a predefined distance forward of the longitudinal center, based on product type and intended wearer. For female products, the target insult location is 9.5 cm forward from product center. For male products, the target insult location is 20 cm forward from product center.

[0227] The absorbent core is isolated by removing surrounding materials while avoiding damage to the absorbent structure. Articles exhibiting damage are discarded.

[0228] Test Setup

[0229] The Closed Cradle is cleaned and prepared. One fluid introduction port is selected based on the intended orientation of the article, and any unused port is sealed. Hook fasteners are applied to the underside of the Closed Cradle to retain the article at its non-absorbent regions. The absorbent article is mounted onto the Closed Cradle such that the target insult location is centered over the selected port. The article is tensioned to remove slack while avoiding stretching. The Closed Cradle is then placed into the sling as shown in FIG. 6 such that the absorbent core 414 is placed between the sling 412 and the cradle 410.

[0230] The saddle 416 is positioned on the Closed Cradle as shown in FIG. 8, and the cradle is leveled in orthogonal directions. Weights are added incrementally and symmetrically until a total load of approximately 15 pounds is applied, corresponding to an average pressure of approximately 0.25 psi.

[0231] Intake Testing Procedure

[0232] Prior to fluid loading, the dry article mass and thickness at the target insult location are measured and recorded.

[0233] Fluid is delivered through the selected port at a predefined flow rate and total volume corresponding to consumer-relevant usage conditions. In particular, the rate is 3 ml / sec. A single insult is 25 ml for female products with moderate absorbency and 50 ml for all other65119655PCT04 KCX-2169-PCT

[0234] products. Delivery is initiated simultaneously with timing. Fluid is directed along the interior wall of the port rather than directly onto the article surface.

[0235] An intake time is defined as the elapsed time between initiation of fluid delivery and the point at which visible fluid has fully penetrated the surface of the article. Intake time is recorded for each insult. After each insult, a waiting period of 15 minutes is observed prior to subsequent insults.

[0236] Multiple insults may be applied sequentially, each with its own recorded intake time. If fluid runoff occurs or if fluid remains pooled on the surface beyond a predetermined duration, the article is classified as a failure and further testing on that specimen is discontinued.

[0237] Upon completion of the final insult, the weights and saddle are removed, and the article is carefully detached without inversion or additional pressure. Wet article thickness and wet mass are then measured.

[0238] Rewet Measurement

[0239] Rewet testing is conducted on articles that do not exhibit runoff. After a 2 minute delay following the final insult, the article is removed from the closed cradle without being turned upside down and placed flat with the body-facing surface upward and secured to prevent wrinkling.

[0240] Two pre-weighed blotter papers are stacked and positioned over the target insult location. The rewet weight is placed centrally on the blotter papers to apply a pressure of approximately 0.5 psi for 2 minutes.

[0241] Following removal of the weight, the blotter papers are reweighed. Rewet mass is calculated as the difference between wet and dry blotter paper weights, representing fluid transferred from the article to the surface under pressure.

[0242] DETAILED DESCRIPTION

[0243] It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only and is not intended as limiting the broader aspects of the present disclosure.

[0244] The present disclosure is directed to methods and systems that can produce nonwoven substrates. While the present disclosure provides examples of substrates manufactured through foam-forming, it is contemplated that the methods and apparatuses described herein may be utilized to benefit any wet-laid process.65119655PCT04 KCX-2169-PCT

[0245] Each example is provided by way of explanation and is not meant as a limitation. For example, features illustrated or described as part of one embodiment or figure can be used on another embodiment or figure to yield yet another embodiment. It is intended that the present disclosure include such modifications and variations.

[0246] When introducing elements of the present disclosure or the preferred embodiment(s) thereof, the articles “a”, “an", “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. As used herein, the terminology of “first,” “second,” “third”, etc. does not designate a specified order, but is used as a means to differentiate between different occurrences when referring to various features in the present disclosure. Many modifications and variations of the present disclosure can be made without departing from the spirit and scope thereof. Therefore, the exemplary embodiments described herein should not be used to limit the scope of the invention.

[0247] In general, the present disclosure is directed to absorbent structures and / or absorbent articles demonstrating excellent fluid handling properties. In one aspect, for instance, absorbent articles made according to the present disclosure can be capable of not only rapidly absorbing fluids but retaining significant amounts of fluids while remaining relatively thin and flexible. In this manner, absorbent articles made according to the present disclosure can provide supreme comfort to the wearer.

[0248] In the past, many absorbent substrates for absorbent articles were produced through a dry process in order to avoid contacting a superabsorbent material contained in the substrate with moisture during the process that would then require the product to be dried. The use of wetlaid processes to produce absorbent substrates, however, can present various advantages and benefits. For example, when producing an absorbent substrate through a foam forming process, higher throughputs can be achieved without saturating the superabsorbent material with water. Wetlaid absorbent substrates can also be produced in spirally wound rolls that can be unwound and fed into a process for making absorbent articles. Consequently, producing absorbent substrates through a wetlaid process can also produce various efficiencies in downstream processes.

[0249] When producing an absorbent substrate through a wetlaid process, such as a foam forming process, the substrate being formed should have sufficient strength and toughness to withstand the forces that are generated during winding, unwinding, cutting, and manipulation when fed through a process for making absorbent articles. In order to increase strength and toughness, the wetlaid absorbent substrates can contain synthetic polymer fibers including binder fibers. After the absorbent substrate is formed, the substrate is heated such as being fed through a through-air dryer to a65119655PCT04 KCX-2169-PCT

[0250] temperature sufficient for the binder fibers to become activated and form bond sites within the structure where the binder fibers intersect with other fibers. The bonding gives the material tensile strength and toughness qualities that make the absorbent substrate well suited for use in converting processes. The presence of the polymer fibers and the bonding of the binder fibers, however, can increase the hydrophobic properties of the overall substrate. When the binder fibers are present or concentrated within the top surface layer of the absorbent substrate, the fluid intake properties of the substrate can be slow and unsatisfactory. Incorporating less binder fibers into the product or controlling the process to minimize bonding of the fibers, however, can slow production rates and produce a product with reduced strength and integrity.

[0251] During the wetlaid process, surfactants can be used to produce the absorbent substrate. In addition, binder fibers and synthetic fibers can be provided with a spin finish for improving the wettability of the fibers. During the wetlaid process of forming the absorbent substrate, however, these wetting agents are typically washed off and become ineffective for increasing fluid intake rates.

[0252] The present inventors discovered that applying a surfactant composition to the absorbent substrate at a particular point during the manufacturing process can dramatically and unexpectedly improve fluid intake rates, especially at low surfactant loadings. For example, simply applying copious amounts of surfactants to the absorbent substrate after formation can actually cause liquid pooling on the surface of the substrate and not improve fluid intake rates. Through the process of the present disclosure, however, one or more surfactants are applied to the substrate at relatively low levels and in a manner that enables the surfactants to penetrate the top layer of the substrate. In this manner, fluids that contact the top surface of the substrate are rapidly absorbed into the interior of the substrate.

[0253] For example, in one aspect, the surfactant composition containing at least one surfactant is applied to the absorbent substrate prior to drying the substrate. For instance, the surfactant composition can be applied to the absorbent substrate after the substrate has been formed and drained but while the substrate contains moisture in an amount greater than about 8% by weight, such as in an amount greater than about 10% by weight, such as in an amount greater than about 15% by weight, such as in an amount greater than about 20% by weight, such as in an amount greater than about 25% by weight, such as in an amount greater than about 30% by weight, such as in an amount greater than about 35% by weight, such as in an amount greater than about 40% by weight, and in an amount less than about 60% by weight, such as in an amount less than about 50% by weight, such as in an amount less than about 40% by weight, such as in an amount less than about 30% by weight. In this manner, one or more surfactants can be absorbed into the substrate prior to drying and before the binder fibers are activated.65119655PCT04 KCX-2169-PCT

[0254] In another aspect, the surfactant composition containing one or more surfactants is applied to the absorbent substrate prior to the binder fibers contained in the substrate being activated and being substantially bonded together. For instance, the surfactant composition can be applied to the absorbent substrate prior to the absorbent substrate being heated to a temperature above the bonding temperature of the binder fibers (independent of moisture content).

[0255] As described above, applying the surfactant composition to the absorbent substrate before the absorbent substrate has been dried and / or before the binder fibers have been activated has been found to enable penetration of the surfactant composition into the absorbent substrate while minimizing the amount of surfactant used. The Surfactant Penetration Quantification Test is a method to quantitatively measure the concentration and distribution of a surfactant in the Z-dimension (depth dimension) of a single or multi-layered porous substrate. The method uses SEM microscopy imaging the thickness of the substrate and subsequent image analysis protocol for determining surfactant concentration. The test is designed to determine the concentration and distribution of an element that is associated with the surfactant, such as sulfur. For instance, in one aspect, the Surfactant Penetration Quantification Test method determines the concentration and distribution of sulfur in the depth dimension of the absorbent substrate when the surfactant applied to the substrate contains sulfur.

[0256] Absorbent substrates made in accordance with the present disclosure, when subjected to the Surfactant Penetration Quantification Test, can display surfactant penetration through at least 5% of the thickness of the substrate, such as through at least about 10% of the thickness of the substrate, such as through at least about 15% of the thickness of the substrate, such as through at least about 20% of the thickness of the substrate, such as through at least about 25% of the thickness of the substrate. Surfactant penetration is generally less than 100% of the thickness of the substrate, such as less than about 50% of the thickness of the substrate. Ideally, the surfactant penetrates the absorbent substrate throughout the top surface but does not combine and mix with the superabsorbent material contained within the center of the substrate. In this manner, the surfactant can greatly increase fluid intake rates without interfering with the retention of fluids by the superabsorbent material.

[0257] In one aspect, the absorbent substrate made according to the present disclosure is multi-layer and includes an intake layer, a retention layer, and optionally a distribution layer. The retention layer, which contains a superabsorbent material is positioned between the intake layer and the distribution layer. The one or more surfactants applied to the intake layer can penetrate the thickness of the intake layer by greater than about 50%, such as by greater than about 60%, such as by greater than about65119655PCT04 KCX-2169-PCT

[0258] 70%, such as by greater than about 80%, such as by greater than about 90% when subjected to the Surfactant Penetration Quantification Test.

[0259] In one aspect, the surfactant can be present over the entire thickness of the substrate, but can be more concentrated in the top half of the substrate, which can dramatically increase fluid intake rates. For instance, the surfactant composition can be applied such that, when tested according to the Surfactant Penetration Quantification Test, at least about 42 %, such as at least about 44%, such as at least about 46% by weight of the surfactant remains in the top 50% of the thickness of the substrate. In addition, the surfactant composition can be applied such that, when tested according to the Surfactant Penetration Quantification Test, at least about 8% by weight, such as at least about 10% by weight, such as at least about 12% by weight, such as at least about 14% by weight, such as at least about 16% by weight, such as at least about 18% by weight, such as at least about 20% by weight of the surfactant remains in the top 25% of the thickness of the substrate.

[0260] The surfactant composition of the present disclosure can include all different types of surfactants. The one or more surfactants contained in the surfactant composition, for instance, can comprise a nonionic surfactant, an anionic surfactant, a cationic surfactant, or a zwitterionic surfactant.

[0261] In one aspect, for instance, the surfactant composition contains an anionic surfactant.

