Nonwoven material with high strength and soft touch and laminates made therefrom

Abstract

A nonwoven fabric with an excellent balance between strength and softness is disclosed. The nonwoven material may be made from spunbonded layers and include at least one strength-building layer in combination with at least one softness-enhancing layer. In one aspect, the nonwoven material may be incorporated into an elastic laminate for use in absorbent articles.

Description

RELATED APPLICATIONS

[0001] This application is based upon and claims priority from U.S. Provisional Patent Application Serial No. 63 / 411,768, filed September 30, 2022, which is incorporated herein by reference in its entirety. BACKGROUND

[0002] Spunbonded nonwoven fabrics consist of bonded webs of continuous filaments formed by extruding a molten thermoplastic polymer from a plurality of fine capillaries as molten filaments. The molten filaments are quenched to at least partially solidify them and then attenuated by one or more high-velocity air streams that reduce their diameter. Filament spunbonded webs and methods for their manufacture are disclosed, for example, in US4340563 to Appel et al., US5382400 to Pike et al., US8246898 to Conrad et al., and US8333918 to Lennon et al.

[0003] Spunbonded filament webs are commonly used in a wide range of products. The reason for this extensive and diverse use is, in part, their ability to provide a desired combination of properties. Furthermore, the cost of producing spunbonded filament webs is relatively low compared to other materials with similar properties, such as traditional knitted or woven fabrics. As a result, spunbonded filament webs have proven particularly useful for the production of disposable or limited-use products, such as absorbent personal care products, wipes, protective clothing, geotextiles, tarpaulins, etc.

[0004] The properties of spunbonded webs can be varied by altering the polymer composition used to manufacture the web. For example, manufacturing spunbonded webs from elastomeric materials can result in webs with a soft hand and excellent masking properties. However, elastic spunbonded webs tend to lack strength and durability compared to spunbonded webs made from other polymer materials.

[0005] Given this, there is a need for a nonwoven web that not only exhibits a soft hand feel but also excellent strength properties. Furthermore, there is a need for an elastic laminate that can incorporate a nonwoven web as described above. OVERVIEW

[0006] In general, the present disclosure relates to the production of nonwoven webs with a good balance of softness and strength. In one aspect, for example, nonwoven webs according to the present disclosure are produced with a cover layer made of a soft, elastic spunbonded web. The nonwoven web further includes at least one additional strength-providing layer, which may also be made of a spunbonded web. In one embodiment, the strength-providing layer may be made of a fine fiber polymer layer. The nonwoven web is particularly well suited for producing elastic laminates in which the strength-providing layer is adjacent to an elastic film, the elastic layer forming a top layer of the laminate having soft, cloth-like properties.

[0007] For example, in one embodiment, the present disclosure relates to a nonwoven material. The nonwoven material includes a strength-forming layer comprising spunbond fibers randomly arranged to form a web. The spunbond fibers have a denier of less than about 2 and are made from a non-elastomeric polymer. For example, the non-elastomeric polymer may be a polypropylene polymer and comprise at least about 70%, such as at least about 80%, such as at least about 90%, of the strength-forming layer. The denier of the spunbond fibers included in the strength-forming layer may be less than about 1.5, such as less than about 1.3, such as less than about 1, such as less than about 0.9, such as less than about 0.85.

[0008] The nonwoven material further includes a softness-enhancing layer comprising spunbonded fibers randomly arranged to form a web. The softness-enhancing layer may be incorporated into the nonwoven material to form a top layer of the material. In one aspect, the softness-enhancing layer may be bonded to the strength-providing layer. The spunbonded fibers in the softness-enhancing layer may comprise elastomeric fibers. For example, the elastomeric fibers may consist of elastomeric bicomponent fibers including a core surrounded by a sheath. The core of the bicomponent fibers, in one embodiment, may be formed from a polypropylene-based elastomer alone or in combination with a secondary amide. The polypropylene-based elastomer may comprise an ethylene copolymer, an α-olefin copolymer, or a combination thereof. The sheath, however, may be formed from a non-elastomeric polymer.For example, the sheath can be made of a polyethylene polymer.

[0009] As described above, the core may contain a secondary amide, which may be a fatty acid amide. The secondary amide may, for example, have a chemical structure as follows:where R 14 , R 15 , R 16 and R 18 independently from C 7 -C 27 -alkyl groups and C 7 -C 27 -alkenyl groups are selected; and R 17 from C 8 -C 28 -alkyl groups and C 8 -C 28 -alkenyl groups is selected.

[0010] In one aspect, the elastomeric bicomponent fibers of the softness-enhancing layer may include a core of at least two elastomeric polymers alone or in combination with a secondary amide.

[0011] The basis weight of the nonwoven material produced according to the present disclosure may vary depending on the application and the desired result. In general, the basis weight of the nonwoven material may be between about 5 g / m 2 and about 300 g / m 2 including all increments of 1 g / m 2 In certain embodiments, the basis weight of about 5 g / m 2 up to about 170 g / m 2 , such as about 9 g / m 2 up to about 20 g / m 2 The weight ratio between the strength-building layer and the softness-enhancing layer within the nonwoven material may be about 1:3 to about 1.5:1, such as about 1:2 to about 1.1:1.

