Process for producing absorbent substrates

Abstract

A process for producing nonwoven webs containing superabsorbent materials is disclosed. The webs are formed in a wet process, such as a foam forming process. During the process of making the nonwoven web, the time that the superabsorbent material is exposed to free water is minimized. In addition, superabsorbent materials are selected for use in the process that have slow water absorption kinetics at short contact time intervals while having high water absorption kinetics after prolonged contact time.

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application is related and has right of priority to U.S. Provisional Patent Application No. 63 / 609,919 filed on December 14,2023, which is incorporated by reference in its entireties for all purposes. BACKGROUND Many different types of nonwoven materials exist that are designed to have different functions. In many embodiments, the nonwoven materials are designed to have liquid handling properties. These nonwoven materials can be used in absorbent articles to absorb fluids. Absorbent articles, also referred to as personal care products, such as diapers, diaper inserts, diaper pants, training pants, adult incontinence products, and feminine hygiene products can include a variety of substrates. For example, absorbent articles can include an absorbent structure, nonwoven materials, and films. These layers are positioned relative to each other so that fluids coming into contact with the absorbent article are quickly drawn into the absorbent structure and contained in order to give the wearer a dry feel. Absorbent structures can contain a superabsorbent material. Superabsorbent materials can be configured in many forms including particles, granules, powder and fibers and are commonly utilized in substrates for increased absorbent capacity. Superabsorbent materials are substances capable of absorbing and retaining large amounts of liquid relative to their own mass. Superabsorbent materials, for instance, can be formed from hydrophilic polymers such as sodium polyacrylate, polyacrylamide, or cellulose-based polymers. In certain applications, the superabsorbent materials can be cross-linked which helps prevent the material from dissolving in water while allowing it to swell and hold a large amount of liquid. In forming layers or structures containing superabsorbent materials, the superabsorbent materials are typically applied onto a substrate or carrier material. The superabsorbent material can be in the form of a powder or in the form of granules. The substrate can be a nonwoven fabric, such as a tissue web. In order to form materials containing superabsorbent particles, in the past, many processes involved incorporating the superabsorbent materials into a substrate without allowing the superabsorbent materials to contact moisture or water. Handling and transporting the dry superabsorbent materials pose various problems and results in slower line speeds and inefficiencies. Producing substrates in a wet forming process can produce advantaged structures at faster speeds. Unfortunately, superabsorbent materials cannot be readily used in wet forming processes due to their excessive swelling and associated drying cost and challenges. In view of the above, a need exists for a process for forming a layer or web containing superabsorbent materials in a continuous process that can rapidly and efficiently form the web or layer. For instance, in one aspect, a need exists for a wet-forming process for forming webs or layers containing superabsorbent materials that is conducted in a manner such that the superabsorbent materials do not pick up substantial amounts of moisture that later need to be evaporated. SUMMARY The present disclosure is generally directed to an energy efficient process for producing nonwoven webs containing superabsorbent materials. More particularly, the process of the present disclosure is directed to a wet-forming process for producing nonwoven webs containing superabsorbent materials in which the amount of moisture absorbed by the superabsorbent materials during the process is minimized in order to reduce the energy needed to dry the materials after formation. In this manner, not only energy requirements are reduced in producing the nonwoven webs, but nonwoven webs can be made according to the present disclosure at relatively fast speeds. In one embodiment, for instance, the present disclosure is directed to a process for forming an absorbent structure. The process includes combining a superabsorbent material with a fluid supply. The fluid supply optionally comprises a plurality of fibers, such as cellulose fibers, entrained in an aqueous fluid. The superabsorbent material is mixed with the fluid supply to form a slurry. The resulting slurry is then transferred to a forming surface and drained of fluids (e.g. dewatered) to form a nonwoven web containing the superabsorbent material. In accordance with the present disclosure, prior to being transferred to the forming surface or drained of fluids, the superabsorbent material is in contact with the aqueous fluid for less than about 5 seconds, such as less than about 4 seconds, such as less than about 3 seconds, such as less than about 2 seconds. A superabsorbent material is selected for use in the process that displays a dynamic vapor sorption of less than about 3%, such as less than about 2.8%, such as less than about 2.5%, such as less than about 2.3%, such as less than about 2%, after 7 minutes when placed in an environment at 95% relative humidity and at a temperature of 35°C. The superabsorbent material is also selected such that the superabsorbent material displays a vortex time of less than about 55 seconds, such as less than about 50 seconds. After the slurry is drained of fluids, the nonwoven web is dried using any suitable drying device, such as a through-air dryer. In one aspect, the aqueous fluid comprises a foam. For instance, the aqueous fluid can comprise foam containing water, a surfactant, and optionally fibers, such as cellulose pulp fibers. In one embodiment, the superabsorbent material is combined with the fluid supply adjacent to a headbox that receives the slurry and transfers the slurry to the forming surface. Alternatively, the superabsorbent material can be combined with the fluid supply within the headbox. The superabsorbent material, for instance, can be in a dry state prior to contacting the fluid supply. In this manner, the amount of time the superabsorbent material contacts moisture is minimized. In fact, the superabsorbent material can be fed to the process in a dry state and can contact free water during the entire process for less than about 5 seconds, such as less than about 4 seconds, such as less than about 3 seconds, such as less than about 2 seconds. In one aspect, the aqueous fluid that contacts the superabsorbent material is at a relatively low temperature, such as at a temperature of less than about 20°C, such as less than about 18°C, such as less than about 15°C. Once the slurry is transferred to the forming surface, the slurry can be drained of fluids using, for instance, gravity and by applying a suction force to the slurry. The nonwoven web that is formed can have a basis weight of greater than about 50 gsm, such as greater than about 150 gsm, such as greater than about 200 gsm, such as greater than about 250 gsm, such as greater than about 300 gsm, such as greater than about 350 gsm, and less than about 800 gsm, such as less than about 600 gsm. The web can have a tensile strength in at least one direction of greater than about 700 gf / in, such as greater than about 1,000 gf / in, such as greater than about 1,200 gf / in, such as greater than about 1,500 gf / in, and less than about 15,000 gf / in. The nonwoven web made according to the present disclosure can comprise a single layer web or can comprise a multi-layer web. In one aspect, for instance, the nonwoven web can comprise a first layer, a second layer, and a third layer. The superabsorbent material can be contained in the second layer positioned between the first layer and the third layer. The nonwoven web can contain the superabsorbent material in an amount greater than about 10% by weight, such as in an amount greater than about 20% by weight, such as 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, 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, such as in an amount greater than about 90% by weight. In one aspect, the nonwoven web is made entirely from one or more superabsorbent materials. In one aspect, the nonwoven web contains the superabsorbent material combined with pulp fibers, synthetic polymer fibers, or mixtures thereof. In one embodiment, the process further comprises the step of cutting the nonwoven material or web into individual absorbent structures. The individual absorbent structures can then be incorporated into absorbent articles. The absorbent article, for instance, can comprise a diaper, a diaper insert, a child pant, a feminine hygiene product, an adult incontinence product, or the like. Other absorbent articles can also be constructed including bedmats. In one aspect, the absorbent article includes a fluid permeable liner, an outer cover, and an absorbent structure made in accordance with the present disclosure positioned between the liner and the outer cover. Other features and aspects of the present disclosure are discussed in greater detail below. BRIEF DESCRIPTION OF THE DRAWINGS 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: Figure 1 is a schematic diagram of one embodiment of a process that may be made to produce absorbent structures in accordance with the present disclosure; Figure 2 is another embodiment of a process that may be made to produce absorbent structures in accordance with the present disclosure; and Figure 3 is still another embodiment of a process that may be made to produce absorbent structures in accordance with the present disclosure. 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. DEFINITIONS 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. 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. 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. 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. As used herein, the term “layer” refers to a structure that provides an area of a substrate in a height direction of the substrate (e.g. z direction) that is comprised of similar components and structure. 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. 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. 