Flexible absorbent coform nonwoven web

Abstract

Soft and strong nonwoven web materials and methods of forming are described. In one embodiment, a nonwoven web can comprise: first and second outer regions of meltblown polymeric fibers and absorbent fibers, the meltblown fibers formed from a first polymeric component and a second polymeric component, wherein the second polymeric component comprises greater than 0 wt% and less than or equal to 20 wt% of the total polymeric material content of the meltblown polymeric fibers; and a central region disposed between the first and second outer regions and comprising meltblown polymeric fibers and absorbent fibers, the meltblown fibers being different from the meltblown polymeric fibers of the first and second outer regions and not comprising the second polymeric component.

Description

Background Technology

[0001] Nonwoven webs, sometimes called co-formed webs, are composites of meltblown thermoplastic fiber matrix and secondary fiber materials. They have been used as absorbent layers in a variety of applications, including absorbent articles, absorbent dry wipes, wet wipes, and mops. Many traditional co-formed webs utilize meltblown thermoplastic fiber materials formed from polypropylene and / or polyethylene homopolymers. While the use of polyethylene homopolymers can increase the softness of co-formed webs, it can also reduce their strength. Continuous improvement in both the softness and strength of co-formed webs is desired. Summary of the Invention

[0002] In a first embodiment, the nonwoven web material may comprise: a first outer region comprising: a first meltblown polymer fiber, the first meltblown polymer fiber comprising a first polymer component and a second polymer component, and absorbent fibers, wherein the content of the second polymer component of the first meltblown polymer fiber is greater than 0% by weight and less than or equal to 20% by weight of the total polymer content of the first meltblown polymer fiber; a second outer region comprising: a second meltblown polymer fiber, the second meltblown polymer fiber comprising a first polymer component and a second polymer component, and absorbent fibers, wherein the content of the second polymer component of the second meltblown polymer fiber is greater than 0% by weight and less than or equal to 20% by weight of the total polymer content of the second meltblown polymer fiber; and a central region disposed between the first outer region and the second outer region, the central region comprising: a third meltblown polymer fiber, the third meltblown polymer fiber being different from the first meltblown polymer fiber and the second meltblown polymer fiber, and not comprising the second polymer component, and absorbent fibers.

[0003] In another embodiment, the layered co-formed nonwoven web material having a certain thickness may include: a first outer region comprising a combination of meltblown polymer fibers and absorbent fibers; a second outer region comprising a combination of meltblown polymer fibers and absorbent fibers; and a central region disposed between the first outer region and the second outer region, the central region comprising a combination of meltblown polymer fibers and absorbent fibers, wherein at least some of the meltblown polymer fibers comprise bicomponent meltblown polymer fibers, and at least some of the meltblown polymer fibers comprise monocomponent meltblown polymer fibers, the bicomponent meltblown polymer fibers extending through a thickness less than the entire thickness of the layered co-formed nonwoven web.

[0004] In another embodiment, the layered co-formed web material has a certain total basis weight and may include: a first co-formed outer region comprising: meltblown polymer fibers, the meltblown polymer fibers comprising bicomponent meltblown polymer fibers formed from a first polymer component and a second polymer component, the second polymer component being present in an amount greater than 0% and less than or equal to 3% of the total basis weight of the layered co-formed web material, and accounting for less than or equal to 40% of the total polymer content of the bicomponent meltblown polymer fibers in the first co-formed outer region, and absorbent fibers; and a second co-formed outer region comprising: meltblown polymer fibers, the meltblown polymer fibers comprising the first polymer component... The material comprises: bicomponent meltblown polymer fibers formed from a second polymer component, wherein the second polymer component is present in an amount greater than 0% and less than or equal to 3% of the total basis weight of the layered co-formed web material, and accounts for less than or equal to 40% of the total polymer content of the bicomponent meltblown polymer fibers in the second co-formed outer region; and absorbent fibers; and a central co-formed region disposed between the first co-formed outer region and the second co-formed outer region, wherein the basis weight of the central co-formed region is greater than or equal to 40% and less than or equal to 60% of the total basis weight of the layered co-formed web material, and the central co-formed region comprises: meltblown polymer fibers, wherein the meltblown polymer fibers comprise monocomponent meltblown polymer fibers; and absorbent fibers.

[0005] Other features and aspects of the invention are described in more detail below. Attached Figure Description

[0006] The complete and feasible disclosure of the invention (including its best mode) for those skilled in the art is set forth in more detail in the remainder of the specification with reference to the accompanying drawings, in which:

[0007] Figure 1 This is a schematic diagram of an exemplary cross-section of a nonwoven web according to various aspects of this disclosure;

[0008] Figure 2 This is a schematic diagram of one embodiment of a method for forming the nonwoven web of this disclosure;

[0009] Figure 3 This is a schematic diagram of an alternative embodiment of the method for forming the nonwoven web of this disclosure;

[0010] Figure 4 Is it like this? Figure 2 and Figure 3 Examples of certain features of the apparatus for forming nonwoven webs are shown;

[0011] Figure 5A and Figure 5BThese are schematic cross-sectional configurations of exemplary fibers that can be used to form nonwoven webs according to this disclosure; and

[0012] Figure 6 These are charts illustrating the strength and softness values ​​of various nonwoven webs according to various aspects of this disclosure;

[0013] Figure 7 and Figure 8 A cup pressing test system 1100 including a cup forming assembly 1102 is shown.

[0014] The repeated use of reference numerals in this specification and drawings is intended to represent the same or similar features or elements of the invention. Detailed Implementation

[0015] Reference will now be made in detail to various embodiments of the invention, one or more of which are illustrated below. Each example is provided by way of explanation rather than limitation. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made to the invention without departing from the scope or spirit thereof. For example, a feature illustrated or described as part of one embodiment may be used in another embodiment to produce another embodiment. Therefore, the invention is intended to cover such modifications and variations.

[0016] As used herein, the term "nonwoven fabric or web" refers to a web having a structure of individual fibers or threads arranged in layers but not in a regular or identifiable manner (as in knitted fabrics). It also includes foams and films that have been fibrillated, opened, or otherwise treated to impart fabric-like properties. Nonwoven fabrics or webs have been formed by numerous processes, such as meltblown, spunbond, hydroentangled, and bonded carding web processes. The basis weight of nonwoven fabrics is typically expressed in ounces per square yard (osy) or grams per square meter (gsm), while fiber diameter is typically expressed in µm.

[0017] As used herein, the term "microfiber" refers to a small-diameter fiber with an average diameter of no more than about 75 μm, for example, an average diameter of about 0.5 μm to about 50 μm, or more specifically, an average diameter of about 2 μm to about 40 μm. Another common expression for fiber diameter is denier, defined as the weight in grams per 9,000 meters of fiber, and can be calculated by multiplying the fiber diameter in µm squared by the density in grams per cc by 0.00707. Lower deniers indicate finer fibers, and higher deniers indicate coarser or heavier fibers. For example, a given 15 µm polypropylene fiber diameter can be converted to denier by squaring the diameter and multiplying the result by 0.89 g / cc and 0.00707. Therefore, the denier number of a 15 µm polypropylene fiber is approximately 1.42 (152 × 0.89 × 0.00707 = 1.415). Outside the United States, the unit of measurement is more commonly the "tex," which is defined as the number of grams of fiber per kilometer. A tex can be calculated as denier / 9.

[0018] As used herein, the term "meltblown fiber material" refers to fibers formed by extruding molten thermoplastic material as molten wires or filaments through multiple typically circular, fine-die capillaries into a converging high-speed gas stream (e.g., an airflow). This high-speed gas stream thins the molten thermoplastic filaments to reduce their diameter, which may be the diameter of a microfiber. The meltblown fiber material is then carried by the high-speed airflow and deposited onto a collecting surface to form a web composed of randomly dispersed meltblown fiber material. The meltblown fiber material is a microfiber that may be continuous or discontinuous and typically has an average diameter of less than 10 μm.

[0019] As used herein, the term "polymer flux" refers to the amount of polymer passing through a die and is specified in pounds of polymer melt per hour per inch of die width (pih) or grams of polymer melt per minute per orifice (ghm). To calculate the flux in pih from ghm units, multiply ghm by the number of fiber emission orifices per inch of fiber forming die (orifices / inch) and then divide by 7.56.

[0020] This disclosure relates to nonwoven webs (referred to herein as co-formed webs) combining thermoplastic fiber materials and secondary fiber materials, achieving a superior combination of softness and strength compared to previous co-formed webs. To form such co-formed webs, meltblown fiber material is mixed with one or more secondary fiber materials and / or granules. The mixture is collected in the form of a fiber nonwoven web, which, according to some embodiments, can be bonded or treated to provide a coherent nonwoven material that utilizes at least some properties of each component. These mixtures are referred to as “co-formed” materials because they are formed by combining two or more materials into a single structure in a forming step. Further details regarding such co-formed materials and processes are described herein.

[0021] The co-formed web of this disclosure comprises a first meltblown fiber (referred to herein as a "bicomponent fiber," or also a multicomponent fiber) containing a first polymer component and a second meltblown fiber (referred herein as a "homogeneous fiber," or also a single-component fiber) containing a first homopolymer. Although the term "bicomponent fiber" is used herein, it should not be construed as limiting such fiber to containing only two polymer components. Rather, such a bicomponent fiber as used herein contains at least two polymer components, but may contain additional polymer components. (See reference...) Figure 2 and Figure 3 Methods 200 and 300, as described, allow bicomponent meltblown fibers and homogeneous meltblown fibers to be combined with secondary fiber materials in a layered manner to produce a layered co-shaped structure—a schematic cross-section of which can be referenced. Figure 1 See.

[0022] Figure 1 An example cross-section shows a nonwoven web 100 having a first outer region 102, a second outer region 104, and a central region 106. The first outer region 102 and the second outer region 104 are each free of secondary fiber material (…). Figure 1 In this embodiment, fiber 101 is formed together with bicomponent meltblown fiber 103. The central region 106 is formed together with a secondary fiber material (e.g., fiber 101) and homogeneous meltblown fiber 105. Figure 1 In the depiction, fiber 101 is shown as a straight, flat-end line, bicomponent meltblown fiber 103 is shown as a thicker curve, and homogeneous meltblown fiber 105 is shown as a thinner curve. It should be understood that these depictions are for illustrative purposes only. For example, bicomponent meltblown fiber 103 and homogeneous meltblown fiber 105 can actually be the same size. Furthermore, in the formed web, bicomponent meltblown fiber 103 and homogeneous meltblown fiber 105 can be arranged in a more... Figure 1 The fibers shown are longer and more continuous. Furthermore, there may be cross-linking or connections between some of the bicomponent meltblown fibers 103 and the homogeneous meltblown fibers 105. However... Figure 1 This should be understood as illustrating the general concept that the outer regions 102, 104 contain a substantially higher concentration of bicomponent meltblown fibers 103, while the central region 106 contains a substantially higher concentration of homogeneous meltblown fibers 105. Although such a specific concentration may be difficult to measure within the formed web 100, it can be collected from the web 100 forming process.

[0023] exist Figure 1 In a particular embodiment of the nonwoven web 100, it may be particularly advantageous that the total basis weight of the web 100 is from about 20 gsm to about 150 gsm. In a more specific embodiment, the total basis weight of the web 100 may be from about 50 gsm to about 125 gsm, or from about 50 gsm to about 80 gsm. In such an embodiment, the central region 106 may preferably account for 20% to 80% of the total basis weight of the web 100, or in other embodiments, from about 30% to about 60%. Thus, the first outer region 102 and the second outer region 104 may account for about 80% to about 20%, or about 70% to about 40% of the total basis weight of the web 100.

[0024] In some embodiments, the first outer region 102 and the second outer region 104 may have equal basis weights. For example, if the total basis weight of the web 100 is 100 gsm, and the combined basis weight of the first outer region 102 and the second outer region 104 is 50% of the total basis weight, then the basis weight of each of the first outer region 102 and the second outer region 104 will be 25 gsm. In alternative embodiments, the basis weights of the first outer region 102 and the second outer region 104 may be different. In these embodiments, the basis weight of either the first outer region 102 or the second outer region 104 may be from about 35% to about 65% of the combined basis weight of the first outer region 102 and the second outer region 104. As an illustrative example, if the basis weight of the nonwoven web 100 is 100 gsm, the combined basis weight of the first outer region 102 and the second outer region 104 is 50% of the total basis weight, and the basis weight of the first outer region 102 is 65% of the combined basis weight of the first outer region 102 and the second outer region 104, then the basis weight of the first outer region 102 will be 65% of 50 gsm, i.e., 32.5 gsm. In this example, the basis weight of the second outer region 104 will be 17.5 gsm.

[0025] In each of regions 102, 104, and 106, the basis weight of the components of the web 100 may be particularly important for driving the desired softness and strength properties of the web 100. For example, the central region 106 may advantageously consist of secondary fiber materials such as fiber 101 and homogeneous meltblown fiber 105. Within the central region 106, fiber 101 may be arranged with a basis weight between about 55% and about 85% of the total basis weight of the central region 106. Thus, homogeneous meltblown fiber 105 may be arranged with a basis weight between about 15% and about 45% of the total basis weight of the central region 106. In a more specific embodiment, fiber 101 may be arranged with a basis weight between about 60% and about 75% of the total basis weight of the central region 106. Then, homogeneous meltblown fiber 105 will be arranged with a basis weight between about 25% and about 50% of the total basis weight of the central region 106.

