Low bleed airlaid nonwoven material

Abstract

There is a constant demand and a continuing need to provide nonwoven materials with low run-off properties in order to reduce or prevent undesired leakage while exhibiting the desired properties of acquisition, distribution and storage of liquids. The presently disclosed subject matter addresses these and other needs.SOLUTION: Nonwoven materials that provide low runoff and methods of making the same are provided. Such a nonwoven material may be absorbent and comprises a three dimensional pattern on one or more of its surfaces. Such materials may be airlaid and may include multiple layers comprised of cellulosic and synthetic fibers. The nonwoven material may have a percent runoff of less than about 5%.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority to U.S. Provisional Patent Application No. 62 / 854,546, filed May 30, 2019, the contents of which are incorporated herein by reference in their entirety.

[0002] The subject matter of the present disclosure relates to nonwoven materials and methods of making the same. Such nonwoven materials can be absorbent and advantageously provide low runoff. Among other things, such structures include a three-dimensional pattern on one or more surfaces thereof. [Background technology]

[0003] Nonwoven structures are important in a wide range of consumer products, such as absorbent articles, including baby diapers, adult incontinence products, sanitary napkins, and the like. In some nonwoven articles, there is often an absorbent core to receive and retain body fluids. The absorbent core is typically disposed between a liquid-permeable topsheet, whose function is to allow fluid to pass through to the core, and a liquid-impermeable backsheet, whose function is to contain fluid and prevent it from passing through the absorbent article and reaching the clothing of the wearer of the absorbent article. In some nonwoven articles, an acquisition-distribution layer (ADL) can be used in combination with the absorbent core.

[0004] Such nonwoven structures have runoff, which describes the tendency of fluids, such as menses or urine, to overflow the surface of the absorbent material before the fluid can be adequately collected by the absorbent, which can result in undesirable leakage from finished absorbent products, such as feminine sanitary napkins, panty liners, and adult incontinence devices. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Patent No. 5,492,759 [Patent Document 2] U.S. Patent No. 5,601,921 [Patent Document 3] U.S. Patent No. 6,159,335 [Patent Document 4] U.S. Patent No. 4,432,833 [Patent Document 5] U.S. Patent No. 4,425,186 [Patent Document 6] U.S. Patent No. 5,776,308 [Patent Document 7] U.S. Patent No. 4,098,996 [Patent Document 8] U.S. Patent No. 5,547,541 [Patent Document 9] U.S. Patent No. 4,731,269 [Patent Document 10] U.S. Patent No. 5,372,885 [Patent Document 11] U.S. Patent No. 5,456,982 [Patent Document 12] U.S. Patent No. 4,950,541 [Patent Document 13] U.S. Patent No. 5,082,899 [Patent Document 14] U.S. Patent No. 5,126,199 [Patent Document 15] U.S. Patent No. 5,705,565 [Patent Document 16] U.S. Patent No. 2,861,319 [Patent Document 17] U.S. Patent No. 2,931,091 [Patent Document 18] U.S. Patent No. 2,989,798 [Patent Document 19] U.S. Patent No. 3,038,235 [Patent Document 20] U.S. Patent No. 3,081,490 [Patent Document 21] U.S. Patent No. 3,117,362 [Patent Document 22] U.S. Patent No. 3,121,254 [Patent Document 23] U.S. Patent No. 3,188,689 [Patent Document 24] U.S. Patent No. 3,237,245 [Patent Document 25] U.S. Patent No. 3,249,669 [Patent Document 26] U.S. Patent No. 3,457,342 [Patent Document 27] U.S. Patent No. 3,466,703 [Patent Document 28] U.S. Patent No. 3,469,279 [Patent Document 29] U.S. Patent No. 3,500,498 [Patent Document 30] U.S. Patent No. 3,585,685 [Patent Document 31] U.S. Patent No. 3,163,170 [Patent Document 32] U.S. Patent No. 3,692,423 [Patent Document 33] U.S. Patent No. 3,716,317 [Patent Document 34] U.S. Patent No. 3,778,208 [Patent Document 35] U.S. Patent No. 3,787,162 [Patent Document 36] U.S. Patent No. 3,814,561 [Patent Document 37] U.S. Patent No. 3,963,406 [Patent Document 38] U.S. Patent No. 3,992,499 [Patent Document 39] U.S. Patent No. 4,052,146 [Patent Document 40] U.S. Patent No. 4,251,200 [Patent Document 41] U.S. Patent No. 4,350,006 [Patent Document 42] U.S. Patent No. 4,370,114 [Patent Document 43] U.S. Patent No. 4,406,850 [Patent Document 44] U.S. Patent No. 4,445,833 [Patent Document 45] U.S. Patent No. 4,717,325 [Patent Document 46] U.S. Patent No. 4,743,189 [Patent Document 47] U.S. Patent No. 5,162,074 [Patent Document 48] U.S. Patent No. 5,256,050 [Patent Document 49] U.S. Patent No. 5,505,889 [Patent Document 50] U.S. Patent No. 5,582,913 [Patent Document 51] U.S. Patent No. 6,670,035 [Patent Document 52] U.S. Patent No. 2,345,543 [Patent Document 53] U.S. Patent No. 2,926,116 [Patent Document 54] U.S. Patent No. 2,926,154 [Patent Document 55] U.S. Patent No. 3,700,623 [Patent Document 56] U.S. Patent No. 3,772,076 [Patent Document 57] U.S. Patent No. 3,556,932 [Patent Document 58] U.S. Patent No. 5,466,337 [Patent Document 59] U.S. Patent No. 3,556,933 [Patent Document 60] U.S. Patent No. 4,605,702 [Patent Document 61] U.S. Patent No. 4,603,176 [Patent Document 62] U.S. Patent No. 5,935,383 [Patent Document 63] U.S. Patent No. 6,017,417 [Patent Document 64] U.S. Patent No. 5,147,343 [Patent Document 65] U.S. Patent No. 5,378,528 [Patent Document 66] U.S. Patent No. 5,795,439 [Patent Document 67] U.S. Patent No. 5,807,916 [Patent Document 68] U.S. Patent No. 5,849,211 [Patent Document 69] U.S. Patent No. 6,403,857 [Patent Document 70] U.S. Patent No. 2,929,154 [Patent Document 71] U.S. Patent No. 3,224,986 [Patent Document 72] U.S. Patent No. 3,332,909 [Patent Document 73] U.S. Patent No. 4,076,673 [Patent Document 74] U.S. Patent No. 3,972,092 [Non-patent literature]

[0006] [Non-Patent Document 1] Watson, P. et al., Canadian Pulp Fibre Morphology: Superiority and Considerations for End Use Potential, The Forestry Chronicle, Vol. 85, No. 3, pp. 401-408, May / June 2009 [Non-patent document 2] Horn, R., Morphology of Pulp Fiber from Hardwoods and Influence on Paper Strength, Research Paper FPL 312, Forest Products Laboratory, US Department of Agriculture (1978) and Bleached Eucalyptus Kraft Pulp ECF Technical Sheet (April 2017) (https: / / www.metsafibre.com / en / Documents / Data-sheets / Cenibra-euca-Eucalyptus.pdf) [Non-patent document 3] AJ Stamm, Forest Products Journal 5(6):413 pages, 1955 Summary of the Invention [Problem to be solved by the invention]

[0007] Thus, there is a certain demand and a continuing need for nonwoven materials to provide low runoff characteristics to reduce or prevent undesirable leakage while exhibiting the desired properties of liquid collection, distribution, and storage. The subject matter of the present disclosure addresses these and other needs. [Means for solving the problem]

[0008] The subject matter of the present disclosure provides improved nonwoven materials that advantageously have low runoff. Such nonwoven materials can include at least one three-dimensionally patterned surface.

[0009] The present disclosure provides an airlaid nonwoven material. Such a material can include a first layer and a second layer. The first layer can include bicomponent fibers. The second layer can be disposed adjacent to the first layer and can include cellulose fibers and bicomponent fibers. The second layer can be bonded to at least a portion of its outer surface using a binder, and at least a portion of the second layer can be patterned. The nonwoven material can have a percent runoff of less than about 5%.

[0010] In some embodiments, the patterning of the second layer can include alternating ridges and valleys, and the ridges can have a higher basis weight than the valleys. The ridges can be about 2 mm to about 4 mm wide, and the valleys can be about 1 mm to about 2.5 mm wide.

[0011] The present disclosure provides an airlaid nonwoven material. Such a material can include a first layer, a second layer, and a third layer. The first layer can include bicomponent fibers. The second layer can be disposed adjacent to the first layer and can include cellulose fibers and bicomponent fibers. The third layer can be disposed adjacent to the second layer and can include cellulose fibers and bicomponent fibers. The third layer can be bonded to at least a portion of its outer surface using a binder. At least a portion of at least one of the first and third layers can be patterned. The nonwoven material can have a percent runoff of less than about 5%.

[0012] In some embodiments, the patterning of at least one of the first and third layers can include alternating ridges and valleys, and the ridges can have a higher basis weight than the valleys. The ridges can be about 2 mm to about 4 mm wide, and the valleys can be about 1 mm to about 2.5 mm wide.

[0013] The present disclosure provides an airlaid nonwoven material. Such a material can include a first layer, a second layer, a third layer, and a layer of superabsorbent polymer. The first layer can include bicomponent fibers. The second layer can be disposed adjacent to the first layer and can include cellulose fibers and bicomponent fibers. The third layer can be disposed adjacent to the second layer and can include eucalyptus fibers and bicomponent fibers. The layer of superabsorbent polymer can be disposed between the second and third layers. The third layer can be bonded to at least a portion of its outer surface using a binder. At least a portion of the first layer can be patterned. The nonwoven material can have a percent runoff of less than about 5%.

[0014] In some embodiments, the patterning of the first layer can include alternating ridges and valleys, and the ridges can have a higher basis weight than the valleys. The ridges can be about 2 mm to about 4 mm wide, and the valleys can be about 1 mm to about 2.5 mm wide.

[0015] The present disclosure provides an airlaid nonwoven material. Such a material can include a first layer and a second layer. The first layer can include synthetic fibers. The second layer can be disposed adjacent to the first layer and can include cellulosic and synthetic fibers. The nonwoven material can have at least a portion of at least one surface patterned. The nonwoven material can have a percent runoff of less than about 5%. In certain embodiments, the nonwoven material can have a percent runoff of less than about 1%.

[0016] In some embodiments, the nonwoven material can further include a third layer, which can be disposed adjacent to the second layer and can include cellulosic and synthetic fibers.

[0017] In some embodiments, the nonwoven material can include a layer of superabsorbent polymer. The layer of superabsorbent polymer can be disposed between the second and third layers.

[0018] In one embodiment, the second layer can be bonded to at least a portion of its outer surface with a bonding agent. In an alternative embodiment, the third layer can be bonded to at least a portion of its outer surface with a bonding agent.

[0019] In some embodiments, the cellulosic fibers of the third layer may comprise eucalyptus fibers.In some embodiments, the synthetic fibers of the first and second layers may comprise bicomponent fibers.

[0020] The present disclosure provides an airlaid nonwoven material. Such a material can include a first layer, a second layer, and a third layer. The first layer can include synthetic fibers. The second layer can be disposed adjacent to the first layer and can include cellulose fibers and synthetic fibers. The third layer can be disposed adjacent to the second layer and can include cellulose fibers and synthetic fibers. The nonwoven material can have at least a portion of at least one surface patterned. The nonwoven material can have a percent runoff of less than about 5%. In certain embodiments, the nonwoven material can have a percent runoff of less than about 1%.