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 contain 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. 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. 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. 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. The term "pulp" as used herein refers to fibers from natural sources such as woody and nonwoody 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. 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 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 / S19643 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, fiber-like 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 fiber length may be an arithmetic average, a length weighted average or a weight weighted average and may be expressed by the following equation: k (Xi *ni) / n where k=maximum fiber length XFfiber length nFnumber of fibers having length xi n=total number of fibers measured. 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 represents an average based on lengths of all different types, if any, of fibers in the sample. As used herein the term "staple fibers" means discontinuous fibers made from synthetic polymers or regenerated cellulose, such as polypropylene, polyethylene, post consumer recycle (PCR) fibers, polyester, nylon, viscose, rayon, and the like. Staple fibers may be cut fibers or the like. Staple fibers can have configurations that are bicomponent, multicomponent, shaped cross sections (e.g. round or flat), hollow, or the like. 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 130°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. The 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. As used herein, “synthetic polymer fibers” refers to fibers made from polymers. 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. As used herein, the “dynamic vapor sorption” test is conducted by employing a commercial DVS Adventure system from Surface Measurement Systems LTD, NA (https: / / www.surfacemeasurementsystems.com / ). In a typical experiment, the DVS Adventure system is pre-conditioned to desired experiment temperature for at least overnight (e.g. 12 hours to 24 hours) so that the temperature of the measurement chamber and also water reservoir for moisture generation can be fully stabilized. The carrier gas used by DVS Adventure system for moisture generation is dried through a Parker Balston Model 76-01 compressed through air dryer. In a DVS experiment, a sample of -10-25 mg of superabsorbent particles (full cut of particle sizes or a desired particle size range such as 300 micirons to 600 microns) is loaded into a sample pan (~ 9 mm in diameter) and then first dried in DVS Adventure’s sample chamber under 60 °C and zero relative humidity for 4 hours and then cooled back down to 35 °C in 2 hours under zero relative humidity. The dried sample is then exposed to targeted 95% relative humidity (e.g. RH 95%) under 35 °C for desired testing times such as 4 mins to 8 hours or 24 hours. The above described drying, cooling, and moisture exposure steps are all performed by using DVS Adventure system’s control software (version 1,3,4,0) in successive steps and the drying or moisture intake induced sample weight changes (e.g. absolute mass), mass percentage changes (dm%), and mass change rate or moisture intake rate (dm / dt, % / min) are continuously recorded. The recorded DVS Adventure original data files can then be converted to Excel files by using DVS Data Plot manager for analyzing differences among different SAM samples. As used herein, the “Vortex Test” is the amount of time in seconds required for 2 grams mass of superabsorbent particles to close a vortex created by stirring 50 milliliters of 0.9 percent by weight sodium chloride solution at 600 revolutions per minute on a magnetic stir plate. The time it takes for the vortex to close is an indication of the free swell absorbing rate of the particles. The vortex time test can be performed at a temperature is 23°C. and relative humidity of 50% according to the following procedure: (1) Measure 50 milliliters (±0.01 milliliter) of 0.9 percent by weight sodium chloride solution into the 100-milliliter beaker. (2) Place a 7.9 millimeters^ millimeters TEFLON® covered magnetic stir bar without rings (such as that commercially available under the trade designation S / P® brand single pack round stirring bars with removable pivot ring) into the beaker. (3) Program a magnetic stir plate (such as that commercially available under the trade designation DATAPLATE® Model #721) to 600 revolutions per minute. (4) Place the beaker on the center of the magnetic stir plate such that the magnetic stir bar is activated. The bottom of the vortex should be near the top of the stir bar. The superabsorbent particles are pre-screened through a U.S. standard #30 mesh screen (0.595 millimeter openings) and retained on a U.S. standard #50 mesh screen (0.297 millimeter openings). (5) Weigh out the required mass of the superabsorbent particles to be tested on weighing paper. (6) While the sodium chloride solution is being stirred, quickly pour the absorbent polymer to be tested into the saline solution and start a stopwatch. The superabsorbent particles to be tested should be added to the saline solution between the center of the vortex and the side of the beaker. (7) Stop the stopwatch when the surface of the saline solution becomes flat and record the time. The time, recorded in seconds, is reported as the vortex time. As used herein, the “bulk density” of a superabsorbent material is measured as follows. About 100 g of the superabsorbent polymer is placed in a funnel-shaped bulk density tester and flown down into a 100 ml container. Then, the weight of the superabsorbent polymer contained in the container is measured. The bulk density is calculated as (superabsorbent polymer weight) / (container volume, 100 ml), (unit: g / ml). DETAILED DESCRIPTION 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. 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 all wet-laid manufacturing processes. 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. 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. In general, the present disclosure is directed to an energy efficient wet forming process for producing absorbent structures containing a superabsorbent material. Attempting to produce absorbent structures containing a superabsorbent material in a wet forming process can be problematic. The superabsorbent materials, for instance, can readily pick up moisture during the process. Most or all of this moisture then needs to be evaporated to create the final product. Superabsorbent materials can absorb large quantities of moisture very quickly leading to processes that are not only slow but also require high energy requirements in order to dry the material after formation. The present disclosure, however, is directed to minimizing the amount of moisture absorbed by the superabsorbent material during the wet forming process. In order to form absorbent structures in accordance with the present disclosure, in one aspect, the wet forming process is configured such that the superabsorbent material only contacts free moisture for a very limited amount of time in order to limit the amount of moisture that is absorbed by the material. For instance, in one embodiment, the superabsorbent material is fed to the process in a dry state and contacts free water during the process for less than about 5 seconds in order to form a nonwoven material and begin the draining or dewatering process. For instance, the process can be operated such that the superabsorbent material contacts free water for less than about 4 seconds, such as less than about 3 seconds, such as less than about 2 seconds prior to draining or dewatering or being placed on a forming surface during the process. In addition to limiting the contact time between the superabsorbent material and free water, the process of the present disclosure also is directed to using superabsorbent materials that have particular water absorbency characteristics. Superabsorbent materials are selected for use in the process that are relatively slow to pick up moisture during initial exposure to water in the forming process but which also are very well adapted to absorbing great amounts of moisture over a time scale that is relevant to a use in a product, such as when being exposed to a fluid for a time of from about 10 seconds to a few minutes. It was unexpectedly discovered that the moisture absorbency characteristics of a superabsorbent material between the first few seconds after contact with moisture and after a greater period of time in contact with moisture are unrelated and unpredictable. In accordance with the present disclosure, superabsorbent materials are selected that have seemingly contradictory characteristics in that the superabsorbent materials do not absorb great amounts of moisture in short periods of time but are capable of absorbing great amounts of moisture when in contact with the moisture for periods of time of greater than about 5 seconds, such as greater than about 10 seconds, such as greater than about 20 seconds. In this regard, superabsorbent materials are selected for use in the process of the present disclosure that display a relatively low dynamic vapor sorption in combination with displaying a relatively short vortex time. The dynamic vapor sorption test, for instance, indicates the ability or characteristics of a superabsorbent material to absorb moisture during relatively short contact times. For example, in one aspect, the test is conducted by placing a dry and conditioned superabsorbent material into an environment at 95% relative humidity and at a temperature of 35°C for a determined period of time, such as 7 minutes, and measuring the amount of moisture absorbed. Absorbing lower amounts of moisture indicates that the superabsorbent material does not readily absorb moisture during initial contact with water. The Vortex Test, on the other hand, is better for determining the long term absorbency and retention properties of superabsorbent materials when contacted with free water or aqueous solutions. During the Vortex Test, a superabsorbent material is added to a stirred sodium chloride solution and the time it takes for the superabsorbent material to close a vortex is recorded. Although the Vortex Test and the Dynamic Vapor Sorption Test both provide information about the absorbency characteristics of the superabsorbent material, it was discovered that both tests identify different water absorption