[0262] Anionic surfactants carry a negative charge and lower the surface tension of liquids allowing them to spread more easily across the surface of the absorbent substrate. Examples of anionic surfactants include alkyl sulfates, alkyl ether sulfates, sulfonates, and mixtures thereof. Particular anionic surfactants that may be used include sulfosuccinate surfactants, such as dialkyl sulfosuccinate surfactants, glucoside surfactants, such as laurylglucoside hydroxypropyl sulfonate, phosphate surfactants such as cetyl phosphate, sodium lauryl sulfate, sodium lauryl ether sulfate, and the like.

[0263] Alternatively, the surfactant contained in the surfactant composition can comprise a nonionic surfactant. In one aspect, the surfactant composition can contain a nonionic surfactant blended with an ionic surfactant. Nonionic surfactants do not carry a charge but also lower the surface tension of liquids enabling the liquids to spread more easily across the surface of the absorbent substrate. Nonionic surfactants that may be incorporated into the surfactant composition include alcohol ethoxylates, alkylphenol ethoxylates, sorbitan esters, polysorbates, and the like.

[0264] Particular examples of nonionic surfactants that can be used include a blend of hydrogenated ethoxylated castor oil and sorbitan monooleate, laureth ethoxylate, polysorbate 20, a cocamide surfactant such as cocamide diisopropanolamine, a polyethylene glycol glyceryl cocoate, a glucoside such as decyl glucoside or caprylyl / capry I glucoside, a glyceride such as polyethylene glycol65119655PCT04 KCX-2169-PCT

[0265] caprylic / capric glyceride, or mixtures thereof. In one aspect, a silicone surfactant can be used such as a dimethicone. In one embodiment, however, the surfactant composition is silicone-free.

[0266] Cationic surfactants that can be used include various quaternary compounds. Cationic surfactants include, for instance, cetyltrimethyl ammonium bromide, PEG-15 cocomonium chloride, polyquat 10, an alkyl polyethoxyphosphate ether, or the like.

[0267] Zwitterionic surfactants that can be used include a betaine such as an alkyl-betaine or cocamidopropyl betaine, or a glucoside copolymer such as sodium bis-hydroxyethyl glycinate lauryl glucoside copolymer and the like.

[0268] The surfactant composition can be applied to the absorbent substrate using any suitable method or technique. In one aspect, the surfactant composition is applied so as to evenly cover the surface of the absorbent substrate. For instance, in one aspect, the surfactant composition can be sprayed onto the absorbent substrate using one or more spray booms. Alternatively, the surfactant composition can be applied using a size press. Other ways in which the surfactant composition can be applied to the absorbent substrate include blade coating, foam application, curtain coating, gravure coating, slot die coating, electrostatic spraying, air knife coating, misting, printing such as flexographic printing, padding, or the like.

[0269] As described above, by applying the surfactant prior to drying the absorbent substrate and / or prior to activating the binder fibers, the amount of surfactant applied to the substrate can be minimized. For instance, the surfactant composition can be applied to the absorbent substrate such that the total amount of surfactant applied to the substrate is less than about 2 gsm, such as less than about 1.5 gsm, such as less than about 1 gsm, such as less than about 0.8 gsm, such as less than about 0.6 gsm, such as less than about 0.5 gsm, such as less than about 0.4 gsm, such as less than about 0.35 gsm, such as less than about 0.3 gsm, such as less than about 0.25 gsm, such as less than about 0.2 gsm. One or more surfactants can be applied to the absorbent substrate in an amount greater than about 0.001 gsm, such as in an amount greater than about 0.01 gsm, such as in an amount greater than about 0.05 gsm, such as in an amount greater than about 0.08 gsm, such as in an amount greater than about 0.1 gsm, such as in an amount greater than about 0.15 gsm, such as in an amount greater than about 0.2 gsm.

[0270] Once absorbent substrates made according to the present disclosure are dried and the binder fibers are activated by forming bond sites within the absorbent structure where the fibers overlap, the absorbent substrate can display excellent fluid intake rates even when containing significant amounts of polymer fibers in the top layer of the substrate. For instance, when tested according to the Cut Cradle Test, absorbent substrates made according to the present disclosure can display a first free65119655PCT04 KCX-2169-PCT

[0271] fluid of less than about 15 g, such as less than about 13 g, such as less than about 12 g, such as less than about 10 g, such as less than about 9 g, such as less than about 8 g after a 38 ml insult. The absorbent substrate can display a second free fluid of less than about 4 g, such as less than about 3.5 g, such as less than about 3 g, such as less than about 2.5 g, such as less than about 2 g, such as less than about 1.5 g, such as less than about 1 g, such as less than about 0.8 g, such as less than about 0.5 g, such as less than about 0.4 g after two 38 ml insults.

[0272] The absorbent substrate can also display a Cut Cradle 1st free fluid of less than about 32 g, such as less than about 30 g after a 105 ml insult and a 2nd free fluid of less than 50 g, such as less than about 48 g after two 105 ml insults.

[0273] The absorbent substrate can display a Closed Cradle 1st intake time of less than about 45 sec, such as less than about 40 sec, such as less than about 38 sec, can display a Closed Cradle 2nd intake time of less than about 150 sec, such as less than about 140 sec, such as less than about 130 sec, can display a Closed Cradle 3rd intake time of less than about 180 sec, such as less than about 170 sec, such as less than about 175 sec, and / or can display a rewet of less than about 0.6 g, such as less than about 0.5 g.

[0274] In addition to excellent fluid intake characteristics, absorbent substrates made according to the present disclosure also have excellent toughness and strength. For instance, absorbent substrates made according to the present disclosure can display a tensile strength in at least one direction of greater than about 1 ,800 gf, such as greater than about 1,900 gf, such as greater than about 2,000 gf, and less than about 4,000 gf.

[0275] In one aspect, the absorbent articles contain a multi-layer absorbent substrate that has excellent physical properties while maximizing the use of a superabsorbent material. In one embodiment, the multi-layer absorbent substrate contained within the absorbent article comprises a foam formed nonwoven material that can be produced in rolls and then cut to a desired size. The multi-layer absorbent substrate can be made relatively thin and flexible while still having sufficient strength to be manipulated during formation of the articles.

[0276] For instance, the multi-layered absorbent substrate can include an intake or top layer, a retention or absorbent layer, and optionally a fluid distribution layer. The retention layer is positioned between the intake layer and the distribution layer. The intake layer contains coarse fibers, such as synthetic polymer fibers and / or binder fibers (e.g. bi-component fibers), in order to provide adequate web integrity. The intake layer, however, is primarily comprised of polymer synthetic fibers and thus has hydrophobic characteristics, especially after the binder fibers have been activated and form bond sites within the structure. In accordance with the present disclosure, however, a surfactant is applied65119655PCT04 KCX-2169-PCT

[0277] to the absorbent substrate prior to drying the absorbent substrate and / or prior to a substantial amount of interfiber bonding. Through the process of the present disclosure, fluid intake rates of the intake layer and the absorbent substrate are dramatically and unexpectedly improved. Consequently, absorbent substrates made according to the present disclosure can have excellent fluid intake rates even when the top layer of the substrate is devoid of liquid absorbent materials, such as superabsorbent materials and / or cellulose fibers.

[0278] The retention layer contains superabsorbent particles combined with resilient fibers. The superabsorbent particles are spaced apart within the retention layer for absorbing different types of fluids.

[0279] The fluid distribution layer, on the other hand, can contain binder fibers in addition to cellulose fibers and / or polymer synthetic fibers. In one aspect, the fluid distribution layer can contain pulp fibers or cellulose fibers in amounts sufficient to provide a capillary pressure gradient to drive fluid down into the layer. The fluid distribution layer, for instance, can prevent against early fluid saturation of the retention layer thus allowing additional insults to be absorbed at fast rates. The fluid distribution layer also captures the superabsorbent material within the middle of the product and provides fluid distribution and web integrity.

[0280] Referring to FIG. 1, for exemplary purposes only, one embodiment of an absorbent article 200 made in accordance with the present disclosure is shown. Absorbent articles made in accordance with the present disclosure can comprise diapers, child training pants, other absorbent child pants, adult incontinence products, and the like. In one particular embodiment as shown in FIG. 1, the present disclosure is directed to an absorbent article that serves as a feminine hygiene product, such as a feminine care absorbent article 200.

[0281] More particularly, the article 200 includes a liner 226, a baffle 228, and an absorbent substrate 233 positioned between the liner 226 and the baffle 228. The liner 226 defines a body-facing surface of the absorbent article 200. The absorbent substrate 233 is positioned inwardly from the outer periphery of the absorbent article 200 and includes a body-facing side positioned adjacent the liner 226 and a garment-facing surface positioned adjacent the baffle 228. Typically, the liner 226 and the baffle 228 are joined by adhesive bonding, ultrasonic bonding, or any other suitable joining method known in the art, the sealed edges defining an overall sealed peripheral edge 299 of the article 200. The article 200 may take on various geometries but will generally have opposite lateral sides and longitudinal ends.

[0282] The liner 226 helps provide comfort and conformability, and also helps direct bodily exudates away from the body toward the absorbent substrate 233. Typically, the liner 226 and the baffle 22865119655PCT04 KCX-2169-PCT

[0283] have peripheral margins 299 that extend outwardly beyond the terminal, peripheral edges of the absorbent member 230, and the extending margins are joined together to partially or entirely, surround or enclose the absorbent core. The liner 226 contacts the body of the user and is liquid-permeable. The liner 226 may be formed from one or multiple layers of materials. The liquid-permeable liner 226 has an outwardly facing surface that may contact the body of the wearer and receive fluids from the body. The liner 226 may define an inner region positioned between laterally spaced first and second outer regions. The inner and outer regions may be formed from a single section of material, or from multiple sections. Whether having one or multiple sections, the liner 226 may be made from any liquid-permeable material known in the art. For example, the liner 226 can be constructed of any woven or nonwoven material that is easily penetrated by bodily exudates. Examples of suitable materials include rayon, bonded carded webs of polyester, polypropylene, polyethylene, nylon, or other heat-bondable fibers, polyolefins, such as copolymers of polypropylene and polyethylene, linear low-density polyethylene, and aliphatic esters such as polylactic acid. Finely perforated film webs and net material can also be used. A specific example of a suitable topsheet material is a bonded carded web made of polypropylene and polyethylene, such as that used as topsheet stock for KOTEX® pantiliners. Such materials typically have a basis weight of less than about 100 gsm, and in some embodiments, from about 10 gsm to about 40 gsm.

[0284] The baffle 228 is generally liquid-impermeable and designed to face the inner surface, i.e. , the crotch portion of an undergarment (not shown). The baffle 228 may permit a passage of air or vapor out of the absorbent article 200, while still blocking the passage of liquids. Any liquid-impermeable material may generally be utilized to form the baffle 228. For example, one suitable material that may be utilized is a microporous polymeric film, such as polyethylene or polypropylene. In particular embodiments, a polyethylene film is utilized that has a thickness in the range of about 0.2 mils to about 5.0 mils, and particularly between about 0.5 to about 3.0 mils. A specific example of a baffle material is a polyethylene film such as that used in KOTEX® pantiliners.

[0285] A nonwoven material 233 or an absorbent substrate made in accordance with the present disclosure is incorporated into the feminine care absorbent article 200. In particular, the absorbent substrate 233 is positioned between the liner 226 and the baffle 228 for absorbing and retaining body exudates, including menses and urine. As described above, in one embodiment, the nonwoven material 233 can comprise a multi-layer (or multi-zone) absorbent substrate.