[0021] In some embodiments, the nonwoven material can include a layer of superabsorbent polymer, which can be disposed between the second and third layers.

[0022] In some embodiments, the third layer may be bonded to at least a portion of its outer surface with a binder. In some embodiments, the cellulosic fibers of the third layer may include eucalyptus fibers.

[0023] The present disclosure also provides absorbent articles comprising such nonwoven materials.

[0024] The foregoing has outlined rather broadly the features and technical advantages of the present application in order that the detailed description that follows may be better understood.

[0025] Additional features and advantages of the present application will be described hereinafter, which form the subject of the claims of the present application. It should be appreciated by those skilled in the art that the conception and specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present application. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the present application as set forth in the appended claims. The novel features believed characteristic of the present application, both as to its organization and method of operation, together with further objects and advantages, will be better understood from the following description. [Brief explanation of the drawings]

[0026] [Figure 1A] FIG. 1 is a schematic diagram illustrating the composition of a nonwoven material (Structure 2) prepared according to certain non-limiting embodiments provided in Example 1. [Figure 1B] FIG. 1 is a schematic diagram illustrating the composition of a nonwoven material (Structure 4) prepared according to certain non-limiting embodiments provided in Example 1. [Figure 1C] FIG. 1 is a schematic diagram illustrating the composition of a nonwoven material (Structure 5) prepared according to certain non-limiting embodiments provided in Example 1. [Figure 1D] FIG. 1 is a schematic diagram illustrating the composition of a nonwoven material (Structure 7) prepared according to certain non-limiting embodiments provided in Example 1. [Figure 2] 1 is a graph showing runoff test results for nonwoven materials according to Examples 1 and 2 (Structures 1 and 2). [Figure 3] 1 is a graph showing runoff test results for nonwoven materials according to Examples 1 and 2 (Structures 3-5). [Figure 4] 1 is a graph showing runoff test results for nonwoven materials according to Examples 1 and 2 (Structures 6-7). [Figure 5] 1 is an exemplary image of a nonwoven material formed using a patterned wire (e.g., Ribtech 84, Albany International, Rochester, NH). DETAILED DESCRIPTION OF THE INVENTION

[0027] The subject matter of the present disclosure provides novel low runoff nonwoven materials and methods for making same. The nonwoven material of the present disclosure can include a pattern on at least one surface thereof, which surprisingly and advantageously provides a low-shedding nonwoven material. These and other aspects of the presently disclosed subject matter are further discussed in the detailed description and examples.

[0028] definition The terms used herein have their ordinary meanings in the art, generally within the context of this subject matter and in the specific context in which each term is used. Certain terms are defined below to provide additional guidance in describing the compositions and methods of the presently disclosed subject matter, and how to make and use the same.

[0029] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a "compound" includes a mixture of compounds.

[0030] The term "about" or "approximately" means within an acceptable error range for a particular value as determined by one of ordinary skill in the art, which depends in part on how the value is measured or determined, i.e., the limitations of the measurement system. For example, "about" can mean within 3 or more standard deviations, in accordance with industry practice. Alternatively, "about" can mean within a range of up to 20%, preferably up to 10%, more preferably up to 5%, and more preferably still up to 1% of a given value. Alternatively, particularly with respect to a system or method, the term can mean within an order of magnitude of a value, preferably within 5-fold, and more preferably within 2-fold.

[0031] The term "basis weight" as used herein refers to the amount by mass of a compound over a given area. Examples of units of measure include grams per square meter, identified by the acronym "gsm."

[0032] As used herein, the term "cellulose" or "cellulosic" specifically includes any material having cellulose as a major component, specifically containing at least 50 weight percent cellulose or cellulose derivatives. Thus, the term includes cotton, ordinary wood pulp, cellulose acetate, rayon, thermochemical wood pulp, chemical wood pulp, debonded chemical wood pulp, milkweed floss, microcrystalline cellulose, microfibrillated cellulose, etc.

[0033] As used herein, the phrase "chemical modification," when used with reference to fibers, means that the fibers are treated with a polyvalent metal-containing compound to produce fibers containing the polyvalent metal-containing compound bound thereto. It is not necessary for the compound to be chemically bound to the fibers, but it is preferred that the compound remain in close association with the fibers by coating, adhesion, precipitation, or any other mechanism so that the compound does not migrate from the fibers during normal handling of the fibers. In particular, the compound can remain associated with the fibers even when wetted or washed with a liquid. For convenience, the association between the fibers and the compound can be referred to as a bond, and the compound can be said to be bound to the fibers.

[0034] As used herein, the terms "fibrous" or "fibrous" refer to particulate materials, such particulate materials having a length to diameter ratio of greater than about 10. Conversely, "non-fibrous" or "non-fibrous" materials are meant to refer to particulate materials, such particulate materials having a length to diameter ratio of less than or equal to about 10.

[0035] As used herein, "nonwoven" refers to a type of material, including, but not limited to, textiles or plastics. A nonwoven is a sheet or web structure made of fibers, filaments, fused plastics, or plastic films bonded together mechanically, thermally, or chemically. A nonwoven is a fabric made directly from a web of fibers, without the yarn preparation required for weaving or knitting. In a nonwoven, the collection of fibers is held together by one or more of the following: (1) mechanical interlocking in a random web or mat; (2) fusion of the fibers, as in the case of thermoplastic fibers; or (3) bonding by a bonding medium such as a natural or synthetic resin.

[0036] As used herein, the term "run-off" refers to the tendency of a fluid to overflow the surface of an absorbent material before it can be fully captured by the absorbent. Run-off can be expressed as a percent run-off.

[0037] As used herein, the term "weight percent" is meant to refer to either (i) the amount by weight of a component / ingredient in a material as a weight percentage of a material layer; or (ii) the amount by weight of a component / ingredient in a material as a weight percentage of the final nonwoven material or product.

[0038] fiber The nonwoven material of the presently disclosed subject matter comprises fibers. The fibers may be natural fibers, synthetic fibers, or a mixture thereof. In some embodiments, the fibers may be cellulosic fibers, one or more synthetic fibers, or a mixture thereof.

[0039] cellulose fiber Any naturally occurring cellulose fiber known in the art can be used for the cellulosic layer, including those derived from wood pulp or regenerated cellulose. In some embodiments, the cellulose fibers include digested fibers, such as, but not limited to, kraft fibers, prehydrolyzed kraft fibers, soda fibers, sulfite fibers, chemithermomechanical fibers, and thermomechanically treated fibers, derived from softwoods, hardwoods, or cotton linters. In other embodiments, the cellulose fibers include, but are not limited to, kraft digested fibers, including prehydrolyzed kraft digested fibers. Non-limiting examples of cellulose fibers suitable for use in the present subject matter are cellulose fibers derived from softwoods, such as pine, fir, and spruce. Other suitable cellulose fibers include, but are not limited to, those derived from esparto grass, bagasse, kemp, flax, hemp, kenaf, and other woody and cellulosic fiber sources. Suitable cellulose fibers include, but are not limited to, bleached kraft southern pine fiber sold under the trademark FOLEY FLUFFS® (Buckeye Technologies Inc., Memphis, Tenn.). Additionally, fibers sold under the trademark CELLU TISSUE® (eg, Grade 3024) (Clearwater Paper Corporation, Spokane, Wash.) find use in certain embodiments of the presently disclosed subject matter.

[0040] Nonwoven materials of the presently disclosed subject matter can also include, but are not limited to, commercially available bright fluff pulps, including but not limited to southern softwood kraft (e.g., GP Cellulose's Golden Isles® 4725) or southern softwood fluff pulp (e.g., Treated FOLEY FLUFFS®), northern softwood sulfite pulp (e.g., Weyerhaeuser's T730), or hardwood pulp (e.g., eucalyptus). In some embodiments, the nonwoven material can include eucalyptus fibers (Suzano, untreated). While certain pulps may be preferred based on various factors, any absorbent fluff pulp or mixtures thereof can be used. In some embodiments, wood cellulose, cotton linter pulp, chemically modified cellulose, such as crosslinked cellulose fibers and highly refined cellulose fibers, can be used. Further non-limiting examples of pulps are FOLEY FLUFFS® FFTAS (also known as FFTAS or Buckeye Technologies FFT-AS pulp) and Weyco CF401.

[0041] In some embodiments, fine fibers, such as certain softwood fibers, can be used. Some non-limiting examples of such fine fibers, including pulp coarseness, are provided in Table I below with reference to Watson, P. et al., Canadian Pulp Fibre Morphology: Superiority and Considerations for End Use Potential, The Forestry Chronicle, Vol. 85, No. 3, pp. 401-408, May / June 2009.

[0042] [Table 1]

[0043] In some embodiments, fine fibers, such as certain hardwood fibers, can be used. Some non-limiting examples of such fine fibers, including pulp coarseness, are provided in Table II (Table 2), at least in part, by reference to Horn, R., Morphology of Pulp Fiber from Hardwoods and Influence on Paper Strength, Research Paper FPL 312, Forest Products Laboratory, US Department of Agriculture (1978) and Bleached Eucalyptus Kraft Pulp ECF Technical Sheet (April 2017) (available at: https: / / www.metsafibre.com / en / Documents / Data-sheets / Cenibra-euca-Eucalyptus.pdf). In certain embodiments, eucalyptus pulp (Sunzano, untreated) can be used.

[0044] [Table 2]

[0045] Other suitable types of cellulose fibers include, but are not limited to, chemically modified cellulose fibers. In certain embodiments, the modified cellulose fibers are crosslinked cellulose fibers. U.S. Patent Nos. 5,492,759, 5,601,921, and 6,159,335, all of which are incorporated herein by reference in their entireties, relate to chemically treated cellulose fibers useful in practicing the subject matter of the present disclosure. In certain embodiments, the modified cellulose fibers include a polyhydroxy compound. Non-limiting examples of polyhydroxy compounds include glycerin, trimethylolpropane, pentaerythritol, polyvinyl alcohol, partially hydrolyzed polyvinyl acetate, and fully hydrolyzed polyvinyl acetate. In certain embodiments, the fibers are treated with a polyvalent cation-containing compound. In one embodiment, the polyvalent cation-containing compound is present in an amount of about 0.1 weight percent to about 20 weight percent based on the dry weight of the untreated fiber. In certain embodiments, the polyvalent cation-containing compound is a polyvalent metal ion salt. In certain embodiments, the polyvalent cation-containing compound is selected from the group consisting of aluminum, iron, tin, salts thereof, and mixtures thereof. Any polyvalent metal salt, including transition metal salts, may be used. Non-limiting examples of suitable polyvalent metals include beryllium, magnesium, calcium, strontium, barium, titanium, zirconium, vanadium, chromium, molybdenum, tungsten, manganese, iron, cobalt, nickel, copper, zinc, aluminum, and tin. Preferred ions include aluminum, iron, and tin. Preferred metal ions have an oxidation state of +3 or +4. Any salt containing a polyvalent metal ion may be used. Non-limiting examples of suitable inorganic salts of the above metals include chlorides, nitrates, sulfates, borates, bromides, iodides, fluorides, nitrides, perchlorates, phosphates, hydroxides, sulfides, carbonates, bicarbonates, oxides, alkoxides, phenoxides, phosphites, and hypophosphites.Non-limiting examples of suitable organic salts of the above metals include formate, acetate, butyrate, hexanoate, adipate, citrate, lactate, oxalate, propionate, salicylate, glycinate, tartrate, glycolate, sulfonate, phosphonate, glutamate, octanoate, benzoate, gluconate, maleate, succinate, and 4,5-dihydroxy-benzene-1,3-disulfonate. In addition to polyvalent metal salts, other compounds such as complexes of the above salts include, but are not limited to, amines, ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DIPA), nitrilotriacetic acid (NTA), 2,4-pentanedione, and ammonia.