properties of the materials that have been found to be somewhat unrelated. In accordance with the present disclosure, a superabsorbent material is selected (and / or adjusted) such that the superabsorbent material not only displays a relatively low dynamic vapor sorption result, which indicates that the material does not experience rapid moisture absorption during short contact times, but also has a relatively short vortex time, which indicates that the superabsorbent material can reach maximum moisture absorbency very quickly. In other words, the superabsorbent material selected for use in the process of the present disclosure displays relatively slow water absorption kinetics at short moisture contact times while also displays fast swell moisture kinetics during periods of time more related to end use conditions. The superabsorbent material can be in the form of particles (e.g. granules, powder, fibers, etc.). The superabsorbent particles can be formed from a three-dimensional crosslinked polymer network that contains repeating units derived from one or more ethylenically (e.g., monoethylenically) unsaturated monomeric compounds having at least one hydrophilic radical, such as a carboxyl, carboxylic acid anhydride, carboxylic acid salt, sulfonic acid, sulfonic acid salt, hydroxyl, ether, amide, amino, or quaternary ammonium salt group. Particular examples of suitable ethylenically unsaturated monomeric compounds for forming the superabsorbent particles include, for instance, carboxylic acids (e.g., (meth)acrylic acid (encompasses acrylic acid and / or methacrylic acid), maleic acid, fumaric acid, cratonic acid, sorbic acid, itaconic acid, cinnamic acid, etc.); carboxylic acid anhydrides (e.g., maleic anhydride); salts (alkali metal salts, ammonium salts, amine salts, etc.) of carboxylic acids (e.g., sodium (meth)acrylate, trimethylamine(meth)acrylate, triethanolamine-(meth)acrylate, sodium maleate, methylamine maleate, etc.); vinyl sulfonic acids (e.g., vinylsulfonic acid, allyl sulfonic acid, vinyltoluenesulfonic acid, styrene sulfonic acid, etc.); (meth)acrylic sulfonic acids (e.g., sulfopropyl (meth)acrylate, 2-hydroxy-3-(meth)acryloxy propyl sulfonic acid, etc.); salts of vinyl sulfonic acids or (meth)acrylic sulfonic acids; alcohols (e.g., (meth)allyl alcohol); ethers or esters of polyols (e.g., hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, triethylene glycol (meth)acrylate, poly(oxyethylene oxypropylene) glycol mono (meth)allyl ether (in which hydroxyl groups may be etherified or esterified), etc.); vinylformamides; (meth)acrylamides, N-alkyl (meth)acrylamides (e.g., N-methylacrylamide, N-hexylacrylamide, etc.), N,N-dialkyl (meth)acrylamides (e.g., N,N-dimethylacrylamide, N,N-di-n-propylacrylamide, etc.); N-hydroxyalkyl (meth)acrylamides (e.g., N-methylol(meth)acrylamide, N-hydroxyethyl-(meth)acrylamide, etc.); N,N-dihydroxyalkyl (meth)acrylamides (e.g., N,N-dihydroxyethyl(meth)acrylamide); vinyl lactams (e.g., N-vinylpyrrolidone); amino group-containing esters (e.g., dialkylaminoalkyl esters, dihydroxyalkylaminoalkyl esters, morpholinoalkyl esters, etc.) of carboxylic acids (e.g., dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, morpholinoethyl (meth)acrylate, dimethylaminoethyl fumarate, etc.); heterocyclic vinyl compounds (e.g., 2-vinyl pyridine, 4-vinyl pyridine, N-vinyl pyridine, N-vinyl imidazole), etc.); quaternary ammonium salt group-containing monomers (e.g., N,N,N-trimethyl-N-(meth)acryloyloxyethylammonium chloride, N,N,N-triethyl-N-(meth)acryloyloxyethylammonium chloride, 2-hydroxy-3-(meth)acryloyloxypropyl trimethyl ammonium chloride, etc.); and so forth, as well as combinations of any of the foregoing. In one aspect, (meth)acrylic acid monomeric compounds, as well as salts thereof, are employed to form the superabsorbent particles. The monomeric compounds referenced above are generally soluble in water. It should be understood, however, that compounds may also be employed that can become water-soluble through hydrolysis. Suitable hydrolyzable monomers may include, for instance, ethylenically unsaturated compounds having at least one hydrolyzable radical, such as esters, amide and nitrile groups. Particular examples of such hydrolysable monomers include methyl (meth)acrylate, ethyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, vinyl acetate, (meth)allyl acetate, (meth)acrylonitrile, etc. Furthermore, it should be understood that additional monomers may be employed so that the resulting particles are formed as a copolymer, such as a random, grafted, or block copolymer. If desired, the comonomer(s) may be selected from the group of monomers listed above. For instance, the comonomer(s) may be (meth)acrylic acid, salt of (meth)acrylic acid, maleic acid anhydride, etc. In one particular embodiment, for example, a copolymer may be formed from acrylic acid (or a salt thereof) and maleic anhydride. In other embodiments, as described in more detail below, a comonomer may also be employed that contains a crosslinkable functionality, such as an alkoxysilane. Regardless of the comonomer(s) employed, it is generally desired that the primary ethylenically unsaturated monomer(s) constitute at least about 50 mol. %, in some embodiments from about 55 mol. % to about 99 mol. %, and in some embodiments, from about 60 mol. % to about 98 mol. % of the monomers used to form the polymer, while comonomer(s) constitute no more than about 60 mol. %, in some embodiments from about 1 mol. % to about 50 mol. %, and in some embodiments, from about 2 mol. % to about 40 mol. % of the monomers used to form the polymer. To form a network capable of absorbing water, the polymer can be crosslinked during and / or after polymerization. In one embodiment, for instance, the ethylenically unsaturated monomeric compound(s) may be polymerized in the presence of a crosslinking agent to provide a crosslinked polymer. Suitable crosslinking agents typically possess two or more groups that are capable of reacting with the ethylenically unsaturated monomeric compound and that are at least partially water soluble or water dispersible, or at least partially soluble or dispersible in an aqueous monomer mixture. Examples of suitable crosslinking agents may include, for instance, tetraallyloxyethane, N,N'-methylene bisacrylamide, N,N'-methylene bismethacrylamide, triallylamine, trimethylol propane triacrylate, glycerol propoxy triacrylate, divinylbenzene, N-methylol acrylamide, N-methylol methacrylamide, glycidyl methacrylate, polyethylene polyamines, ethyl diamine, ethyl glycol, glycerin, tetraallyloxyethane and triallyl ethers of pentaerythritol, aluminates, silica, alumosilicates, etc., as well as combinations thereof. The amount of the crosslinking agent may vary. In one aspect, the crosslinking agent can be present in an amount of from about 0.005 to about 1.0 mole percent based on moles of the ethylenically unsaturated monomeric compound(s). The superabsorbent polymer particles of the present invention may be prepared by any known polymerization method. For instance, the particles may be prepared by any suitable bulk polymerization technique, such as solution polymerization, inverse suspension polymerization, or emulsion polymerization. In solution polymerization, for instance, the monomer(s) are polymerized in an aqueous solution. In inverse suspension polymerization, the monomers(s) are dispersed in an alicyclic or aliphatic hydrocarbon suspension medium in the presence of a dispersing agent, such as a surfactant or protective colloid. If desired, the polymerization reaction may be conducted in the presence of a free radical initiator, redox initiator (reducing and oxidizing agents), thermal initiator, photoinitiator, etc. Examples of suitable reducing agents may include, for instance, ascorbic acid, alkali metal sulfites, alkali metal bisulfites, ammonium sulfite, ammonium bisulfite, alkali metal hydrogen sulfite, ammonium hydrogen sulfite, ferrous metal salts, e.g., ferrous sulfates, sugars, aldehydes, primary and secondary alcohols, etc. Examples of suitable oxidizing agents may include, for instance, hydrogen peroxide, caprylyl peroxide, benzoyl peroxide, cumene peroxide, tertiary butyl diperphthalate, tertiary butyl perbenzoate, sodium percarbonate, sodium peracetate, alkali metal persulfates, ammonium persulfates, alkylhydroperoxides, peresters, diacryl peroxides, silver salts, etc. Although by no means required, additional components may also be combined with the superabsorbent polymer, before, during, or after polymerization. Additional components, for example, may be used to affect the dynamic vapor sorption properties of the material. In one embodiment, for instance, fillers including fibers can be added. Examples may include carbides (e.g., silicon carbide), silicates (e.g., wollastonite), etc. If desired, a hydrophobic substance may also be combined with the superabsorbent polymer, such as a substance containing a hydrocarbon group, a substance containing a hydrocarbon group having a fluorine atom, a substance having a polysiloxane structure, etc. Hydrophobic substances can also influence the moisture absorption kinetics of the material during short contact times without substantially increasing Vortex times. Examples of such substances as well as superabsorbent particles formed therefrom are described, for instance, in U.S. Pat. No. 8,742,023 to Fujimura, et al., which is incorporated herein in its entirety by reference thereto. For instance, suitable hydrophobic substances may include polyolefin resins, polystyrene resins, waxes, long-chain fatty acid esters, long-chain fatty acids and salts thereof, long-chain aliphatic alcohols, long-chain aliphatic amides, etc., as well as mixtures thereof. In one particular embodiment, a long-chain fatty acid ester may be employed that is an ester of a fatty acid having 8 to 30 carbon atoms and an alcohol having 1 to 12 carbon atoms, such as methyl laurate, ethyl laurate, methyl stearate, ethyl stearate, methyl oleate, ethyl oleate, glycerol monolaurate, glycerol monostearate, glycerol monooleate, pentaerythritol monolaurate, pentaerythritol monostearate, pentaerythritol monooleate, sorbitol monolaurate, sorbitol monostearate, sorbitol monooleate, sucrose monopalmitate, sucrose dipalmitate, sucrose tripalmitate, sucrose monostearate, sucrose distearate, sucrose tristearate, tallow, etc. In another embodiment, a long-chain fatty acid or a salt thereof may be employed that contains 8 to 30 carbon atoms, such as lauric acid, palmitic acid, stearic acid, oleic acid, dimer acid, behenic acid, etc., as well