[0012] The present disclosure also relates to an elastomeric laminate containing the nonwoven material as described above. In one aspect, the elastomeric laminate may include an elastic backing, which may be comprised of an elastic film or a plurality of parallel elastic filaments or ribbons. In one aspect, the strength-providing layer may be adhered to the backing. The softness-enhancing layer, however, may form an outer surface of the elastomeric laminate.

[0013] Elastomeric laminates prepared according to the present disclosure can exhibit an excellent balance of strength and softness properties. For example, the elastomeric laminate can exhibit a burst strength of greater than about 1800 g, such as greater than about 2200 g, such as greater than about 2500 g, such as greater than about 2800 g, such as greater than about 3000 g, at a basis weight of about 20 g / m 2up to about 40 g / m 2 The laminate may have an average yield strength in a machine direction of greater than about 170%, such as greater than about 175%, and generally less than about 225% at a 2000 g load. In addition to the above properties, the laminate may also have excellent softness properties. For example, the TS7 of the laminate may be less than about 6, such as less than about 5.8, such as less than about 5.5, and generally greater than 2.

[0014] Further features and aspects of the present disclosure are described in more detail below. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] A complete and enabling disclosure of the present disclosure is more particularly described in the remainder of the specification, including reference to the accompanying figures, in which: Fig. 1a and Fig. 1b are exemplary fibers for use in nonwoven materials made according to the present disclosure; Fig. 2 is an exemplary schematic representation of an apparatus for forming a stretchable cover layer; Fig. 3 is an exemplary schematic representation of an apparatus for forming a strength-forming layer; Fig. 4 is an exemplary schematic representation of an apparatus for forming a nonwoven material according to the present disclosure; Fig. 5 is an exemplary schematic representation of an apparatus for forming elastic laminates according to the present disclosure; and Fig. 6 is an exemplary cross-sectional view of an elastic laminate that may be made in accordance with the present disclosure.

[0016] The repeated use of reference numerals in this specification and the drawings is intended to represent the same or analogous features or elements of the present invention. DEFINITIONS

[0017] As used herein, the terms "about," "approximately," or "generally," when used to modify a value, mean that the value may be increased or decreased by 10%, such as 7.5%, 5%, such as 4%, such as 3%, such as 2%, such as 1%, and remain within the disclosed aspect. Furthermore, the term "substantially free of," when used to describe the amount of a substance in a material, is not limited to "completely or totally free of," but can also correspond to the absence of any appreciable or detectable amount of said substance in the material. Thus, for example, a material is "substantially free of" a substance if the amount of the substance in the material is less than the accuracy of an industry-recognized instrument or test for measuring the amount of the substance in the material.In certain exemplary embodiments, a material may be "substantially free of" a substance if the amount of the substance in the material is less than 10%, less than 9%, less than 8%, less than 7%, less than 6%, less than 5%, less than 4%, less than 3%, less than 2%, less than 1%, less than 0.5%, or less than 0.1%, by weight of the material.

[0018] As used herein, the terms "elastomeric" and "elastic" refer to a material that is extensible in at least one direction (such as the CD or MD direction) upon application of a stretching force and that contracts / recovers approximately to its original dimension upon removal of the stretching force. For example, a stretched material may have a stretched length that is at least 50% greater than the relaxed, unstretched length and that recovers to at least 50% of the stretched length upon removal of the stretching force. A hypothetical example would be a one (1) inch sample of a material that can be stretched to at least 1.50 inches and that recovers to a length no greater than 1.25 inches upon removal of the stretching force. Preferably, the material contracts or recovers to at least 50%, and more preferably, to at least 80% of the stretched length.

[0019] As used herein, the term "fibers" generally refers to elongated extrudates that can be formed by passing a polymer through a forming orifice, such as a die. Unless otherwise noted, the term "fibers" includes discontinuous fibers having a definite length (e.g., stable fibers) and substantially continuous filaments. Substantially continuous filaments, for example, can have a length much greater than their diameter, such as a length-to-diameter ratio ("aspect ratio") of greater than about 15,000 to 1, and in some cases, greater than about 50,000 to 1.

[0020] As used herein, the term "extensible" generally refers to a material that stretches in the direction of an applied force (e.g., CD or MD direction) by about 50% or more, in some aspects by about 75% or more, in some aspects by about 100% or more, and in some aspects by about 200% or more of its relaxed length or width.