[0026] As described above, the first outer region 102 and the second outer region 104 may advantageously consist of a secondary fiber material (e.g., fiber 101) and bicomponent meltblown fibers 103. Each of the first outer region 102 and the second outer region 104 may have fibers 101 arranged with a basis weight between about 50% and about 80% of the total basis weight of the respective regions 102 and 104. More specifically, the basis weight of the fibers 101 in the first outer region 102 may be about 55% to about 70% of the total basis weight of the first outer region 102. Similarly, the basis weight of the fibers 101 in the second outer region 104 may be about 50% to about 80%, or about 55% to about 70%, of the total basis weight of the second outer region 104. Thus, the first outer region 102 and the second outer region 104 may each have bicomponent meltblown fibers 103 with a basis weight of about 20% to about 50% of the total basis weight of the first outer region 102 and the second outer region 104, respectively. In a more specific embodiment, the first outer region 102 and the second outer region 104 may each have bicomponent meltblown fibers 103 arranged at a basis weight of about 30% to about 45% of the total basis weight of their respective regions 102, 104.

[0027] In at least some of these examples, the first outer region 102 and the second outer region 104 may have meltblown fibers, such as bicomponent meltblown fibers 103, arranged at a percentage greater than that of the meltblown fibers in the central region 106 relative to the weight of the first outer region 102 and the second outer region 104, for example, homogeneous meltblown fibers 105 arranged at a percentage of the weight of the central region 106. For example, the first outer region 102 and the second outer region 104 may have meltblown fibers arranged at a weight greater than or equal to about 25% of the total weight of the first outer region 102 and the second outer region 104, while the central region has meltblown fibers arranged at a weight less than about 20% of the weight of the central region 106. In another example, the first outer region 102 and the second outer region 104 may have meltblown fibers arranged at a basis weight greater than or equal to about 30% of the total basis weight of the first outer region 102 and the second outer region 104, while the central region has meltblown fibers arranged at a basis weight less than about 30% of the basis weight of the central region 106.

[0028] Strength and softness are largely driven by the amount and type of polymer used to form homogeneous meltblown fibers and bicomponent meltblown fibers. In embodiments according to this disclosure, a first polymer component having properties that provide strength to the web 100 can be utilized. For example, the first polymer component may have properties that form strong meltblown fibers that provide strength to the web 100. Homogeneous meltblown fibers 105 can be formed using the first polymer component. In some embodiments, the first polymer component can be used as a component of bicomponent meltblown fibers 103.

[0029] A second polymer component with properties that provide softness to the web 100 can be utilized. For example, the second polymer component may have properties that provide a soft feel, thus the meltblown fibers formed from the second polymer component can provide a soft feel to the web 100. In some embodiments according to this disclosure, the second polymer component can be used as a component of the bicomponent meltblown fiber 103. Therefore, in some embodiments, the first polymer component and the second polymer component can be separate components of the bicomponent meltblown fiber 103. In other embodiments, the first polymer component can be used to form homogeneous meltblown fibers 105, the second polymer component can be used as a component of the bicomponent meltblown fiber 103, and a third polymer component can be used as another component of the bicomponent meltblown fiber 103. In any of these various embodiments, typically the first polymer component or the third polymer component will be used to provide strength to the bicomponent meltblown fiber 103, while the second polymer component provides softness to the bicomponent meltblown fiber 103.

[0030] Therefore, the relative amounts of the first polymer component and the second polymer component, or the first polymer component, the second polymer component, and the third polymer component, are likely to be the main drivers of the overall strength and softness of the web 100. It has been found that a beneficial amount of the polymer component providing softness to the web 100 (e.g., the second component in the embodiments described above) is 0.1% to 5% by weight of the total weight of the nonwoven web 100. More specific embodiments may preferably have a polymer component providing softness to the web 100 of 0.25% to 4% by weight, or 0.4% to 3% by weight, or 0.6% to 2.5% by weight of the total weight of the nonwoven web 100. One or more polymer components providing strength to the nonwoven web 100, such as the first polymer component or a combination of the first and third polymer components, may preferably be present in a combined amount of 20% to 40% by weight of the total weight of the nonwoven web 100. In a more specific embodiment, it may be preferred that the polymer component providing strength to the nonwoven web is present in an amount of 23% to 37% by weight, or 25% to 35% by weight, or 27% to 33% by weight of the total weight of the nonwoven web 100.

[0031] In at least some embodiments of this disclosure, it may be particularly preferred to ensure that one or more polymeric components (referred to herein as the first polymeric component or the first and third polymeric components) providing strength to the web 100 and a polymeric component (referred herein as the second polymeric component) providing flexibility to the web 100 are arranged in a specific manner within the bicomponent meltblown fiber 103. For example, it is preferred that the first or third polymeric component is arranged as an internal component of the bicomponent meltblown fiber 103, and the second polymeric component is arranged as an external component of the bicomponent meltblown fiber 103. In certain embodiments of this disclosure, it is preferred that the second polymeric component substantially surrounds and covers the first or third polymeric component of the bicomponent meltblown fiber 103—for example, wherein the bicomponent meltblown fiber 103 has, for example, a shape such that... Figure 5A and Figure 5B The core-sheath type or cat's-eye type cross-sectional structure shown has a second polymer component 301 surrounding a first (or third) polymer component 303.

[0032] The bicomponent meltblown fiber 103 can be formed from various shaped cross sections to achieve this configuration. For example, the bicomponent meltblown fiber 103 can be formed with a core-sheath type or cat's-eye type shaped cross section or other similar shaped cross sections, wherein the second polymer component surrounds the first polymer component or the third polymer component—such as an island-shaped cross section. However, it should be understood that shaped cross sections without the second polymer component surrounding the first polymer component or the third polymer component are still within the scope of the bicomponent meltblown fiber 103 considered in this disclosure. For example, bicomponent meltblown fiber 103 with an ABA shaped cross section has been found to perform particularly well, where, during the stretching / thinning of the fiber as part of the meltblowing process, component A (e.g., the second polymer component) expands and wraps around component B (e.g., the first polymer component or the third polymer component). In this way, shaped cross sections without the second polymer component surrounding the first polymer component can produce fibers with a cross-sectional configuration in which the second polymer substantially surrounds and covers the first polymer or the third polymer. It has been found that other shaped cross sections (such as the AB cross section) also produce the beneficial performance results of the web 100 of this disclosure, but not to the extent of other meltblown fiber shaped cross sections, which allow the second polymer component to more fully surround and cover the first polymer component or the third polymer component, even when the total amount of component A is low.

[0033] As used herein, the forming cross-section is the cross-sectional structure of the polymer component within the channel leading to the die tip orifice of the meltblown die 216. In the grant Haynes et al. The key considerations for forming such bicomponent meltblown fibers are described in U.S. Patent No. 6,474,967, and in the granted patent... Pike Different fiber cross sections and techniques for forming such bicomponent meltblown fiber cross sections are described in U.S. Patent No. 5,935,883, which are incorporated herein by reference in their entirety. For example, U.S. Patent No. 6,474,967 describes an example mold and baffle that can be used to form bicomponent meltblown fibers, and further describes that it may be particularly important that the viscosity of the polymer components of the bicomponent meltblown fiber 103 is sufficiently similar.

[0034] Other methods for forming multicomponent fibers are granted Taniguchi et al. U.S. Patent No. 4,789,592, granted Strack et al. U.S. Patent No. 5,336,552, granted Kaneko et al. U.S. Patent No. 5,108,820, granted Kruege et al. U.S. Patent No. 4,795,668, granted Pike et al. U.S. Patent No. 5,382,400, granted Strack et al. U.S. Patent No. 5,336,552 and granted Marmon et al. The invention is described in U.S. Patent No. 6,200,669, which is incorporated herein by reference in its entirety for all purposes. Multicomponent fibers with various irregular cross-sectional shapes that may be useful according to aspects of this disclosure are granted in [the context of] [the invention / approval / etc.]. Hogle et al. U.S. Patent No. 5,277,976, granted Hills U.S. Patent No. 5,162,074, granted Hills U.S. Patent No. 5,466,410, granted Largman et al. U.S. Patent No. 5,069,970 and granted Largman et al. The patents described in U.S. Patent No. 5,057,368 are incorporated herein by reference in their entirety for all purposes.

[0035] To achieve the optimal combination of strength and flexibility in the web 100, it has been found that not only should the first polymer group (or the first and third polymer components) and the second polymer component be arranged in the preferred amounts as described above, but the bicomponent meltblown fiber 103 should also have a specific ratio of the first polymer group or the third polymer component and the second polymer component. In these embodiments, the preferred amount of the second polymer component is from about 1.5% to about 25% by weight of the bicomponent meltblown fiber 103. In a more specific embodiment, the bicomponent meltblown fiber 103 comprises from about 1.5% to about 20%, or from about 1.5% to about 15%, or from about 1.5% to about 10% by weight of the bicomponent meltblown fiber 103. It has been surprisingly discovered that bicomponent meltblown fibers 103 can be produced where the second polymer component constitutes as little as 10% by weight, or even less such as 1.5% by weight, of the bicomponent meltblown fiber 103, wherein the second polymer component still provides relatively large coverage around the first or third polymer component—for example, forming a core-sheath cross-sectional structure, whether formed by a core-sheath shaped cross-section or such a core-sheath shaped cross-section is produced by a different shaped cross-section (such as an ABA shaped cross-section as an example). In this way, bicomponent meltblown fibers 103 can be utilized which have a beneficial softness—the second polymer component substantially covers and surrounds the first (or third) polymer component—and are as strong as possible, with the first or third polymer component forming as many bicomponent meltblown fibers 103 as possible.

[0036] homogeneous fibers

[0037] The homogeneous meltblown fiber 105 disclosed herein is preferably a meltblown fiber with a diameter ranging from about 1 µm to 25 µm, or more particularly from about 2 µm to about 20 µm, or from about 2 µm to about 10 µm, or from about 2 µm to about 5 µm. Typically, such a fiber is formed by a single extruder. The homogeneous meltblown fiber 105 can generally be a discontinuous fiber and has a length such that its aspect ratio (e.g., length:diameter ratio) is greater than about 1,000:1, or greater than 5,000:1, or greater than 7,500:1, or greater than 20,000:1, or greater than about 30,000:1, or greater than about 50,000:1, or in some embodiments, it can be substantially continuous throughout the nonwoven web 100.

[0038] bicomponent fibers

[0039] The bicomponent meltblown fiber 103 disclosed herein is preferably a meltblown fiber with a diameter ranging from 1 µm to 25 µm, or more particularly from about 2 µm to about 20 µm, or from about 2 µm to about 10 µm, or from about 2 µm to about 5 µm. Typically, such a fiber is formed by two or more extruders. The bicomponent meltblown fiber 103 can generally be a discontinuous fiber and has a length such that its aspect ratio (e.g., length:diameter ratio) is greater than about 1,000:1, or greater than 5,000:1, or greater than 7,500:1, or greater than 20,000:1, or greater than about 30,000:1, or greater than about 50,000:1, or in some embodiments, it can be substantially continuous throughout the nonwoven web 100.

[0040] Secondary fiber materials

[0041] The secondary fiber material forming fiber 101 may be selected from the group consisting of one or more polyester fibers, polyamide fibers, cellulose-derived fibers (such as rayon fibers and wood pulp fibers), multicomponent fibers (such as sheath-core type multicomponent fibers), natural fibers (such as silk fibers, wool fibers, or cotton fibers), or conductive fibers, or mixtures of two or more such secondary fiber materials. Other types of secondary fiber materials may be used, such as polyethylene fibers and polypropylene fibers, as well as mixtures of two or more other types of secondary fiber materials. The secondary fiber material may be microfibers, or it may be coarse fibers with an average diameter of about 300 μm to about 1,000 µm.

[0042] In at least some embodiments, the secondary fiber material of the fiber 101 forming the web 100 of this disclosure may be absorbent fiber in some embodiments. As an example, such absorbent fiber may be fiber formed by various pulping processes, such as kraft pulp, sulfite pulp, thermomechanical pulp, etc. The pulp fiber may include cork fibers having an average fiber length greater than 1 mm, and specifically about 2 to 5 mm, based on a length-weighted average. Such cork fibers include, but are not limited to, northern cork, southern cork, redwood, red juniper, hemlock, pine (e.g., southern pine), spruce (e.g., black spruce), combinations thereof, etc. Hardwood fibers, such as eucalyptus, maple, birch, poplar, etc., may also be used. In some cases, eucalyptus fiber may be particularly desirable for increasing the softness of the web. Eucalyptus fiber can also enhance brightness, increase opacity, and alter the pore structure of the web to enhance its wicking capacity. Furthermore, if desired, secondary fibers obtained from recycled materials may be used, such as fiber pulp from sources such as newsprint, recycled paperboard, and office waste paper. In addition, other natural fibers can also be used in this invention, such as Manila hemp, Indian grass, milkweed, pineapple leaves, etc. Furthermore, synthetic fibers may also be used in some cases.

[0043] Other absorbent materials can be used in conjunction with pulp fibers, such as superabsorbents in the form of fibers, granules, gels, etc. Generally, a superabsorbent is a water-swellable material capable of absorbing at least about 20 times its own weight, and in some cases, at least about 30 times its own weight, in an aqueous solution containing 0.9% by weight of sodium chloride. Superabsorbents can be formed from natural, synthetic, and modified natural polymers and materials. Examples of synthetic superabsorbent polymers include alkaline earth metal salts and ammonium salts of poly(acrylic acid) and poly(methacrylic acid), poly(acrylamide), poly(vinyl ether), copolymers of maleic anhydride with vinyl ether and α-olefins, poly(vinylpyrrolidone), poly(vinylmorpholinone), poly(vinyl alcohol), and mixtures and copolymers thereof. Furthermore, superabsorbents include natural polymers and modified natural polymers, such as hydrolyzed acrylonitrile-grafted starch, acrylic acid-grafted starch, methylcellulose, deacetylated chitosan, carboxymethyl cellulose, hydroxypropyl cellulose, and natural gums such as alginate, xanthan gum, locust bean gum, etc. A mixture of natural and fully or partially synthetic superabsorbent polymers can also be used in this invention.