[0286] The liner 226 may be maintained in secured relation with the absorbent structure 230 by bonding all or a portion of the adjacent surfaces to one another. A variety of bonding mechanisms known to one of skill in the art may be utilized to achieve any such secured relation. Examples of such65119655PCT04 KCX-2169-PCT

[0287] mechanisms include, but are not limited to, the application of adhesives in a variety of patterns between the two adjoining surfaces, entangling at least portions of the adjacent surface of the absorbent with portions of the adjacent surface of the cover, or fusing at least portions of the adjacent surface of the cover to portions of the adjacent surface of the absorbent (e.g., ultrasonically fusing).

[0288] If desired, the feminine care absorbent article 200 may also include laterally extending wing portions 242 that may be integrally connected to side regions along the intermediate portion of the article. For example, the wing portions 242 may be separately provided members that are subsequently attached or otherwise operatively joined to the intermediate portion of the article. In other configurations, the wing portions may be unitarily formed with one or more components of the article. As representatively shown in FIG. 1, for example, either or both wing portions 242 may be formed from a corresponding, operative extension of the material employed to form the baffle 228. Alternatively, either or both wing portions 242 may be formed from a corresponding, operative extension of the material employed to form the liner 226, or formed from a corresponding, operative combination of the topsheet and baffle materials.

[0289] If desired, the absorbent article 200 can further include an embossing pattern. The embossing pattern can be embossed into the liner and can extend at least partially into the middle of the absorbent substrate.

[0290] In one aspect, the absorbent substrate 233 comprises a multi-layer substrate that can be formed through a foam forming process. The absorbent substrate 233, for instance, can be a nonwoven material that is foam formed, wound into a roll, combined with the liner 226 and optionally the baffle 228 and then cut to a desired shape.

[0291] The absorbent substrate can contain at least two layers, and, in one embodiment, contains three layers. The absorbent substrate or nonwoven material, for instance, can include an intake layer that is designed to be placed adjacent to the wearer, a retention layer for absorbing and retaining bodily fluids, and, optionally, a distribution layer. The distribution layer can form a bottom exterior layer and may be designed to prevent superabsorbent material from escaping the nonwoven material from the retention layer.

[0292] Referring to FIG. 2, for exemplary purposes, one example of a nonwoven material 10 made in accordance with the present disclosure is shown. FIG. 2 illustrates a three-layer embodiment. In particular, the nonwoven material 10 includes an intake layer 12 positioned adjacent to a retention layer 13. An interface 15 is located between the intake layer 12 and the retention layer 13. The nonwoven material 10 further includes a distribution layer 17. As shown, the retention layer 13 is positioned between the intake layer 12 and the distribution layer 17. An interface 19 is located65119655PCT04 KCX-2169-PCT

[0293] between the retention layer 13 and the distribution layer 17. In one aspect, some of the materials or fibers contained in the intake layer 12 can mix with some of the materials or fibers contained in the retention layer 13 along the interface 15. Similarly, some of the fibers or materials contained in the retention layer 13 can mix with some of the fibers or materials contained in the distribution layer 17 at the interface 19. The interfaces 15 and 19 can provide the benefit of having some fiber distribution between adjacent zones or layers for providing enhanced stabilization properties.

[0294] The intake layer 12 and the distribution layer 17 can serve as containment layers for the retention layer 13. In particular, the intake layer 12 and the distribution layer 17 can be configured to be relatively thin and have a low basis weight while providing enough strength for handling and converting and while adding minimal stiffness. The retention layer 13 can contain a superabsorbent material that is prevented from contacting a user or wearer due to the presence of the intake layer 12 and the distribution layer 17. In this manner, the intake layer 12 and the distribution layer 17 can improve the feel and comfort of the nonwoven material 10 by reducing any gritty feel that may occur when there is contact with superabsorbent materials. The intake layer 12 and the distribution layer 17 can also prevent superabsorbent materials from escaping making the nonwoven material easier to handle and process.

[0295] The intake layer 12 can be a top layer that is configured to face a wearer when the nonwoven material 10 is incorporated into an absorbent article. In one aspect, the intake layer 12 can be designed to provide strength and toughness. In accordance with the present disclosure, the intake layer 12 can be modified so as to quickly allow fluids including menses and urine to be absorbed by the retention layer 13. For example, in one embodiment, the intake layer 12 can be treated with a surfactant at a particular point in the manufacturing process.

[0296] In one aspect, the intake layer 12 can contain a mixture of binder fibers, synthetic polymer fibers, and optionally crosslinked pulp fibers. Binder fibers that can be incorporated into the intake layer 12 include mono-component fibers and multi-component fibers. The multi-component fibers, for instance, can include a core polymer surrounded by a sheath polymer. The sheath polymer can be comprised of a low melting thermoplastic polymer such as polyethylene. In one aspect, the binder fibers comprise bicomponent fibers containing a core polymer made from a polyester polymer or a polypropylene polymer. For example, the core polymer can be a polyethylene terephthalate polymer. The sheath polymer, on the other hand, can have a lower melting temperature than the core polymer and can comprise a polyolefin, such as polyethylene.

[0297] The binder fibers can have any suitable size and length. For instance, the binder fibers can have a length of between about 0.5 mm to about 50 mm, such as from about 0.75 mm to about 3065119655PCT04 KCX-2169-PCT

[0298] mm. In one aspect, the binder fibers have a length of from about 1 mm to about 25 mm. The binder fibers, for instance, can have an average length of greater than about 2 mm, such as greater than about 3 mm, such as greater than about 4 mm, such as greater than about 5 mm, and less than about 12 mm, such as less than about 8 mm. The binder fibers can have a size of from about 0.5 dtex to about 20 dtex. In one aspect, for instance, the fibers can have a size of from about 0.8 dtex to about 3.5 dtex. In an alternative aspect, the binder fibers can have a size of from about 3.5 dtex to about 8 dtex.

[0299] In one embodiment, the intake layer 12 can contain a mixture of different binder fibers, such as first binder fibers and second binder fibers. The first binder fibers can comprise bi-component fibers having a size of from about 3.5 dtex to about 15 dtex and the second binder fibers can comprise bi-component fibers having a size of from about 0.8 dtex to about 3.5 dtex. All of the binder fibers can have an average length of from about 2 mm to about 8 mm, such as from about 4 mm to about 7 mm.

[0300] In one aspect, the intake layer 12 can contain binder fibers in an amount from about 30% by weight to about 75% by weight, including all increments of 1% therebetween. For example, the intake layer 12 can contain binder fibers in an amount greater than about 35% by weight, such as in an amount greater than about 40% by weight, such as in an amount greater than about 45% by weight, such as in an amount greater than about 50% by weight, such as in an amount greater than about 55% by weight. The binder fibers can generally be present in an amount less than about 75% by weight, such as less than about 70% by weight, such as in an amount less than about 65% by weight, such as in an amount less than about 60% by weight.

[0301] In addition to containing binder fibers, the intake layer 12 can contain various other materials, including other fibers. In one aspect, for instance, the intake layer 12 can contain synthetic polymer fibers. The synthetic polymer fibers, for instance, can be made from a polymer material and can be non-absorbent. As described above, in one aspect, the nonwoven material 10 can be produced using a foam forming process in which the fibers and other materials are suspended in a foam and then deposited onto a forming surface to form the multi-layer structure. Of advantage, the foam forming process can accommodate all different types of materials and fibers including polymer synthetic fibers. For example, the polymer synthetic fibers can have a bending stiffness that is substantially unimpacted by the presence of the forming fluid.

[0302] Examples of synthetic polymer fibers include polyolefin, polyester (PET), polyamide, polylactic acid, or other fiber forming polymers. Polyolefin fibers, such as polyethylene (PE) and polypropylene (PP), and polyethylene terephthalate fibers are particularly well suited for use in the present disclosure. In some embodiments, non-absorbent fibers can be recycled fibers, compostable fibers, and / or marine65119655PCT04 KCX-2169-PCT

[0303] degradable fibers. In this regard, due to its very low levels of absorbency to water, water resistant fibers do not experience a significant change in bending stiffness upon contacting an aqueous fluid and therefore are capable of maintaining an open composite structure upon wetting. The fiber diameter of a fiber can contribute to enhanced bending stiffness. For example, a PET fiber has a higher bending stiffness than a polyolefin fiber whether in dry or wet states. The higher the fiber denier, the higher the bending stiffness a fiber exhibits. Water resistant fibers desirably have a water retention value (WRV) less than about 1 and still more desirably between about 0 and about 0.5. In certain aspects, it is desirable that the fibers, or at least a portion thereof, include non-absorbent fibers.

[0304] The synthetic and / or water resistant fibers can have fiber length greater than about 0.2 mm including, for example, having an average fiber size between about 0.5 mm and about 50 mm or between about 0.75 and about 30 mm or even between about 1 mm and about 25 mm. The average fiber size of the synthetic fibers, for instance, can be greater than about 2 mm, such as greater than about 4 mm, and less than about 18 mm, such as less than about 12 mm, such as less than about 10 mm, such as less than about 8 mm.

[0305] In some embodiments, the synthetic and / or water resistant fibers can have a crimped structure to enhance bulk generation capability of the foam formed fibrous substrate. For example, a PET crimped staple fiber may be able to generate a higher caliper (or result in a low sheet density) in comparison to a PET straight staple fiber with the same fiber diameter and fiber length.

[0306] The size of the synthetic polymer fibers can be from about 0.5 dtex to about 25 dtex. For instance, the size of the synthetic polymer fibers can be greater than about 5 dtex, such as greater than about 8 dtex, such as greater than about 10 dtex, and less than about 20 dtex, such as less than about 15 dtex.

[0307] For exemplary purposes, the intake layer 12 can contain synthetic polymer fibers generally in an amount from about 10% by weight to about 60% by weight, including all increments of 1% by weight therebetween. For instance, the polymer synthetic fibers can be present in the intake layer 12 in an amount greater than about 25% by weight, such as in an amount greater than about 30% by weight, such as in an amount greater than about 35% by weight. The polymer synthetic fibers can be present in the intake layer 12 in an amount less than about 60% by weight, such as in an amount less than about 55% by weight, such as in an amount less than about 50% by weight. In one embodiment, the intake layer 12 only contains binder fibers combined and blended with synthetic polymer fibers.

[0308] In addition to or instead of polymer synthetic fibers, the intake layer 12 can also optionally contain cellulose fibers. Various different types of cellulose fibers can be incorporated into the intake layer 12. In one aspect, for instance, the intake layer 12 contains crosslinked pulp fibers in amounts65119655PCT04 KCX-2169-PCT

[0309] less than 20% by weight, such as less than about 10% by weight. In one embodiment, the intake layer does not contain cellulose fibers and / or only contains binder fibers combined with synthetic fibers.

[0310] In one aspect, the intake layer 12 can have a basis weight that is less than about 65 gsm, such as less than about 60 gsm, such as less than about 55 gsm, such as less than about 50 gsm, and greater than about 30 gsm, such as greater than about 35 gsm, such as greater than about 40 gsm, such as greater than about 45 gsm, such as greater than about 50 gsm.

[0311] The retention layer 13 contained in the nonwoven material 10 is generally configured to absorb fluids, particularly liquids, and includes absorbent material. The absorbent material can include absorbent particles including fibers and / or other absorbent components. The retention layer 13 can contain a superabsorbent material in combination with a plurality of fibers. For example, in one embodiment, the retention layer 13 includes superabsorbent material combined with resilient fibers and optionally binder fibers.

[0312] Various different superabsorbent materials (SAM) can be incorporated into the retention layer 13. SAM is commonly provided in a particulate form and, in certain aspects, can comprise polymers of unsaturated carboxylic acids or derivatives thereof. In some forms, however, SAM can be configured in fiber form. These polymers are often rendered water insoluble, but water swellable, by crosslinking the polymer with a di- or polyfunctional internal crosslinking agent. These internally cross-linked polymers are at least partially neutralized and commonly contain pendant anionic carboxyl groups on the polymer backbone that enable the polymer to absorb aqueous fluids, such as body fluids.