as zinc, calcium, magnesium, and / or aluminum salts thereof, such as calcium palmitate, aluminum palmitate, calcium stearate, magnesium stearate, aluminum stearate, etc. Regardless of the specific manner in which the particles are formed, a variety of different techniques can be employed to initiate the creation of the desired porous network. In certain embodiments, control over the polymerization process itself can lead to the formation of pores within the resulting particles. For instance, polymerization may be conducted in heterogeneous, two phase or multiphase systems, with a monomer-rich continuous phase suspended in a solvent-rich minority phase. As the monomer-rich phase begins to polymerize, pore formation can be induced by the solvent-rich phase. Of course, techniques may also be employed in which a porous network is formed within preformed particles. In one particular embodiment, for instance, a technique known as “phase inversion” may be employed in which a polymer dissolved or swollen in a continuous phase solvent system inverts into a continuous phase solid macromolecular network formed by the polymer. This inversion can be induced through several methods, such as by removal of the solvent via a dry process (e.g., evaporation or sublimation), addition of a non-solvent or addition to a non-solvent via a wet process. In dry processes, for example, the temperature (or the pressure) of the particles can be altered so that the solvent system (e.g., water) can be transformed to another state of matter that can be removed without excessive shrinkage, either by evacuating or purging with a gas. Freeze drying, for instance, involves cooling the solvent system below its freezing point and then allowing it to sublime under reduced pressure so that pores are formed. Supercritical drying, on the other hand, involves heating the solvent system under pressure above the supercritical point so that pores are formed. Wet processes, however, are particularly suitable in that they do not rely on a substantial degree of energy to achieve the desired inversion. In a wet process, the superabsorbent polymer and solvent system may be provided in the form of a single phase homogenous composition. The concentration of the polymer typically ranges from about 0.1% to about 20% wt. / vol., and in some embodiments, from about 0.5% to about 10% wt. / vol. of the composition. The composition is thereafter contacted with a non-solvent system using any known technique, such as by immersing into a bath, countercurrent washing, spray washing, belt spray, and filtering. The difference in chemical potential between the solvent and non-solvent systems causes molecules of the solvent to diffuse out of the superabsorbent polymer, while molecules of the non-solvent diffuse into the polymer. Ultimately, this causes the polymer composition to undergo a transition from a single phase homogeneous composition to an unstable two phase mixture containing polymer-rich and polymer-poor fractions. Micellar droplets of the non-solvent system in the polymer-rich phase also serve as nucleation sites and become coated with polymer, and at a certain point, these droplets precipitate to form a continuous polymer network. The solvent composition inside the polymer matrix also collapses on itself and forms voids. The matrix can then be dried to remove the solvent and non-solvent systems and form stabile porous particles. The exact solvent and non-solvent systems employed to accomplish the phase inversion are not particularly critical, so long they are selected in tandem based on their miscibility. More particularly, the solvent and non-solvent systems can be selected so that they have a specific difference in their Hildebrand solubility parameters, 6, which is a predictive indicator of the miscibility of two liquids with higher values generally representing a more hydrophilic liquid and lower values representing a more hydrophobic liquid. It is generally desired that the difference in the Hildebrand solubility parameter of the solvent system and the non-solvent system (e.g., 6solvent6non-solvent) is from about 1 to about 15 calories 1 / 2 / cm3 / 2, in some embodiments from about 4 to about 12 calories1 / 2 / cm3 / 2, and in some embodiments, from about 6 to about 10 calories1 / 2 / cm3 / 2. Within these ranges, the solvent / non-solvent will have enough miscibility to allow solvent extraction to occur, but not too miscible so that phase inversion could not be accomplished. Suitable solvents for use in the solvent system may include, for instance, water, saline, glycerol, etc., as well as combinations thereof. Likewise, suitable non-solvents for use in the non-solvent system may include acetone, n-propyl alcohol, ethyl alcohol, methanol, n-butyl alcohol, propylene glycol, ethylene glycol, etc., as well as combinations thereof. Typically, the volume ratio of the solvent system to the non-solvent system ranges from about 50:1 to about 1:200 (volume per volume), in some embodiments from about 10:1 to about 1:180 (volume per volume), in some embodiments from about 1:1 to about 1:160 (volume per volume), in some embodiments from about 1:60 to about 1:150 (volume per volume), in some embodiments from about 1:1 to about 1:60 (volume per volume), and in some embodiments from about 1:1 to about 1:2 (volume per volume). After contact with the non-solvent and the phase inversion is completed, the liquid phase may be dried and / or removed using any suitable technique, such as by increased temperature, time, vacuum, and / or flow rate control using any suitable equipment (e.g., forced air ovens and vacuum ovens). In one example, for instance, high temperature drying at temperatures up to about 175° C. can leave up to about 16% wt. ethanol in the sample. The sample can then be placed in a humidity chamber at 69° C. at a 50% relative humidity to reduce the ethanol content to less than 0.13%. If desired, the size of the superabsorbent particles may be manipulated or controlled in order to affect the moisture absorption properties of the material. Particle size and morphology can be controlled through process conditions or through post production processes. For instance, the particle can be ground to a desired particle size distribution. One particularly suitable downsizing apparatus, for instance, is available commercially from Pallmann Industries (Clifton, N.J.) under the name Turbofiner®, type PLM. In this apparatus, a high activity air whirl is created within a cylindrical grinding chamber between a stationary grinding element and a rotating grinding element of an impact grinding mill. Due to the high air volume, the particles can be impacted into a desired particle size. Yet another suitable particle formation technique is known as cryogenic disk milling. Cryogenic disk milling generally employs a liquid (e.g., liquid nitrogen) to cool or freeze the material prior to and / or during grinding. In one embodiment, a single-runner disk milling apparatus can be employed that has a stationary disk and a rotating disk. The material enters between the discs via a channel near the disk center and is formed into particles through the frictional forces created between the discs. One suitable cryogenic disk milling apparatus is available under the name Wedco® cryogenic grinding system from ICO Polymers (Allentown, Pa.). In one aspect, the superabsorbent particle incorporated into absorbent structures made in accordance with the present disclosure can have a relatively large particle size for decreasing moisture absorption during short contact times without significantly affecting vortex times. For instance, the average particle size of the superabsorbent particles can be from about 100 microns to about 1,500 microns, including all increments of one micron therebetween. For instance, the superabsorbent particles can have an average particle size of greater than about 150 microns, such as greater than about 200 microns, such as greater than about 250 microns, such as greater than about 300 microns, such as greater than about 350 microns, such as greater than about 400 microns, and less than about 1,000 microns, such as less than about 900 microns, such as less than about 800 microns, such as less than about 700 microns, such as less than about 600 microns. In one aspect, average particle size can be determined using a sieve method per ISO Test 17190-3. A suitable sieve device, for instance, is a Retsch AS 200 vibratory sieve shaker. As shown above, various techniques and controls can be used in order to change the water absorption properties of the superabsorbent materials. For example, the short contact time moisture kinetics and the swell time kinetics of the superabsorbent materials can be controlled and influenced through the monomers used to form the superabsorbent particles, by incorporating various additives into the superabsorbent particles including hydrophobic additives, by controlling the pore size of the superabsorbent particles, and / or by controlling the particle size of the superabsorbent particles. In accordance with the present disclosure, the superabsorbent particles are formulated or otherwise selected such that the superabsorbent material displays a dynamic vapor sorption of less than about 3% after 7 minutes when placed in an environment at 95% relative humidity and at a temperature of 35°C. For instance, the superabsorbent material can display a dynamic vapor sorption of less than about 2.75%, such as less than about 2.5%, such as less than about 2.25%, such as less than about 2%. The dynamic vapor sorption of the superabsorbent material is generally greater than about 0.25%, such as greater than about 0.5%, such as greater than about 0.75%, such as greater than about 1%. The superabsorbent material is also selected so as to have a vortex time of less than about 55 seconds, such as less than about 53 seconds, such as less than about 51 seconds. In one aspect, the vortex time can be less than about 48 seconds, such as less than about 45 seconds, such as less than about 43 seconds, such as less than about 40 seconds. The vortex time is generally greater than about 10 seconds. Superabsorbent materials for use in the process of the present disclosure can also possess a relatively low surface energy. Surface energy, for instance, can be measured with Inverse Gas Chromatography (e.g., IGC). IGC can be conducted, for instance, using a gas chromatograph from the Hewlett Packard™ series. In one aspect, superabsorbent materials for use in the present disclosure possess a bulk surface energy of less than about 53 mJ / m2, such as less than about 51 mJ / m2, such as less than about 47 mJ / m2, such as less than about 45 mJ / m2, such as less than about 43 mJ / m2. The bulk surface energy can be greater than about 20 mJ / m2, such as greater than about 28 mJ / m2 As described above, in addition to selecting a superabsorbent material with desired moisture absorption characteristics, the superabsorbent material is fed into a process in which the superabsorbent material is contacted with free water for a time of generally less than about 5 seconds prior to being drained of fluids. For example, referring to FIGS. 1-3, three different process schematics are shown that may be used to produce absorbent structures in accordance with the present disclosure. The process schematics illustrated in FIGS. 1-3, however, are for exemplary purposes only. Like reference numerals have been used in all of the figures for ease of explanation and indicate similar elements. Referring to FIG. 1, one exemplary process 11, particularly a foam forming process for making nonwoven materials containing superabsorbent particles is illustrated. The process 11 of FIG. 1 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. Optionally, 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. The fibers contained in the first fluid supply 16, for instance, can comprise cellulose fibers, such as cellulose pulp fibers, alone or in combination with synthetic polymer fibers. 