[0044] First polymer component and third polymer component

[0045] As discussed above, the first and third polymer components are typically thermoplastics and are selected to provide beneficial strength properties for the nonwoven web 100. Therefore, the first and / or third polymer components can be selected from those polymeric materials that produce strong polymer fibers, such as polypropylene. Other exemplary polymeric materials that may be suitable for the first and / or third polymeric components of the nonwoven web 100 include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and nylon 6 (polyamide 6). Of course, the first and / or third polymeric components can utilize other suitable polymeric materials that have similar properties to polypropylene or other listed polymeric materials and / or produce fibers with similar properties. In a further embodiment, the first and / or third polymeric components may comprise a single polymeric material described above, or may be a combination of polymeric materials blended together and discharged through a single extruder.

[0046] As discussed in the various embodiments of this disclosure, the nonwoven web 100 may comprise only a first polymer component selected from the aforementioned polymeric materials, which forms homogeneous meltblown fibers 105 and includes one component of bicomponent meltblown fibers 103. In embodiments of the web 100 having a first polymer component and a third polymer component—where the first polymer component forms homogeneous meltblown fibers 105 and the third polymer component includes one component of bicomponent meltblown fibers 103—the first and third polymer components may be selected from the aforementioned polymeric materials, but may be different polymeric materials.

[0047] Second polymer component

[0048] As discussed above, the second polymer component is typically a thermoplastic and is selected to provide beneficial softness properties for the nonwoven web 100. Therefore, the second polymer component can be selected from those polymer materials that produce polymer fibers with a soft feel, such as polyethylene. Of course, other suitable polymeric materials can be used for the second polymer component, which have similar properties to polyethylene and / or produce fibers with similar properties. Furthermore, the second polymer component can comprise a single polymeric material as described above, or it can be a combination of such polymeric materials discharged through a single extruder. Although in the case of a part of a bicomponent fiber, the extruder for discharging the second polymeric component can operate in close coordination with a second extruder discharging another different polymeric component to form the bicomponent fiber.

[0049] Example fabric

[0050] Various example webs 100 are formed according to various aspects of this disclosure and tested to determine specific properties in terms of softness, strength, and flexibility. A first example web is formed according to alternative method 200, wherein an outer meltblown die 216 is connected to extruders 14, 14” and configured to form bicomponent meltblown fibers 220. An inner meltblown die 218 is connected to extruder 14' and configured to form homogeneous meltblown fibers 221. Thus, in the formation of these first examples (hereinafter referred to as layered examples (LE) 1-6), a first web structure is formed by a first forming device (e.g., forming device 210a) comprising bicomponent meltblown fibers 220 and homogeneous meltblown fibers 221, and a secondary fiber material 232. Due to the meltblown... The die 214 is positioned relative to the airflow 234 of the apparatus 210a, and the bicomponent meltblown fibers 220 are arranged close to the forming surface 254 at a higher concentration. Then, a second mixture of the bicomponent meltblown fibers 220, homogeneous meltblown fibers 221, and secondary fiber material 232 formed by the second forming apparatus (e.g., forming apparatus 210b) is applied to the first web structure to form the final web structure, as in examples LE1-6. Due to the placement of the airflow 234 of the apparatus 210b, the second mixture is deposited, causing the bicomponent meltblown fibers 220 to be arranged away from the first web structure at a higher concentration.

[0051] Example LE1-6 is formed with a total basis weight of 70 gsm, and the secondary fiber material 232 used is pulp fluff. Polypropylene is used as the first polymer component, and polyethylene is used as the second polymer component, forming a bicomponent fiber with an ABA-shaped cross-section. No separate third polymer component is used. The basis weight of the first outer layer formed by the first device 210a and the second outer layer formed by the second device 210b are each approximately 25% of the total basis weight of the example web. The basis weight of the central layer, representing a mixture of homogeneous meltblown fiber 221 and pulp fluff, formed by the first and second devices 210a, 210b, is approximately 50% of the total basis weight of the example web.

[0052] Specific characteristics and measured performance properties of the example webs (including example webs LE1-6) are shown in Table 1 below. For example, Table 1 includes information on the total amount of secondary fiber material (e.g., pulp fluff), the first polymer component (e.g., polypropylene or PP), and the second polymer component (e.g., polyethylene or PE). Table 1 also reports the weight percentage (PE wt%) of polyethylene within the bicomponent meltblown fiber 220. For example, a 5% weight percentage value indicates that the polyethylene component of the bicomponent meltblown fiber 220 accounts for approximately 5% of the total weight of the bicomponent meltblown fiber 220. While such figures may be difficult to measure from the formed example webs LE1-6, such weight percentage values ​​can be readily determined from the forming process conditions—such as the flux of the first or third polymer component relative to the second polymer component in the formation of the bicomponent meltblown fiber 220. In other words, the bicomponent meltblown fiber 220 contains 5 wt% polyethylene (and therefore 95 wt% polypropylene). The total PE% measure of the web indicates the percentage of the total amount of polyethylene present in the web by its total weight. For example, a web structure with a length of 10 cm, a width of 20 cm, and a basis weight of 70 gsm will weigh 1.4 g. Therefore, a web total PE% value of 1.5% means that the web contains a total of 1.4 g × 0.015 = 0.021 g of PE.

[0053] Table 2 reports the performance metrics for example webs LE1-6. More specifically, the strength of example webs LE1-6 was tested according to the CDT strength test method described herein, their softness was tested according to the TS7 softness test method described herein, and their flexibility was tested according to the cup pressure test method described herein. Table 2 also reports the normalized strength parameter. This normalized strength parameter is the CDT strength value of the example web divided by the total polymer content of the example web. Since the total polymer content varies in the example webs and comparison webs, this metric may help to understand the unique strength characteristics of the example webs by observing the CDT strength value achieved relative to the polymer content of the example webs—polymer content is the primary driver of CDT strength values. For example, a higher normalized strength value indicates a relatively higher CDT strength value achieved for a given level of polymer content.

[0054] Formed different Figure 1The second example webs of web structure 100 are described. These second example webs are formed as a homogeneous composition having a bicomponent meltblown fiber 220 and a secondary fiber material 232. These second example webs (hereinafter referred to as HE1-3) use pulp fluff for the secondary fiber material 232, and use polypropylene and polyethylene for the first polymer component and the second polymer component, respectively. Example webs HE1-3 are formed in a similar manner to examples LE1-6, except that example HE1-3 is formed by a single device such as device 210a. For the HE1-3 example, apparatus 210a has meltblown dies 216 on both sides of the airflow 234, each meltblown die being connected to extruders 214, 214” and configured to form bicomponent meltblown fibers 220. A composite mixture of the bicomponent meltblown fibers 220 and pulp fluff is collected on forming surface 258 to produce the example web HE1-3. The example web HE1-3 is formed at approximately 70 gsm, wherein pulp accounts for approximately 42 gsm of the total 70 gsm basis weight, and the bicomponent meltblown fibers 220 account for approximately 28 gsm of the total 70 gsm basis weight.

[0055] Two example control webs were also formed. The first control web (CW1) is a homogeneous web consisting of pulp fluff and homogeneous meltblown fibers 221 containing only polypropylene. The CW1 example was formed in a manner similar to that of the example webs in HE 1-3. The second control web (CW2) is a homogeneous web consisting of pulp fluff and homogeneous meltblown fibers 221 containing only polyethylene. The CW2 example was formed in a manner similar to that of the CW1 example web. The PE weight % values ​​of 0% and 100% for the CW1 and CW2 examples indicate the formation of the polyethylene-free CW1 example web, where the meltblown fibers are homogeneous polypropylene fibers, and the formation of the polypropylene-free CW2 example web, where the meltblown fibers are homogeneous polyethylene fibers.

[0056] Comparative webs were also formed and measured to determine the same strength, softness, and flexibility parameters as examples LE1-6, CW1, CW2, and HE1-3. These first comparative webs (hereinafter referred to as Comparative Examples 1-3) were formed according to aspects of U.S. Patent No. 6,028,018 to Amundson et al., which describes a layered nonwoven web structure comprising a homogeneous polyethylene fiber outer layer and a homogeneous polypropylene fiber central layer. These comparative webs 1-3 were formed using three separate forming devices 310a-c according to the method 300 disclosed herein. The first and third forming devices 310a, 310c are configured to form homogeneous polyethylene fibers (as shown in 100% PE weight % values), and the second forming device 310b is configured to form homogeneous polypropylene fibers. The meltblown and pulp mixture (e.g., forming the outer region of the shaped web) of the first forming apparatus and the third forming apparatus 310a, 310c is 20 gsm for the web of Comparative Example 1, while the first forming apparatus and the third forming apparatus 310a, 310c form a mixture of 25 gsm for the webs of Comparative Examples 2 and 3.

[0057] It should be noted that the example webs LE1-6 and HE1-3 were formed at a polymer melt flow rate of 2.0–3.0 PIH per inch of die width per hour. Similar webs with similar properties, ranging from approximately 1.0 PIH to 6.0 PIH as described in Table 2, have also been manufactured. The air temperatures used were between 190°C and 235°C, and the pressures between 20 kPa and 45 kPa. The melt temperature of PP was also considered; resin-dependent 420–430°C, 380–390°C; based on the melt temperature of 380–440°C resin.

[0058] Those skilled in the art will understand the adjustments.

[0059] For efficient and high-speed production, it is important to balance the drawing air settings to maintain a continuous meltblown flow.

[0060] Offline vacuum:

[0061] Melting temperature:

[0062] Airflow:

[0063]

[0064]

[0065] As can be seen from Tables 1 and 2, the LE1-6 example webs achieve a superior combination of softness and strength compared to the HE1-3 example webs and Comparative Examples 1-3 webs. For example, Comparative Examples 1-3 webs do not achieve a CDT strength value greater than 211 gf. A typical commercially acceptable CDT strength value is greater than 225 gf, or even greater than 250 gf for some products. In contrast, all LE1-6 example webs achieve a CDT strength value greater than 225 gf, with LE 1-4 achieving a CDT strength value greater than 250 gf. Furthermore, although all HE1-3 example webs achieve a CDT strength value greater than 225 gf, they perform worse in the TS7 softness metric compared to the LE1-6 example webs.

[0066] Although the LE1-6 example webs achieve a superior combination of strength and softness compared to the comparative examples 1-3 and HE1-3, it may be advantageous to use webs with a similar construction to the HE1-3 example webs in certain situations. For example, HE2 has a higher CDT strength value and only a slightly lower TS7 softness value compared to the LE5 example web; both the LE5 and H2 example webs utilize bicomponent fiber 103 with 15% by weight polyethylene. Furthermore, although LE2 outperforms HE2 in both strength and softness, in some cases, other considerations such as processability may make HE2 a better choice.

[0067] The normalized strength parameter also provides an indication of the uniqueness of the LE1-6 example webs. For example, the LE1-6 example webs achieve higher normalized strength values ​​compared to the comparative examples 1-3, and almost all example webs achieve normalized strength values ​​greater than those of the HE1-3 example webs. Specifically, each of the LE4-6 example webs achieves a higher normalized strength value compared to the corresponding HE1-3 example webs with the same PE weight % value. This indicates that the LE1-6 example webs (and especially the LE4-6 example webs) can achieve higher strength at a given polymer level compared to alternative web structures, thus allowing the desired strength target to be achieved with a relatively smaller polymer content in the web structure according to the LE1-6 example webs.

[0068] Example Implementation Plan

[0069] According to a first example embodiment of the nonwoven web 100 disclosed herein, the total basis weight of the nonwoven web 100 is between about 50 gsm and about 80 gsm, and the absorbent material accounts for about 60% to about 80% of the total basis weight of the web 100. Homogeneous fibers 105 account for about 17% to about 37% of the total basis weight of the web 100, and bicomponent fibers 103 account for about 3% to about 20% of the total basis weight of the web 100.

[0070] In these first example embodiments, the homogeneous fiber 105 is formed from a first polymer component. The bicomponent fiber 103 is formed from a second polymer component and either a first polymer component or a third polymer component. In the first example embodiments of the web 100, the total content of the second polymer component is from about 0.2% to about 5% of the total weight of the web 100. In a more specific embodiment, the total content of the second polymer component is from about 0.2% to about 4%, or from about 0.2% to about 3%, or from about 0.2% to about 2.5% of the total weight of the web 100. Therefore, the total weight of the combined first polymer component and third polymer component (if any) is from about 95% to about 99.8%, or from about 96% to about 99.8%, or from about 97% to about 99.8%, or from about 97.5% to about 99.8% of the total weight of the web 100.

[0071] Furthermore, the second polymer component accounts for approximately 1.5% to approximately 25% of the total weight of the bicomponent fibers 103. In more specific examples of these first embodiments, the second polymer component accounts for approximately 1.5% to approximately 20% or approximately 1.5% to approximately 15% of the total weight of the bicomponent fibers 103. Therefore, the first polymer component or the third polymer component accounts for approximately 75% to approximately 98.5%, or approximately 80% to approximately 98.5%, or approximately 85% to approximately 98.5% of the total weight of the bicomponent fibers 103.