[0313] Typically, the SAM particles are subjected to a post-treatment to crosslink the pendant anionic carboxyl groups on the surface of the particle. SAMs are manufactured by known polymerization techniques, desirably by polymerization in aqueous solution by gel polymerization. The products of this polymerization process are aqueous polymer gels, i.e., SAM hydrogels that are reduced in size to small particles by mechanical forces, then dried using drying procedures and apparatus known in the art. The drying process is followed by pulverization of the resulting SAM particles to the desired particle size. Examples of superabsorbent materials include, but are not limited to, those described in US7396584 Azad et al, US7935860 Dodge et al, US2005 / 5245393 to Azad et al, US2014 / 09606 to Bergam et al, W02008 / 027488 to Chang et al. and so forth.

[0314] In some embodiments involving SAM, the SAM may be treated by a water-soluble protective coating having a rate of dissolution selected such that the component is not substantially exposed to the aqueous liquid carrier until the highly-expanded foam has been formed and drying operations initiated that can remove the coating. Alternatively, in order to prevent or limit premature expansion during processing, the SAM may be introduced into the process at low temperatures.65119655PCT04 KCX-2169-PCT

[0315] The retention layer 13 can also contain resilient fibers. The resilient fibers are blended with the superabsorbent material and provide Z-directional loft to the layer which permits the spacing of the superabsorbent material within the layer.

[0316] The resilient fibers, for instance, can comprise particular types of cellulose fibers or can comprise synthetic fibers. Resilient cellulose fibers include crosslinked pulp fibers, bleached chemithermomechanical pulp fibers, regenerated cellulose fibers, and mixtures thereof. Synthetic resilient fibers can include synthetic polymer fibers such as polyester fibers, polylactic acid fibers, polyhydroxyalkanoate fibers, polypropylene fibers, and mixtures thereof. In one aspect, the retention layer 13 can contain resilient fibers comprising a mixture of resilient cellulose fibers and resilient synthetic fibers.

[0317] In addition to the superabsorbent material and the resilient fibers, the retention layer 13 can optionally contain binder fibers. The binder fibers can be the same fibers as described above with respect to the intake layer 12. For instance, the retention layer 13 can contain a single type of binder fiber or can contain a mixture of binder fibers having different sizes.

[0318] The fiber basis weight (excluding the superabsorbent material) of the retention layer 13 can generally be from about 50 gsm to about 200 gsm. For instance, the fiber basis weight can be greater than about 60 gsm, such as greater than about 70 gsm, such as greater than about 85 gsm, such as greater than about 90 gsm, such as greater than about 95 gsm, such as greater than about 100 gsm, and less than about 150 gsm, such as less than about 130 gsm, such as less than about 125 gsm, such as less than about 120 gsm.

[0319] In one embodiment, all of the fibers contained in the retention layer 13 can comprise resilient fibers. Alternatively, the retention layer 13 can contain binder fibers in an amount less than about 30% by weight, such as in an amount less than about 20% by weight, such as in an amount less than about 15% by weight, such as in an amount greater than about 5% by weight, such as in an amount greater than about 10% by weight based upon the total weight of fibers present in the layer. The resilient fibers can be present in the retention layer 13 in an amount generally from about 50% by weight to about 100% by weight, such as in an amount greater than about 60% by weight, such as in an amount greater than about 70% by weight, such as in an amount greater than about 80% by weight.

[0320] The basis weight of the superabsorbent material contained in the retention layer 13 can be from about 50 gsm to about 700 gsm. In one aspect, the basis weight of the superabsorbent material contained in the retention layer 13 is greater than about 100 gsm, such as greater than about 150 gsm, such as greater than about 180 gsm, such as greater than about 190 gsm, such as greater than65119655PCT04 KCX-2169-PCT

[0321] about 200 gsm, and less than about 600 gsm, such as less than about 500 gsm, such as less than about 400 gsm.

[0322] As shown in FIG. 2, the nonwoven material 10 further includes a distribution layer 17. The distribution layer 17 can be made from different fiber furnishes. For instance, the distribution layer can contain binder fibers alone, binder fibers in combination with cellulose fibers, binder fibers in combination with synthetic fibers, or binder fibers in combination with cellulose fibers and polymer synthetic fibers.

[0323] In one aspect, the distribution layer 17 contains binder fibers, such as any of the binder fibers described above with respect to the intake layer 12. For example, the distribution layer 17 can contain bi-component binder fibers having a size of from about 0.8 dtex to about 5 dtex, such as from about 0.8 dtex to about 1.6 dtex. The binder fibers can be present in the distribution layer 17 generally in an amount from about 10% by weight to about 55% by weight. For instance, the binder fibers can be present in the distribution layer 17 in an amount greater than about 15% by weight, such as in an amount greater than about 20% by weight, such as in an amount greater than about 25% by weight, such as in an amount greater than about 30% by weight, such as in an amount greater than about 35% by weight, and in an amount less than about 50% by weight, such as in an amount less than about 45% by weight.

[0324] In one aspect, the distribution layer 17 only contains binder fibers in combination with cellulose fibers.

[0325] The cellulose fibers can generally be present in the distribution layer 17 in an amount from about 20% by weight to about 90% by weight. For instance, the cellulose fibers can be present in an amount greater than about 30% by weight, such as in an amount greater than about 40% by weight, such as in an amount greater than about 50% by weight, and in an amount less than about 80% by weight, such as in an amount less than about 70% by weight. The cellulose fibers can comprise pulp fibers, such as softwood fibers, hardwood fibers, or the like. The cellulose fibers can also comprise cellulose resilient fibers, such as crosslinked cellulose fibers. In one embodiment, the cellulose fibers comprise a mixture of softwood fibers and crosslinked pulp fibers in a ratio of from about 1 :1 to about 4:1, such as in a ratio of from about 1.5:1 to about 2.5:1.

[0326] The distribution layer 17 as shown in FIG.2 can generally have a basis weight of less than about 70 gsm, such as less than about 65 gsm, such as less than about 60 gsm, such as less than about 55 gsm, such as less than about 50 gsm. The basis weight of the distribution layer 17 can be greater than about 15 gsm, such as greater than about 20 gsm, such as greater than about 25 gsm.65119655PCT04 KCX-2169-PCT

[0327] In addition to the materials described above to form the different layers in the nonwoven material or multi-layer substrate, the multi-layer substrate can also contain various other additives and components. For example, wet strength additives can be added during formation of the substrate in order to help improve the relative strength of the multi-layer substrate.

[0328] Such strength additives suitable for use with paper making fibers and the manufacture of paper tissue are known in the art. Temporary wet strength additives may be cationic, nonionic or anionic. Examples of such temporary wet strength additives include PAREZ™ 631 NC and PAREZ(R) 725 temporary wet strength resins that are cationic glyoxylated polyacrylamides available from Cytec Industries, located at West Paterson, N.J. These and similar resins are described in US3556932 to Coscia et al. and US3556933 to Williams et al. Additional examples of temporary wet strength additives include dialdehyde starches and other aldehyde containing polymers such as those described in US6224714 to Schroeder et al.; US6274667 to Shannon et al.; US6287418 to Schroeder et al.; and US6365667to Shannon et al., and so forth.

[0329] Permanent wet strength agents comprising cationic oligomeric or polymeric resins may also be used in the present disclosure. Polyamide-polyamine-epichlorohydrin type resins such as KYMENE 557H sold by Solenis are the most widely used permanent wet-strength agents and are suitable for use in the present disclosure Such materials have been described in the following US3700623 to Keim; US3772076 to Keim; US3855158 to Petrovich et al.; US3899388to Petrovich et al.; US4129528 to Petrovich et al.; US4147586 to Petrovich et al.; US4222921 to van Eenam and so forth. Other cationic resins include polyethylenimine resins and aminoplast resins obtained by reaction of formaldehyde with melamine or urea. Permanent and temporary wet strength resins may be used together in the manufacture of composite cellulosic products of the present disclosure. Further, dry strength resins may also optionally be applied to the composite cellulosic webs of the present disclosure. Such materials may include, but are not limited to, modified starches and other polysaccharides such as cationic, amphoteric, and anionic starches and guar and locust bean gums, modified polyacrylamides, carboxymethylcellulose, sugars, polyvinyl alcohol, chitosan, and the like.

[0330] When a wet strength additive is used, it is preferable to select an additive that is compatible with the foam agent used for the foam process. For example, when a strength additive is a cationic resin, due to incompatibility between a cationic and an anionic substance, a cationic surfactant is preferably used as a foam agent, or vice versa. A non-ionic surfactant is usually compatible with any cationic and anionic strength additives.

[0331] One or more wet strength additives can be incorporated into only one of the layers of the nonwoven material 10. For instance, a wet strength additive can be incorporated into the intake layer,65119655PCT04 KCX-2169-PCT

[0332] can be incorporated into the retention layer, and / or can be incorporated into the distribution layer. In one embodiment, at least one wet strength additive is incorporated into all three layers.

[0333] If used, such wet strength additives can comprise between about 0.01 and about 5% of the dry weight of cellulose fibers contained in the multi-layer substrate. In certain embodiments, the strength additives can comprise between about 0.05% and about 2% of the dry weight of cellulose fibers or even between about 0.1% and about 1% of the dry weight of cellulose fibers.

[0334] Still other additional components may be added to multi-layer substrate materials. For materials that are formed utilizing foam forming processes, other additional components should be reviewed as to ensure they do not significantly interfere with the formation of the foam, the hydrogen bonding as between the cellulosic fibers or other desired properties of the material. As examples, additional additives may include one or more pigments, opacifying agents, anti-microbial agents, pH modifiers, skin benefit agents, odor absorbing agents, fragrances, thermally expandable microspheres, surfactants or hydrophilic agents, foam particles (such as, pulverized foam particles), and so forth as desired to impart or improve one or more physical or aesthetic attributes. In certain embodiments, the multi-layer substrate may include skin benefit agents such as, for example, antioxidants, astringents, conditioners, emollients, deodorants, external analgesics, film formers, humectants, hydrotropes, pH modifiers, surface modifiers, skin protectants, and so forth.

[0335] As will be described in greater detail below, the absorbent substrate is treated a surfactant composition containing at least one surfactant. The surfactant can comprise a non-ionic surfactant, an anionic surfactant, and / or possibly a cationic surfactant.

[0336] Nonwoven materials, as described herein can be preferably formed through a foam forming process. FIG. 3 provides a schematic of an exemplary apparatus 11 that can be used as part of a foam forming process to manufacture a nonwoven material 10 that is a foam formed product. The apparatus 11 of FIG. 3 can include a first tank 14 configured for holding a first fluid supply 16. In some embodiments, the first fluid supply 16 can be a foam. The first fluid supply 16 can include a fluid provided by a supply of fluid 18. In some embodiments, the first fluid supply 16 can include a plurality fibers provided by a supply of fibers 20, and preferably includes at least some absorbent fibers.

[0337] However, in other embodiments, the first fluid supply 16 can be free from a plurality of fibers altogether. The first fluid supply 16 can also include a foaming surfactant provided by a supply of foaming surfactant 22. In some embodiments, the first tank 14 can include a mixer 24, as will be discussed in more detail below. The mixer 24 can mix (e.g., agitate) the first fluid supply 16 to mix the fluid, fibers (if present), and foaming surfactant with air, or some other gas, to create a foam. The mixer 24 can also mix the foam with fibers (if present) to create a foam suspension of fibers in which65119655PCT04 KCX-2169-PCT

[0338] the foam holds and separates the fibers to facilitate a distribution of the fibers within the foam (e.g., as an artifact of the mixing process in the first tank 14). Uniform fiber distribution can promote desirable absorbent material 10 including, for example, strength and the visual appearance of quality.