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 surfactant provided by a supply of 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 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 which 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 a desirable absorbent nonwoven material 10 including, for example, strength and the visual appearance of quality. 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 in certain embodiments the ratio of air:other 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. 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 mixer 24, 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 is provided having therein one or more rotors or impellors 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 mixer 24. 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. 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. 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 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 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. The foam density of the foam forming the first fluid supply 16 in the first tank 14 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. In one aspect, the fluid supply 16 can be at a relatively low temperature in order to prevent or inhibit the fluid supply 16 from being absorbed by the superabsorbent material when combined together. For instance, the fluid supply 16 can be at a temperature of less than about 20°C, such as less than about 18°C, such as less than about 15°C, and greater than about5°C. The system can also include a first pump 36. 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. In some embodiments, the first pump 36 can be a progressive cavity pump or a centrifugal pump, however, it is contemplated that other suitable types of pumps can be used. As depicted in FIG. 1, the process 11 can also include a component feed system 40. The component feed system 40 can be used to deliver a supply of component 44 containing a superabsorbent material, in this embodiment, directly to a 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 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 refilling the supply of the component 44 to the component supply area 42. 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 Christy Machine & Conveyor, Fremont, Ohio. The component feed system 40 can also be configured as a conveyor system in some embodiments. 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. The supply of the component 44 can be in the form of a particulate and / or a fiber and / or a powder. As described herein, the supply of the component 44 can be superabsorbent material (SAM) in particulate form and having desired absorbency characteristics. The component feed system 40 as described herein is 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. The pressure control system 50 can be used to better control the flow of the superabsorbent material 44 and to assist in combining the component 44 containing the superabsorbent material with the fluid supply 16. In some embodiments, it may be beneficial to 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 can be reduced or eliminated. 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 process 11. It is also contemplated that other additional aspects of a pressure control system 50 can 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. As shown in FIG. 1, the component feed system 40 supplies the component 44 directly to the head box 80. In the head box 80, the component 44 is combined with the first fluid supply 16 or foam and mixed together to form a slurry 76. The slurry 76 exits the head box 80 and is deposited onto a forming surface 94 and dewatered by a dewatering device 96 for producing a nonwoven web 10. The forming surface 94 can be a foraminous sheet, such as a woven belt or screen, or any other suitable surface for accepting the slurry 76. The dewatering system 96 is configured to remove liquid from the resultant slurry 76 on the forming surface 94. The dewatering system 96, for instance, can be configured to apply a suction force to the slurry 76 for draining fluid from the newly formed nonwoven web 10. In one aspect, the dewatering system 96 can begin dewatering the slurry 76 while still within the head box 80. The process 11 can further include a drying system 98 that is designed to dry the nonwoven web 10 containing the superabsorbent material. The drying system 98 can apply heat to the nonwoven web 10, such as by providing heated air in a through-air drying system. As the nonwoven web 10 is formed, the web 10 can then be wound into a roll for later being fed into a process for making absorbent articles. In this regard, the process 11 can include a winding system 99 that is configured to spirally wind the nonwoven web 10. In the embodiment illustrated in FIG. 1, as described above, the superabsorbent material can remain in a dry state until the material enters the head box 80 and is combined with the fluid supply or foam 16. In this manner, the amount of time the superabsorbent material is contacted with free moisture is relatively short. For instance, the superabsorbent material, during the process, can be in contact with the aqueous fluid or foam for less than about 5 seconds prior to being transferred to the forming surface and dewatered. More particularly, the process 11 can be configured such that the superabsorbent material contacts free water for less than about 4 seconds, such as less than about 3 seconds, such as less than about 2 seconds, prior to being dewatered and / or placed on the forming surface. In this manner, the amount of moisture absorbed by the superabsorbent material is minimized. By also selecting a superabsorbent material that displays a relatively low dynamic vapor sorption, the amount of energy needed to dry the nonwoven web 10 can be minimized for producing the nonwoven web at dramatically lower energy requirements. In addition, the process 11 can run at faster speeds for further improving efficiency. Referring to FIG. 2, another embodiment of a process 11 that may be used to form nonwoven webs containing an absorbent material in accordance with the present disclosure is shown. Like reference numerals have been used to indicate similar elements. Similar to FIG. 1, the process 11 illustrated in FIG. 2 includes a fluid supply 16 that is formed within a tank 14 from a fluid provided by a supply of fluid 18, from a surfactant provided by a supply of surfactant 22, and optionally from a plurality of fibers provided by a supply of fibers 20. The tank 14 can include a mixer 24 designed to produce a foam that is then pumped to a head box 80 by a pump 36. The process 11 further includes a component feed system 40 that is used to deliver a supply of component 44 to the process. The component 44 contains a superabsorbent material selected in accordance with the present disclosure. The component 44 can be fed to a component supply area 42 through a hopper 48. The component feed system 40 can further include a pressure control system 50. The pressure control system 50 can include a housing 52 that forms a pressurized seal volume around the component feed system 40. The pressure control system 50 can also include a bleed orifice 54. In the embodiment illustrated in FIG. 2, the component 44 containing the superabsorbent particles is fed through an outlet conduit 46 and, instead of being fed directly to a head box 80, is fed to a mixing junction 56, which can be an eductor (also commonly referred to as a jet pump). The mixing junction 56 is in fluid communication with the outlet conduit 46 of the component feed system 40 and is also in fluid communication with the fluid supply 16 which can be in the form of a foam. As shown, the 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 fluid supply 16. The mixing junction 56 can also include a discharge 64 that leads into the head box 80. The mixing junction 56 is designed to very rapidly mix the dry component 44 with the fluid supply 16 or foam. For instance, when configured as an eductor, the mixing junction 56 can rapidly mix the supply of the component 44 from the component feed system 40 with the fluid supply 16. In one aspect, the fluid supply 16 can provide 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 fluid supply 16. The motive pressure can create a vacuum on the supply of the component 44 of less than about 1.5 in Hg. Alternatively, the motive pressure can create a vacuum on the supply of the component 44 of 5 in Hg or more, such as at least about 10 in Hg or more, and generally less than about 300 in Hg. The mixing junction 56 can be used to ensure robust mixing between the dry component 44 containing the superabsorbent material and the foam from the fluid supply 16. The mixing junction 56 can also be located directly adjacent to the head box 80 for feeding a resultant slurry 76 to the head box. The slurry 76 is then deposited onto a forming surface 94 and dewatered using a dewatering system 96. The slurry 76 is formed into a nonwoven substrate 10 and dried using a drying system 98 prior to being wound into a roll by a winding system 99. Of