[0046] In one embodiment, the cellulose pulp fibers are chemically modified cellulose pulp fibers that have been softened or plasticized to make them inherently more compressible than unmodified pulp fibers. The same pressure applied to a plasticized pulp web results in a higher density than when applied to an unmodified pulp web. Furthermore, a densified web of plasticized cellulose fibers is inherently softer than a web of similar density made of unmodified fibers of the same wood type. Softwood pulp may be made more compressible using cationic surfactants as debonders to break down intrafiber associations. The use of one or more debonders facilitates the disintegration of the pulp sheet into fluff during the airlaid process. Examples of debonders include, but are not limited to, those disclosed in U.S. Pat. Nos. 4,432,833, 4,425,186, and 5,776,308, all of which are incorporated herein by reference in their entireties. One example of a debonder-treated cellulose pulp is FFLE+. Plasticizers for cellulose, which can be added to the pulp slurry before the formation of a wet-laid sheet, can also be used to soften the pulp, but they work by a different mechanism than debonders. Plasticizers act on the cellulose molecules within the fiber, making the amorphous regions flexible or soft. The resulting fibers are characterized as soft. Because plasticized fibers lack stiffness, this ground pulp is easier to densify compared to fibers that are not treated with a plasticizer. Plasticizers include, but are not limited to, polyhydric alcohols such as glycerol, low molecular weight polyglycols such as polyethylene glycol, and polyhydroxy compounds. These and other plasticizers are described and exemplified in U.S. Pat. Nos. 4,098,996, 5,547,541, and 4,731,269, all of which are incorporated herein by reference in their entireties. By way of example and not limitation, the plasticizer may be polyethylene glycol 100 (PEG 100), polyethylene glycol 200 (PEG 200), polyethylene glycol 300 (PEG 300), or polyethylene glycol 400 (PEG 400).Ammonia, urea, and alkylamines are also known to plasticize wood products that primarily contain cellulose (AJ Stamm, Forest Products Journal 5(6):413, 1955, incorporated herein by reference in its entirety).

[0047] In certain embodiments of the presently disclosed subject matter, the following celluloses are used: GP 4723, fully treated pulp from Leaf River, eucalyptus pulp (Suzano, untreated), or combinations thereof.

[0048] The nonwoven material of the present disclosure can comprise cellulose fibers. In some embodiments, one or more layers of the nonwoven material can comprise cellulose fibers having a thickness of about 5 gsm to about 150 gsm, about 5 gsm to about 100 gsm, or about 10 gsm to about 50 gsm. In specific embodiments, one or more layers can comprise cellulose fibers having a thickness of about 20 gsm, about 21 gsm, about 21.36 gsm, about 30 gsm, about 40 gsm, about 50 gsm, about 60 gsm, about 62 gsm, about 70 gsm, or about 71 gsm.

[0049] Synthetic fibers In addition to the use of cellulosic fibers, the presently disclosed subject matter also contemplates the use of synthetic fibers. In one embodiment, the synthetic fibers include bicomponent and / or monocomponent fibers. Bicomponent fibers having a core and a sheath are known in the art. Many types, particularly those manufactured for use in airlaid techniques, are used in the fabrication of nonwoven materials. Various bicomponent fibers suitable for use in the presently disclosed subject matter are disclosed in U.S. Pat. Nos. 5,372,885 and 5,456,982, both of which are incorporated herein by reference in their entireties. Examples of bicomponent fiber manufacturers include, but are not limited to, Trevira (Bobingen, Germany), Fiber Innovation Technologies (Johnson City, TN), and ES Fiber Visions (Athens, GA).

[0050] Bicomponent fibers can incorporate a variety of polymers as their core and sheath components. Bicomponent fibers with a PE (polyethylene) or modified PE sheath typically have a PET (polyethylene terephthalate) or PP (polypropylene) core. In one embodiment, the bicomponent fiber has a core made from polyester and a sheath made from polyethylene. In another embodiment, the bicomponent fiber has a core made from polypropylene and a sheath made from polyethylene.

[0051] The denier of the bicomponent fiber preferably ranges from about 1.0 dpf to about 4.0 dpf, more preferably from about 1.5 dpf to about 2.5 dpf. The length of the bicomponent fiber may be from about 3 mm to about 36 mm, preferably from about 3 mm to about 12 mm, more preferably from about 3 mm to about 10 mm. In certain embodiments, the length of the bicomponent fiber is from about 4 mm to about 8 mm, or about 6 mm. In certain embodiments, the bicomponent fiber is Trevira T255, which comprises a polyester core and a maleic anhydride-modified polyethylene sheath. T255 is manufactured in a variety of denier, cut lengths, and core-sheath configurations, with preferred configurations having a denier of about 1.7 dpf to 2.0 dpf, a cut length of about 4 mm to 12 mm, and a concentric core-sheath configuration. In a specific embodiment, the bicomponent fiber is Trevira 1661, T255, 2.0 dpf, and 6 mm length.

[0052] Bicomponent fibers are typically commercially produced by melt spinning. In this procedure, each molten polymer is extruded through a die, e.g., a spinneret, and then pulled to remove it from the face of the spinneret. This is followed by solidification of the polymer by heat transfer to a surrounding fluid medium, e.g., quenched air, and then winding of the solid filaments. Non-limiting examples of further steps after melt spinning include hot or cold drawing, heat treatment, crimping, and cutting. This overall fabrication process is generally carried out as a discontinuous two-step process, first involving spinning of filaments and their converging into a tow containing multiple filaments. During the spinning step, some stretching of the filaments does occur as the molten polymer is pulled away from the face of the spinneret, which may also be called drawdown. This is followed by a second step in which the spun fiber is drawn or stretched to increase molecular alignment and crystallinity, imparting enhanced strength and other physical properties to the individual filaments. Subsequent steps can include, but are not limited to, heat setting, crimping, and cutting the filaments into fibers. The drawing or stretching step can involve stretching the core of a bicomponent fiber, the sheath of a bicomponent fiber, or both the core and sheath of a bicomponent fiber, depending on the materials comprised by the core and sheath and the conditions used during the drawing or stretching process.

[0053] Bicomponent fibers can also be formed in a continuous process, where spinning and drawing are performed in a continuous process. During the fiber fabrication process, it may be desirable to add various materials to the fiber after the melt-spinning step at various subsequent steps in the process. These materials may be referred to as "finishes" and include, but are not limited to, active agents such as lubricants and antistatic agents. Finishes are typically applied via aqueous-based solutions or emulsions. Finishes can impart desirable properties for both the fabrication of the bicomponent fiber and the user of the fiber, for example, in airlaid or wetlaid processes.

[0054] Numerous other processes are involved before, during, and after the spinning and drawing steps, as seen in U.S. Pat. No. 4,950,541, U.S. Pat. No. 5,082,899, U.S. Pat. No. 5,126,199, U.S. Pat. No. 5,372,885, U.S. Pat. No. 5,456,982, U.S. Pat. No. 5,705,565, U.S. Pat. No. 2,861,319, U.S. Pat. No. 2,931,091, U.S. Pat. No. 2,989,798, U.S. Pat. No. 3,038, 235, U.S. Patent No. 3,081,490, U.S. Patent No. 3,117,362, U.S. Patent No. 3,121,254, U.S. Patent No. 3,188,689, U.S. Patent No. 3,237,245, U.S. Patent No. 3,249,669, U.S. Patent No. 3,457,342, U.S. Patent No. 3,466,703, U.S. Patent No. 3,469,279, U.S. Patent No. 3,500,498, U.S. Patent No. 3,585,685, U.S. Patent No. Nos. 3,163,170, 3,692,423, 3,716,317, 3,778,208, 3,787,162, 3,814,561, 3,963,406, 3,992,499, 4,052,146, 4,251,200, 4,350,006, and 4,370,114. Nos. 4,406,850, 4,445,833, 4,717,325, 4,743,189, 5,162,074, 5,256,050, 5,505,889, 5,582,913, and 6,670,035, all of which are incorporated herein by reference in their entireties.

[0055] The subject matter of the present disclosure can also include, but is not limited to, articles containing partially drawn bicomponent fibers with varying degrees of stretch or elongation, highly drawn bicomponent fibers, and mixtures thereof. These can include, but are not limited to, highly drawn polyester core bicomponent fibers with various sheath materials, specifically including a polyethylene sheath, such as Trevira T255 (Bobingen, Germany), or highly drawn polypropylene core bicomponent fibers with various sheath materials, specifically including a polyethylene sheath, such as ES FiberVisions AL-Adhesion-C (Varde, Denmark). Additionally, Trevira T265 bicomponent fibers (Bobingen, Germany) can be used, which have a partially drawn core with a core made of polybutylene terephthalate (PBT) and a sheath made of polyethylene. The use of both partially drawn and highly drawn bicomponent fibers in the same structure can be exploited to meet specific physical and performance properties based on how they are incorporated into the structure.

[0056] The bicomponent fibers of the presently disclosed subject matter are not limited in scope to any particular polymer for either the core or sheath, as any partially drawn core bicomponent fiber can provide enhanced performance in terms of elongation and strength. The extent to which partially drawn bicomponent fibers are drawn is not limited in scope, as different degrees of drawing result in different enhancements in performance. The scope of partially drawn bicomponent fibers encompasses fibers with various core-sheath configurations, including, but not limited to, concentric, eccentric, side-by-side, islands-in-the-sea, pie-split, and other variations. The relative weight percentages of the core and sheath components of the total fiber can vary. Additionally, the scope of the present subject matter extends to the use of partially drawn homopolymers such as polyester, polypropylene, nylon, and other melt-spinnable polymers. The scope of the present subject matter also extends to multicomponent fibers that may have three or more polymers as part of the fiber structure.

[0057] In certain embodiments, the bicomponent fibers are low dtex staple bicomponent fibers ranging from about 0.5 dtex to about 20 dtex. In some embodiments, the dtex value may range from about 1.3 dtex to about 15 dtex, from about 1.5 dtex to about 10 dtex, from about 1.7 dtex to about 6.7 dtex, or from about 2.2 dtex to about 5.7 dtex. In some embodiments, the dtex value may be about 1.3 dtex, about 1.5 dtex, about 1.7 dtex, about 2.2 dtex, about 3.3 dtex, about 5.7 dtex, about 6.7 dtex, or about 10 dtex. In some embodiments, the bicomponent fibers are web-forming staple fibers.