[0021] As used herein, the terms "necked" and "necked material" generally refer to any material that has been drawn in at least one dimension (e.g., in the machine direction) to reduce its transverse dimension (e.g., in the cross-machine direction) so that the material can be retracted to its original width after the drawing force is released. The necked material generally has a higher basis weight per unit area than the unnecked material. When the necked material is drawn back to its original width, it should have approximately the same basis weight as the unnecked material. This is different from the orientation of a film, in which the film is thinned and the basis weight is reduced.The necking process typically involves unwinding the material from a supply roll and passing it through a brake nip roll assembly driven at a specific linear speed. A take-up roll or nip, operating at a higher linear speed than the brake nip roll, pulls the material and creates the necessary tension to stretch and neck the material.

[0022] As used herein, the term "nonwoven web" generally refers to a web having a structure of individual fibers or filaments interwoven, but not in an identifiable manner as in a knit fabric. Examples of suitable nonwoven fabrics or webs include, but are not limited to, meltblown webs, spunbonded webs, bonded carded webs, airlaid webs, coform webs, hydraulically entangled webs, and so on.

[0023] As used herein, the term "meltblown web" generally refers to a nonwoven web formed by a process in which a molten thermoplastic material is extruded through a plurality of fine, usually circular, die capillaries as molten fibers into converging high-velocity gas streams (e.g., air streams) that attenuate fibers of molten thermoplastic material to reduce their diameter, which may be a microfiber diameter. Thereafter, the meltblown fibers are entrained by the high-velocity gas stream and deposited on a collecting surface to form a web of randomly distributed meltblown fibers. Such a process is disclosed, for example, in U.S. Patent No. 3,849,241 to Butin et al., which is incorporated herein by reference in its entirety for all purposes.Generally speaking, meltblown fibers may be microfibers that may be essentially continuous or discontinuous, that generally have a diameter less than 10 microns, and that are generally sticky when deposited on a collecting surface.

[0024] As used herein, the term "spunbonded web" generally refers to a web containing essentially continuous, small-diameter fibers. The fibers are formed by extruding molten thermoplastic material from a plurality of fine, usually round, capillaries from a spinneret, with the diameter of the extruded fibers then being rapidly reduced, for example, by eductive drawing and / or other known spunbond mechanisms. The production of spunbonded webs is described and illustrated, for example, in U.S. Patent Nos. 4,340,563 to Appel, et al., 3,692,618 to Dorschner, et al., 3,802,817 to Matsuki, et al., 3,338,992 to Kinney, 3,341,394 to Kinney, 3,502,763 to Hartman, 3,502,538 to Levy, 3,542,615 to Dobo, et al., and 5,382,400 to Pike, et al., all of which are incorporated herein by reference for all purposes.Spunbond fibers are generally non-sticky when deposited on a collecting surface. Spunbond fibers can sometimes have diameters of less than about 40 microns and often range from about 5 to about 20 microns.

[0025] As used herein, the term "machine direction" or "MD" generally refers to the direction in which a material is manufactured (e.g., the direction in which the material is conveyed during the nonwoven material forming / manufacturing process). The term "cross-machine direction" or "CD" refers to the direction perpendicular to the machine direction.

[0026] As used herein, the term "thermal point bonding" generally refers to a process in which a material is passed between, for example, a patterned roll (e.g., a calender roll) and another roll (e.g., anvil roll), which may or may not be patterned. Typically, one or both of the rolls are heated.

[0027] As used herein, the term "ultrasonic bonding" generally refers to a process accomplished, for example, by passing a material between a sonotrode and a patterned roll (e.g., anvil roll). Ultrasonic bonding using a stationary sonotrode and a rotating patterned anvil roll is described, for example, in U.S. Patent Nos. 3,939,033 to Grgach, et al., 3,844,869 to Rust Jr., and 4,259,399 to Hill, each of which is incorporated in its entirety by reference for all purposes. In addition, ultrasonic bonding using a rotating sonotrode with a rotating anvil roll is described in U.S. Patent Nos. 5,096,532 to Neuwirth, et al., 5,110,403 to Ehlert, and 5,817,199 to Brennecke, et al. described, each of which is incorporated herein by reference in its entirety for all purposes.Of course, any other ultrasonic bonding technique may be used in the present disclosure.

[0028] As used herein, “continuous filaments” means filaments that are formed substantially continuously and uninterruptedly, of indefinite length, and with a high aspect ratio (length to diameter) of greater than about 10,000:1.

[0029] As used herein, the term "polymer" generally includes, but is not limited to, homopolymers, copolymers, such as block, graft, random, and alternating copolymers, terpolymers, etc., as well as their blends and modifications. Furthermore, unless expressly limited otherwise, the term "polymer" includes all possible geometric configurations of the molecule. These configurations include, but are not limited to, isotactic, syndiotactic, and random symmetries.

[0030] As used herein, “ethylene polymer” or “polyethylene” means a polymer having more than 50 mole percent of units derived from ethylene.

[0031] As used herein, “olefin polymer” or “polyolefin polymer” means a polymer having more than 50 mole percent units derived from an alkene, including linear, branched, or cyclic alkenes.

[0032] As used herein, “propylene polymer” or “polypropylene” means a polymer having more than 50 mole percent units derived from propylene.