particular advantage, the mixing junction 56 and head box 80 are configured such that the dry superabsorbent material is in contact with free moisture for a time of less than about 5 seconds, such as less than about 4 seconds, such as less than about 3 seconds, such as even less than about 2 seconds. The process illustrated in FIG. 2 not only allows for rapid mixing of the superabsorbent material with the foam but also rapidly transfers the foam to the forming surface 94 for dewatering. Still another embodiment of a process in accordance with the present disclosure for producing nonwoven webs containing a superabsorbent material is illustrated in FIG. 3. In the embodiment illustrated in FIG. 3, the dry superabsorbent material is combined with a foam supply in a mixing junction or eductor and then fed to a head box and mixed with greater amounts of a foam for forming a slurry that is then deposited onto a forming surface. For instance, referring to FIG. 3, the process 11 includes a first fluid supply 16 that is formed within a first tank 14 that is equipped with a mixer 24. A supply of a liquid 18, a supply of a surfactant 22, and optionally a supply of fibers 20 can be fed to the tank 24 for forming a foam. Once formed, the first fluid supply 16 or foam is then pumped to a head box 80 through the use of a first pump 36. As shown in FIG. 3, the process 11 includes a second fluid supply 28. The fluid supply 28 is formed within a second tank 26 that includes a second mixer 34. The fluid supply 28 is formed from mixing a fluid from a supply of fluid 30 with a surfactant from a supply of surfactant 32. The fluid supply 28 is pumped using a second pump 38 into a mixing junction 56, which can comprise an eductor. The process 11 further includes a component feed system 40 similar to the component feed systems illustrated in FIGS. 1 and 2. The component feed system 40 includes a component supply area 42 that contains a supply of component 44 containing a superabsorbent material selected in accordance with the present disclosure. The component feed system 40 can also include a hopper 48 for receiving further amounts of the component 44. The component feed system 40 can also include a pressure control system 50 that includes a housing 52 and optionally a bleed orifice 54. An outlet conduit 46 feeds the component 44 containing the superabsorbent material into the mixing junction 56, which can comprise an eductor. As shown, the mixing junction 56 can include a first inlet 60 for receiving the superabsorbent material, a second inlet 62 for receiving the fluid supply 28, and a discharge 64 for feeding a foam suspension of superabsorbent particles into the head box 80. Within the head box 80, the mixture of the second fluid supply 28 and the component 44 are combined with the first fluid supply 16 for forming a slurry 76 that is then deposited onto a forming surface 94 and dewatered using the dewatering system 96. A nonwoven web 10 is formed that is dried by the drying system 98 and wound into a roll by a winding system 99. In the embodiment illustrated in FIG. 3, the superabsorbent material in a dry state can be combined with the second fluid supply 28, fed to the head box 80, combined with the first fluid supply 16 and deposited onto the forming surface and / or dewatered at a relatively fast pace or flow rate. The superabsorbent material, for instance, can be in contact with free moisture prior to being deposited on the forming surface and / or dewatered for a time of less than about 5 seconds, such as less than about 4 seconds, such as less than about 3 seconds, such as even less than about 2 seconds, similar to the process configurations illustrated in FIGS. 1 and 2. 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. The foam forming processes as described herein can utilize one or more surfactants. The fibers and 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 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 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 surfactant can be used, including different types of surfactants, as long as they are compatible, and more than one surfactant of the same type. For example, a combination of a cationic surfactant and a nonionic surfactant or a combination of an anionic surfactant and a nonionic surfactant may be used in some embodiments due to their compatibilities. However, in some embodiments, a combination of a cationic surfactant and an anionic surfactant may not be satisfactory to combine due to incompatibilities between the surfactants. Anionic 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 surfactants believed suitable for use in the present disclosure include alkali metal sulfoncmates, 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 pal mi tonitri Ie 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 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 surfactant is sodium dodecyl sulfate (SDS). Cationic 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 surfactants may be less preferable to use due to potential interaction between the cationic 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 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 trimethyl 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-hydroxylethylstearylamide, and amine salts of long chain fatty acids. Further examples of cationic surfactants believed suitable for use with the present disclosure include benzalkonium chloride, benzethonium chloride, cetrimonium bromide, distearyldimethylammomum chloride, tetramethylammonium hydroxide, and so forth. Nonionic 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 non-ionic 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. 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). In some embodiments, 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. 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). Nonwoven webs made according to the present disclosure contain the superabsorbent particles having the desired water absorption characteristics. The nonwoven web can contain the superabsorbent material in an amount from about 10% by weight to about 100% by weight, including all increments of 1% by weight therebetween. For instance, the nonwoven web formed in accordance with the present disclosure can contain the superabsorbent material in an amount greater than about 15% by weight, such as in an amount greater than about 30% by weight, such as in an amount greater than about 50% 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, such as in an amount greater than about 90% by weight, such as in an amount greater than about 95% by weight. In one aspect, the nonwoven web contains the superabsorbent particles combined with fibers, such as cellulose fibers and / or polymer synthetic fibers. When combined with fibers, the nonwoven web can contain the superabsorbent particles in an amount less than about 90% by weight, such as in an amount less than about 80% by weight, such as in an amount less than about 70% by weight. The nonwoven web made in accordance with the present disclosure can have a basis weight of from about 100 gsm to about 1,500 gsm, including all increments of 1 gsm therebetween. For instance, the basis weight of the nonwoven web can be greater than about 50 gsm, such as greater than about 150 gsm, such as greater than about 200 gsm, such as greater than about 250 gsm, such as greater than about 300 gsm, such as greater than about 350 gsm, and less than about 1,000 gsm, such as less than about 800 gsm, such as less than about 600 gsm. The nonwoven web can have not only very good water absorption properties but can also have excellent strength. For instance, the nonwoven web can have a tensile strength in at least one direction of greater than about 700 gf / in, such as greater than about 1,000 gf / in, such as greater than about 1,200 gf / in, such as greater than about 1,400 gf / in, such as greater than about 1,500 gf / in, and less than about 15,000 gf / in. Tensile strength can be measured in accordance with ASTM Test D-5034. In one aspect, the nonwoven web contains the superabsorbent material combined with cellulose fibers. The cellulose fibers, for instance, can comprise cellulose pulp fibers and / or synthetic cellulose fibers, such as regenerated cellulose fibers. Various different types of cellulose fibers can be incorporated into the nonwoven web. In some embodiments, the fibers utilized can be conventional papermaking fibers such as wood pulp fibers formed by a variety of pulping processes, such as kraft pulp, sulfite pulp, bleached chemithermomechanical pulp (BCTMP), chemithermomechanical pulp (CTMP), pressure / pressure thermomechanical pulp (PTMP), thermomechanical pulp (TMP), thermomechanical chemical pulp (TMCP), and so forth. By way of example only, fibers and methods of making wood pulp fibers are disclosed in US4793898 to Laamanen et al.; US4594130 to Chang et al.; US3585104 to Kleinhart; US5595628 to Gordon et al.; US5522967 to Shet; and so forth. Further, the fibers may be any high-average fiber length wood pulp, low-average fiber length wood pulp, or mixtures of the same. Examples of suitable high-average length pulp fibers include softwood fibers, such as, but not limited to, northern softwood, southern softwood, redwood, red cedar, hemlock, pine (e.g., southern pines), spruce (e.g., black spruce), and the like. Examples of suitable low-average length pulp fibers include hardwood fibers, such as, but not limited to, eucalyptus, maple, birch, aspen, and the like. Moreover, if desired, secondary fibers obtained from recycled materials may be used, such as fiber pulp from sources such as, for example, newsprint, reclaimed paperboard, and office waste. In some embodiments, refined fibers can be such that the total amount of virgin and / or high average fiber length wood fibers, such as softwood fibers, may be reduced. Regardless of the origin of the wood pulp fiber, the wood pulp fibers preferably have an average fiber length greater than about 0.2 mm and less than about 3 mm, such as from about 0.35 mm and about 2.5 mm, or between about 0.5 mm to about 2.5 mm or even between about 0.7 mm and about 2.0 mm. In addition, other cellulosic fibers that can be used in the present disclosure includes nonwoody fibers. As used herein, the term “non-wood fiber” generally refers to cellulosic fibers derived from non-woody monocotyledonous or dicotyledonous plant stems. Non-limiting examples of dicotyledonous plants that may be used to yield non-wood fiber include kenaf, jute, flax, ramie and hemp. Non-limiting examples of