[0058] Other synthetic fibers suitable for use in various embodiments as fibers or as bicomponent binder fibers include, by way of example and not limitation, acrylics, polyamides (including but not limited to nylon 6, nylon 6 / 6, nylon 12, polyaspartic acid, polyglutamic acid), polyamines, polyimides, polyacrylic acids (including but not limited to polyacrylamide, polyacrylonitrile, esters of methacrylic acid and acrylic acid), polycarbonates (including but not limited to polybisphenol A carbonate, polypropylene carbonate), polydienes (including but not limited to polybutadiene, polyisoprene, polynorbornene), polyepoxides, polyesters (including but not limited to polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polycaprolactone, polyglycolide, polylactide, polyhydroxybutyrate, polyhydroxyvalerate, polyethylene adipate, polybutylene adipate, polypropylene succinate), polyethers (polyethylene glycol (polyethylene oxide) , polybutylene glycol, polypropylene oxide, polyoxymethylene (paraformaldehyde), polytetramethylene ether (polytetrahydrofuran), polyepichlorohydrin), polyfluorocarbons, formaldehyde polymers (including but not limited to urea-formaldehyde, melamine-formaldehyde, phenol formaldehyde), natural polymers (including but not limited to cellulosics, chitosan, lignin, waxes), polyolefins (polyethylene, polypropylene, polybutene, Polyethylenes (including but not limited to, polyethylene, polybutene, polyoctene), polyphenylenes (including but not limited to, polyphenylene oxide, polyphenylene sulfide, polyphenylene ether sulfone), silicon-containing polymers (including but not limited to, polydimethylsiloxane, polycarbomethylsilane), polyurethanes, polyvinyls (including but not limited to, polyvinyl butyral, polyvinyl alcohol, esters and ethers of polyvinyl alcohol, polyvinyl acetate, polystyrene, polymethylstyrene, polyvinyl chloride, polyvinylpyrrolidone,These include, but are not limited to, fibers made from a variety of polymers, including but not limited to, polymethyl vinyl ether, polyethyl vinyl ether, polyvinyl methyl ketone), polyacetals, polyarylates, and copolymers (including but not limited to polyethylene-co-vinyl acetate, polyethylene-co-acrylic acid, polybutylene terephthalate-co-polyethylene terephthalate, polylauryllactam-block-polytetrahydrofuran), polybutylene succinate, and polylactic acid-based polymers.

[0059] In specific embodiments, the synthetic fiber layer comprises high dtex staple fibers ranging from about 2 to about 20 dtex. In some embodiments, the dtex value may range from about 2 dtex to about 15 dtex, or from about 2 dtex to about 10 dtex. In certain embodiments, the fibers may have a dtex value of about 6.7 dtex.

[0060] In other specific embodiments, the synthetic layer comprises synthetic filaments. The synthetic filaments can be formed by a spinning and / or extrusion process. For example, such processes can be similar to those described above with respect to the melt-spinning process. The synthetic filaments can comprise one or more continuous strands. In some embodiments, the synthetic filaments can comprise polypropylene.

[0061] In certain embodiments of the presently disclosed subject matter, the following synthetic fibers are used: Trevira Type 255, 6.7 dtex, 6 mm, PE / PET; Trevira Type 245, 6.7 dtex, 3 mm; Trevira PE / PET 70% core, 1.7 dtex, 6 mm; Trevira PE / PET 30% core, 1.5 dtex, 6 mm; or combinations thereof.

[0062] The nonwoven material of the present disclosure can comprise synthetic fibers. In some embodiments, one or more layers of the nonwoven material can comprise synthetic fibers of about 1 gsm to about 40 gsm, about 5 gsm to about 30 gsm, or about 10 gsm to about 25 gsm. In specific embodiments, one or more layers of the nonwoven material can comprise synthetic fibers of about 6 gsm, about 6.28 gsm, about 8 gsm, about 10 gsm, about 25 gsm, about 26 gsm, about 26.34 gsm, or about 27 gsm.

[0063] Binder In some embodiments, the nonwoven materials described herein may include a binder. Suitable binders include, but are not limited to, liquid binders and powder binders. Non-limiting examples of liquid binders include emulsions, solutions, or suspensions of binders. Non-limiting examples of binders include polyethylene powder, copolymer binders, vinyl acetate ethylene binders, styrene-butadiene binders, urethanes, urethane-based binders, acrylic binders, thermoplastic binders, natural polymer-based binders, and mixtures thereof.

[0064] Suitable binders include copolymers, vinyl acetate ethylene ("VAE") copolymers, which may have stabilizers such as Wacker Vinnapas 192, Wacker Vinnapas EF 539, Wacker Vinnapas EP907, Wacker Vinnapas EP129, Celanese Duroset El30, Celanese Dur-O-Set Elite 130 25-1813, and Celanese Dur-O-Set TX-849, Celanese 75-524A, polyvinyl alcohol-polyvinyl acetate blends such as Wacker Vinac 911, vinyl acetate homopolymers, polyvinylamines such as BASF Luredur, acrylic resins, cationic acrylamides, polyacrylamides such as Bercon Berstrength 5040 and Bercon Berstrength 5150, hydroxyethyl cellulose, National Starch CATO R™ 232, National Examples of suitable binders include, but are not limited to, starch, guar gum, styrene-butadiene, urethane, urethane-based binders, thermoplastic binders, acrylic binders, such as National Starch CATO R™ 255, National Starch Optibond, National Starch Optipro, or National Starch OptiPLUS, and carboxymethylcellulose, such as Hercules Aqualon CMC. In some embodiments, the binder is a natural polymer binder. Non-limiting examples of natural polymer binders include polymers derived from starch, cellulose, chitin, and other polysaccharides.

[0065] In some embodiments, the binder is water-soluble. In one embodiment, the binder is a vinyl acetate ethylene copolymer. One non-limiting example of such a copolymer is EP907 (Wacker Chemicals, Munich, Germany). Vinnapas EP907 can be applied at a level of about 10% solids incorporating about 0.75% by weight of Aerosol OT (Cytec Industries, West Paterson, NJ), an anionic surfactant. Other classes of liquid binders, such as styrene-butadiene and acrylic binders, can also be used. In some embodiments, Vinnapas 192 can be applied at a level of about 15% incorporating about 0.08% by weight of Aerosol OT 75 (Cytec Industries, West Paterson, NJ).

[0066] In some embodiments, the binder is not water-soluble. Examples of these binders include, but are not limited to, Vinnapas 124 and 192 (Wacker), which may have opacifiers and whiteners, including, but not limited to, titanium dioxide dispersed in the emulsion. Other binders include, but are not limited to, Celanese Emulsions (Bridgewater, NJ) Elite 22 and Elite 33.

[0067] In some embodiments, the binder is a thermoplastic binder. Such thermoplastic binders include, but are not limited to, any thermoplastic polymer that can be melted at a temperature that does not significantly damage the cellulose fibers. Preferably, the melting point of the thermoplastic binder is less than about 175°C. Examples of suitable thermoplastic materials include, but are not limited to, thermoplastic binders and suspensions of thermoplastic powders. In certain embodiments, the thermoplastic binder may be, for example, polyethylene, polypropylene, polyvinyl chloride, and / or polyvinylidene chloride.

[0068] In certain embodiments, the vinyl acetate ethylene binder is non-crosslinkable. In one embodiment, the vinyl acetate ethylene binder is crosslinkable. In some embodiments, the binder is WD4047 urethane-based binder solution supplied by HB Fuller. In one embodiment, the binder is Michem Prime 4983-45N dispersion of ethylene acrylic acid ("EAA") supplied by Michelman. In some embodiments, the binder is Dur-O-Set Elite 22LV emulsion, a VAE binder supplied by Celanese Emulsions, Inc. (Bridgewater, NJ). As noted above, in certain embodiments, the binder is crosslinkable. It is understood that crosslinkable binders are also known as permanent wet strength binders. Permanent wet strength binders include, but are not limited to, Kymene® (Hercules Inc., Wilmington, Del.), Parez® (American Cyanamid Company, Wayne, NJ), Wacker Vinnapas or AF192 (Wacker Chemie AG, Munich, Germany), and the like. Various permanent wet strength agents are described in U.S. Pat. Nos. 2,345,543, 2,926,116, and 2,926,154, the disclosures of which are incorporated herein by reference in their entireties. Other permanent wet strength binders include, but are not limited to, polyamine-epichlorohydrin, polyamide-epichlorohydrin, or polyamide-amine-epichlorohydrin resins, collectively referred to as "PAE resins." Non-limiting exemplary permanent wet strength binders include Kymene 557H or Kymene 557LX (Hercules Inc., Wilmington, Del.), and are described in U.S. Pat. Nos. 3,700,623 and 3,772,076, which are incorporated herein by reference in their entireties.

[0069] Alternatively, in some embodiments, the binder is a temporary wet strength binder, including, but not limited to, Hercobond® (Hercules Inc., Wilmington, Del.), Parez® 750 (American Cyanamid Company, Wayne, NJ), Parez® 745 (American Cyanamid Company, Wayne, NJ), and the like. Other suitable temporary wet strength binders include, but are not limited to, dialdehyde starch, polyethyleneimine, mannogalactan gum, glyoxal, and dialdehyde mannogalactan. Other suitable temporary wet strength agents are described in U.S. Pat. No. 3,556,932, U.S. Pat. No. 5,466,337, U.S. Pat. No. 3,556,933, U.S. Pat. No. 4,605,702, U.S. Pat. No. 4,603,176, U.S. Pat. No. 5,935,383, and U.S. Pat. No. 6,017,417, all of which are incorporated herein by reference in their entireties.

[0070] In certain embodiments of the presently disclosed subject matter, the following binders are used: Vinnapas 192 (Wacker) containing 0.20 gsm of surfactant Aerosol OT 75 (Cytec Industries), or Vinnapas 192 (Wacker) containing 0.8% surfactant Aerosol OT 75 (Cytec Industries).

[0071] In some embodiments, the binder can be applied as an emulsion in an amount ranging from about 1 gsm to about 10 gsm, about 1 gsm to about 8 gsm, about 1 gsm to about 5 gsm, about 1 gsm to about 4 gsm, about 5 gsm to about 10 gsm, about 2 gsm to about 5 gsm, or about 2 gsm to about 3 gsm. In certain embodiments, the binder can be applied as an emulsion in an amount of about 1 gsm, about 2 gsm, about 3 gsm, about 4 gsm, about 5 gsm, about 6 gsm, or about 6.02 gsm. The binder can be applied to one side of the fibrous layer, preferably the exterior-facing layer. Alternatively, the binder can be applied to both sides of the layer in equal or disproportionate amounts. In some embodiments, the binder can be applied to at least one outer surface of the nonwoven material. In certain embodiments, the binder can be applied to at least two outer surfaces of the nonwoven material.

[0072] Other additives The materials of the presently disclosed subject matter can also contain other additives. For example, the materials can include superabsorbent polymers (SAPs). Types of superabsorbent polymers that may be used in the presently disclosed subject matter include, but are not limited to, SAPs in particulate form, such as powders, irregular granules, spherical particles, staple fibers, and other elongated particles. U.S. Patent Nos. 5,147,343, 5,378,528, 5,795,439, 5,807,916, 5,849,211, and 6,403,857, all of which are hereby incorporated by reference in their entireties, describe various superabsorbent polymers and methods of making them. One example of a superabsorbent polymer-forming system is a crosslinked acrylic copolymer of a metal salt of acrylic acid with other monomers, such as acrylamide or 2-acrylamido-2-methylpropanesulfonic acid. Many conventional granular superabsorbent polymers are based on poly(acrylic acid) crosslinked during polymerization with any of several multifunctional comonomer crosslinkers known in the art. Examples of multifunctional crosslinkers are described in U.S. Pat. Nos. 2,929,154, 3,224,986, 3,332,909, and 4,076,673, which are incorporated herein by reference in their entireties. For example, crosslinked carboxylated polyelectrolytes can be used to form superabsorbent polymers. Other water-soluble polyelectrolyte polymers are known to be useful for preparing superabsorbents by crosslinking, including carboxymethyl starch, carboxymethyl cellulose, chitosan salts, gelatin salts, and the like. However, they are not generally used on a commercial scale to enhance the absorbency of disposable absorbent articles, primarily due to their relatively high cost. Superabsorbent polymer granules useful in the practice of the present subject matter are commercially available from several manufacturers, such as BASF, Dow Chemical (Midland, Mich.), Stockhausen (Greensboro, NC), Chemdal (Arlington Heights, Ill.), and Evonik (Essen, Germany).Non-limiting examples of SAPs include surface cross-linked acrylic acid based powders such as Stockhausen 9350 or SX70, BASF Hysorb Fem 33, BASF HySorb FEM 33N, or Evonik Favor SXM 7900.