[0072] These first example webs may have a CDT strength value greater than or equal to about 228 gf, or greater than or equal to about 274 gf, or greater than or equal to about 311 gf, or between about 228 gf and about 312 gf, or between about 242 gf and about 312 gf, or between about 274 gf and about 312 gf, or between about 280 gf and about 312 gf. Additionally, in combination with these CDT strength values, these example webs may have a TS7 softness value less than or equal to about 3.86, or less than or equal to about 3.60, or less than or equal to about 3.39, or less than or equal to about 3.25, or between about 3.86 and about 2.83, or between about 3.60 and about 2.83. More specific examples of these examples may have a CDT strength value between about 228 gf and about 312 gf and a TS7 softness value between about 2.83 and about 3.86. In even more specific instances, the CDT strength value can be between 228 gf and 311 gf, and the TS7 softness value can be between about 2.83 and about 3.60; or the CDT strength value can be between about 242 gf and about 280 gf, and the TS7 softness value can be between about 2.83 and about 3.60. In combination with any of these softness and strength values, these first examples may additionally have a cup flexibility value of about 903 gf*mm to about 1358 gf*mm, or about 903 gf*mm to about 1240 gf*mm, or about 903 gf*mm to about 1085 gf*mm (the smaller the number, the better the flexibility).

[0073] According to a second exemplary embodiment of the nonwoven web 100 disclosed herein, the total basis weight of the nonwoven web 100 is between about 80 gsm and about 120 gsm, and the absorbent material accounts for about 65% to about 85% of the total basis weight of the web 100. Homogeneous fibers 105 account for about 12.5% ​​to about 33% of the total basis weight of the web 100, and bicomponent fibers 103 account for about 2.5% to about 17.5% of the total basis weight of the web 100.

[0074] In these second example embodiments, the homogeneous fiber 105 is formed from a first polymer component. The bicomponent fiber 103 is formed from a second polymer component and either a first polymer component or a third polymer component. In a first example embodiment of the web 100, the total content of the second polymer component is from about 0.2% to about 3.5% of the total weight of the web 100. In a more specific embodiment, the total content of the second polymer component is from about 0.2% to about 3%, or from about 0.2% to about 2.5%, or from about 0.2% to about 2.0% of the total weight of the web 100. Therefore, the total weight of the combined first polymer component and third polymer component (if any) is from about 96.5% to about 99.8%, or from about 97% to about 99.8%, or from about 97.5% to about 99.8%, or from about 98% to about 99.8% of the total weight of the web 100.

[0075] Furthermore, the second polymer component accounts for approximately 1.5% to approximately 25% of the total weight of the bicomponent fibers 103. In more specific examples of these first embodiments, the second polymer component accounts for approximately 1.5% to approximately 20% or approximately 1.5% to approximately 15% of the total weight of the bicomponent fibers 103. Therefore, the first polymer component or the third polymer component accounts for approximately 75% to approximately 98.5%, or approximately 80% to approximately 98.5%, or approximately 85% to approximately 98.5% of the total weight of the bicomponent fibers 103.

[0076] According to a third exemplary embodiment of the nonwoven web 100 of this disclosure, the total basis weight of the nonwoven web 100 is between 20 gsm and 50 gsm, and the absorbent material accounts for about 50% to about 70% of the total basis weight of the web 100. Homogeneous fibers 105 account for about 25% to about 45% of the total basis weight of the web 100, and bicomponent fibers 103 account for about 5% to about 25% of the total basis weight of the web 100.

[0077] In these second example embodiments, the homogeneous fiber 105 is formed from a first polymer component. The bicomponent fiber 103 is formed from a second polymer component and either a first polymer component or a third polymer component. In a first example embodiment of the web 100, the total content of the second polymer component is from about 1.0% to about 7.0% of the total weight of the web 100. In a more specific embodiment, the total content of the second polymer component is from about 1.5% to about 7.0%, or about 2.0% to about 7.0%, or about 2.5% to about 7.0% of the total weight of the web 100. Therefore, the total weight of the combined first polymer component and third polymer component (if any) is from about 93% to about 99%, or about 93% to about 98.5%, or about 93% to about 98%, or about 93% to about 97.5% of the total weight of the web 100.

[0078] Furthermore, the second polymer component accounts for approximately 1.5% to approximately 25% of the total weight of the bicomponent fibers 103. In more specific examples of these first embodiments, the second polymer component accounts for approximately 1.5% to approximately 20% or approximately 1.5% to approximately 15% of the total weight of the bicomponent fibers 103. Therefore, the first polymer component or the third polymer component accounts for approximately 75% to approximately 98.5%, or approximately 80% to approximately 98.5%, or approximately 85% to approximately 98.5% of the total weight of the bicomponent fibers 103.

[0079] According to a fourth exemplary embodiment of the nonwoven web 100 of this disclosure, the total basis weight of the nonwoven web 100 is between about 50 gsm and about 80 gsm, and the absorbent material accounts for about 60% to about 75% of the total basis weight of the web 100. The fourth exemplary embodiment does not have homogeneous fibers 105, but has bicomponent fibers 103 arranged homogeneously throughout the nonwoven web 100. In these fourth exemplary embodiments, the bicomponent fibers 103 account for about 25% to about 40% of the total basis weight of the web 100.

[0080] In these fourth example embodiments, the bicomponent fiber 103 is formed of a first polymer component and a second polymer component. In the fourth example embodiment of the web 100, the total content of the second polymer component is about 2% to about 15% of the total weight of the web 100. In a more specific embodiment, the total content of the second polymer component is about 3% to about 12.5%, or about 4% to about 10%, or about 4% to about 8% of the total weight of the web 100. Therefore, the total weight of the first polymer component is about 85% to about 98%, or about 87.5% to about 97%, or about 90% to about 96%, or about 92% to about 96% of the total weight of the web 100.

[0081] Furthermore, the second polymer component comprises about 5% to about 30% of the total weight of the bicomponent fibers 103. In more specific examples of these first embodiments, the second polymer component comprises about 7.5% to about 25% or about 10% to about 20% of the total weight of the bicomponent fibers 103. Therefore, the first polymer component or the third polymer component comprises about 70% to about 95%, or about 75% to about 92.5%, or about 80% to about 90% of the total weight of the bicomponent fibers 103.

[0082] These fourth example webs may have a CDT strength value greater than or equal to about 237 gf, or greater than or equal to about 283 gf, or between about 237 gf and about 347 gf, or between about 237 gf and about 283 gf, or between about 283 gf and about 347 gf. Additionally, in combination with these CDT strength values, these example webs may have a TS7 softness value less than or equal to about 4.66, or less than or equal to about 3.56, or between about 4.66 and about 3.47, or between about 4.66 and about 3.56, or between about 3.27 and about 3.56. More specific examples of these examples may have a CDT strength value between about 237 gf and about 283 gf and a TS7 softness value between about 3.47 and about 3.56. In even more specific examples, the CDT strength value may be between about 283 gf and about 347 gf, and the TS7 softness value may be between about 3.47 and about 4.66.

[0083] Web forming

[0084] The co-formed web 100 according to this disclosure is typically manufactured by a process in which at least one meltblown die (e.g., two) is arranged near a chute through which absorbent material is added simultaneously with the formation of the web. Some examples of such co-forming techniques are disclosed in the granted... Anderson et al. U.S. Patent No. 4,100,324, granted Georger et al. U.S. Patent No. 5,350,624; and granted Georger U.S. Patent No. 5,508,102 and the grant of Keck et al. U.S. Patent Application Publication No. 2003 / 0200991 and Grant Dunbar et al. All of these patents are incorporated herein by reference in their entirety in U.S. Patent Application Publication No. 2007 / 0049153 for all purposes.

[0085] refer to Figure 2This paper describes an exemplary method 200 for forming an exemplary web 100 according to the present disclosure. Method 200 includes a first apparatus 210a for forming a co-shaped web of the present disclosure. In this embodiment, apparatus 210a includes granule funnels 212, 212', 212" of extruders 214, 214', 214" into which a polymer component or blend of polymer components can be introduced. Extruders 214, 214', 214" each have an extrusion screw (not shown) driven by a conventional drive motor (not shown). As the polymer component advances through extruders 214, 214', 214" the polymer component is gradually heated to a molten state due to the rotation of the extrusion screw by the drive motor. Heating can be accomplished in multiple discontinuous steps, with the temperature gradually increasing as it advances toward the two meltblown dies 216 and 218 through the discontinuous heating zones of the extruders 214, 214', and 214'. The meltblown dies 216 and 218 can be another heating zone where the temperature of the polymer component is maintained at an elevated level for extrusion.

[0086] Each meltblown die 216 and 218 is configured such that two refined airflows of each die converge to form a single airflow that entrains and draws the molten polymer line 220 as it exits the orifice or aperture 224 in each meltblown die. The molten polymer line 220 is formed as fibers with a small diameter (which may be microfibers depending on the degree of refinement), typically smaller than the diameter of the orifice 224. Thus, each meltblown die 216 and 218 has corresponding single airflows 226 and 228 containing entrained meltblown fibers formed from the polymer component.

[0087] Airflows 226 and 228 containing meltblown polymer fibers (e.g., bicomponent meltblown fiber 103 and / or homogeneous meltblown fiber 105) are aligned to converge in the impact zone 230. Typically, meltblown dies 216 and 218 are arranged at an angle relative to the forming surface, as per the given... Georger et al. As described in U.S. Patent Nos. 5,508,102 and 5,350,624. Reference Figure 4 For example, meltblown dies 216 and 218 can be oriented at an angle θ measured from a plane "A" tangent to the two dies 216 and 218. As shown, plane "A" is approximately parallel to the forming surface 258. Figure 2 Typically, each die 216 and 218 is set at an angle ranging from about 30 degrees to about 75 degrees, in a further embodiment at an angle ranging from about 35 degrees to about 60 degrees, and in a further embodiment at an angle ranging from about 40 degrees to about 55 degrees. Dies 216 and 218 may be oriented at the same or different angles. In fact, the texture of the co-formed web can actually be enhanced by orienting one die at an angle different from that of the other die.

[0088] refer to Figure 4 The molds 216 and 218 are spaced apart by a distance α. Generally, the distance α can range up to about 41 cm (16 inches). In some cases, α can range from about 13 cm (5 inches) to about 25 cm (10 inches). In other cases, α can range from about 15 cm (6 inches) to about 21 cm (8 inches). Importantly, the distance α between the meltblown molds and the angle θ of each meltblown mold determine the position of the forming zone 230.

[0089] The distance from the forming zone 230 to the tip of each meltblown die (i.e., distance X) should be set to minimize the dispersion of each primary airflow 226 and 228 of the fiber. For example, this distance can range up to about 41 cm (16 inches). Ideally, this distance should be greater than 6 cm (2.5 inches). For example, for a distance X ranging from about 6 cm (2.5 inches) to 16 cm (6 inches), the distance from the tip of each meltblown die assembly to the forming zone 230 can be determined using the following formula from the spacing α between the die tips and the die angle θ:

[0090]

[0091] Generally, dispersion of the flow 256 can be minimized by selecting an appropriate vertical forming distance (i.e., distance β) before the flow 256 contacts the forming surface 258. β is the distance from the tip of the meltblown dies 216, 218 to the forming surface 258. To minimize dispersion, a shorter vertical forming distance is generally desirable. This must be balanced by the need for the extruded fibers to solidify from their viscous, semi-molten state before contacting the forming surface 258. For example, the vertical forming distance β can range from approximately 7 cm (3 inches) to approximately 38 cm (15 inches) from the tip of the meltblown die. Ideally, this vertical distance β can be from approximately 10 cm (4 inches) to approximately 28 cm (11 inches) from the tip of the die.

[0092] A key component of the vertical forming distance β is the distance (i.e., distance Y) between the forming zone 230 and the forming surface 258. The forming zone 230 should be positioned such that the integrated flow travels only a minimum distance (Y) to reach the forming surface 258, minimizing the dispersion of entrained meltblown fibers. For example, the distance (Y) from the forming zone to the forming surface can range up to approximately 31 cm (12 inches). Ideally, the distance (Y) from the point of impact to the forming surface can range from approximately 5 cm (3 inches) to approximately 18 cm (7 inches). The distance from the forming zone 230 to the forming surface 258 can be determined using the following formula from the vertical forming distance β, the spacing (β) between the die tips, and the die angle (θ):

[0093]

[0094] The secondary fibrous material carrying gas is introduced into the forming zone 230 via a flow 234 emanating from nozzle 244. Generally, nozzle 244 is positioned such that its vertical axis is substantially perpendicular to the forming surface 258.

[0095] In some cases, it may be desirable to cool the secondary airflow 234. Cooling the secondary airflow 234 can accelerate the quenching of molten or viscous meltblown fibers and provide a shorter distance between the meltblown die tip and the forming surface 258, which can be used to minimize fiber dispersion. For example, the temperature of the secondary airflow 234 can be cooled to about 65 to about 85 degrees Fahrenheit.

[0096] By balancing the meltblown fiber flows 226 and 228 with the secondary air flow 234, the desired die angle θ of the meltblown die, the vertical forming distance (β), the distance between the tips of the meltblown die (α), the distance between the forming zone and the tip of the meltblown die (X), and the distance between the forming zone and the forming surface (Y), the controlled integration of secondary fiber materials can be provided within the meltblown fiber flow.