[0339] The apparatus 11 can also include a second tank 26 configured for holding a second fluid supply 28. In some embodiments, the second fluid supply 28 can be a foam. The second fluid supply 28 can include a fluid provided by a supply of fluid 30 and a foaming surfactant provided by a supply of foaming surfactant 32. In some preferred embodiments, such as depicted in FIG. 3, the second fluid supply 28 is free from fibers. In other embodiments, the second fluid supply 28 can include a plurality of fibers in addition to or as an alternative to the fibers being present in the first fluid supply 16. In some embodiments, the second tank 26 can include a mixer 34. The mixer 34 can mix the second fluid supply 28 to mix the fluid and foaming surfactant with air, or some other gas, to create a foam.

[0340] In some embodiments, the apparatus 11 can also include a third tank 31 configured for holding a third fluid supply 33. In some embodiments, the third fluid supply 33 can be a foam. The third fluid supply 33 can include a fluid provided by a supply of fluid 35 and a plurality of fibers provided by a supply of fibers 37, and preferably includes at least some synthetic fibers. The third fluid supply 33 can also include a foaming surfactant provided by a supply of foaming surfactant 39. In some embodiments, the third tank 31 can include a mixer 41. The mixer 41 can mix the third fluid supply 33 to mix the fluid and foaming surfactant with air, or some other gas, to create a foam.

[0341] In some embodiments, the apparatus 11 can also include a fourth tank 66 configured for holding a fourth fluid supply 68. In some embodiments, the fourth fluid supply 68 can be a foam. The fourth fluid supply 68 can include a fluid provided by a supply of fluid 69 and a plurality of fibers provided by a supply of fibers 70. The fourth fluid supply 68 can also include a foaming surfactant provided by a supply of foaming surfactant 71. In some embodiments, the fourth tank 66 can include a mixer 72. The mixer 72 can mix the fourth fluid supply 68 to mix the fluid and foaming surfactant with air, or some other gas, to create a foam.

[0342] In tanks 14, 26, 31, 66 the first fluid supply 16, the second fluid supply 28, the third fluid supply 33, and the fourth fluid supply 68, respectively, can be acted upon to form a foam. In some embodiments, the foaming fluid and other components are acted upon so as to form a porous foam having an air content greater than about 50% by volume and desirably an air content greater than about 60% by volume. In certain aspects, the highly-expanded foam is formed having an air content of between about 60% and about 95% and in further aspects between about 65% and about 85%. In certain embodiments, the foam may be acted upon to introduce air bubbles such that the ratio of expansion (volume of air to other components in the expanded stable foam) is greater than 1 :1 and in65119655PCT04 KCX-2169-PCT

[0343] certain embodiments the ratio of ainother components can be between about 1.1 :1 and about 20:1 or between about 1.2:1 and about 15:1 or between about 1.5:1 and about 10:1 or even between about 2:1 and about 5:1.

[0344] The foam can be generated by one or more means known in the art. Examples of suitable methods include, without limitation, aggressive mechanical agitation such as by mixers 24, 34, 41, 72 injection of compressed air, and so forth. Mixing the components through the use of a high-shear, high-speed mixer is particularly well suited for use in the formation of the desired highly-porous foams. Various high-shear mixers are known in the art and believed suitable for use with the present disclosure. High-shear mixers typically employ a tank holding the foam precursor and / or one or more pipes through which the foam precursor is directed. The high-shear mixers may use a series of screens and / or rotors to work the precursor and cause aggressive mixing of the components and air. In a particular embodiment, the first tank 14, the second tank 26, the third tank 31 , and / or the fourth tank 66 is provided having therein one or more rotors or impellers and associated stators. The rotors or impellors are rotated at high speeds in order to cause flow and shear. Air may, for example, be introduced into the tank at various positions or simply drawn in by the action of the mixers 24, 34, 41, 72. While the specific mixer design may influence the speeds necessary to achieve the desired mixing and shear, in certain embodiments suitable rotor speeds may be greater than about 500 rpm and, for example, be between about 1000 rpm and about 6000 rpm or between about 2000 rpm and about 4000 rpm. In other embodiments, suitable rotor speeds may be less than 500 rpm.

[0345] In addition, it is noted the foaming process can be accomplished in a single foam generation step or in sequential foam generation steps for the first tank 14, the second tank 26, the third tank 31 , and / or the fourth tank 66. For example, in one embodiment, all of the components of the first fluid supply 16 in the first tank 14 (e.g., the supply of the fluid 18, fibers 20, and foaming surfactant 22) may be mixed together to form a slurry from which a foam is formed. Alternatively, one or more of the individual components may be added to the foaming fluid, an initial mixture formed (e.g. a dispersion or foam), after which the remaining components may be added to the initially foamed slurry and then all of the components acted upon to form the final foam. In this regard, the fluid 18 and foaming surfactant 22 may be initially mixed and acted upon to form an initial foam prior to the addition of any solids. Fibers, if desired, may then be added to the water / surfactant foam and then further acted upon to form the final foam. As a further alternative, the fluid 18 and fibers 20, such as a high density cellulose pulp sheet, may be aggressively mixed at a higher consistency to form an initial dispersion after which the foaming surfactant 22, additional water and other components, such as synthetic fibers, are added to form a second mixture which is then mixed and acted upon to form the foam.65119655PCT04 KCX-2169-PCT

[0346] The foam density of the foam forming the first fluid supply 16 in the first tank 14, the foam forming the second fluid supply 28 in the second tank 26, the third fluid supply 33 in the third tank 31, and / or the fourth fluid supply 68 in the fourth tank 66 can vary depending upon the particular application and various factors, such as the fiber stock used. In some implementations, for example, the foam density of the foam can be greater than about 100 g / L, such as greater than about 250 g / L, such as greater than about 300 g / L. The foam density is generally less than about 800 g / L, such as less than about 500 g / L, such as less than about 400 g / L, such as less than about 350 g / L. In some implementations, for example, a lower density foam is used having a foam density of generally less than about 350 g / L, such as less than about 340 g / L, such as less than about 330 g / L.

[0347] The apparatus 11 can also include a first pump 36, a second pump 38, third pump 43, and fourth pump 73. The first pump 36 can be in fluid communication with the first fluid supply 16 and can be configured for pumping the first fluid supply 16 to transfer the first fluid supply 16. The second pump 38 can be in fluid communication with the second fluid supply 28 and can be configured for pumping the second fluid supply 28 to transfer the second fluid supply 28. The third pump 43 can be in fluid communication with the third fluid supply 33 and can be configured for pumping the third fluid supply 33 to transfer the third fluid supply 33. The fourth pump 73 can be in fluid communication with the fourth fluid supply 68 and can be configured for pumping the fourth fluid supply 68 to transfer the fourth fluid supply 68. In some embodiments, the first pump 36, the second pump 38, the third pump 43, and / or the fourth pump 73 can be a progressive cavity pump or a centrifugal pump, however, it is contemplated that other suitable types of pumps can be used.

[0348] As depicted in FIG. 3, the apparatus 11 can also include a component feed system 40. The component feed system 40 can be used to deliver a supply of component 44, if one is desired for the multi-layer substrate 10, by delivering the component 44 to one or more fluid supply 16, 28, 33, 68 or directly to the headbox 80. One exemplary component feed system 40 that can be used can include a component supply area 42 for receiving a supply of a component. The component feed system 40 can also include an outlet conduit 46. The component feed system 40 can also include a hopper 48. The hopper 48 can be coupled to the component supply area 42 and can be utilized for refiling the supply of the component 44 to the component supply area 42.

[0349] In some embodiments, the component feed system 40 can include a bulk solids pump. Some examples of bulk solids pumps that may be used herein can include systems that utilize screws / augers, belts, vibratory trays, rotating discs, or other known systems for handling and discharging the supply of the component 44. Other types of feeders can be used for the component feed system 40, such as, for example, an ingredient feeder, such as those manufactured by Christy65119655PCT04 KCX-2169-PCT

[0350] Machine & Conveyor, Fremont, Ohio. The component feed system 40 can also be configured as a conveyor system in some embodiments.

[0351] In some embodiments, the component feed system 40 can also include a pressure control system 50. In some embodiments, the pressure control system 50 can include a housing 52. The housing 52 can form a pressurized seal volume around the component feed system 40. In other embodiments, the pressure control system 50 can be formed as an integral part to the structure component feed system 40 itself, such that a separate housing 52 surrounding the component feed system 40 may not be required. The pressure control system 50 can also include a bleed orifice 54 in some embodiments.

[0352] The supply of the component 44 can be in the form of a particulate and / or a fiber and / or a powder. In one embodiment as described herein, the supply of the component 44 can be superabsorbent material (SAM) in particulate form. In some embodiments, SAM can be in the form of a fiber. Of course, other types of components, as previously discussed, are also contemplated as being utilized in the apparatus 11 and methods for forming an absorbent material 10 as described herein. The component feed system 40 as described herein can be particularly beneficial for a supply of component 44 that is most suitably maintained in a dry environment with minimal of exposure to fluid or foam utilized in the apparatus 11 and methods described herein.

[0353] The apparatus 11 can also include a first mixing junction 56 and a second mixing junction 58.

[0354] In preferred embodiments, the first mixing junction 56 can be an eductor (also commonly referred to as a jet pump). The first mixing junction 56 can be in fluid communication with the outlet conduit 46 of the component feed system 40 and in fluid communication with the second fluid supply 28. The first mixing junction 56 can include a first inlet 60 and a second inlet 62. The first inlet 60 can be in fluid communication with the supply of the component 44 via the outlet conduit 46. The second inlet 62 can be in fluid communication with the second fluid supply 28. The first mixing junction 56 can also include a discharge 64. In preferred embodiments, the first mixing junction 56 can be configured as a co-axial eductor with the axis of the first inlet 60 being co-axial with the axis of the outlet conduit 46 that provides the supply of the component 44. The first mixing junction 56 can also be configured such that the discharge axis of the discharge 64 is co-axial with the outlet axis of the outlet conduit 46. As such, the first mixing junction 56 can be configured such that the axis of the first inlet 60 can be co-axial with the axis of the discharge 64 of the first mixing junction 56. The second inlet 62 providing the second fluid supply 28 to the first mixing junction 56 can be set up to enter the first mixing junction 56 on a side of the first mixing junction 56.65119655PCT04 KCX-2169-PCT

[0355] When configured as an eductor, the first mixing junction 56 can mix the supply of the component 44 from the component feed system 40 with the second fluid supply 28. By transferring the second fluid supply 28 into the first mixing junction 56 at the second inlet 62 and through the first mixing junction 56, the second fluid supply 28 provides a motive pressure to the supply of the component 44. The motive pressure can create a vacuum on the supply of the component 44 and the component feed system 40 to help draw the supply of the component 44 to mix and be entrained in the second fluid supply 28. In some embodiments, the motive pressure can create a vacuum on the supply of the component 44 of less than 1 ,5in Hg, however, in other embodiments, the motive pressure could create a vacuum on the supply of the component 44 of 5in. Hg or more, or Win Hg or more.