[0073] In certain embodiments of the presently disclosed subject matter, the following additive is used: Evonik Favor SXM 7900.

[0074] In some embodiments, other additives may be used in a layer in an amount ranging from about 5% to about 50% based on the total weight of the structure. In some embodiments, the content of other additives is between about 0% and about 30%, about 0% and about 15%, about 5% and about 25%, about 5% and about 15%, or about 10% and about 20% based on the total weight of the structure. In certain embodiments, the content of other additives may be about 0%, about 2%, about 5%, about 8%, about 10%, about 15%, about 20%, about 25%, or about 30% based on the total weight of the structure. In some embodiments, the amount of additive in a layer may range from about 5 gsm to about 50 gsm, about 5 gsm to about 25 gsm, about 10 gsm to about 50 gsm, about 12 gsm to about 40 gsm, or about 15 gsm to about 25 gsm. In certain embodiments, the amount of other additives may be about 10 gsm based on the total weight of the structure. For example, in one embodiment, the nonwoven material can include SAP in an amount of about 10 gsm.

[0075] nonwoven material The subject matter of the present disclosure provides a nonwoven material with reduced runoff. Such a nonwoven material can include a three-dimensional pattern on at least one surface. As embodied herein, the nonwoven material can include at least one layer, at least two layers, or at least three layers. In some embodiments, the nonwoven material can include four or more layers. In certain embodiments, the nonwoven material includes two or three layers. As further embodied herein, the nonwoven material can be an airlaid material. In certain embodiments, the nonwoven material can be an absorbent structure for liquid collection and temporary storage; liquid collection, distribution, and permanent storage; or liquid distribution and permanent storage.

[0076] The nonwoven material of the present disclosure may be an absorbent structure for liquid collection and temporary storage. In some embodiments, the nonwoven material can have at least one layer. The at least one layer can include cellulosic fibers, synthetic fibers, or a combination thereof. In some embodiments, the nonwoven material can have at least two layers. In such embodiments, the nonwoven material can include at least one layer including synthetic fibers, such as bonded synthetic fibers, such as bicomponent fibers, monocomponent fibers, staple fibers, or staple fibers that form prefabricated fibrous webs in a carding process. The nonwoven material can further include an additional layer including bonded synthetic fibers, such as eccentric bicomponent fibers, monocomponent fibers, or staple fibers that form prefabricated fibrous webs in a carding process. In certain embodiments, at least one layer can further include cellulosic fibers, such as softwood or hardwood fibers. In some embodiments, at least one layer includes synthetic fibers, such as bicomponent or monocomponent synthetic fibers, and can be bonded using a binder. The binder can be applied, for example, by spraying and drying a binder emulsion. The nonwoven material can further include a three-dimensional pattern on at least one surface of the nonwoven material. In some embodiments, the nonwoven material can include a three-dimensional pattern on the bottom or lower surface. In alternative embodiments, the nonwoven material can include a three-dimensional pattern on the top or upper surface.

[0077] The nonwoven material of the present disclosure can be used as an absorbent structure for liquid collection, distribution, and permanent storage. In some embodiments, the nonwoven material can have at least one layer. The at least one layer can include cellulosic fibers, synthetic fibers, or a combination thereof. In some embodiments, the nonwoven material can have at least two layers. In such embodiments, the nonwoven material can include at least one layer including bonded synthetic fibers, such as eccentric bicomponent fibers, monocomponent fibers, or staple fibers forming a prefabricated fibrous web in a carding process. In some embodiments, the nonwoven material can further include at least one layer including cellulosic fibers, such as softwood or hardwood fibers. In certain embodiments, at least one layer of the nonwoven material includes wood fibers having a coarseness of less than 15 mg / 100 m, such as eucalyptus fibers. In such embodiments, the layer including cellulosic fibers can be the lower or bottom layer of the nonwoven material. In certain embodiments, the nonwoven material can include a lower or bottom layer including cellulosic fibers, such as softwood or hardwood fibers. In certain embodiments, the nonwoven material may include a lower or bottom layer comprising wood fibers having a coarseness of less than about 15 mg / 100 m, such as eucalyptus fibers. At least one layer comprising cellulosic fibers may further comprise synthetic fibers and may be bonded using a binder. The binder may be applied, for example, by spraying and drying a binder emulsion. In some embodiments, the nonwoven material may include a three-dimensional pattern on the bottom or lower surface. In alternative embodiments, the nonwoven material may include a three-dimensional pattern on the upper or upper surface. Such nonwoven materials may further include an intermediate layer disposed between the layers. In some embodiments, the intermediate layer may comprise cellulosic fibers. In certain embodiments, the intermediate layer may comprise cellulosic fibers combined with bicomponent fibers. Such intermediate layers may further include one or more additives. In some embodiments, the one or more additives may include superabsorbent particles (SAPs) in the form of granules or fibers.The superabsorbent particles (SAPs) can be blended with cellulosic and / or synthetic fibers, or they can form one or more layers disposed between other layers of the nonwoven structure.

[0078] The nonwoven material of the present disclosure can be made into an absorbent structure for liquid distribution and permanent storage. In some embodiments, the nonwoven material can have at least one layer. The nonwoven material can include at least one layer comprising cellulosic fibers combined with bicomponent fibers. At least one surface of the nonwoven structure can be bonded using a binder. In certain embodiments, at least two surfaces of the nonwoven structure can be bonded using a binder. The binder can be applied, for example, by spraying and drying a binder emulsion. In some embodiments, the nonwoven material can further include one or more additives. In some embodiments, the one or more additives can include superabsorbent particles (SAPs) in the form of granules or fibers. The superabsorbent particles (SAPs) can be blended with cellulosic fibers and / or synthetic fibers, or they can form one or more layers disposed between other layers of the nonwoven structure. In some embodiments, the nonwoven material can include a three-dimensional pattern on the bottom or lower surface. In alternative embodiments, the nonwoven material can include a three-dimensional pattern on the top or upper surface.

[0079] In some embodiments, the nonwoven material can be coated with a binder on at least a portion of its outer surface. While the binder need not be chemically bonded to a portion of the layer, it is preferred that it remain closely associated with the layer by coating, adhesion, precipitation, or any other mechanism so as not to migrate from the layer during normal handling of the layer. For convenience, the association between the layer and the binder discussed above can be referred to as a bond, and the compound can be said to be bonded to the layer. When present, the binder can be applied in an amount ranging from about 1 gsm to about 15 gsm, or from about 2 gsm to about 10 gsm, or from about 2 gsm to about 8 gsm, or from about 3 gsm to about 5 gsm. The binder can be applied to one side of the fibrous layer, preferably the exterior-facing layer. In some embodiments, the binder can be applied to at least one outer surface of the nonwoven material.

[0080] In certain embodiments, the nonwoven material comprises at least two layers, each layer comprising a particular fiber content. In certain embodiments, the nonwoven material may be a two-layer nonwoven structure. The nonwoven material may comprise a synthetic fiber layer and a blend layer comprising cellulosic and synthetic fibers. The first layer may comprise synthetic fibers, such as bicomponent fibers. In certain embodiments, the first layer may comprise eccentric bicomponent fibers. The second layer may be disposed adjacent to the first layer. The second layer may comprise a blend of cellulosic and synthetic fibers. In certain embodiments, the second layer may comprise a blend of cellulosic and bicomponent fibers. The second layer may be bonded to at least a portion of its outer surface using a binder.

[0081] In certain embodiments, the nonwoven material includes at least three layers, each layer including a specific fiber content. In certain embodiments, the nonwoven material may be a three-layer nonwoven structure. The nonwoven material may include a synthetic fiber layer and at least one layer including a blend of cellulosic and bicomponent fibers. In some embodiments, at least one layer includes cellulosic fibers, including eucalyptus fibers. The first layer may include synthetic fibers, such as bicomponent fibers. In certain embodiments, the first layer may include eccentric bicomponent fibers. The second and third layers may include a blend of cellulosic and synthetic fibers. In certain embodiments, the second and third layers may include a blend of cellulosic and bicomponent fibers. In some embodiments, the cellulosic fibers of the third layer may include wood fibers having a coarseness of less than about 15 mg / 100 m, such as eucalyptus fibers. The third layer may be bonded to at least a portion of its outer surface using a binder.

[0082] In certain embodiments, the nonwoven material includes at least three layers, each layer including a specific fiber content. In certain embodiments, the nonwoven material may be a three-layer nonwoven structure. The nonwoven material may include a synthetic fiber layer and at least one layer including a blend of cellulosic and bicomponent fibers. In some embodiments, the nonwoven material may further include one or more additives, such as a superabsorbent polymer (SAP). The first layer may include synthetic fibers, such as bicomponent fibers. In certain embodiments, the first layer may include eccentric bicomponent fibers. The second and third layers may include a blend of cellulosic and synthetic fibers. In certain embodiments, the second and third layers may include a blend of cellulosic and bicomponent fibers. In some embodiments, the cellulosic fibers of the third layer may include wood fibers having a coarseness of less than about 15 mg / 100 m, such as eucalyptus fibers. The third layer may be bonded to at least a portion of its outer surface using a binder. In some embodiments, the nonwoven material can further include one or more layers of additives disposed between the second and third layers. In certain embodiments, the one or more additives can include a superabsorbent polymer (SAP).

[0083] The nonwoven material of the present disclosure can include at least two or at least three layers, each layer containing a specific fiber content. In some embodiments, the first layer can contain synthetic fibers in an amount of about 5 gsm to about 60 gsm, about 10 gsm to about 50 gsm, or about 15 gsm to about 30 gsm. In certain embodiments, the first layer can contain synthetic fibers in an amount of about 20 gsm, about 25 gsm, about 26 gsm, or about 26.34 gsm. In some embodiments, the second layer can contain a blend of cellulosic fibers and bicomponent fibers. The cellulosic fibers can be present in the second layer in an amount of about 10 gsm to about 90 gsm, about 15 gsm to about 80 gsm, or about 50 gsm to about 75 gsm. In certain embodiments, the first layer can contain cellulosic fibers in an amount of about 20 gsm, about 21 gsm, about 25 gsm, about 50 gsm, about 62 gsm, or about 71 gsm. The synthetic fibers can be present in the second layer in an amount of about 1 gsm to about 50 gsm, about 5 gsm to about 35 gsm, or about 5 gsm to about 30 gsm. In certain embodiments, the first layer can comprise about 5 gsm, about 6 gsm, about 15 gsm, about 20 gsm, or about 27 gsm of synthetic fibers. In some embodiments, the third layer can comprise a blend of cellulosic fibers and bicomponent fibers. The cellulosic fibers can be present in the third layer in an amount of about 10 gsm to about 90 gsm, about 15 gsm to about 80 gsm, or about 50 gsm to about 75 gsm. In certain embodiments, the first layer can comprise about 20 gsm, about 21 gsm, about 25 gsm, about 50 gsm, about 62 gsm, or about 71 gsm of cellulosic fibers. The synthetic fibers can be present in the third layer in an amount of about 1 gsm to about 50 gsm, about 5 gsm to about 35 gsm, or about 5 gsm to about 30 gsm. In certain embodiments, the first layer can include about 5 gsm, about 6 gsm, about 8 gsm, about 15 gsm, about 20 gsm, or about 27 gsm synthetic fibers.