[0033] As used herein, "personal care article" means any article or product used for personal health or hygiene, including diapers, adult incontinence garments, absorbent pants and garments, tampons, sanitary napkins and panty liners, wipes (e.g., baby wipes, perineal wipes, hand wipes, etc.), bibs, changing pads, bandages, and components thereof.

[0034] As used herein, “protective article” means any article designed to protect a user or equipment from contact with or exposure to external substances, including, for example, face masks, protective gowns and aprons, gloves, caps, shoe covers, equipment covers, sterile wraps (e.g., for medical instruments), car covers, etc. DETAILED DESCRIPTION

[0035] Those skilled in the art will understand that the present discussion is only a description of exemplary embodiments and is not intended to limit the broader aspects of the present disclosure.

[0036] In general, the present disclosure relates to a nonwoven material having at least two different layers. The layers include at least one strength-providing layer in combination with at least one softness-enhancing layer. The strength-providing layer may, for example, be composed of a non-elastomeric polymer having relatively fine fibers. The softness-enhancing layer, however, may be composed of one or more elastomeric materials. The nonwoven material of the present disclosure has numerous uses and applications. In one aspect, for example, the nonwoven material may be combined to form laminates or attached to an elastic backing.

[0037] Nonwoven materials produced according to the present disclosure offer various advantages and benefits. For example, nonwoven materials are relatively strong due to the strength-enhancing layer. Additionally, at least one outer layer of the nonwoven material includes the softness-enhancing layer, which has a noticeably soft feel. Thus, nonwoven materials produced according to the present disclosure exhibit a distinct balance between strength and softness. Softness-enhancing layer

[0038] As described above, the nonwoven material of the present disclosure generally includes at least one softness-enhancing layer and at least one strength-providing layer. The softness-enhancing layer forms a top or outer surface of the nonwoven material. The softness-enhancing layer has a soft feel and can be formulated into a sheet-like shape.

[0039] As described in more detail below, the polymers used to form the softening layer typically have a softening temperature higher than the temperature experienced during bonding and are extensible or elastomeric. Thus, the polymers do not soften so much during bonding that the fibers of the softening layers become fully melt-flowable. For example, polymers having a Vicat softening temperature (ASTM D-1525) of about 100°C to about 300°C, in some embodiments from about 120°C to about 250°C, and in some embodiments from about 130°C to about 200°C may be used. Examples of high softening point polymers for use in forming softening layers include ExxonMobil™ PP3155 (inelastic) and Achieve™ Advanced PP3854, as well as Dow™ ASPUN 6850.

[0040] Extensible or elastomeric monocomponent and / or multicomponent fibers can be used to form the softness-enhancing layers, e.g., the cover layer. Monocomponent fibers are generally formed from a polymer or a blend of polymers extruded from a single extruder. Multicomponent fibers are generally formed from two or more polymers (e.g., bicomponent fibers) extruded from separate extruders. The polymers can be arranged in substantially constantly positioned discrete zones across the cross-section of the fibers. The components can be arranged in any desired configuration, such as sheath-core, side-by-side, pie-shaped, island-in-the-sea, three islands, porthole, or various other arrangements known in the art, and so on. Various methods for forming multicomponent fibers are described in U.S. Pat. No. 4,789,592 to Taniguchi et al. and U.S. Pat.No. 5,336,552 to Strack et al., U.S. Pat. No. 5,108,820 to Kaneko, et al., U.S. Pat. No. 4,795,668 to Kruege, et al., U.S. Pat. No. 5,382,400 to Pike, et al., U.S. Pat. No. 5,336,552 to Strack, et al., and U.S. Pat. No. 6,200,669 to Marmon, et al., all of which are incorporated herein by reference for all purposes.

[0041] In some implementations, the polymers of the multicomponent fibers of the softness-enhancing layer are spunbonded fibers made of thermoplastic materials with different glass transition or melting temperatures, where a first component (e.g., the sheath) melts at a lower temperature than a second component (e.g., the core). Softening or melting the first polymer component of the multicomponent fiber allows the multicomponent fibers to form a sticky skeletal structure that, upon cooling, stabilizes the fibrous structure. For example, the multicomponent fibers may comprise from about 20% to about 80%, and in some embodiments, from about 40% to about 60%, by weight of the low-melting-point polymer. Furthermore, the multicomponent fibers may comprise from about 80% to about 20%, and in some embodiments, from about 60% to about 40%, by weight of the high-melting-point polymer.In some implementations, the core of the sheath-core bicomponent fibers includes a polypropylene homopolymer or copolymer based on either Ziegler-Natta catalysts or single-site catalysts and / or the sheath of the sheath-core bicomponent fibers includes homopolymers, copolymers, or blends thereof of ethylene, propylene, or styrene-derived polymers.