[0356] The pressure control system 50 can help manage proper distribution and entrainment of the supply of the component 44 to the second fluid supply 28. For example, when the second fluid supply 28 creates a motive pressure on the component feed system 40, the vacuum pulling on the supply of the component 44 may cause additional air to be entrained in the second fluid supply 28. In some circumstances, entraining additional air in the second fluid supply 28 may be desired, however, in other circumstances, it may be desirable to control the gas content of the second fluid supply 28 while inputting the supply of the component 44 to the second fluid supply 28 at the first mixing junction 56 For example, in some circumstances where the second fluid supply 28 is a foam, the amount of gas content in the foam may be desired to be kept relatively fixed as the foam passes through the first mixing junction 56. Thus, the pressure control system 50 can control the pressure on the component feed system 40 to help counteract the motive pressure on the supply of the component 44 and the component feed system 40 created by the second fluid supply 28.

[0357] In some embodiments, the pressure control system 50 can include sealing off the component feed system 40. For example, as discussed above, the pressure control system 50 can include a housing 52 to provide a seal on the component feed system 40. Sealing the component feed system 40 can help to prevent additional air entrainment in the second fluid supply 28 when the supply of the component 44 is introduced into the second fluid supply 28 in the first mixing junction 56.

[0358] However, in some embodiments, it may be beneficial to also include additional capability to the pressure control system 50. For example, in some embodiments, the pressure control system 50 can include a bleed orifice 54. The bleed orifice 54 can be configured to bleed-in pressure, such as atmospheric air pressure, to provide additional pressure control of the component feed system 40. It has been discovered that by providing a bleed-in orifice 54 to provide some bleed-in of atmospheric air pressure to the component feed system 40, back-splashing of the second fluid supply 28 in the first65119655PCT04 KCX-2169-PCT

[0359] mixing junction 56 can be reduced or eliminated. Reducing back-splashing of the second fluid supply 28 in the first mixing junction 56 can help prevent the component feed system 40 from becoming clogged or needing to be cleaned, especially where the component feed system 40 may be delivering a dry component, such as particulate SAM.

[0360] Additionally or alternatively, the pressure control system 50 can be configured to provide additional positive pressure to prevent back-filling of the component feed system 40 in some circumstances, such as if a downstream obstruction occurs in the apparatus 11 beyond the first mixing junction 56. In such a case of an obstruction creating an increased pressure, the second fluid supply 28 may have a desire to back-fill the component feed system 40. Back-filling of fluid into the component feed system 40 can be detrimental to processing, especially where the supply of the component 44 is a component best kept in dry conditions, such as SAM. A pressure control system 50 configured to be able to provide positive pressure to the component feed system 40 can help prevent such back-filling of the component feed system 40.

[0361] It is also contemplated that other additional aspects of a pressure control system 50 could be utilized to maintain the pressure to a suitable level for the component feed system 40, including, but not limited to, supplying vacuum to the component feed system 40 in addition to or alternative to the air bleed-in at the bleed orifice 54 and / or the positive pressure described above.

[0362] The first mixing junction 56 can also provide pressure control on the transfer of the second fluid supply 28 including the component 44 as it exits the discharge 64 of the first mixing junction 56 as compared to when the second fluid supply 28 enters the first mixing junction 56. The second fluid supply 28 can be transferred at a second fluid pressure prior to the first mixing junction 56. The second fluid supply 28 including the component from the supply of the component 44 can exit the discharge 64 of the first mixing junction 56 at a discharge pressure. The pressure difference between the second fluid pressure prior to the first mixing junction 56 and the discharge pressure can be controlled. In some embodiments, this pressure difference can be controlled by varying the flow rate of the second fluid supply 28 or through the positioning of the outlet conduit 46 in the first mixing junction 56. In some embodiments, it is preferable to control the pressure difference between the second fluid pressure prior to the first mixing junction 56 and the discharge pressure to be less than or equal to 5 pounds per square inch.

[0363] It is to be noted that while a single outlet conduit 46 of the component feed system 40 and a single first mixing junction 56 is illustrated in FIG. 3, it is contemplated that the outlet conduit 46 can be split into two or more conduits to feed two or more first mixing junctions 56 for mixing the supply of the component 44 with the second fluid supply 28. In such a configuration, the second fluid supply 28 can65119655PCT04 KCX-2169-PCT

[0364] include as many conduits as there are first mixing junctions 56. By having more than one outlet conduit 46 and more than one first mixing junction 56 to mix the supply of the component 44 with the second fluid supply 28, a greater flow rate of the second fluid supply 28 including the component from the supply of the component 44 can be achieved.

[0365] Referring to FIG. 3, the apparatus 11 can include a second mixing junction 58 in some embodiments. The second mixing junction 58 can provide the functionality of mixing the second fluid supply 28 including the component from the supply of the component 44 with the first fluid supply 16.

[0366] As the second fluid supply 28 including the component from the supply of the component 44 exits the discharge 64 of the first mixing junction 56 it can be transferred to the second mixing junction 58. The first fluid supply 16 can be delivered to the second mixing junction 58 by the first pump 36. The second mixing junction 58 can mix the first fluid supply 16 and any of its components (e.g., fluid 18, fibers 20, foaming surfactant 22) with the second fluid supply 28 and any of its components (e.g., fluid 30, foaming surfactant 32) and the component from the supply of the component 44 to deliver the mixture of the first fluid supply 16, the second fluid supply 28, and the component 44 to a headbox 80.

[0367] Alternatively, in some embodiments, a second mixing junction 58 can be omitted from the apparatus 11 and the second fluid supply 28 including the component from the supply of the component 44 can be delivered to headbox 80.

[0368] As illustrated in FIGS. 4 and 5, the headbox 80 can include one or more z-directional dividers 78a, 78b for separating different inputs to the headbox 80 in forming different layers of the nonwoven material 10. The third fluid supply 33 and any of its components (e.g., fluid 35, fibers 37, foaming surfactant 39) can be delivered to the inlet 81 of the headbox 80 via the third pump 43 and can be delivered above the first z-directional divider 78a in a first z-directional zone 85a of the headbox 80.

[0369] The output of the second mixing junction 58 including the mixture of the first fluid supply 16 and any of its components (e.g., fluid 18, fibers 20, foaming surfactant 22), the second fluid supply 28 and any of its components (e.g., fluid 30, foaming surfactant 32), and the component 44 can be delivered to the inlet 81 of the headbox 80 below the first z-directional divider 78a and above the second z-directional divider 78b in a second z-directional zone 85b of the headbox 80. The fourth fluid supply 68 and any of its components (e.g., fluid 69, fibers 70, foaming surfactant 71) can be delivered to the inlet 81 of the headbox 80 via the fourth pump 73 and can be delivered below the second z-directional divider 78b in a third z-directional zone 85c of the headbox 80. Such a configuration of two z-directional dividers 78a, 78b can be beneficial for forming a three-layered substrate 10, such as described above and illustrated in FIG. 2.65119655PCT04 KCX-2169-PCT

[0370] The headbox 80 can provide a resultant slurry 76 to a forming surface 94. The forming surface 94 can be a foraminous sheet, such as a woven belt or screen, or any other suitable surface for accepting the resultant slurry 76.

[0371] The apparatus 11 can also include a dewatering system 96 that can be configured to remove liquid from the resultant slurry 76 (e.g ., forming fluid) on the forming surface 94. In some embodiments, the dewatering system 96 can be configured to provide a vacuum to the resultant slurry 76 to pull liquid from the resultant slurry 76, and in doing so, can turn the resultant slurry 76 including the plurality of fibers 20 and the component 44, if present, into a multi-layer substrate 10. In some embodiments, the dewatering system 96 can begin dewatering on fibers and / or components as they are still within the headbox 80.

[0372] Dewatering systems 96 drawing liquid from the resultant slurry 76 can also unintentionally draw components 44 (such as particulate SAM) through the forming surface 94, and / or cause components 44 to become lodged in the forming surface 94. Not only can this cause substrates 10 to be formed that do not include intended amounts of the component 44, but components 44 becoming lodged in the forming surface 94 and / or being drawn through the forming surface 94 can cause processing issues, including, but not limited to, reduced dewatering and / or increased demands for drying of the resultant slurry 76, machine down-time for cleaning, and increased complexity for dewatered liquid by including such components 44. Forming a multi-layer substrate 10 including components 44 in a fluid, such as foam forming, can exacerbate the problem of component 44 movement in the resultant slurry 76 in comparison to dry forming techniques, such as air-laid formation techniques or adhesive-based techniques.

[0373] Forming a distribution layer 17 as part of the substrate 10 that is directly against the forming surface 94 can help protect the components 44 of the substrate 12 (such as SAM in the retention layer 13). The distribution layer 17 can protect the components 44 of the substrate 10 from the forming surface to help ensure the components 44 remain in the substrate 10, or at least reduce the possibility for the components 44 to become lodged in the forming surface 94 or be drawn through the forming surface 94. Additionally, the distribution layer 17 can help retain components 44 within the absorbent material 10 as it is potentially transported for further processing and / or use in other products in which the multi-layer substrate 10 may be incorporated within, such as personal care absorbent articles. Forming the distribution layer 17 inline as a composite with the retention layer 13 where at least some fibers of the distribution layer 17 are mixed with at least some of the fibers of the retention layer 13 at the interface 19, eliminates the need for additional processing to form a composite absorbent substrate 10, such as the use of adhesive to couple a separate distribution layer 17 to a retention layer 13.65119655PCT04 KCX-2169-PCT

[0374] Eliminating adhesive can result in reduced processing equipment and raw material cost and can also lead to improved fluid handling properties of the absorbent substrate 10. Additionally, forming a distribution layer 17 as part of the substrate 10 can also provide improved integrity and tensile strength for the absorbent material 10 providing enhanced processing capability of the substrate 10.

[0375] As shown in FIG. 3, after the dewatering system 96, the web making process includes a surfactant applicator 97 followed by a drying system 98. In accordance with the present disclosure, a surfactant composition is applied to the absorbent substrate 10 prior to drying the absorbent substrate and / or prior to activating binder fibers contained within the substrate. The surfactant applicator 97, for instance, can be designed to spray a surfactant composition containing at least one surfactant onto the absorbent substrate 10 over substantially the entire surface of the substrate. In one aspect, the surfactant composition is applied to the absorbent substrate 10 while the absorbent substrate 10 contains moisture in an amount greater than about 8% by weight, such as in an amount greater than about 10% by weight, such as in an amount greater than about 15% by weight, such as in an amount greater than about 20% by weight, such as in an amount greater than about 25% by weight, such as in an amount greater than about 30% by weight, and in an amount less than about 60% by weight, such as in an amount less than about 50% by weight, such as in an amount less than about 40% by weight, such as in an amount less than about 35% by weight.

[0376] If desired, the absorbent substrate 10 can be partially dried after being dewatered prior to application of the surfactant composition. In one aspect, however, the surfactant composition is applied prior to any substantial bonding of the binder fibers contained in the absorbent substrate. For instance, the surfactant composition can be applied to the absorbent substrate 10 prior to the absorbent substrate being heated to a temperature above the bonding temperature of the binder fibers. For example, the surfactant composition can be applied to the absorbent substrate 10 prior to the absorbent substrate 10 being heated to a temperature above about 80°C, such as above about 90°C, such as above about 100°C, such as above about 110°C. The bonding temperature of the binder fibers depends upon the polymers used to construct the binder fibers.

[0377] The apparatus 11 further includes the drying system 98 to dry the absorbent substrate 10 and / or to activate the binder materials contained within the substrate. The drying system 98, in one embodiment, can comprise a through-air dryer. The through-air dryer, for instance, can apply heat to the absorbent material 10 by passing heated air through the substrate.

[0378] In some embodiments, the apparatus 11 can include a winding system 99 (as shown in FIG.