[0084] In certain embodiments, the nonwoven material can include one or more additives, such as a superabsorbent polymer (SAP), disposed between the second and third layers. For example, and without limitation, the one or more additives can be present in an amount of about 5 gsm to about 30 gsm, about 15 gsm to about 25 gsm, or about 10 gsm to about 20 gsm. In some embodiments, the nonwoven material can include about 10 gsm of superabsorbent polymer (SAP) disposed between the second and third layers.

[0085] Overall, the layer of nonwoven material can have a basis weight of about 5 gsm to about 250 gsm, or about 30 gsm to about 200 gsm, or about 50 gsm to about 150 gsm, or about 50 gsm to about 65 gsm. In certain embodiments, the layer of nonwoven material can have a basis weight of about 10 gsm, about 20 gsm, about 30 gsm, about 40 gsm, about 60 gsm, about 80 gsm, about 200 gsm, or about 210 gsm.

[0086] Microstructural features of nonwoven materials The nonwoven material of the present disclosure can have a three-dimensional surface microstructure. For example, and not by way of limitation, the nonwoven material can have a pattern on at least one surface. In some embodiments, the nonwoven material can have a pattern on the upper or top surface. In some embodiments, the nonwoven material can have a pattern on the lower or bottom surface. In certain embodiments, the nonwoven material can have a pattern on at least two surfaces. The patterning can include "ridges" and "valleys." In some embodiments, the ridges and valleys can be staggered. In some embodiments, the ridges can run in the cross direction (CD). In alternative embodiments, the ridges can run in the machine direction (MD). The ridges can have a higher basis weight relative to the valleys of the pattern. Thus, the pattern can include regions of low and high basis weight nonwoven material, forming indentations of various shapes. For example, and not by way of limitation, the pattern can include continuous or dotted shapes in various directions, dots of various sizes, etc. The valleys of the pattern may be about 1 mm to about 2.5 mm, about 1 mm to about 2 mm, or about 1.3 mm wide. In some embodiments, the valleys may be at least about 2.5 mm, at least about 2 mm, at least about 1.3 mm, or at least about 1 mm wide. The ridges of the pattern may be about 2 mm to about 4 mm, about 2.1 mm to about 2.8 mm, or about 2.6 mm wide. In some embodiments, the ridges may be at least about 4 mm, at least about 2.8 mm, at least about 2.6 mm, at least about 2.1 mm, or at least about 2 mm wide. In certain embodiments, the nonwoven material can include a three-dimensional pattern, such as that shown in FIG. 1A. The patterning can be imparted, for example, by a forming fabric having a three-dimensional microstructure, e.g., a forming fabric including ridges running transversely across the forming fabric. An exemplary image of a nonwoven material formed using a patterned wire (e.g., Ribtech 84, Albany International, Rochester, NH) is shown in FIG. 5.

[0087] The nonwoven material of the present disclosure advantageously has low runoff. Such nonwoven materials can also have suitable liquid collection, distribution, and storage properties. The nonwoven material of the present disclosure can include a three-dimensional pattern on at least one surface thereof. Such patterning can impart low runoff characteristics to the nonwoven material while simultaneously enabling desired liquid collection, distribution, and storage properties.

[0088] The nonwoven material of the present disclosure can have low runoff. Such low runoff can be imparted to the nonwoven material of the present disclosure by a three-dimensional pattern on at least one surface of the nonwoven material. Specifically, the nonwoven material of the present disclosure can have a low percent runoff. In some embodiments, the nonwoven material of the present disclosure can have a percent runoff of about 0% to about 30%, about 1% to about 30%, about 1% to about 10%, or about 1% to about 5%. In certain embodiments, the nonwoven material of the present disclosure can have a percent runoff of about 1%, about 2%, about 3%, about 4%, about 5%, about 10%, or about 15%. In some embodiments, the nonwoven material of the present disclosure can have a percent runoff of less than about 20%, less than about 15%, less than about 10%, less than about 5%, less than about 4%, less than about 3%, less than about 2%, or less than about 1%.

[0089] In certain embodiments, the nonwoven material can include two layers. The first layer can include synthetic fibers, such as eccentric bicomponent fibers (e.g., Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). For example, the first layer can include eccentric bicomponent fibers of about 5 gsm to about 60 gsm, about 10 gsm to about 50 gsm, or about 26.34 gsm. The second layer can include a blend of cellulosic fibers (e.g., GP 4723, Leaf River fully treated pulp) and synthetic fibers, such as bicomponent fibers (e.g., PET, Trevira Type 245, 6.7 dtex, 3 mm). For example, the second layer can include cellulosic fibers of about 10 gsm to about 90 gsm, about 15 gsm to about 80 gsm, or about 21.36 gsm, and bicomponent fibers of about 1 gsm to about 50 gsm, about 5 gsm to about 35 gsm, or about 6.28 gsm. The outer surface of the second layer can be coated with a binder in the form of an emulsion (e.g., Vinnapas 192 (Wacker) containing 0.20 gsm of surfactant Aerosol OT 75 (Cytec Industries)). For example, the second layer can be coated with a binder in an amount of about 1 gsm to about 10 gsm, about 1 gsm to about 8 gsm, or about 6.02 gsm. At least a portion of the outer surface of the second layer can be patterned. For example, but not by way of limitation, the total basis weight of the nonwoven material can be about 60 gsm.

[0090] In certain embodiments, the nonwoven material can include three layers. The first layer can include synthetic fibers, such as eccentric bicomponent fibers (e.g., Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). For example, the first layer can include eccentric bicomponent fibers of about 50 gsm to about 60 gsm, about 10 gsm to about 50 gsm, or about 25 gsm. The second layer can include a blend of cellulosic fibers (e.g., GP 4723, Leaf River fully treated pulp) and synthetic fibers, such as bicomponent fibers (e.g., Trevira PE / PET 70% core, 1.7 dtex, 6 mm). For example, the second layer can include cellulosic fibers of about 10 gsm to about 90 gsm, about 15 gsm to about 80 gsm, or about 71 gsm, and bicomponent fibers of about 1 gsm to about 50 gsm, about 5 gsm to about 35 gsm, or about 27 gsm. The third layer can comprise a blend of cellulosic fibers (e.g., eucalyptus pulp, Suzano, untreated) and synthetic fibers, such as bicomponent fibers (e.g., Trevira PE / PET 30% core, 1.5 dtex, 6 mm). For example, the third layer can comprise about 10 gsm to about 90 gsm, about 15 gsm to about 80 gsm, or about 62 gsm cellulosic fibers and about 1 gsm to about 50 gsm, about 5 gsm to about 35 gsm, or about 8 gsm bicomponent fibers. The outer surface of the third layer can be coated with a binder in the form of an emulsion (e.g., Vinnapas 192 (Wacker) + 0.8% surfactant Aerosol OT 75 (Cytec Industries)). For example, the third layer can be coated with a binder in an amount of about 1 gsm to about 10 gsm, about 1 gsm to about 8 gsm, or about 5 gsm. The first layer can be patterned on at least a portion of its outer surface. For example, and not by way of limitation, the nonwoven material can have a total basis weight of about 198 gsm.

[0091] In certain embodiments, the nonwoven material can have three layers. The first layer can include synthetic fibers such as eccentric bicomponent fibers (e.g., Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). For example, the first layer can include eccentric bicomponent fibers of about 50 gsm to about 60 gsm, about 10 gsm to about 50 gsm, or about 25 gsm. The second layer can include a blend of cellulosic fibers (e.g., GP 4723, Leaf River fully treated pulp) and synthetic fibers such as bicomponent fibers (e.g., Trevira PE / PET 70% core, 1.7 dtex, 6 mm). For example, the second layer can include cellulosic fibers of about 10 gsm to about 90 gsm, about 15 gsm to about 80 gsm, or about 71 gsm, and bicomponent fibers of about 1 gsm to about 50 gsm, about 5 gsm to about 35 gsm, or about 27 gsm. The third layer can comprise a blend of cellulosic fibers (e.g., eucalyptus pulp, Suzano, untreated) and synthetic fibers, such as bicomponent fibers (e.g., Trevira PE / PET 30% core, 1.5 dtex, 6 mm). For example, the third layer can comprise about 10 gsm to about 90 gsm, about 15 gsm to about 80 gsm, or about 62 gsm cellulosic fibers and about 1 gsm to about 50 gsm, about 5 gsm to about 35 gsm, or about 8 gsm bicomponent fibers. The outer surface of the third layer can be coated with a binder in the form of an emulsion (e.g., Vinnapas 192 (Wacker) + 0.8% surfactant Aerosol OT 75 (Cytec Industries)). For example, the outer surface of the third layer can be coated with a binder in an amount of about 1 gsm to about 10 gsm, about 1 gsm to about 8 gsm, or about 5 gsm. The third layer can be patterned on at least a portion of its outer surface.For example, and not by way of limitation, the nonwoven material can have a total basis weight of about 198 gsm.

[0092] In certain embodiments, the nonwoven material can include three layers and one or more additive layers. The first layer can include synthetic fibers, such as eccentric bicomponent fibers (e.g., Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). For example, the first layer can include eccentric bicomponent fibers of about 5 gsm to about 60 gsm, about 10 gsm to about 50 gsm, or about 25 gsm. The second layer can include a blend of cellulosic fibers (e.g., GP 4723, Leaf River fully treated pulp) and synthetic fibers, such as bicomponent fibers (e.g., Trevira PE / PET 70% core, 1.7 dtex, 6 mm). For example, the second layer can include about 10 gsm to about 90 gsm, about 15 gsm to about 80 gsm, or about 71 gsm cellulosic fibers and about 1 gsm to about 50 gsm, about 5 gsm to about 35 gsm, or about 27 gsm bicomponent fibers. One or more additive layers, such as a superabsorbent polymer (SAP) (e.g., Evonik Favor SXM 7900), can be disposed between the second and third layers. For example, the additive layer or layers can include about 5 gsm to about 30 gsm, about 15 gsm to about 25 gsm, or about 10 gsm superabsorbent polymer (SAP). The third layer can include a blend of cellulosic fibers (e.g., eucalyptus pulp, Suzano, untreated) and synthetic fibers, such as bicomponent fibers (e.g., Trevira PE / PET 30% core, 1.5 dtex, 6 mm). For example, the third layer can include cellulosic fibers of about 10 gsm to about 90 gsm, about 15 gsm to about 80 gsm, or about 62 gsm, and bicomponent fibers of about 1 gsm to about 50 gsm, about 5 gsm to about 35 gsm, or about 8 gsm. The outer surface of the third layer can be coated with a binder in the form of an emulsion (e.g., Vinnapas 192 (Wacker) + 0.8% surfactant Aerosol OT 75 (Cytec Industries)). For example, the outer surface of the third layer can be coated with a binder in an amount of about 1 gsm to about 10 gsm, about 1 gsm to about 8 gsm, or about 5 gsm. The first layer can have at least a portion of its outer surface patterned.For example, and not by way of limitation, the nonwoven material may have a total basis weight of about 208 gsm.