[0097] Refer again Figure 2 Secondary fiber material 232 is added to two streams 226 and 228 of meltblown polymer fibers 220 and 221, respectively, and turbulent mixing of streams 226, 228, and 234 is formed at the impact zone 230. The introduction of secondary fiber material 232 into the two streams 226 and 228 of meltblown polymer fibers 220 and 221 to form an integrated airflow is designed to produce a hierarchical distribution of secondary fiber material 232 in the combined streams 226 and 228 of the meltblown fibers. This is achieved by merging a secondary airflow 234 containing secondary fiber material 232 between the two streams 226 and 228 of meltblown polymer fibers 220 and 221, such that all three airflows converge in a controlled manner. Because they remain relatively viscous and semi-molten after forming, meltblown polymer fibers 220 and 221 can simultaneously adhere to and entangle with the secondary fiber material 232 upon contact to form a coherent nonwoven structure.

[0098] To achieve fiber merging, any conventional equipment can be used, such as a shunting roller 236 device with multiple teeth 238 adapted to separate the pads or tufts 240 of secondary fibers into individual fiber materials. The pads or tufts 240 of secondary fiber material fed to the shunting roller 236 can be pulp fiber sheets (if a two-component mixture of polymer fibers and secondary pulp fibers is required), cut fiber pads (if a two-component mixture of polymer fibers and secondary cut fibers is required), or both pulp fiber sheets and cut fiber pads (if a three-component mixture of polymer fibers, secondary cut fibers, and secondary pulp fibers is required).

[0099] When employed, sheets or pads 240 of the secondary fiber material 232 are fed to the evacuation roller 236 via a roller assembly 242. After the teeth 238 of the evacuation roller 236 have separated the fiber pads into individual secondary fiber materials 232, the individual fibers are conveyed through nozzles 244 to two streams 226 and 228 of meltblown polymer fibers 220 and 221. A housing 246 surrounds the evacuation roller 236 and provides a channel or gap 248 between the housing 246 and the surface of the teeth 238 of the evacuation roller 236. Gas, such as air, is supplied through a gas conduit 250 to the channel or gap 248 between the surface of the evacuation roller 236 and the housing 246.

[0100] The gas conduit 250 can enter the channel or gap 248 at the junction 252 of the nozzle 244 and the gap 248. In an exemplary aspect, the dual-ring manifold serves as a dilution air fan 272, providing a uniform air distribution to deliver air into the gas conduit 250. The gas is supplied in sufficient quantity to serve as a medium for conveying the secondary fibrous material 232 through the nozzle 244. The gas supplied from the conduit 250 also facilitates the removal of the secondary fibrous material 232 from the teeth 238 of the evacuation roller 236. It is anticipated that additives and / or other materials may be added to or entrained in the airflow to treat the secondary fibrous material 232.

[0101] A separate stripping air fan 274 is used to provide a secondary stripping airflow entering the system at contact 252 to aid in the removal of secondary fiber material 232 from the teeth 238 of the evacuation roller 236. The separate dilution air fan 272 and stripping air fan 274 allow the operator to balance the stripping airflow, allowing for optimal fiber release from the teeth 238 and an increased flow rate of the secondary airflow 234.

[0102] Generally, the individual secondary fiber material 232 is conveyed through the nozzle 244 at approximately the speed at which it exits the teeth 238 of the dispersing roller 236. In other words, the secondary fiber material 232 typically maintains its velocity in magnitude and direction relative to the point of exit from the teeth 238 of the dispersing roller 236 as it exits and enters the nozzle 244. This device, in imparting... Anderson et al. A more detailed discussion is found in U.S. Patent No. 4,100,324.

[0103] If needed, the velocity of the secondary airflow 234 can be adjusted to obtain co-formed structures with different properties. For example, when the velocity of the secondary airflow is adjusted to be greater than the velocity of each stream 226 and 228 of the meltblown polymer fibers 220 and 221 when in contact with the impact zone 230, the absorbent fiber 232 is incorporated into the co-formed nonwoven web in a gradient structure. That is, the secondary fiber material 232 has a higher concentration between the outer surfaces of the co-formed nonwoven web than at the outer surface. On the other hand, when the velocity of the secondary airflow 234 is less than the velocity of each stream 226 and 228 of the meltblown polymer fibers 220 and 221 when in contact with the impact zone 230, the secondary fiber material 232 is incorporated into the co-formed nonwoven web in a substantially homogeneous manner. That is, the concentration of the secondary fiber material 232 is substantially the same throughout the co-formed nonwoven web. This is because the low-velocity flow of the secondary fiber material 232 is drawn into the high-velocity flow of the meltblown polymer fibers to enhance turbulent mixing, which results in a uniform distribution of the secondary fiber material 232.

[0104] To transform the composite flow 256 of meltblown polymer fibers 220, 221 and secondary fiber material 232 into a co-shaped nonwoven structure 254, a collection device is located in the path of the composite flow 256. The collection device may be driven by a roller 260 and, as... Figure 2 The rotating forming surface 258 (e.g., belt, drum, thread, fabric, etc.) is indicated by the middle arrow 262. Driven by roller 260, the rotating forming surface 258 moves longitudinally in accordance with arrow 262. The combined flow of meltblown polymer fibers and secondary fiber material 232 is collected on the surface of the forming surface 258 as a fiber coherent matrix to form a co-shaped nonwoven structure 254.

[0105] Fiber deposition can be achieved by a negative pressure unit or an offline exhaust system 280 (as per reference). Figure 4 (As shown) A line vacuum is supplied to assist. Unlike conventional machines, the line vacuum can have multiple zones in the longitudinal direction, such as three zones. In the case of three zones, the first zone is located upstream in the longitudinal direction of the forming area 230, the second zone is directly below the nozzle 244 and the forming area 230, and the third zone is located downstream in the longitudinal direction of the forming area 230. In an exemplary aspect, the second zone has the highest airflow, the first zone has the lowest airflow, and the third zone has an airflow higher than the first zone but lower than the second zone. If found to be optimal, they can also supply the same amount of airflow.

[0106] According to the aforementioned apparatus 210a and related processes, the secondary fiber material is interconnected and held within the meltblown polymer fibers through mechanical entanglement of the polymer fibers and the secondary fiber material. The individual mechanical entanglement and interconnection of the polymer fibers and the secondary fiber material can form a coherently integrated fiber structure (e.g., a co-formed nonwoven structure 254). This coherently integrated fiber structure can be formed from polymer fibers and secondary fiber materials without any adhesive, molecular bonds, or hydrogen bonds between the two different types of fibers.

[0107] like Figure 2 As shown, method 200 may further employ a second device 210b that is substantially similar to device 210a. For example, device 210b may include the same components (in... Figure 2 (Similarly, device 210b is referred to as the same component within device 210a). Furthermore, device 210b can operate in a manner similar to that described for device 210a. Of course, devices 210a and 210b do not necessarily have to operate in exactly the same way, for example, using the exact same process settings. Instead, settings—such as airflow velocity, material throughput, vacuum level, etc.—can be varied between devices 210a and 210b to produce different co-formed structures with desired characteristics.

[0108] Regarding the nonwoven web 100 of this disclosure, apparatuses 210a and 210b can operate together to produce the described layered or homogeneous web structure. According to method 200, different fibers can be produced by meltblown dies 216 and 218 to aid in the formation of... Figure 1 The web 100 has a layered structure. For example, in method 200, the first die 216 of apparatus 210a can produce a flow 226 of bicomponent meltblown fibers 220, and extruders 214 and 214'' feed the die 216. Extruder 214 can extrude a first (or third) polymer component, while extruder 214'' can extrude a second polymer component, the first (or third) polymer component and the second polymer component merging in the first die 216 to form bicomponent fibers. Extruder 214' can extrude the first polymer component, thereby forming a flow 228 of homogeneous meltblown fibers 221 when the first polymer component is forced through the second die 218. The flow 226 of meltblown bicomponent meltblown fibers 220 can form bicomponent meltblown fibers 103 of the web 100, while the flow 228 of homogeneous meltblown fibers 221 forms homogeneous meltblown fibers 105 of the web 100.

[0109] Because the flow 226 of bicomponent fibers 220 is upstream relative to the secondary airflow 234 containing secondary fiber material 232, the bicomponent meltblown fibers 220 are arranged at a higher concentration closest to the forming surface 258 and form the first outer region of the web structure 254—ultimately forming the first outer region 102 of the web 100. Because the flow 228 of homogeneous meltblown fibers 221 is downstream relative to the secondary airflow 234 containing secondary fiber material 232, the homogeneous meltblown fibers 221 are arranged at a higher concentration away from the forming surface 258 on the subsurface (e.g., the top surface) of the web structure 254.

[0110] Web structure 254 is an intermediate structure formed by device 210a, which is then transferred to device 210b in the process according to method 200. Device 210b may differ from device 210a in that extruder 214' is located upstream of the secondary airflow 234 of device 210b, while extruders 214, 214” are located downstream of the secondary airflow 234 within device 210b. Within device 210b, extruder 214' and die 218—similar to those in device 210a—are responsible for extruding the first polymer component and forming homogeneous meltblown fibers 221. Extruders 214, 214” and die 216 of device 210b—again, similar to those in device 210a—are responsible for extruding the first (or third) polymer component and the second polymer component and forming bicomponent meltblown fibers 220.

[0111] Because the extruder 214' and die 218 of the second device 210b are located upstream of the secondary airflow 234, and the combined air and material flow 256 applies material to the web structure 254 from device 210a, the homogeneous meltblown fibers 221 formed by the second device 210b are applied to the web structure 254, which is arranged at a higher concentration near the subsurface of the web structure 254. In this way, the combined material of the homogeneous meltblown fibers 221 and the secondary fiber material 232 of the first and second devices 210a, 210b forms the central region of the final web 100, as... Figure 1The most clearly visible part is the extruder 214, 214'' and die 216 of the second device 210b, which are located downstream of the secondary airflow 234. The combined air and material flow 256 applies material to the web structure 254 from device 210a. The bicomponent meltblown fibers 220 formed by the second device 210b are applied to the web structure 254, which is arranged at a higher concentration away from the subsurface of the web structure 254. In this way, the combined bicomponent meltblown fibers 220 and secondary fiber material 232 of the second device 210b form the outer region of the shaped web 100. Applying the bicomponent meltblown fibers 220, homogeneous meltblown fibers 221 and secondary fiber material 232 from the second device 210b to the web structure 254 forms the nonwoven web 100.

[0112] Therefore, method 200 can be used to form a nonwoven web structure, such as nonwoven web 100, having a first outer region, a central region, and a second outer region, wherein the outer regions contain a higher concentration of bicomponent meltblown fibers than the central region. The central region contains a higher concentration of homogeneous meltblown fibers than either the first outer region or the second outer region. In some embodiments, the first outer region and / or the second outer region may not contain homogeneous meltblown fibers, and the central region may not contain bicomponent meltblown fibers.

[0113] The "flux" of material through extruders 214, 214', 214" affects the amount of material (e.g., homogeneous fiber / bicomponent fiber) from dies 216, 218 in the final web 100. In this way, by adjusting the flux of the polymer components through extruders 214, 214', 214", the basis weight of the bicomponent meltblown fiber 103 and the homogeneous meltblown fiber 105 in the formed web 100 can be adjusted to different levels. For example, increasing the throughput of the first (or third) and second polymer components through extruders 214, 214” and die 216 will proportionally increase the amount of bicomponent meltblown fibers 220 in stream 226, and thus increase the amount of bicomponent meltblown fibers 103 in the final shaped web 100. Similarly, increasing the throughput of the first polymer component through extruder 214’ and die 218 will proportionally increase the amount of homogeneous meltblown fibers 221 in stream 228, and thus increase the amount of homogeneous meltblown fibers 221 in the final shaped web 100. The amount of fiber 105. Reducing the throughput will correspondingly reduce the relative amounts of fibers 103 and 105 in the final shaped web 100. The preferred relative amounts of homogeneous meltblown fiber 105 to bicomponent meltblown fiber 103 and / or the preferred relative amounts of the first and third polymer components forming fibers 103 and 105 to the second polymer component have been detailed herein, and such levels can be achieved by adjusting the throughput of the polymer components through the extruders 214, 214', 214" and the dies 216, 218.

[0114] Furthermore, by increasing or decreasing the throughput of the first (or third) polymer component or the second polymer component through extruders 214, 214” and die 216 relative to each other, bicomponent meltblown fibers can be formed having different percentages of the first (or third) polymer component and the second polymer component based on the total weight of the bicomponent meltblown fibers. For example, according to aspects of this disclosure, by adjusting the throughput of the second polymer component through extruder 214” relative to the first (or third) polymer component through extruder 214, the amount of the second polymer component in the bicomponent meltblown fiber 220 (and thus the bicomponent meltblown fiber 103 in the web 100) can vary between about 1.5% and about 30% of the total weight of the bicomponent meltblown fibers.

[0115] Other configurations of the devices 210a and 210b are intended to produce nonwoven web structures according to various aspects of this disclosure. For example, device 210a may include only a die 216 configured to form bicomponent meltblown fibers 220, while device 210b includes both die 216 and die 218 to form bicomponent meltblown fibers 220 and monocomponent meltblown fibers 221, wherein die 216 is arranged downstream of die 218. In other embodiments, device 210b may include only a die 216 configured to form bicomponent meltblown fibers 220, while device 210a includes both die 216 and die 218 to form bicomponent meltblown fibers 220 and monocomponent meltblown fibers 221, wherein die 216 is arranged upstream of die 218.

[0116] Method 300 represents another process for forming nonwoven webs according to this disclosure. Method 300 is similar to Method 200, except that Method 300 employs three forming devices 310a, 310b, and 310c, as... Figure 3 As shown. Devices 310a, 310b and 310c are all similar to the previously described device 210a. The similarly marked parts in devices 310a, 310b and 310c are the same as the corresponding parts described with respect to device 210a.