[0042] The basis weight of the softness-enhancing layer can generally be, for example, about 5 grams per square meter (“g / m 2 “) up to 200 g / m 2 , in some embodiments of about 6 g / m 2 up to about 70 g / m 2 and in some embodiments of about 8 g / m 2 up to about 35 g / m 2 vary. In one aspect, the basis weight is less than about 30 g / m 2 , such as less than about 25 g / m 2 , such as less than about 20 g / m 2 , such as less than about 15 g / m2 , such as less than about 12 g / m 2 , such as less than about 10 g / m 2 , such as less than about 9 g / m 2 , such as less than about 8 g / m 2 , such as less than about 7 g / m 2 and greater than about 4 g / m 2 In some embodiments, the nonwoven material of the present disclosure may include multiple softness-enhancing layers. For example, the softness-enhancing layers may be adjacent to one another within the nonwoven material, and each softness-enhancing layer may have the same basis weight or a different basis weight.

[0043] As described above, in some implementations, the nonwoven web is made from monocomponent spunbond fibers. In other implementations, the nonwoven web is made from bicomponent spunbond fibers. In these implementations, the bicomponent fiber includes, for example, a polyethylene sheath and a polypropylene-based elastomeric core. The core (but not the sheath) may contain a secondary amide as a non-blocking additive, which can further enhance the cloth-like feel of the topsheet.

[0044] In one aspect, the secondary amide additive is, for example, erucamide, oleamide, oleyl palmitamide, ethylenebisoleamide, stearyl erucamide, or combinations thereof. Of course, the secondary amide can also be a non-fatty acid amide.

[0045] Regardless of the secondary amide selected, in one aspect, the secondary amide is present in the core in an amount of from about 0.1 to about 10 wt. %, based on the weight of the core, such as from about 0.25 to about 5%, such as from about 0.5 to about 2.5%, such as from about 0.6 to about 1.5%, such as from about 0.7 to about 1%, or any ranges or values ​​therebetween. In particular, the present disclosure has shown that the secondary amide in the core surprisingly provides improved spinnability and non-blocking properties for the bicomponent fiber, even when used in low amounts in the core.

[0046] Furthermore, the sheath(s) is(are) formed from one or more ethylene or propylene polymers, such as one or more generally non-elastomeric ethylene or propylene polymers. In one aspect, the non-elastic polyolefin may therefore include generally inelastic polymers such as conventional polyolefins (e.g., polyethylene), low-density polyethylene (LDPE), Ziegler-Natta-catalyzed linear low-density polyethylene (LLDPE), etc., ultra-low-density polyethylene (ULDPE), polypropylene, polybutylene, etc.; polytetrafluoroethylene; polyesters, e.g., polyethylene terephthalate (PET), etc.; polyvinyl acetate; polyvinyl chloride acetate; polyvinyl butyral; acrylic resins, e.g., polyacrylate, polymethyl acrylate, polymethyl methacrylate, etc.; polyamides, e.g., nylon; polyvinyl chloride; polyvinylidene chloride; polystyrene; polyvinyl alcohol; polyurethanes; polylactic acid; copolymers and blends thereof; and so on. For example, the coat orThe jackets may include an LLDPE available from Dow Chemical Co. of Midland, Michigan, such as DOWLEX™ 2517 or DOWLEX™ 2047, or a combination thereof, or from Westlake Chemical Corp. of Houston, Texas. In addition, the non-blocking polyolefin material may be other suitable ethylene polymers, such as those available from The Dow Chemical Company under the designations ASPUNTM (LLDPE) and ATTANE™ (ULDPE), or from The Dow Chemical Company under the designations DOWLEX™ (LLDPE), ASPUNTM (LLDPE), and ATTANE™ (ULDPE).

[0047] In another aspect, the core is formed from a propylene polymer and / or copolymer. Thus, in one aspect, the core is formed from a propylene-based copolymer plastomer, such as a propylene-based copolymer commercially available under the designations VISTAMAXX™ (e.g., 2330, 6202, and 6102), a propylene-ethylene copolymer-based plastomer, from ExxonMobil Chemical Co. of Houston, Texas; FINA™ (e.g., 8573) from Atofina Chemicals of Feluy, Belgium; TAFMER™, available from Mitsui Petrochemical Industries; and VERSIFY™, available from Dow Chemical Co. of Midland, Michigan. Additionally, the core may also contain a non-elastomeric olefin polymer, such as a metallocene-catalyzed (single-site catalyzed) polypropylene polymer in an amount of about 1 wt.% to about 40 wt.% of the core, such as about 2 wt.% to about 5 wt.% of the core.

[0048] Regardless of the elastomer(s) and non-elastomeric polyolefins selected, in one aspect the core is present in an amount of from about 50 to about 97.5 wt.% of the total weight of the elastomer composition, such as from about 60 to about 95%, such as from about 70 to about 92.5%, such as from about 80 to about 90 wt.%, such as from about 82.5 to about 87.5 wt.% of the total weight of the elastomer composition, or any ranges or values ​​therebetween.