[0093] Method for producing nonwoven materials A variety of methods can be used to assemble the materials used in the practice of the presently disclosed subject matter to produce the material, including, but not limited to, traditional dry forming methods such as air-laying and carding, or other forming techniques such as spunlace or airlace. Preferably, the material is prepared by an airlaid process, which includes, but is not limited to, the use of one or more forming heads that deposit raw materials of different compositions in a selected order in a manufacturing process that produces a product having distinct layers. This allows for great versatility in the variety of products that can be produced.

[0094] In one embodiment, the material is prepared as a continuous airlaid web. Airlaid webs are typically prepared by disintegrating or defibering a sheet of cellulose pulp, typically with a hammer mill, to produce individualized fibers. Rather than a pulp sheet of virgin fibers, recycled airlaid edge trimmings, as well as off-spec transitional material resulting from grade changes and other airlaid manufacturing waste, can be fed to the hammer mill or other disintegrator. This ability to recycle manufacturing waste contributes to improved economics for the overall process. The individualized fibers, whether from virgin or recycled sources, are then pneumatically conveyed to the forming head of an airlaid web former. Several manufacturers produce airlaid web formers suitable for use in the presently disclosed subject matter, including Dan-Web Forming of Aarhus, Denmark; M&J Fibretech A / S of Horsens, Denmark; Rando Machine Corporation, Macedon, NY (described in U.S. Pat. No. 3,972,092); Margasa Textile Machinery of Cerdanyola del Valles, Spain; and DOA International of Wels, Austria. While these formers differ in the manner in which they open and air-transport the fibers onto the forming wire, they are all capable of producing webs of the presently disclosed subject matter. Dan-Web forming heads include rotating or oscillating perforated drums that help maintain fiber separation until the fibers are pulled by vacuum onto a foraminous forming conveyor or forming wire. In some embodiments, the forming wire, such as a Ribtech 84 (Albany International, Rochester, NH), can be patterned. A variety of patterns are suitable for use with the forming wire. For example, but not by way of limitation, the forming wire can have a pattern that includes grooves. In certain embodiments, the forming wire can be used as a forming dough. In an M&J machine, the forming head is essentially a rotary shaker above a screen.The rotary rocker may be equipped with a series or group of rotating propellers or fan blades. Other fibers, such as synthetic thermoplastic fibers, are opened, metered, and mixed in a fiber dosing system, such as a textile feeder supplied by Laroche SA of Cours-La Ville, France. In certain embodiments, such airlaid machines can be equipped with customized forming heads or heads capable of layer-individualized long fibers. From the textile feeder, the fibers are pneumatically conveyed to the forming head of the airlaid machine, where they are further mixed with comminuted cellulose pulp fibers from a hammer mill and deposited onto a continuously moving forming wire. If defined layers are desired, a separate forming head may be used for each type of fiber. Alternatively or additionally, one or more layers, if any, can be prefabricated before being combined with additional layers.

[0095] The airlaid web is transferred from the forming wire to a calender or other densification stage to densify the web, increase its strength, and control web thickness, if necessary. In one embodiment, the fibers of the web are then bonded by passing it through an oven set at a temperature high enough to fuse the included thermoplastic or other binder material. In a further embodiment, secondary bonding from the drying or curing of the latex spray or foam application occurs in the same oven. The oven may be a conventional ventilated oven, be operated as a convection oven, or achieve the necessary heating by infrared or even microwave irradiation. In certain embodiments, the airlaid web can be treated with additional additives before or after heat setting.

[0096] In some embodiments, one or more plasticizers, such as polyethylene glycol, can be applied to the cellulose sheet before it is comminuted with a hammer mill, or it can be applied by spraying onto the airlaid web either during the forming process or at the end of the airlaid line after the binder cure is complete. The silicone-based chemicals used can be sprayed onto the web as it is being formed or at the end of the airlaid line. Polyethylene glycol polymers are hydrophilic, unlike silicone-based chemicals, and can be more economical than silicones.

[0097] Intended Use and End Use The nonwoven material of the presently disclosed subject matter can be used in any application known in the art. For example, the nonwoven material can be used either alone or as a component in a variety of absorbent articles. In some embodiments, the nonwoven material can be used in absorbent articles that absorb and retain bodily fluids. Such absorbent articles include baby diapers, adult incontinence products, sanitary napkins, feminine hygiene products, personal care products, and the like.

[0098] In other aspects, the nonwoven material can be used alone or as a component in other consumer products. For example, the nonwoven material can be used in absorbent cleaning products such as wipes, sheets, towels, etc. [Example]

[0099] The following examples are merely illustrative of the subject matter of the present disclosure, and they should in no way be construed as limiting the scope of the subject matter.

[0100] Example 1 Low-flow nonwoven material This example provides absorbent nonwoven materials of the present disclosure and methods for manufacturing the same. Structures 1, 3, and 6 were used as control structures. Structures 2, 4, 5, and 7 were used as experimental structures. Such patterned nonwoven materials advantageously had low runoff properties.

[0101] Structure 1 was a two-layer nonwoven airlaid material formed using a pilot drum former and a flat former. The top layer comprised 26.34 gsm eccentric bicomponent fiber (Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). The bottom layer comprised a mixture of 6.28 gsm PET fiber (Trevira Type 245, 6.7 dtex, 3 mm) and 21.36 gsm cellulose fiber (GP 4723, Leaf River fully treated pulp) bonded with 6.02 gsm of polymeric binder in the form of an emulsion (Vinnapas 192, Wacker) containing 0.20 gsm of surfactant (Aerosol OT 75, Cytec Industries).

[0102] The composition of Structure 1 is shown in Table 1.

[0103] [Table 3]

[0104] Structure 2 was a two-layer nonwoven airlaid material formed using a pilot drum former and a patterned wire with grooves as the forming substrate. The top layer comprised 26.34 gsm eccentric bicomponent fiber (Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). The bottom layer comprised a mixture of 6.28 gsm PET fiber (Trevira Type 245, 6.7 dtex, 3 mm) and 21.36 gsm cellulose fiber (GP 4723, Leaf River fully treated pulp) bonded with 6.02 gsm of polymeric binder in the form of an emulsion (Vinnapas 192, Wacker) containing 0.20 gsm of surfactant (Aerosol OT 75, Cytec Industries).

[0105] The composition of Structure 2 is shown in Table 2 and Figure 1A, which schematically depicts the grooves incorporated into the structure.

[0106] [Table 4]

[0107] Structure 3 was a three-layer nonwoven airlaid material according to the presently disclosed subject matter formed using a pilot drum former and a flat forming fabric. The top layer comprised a 25 gsm eccentric bicomponent fiber (Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). The middle layer comprised a 27 gsm bicomponent fiber (Trevira PE / PET 70% core, 1.7 dtex, 6 mm) blended with a 71 gsm cellulosic fiber (GP 4723, Leaf River fully treated pulp). The bottom layer comprised a mixture of 62 gsm eucalyptus pulp (Suzano, untreated) and 8 gsm bicomponent fibre (Trevira PE / PET 30% core, 1.5 dtex, 6 mm) bonded with 5 gsm of polymeric binder in the form of an emulsion (Vinnapas 192 (Wacker) + 0.8% surfactant Aerosol OT 75 (Cytec Industries)).

[0108] Table 3 shows the composition of Structure 3.

[0109] [Table 5]

[0110] Structure 4 was a three-layer nonwoven airlaid material formed using a pilot drum former and a patterned wire with grooves as the forming substrate. Structure 4 was formed with all synthetic layers on the patterned wire. The top layer comprised a 25 gsm eccentric bicomponent fiber (Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). The middle layer comprised a blend of a 27 gsm bicomponent fiber (Trevira PE / PET 70% core, 1.7 dtex, 6 mm) and a 71 gsm cellulose fiber (GP 4723, Leaf River fully treated pulp). The bottom layer comprised a mixture of 62 gsm eucalyptus pulp (Suzano, untreated) and 8 gsm bicomponent fibre (Trevira PE / PET 30% core, 1.5 dtex, 6 mm) bonded with 5 gsm of polymeric binder in the form of an emulsion (Vinnapas 192 (Wacker) + 0.8% surfactant Aerosol OT 75 (Cytec Industries)).

[0111] The composition of Structure 4 is shown in Table 4 and Figure 1B, which schematically depicts the grooves incorporated into the structure.

[0112] [Table 6]

[0113] Structure 5 is a three-layer nonwoven airlaid material formed using a pilot drum former and a patterned wire as the forming fabric with grooves. This sample was formed using a eucalyptus layer on the patterned wire. The top layer contained a 25 gsm eccentric bicomponent fiber (Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). The middle layer contained a blend of a 27 gsm bicomponent fiber (Trevira PE / PET 70% core, 1.7 dtex, 6 mm) and a 71 gsm cellulose fiber (GP 4723, Leaf River fully treated pulp). The bottom layer comprised a mixture of 62 gsm eucalyptus pulp (Suzano, untreated) and 8 gsm bicomponent fibre (Trevira PE / PET 30% core, 1.5 dtex, 6 mm) bonded with 5 gsm of polymeric binder in the form of an emulsion (Vinnapas 192 (Wacker) + 0.8% surfactant Aerosol OT 75 (Cytec Industries)).

[0114] Table 5 and Figure IC show the composition of Structure 5. Figure 1C depicts a schematic of the grooves incorporated into the structure.

[0115] [Table 7]

[0116] Structure 6 is a three-layer nonwoven airlaid material with superabsorbent polymer (SAP) formed using a pilot drum former and flat forming fabric. The top layer contained 25 gsm eccentric bicomponent fiber (Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). The middle layer contained a blend of 25 gsm bicomponent fiber (Trevira PE / PET 70% core, 1.7 dtex, 6 mm) and 65 gsm cellulose fiber (GP 4723, Leaf River fully treated pulp). A layer of 10 gsm superabsorbent polymer (Evonik Favor SXM 7900) was added between the bottom and middle layers using a Christy feeder. The bottom layer comprised a mixture of 62 gsm eucalyptus pulp (Suzano, untreated) and 8 gsm bicomponent fibre (Trevira, PE / PET 30% core, 1.5 dtex 6 mm) bonded with 5 gsm of polymeric binder in the form of an emulsion (Vinnapas 192 (Wacker) + 0.8% surfactant Aerosol OT 75 (Cytec Industries)).

[0117] Table 6 shows the composition of Structure 6.

[0118] [Table 8]

[0119] Structure 7 was a three-layer nonwoven airlaid material with superabsorbent polymer (SAP) formed using a pilot drum former and a patterned wire as the forming fabric with grooves. A synthetic layer was used on the patterned wire to form Structure 7. The top layer contained 25 gsm eccentric bicomponent fiber (Trevira Type 255, 6.7 dtex, 6 mm, PE / PET). The middle layer contained a blend of 25 gsm bicomponent fiber (Trevira PE / PET 70% core, 1.7 dtex, 6 mm) and 65 gsm cellulose fiber (GP 4723, Leaf River fully treated pulp). A layer of 10 gsm superabsorbent polymer (Evonik Favor SXM 7900) was added between the bottom and middle layers using a Christy feeder. The bottom layer comprised a mixture of 62 gsm eucalyptus pulp (Suzano, untreated) and 8 gsm bicomponent fibre (Trevira PE / PET 30% core, 1.5 dtex, 6 mm) bonded with 5 gsm of polymeric binder in the form of an emulsion (Vinnapas 192 (Wacker) + 0.8% surfactant Aerosol OT 75 (Cytec Industries)).