monocotyledonous plants that may be used to yield non-wood fiber include cereal straws (wheat, rye, barley, oat, etc.), stalks (corn, cotton, sorghum, Hesperaloe funifera, etc.), canes (bamboo, sisal, bagasse, etc.) and grasses (miscanthus, esparto, lemon, sabai, switchgrass, etc). In still other certain instances non-wood fiber may be derived from aquatic plants such as water hyacinth, microalgae such as Spirulina, and macroalgae seaweeds such as red or brown algae. Still further, other cellulosic fibers for making substrates herein can include synthetic cellulose fiber types formed by spinning, including rayon in all its varieties, and other fibers derived from viscose or chemically-modified cellulose such as, for example, those available under the trade names LYOCELL and TENCEL. Crosslinked cellulosic fibers can also be used in forming nonwoven materials described herein. Crosslinked cellulosic fibers can provide increased bulk and resiliency, as well as improved softness. In some embodiments, non-woody and / or synthetic cellulosic fibers can be combined with the superabsorbent material. The fibers can have a 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 15 mm. Generally speaking, when fibers of relatively larger average length are being used, it may often be advantageous to modify the amount and type of foaming surfactant. For example, in some embodiments, if fibers of relatively larger average length are being used, it may be beneficial to utilize relatively higher amounts of foaming surfactant in order to help achieve a foam with the required foam half life. When forming single layer nonwoven webs or absorbent structures, the nonwoven web can contain cellulose fibers generally in an amount greater than about 5% 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 90% by weight, such as in an amount less than about 70% by weight, such as in an amount less than about 50% by weight, such as in an amount less than about 40% by weight. Nonwoven webs made in accordance with the present disclosure can also contain synthetic polymer fibers including binder fibers that are combined with the superabsorbent material. In one aspect, the nonwoven web can contain the superabsorbent material, cellulose fibers as described above, and polymer synthetic fibers. 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 marine 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. 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. 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. Polymer synthetic fibers and / or binder fibers can be present in the nonwoven web in an amount greater than about 3% by weight, such as in an amount greater than about 5% by weight, such as 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 12% by weight, such as in an amount greater than about 15% by weight, and 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, such as in an amount less than about 20% by weight. Nonwoven webs made according to the present disclosure can comprise single layer webs or can comprise multi-layer webs. When forming multi-layer webs, an absorbent layer containing the superabsorbent material can be combined with one or more other layers that contain minimal amounts of the superabsorbent material, such as in amounts less than about 5% by weight. In one aspect, the nonwoven web made according to the present disclosure can be a three-layer web that includes a first layer, a second layer, and a third layer. The superabsorbent material can be contained primarily in the second layer and can be positioned between the first layer and the third layer. The first layer, for instance, can be a top layer that is configured to face a wearer when the nonwoven web is incorporated into an absorbent article. The first layer, for instance, can be designed as an intake layer that quickly allows fluids to be absorbed by the second layer containing the superabsorbent material. Thus, the first layer can be a low density layer with high permeability characteristics. The top layer, for instance, can contain binder fibers in an amount from about 10% by weight to about 100% by weight, such as from about 20% by weight to about 80% by weight. The first layer or top layer can also contain synthetic polymer fibers generally in an amount from about 1% by weight to about 80% by weight, such as from about 5% by weight to about 60% by weight. The first layer or top layer can also contain cellulose fibers in an amount from about 1% by weight to about 80% by weight, such as from about 5% by weight to about 35% by weight. The top layer or first layer can have a basis weight of from about 10 gsm to about 100 gsm, such as from about 15 gsm to about 50 gsm. The third layer or bottom layer can serve as a containment layer for maintaining the superabsorbent material within the middle layer of the absorbent structure. The third layer can contain binder fibers alone or in combination with cellulose fibers and / or polymer synthetic fibers. The binder fibers can be present in the third layer in an amount from about 20% to about 100% by weight, such as from about 20% to about 50% by weight. Cellulose fibers, such as pulp fibers, can be present in the third layer or bottom layer in an amount from about 10% by weight to about 90% by weight, such as from about 10% by weight to about 60% by weight. Optionally, the third layer or bottom layer can contain polymer synthetic fibers in an amount from about 3% by weight to about 20% by weight. The third layer or bottom layer can be constructed to be relatively liquid impermeable or, alternatively, can be constructed to be liquid permeable depending upon the application. The third layer can have a basis weight of from about 5 gsm to about 40 gsm, such as from about 10 gsm to about 25 gsm. The middle layer or second layer containing the superabsorbent material can be constructed as described above with respect to single layer nonwoven webs. For instance, the second layer can be made exclusively from a superabsorbent material, can contain a superabsorbent material in combination with cellulose fibers, can contain a superabsorbent material in combination with polymer synthetic fibers, or can contain a superabsorbent material in combination with cellulose fibers and polymer synthetic fibers. Nonwoven materials made in accordance with the present disclosure can also contain various other components and additives. For instance, the nonwoven material can contain strength additives. 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. 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. When a wet or dry strength additive is used, it is preferable to select such an additive to be 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. If used, such wet and dry 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. 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, 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. Nonwoven webs made according to the present disclosure containing the superabsorbent material are particularly well suited for use as absorbent structures in personal care products. The nonwoven webs are also well suited for producing various other products, such as wipes and wipers. As shown in FIGS. 1-3, in one embodiment, the nonwoven web is wound into a roll. When incorporated into a personal care product, the roll of material can be unwound and cut into individual absorbent structures that can then be incorporated into absorbent articles. The absorbent article, for instance, can be a diaper, a diaper insert, a child training pant, or other child absorbent pant. The absorbent article can also be an adult incontinence product, a feminine hygiene product, or a bedmat. The absorbent article can include a fluid permeable liner and an outer cover. The absorbent structure of the present disclosure can form an absorbent core positioned between the fluid permeable liner and the outer cover. In one embodiment, a surge layer can be placed in between the absorbent core and the fluid permeable liner for directing and channeling fluids into the absorbent core in a fast and efficient manner. The present disclosure may be better understood with reference to the following examples. Examples As described above, superabsorbent materials for use in constructing nonwoven webs in accordance with the present disclosure are selected to have particular water absorbency characteristics. Ideally, the superabsorbent material has relatively low water absorption kinetics over short contact times. Over longer contact times, however, ideally the superabsorbent material has higher kinetics in that the superabsorbent particles reach a maximum swelling point very rapidly. For instance, in one aspect, superabsorbent materials selected for use in the present disclosure display a dynamic vapor sorption of less than about 3% after 7 minutes when placed in an environment at 95% relative humidity and at a temperature of 35°C and also display a vortex time of less than about 55 seconds. As described above, various controls are available for controlling the above properties, which appear to be somewhat unrelated. For instance, superabsorbent materials can be made in accordance with the present disclosure by changing the chemical makeup of the material using different monomers in different proportional amounts. In addition, the water absorption properties of the superabsorbent material can be changed and controlled by adding various different additives, such as high aspect ratio components, hydrophobic components, and the like. Other factors that may affect the water absorption properties of the superabsorbent material include controlling the pore size of the superabsorbent particles and / or controlling the average particle size and the particle size distribution of the superabsorbent material. In the following experiment, various different commercially available superabsorbent materials were tested for dynamic vapor sorption (“DVS”) and compared to the vortex time of each material as provided by the manufacturer. The following results were obtained: Sample No. DVS - SAM mass % change at 7min DVS- SAM mass % change at 10min DVS- SAM mass % change at 13min Vortex time (sec) 1 1.2 2.3 3.4 50 2 1.9 3.7 5.6 35 3 2.3 4.1 6 50 4 3.4 5.6 7.8 52 5 4 6.8 9.7 39 6 2.0 3.6 5.3 50 7 3.6 6.1 8.5 65 As shown above, Sample Nos. 1,2, 3 and 6 have water absorbency characteristics that make the superabsorbent materials well suited for use in the process of the present disclosure. 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, 5 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