[0117] Figure 3 The method begins in a manner similar to method 200. For example, the first die 216 of apparatus 310a is located upstream of the secondary airflow 234 and generates a flow 226 of bicomponent meltblown fibers 220, with extruders 214, 214'' feeding the die 216. The flow 226 of bicomponent fibers 220 is located upstream of the secondary airflow 234 containing secondary fiber material 232, and the bicomponent meltblown fibers 220 are arranged at a higher concentration closest to the forming surface 258, forming the first outer region of the web structure 254—ultimately forming the first outer region 102 of the web 100. Figure 3As shown, the flow 228 of homogeneous meltblown fiber 221 in device 310a is downstream of the secondary air flow 234 containing secondary fiber material 232, and thus the homogeneous meltblown fiber 221 formed by device 310a is arranged at a higher concentration away from the forming surface 258 on the secondary surface (e.g., the top surface) of the web structure 254.

[0118] The web structure 254 formed by apparatus 310a is transferred to apparatus 310b in the process according to process 300. Apparatus 310b differs from apparatus 310a in that it forms a composite flow 256 consisting of a flow combining secondary fiber material 232 and a flow of only homogeneous meltblown fibers 221. For example, apparatus 310b is shown having only an extruder 214' and a die 218 through which the first polymer components are extruded and passed through the die 218 to form homogeneous meltblown fibers 221. Therefore, the composite fiber material formed by apparatus 310b and applied to the web structure 254 formed by apparatus 310a comprises only secondary fiber material 232 and homogeneous meltblown fibers 221. In this way, process 300 is able to produce a larger (e.g., thicker; higher basis weight) central region 106 in the shaped nonwoven web 100 according to this disclosure. Although it is described herein as utilizing the first polymer component in the extruder 214' of device 310b, it should be understood that different polymer components (or polymer blends) may be used for device 310b, as in the formation of homogeneous meltblown fibers in device 310a (and / or device 310c).

[0119] After material from device 310b is applied to the web structure 254 formed by device 310a, a second intermediate structure 254' is formed, and the second intermediate structure 254' is fed to device 310c. Device 310c is similar to device 210b of method 200. For example, device 310c has an extruder 214' and a die 218 located upstream of the secondary airflow 234 of device 310c that operate to form homogeneous meltblown fibers 221. Extruders 214, 214” and die 216 are located downstream of the secondary airflow 234 of apparatus 310c. Therefore, the homogeneous meltblown fibers 221 formed by apparatus 310c are applied to the web structure 254' arranged at a higher concentration close to the web structure 254', contributing to the basis weight of the central region 106 of the final shaped web 100. Similarly, the homogeneous meltblown fibers 221 formed by apparatus 310c are applied to the web structure 254' arranged at a higher concentration away from the web structure 254', forming the outer regions 102, 104 of the final shaped web 100.

[0120] Therefore, method 300 can be used to form nonwoven web structures, such as nonwoven web 100, having a first outer region, a central region, and a second outer region, wherein the outer regions contain a higher concentration of bicomponent meltblown fibers than the central region. The central region contains a higher concentration of homogeneous meltblown fibers than either the first outer region or the second outer region. In some embodiments, the first outer region and / or the second outer region may be free of homogeneous meltblown fibers, and the central region may be free of bicomponent meltblown fibers. The advantage of method 300 over method 200 is that by dedicating the entire forming apparatus (e.g., apparatus 310b) to forming a portion of the central region, method 300 can achieve a higher central region basis weight than method 200. In contrast, method 200 relies on only portions of two separate forming apparatuses to aid in the formation of the central region.

[0121] Alternatives to the described method 300 are also within the scope of this disclosure. In a first alternative method 300, the first apparatus 310a may form only the bicomponent meltblown fiber 220, instead of forming both the bicomponent meltblown fiber 220 and the homogeneous meltblown fiber 221. Thus, in these embodiments, the first apparatus 310a will include extruders 214, 214” and a die 316 arranged on both sides (e.g., upstream and downstream) of the secondary airflow 234. The intermediate web structure 254 will contain only the bicomponent meltblown fiber 220 and the secondary fiber material 232. In at least some of these embodiments, the third apparatus 310c may be relative to... Figure 3 The implementation scheme is similarly improved because the apparatus 310c can form only the bicomponent meltblown fibers 220. Therefore, in this implementation, the material applied to the intermediate web structure 254' will consist only of the bicomponent meltblown fibers 220 and secondary fiber material 232. This alternative implementation may allow for more discrete control of the amount and basis weight of the bicomponent meltblown fibers 220 and 221 of the bicomponent meltblown fibers 220 and 221 forming the bicomponent meltblown fibers 103 and homogeneous meltblown fibers 105 of the web structure.

[0122] Process 200 or process 300 can be modified in another way to produce an alternative nonwoven web 100. According to some aspects of this disclosure, forming apparatuses 210a, 210b, or 310a-c can each be configured to form only bicomponent meltblown fibers 220, without any homogeneous meltblown fibers 221. In this way, process 200 or process 300 can be used to form a homogeneous, non-layered nonwoven web 100. This nonwoven web 100 can be similar to... Figure 1 The web 100 will not have homogeneous meltblown fibers 105, but will have bicomponent meltblown fibers 103 arranged in a relatively homogeneous manner throughout the thickness of the web 100 structure. This improved process is used to form the HE1-3 example webs described herein.

[0123] It should be understood that this disclosure is by no means limited to the embodiments described above. In an alternative embodiment, for example, a first meltblown die and a second meltblown die may be employed, extending substantially through the forming surface in a direction substantially transverse to the direction of movement of the forming surface. The dies may also be arranged substantially vertically, i.e., perpendicular to the forming surface, such that the resulting meltblown fibers are blown directly downwards onto the forming surface. This configuration is well known in the art and is described in more detail, for example, in the embodiments granted. Dunbar et al. U.S. Patent Application Publication No. 2007 / 0049153. Furthermore, although the above embodiments employ multiple meltblown dies to produce fibers of different sizes, a single die can also be used. An example of this process is, for example, in [the patent application published in...]. Lassig et al. The patent is disclosed in U.S. Patent No. 7,168,932, the entire contents of which are incorporated herein by reference for all purposes.

[0124] Ideally, the nonwoven fiber web 100 can be used as a wet wipe containing a liquid. The liquid can be any solution capable of being absorbed into the wet wipe substrate (e.g., web 100) and can include any suitable components that provide the desired wiping properties. For example, these components may include water, emollients, surfactants, fragrances, preservatives, chelating agents, pH buffers, or combinations thereof, as well as is well known to those skilled in the art. The liquid may also contain detergents, pharmaceuticals, and / or other active agents.

[0125] The amount of liquid contained in each wet wipe can vary depending on the type of material used to provide the wet wipe, the type of liquid used, the type of container used to store the wet wipe, and the intended end use of the wet wipe. Generally, based on the dry weight of the wipe, each wet wipe may contain about 150 to about 600% by weight, and preferably about 250 to about 450% by weight, of liquid to improve wiping. In one particular aspect, the amount of liquid contained in the wet wipe is about 300% to about 400% by weight based on the dry weight of the wet wipe. If the amount of liquid is less than the above range, the wet wipe may be too dry and not effective. If the amount of liquid is greater than the above range, the wet wipe may be oversaturated and damp, and the liquid may pool at the bottom of the container.

[0126] Each wet wipe can be generally rectangular in shape and can have any suitable unfolded width and length. For example, a wet wipe can have an unfolded length of about 2.0 cm to about 80.0 cm, and ideally about 10.0 cm to about 25.0 cm, and an unfolded width of about 2.0 cm to about 80.0 cm, and ideally about 10.0 cm to about 25.0 cm. Typically, each individual wet wipe is arranged in a folded configuration and one stacked on top of another, or is a continuous strip of material with perforations to provide a stack of wet wipes. The stacks of wet wipes can be placed inside a container such as a plastic drum and arranged in piles for distribution to provide wet wipe packaging for final sale to consumers.

[0127] The nonwoven web 100 of this disclosure can be used alternatively in a variety of articles. For example, the web 100 can be incorporated into "absorbent articles" capable of absorbing water or other fluids. Examples of absorbent articles include, but are not limited to, personal care absorbent articles such as diapers, training pants, absorbent underwear, incontinence articles, feminine hygiene products (e.g., sanitary napkins), swimwear, etc.; medical absorbent articles such as clothing, fenestration materials, pads, mattresses, bandages, absorbent drapes, and medical wipes; garment articles; pockets, etc. The materials and methods for forming such articles are well known to those skilled in the art. Several examples of such absorbent articles are granted in the grant DiPalma et al. U.S. Patent No. 5,649,916, granted Kielpikowski U.S. Patent No. 6,110,158 and granted Blaney et al. The descriptions are found in U.S. Patent No. 6,663,611, the entire contents of which are incorporated herein by reference for all purposes. Other suitable articles are also described in the patent granted. Fell et al. U.S. Patent Application Publication No. 2004 / 0060112 A1 and the grant Damico et al. U.S. Patent No. 4,886,512, granted Sherrod et al. U.S. Patent No. 5,558,659, granted Fell et al. U.S. Patent No. 6,888,044 and granted Freiburger, etc. people As described in U.S. Patent No. 6,511,465, all of which are incorporated herein by reference in their entirety for all purposes. When used in absorbent articles, the nonwoven web 100 of this disclosure may form the components of the absorbent core or any other absorbent component of absorbent articles well known in the art.

[0128] While the invention has been described in detail with reference to specific embodiments thereof, it will be appreciated that those skilled in the art, upon gaining an understanding of the foregoing, will readily conceive of alternative forms, variations, and equivalents of these embodiments. Therefore, the scope of the invention should be assessed as encompassing the appended claims and any of their equivalents. Furthermore, it should be noted that any given scope presented herein is intended to include any and all lesser-included scopes. For example, the scope of 45-90 also includes 50-90; 45-80; 46-89, etc.

[0129] CDT strength test method

[0130] The CDT strength test measures the peak load value, which is the maximum force generated by the sample when it is stretched to break. The sample is cut into 25 mm wide and 152 mm long pieces using a die-cutting machine or a sample cutter such as a JDC precision sample cutter (Thwing-Albert Instrument Company, Philadelphia, Pa., model JDC 3-10, serial number 37333). The sample is then treated at 23±2°C and 50±5% relative humidity for at least 4 hours before testing, and tested under the same environmental conditions. The length dimension of the sample should extend in the transverse direction of the cut sample web. The CDT strength value is the peak load at which the sample is stretched to break, measured in grams per force (gF). More specifically, the CDT strength value is the peak load when the sample is stretched by a force in a direction intersecting the longitudinal orientation of the sample.

[0131] The tensile strength tester is an MTS Standard 41 or 43 and an MTS TestSuite Elite™ (MTS Systems Corp., Research Triangle Park, NC). A load cell is selected such that the peak load value falls between 10% and 90% of the load cell's full-scale load—a load cell with a maximum load capacity of 50 or 100 Newtons is often appropriate, depending on the strength of the sample being tested. The gauge length is 76 mm, the jaw width is 76 mm, and the approximate height is 12.7 mm. The clamping speed is 305 mm / min, and the fracture sensitivity is set to 70%.

[0132] The sample was placed in the jaws of the instrument, centered vertically and horizontally, parallel to the direction of load application along its longer dimension. The clamps were pneumatically operated and coated with rubber. The test was then initiated and ended when the sample broke. The peak load was determined and reported as the CDT strength value of the sample, accurate to 0.1 gf. Five (5) representative samples were tested, and the arithmetic mean of all the individual samples tested is the tensile strength of the product.

[0133] TS7 Softness Test Method

[0134] The softness of nonwoven webs was measured using the EMTEC Tissue Softness Analyzer (“TSA”) (Emtec Electronic GmbH, Leipzig, Germany), specifically the TS7 value. The TSA comprises a rotor with vertical blades that rotate over a test specimen, thereby applying a defined contact pressure. The contact between the vertical blades and the test specimen generates vibrations, which are sensed by a vibration sensor. The sensor then transmits a signal to a personal computer (PC) for processing and display. The signal is displayed as a spectrum. To measure the TS7 value, the blades are pressed against the sample with a load of 100 mN, and the blades rotate at 2 revolutions per second.

[0135] To measure the TS7 value, frequency analysis was performed in the range of approximately 1 kHz to 10 kHz, and the peak amplitude appearing at 7 kHz was recorded as the TS7 value. The TS7 value represents the softness of the sample, and lower amplitudes are associated with softer samples. The unit of TS7 value is root mean square dB V² (rms).

[0136] Test samples were prepared by cutting circular samples with a diameter of 112.8 mm. All samples were equilibrated under TAPPI standard temperature and humidity conditions for at least 24 hours before completing the TSA test. The samples were placed in the TSA with the air side facing upwards (the sides of the samples collected on the forming line facing downwards). The samples were fixed, and measurements were initiated via the PC. The PC recorded, processed, and stored all data according to the standard TSA protocol. The reported value is the average of five repeated tests, each using a new sample.

[0137] Cup pressure test

[0138] As used herein, the term "cup crusher" refers to a measure of the softness of a nonwoven fabric sheet as determined by a cup crusher test. The cup crusher test evaluates the stiffness of a fabric by measuring the peak load (also known as "cup crusher load" or "cup crusher only") and the energy required to crush the sample, and thus quantifies the softness of the sample. Figure 7 and 8A pressure cup testing system 1100, including a cup forming assembly 1102, is shown. The system also includes a hemispherical pressure foot 1108 (formed from lightweight nylon or metal) with a diameter of 45 mm located at the free end of a rod 1105. Samples are prepared by cutting them into squares with sides of 178 mm, for example using a die-cutting machine or sample cutter such as a JDC precision sample cutter (Thwing-Albert Instrument Company, Philadelphia, Pa., model JDC 3-10, serial number 37333). Samples should be handled and tested in a standard laboratory atmosphere of 23 ± 2°C and 50 ± 5% relative humidity.