[0120] The composition of Structure 7 is shown in Table 7 and Figure ID, which schematically depicts the grooves incorporated into the structure.

[0121] [Table 9]

[0122] Example 2 Runoff test (Structure 1-7) This example provides runoff testing of the absorbent nonwoven material of Example 1. Constructions 1, 3 and 6 were used as control constructions. Constructions 2, 4, 5 and 7 were used as experimental constructions.

[0123] Manufacturers of hygiene products use various test methods to measure the effectiveness of their products. One such test is the runoff test. The runoff test involves placing a sample of absorbent material on a flat surface at a 30-degree angle and discharging a sample containing 5 mL of synthetic blood at a rate of 38 mL / min. The less blood that flows out of the sample, the better the performance, and the less likely there is to be leakage when the test material is used as a component of a finished hygiene absorbent product.

[0124] Spill Test Flux was measured on 8" x 2.5" samples for constructs 1-7. The samples (either compressed at 4 bar pressure or not compressed at all prior to testing) were lined with the eccentric bicomponent fiber layer as the top side of the construct using the bottom edge of a 30-degree angled Plexiglas plate. The sample was then taped to the plate. Five mL of synthetic blood (Johnson, Moen and Co. Inc.; Lot#=528181; received May 2018; Product Identification = ASTM F1670 synthetic blood, with a viscosity of 5.56 cPs and a surface tension of 40-44 dynes / cm; Chemicals = Acrysol GIll: polyacrylate ammonium polymer, Twitchell 6808 surfactant, Direct Red Azo Dye 081, and HPLC-distilled water) was pumped through the sample for 7.9 seconds. The pump delivered the synthetic blood at a flow rate of 38 mL / min. The location of the discharge was 5 cm horizontally from the bottom of the sample. The tubing carrying the synthetic blood was 1 cm above the sample. The synthetic blood was not readily absorbed by the sample and spilled onto a plastic weighing boat, which was weighed to give the spilled mass. The percent spillage was then calculated.

[0125] Structures 1 and 2 Structures 1 and 2 were tested for bleed-through. Structure 1 was the control sample. A bleed-through test was performed on Structure 1 cut lengthwise. Then, several pieces of Structure 1 cut crosswise were bleed-through tested. Similarly, a bleed-through test was performed on Structure 2, which was cut so that lines ran along the length of the sample. These lines are designated as "length lines" in Figure 2. A bleed-through test was performed on Structure 2, which was cut so that lines ran side-to-side or across the width of the sample. These lines are designated as "width lines" in Figure 2. Hereafter, the four previous tests were repeated on the samples after compressing them using a pressure of 4 bar. The term "lines" is used herein to describe the texture pattern observed from the bottom side of Structure 2, which appears to be a visible line. Lines created by areas of lower basis weight in Structure 2 represent valleys, while lines created by areas of higher basis weight in Structure 2 represent peaks.

[0126] FIG. 2 shows the test results for Samples 1 and 2.

[0127] The uncompressed structure of Structure 2 (shown in Figure 1B) is significantly better at preventing runoff than the uncompressed structure of Structure 1 (shown in Figure 1A). This unexpected improvement in runoff performance is achieved when the textured surface is positioned opposite the liquid collection surface, regardless of the orientation of the pattern. The role that the textured surface plays in runoff is further demonstrated for the 4 bar compressed structures. 4 bar compressed Structure 1, fabricated with a flat wire and cut transversely, has significantly higher runoff than 4 bar compressed Structure 2, fabricated with a patterned wire and cut transversely with lines running side to side or across the width of the sample.

[0128] Structure 3-5 Structures 3-5 were tested for flow-out. Structure 3 was the control sample. Flow-out tests were performed on Structure 3, which was cut in the longitudinal direction. Flow-out tests were then performed on several Structures 4 and 5, which were cut in the longitudinal and transverse directions. The longitudinal samples are designated as having a "width line," where a line runs the full width of the sample. The transverse samples are designated as having a "length line," where a line runs the full length of the sample. The five previous tests were then repeated on the samples after compression at 4 bar pressure.

[0129] Figure 3 shows the test results for Sample 3-5.

[0130] All uncompressed S800 samples using patterned wire showed improved runoff performance compared to samples made with flat formed wire. The runoff of the compressed samples was all the same or improved over the control. This data also shows that runoff can be improved using patterns on the top and bottom of the structure.

[0131] Structure 6-7 Structures 6-7 were tested for bleed-out. Structure 6 was the control sample. The bleed-out test was performed on Structure 6, which was cut in the longitudinal direction. Then, bleed-out tests were performed on several Structures 7, which were cut in the longitudinal and transverse directions. The longitudinal samples are designated as having a "width line," where a line runs the full width of the sample. The transverse samples are designated as having a "length line," where a line runs the full length of the sample. The three previous tests were then repeated on the samples after compression at 4 bar pressure.

[0132] Figure 4 shows the test results for Samples 6-7.

[0133] Both the compressed and uncompressed Structure 7 samples with width lines performed better to runoff than the control Structure 6. The compressed and uncompressed Structure 7 samples with length lines performed worse than the Structure 6 control. As shown in Figure 4, adding superabsorbent polymer (SAP) to the structures improved the performance of all compressed samples compared to the uncompressed samples.

[0134] In addition to the various embodiments described and claimed, the presently disclosed subject matter is directed to other embodiments having other combinations of the features disclosed and claimed herein. Accordingly, particular features presented herein can be combined with each other in other manners within the scope of the presently disclosed subject matter such that the presently disclosed subject matter includes any suitable combination of the features disclosed herein. The foregoing descriptions of specific embodiments of the presently disclosed subject matter have been presented for purposes of illustration and description and are not intended to be exhaustive or to limit the presently disclosed subject matter to those disclosed embodiments.

[0135] It will be apparent to those skilled in the art that various modifications and variations can be made in the systems and methods of the presently disclosed subject matter without departing from the spirit or scope of the presently disclosed subject matter. Thus, it is intended that the presently disclosed subject matter cover modifications and variations that come within the scope of the appended claims and their equivalents.

[0136] Various patents and patent applications are cited herein, the contents of which are incorporated herein by reference in their entireties.

Claims

1. 1. An airlaid nonwoven material comprising: a first layer comprising bicomponent fibers; and a second layer disposed adjacent to the first layer, the second layer comprising cellulosic fibers and bicomponent fibers; Including, the second layer is bonded to at least a portion of its outer surface with a bonding agent; At least a portion of the second layer is patterned; An airlaid nonwoven material, wherein the nonwoven material has a percent runoff of less than about 5%.

2. 10. The airlaid nonwoven material of claim 1, wherein the patterning of the second layer comprises alternating ridges and valleys, the ridges having a higher basis weight than the valleys.

3. 3. The airlaid nonwoven material of claim 2, wherein the ridges are from about 2 mm to about 4 mm wide and the valleys are from about 1 mm to about 2.5 mm wide.

4. 10. An absorbent article comprising the airlaid nonwoven material of claim 1.

5. 1. An airlaid nonwoven material comprising: a first layer comprising bicomponent fibers; a second layer disposed adjacent to the first layer, the second layer comprising cellulosic fibers and bicomponent fibers; and a third layer disposed adjacent to the second layer, the third layer comprising cellulosic fibers and bicomponent fibers; Including, the third layer is bonded to at least a portion of its outer surface with a bonding agent; At least a portion of at least one of the first and third layers is patterned; An airlaid nonwoven material, wherein the nonwoven material has a percent runoff of less than about 5%.

6. 6. The airlaid nonwoven material of claim 5, wherein the patterning of at least one of the first and third layers comprises alternating ridges and valleys, the ridges having a higher basis weight than the valleys.

7. 7. The airlaid nonwoven material of claim 6, wherein the ridges are from about 2 mm to about 4 mm wide and the valleys are from about 1 mm to about 2.5 mm wide.

8. 10. An absorbent article comprising the airlaid nonwoven material of claim 5.

9. 1. An airlaid nonwoven material comprising: a first layer comprising bicomponent fibers; a second layer disposed adjacent to the first layer, the second layer comprising cellulosic fibers and bicomponent fibers; a third layer disposed adjacent to the second layer, the third layer comprising eucalyptus fibers and bicomponent fibers; and a layer of superabsorbent polymer disposed between the second and third layers; Including, the third layer is bonded to at least a portion of its outer surface with a bonding agent; At least a portion of the first layer is patterned; An airlaid nonwoven material, wherein the nonwoven material has a percent runoff of less than about 5%.

10. 10. The airlaid nonwoven material of claim 9, wherein the patterning of the first layer comprises alternating ridges and valleys, the ridges having a higher basis weight than the valleys.

11. 11. The airlaid nonwoven material of claim 10, wherein the ridges are from about 2 mm to about 4 mm wide and the valleys are from about 1 mm to about 2.5 mm wide.

12. 10. An absorbent article comprising the airlaid nonwoven material of claim 9.

13. 1. An airlaid nonwoven material comprising: a first layer comprising synthetic fibers; and a second layer disposed adjacent to the first layer, the second layer comprising cellulosic fibers and synthetic fibers; the nonwoven material is patterned over at least a portion of at least one surface; An airlaid nonwoven material, wherein the nonwoven material has a percent runoff of less than about 5%.

14. 14. The airlaid nonwoven material of claim 13, wherein the nonwoven material has a percent runoff of less than about 1%.

15. 14. The airlaid nonwoven material of claim 13, further comprising a third layer disposed adjacent to the second layer, the third layer comprising cellulosic fibers and synthetic fibers.

16. 16. The airlaid nonwoven material of claim 15, further comprising a layer of superabsorbent polymer disposed between the second and third layers.

17. 14. The airlaid nonwoven material of claim 13, wherein the second layer is bonded to at least a portion of its outer surface with a binder.

18. 16. The airlaid nonwoven material of claim 15, wherein the third layer is bonded to at least a portion of its outer surface with a binder.

19. 16. The airlaid nonwoven material of claim 15, wherein the cellulosic fibers of the third layer comprise eucalyptus fibers.

20. 14. The airlaid nonwoven material of claim 13, wherein the synthetic fibers of the first and second layers comprise bicomponent fibers.

21. 14. An absorbent article comprising the airlaid nonwoven material of claim 13.

22. 1. An airlaid nonwoven material comprising: a first layer comprising synthetic fibers; a second layer disposed adjacent to the first layer, the second layer comprising cellulosic and synthetic fibers; and a third layer disposed adjacent to the second layer, the third layer comprising cellulosic and synthetic fibers; Including, the nonwoven material is patterned over at least a portion of at least one surface; An airlaid nonwoven material, wherein the nonwoven material has a percent runoff of less than about 5%.

23. 23. The airlaid material of claim 22, wherein the nonwoven material has a percent bleed-through of less than about 1%.

24. 23. The nonwoven material of claim 22, further comprising a layer of superabsorbent polymer disposed between the second and third layers.

25. 23. The nonwoven material of claim 22, wherein the third layer is bonded to at least a portion of its outer surface with a binder.

26. 23. The nonwoven material of claim 22, wherein the cellulosic fibers of the third layer comprise eucalyptus fibers.

27. 23. An absorbent article comprising the nonwoven material of claim 22.

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