What Is Claimed:

1. A process for forming an absorbent structure, the process comprising: combining a superabsorbent material with a fluid supply, the fluid supply comprising an aqueous fluid optionally containing fibers, the superabsorbent material being mixed with the fluid supply to form a slurry;5            transferring the resultant slurry to a forming surface;draining fluids from the resultant slurry to form a nonwoven web containing the superabsorbent material, and wherein, prior to being transferred to the forming surface, the superabsorbent material is in contact with the aqueous fluid for less than about 5 seconds, the superabsorbent material displaying a dynamic vapor sorption of less than about 3% after 7 minutes10 when placed in an environment at 95% relative humidity and at a temperature of 35° C, the superabsorbent material displaying a vortex time of less than about 55 seconds.

2. A process as defined in claim 1, wherein the process further includes the step of drying the nonwoven web.

3. A process as defined in any of the preceding claims, wherein the aqueous fluid comprises a foamed suspension of fibers.

4. A process as defined in any of the preceding claims, wherein the aqueous fluid comprises fibers, water, and a surfactant.

5. A process as defined in any of the preceding claims, wherein the superabsorbent material is combined with the fluid supply adjacent to a headbox that receives the slurry and transfers the slurry to the forming surface.

6. A process as defined in any of the preceding claims, wherein the superabsorbent material, prior to being transferred to the forming surface, is in contact with the aqueous fluid for less than about 4 seconds, such as less than about 3 seconds, such as less than about 2 seconds prior to draining fluids.

7. A process as defined in any of the preceding claims, wherein the superabsorbent material is fed to the process in a dry state and contacts free water during the process for less than about 5 seconds, such as less than about 4 seconds, such as less than about 3 seconds, such as less than about 2 seconds prior to draining fluids.

8. A process as defined in any of the preceding claims, wherein the superabsorbent material displays a dynamic vapor sorption of less than about 2.8%, such as less than about 2.5%, such as less than about 2.3%, such as less than about 2% after 7 minutes when placed in an environment at 95% relative humidity and at a temperature of 35°C.

9. A process as defined in any of the preceding claims, wherein the process further includes the step of feeding the nonwoven web into a through-air dryer.

10. A process as defined in any of the preceding claims, wherein the slurry is drained of fluids by a combination of gravity and by applying a suction force to the slurry.

11. A process as defined in any of the preceding claims, wherein the aqueous fluid is at a temperature when combined with the superabsorbent material of less than about 20°C, such as less than about 18°C, such as less than about 15°C.

12. A process as defined in any of the preceding claims, wherein the superabsorbent material comprises particles, the particles have an average particle size of greater than about 300 microns, such as greater than about 350 microns, such as greater than about 400 microns, such as greater than about 450 microns, such as greater than about 500 microns, such as greater than about 550 microns, such as greater than about 600 microns, and less than about 1,500 microns.

13. A process as defined in any of the preceding claims, wherein the nonwoven web comprises a single layer web.

14. A process as defined in any of claims 1 through 12, wherein the resultant slurry is transferred to the forming surface with at least one other fibrous layer, the nonwoven web comprising a multi-layered web.

15. A process as defined in claim 14, wherein the multi-layered web includes a first layer, a second layer, and a third layer, the superabsorbent material being contained in the second layer positioned between the first layer and the second layer.

16. A process as defined in any of the preceding claims, wherein the nonwoven web has a tensile strength in at least one direction of greater than about 700 gf / in, such as greater than about 1,000 gf / in, such as greater than about 1,200 gf / in, such as greater than about 1,400 gf / in, such as greater than about 1,500 gf / in.

17. A process as defined in any of the preceding claims, wherein the nonwoven web has a basis weight of greater than about 50 gsm, such as greater than about 150 gsm, such as greater than about 200 gsm, such as greater than about 250 gsm, such as greater than about 300 gsm, such as greater than about 350 gsm, and less than about 800 gsm, such as less than about 600 gsm.

18. A process as defined in any of the preceding claims, wherein the nonwoven web contains the superabsorbent material in an amount greater than about 10% by weight, such as in an amount greater than about 30% by weight, such as in an amount greater than about 50% by weight, such as in an amount greater than about 60% by weight, such as in an amount greater than about5   70% by weight, such as in an amount greater than about 80% by weight, such as in an amount greaterthan about 90% by weight, such as in an amount greater than about 95% by weight.

19. A process as defined in any of the preceding claims, wherein the nonwoven web contains pulp fibers, synthetic polymer fibers, or mixtures thereof combined with the superabsorbent material.

20. A process as defined in any of the preceding claims, further comprising the step of cutting the nonwoven material into individual absorbent structures.

21. A process as defined in claim 20, further comprising the step of incorporating the individual absorbent structures into absorbent articles.

22. An absorbent structure made according to the process as defined in any of the preceding claims.

23. An absorbent article containing the absorbent structure as defined in claim 22.

24. An absorbent article as defined in claim 23 comprising:a fluid permeable liner;an outer cover; andthe absorbent structure positioned between the liner and the outer cover.

25. An absorbent article as defined in claim 23 or 24, wherein the absorbent article comprises a diaper, a diaper insert, or a child pant.

26. An absorbent article as defined in claim 23 or 24, wherein the absorbent article comprises an adult incontinence product or a feminine hygiene product.

27. An absorbent article as defined in claim 23 or 24, wherein the absorbent article comprises a bedmat.

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