[0139] Component 1102 includes mating top-cap forming cups 1110 and 1112, which clamp sheet 1202 (e.g., a sample) at at least four points. Forming cup 1110 has a diameter of 65 mm and a height of 65 mm. To form component 1102, sheet 1202 is placed over forming cup 1112, with clamping rings positioned on forming cup 1112. Forming cup 1110 is placed over sheet 1202 and slowly slid down from forming cup 1112 to co-form sample 1112 into a cup shape. Forming cup 1110 is slid until ring 1114 contacts the four corners 1106 of sheet 1202, with sheet 1202 extending outside component 1102 and clamped between ring 1114 and cup 1110. After sheet 1202 is formed into a cup shape, cup 1112 is removed. There may be a gap between the ring 1114 and the forming cup 1110, but at least the four corners 1106 must be fixedly clamped therebetween.

[0140] The forming cup 1110 and the sheet 1202 held in the forming cup 1110 by the clamping ring 1114, along with the sample, are then placed on a load plate mounted on a tensile testing machine. The constant-speed elongation tensile testing machine can be an MTS Standard 42 equipped with a computerized data acquisition system (such as the MTS TestSuite Elite™, from MTS Systems Corp., Research TrianglePark, NC), which is capable of calculating peak load and energy, preferably at a minimum data acquisition rate of 20 data points per second, in compression mode between two predetermined distances (15-60 mm).

[0141] The presser foot 1108 and cup 1110 are aligned to avoid contact between the cup wall and the presser foot, which would affect the reading. The presser foot 1108 is positioned approximately 75 mm (e.g., gauge length) from the load plate. The chuck speed is set to 406.4 mm / min, and to capture data, the presser foot 1108 descends through the open end of the forming cup 1110 and “crushes” and twists the internal cup-shaped sheet 1202. The peak load from the start of travel of the presser foot 1108 to 60 mm, as measured by a tensile tester connected to the PC, is recorded in grams per second (gf), and the energy is measured in gf-length (gf-mm). The presser foot 1108 is set to travel at least 62 mm from the start to ensure data is captured at 60 mm. The result is a representation of material hardness. The harder the material, the higher the peak load and energy values. The softer the material, the lower these values.

[0142] Example Implementation Plan

[0143] Implementation Scheme 1: A nonwoven web material may comprise: a first outer region, the first outer region comprising: a first meltblown polymer fiber, the first meltblown polymer fiber comprising a first polymer component and a second polymer component, and absorbent fibers, wherein the content of the second polymer component of the first meltblown polymer fiber is greater than 0% by weight and less than or equal to 20% by weight of the total polymer content of the first meltblown polymer fiber; a second outer region, the second outer region comprising: a second meltblown polymer fiber, the second meltblown polymer fiber comprising a first polymer component and a second polymer component, and absorbent fibers, wherein the content of the second polymer component of the second meltblown polymer fiber is greater than 0% by weight and less than or equal to 20% by weight of the total polymer content of the second meltblown polymer fiber; and a central region disposed between the first outer region and the second outer region, the central region comprising: a third meltblown polymer fiber, the third meltblown polymer fiber being different from the first meltblown polymer fiber and the second meltblown polymer fiber, and not comprising the second polymer component, and absorbent fibers.

[0144] Implementation Scheme 2: The nonwoven web material as described in Implementation Scheme 1, wherein the second polymer component of the first meltblown polymer fiber and the second meltblown polymer fiber may be the same.

[0145] Implementation Scheme 3: The nonwoven web material as described in any one of Implementation Scheme 1 or 2, wherein the second polymer component of the first meltblown polymer fiber and the second polymer component of the second meltblown polymer fiber may be polyethylene.

[0146] Implementation Scheme 4: The nonwoven web material as described in any one of Implementation Schemes 1-3, wherein the third meltblown polymer fiber in the central region may comprise a single-component fiber.

[0147] Implementation Scheme 5: The nonwoven web material as described in Implementation Scheme 4, wherein the third meltblown fiber may be formed from the first polymer component.

[0148] Implementation Scheme 6: The nonwoven web material as described in any one of Implementation Schemes 1-5, wherein the first meltblown polymer fiber and the second meltblown polymer fiber comprise bicomponent meltblown fibers, and wherein the second polymer component substantially surrounds and covers the first polymer component of the bicomponent meltblown fibers.

[0149] Implementation Scheme 7: The nonwoven web material as described in any one of Implementation Schemes 1-6, wherein the first meltblown polymer fiber in the first outer region comprises a bicomponent polymer fiber formed of polypropylene and the second polymer component.

[0150] Implementation Scheme 8: The nonwoven web material as described in any one of Implementation Schemes 1-7, wherein the content of the second polymer component of the first meltblown polymer fiber is greater than 0% by weight and less than or equal to 15% by weight of the total polymer content of the first meltblown polymer fiber.

[0151] Implementation Scheme 9: The nonwoven web material as described in any one of Implementation Schemes 1-8, wherein the content of the second polymer component combination of the first meltblown polymer fiber and the second meltblown polymer fiber is greater than or equal to 0% by weight and less than or equal to 4% by weight of the total weight of the nonwoven web material.

[0152] Implementation Scheme 10: The nonwoven web material as described in Implementation Scheme 9, wherein the combined basis weight of the first meltblown polymer fiber is greater than or equal to 3% and less than or equal to 20% of the total basis weight of the nonwoven web material, and wherein the basis weight of the third meltblown polymer fiber is greater than or equal to 17% and less than or equal to 37% of the total basis weight of the nonwoven web material.

[0153] Implementation Scheme 11: The nonwoven web material as described in any one of Implementation Schemes 1-10, wherein the total basis weight of the nonwoven web material is greater than or equal to 45 gsm and less than or equal to 80 gsm, and wherein the basis weight of the central region is greater than or equal to 50% and less than or equal to 85% of the total basis weight of the nonwoven web material.

[0154] Implementation Scheme 12: A nonwoven web material as described in any one of Implementation Schemes 1-11, wherein the first outer region, the central region and the second outer region each comprise a separate co-forming layer, wherein the meltblown polymer fibers and the absorbent fibers are mixed together and then deposited onto a forming screen.

[0155] Implementation Scheme 13: A layered co-formed nonwoven web material of a certain thickness may include: a first outer region comprising a combination of meltblown polymer fibers and absorbent fibers; a second outer region comprising a combination of meltblown polymer fibers and absorbent fibers; and a central region disposed between the first outer region and the second outer region, the central region comprising a combination of meltblown polymer fibers and absorbent fibers, wherein at least some of the meltblown polymer fibers comprise bicomponent meltblown polymer fibers, and at least some of the meltblown polymer fibers comprise monocomponent meltblown polymer fibers, the bicomponent meltblown polymer fibers extending through a thickness less than the entire thickness of the layered co-formed nonwoven web.

[0156] Implementation Scheme 14: The layered co-formed nonwoven web material as described in Implementation Scheme 13, wherein the bicomponent meltblown polymer fiber comprises a first polymer component and a second polymer component, and wherein the second polymer component accounts for more than 0% by weight and less than or equal to 20% by weight of the total polymer content of the bicomponent meltblown polymer fiber.

[0157] Implementation Scheme 15: The layered co-formed nonwoven web material as described in Implementation Scheme 14, wherein the polyethylene content of the meltblown polymer fiber in the layered co-formed nonwoven web material is greater than 0% by weight and less than or equal to 3% by weight of the total weight of the layered co-formed nonwoven web material.

[0158] Implementation Scheme 16: A layered co-formed nonwoven web material as described in any one of Implementation Schemes 13-15, wherein the bicomponent meltblown polymer fiber comprises a first polymer component and a second polymer component, and wherein the second polymer component accounts for more than 0% by weight and less than or equal to 15% by weight of the total polymer content of the bicomponent meltblown polymer fiber.

[0159] Implementation Scheme 17: A layered co-formed nonwoven web material as described in any one of Implementation Schemes 13-16, wherein the meltblown polymer fibers in the first outer region and the second outer region comprise bicomponent polymer fibers, and wherein the meltblown polymer fibers in the inner region comprise monocomponent polymer fibers without any bicomponent polymer fibers.

[0160] Implementation Scheme 18: The layered co-formed nonwoven web material as described in Implementation Scheme 17, wherein the single-component polymer fibers in the inner region are formed of polypropylene.

[0161] Implementation Scheme 19: A layered co-formed nonwoven web material as described in any one of Implementation Schemes 14-18, wherein the bicomponent meltblown polymer fiber comprises a first polymer component of polyethylene and a second polymer component of polypropylene.

[0162] Implementation Scheme 20: A layered co-formed web material has a certain total basis weight and may include: a first co-formed outer region, the first co-formed outer region comprising: meltblown polymer fibers, the meltblown polymer fibers comprising bicomponent meltblown polymer fibers formed by a first polymer component and a second polymer component, the second polymer component being present in an amount greater than 0% and less than or equal to 3% of the total basis weight of the layered co-formed web material, and accounting for less than or equal to 40% of the total polymer content of the bicomponent meltblown polymer fibers in the first co-formed outer region, and absorbent fibers; a second co-formed outer region, the second co-formed outer region comprising: meltblown polymer fibers, the meltblown polymer fibers comprising bicomponent meltblown polymer fibers formed by a first polymer component and a second polymer component, and absorbent fibers; The material comprises: bicomponent meltblown polymer fibers formed from the polymer components, wherein the second polymer component is present in an amount greater than 0% and less than or equal to 3% of the total basis weight of the layered co-formed web material, and accounts for less than or equal to 40% of the total polymer content of the bicomponent meltblown polymer fibers in the second co-formed outer region; and absorbent fibers; and a central co-formed region disposed between the first co-formed outer region and the second co-formed outer region, wherein the basis weight of the central co-formed region is greater than or equal to 40% and less than or equal to 60% of the total basis weight of the layered co-formed web material, and the central co-formed region comprises: meltblown polymer fibers, wherein the meltblown polymer fibers comprise monocomponent meltblown polymer fibers; and absorbent fibers.

[0163] Implementation Scheme 21: The layered co-formed web material as described in Implementation Scheme 20, wherein in the first co-formed outer region, the second polymer component accounts for less than or equal to 20% of the total polymer content of the bicomponent meltblown polymer fibers in the first co-formed outer region, and wherein in the second co-formed outer region, the second polymer component accounts for less than 20% of the total polymer content of the bicomponent meltblown polymer fibers in the second co-formed outer region.

[0164] Implementation Scheme 22: A layered co-formed web material as described in any one of Implementation Schemes 20 or 21, wherein, in the first co-formed outer region and the second co-formed outer region, the first polymer component is polypropylene and the second polymer component is polyethylene.

[0165] Implementation Scheme 23: A layered co-formed web material as described in any one of Implementation Schemes 20-22, wherein the bicomponent meltblown polymer fiber has a core-sheath cross-sectional structure, wherein the second polymer component surrounds and covers the first polymer component.

[0166] Implementation Scheme 24: A layered co-formed web material as described in any one of Implementation Schemes 20-23, wherein the amount of meltblown polymer fibers present in the first outer region is greater than or equal to 25% and less than or equal to 40% of the total basis weight of the layered co-formed web material, and the amount of absorbent fibers present in the first outer region is greater than or equal to 60% and less than or equal to 75% of the total basis weight of the layered co-formed web material.

[0167] Implementation Scheme 25: A layered co-formed web material as described in any one of Implementation Schemes 20-24, wherein the layered co-formed web material has a TS7 softness value of less than or equal to 4.0 according to the TS7 softness test method and a CDT strength value of greater than or equal to 228 gf according to the CDT strength test method.

[0168] Implementation Scheme 26: The layered co-formed nonwoven web material as described in Implementation Scheme 25, wherein the cup-compression flexibility value of the layered co-formed web material is less than or equal to 1400 gf*mm.

[0169] Implementation Scheme 27: A nonwoven web material may comprise a first meltblown polymer fiber, the first meltblown polymer fiber comprising a first polymer component and a second polymer component; and absorbent fibers; wherein the first meltblown polymer fiber is distributed throughout the nonwoven web material arrangement; and wherein the content of the second polymer component of the first meltblown polymer fiber is greater than 0% by weight and less than or equal to 20% by weight of the total polymer content of the first meltblown polymer fiber.

[0170] Implementation Scheme 28: The nonwoven web material as described in Implementation Scheme 27, wherein the content of the second polymer component of the first meltblown polymer fiber is greater than or equal to 5% by weight and less than or equal to 15% by weight of the total polymer content of the first meltblown polymer fiber.

[0171] Implementation Scheme 29: The nonwoven web material as described in any one of Implementation Schemes 27 or 28, wherein the content of the second polymer component of the first meltblown polymer fiber is greater than or equal to 10% by weight and less than or equal to 20% by weight of the total polymer content of the first meltblown polymer fiber.

[0172] Implementation Scheme 30: A nonwoven web material as described in any one of Implementation Schemes 27-29, wherein the first meltblown polymer fiber comprises a bicomponent fiber, and wherein the bicomponent fiber has a core-sheath cross-sectional structure, wherein the second polymer component surrounds and covers the first polymer component.