[0379] 3) that can be configured to wind the absorbent material 10 in a roll fashion. In other embodiments,65119655PCT04 KCX-2169-PCT

[0380] the apparatus 11 can festoon the absorbent material 10 or collect the absorbent material 10 in any other suitable configuration, such as spooling.

[0381] It should be understood that FIG. 3 is one exemplary embodiment for forming an absorbent substrate 10 in accordance with the present disclosure. Any suitable wetlaid system may be used. For instance, alternatively, a vertical twin former can be used to form the multi-layer substrate.

[0382] As described above, the foam forming processes as described herein can include a foaming fluid. In some embodiments, the foaming fluid can comprise between about 85% to about 99.99% of the foam (by weight). In some embodiments, the foaming fluid used to make the foam can comprise at least about 85% of the foam (by weight). In certain embodiments, the foaming fluid can comprise between about 90% and about 99.9% % of the foam (by weight). In certain other embodiments, the foaming fluid can comprise between about 93% and 99.5% of the foam or even between about 95% and about 99.0% of the foam (by weight). In preferred embodiments, the foaming fluid can be water, however, it is contemplated that other processes may utilize other foaming fluids.

[0383] The foam forming processes as described herein can utilize one or more foaming surfactants. The fibers and foaming surfactant, together with the foaming liquid and any additional components, can form a stable dispersion capable of substantially retaining a high degree of porosity for longer than the drying process. In this regard, the foaming surfactant is selected so as to provide a foam having a foam half life of at least 2 minutes, more desirably at least 5 minutes, and most desirably at least 10 minutes. A foam half life can be a function of foaming surfactant types, surfactant concentrations, foam compositions / solid level and mixing power / air content in a foam. The foaming surfactant used in the foam can be selected from one or more known in the art that are capable of providing the desired degree of foam stability. In this regard, the foaming surfactant can be selected from anionic, cationic, nonionic and amphoteric surfactants provided they, alone or in combination with other components, provide the necessary foam stability, or foam half life. As will be appreciated, more than one foaming surfactants can be used, including different types of surfactants, as long as they are compatible, and more than one foaming surfactant of the same type. For example, a combination of a cationic foaming surfactant and a nonionic foaming surfactant or a combination of an anionic foaming surfactant and a nonionic foaming surfactant may be used in some embodiments due to their compatibilities. However, in some embodiments, a combination of a cationic foaming surfactant and an anionic foaming surfactant may not be satisfactory to combine due to incompatibilities between the surfactants. In one aspect, a primary foaming surfactant may be used to produce a foam and a secondary foaming surfactant can be applied to the nonwoven material during processing.65119655PCT04 KCX-2169-PCT

[0384] Anionic foaming surfactants believed suitable for use with the present disclosure include, without limitation, anionic sulfate surfactants, alkyl ether sulfonates, alkylaryl sulfonates, or mixtures or combinations thereof. Examples of alkylaryl sulfonates include, without limitation, alkyl benzene sulfonic acids and their salts, dialkylbenzene disulfonic acids and their salts, dialkylbenzene sulfonic acids and their salts, alkylphenol sulfonic acids / condensed alkylphenol sulfonic acids and their salts, or mixture or combinations thereof. Examples of additional anionic foaming surfactants believed suitable for use in the present disclosure include alkali metal sulforicinates, sulfonated glyceryl esters of fatty acids such as sulfonated monoglycerides of coconut oil acids, salts of sulfonated monovalent alcohol esters such as sodium oleylisethianate, metal soaps of fatty acids, amides of amino sulfonic acids such as the sodium salt of oleyl methyl tauride, sulfonated products of fatty acids nitriles such as palmitonitrile sulfonate, alkali metal alkyl sulfates such as sodium lauryl sulfate, ammonium lauryl sulfate or triethanolamine lauryl sulfate, ether sulfates having alkyl groups of 8 or more carbon atoms such as sodium lauryl ether sulfate, ammonium lauryl ether sulfate, sodium alkyl aryl ether sulfates, and ammonium alkyl aryl ether sulfates, sulphuric esters of polyoxyethylene alkyl ether, sodium salts, potassium salts, and amine salts of alkylnapthylsulfonic acid. Certain phosphate foaming surfactants including phosphate esters such as sodium lauryl phosphate esters or those available from the Dow Chemical Company under the tradename TRITON are also believed suitable for use herewith. A particularly desired anionic foaming surfactant is sodium dodecyl sulfate (SDS).

[0385] Cationic foaming surfactants are also believed suitable for use with the present disclosure for manufacturing some embodiments of substrates. In some embodiments, such as those including superabsorbent material, cationic foaming surfactants may be less preferable to use due to potential interaction between the cationic foaming surfactant(s) and the superabsorbent material, which may be anionic. Foaming cationic surfactants include, without limitation, monocarbyl ammonium salts, dicarbyl ammonium salts, tricarbyl ammonium salts, monocarbyl phosphonium salts, dicarbyl phosphonium salts, tricarbyl phosphonium salts, carbylcarboxy salts, quaternary ammonium salts, imidazolines, ethoxylated amines, quaternary phospholipids and so forth. Examples of additional cationic foaming surfactants include various fatty acid amines and amides and their derivatives, and the salts of the fatty acid amines and amides. Examples of aliphatic fatty acid amines include dodecylamine acetate, octadecylamine acetate, and acetates of the amines of tallow fatty acids, homologues of aromatic amines having fatty acids such as dodecylanalin, fatty amides derived from aliphatic diamines such as undecylimidazoline, fatty amides derived from aliphatic diamines such as undecylimidazoline, fatty amides derived from disubstituted amines such as oleylaminodiethylamine, derivatives of ethylene diamine, quaternary ammonium compounds and their salts which are exemplified by tallow trimethyl65119655PCT04 KCX-2169-PCT

[0386] ammonium chloride, dioctadecyldimethyl ammonium chloride, didodecyldimethyl ammonium chloride, dihexadecyl ammonium chloride, alkyltrimethylammonium hydroxides, dioctadecyldimethylammonium hydroxide, tallow trimethylammonium hydroxide, trimethylammonium hydroxide, methylpolyoxyethylene cocoammonium chloride, and dipalmityl hydroxyethylammonium methosulfate, amide derivatives of amino alcohols such as beta-hyd roxylethy Istearylamide, and amine salts of long chain fatty acids. Further examples of cationic foaming surfactants believed suitable for use with the present disclosure include benzalkonium chloride, benzethonium chloride, cetrimonium bromide, distearyldimethylammonium chloride, tetramethylammonium hydroxide, and so forth.

[0387] Nonionic foaming surfactants believed suitable for use in the present disclosure include, without limitation, condensates of ethylene oxide with a long chain fatty alcohol or fatty acid, condensates of ethylene oxide with an amine or an amide, condensation products of ethylene and propylene oxides, fatty acid alkylol amide and fatty amine oxides. Various additional examples of nonionic foaming surfactants include stearyl alcohol, sorbitan monostearate, octyl glucoside, octaethylene glycol monododecyl ether, lauryl glucoside, cetyl alcohol, cocamide MEA, monolaurin, polyoxyalkylene alkyl ethers such as polyethylene glycol long chain (12-14C) alkyl ether, polyoxyalkylene sorbitan ethers, polyoxyalkylene alkoxylate esters, polyoxyalkylene alkylphenol ethers, ethylene glycol propylene glycol copolymers, polyvinyl alcohol, alkylpolysaccharides, polyethylene glycol sorbitan monooleate, octylphenol ethylene oxide, and so forth. Non-ionic foaming surfactants may be preferable when foam forming absorbent materials 10 with SAM. If there is residual ionic foaming surfactant, the increase in ionic strength in the insult can reduce SAM swelling for use of the absorbent materials 10 in personal care absorbent articles.

[0388] The foaming surfactant can be used in varying amounts as necessary to achieve the desired foam stability and air-content in the foam. In certain embodiments, the foaming surfactant can comprise between about 0.005% and about 5% of the foam (by weight). In certain embodiments the foaming surfactant can comprise between about 0.05% and about 3% of the foam or even between about 0.05% and about 2% of the foam (by weight).

[0389] As noted above, the apparatus 11 and methods described herein can include providing a fibers from a supply of fibers 20, 37, 70, 123, 125. In some embodiments, the fibers can be suspending in a fluid supply 16, 28, 33, 68 that can be a foam. The foam suspension of fibers can provide one or more supply of fibers. As described above, fibers utilized herein can include cellulose fibers and / or synthetic fibers. In some embodiments, a fiber supply 20, 37, 70, 123, 125 can include only cellulose fibers or only synthetic fibers. In other embodiments, a fiber supply 20, 37, 70, 123, 125 can include a mixture of cellulose fibers, binder fibers and / or synthetic fibers. Some fibers being65119655PCT04 KCX-2169-PCT

[0390] utilized herein can be absorbent, whereas other fibers utilized herein can be non-absorbent. Nonabsorbent fibers can provide features for the substrates that are formed from the methods and apparatuses described herein, such as improved intake or distribution of fluids.

[0391] In some embodiments, a fluid supply 16, 28, 33, 68 can include binder fibers (as described above) that can be provided along with or independent of the supply of the fibers 20, 37, 70, 123, 125 or the supply of the component 44.

[0392] Binder fibers, when used, may be added proportionally to the other components to achieve the desired fiber ratios and structure while maintaining the total solids content of the foam below the amounts stated above. As an example, in some embodiments, binder fibers can comprise between about 0% and about 80% of the total fiber weight, and more preferably, between about 5% to about 40% of the total fiber weight in some embodiments.

[0393] In some embodiments, if a fluid supply 16, 28, 33, 68 is configured as a foam the foam may optionally also include one or more foam stabilizers known in the art and that are compatible with the components of the foam and further do not interfere with the hydrogen bonding as between the cellulosic fibers. Foam stabilizing agents believed suitable for use in the present disclosure, without limitation, one or more zwitterionic compounds, amine oxides, alkylated polyalkylene oxides, or mixture or combinations thereof. Specific examples of foam stabilizers includes, without limitation, cocoamine oxide, isononyldimethylamine oxide, n-dodecyldimethylamine oxide, and so forth.

[0394] In some embodiments, if utilized, the foam stabilizer can comprise between about 0.01% and about 2 % of the foam (by weight). In certain embodiments, the foam stabilizer can comprise between about 0.05% and 1% of the foam or even between about 0.1 and about 0.5% of the foam (by weight).

[0395] As mentioned above, foam forming processes can include adding one or more components 44 as additional additives that will be incorporated into the absorbent material 10, such as SAM. In some embodiments incorporating SAM, the SAM can comprise between about 0% and about 40% of the foam (by weight). In certain embodiments, SAM can comprise between about 1% and about 30% of the foam (by weight) or even between about 10% and about 30% of the foam (by weight).

[0396] If used, wet and dry strength additives can comprise between about 0.01 and about 5% of the dry weight of cellulose fibers. In certain embodiments, the strength additives can comprise between about 0.05% and about 2% of the dry weight of cellulose fibers or even between about 0.1 % and about 1 % of the dry weight of cellulose fibers.

[0397] When employed, miscellaneous components that may also be used in the absorbent material (as described above, such as, pigments, anti-microbial agents, etc.) can desirably comprise less than65119655PCT04 KCX-2169-PCT

[0398] about 2% of the foam (by weight) and still more desirably less than about 1 % of the foam (by weight) and even less than about 0.5% of the foam (by weight).

[0399] In some embodiments, the solids content, including the fibers or particulates contained herein, desirably comprise no more than about 40% of the foam. In certain embodiments the cellulosic fibers can comprise between about 0.1% and about 5% of the foam or between about 0.2 and about 4% of the foam or even between about 0.5% and about 2% of the foam.