[0049] With reference to Fig.1A and 1B, respectively, a monocomponent fiber 12 and a bicomponent fiber 14 are shown utilizing a sheath / core arrangement. With respect to the bicomponent fiber 14, the core 18 may be formed from a first polymer, while the sheath 16 may be formed from a second polymer. In general, the composition of the monocomponent fiber 12 or the core 18 of the bicomponent fiber can be selected such that the resulting overall material is elastic, cloth-like, drapable, and soft, and the composition of the sheath 16 of the bicomponent fiber 14 can be selected such that the sheath 16 provides some blocking properties without compromising the cloth-like feel of the sheath 16. An example of such a bicomponent fiber suitable for use in the softness-enhancing layer is described in U.S. Patent Application Serial No. 63 / 003427, filed on June 1, 1997, the entire contents of which is incorporated herein by reference.April 2020 entitled “Elastic Bicomponent Fiber Having Unique Handfeel,” the entire contents of which are hereby incorporated by reference, including, without limitation, the composition of the claimed elastomeric bicomponent spunbonded fiber and the web formed from that fiber.

[0050] Fig. Figure 2 shows an exemplary process for forming elastomeric, monocomponent or bicomponent spunbond fibers. In particular, the Fig.2 are designed to form substantially continuous fibers (e.g., to produce a stretchable or elastomeric layer 30). Specifically, in the case of a bicomponent fiber, different polymer compositions A (e.g., for the sheath) and B (for the core) are first fed to a fiber spinning device 21 to form bicomponent fibers 23. Or, in the case of a monocomponent fiber, only one type of polymer (which may, for example, include a copolymer with or without additives) is fed to a fiber spinning device 21. Once formed, the fibers 23 are passed through a fiber drawing unit 25 and deposited onto a movable forming screen 27. The deposition of the fibers is assisted by a vacuum beneath the screen provided by a suction box 29, which draws the fibers 23 onto the forming screen 27.The forming wire 27 is porous, so that the vertical airflow created by the suction box 29 can cause the fibers to lay down. In one aspect of the present disclosure, the flow velocity of this airflow can be kept relatively low to enhance the tendency of the fibers 23 to remain aligned in the MD direction. Alternatively, the suction box 29 can include sections extending in the MD direction to interrupt the vertical airflow at the point where the fibers are laid down on the moving web, allowing the fibers a higher degree of MD alignment. An example of such a technique is described, for example, in U.S. Patent No. 6,331,268.

[0051] Of course, other techniques may be used to maintain the fibers aligned in the machine direction. For example, deflector vanes or other mechanical elements may be used, as described in U.S. Patent Nos. 5,366,793 and 7,172,398. The direction of the air flow used to dampen the fibers during their formation may also be adjusted to influence machine direction alignment, as described in U.S. Patent No. 6,524,521. In addition to the method described above, other known techniques for forming the fibers may be used. In one aspect, for example, the fibers may be quenched after formation and then deposited directly onto a forming screen without prior drawing in the manner described above.In these aspects, as described above, the flow velocity of this air stream may be kept relatively low to enhance the tendency of the fibers to remain aligned in the MD direction. However, it should be understood that in one aspect, the fibers are not primarily aligned in the MD direction.

[0052] With further reference to Fig.2, after the fibers 23 have been formed, they may be heated by a diffuser 33, which may blow hot air onto the surface of the fibers to easily bond them together for further processing. As an alternative to the diffuser, a hot air knife may also be used. Other techniques may also be employed to provide web integrity, such as heated calender rolls. In any event, the resulting fibers may thereafter be bonded to form a consolidated, coherent nonwoven web structure, for example, to form the elastomeric cover layer of the present disclosure. In general, any suitable bonding technique may be used in the present disclosure, such as adhesive or autogenous bonding (e.g., fusion and / or self-adhesion of the fibers without an externally applied adhesive).Autogenous bonding can be achieved, for example, by contacting the fibers while they are semi-molten or tacky, or simply by mixing a tackifying resin and / or a solvent with the polymer composition used to form the fibers. Suitable autogenous bonding techniques include ultrasonic bonding, thermal bonding, through-air bonding, and so on. In thermal point bonding, for example, a nip is typically formed between two rolls, at least one of which is patterned. In ultrasonic bonding, on the other hand, a nip is typically formed between a sonotrode and a patterned roll. Although the use of bicomponent fibers has been described in detail above, extensible or elastomeric monocomponent fibers can also be used to produce the fibers for the nonwoven web material (e.g., the cover layer).

[0053] The spunbonded web can also be subjected to one or more additional post-treatment steps. For example, the spunbonded web can be stretched in the cross-machine direction using known techniques such as tenter frame stretching, grooved roller stretching, etc. The spunbonded web can also be subjected to other known processing steps, such as perforation, heat treatments, etc. Strength-forming layer

[0054] As described above, the nonwoven materials prepared according to the present disclosure include at least one softness-enhancing layer as described above in combination with at least one strength-providing layer. The strength-providing layer may be directly attached to the softness-enhancing layer or separated from the softness-enhancing layer by other layers.