[0173] Implementation Scheme 31: The nonwoven web material as described in any one of Implementation Schemes 27-30, the nonwoven web material further comprising a second meltblown polymer fiber, the second meltblown polymer fiber comprising a single-component fiber formed of the first polymer component or a third polymer component different from either the first polymer component or the second polymer component.

[0174] Implementation Scheme 32: The nonwoven web material as described in any one of Implementation Schemes 27-31, wherein the second polymer component of the first meltblown polymer fiber is polyethylene.

[0175] Implementation Scheme 33: The nonwoven web material as described in any one of Implementation Schemes 27-32, wherein the first meltblown polymer fiber comprises a bicomponent fiber formed of polypropylene and the second polymer component.

[0176] Implementation Scheme 34: The nonwoven web material as described in any one of Implementation Schemes 27-33, wherein the content of the second polymer component of the first meltblown polymer fiber is greater than or equal to 0% by weight and less than or equal to 8% by weight of the total weight of the nonwoven web material.

[0177] Implementation Scheme 35: The nonwoven web material as described in any one of Implementation Schemes 27-34, wherein the content of the second polymer component of the first meltblown polymer fiber is greater than or equal to 4% by weight and less than or equal to 8% by weight of the total weight of the nonwoven web material.

[0178] Implementation Scheme 36: A nonwoven web material as described in any one of Implementation Schemes 27-35, wherein the total basis weight of the nonwoven web material is between 45 gsm and 80 gsm, and wherein the basis weight of the first meltblown fiber is greater than or equal to 30% and less than or equal to 50% of the total basis weight of the nonwoven web.

[0179] Implementation Scheme 37: The nonwoven web material as described in any one of Implementation Schemes 27-36, wherein the amount of the first meltblown fiber is greater than or equal to 13 gsm and less than or equal to 40 gsm, and the amount of the absorbent fiber is greater than or equal to 23 gsm and less than or equal to 56 gsm.

[0180] Implementation Scheme 38: A nonwoven web material as described in any one of Implementation Schemes 27-37, wherein the nonwoven web material has a TS7 softness value of less than or equal to 4.0 according to the TS7 softness test method and a CDT strength value of greater than or equal to 237 gf according to the CDT strength test method.

[0181] Implementation Scheme 39: A nonwoven web material as described in any one of Implementation Schemes 27-38, wherein the nonwoven web material has a TS7 softness value of less than or equal to 4.0 according to the TS7 softness test method and a CDT strength value of greater than or equal to 237 gf and less than or equal to 347 gf according to the CDT strength test method.

[0182] Implementation Scheme 40: A nonwoven web material as described in any one of Implementation Schemes 27-39, wherein the nonwoven web material has a TS7 softness value of less than or equal to 4.66 and greater than or equal to 3.47 according to the TS7 softness test method and a CDT strength value of greater than or equal to 237 gf and less than or equal to 347 gf according to the CDT strength test method.

[0183] Implementation Scheme 41: A nonwoven web material as described in any one of Implementation Schemes 27-40, wherein the nonwoven web material has a TS7 softness value of less than or equal to 4.0 and greater than or equal to 3.47 according to the TS7 softness test method and a CDT strength value of greater than or equal to 237 gf and less than or equal to 325 gf according to the CDT strength test method.

[0184] Implementation Scheme 41: A method for forming a nonwoven web material may include merging a first stream of absorbent material with one or more first streams of meltblown polymer fibers to form a first composite stream, the one or more first streams of meltblown polymer fibers comprising bicomponent fibers formed of a first polymer component and a second polymer component; collecting the first composite stream onto a forming surface; merging a second stream of absorbent material with one or more second streams of meltblown polymer fibers to form a second composite stream, the one or more second streams of meltblown polymer fibers comprising bicomponent fibers formed of the first polymer component and the second polymer component; and collecting the second composite stream onto the collected first composite stream disposed on the forming surface, wherein the content of the second polymer component of the bicomponent fibers is greater than 0% by weight and less than or equal to 20% by weight of the total polymer content of the bicomponent fibers.

[0185] Implementation Scheme 42: The method as described in Implementation Scheme 41, wherein the total basis weight of the second polymer component in the nonwoven web material is greater than or equal to 2% and less than or equal to 15% of the total basis weight of the nonwoven web material.

[0186] Implementation Scheme 43: The method of any one of Implementation Schemes 41 or 42, wherein the total basis weight of the second polymer component in the nonwoven web material is greater than or equal to 4% and less than or equal to 10% of the total basis weight of the nonwoven web material.

[0187] Implementation Scheme 44: The method of any one of Implementation Schemes 41-43, wherein the total basis weight of the second polymer component in the nonwoven web material is greater than or equal to 4% and less than or equal to 8% of the total basis weight of the nonwoven web material.

[0188] Implementation Scheme 45: The method of any one of Implementation Schemes 42-44, wherein the basis weight of the meltblown fibers in the collected first composite stream is greater than or equal to 20% and less than or equal to 40% of the total basis weight of the collected first composite stream.

[0189] Implementation Scheme 46: The method of any one of Implementation Schemes 41-45, wherein the basis weight of the first composite stream collected is greater than or equal to 15% and less than or equal to 85% of the total basis weight of the nonwoven web material.

[0190] Implementation Scheme 47: The method of any one of Implementation Schemes 41-46, wherein the basis weight of the collected second composite stream is greater than or equal to 15% and less than or equal to 85% of the total basis weight of the nonwoven web material.

[0191] Implementation Scheme 48: The method of any one of Implementation Schemes 41-47, wherein the content of the second polymer component of the bicomponent fiber is greater than or equal to 5% by weight and less than or equal to 15% by weight of the total polymer content of the bicomponent fiber.

[0192] Implementation Scheme 49: The method of any one of Implementation Schemes 41-48, the method further comprising merging a third stream of absorbent material with one or more third streams of meltblown polymer fibers to form a third composite stream, the one or more third streams of meltblown polymer fibers comprising bicomponent fibers formed of the first polymer component and the second polymer component; and collecting the third composite stream onto a collected second composite stream disposed on the forming surface.

[0193] Implementation Scheme 50: The method as described in Implementation Scheme 49, wherein the basis weight of the meltblown polymer fibers in the first composite stream is greater than or equal to 2% and less than or equal to 15% of the total basis weight of the first composite stream, wherein the basis weight of the meltblown polymer fibers in the second composite stream is greater than or equal to 2% and less than or equal to 15% of the total basis weight of the first composite stream, and wherein the basis weight of the meltblown polymer fibers in the third composite stream is greater than or equal to 2% and less than or equal to 15% of the total basis weight of the first composite stream.

[0194] Implementation Scheme 51: The method of any one of Implementation Schemes 41-50, wherein the basis weight of the first composite stream collected is greater than or equal to 20% and less than or equal to 40% of the total basis weight of the nonwoven web material.

[0195] Implementation Scheme 52: The method of any one of Implementation Schemes 41-51, wherein the basis weight of the collected second composite stream is greater than or equal to 20% and less than or equal to 60% of the total basis weight of the nonwoven web material.

Claims

1. A nonwoven web material, the nonwoven web material comprising: A first outer region, the first outer region comprising: The first meltblown polymer fiber comprises a first polymer component and a second polymer component, and absorbent fibers The content of the second polymer component in the first meltblown polymer fiber is greater than 0% by weight and less than or equal to 20% by weight of the total polymer content of the first meltblown polymer fiber. The second outer region includes: The second meltblown polymer fiber comprises a first polymer component and a second polymer component, and absorbent fibers The content of the second polymer component in the second meltblown polymer fiber is greater than 0% by weight and less than or equal to 20% by weight of the total polymer content of the second meltblown polymer fiber; and A central region situated between the first outer region and the second outer region, the central region comprising: A third meltblown polymer fiber, which differs from the first and second meltblown polymer fibers and does not contain the second polymer component, and Absorbent fibers; in, In the first outer region and the second outer region, the first polymer component is polypropylene and the second polymer component is polyethylene.

2. The nonwoven web material of claim 1, wherein the third meltblown polymer fiber in the central region comprises a single-component fiber.

3. The nonwoven web material of claim 2, wherein the third meltblown polymer fiber is formed from the first polymer component.

4. The nonwoven web material of claim 1, wherein the first meltblown polymer fiber and the second meltblown polymer fiber comprise bicomponent meltblown fibers, and wherein the second polymer component surrounds and covers the first polymer component of the bicomponent meltblown fibers.

5. The nonwoven web material as claimed in claim 1, wherein the content of the second polymer component in the first meltblown polymer fiber is greater than 0% by weight and less than or equal to 15% by weight of the total polymer content of the first meltblown polymer fiber.

6. The nonwoven web material as claimed in claim 1, wherein the combined content of the second polymer component of the first meltblown polymer fiber and the second meltblown polymer fiber is greater than or equal to 0% by weight and less than or equal to 4% by weight of the total weight of the nonwoven web material.

7. The nonwoven web material of claim 6, wherein the combined basis weight of the first meltblown polymer fiber is greater than or equal to 3% and less than or equal to 20% of the total basis weight of the nonwoven web material, and wherein the basis weight of the third meltblown polymer fiber is greater than or equal to 17% and less than or equal to 37% of the total basis weight of the nonwoven web material.

8. The nonwoven web material as claimed in claim 1, wherein the total basis weight of the nonwoven web material is greater than or equal to 45 gsm and less than or equal to 80 gsm, and wherein the basis weight of the central region is greater than or equal to 50% and less than or equal to 85% of the total basis weight of the nonwoven web material.

9. The nonwoven web material of claim 1, wherein the first outer region, the central region and the second outer region each comprise a separate co-forming layer, wherein the meltblown polymer fibers and the absorbent fibers are mixed together and then deposited onto a forming screen.

10. A layered co-formed nonwoven web material having a certain thickness, the layered co-formed nonwoven web material comprising: A first outer region, the first outer region comprising a combination of meltblown polymer fibers and absorbent fibers; The second outer region comprises a combination of meltblown polymer fibers and absorbent fibers; and A central region is located between the first outer region and the second outer region, the central region comprising a combination of meltblown polymer fibers and absorbent fibers. The meltblown polymer fibers in the first and second outer regions comprise bicomponent polymer fibers, and the meltblown polymer fibers in the central region comprise monocomponent polymer fibers without any bicomponent polymer fibers, the bicomponent meltblown polymer fibers extending through a thickness less than the entire thickness of the layered co-formed nonwoven web. The bicomponent meltblown polymer fiber comprises a first polymer component and a second polymer component, wherein the second polymer component accounts for a percentage of the total polymer content of the bicomponent meltblown polymer fiber that is greater than 0% by weight and less than or equal to 20% by weight. The bicomponent meltblown polymer fiber comprises a first polymer component of polypropylene and a second polymer component of polyethylene.

11. The layered co-formed nonwoven web material of claim 10, wherein the polyethylene content of the meltblown polymer fiber of the layered co-formed nonwoven web material is greater than 0% by weight and less than or equal to 3% by weight of the total weight of the layered co-formed nonwoven web material.

12. The layered co-formed nonwoven web material of claim 10, wherein the second polymer component accounts for more than 0% by weight and less than or equal to 15% by weight of the total polymer content of the two-component meltblown polymer fiber.

13. The layered co-formed nonwoven web material of claim 10, wherein the single-component polymer fiber in the central region is formed of polypropylene.

14. A layered co-formed web material, said layered co-formed web material having a certain total basis weight and comprising: A first co-formed outer region, the first co-formed outer region comprising: The meltblown polymer fiber comprises a two-component meltblown polymer fiber formed from a first polymer component and a second polymer component, wherein the second polymer component is present in an amount greater than 0% and less than or equal to 3% of the total basis weight of the layered co-formed web material, and accounts for less than or equal to 20% of the total polymer content of the two-component meltblown polymer fiber in the outer region of the first co-formed web. Absorbent fibers; The second co-formed outer region includes: The meltblown polymer fiber comprises a two-component meltblown polymer fiber formed from a first polymer component and a second polymer component, wherein the second polymer component is present in an amount greater than 0% and less than or equal to 3% of the total basis weight of the layered co-formed web material, and accounts for less than or equal to 20% of the total polymer content of the two-component meltblown polymer fiber in the second co-formed outer region. Absorbent fibers; as well as A central co-forming region is located between the first co-forming outer region and the second co-forming outer region. The basis weight of the central co-forming region is greater than or equal to 40% and less than or equal to 60% of the total basis weight of the layered co-forming web material, and the central co-forming region comprises: Meltblown polymer fibers, the meltblown polymer fibers comprising single-component meltblown polymer fibers, and Absorbent fibers; In the first co-forming outer region and the second co-forming outer region, the first polymer component is polypropylene and the second polymer component is polyethylene.

15. The layered co-formed web material of claim 14, wherein the bicomponent meltblown polymer fiber has a core-sheath cross-sectional structure, wherein the second polymer component surrounds and covers the first polymer component.

16. The layered co-formed web material of claim 14, wherein the amount of meltblown polymer fibers present in the first co-formed outer region is greater than or equal to 25% and less than or equal to 40% of the total basis weight of the layered co-formed web material, and the amount of absorbent fibers present in the first co-formed outer region is greater than or equal to 60% and less than or equal to 75% of the total basis weight of the layered co-formed web material.

17. The layered co-formed web material of claim 14, wherein the layered co-formed web material has a TS7 softness value of less than or equal to 4.0 according to the TS7 softness test method and a CDT strength value of greater than or equal to 228 gf according to the CDT strength test method.

18. The layered co-formed web material as claimed in claim 17, wherein the cup flexibility value of the layered co-formed web material is less than or equal to 1400 gf*mm.

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