[0400] The nonwoven webs or absorbent substrates as described above can be incorporated into numerous different absorbent articles including the feminine hygiene products as shown in FIG. 1 In one aspect, the absorbent substrate incorporated into products of the present disclosure are relatively thin while having excellent absorbency properties. For instance, the absorbent substrate can have a thickness of less than about 8 mm, such as less than about 7 mm, such as less than about 6 mm, such as less than about 5 mm, such as less than about 4.5 mm, such as less than about 4 mm.

[0401] In addition to having excellent fluid handling properties, the absorbent article can be very flexible. For instance, when tested according to the Horizontal Side Compression Test, the absorbent article can display an energy after one cycle of less than of less than about 2,000 gfcm, such as less than about 1 ,600 gfcm, such as less than about 1 ,500 gfcm, such as less than about 1 ,200 gfcm, such as less than about 1,000 gfcm. The absorbent article can display a width recovery of greater than about 80%, such as greater than about 82%, such as greater than about 84%, such as greater than about 85%, and less than about 99%.

[0402] The present disclosure may be better understood with reference to the following examples.

[0403] Example No. 1

[0404] In the example below, a multi-layer nonwoven material or absorbent substrate was produced. The multi-layer absorbent substrate was produced using a foam forming process as described above. The absorbent substrate that was produced contained a top intake layer, a center retention layer, and a bottom distribution layer. The top intake layer only contained synthetic polymer fibers combined with binder fibers. In accordance with the present disclosure, a surfactant composition containing a blend of an anionic surfactant and a nonionic surfactant (50:50 weight ratio) was applied to the absorbent substrate prior to being fed to a through-air dryer and dried and bonded (Sample No. 1). For purposes of comparison, the same surfactant composition in the same amount was applied to an identical absorbent substrate after the substrate was dried and bonded (Sample No. 2).

[0405] The surfactant composition contained 50% by weight SILASTOL 163 surfactant sold by Schill and Seilacher and 50% by weight CIRRASOL PP862 sold by Croda International. The surfactants were applied to the absorbent substrate in an amount of 0.3 gsm.65119655PCT04 KCX-2169-PCT

[0406] The following absorbent substrates were produced:Table 1

[0407]

[0408] 65119655US01 KCX-2168-P

[0409] The samples above were subjected to the Cut Cradle Test (38 ml insult) and also the Surfactant Penetration Quantification Test. The following results were obtained:

[0410] Table No. 2: Cut Cradle Test

[0411]

[0412] As shown above, the absorbent substrate made in accordance with the present disclosure displayed dramatically better Cut Cradle Test results than the absorbent substrate that was treated with the surfactant after drying and bonding.

[0413] The two samples above were also subjected to the Surfactant Penetration Quantification Test. During the test, sulfur was detected in the Z-direction of the substrate. For Sample No. 1 , sulfur was detected at a higher concentration in the surface compared to the rest of the sample. The sulfur concentration then dissipated through the cross-section of the sample indicating a gradient of sulfur distribution within the material. The amount of sulfur detected was above the detection limits of the instrument.

[0414] In stark contrast, Sample No. 2 was below the limits of detection for the instrument indicating that sulfur was either absent or present at extremely low levels that could not be reliably measured.

[0415] Example No. 2

[0416] Multi-layer nonwoven materials or absorbent substrates were produced as described in Example No. 1. The multi-layer absorbent substrates were produced using a foam forming process as described above. Each absorbent substrate contained a top intake layer, a center retention layer, and a bottom distribution layer.

[0417] Three different absorbent substrates were produced having different basis weights and containing different amounts of superabsorbent material.

[0418] In accordance with the present disclosure, a surfactant composition containing sodium dioctyl sulfosuccinate (SILASTOL 163 sold by Schill) was applied to each absorbent substrate prior to being fed to a through-air dryer and dried and bonded (Sample Nos. 4, 6 and 8). For purposes of comparison, the same surfactant composition in the same amount was applied to an identical absorbent substrate after the substrate was dried and bonded (Sample Nos. 3, 5, and 7).

[0419] The surfactant composition was applied to each absorbent substrate in an amount of about 1 gsm (Sample Nos. 3 and 4) and 0.3 gsm (Sample Nos. 5-8).65119655US01 KCX-2168-P The following absorbent substrates were produced:

[0420] Sample Nos. 3 and 4

[0421]

[0422] Sample Nos. 5 and 6 had the same construction as Sample Nos. 1 and 2 in Example No. 1.

[0423]

[0424] 65119655US01 KCX-2168-P

[0425] Sample Nos. 7 and 8

[0426]

[0427] The above samples were subjected to the Surfactant Penetration Test and the following results were obtained:

[0428]

[0429] 65119655US01 KCX-2168-P

[0430]

[0431]

[0432]

[0433] 65119655US01 KCX-2168-P

[0434]

[0435] As shown above, much more surfactant stayed in the top 50% of the thickness of the substrates made in accordance with the present disclosure.

[0436] Sample Nos. 7 and 8 were also subjected to the Closed Cradle Test and the Cut Cradle Test (105 ml insult). The following results were obtained:

[0437]

[0438] 65119655US01 KCX-2168-P

[0439]

[0440] As shown above, the absorbent substrate made in accordance with the present disclosure displayed dramatically better Closed Cradle and Cut Cradle Test results than the absorbent substrate that was treated with the surfactant after drying and bonding.

[0441] These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention so further described in such appended claims.

Claims

65119655US01 KCX-2168-PWhat Is Claimed:

1. An absorbent and unitary substrate comprising:an intake layer containing binder fibers;a retention layer containing a superabsorbent material blended with fibers, and wherein at least some of the fibers of the intake layer are intermingled with at least some fibers of the retention layer;a surfactant composition comprising at least one surfactant present in the intake layer; and wherein the substrate displays a Cut Cradle 1st free fluid of less than about 15 g after a 38 ml insult2. An absorbent and unitary substrate as defined in claim 1 , further comprising a distribution layer, the retention layer being disposed between the intake layer and the distribution layer.

3. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the substrate displays a Cut Cradle 1stfree fluid of less than about 13 g, such as less than about 12 g, such as less than about 10 g, such as less than about 9 g, such as less than about 8 g after a 38 ml insult.

4. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the substrate displays a Cut Cradle 2ndfree fluid of less than about 4 g, such as less than about 3.5 g, such as less than about 3 g, such as less than about 25 g, such as less than about 2 g, such as less than about 1.5 g, such as less than about 1 g, such as less than about 0.5 g after two 38 ml insults.

5. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the intake layer comprises polymer synthetic fibers combined with the binder fibers.

6. An absorbent and unitary substrate as defined in claim 5, wherein the intake layer contains cellulose fibers in an amount less than about 5% by weight, such as in an amount less than about 1% by weight.

7. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the surfactant comprises a nonionic surfactant.8 An absorbent and unitary substrate as defined in any of claims 1-6, wherein the surfactant comprises an anionic surfactant.

9. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the surfactant composition comprises a nonionic surfactant combined with an anionic surfactant.

10. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the surfactants contained in the surfactant composition are applied to the intake layer in an amount less than about 1 gsm, such as in an amount less than about 0.8 gsm, such as in an amount less than about 0.6 gsm, such as in an amount less than about 0.4 gsm.65119655US01 KCX-2168-P11. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the substrate is foam formed.

12. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the superabsorbent material is contained in the retention layer at a basis weight of greater than about 150 gsm, such as greater than about 180 gsm, such as greater than about 190 gsm, and wherein the absorbent and unitary substrate has a basis weight of from about 250 gsm to about 1,300 gsm.

13. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the substrate displays a Cut Cradle 1st free fluid of less than about 30 g after a 105 ml insult and a 2ndfree fluid of less than 50 g, such as less than about 48 g after two 105 ml insults.

14. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the substrate displays a Closed Cradle 1stintake time of less than about 45 sec, such as less than about 40 sec, such as less than about 38 sec, displays a Closed Cradle 2nd intake time of less than about 150 sec, such as less than about 140 sec, such as less than about 130 sec, displays a Closed Cradle 3rd intake time of less than about 180 sec, such as less than about 170 sec, such as less than about 175 sec, and displays a rewet of less than about 0.6 g, such as less than about 0.5 g.

15. An absorbent and unitary substrate comprising:an intake layer containing binder fibers;a retention layer containing a superabsorbent material blended with fibers, and wherein at least some of the fibers of the intake layer are intermingled with at least some fibers of the retention layer;a surfactant composition comprising at least one surfactant, the surfactant composition being applied to the intake layer; andwherein, when tested according to the Surfactant Penetration Quantification Test, an identifying element indicates that at least about 42 %, such as at least about 44%, such as at least about 46% by weight of the surfactant remains in the top 50% of the thickness of the substrate.

16. An absorbent and unitary substrate as defined in claim 13, wherein the substrate displays a Cut Cradle 1stfree fluid of less than about 13 g, such as less than about 12 g, such as less than about 10 g, such as less than about 9 g, such as less than about 8 g after a 38 ml insult.

17. An absorbent and unitary substrate as defined in claim 13, wherein the substrate displays a Cut Cradle 2ndfree fluid of less than about 4 g, such as less than about 3.5 g, such as less than about 3 g, such as less than about 2.5 g, such as less than about 2 g, such as less than about 1.5 g, such as less than about 1 g, such as less than about 0.5 g after two 38 ml insults.

18. An absorbent and unitary substrate as defined in claim 13, wherein the intake layer comprises polymer synthetic fibers combined with the binder fibers.65119655US01 KCX-2168-P19. An absorbent and unitary substrate as defined in claim 16, wherein the intake layer contains cellulose fibers in an amount less than about 5% by weight, such as in an amount less than about 1% by weight.

20. An absorbent and unitary substrate as defined in claim 13, wherein the surfactant comprises a nonionic surfactant.

21. An absorbent and unitary substrate as defined in claim 13, wherein the surfactant comprises an anionic surfactant.

22. An absorbent and unitary substrate as defined in claim 13, wherein the surfactant composition comprises a nonionic surfactant combined with an anionic surfactant.

23. An absorbent and unitary substrate as defined in claim 13, wherein the surfactants contained in the surfactant composition are applied to the intake layer in an amount less than about 1 gsm, such as in an amount less than about 0.8 gsm, such as in an amount less than about 0.6 gsm, such as in an amount less than about 0.4 gsm.

24. An absorbent and unitary substrate as defined in claim 13, wherein the substrate is foam formed.

25. An absorbent and unitary substrate as defined in claim 13, wherein the superabsorbent material is contained in the retention layer at a basis weight of greater than about 150 gsm, such as greater than about 180 gsm, such as greater than about 190 gsm, and wherein the absorbent and unitary substrate has a basis weight of from about 250 gsm to about 1,300 gsm.

26. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the substrate displays a Cut Cradle 1st free fluid of less than about 30 g after a 105 ml insult and a 2nd free fluid of less than 50 g, such as less than about 48 g after two 105 ml insults.

27. An absorbent and unitary substrate as defined in any of the preceding claims, wherein the substrate displays a Closed Cradle 1st intake time of less than about 45 sec, such as less than about 40 sec, such as less than about 38 sec, displays a Closed Cradle 2nd intake time of less than about 150 sec, such as less than about 140 sec, such as less than about 130 sec, displays a Closed Cradle 3rd intake time of less than about 180 sec, such as less than about 170 sec, such as less than about 175 sec, and displays a rewet of less than about 0.6 g, such as less than about 0.5 g.

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