[0055] The strength-forming layer may be formed from continuous filaments or fibers and may also comprise a spunbonded web. The fibers may be formed from a non-elastomeric polymer, such as a polyolefin. Suitable polyolefins may include, but are not limited to, homopolymers, copolymers, and terpolymers of ethylene (e.g., low density polyethylene, high density polyethylene, linear low density polyethylene, etc.), propylene (e.g., syndiotactic, atactic, isotactic, etc.), butylene, etc. Additionally, blends and combinations of the foregoing are also suitable for use in connection with the present invention. For example, in one embodiment, the polymer portion of the polymer composition includes greater than about 65 wt. % polyolefin polymer(s), and in certain embodiments, the polymer may comprise at least about 65, 70, 75, 80, 85, 90, 95 wt.-% olefin polymer and / or less than about 100, 99, 98 or 97 wt. % olefin polymer. Further, in a particular embodiment, the polymer portion of the polymer composition may consist entirely of olefin polymers, such as entirely of polymers selected from the group of propylene, ethylene and butylene polymers. The polymer composition has a melt flow rate (MFR) of less than about 60 dg / min and, in certain embodiments, an MFR of greater than about 5, 8, 10, 12 or 15 dg / min and / or less than about 55, 53, 50, 48 or 45 dg / min. Further, as known in the art, the polymer composition may optionally contain one or more fillers, colorants (e.g., TiO 2, pigments), antioxidants, plasticizers, surfactants, lubricants, etc. In particular, as known in the art, one or more lubricants, such as fatty acid amides, may be added to the polymer composition for melt spinning.

[0056] In one aspect, the strength-forming layer is formed from non-elastomeric fibers that are relatively small in size. For example, the fibers may have a denier of less than about 2, such as less than about 1.5. Referring to Fig. 3, for example, an embodiment of a method and system 110 for producing strength-building layers is shown.

[0057] In one embodiment, the polymer composition (not shown), typically in the form of pellets, is provided in a hopper 112 and fed into an extruder 114, which melts the polymer portion of the composition and forms an initial stream of molten polymer. The molten polymer stream is pumped via lines 116 to the spinneret 120. While suitable ranges vary for particular polymers, generally speaking, to limit degradation or other undesirable effects on the polymers, the molten polymer is typically not heated to a temperature greater than about 150°C, 125°C, 100°C, or 85°C of its melting point. In certain embodiments, the polymer may be heated to a temperature between about 30°C and about 150°C, or between about 45°C and about 125°C above its melting point.

[0058] The spinning assembly 120 may include various components. For example, the spinning assembly 120 may include a manifold, a filter or screen, a support plate, and a spinneret positioned downstream of the spinning assembly 120. For example, the molten polymer stream supplied to the manifold may distribute the molten polymer over a wider area by directing the molten polymer stream laterally and downwardly toward the spinneret. The screen or filter serves to filter contaminants or other unwanted foreign matter from the molten streams to prevent spinneret fouling. Suitable screens may, for example, comprise one or more stacked screens ranging from about 50 to about 350 mesh.

[0059] In one aspect, the spinneret includes a conduit pattern extending through the thickness of the spinneret, in which the molten polymer flows through inlet orifices and thence through associated inlet channels or wells. The molten polymer then enters capillaries that exit through an orifice. Each capillary may, for example, have the same diameter as the exit orifice. In one embodiment, the portion of the conduit above the capillary (e.g., upstream) may have a substantially larger diameter than the capillary. For example, the portion of the conduit above the capillary may have a diameter that is at least about 250%, such as at least about 350%, such as at least about 450%, larger than the capillary diameter.

[0060] The size of the exit orifices and the capillary may vary, for example, with a diameter between about 0.2 mm and about 0.45 mm. In certain embodiments, the exit orifice and / or capillary may have a diameter of at least 0.2 mm, 0.23 mm, 0.25 mm, 0.28 mm, or 0.29 mm and / or a diameter of less than about 0.45 mm, 0.42 mm and 0.40 mm, 0.39 mm, or 0.38 mm. As used herein, the diameter for non-circular orifices is determined via the longest diameter line of the orifice. The length of the capillary (L) is proportional to the diameter (D) of the exit orifice, and the length of the capillary divided by the orifice diameter (L / D) is at least about 4. In certain embodiments, the L / D may be equal to or greater than about 4.0, 4.3, 4.5, 4.7, 5.0, 5.3, 5.5, 5.7, 6.0, 6.3, or 6.5, and / or the L / D may be less than about 10.5, 10.0, 9.7, 9.5, 9.3, 9.0, 8.7, 8.5, 8.3, or 8.0.For example, the L / D ratio may be between about 4 and about 10, between about 5 and about 10, between about 6 and about 10, between about 5 and about 9, between about 6 and about 9, or even between about 6 and about 8.

[0061] The pattern of conduits, capillaries, and orifices in the spinneret can vary depending on the application. For example, the spinneret can include a sequence of parallel rows. In certain embodiments, the inner or central region of the extrusion zone can have less closely spaced orifices compared to the regions adjacent to the CD edges near the quench air stream. The orifice pattern in or near the center of the extrusion zone can include a segment extending into the CD that has a reduced density of conduits or that has no orifices at all. For example, the central region can include a section extending across the CD centerline with an MD width between about 10 and about 60 mm that either has no conduits or, alternatively, has a significantly reduced capillary density (e.g.,a capillary density of less than 70%, 60%, 50%, 40% or 30% of the mean).

[0062] The spinneret may have a relatively high density or close spacing of the orifices, such as those having an orifice or hole density of at least about 3 orifices per cm 2 , wherein the density is measured in terms of the number of orifices within the extrusion area. In certain embodiments, the spinneret may have an orifice density of at least about 3.5, 3.7, 4, 4.3, 4.5, 4.7, 5, 5.3, 5.5, 5.7, 6, 6.5, 6.7, 7, 7.3, or 7.5 orifices per cm 2 and / or not more than about 20, 19.5, 19, 18.7, 18.5, 18.3, 18, 17.7, 17.5, 17.3, 17, 16.7, 16.5, 16.3, 16, 15.7, 15.5, 15.3, 15, 14.7, 14.5, 14.3 or 14 cm 2In another aspect, the number of exit orifices within the spinneret is greater than 5000 per meter of extrusion face length (CD length), and in certain embodiments, greater than about 6000 / M, 6500 / M, 7000 / M, 7500 / M, 8000 / M, or even 8500 / M per meter of extrusion face length (CD length).

[0063] The molten polymer is pumped into and through the spinneret assembly and spinneret at high pressures to achieve the throughputs and exit velocities discussed herein. The molten polymer is extruded from the exit orifices at rates of at least about 0.3 g / hole / minute, or "g / hr / m." To calculate g / hr / m, the mass of the extrudate composition pumped through the spinneret over a selected period of time is divided by the number of exit orifices and the selected time. The extrusion rate may, in certain embodiments, be at least about 0.3 g / h / m, 0.33 g / h / m, 0.35 g / h / m, 0.37 g / h / m, 0.4 g / h / m, 0.43 g / h / m, or 0.45 g / h / m and / or at most about 0.6 g / h / m, 0.57 g / h / m, 0.55 g / h / m, 0.53 g / h / m, or 0.5 g / h / m.In another aspect, the molten extrudate is pumped through and out of the spinneret at an exit velocity of greater than about 10 feet / minute, and in certain embodiments may be at least about 10.3, 10.5, 10.7, 11, 11.3, 11.5, 11.7, 12, 12.3, or 12.5 feet / minute and / or no more than about 45, 43, 40, 38, 35, 33, 30, 28, 25, or 23 feet / minute. The exit velocity (V. e ) of the extrudate at the outlet openings is calculated using the following formula: Ve=Mf / EρA M f = Mass flow of extrudate (lb. / min.) E = number of outlet openings p = density of the molten extrudate (lb. / ft 3 ) A = cumulative cross-sectional area of ​​the outlet openings (ft 2 )

[0064] In another aspect, the temperature of the polymer can be controlled region by region, either as it enters the spinning assembly or as it passes through the spinning assembly, such that the temperature of the molten polymer extrudate exiting the exit orifices near the quench air is higher than the temperature of the molten polymer extrudate exiting the exit orifices inside the spinneret and extrusion region. With respect to the embodiments described herein, molten polymer at a first temperature would be extruded from the rows of exit orifices near the CD edge, and molten polymer at a second temperature (below the first temperature) would be extruded from rows of exit orifices near the center of the spinneret and spinneret region.The quenching air first impacts and passes through the outer portions of the bundle, and this, along with the cooling of the molten filaments, warms the quenching air before it impacts the inner or centrally located filaments within the bundle. Having the outer extruded filaments at a slightly higher temperature than the inner extruded filaments improves processing under the conditions described here and creates a more uniform frost line across the entire filament bundle.

[0065] As the molten polymer composition extrudes from the spinneret orifices, a bundle of molten strands forms, extending downward and away from the spinneret. Immediately below the lower surface of the spinneret are fans 140 and 141, which direct cooling or quenching air 142 and 143 into the bundle to at least partially solidify the molten strands 130.

[0066] Various quench air systems are known in the art that can be used in conjunction with the present invention. The quench air can be provided by a single blower at a single temperature or by multiple blowers at different temperatures. For example, a quench system can include a stack of multiple quench air blowers on one or both sides of the bundle, with the upper air boxes providing air at different temperatures than that provided by quench air boxes located below. The quench air temperature varies with the properties of the polymers being melted, the extrusion temperature, the quench air speed, the filament speed, the filament density, and other factors, as known in the art. Generally speaking, quench air is provided at temperatures between about 5-60°C or about 5-35°C.Additionally, the quenching air can be provided at speeds between approximately 30-120 m / min. Typically, the quenching air is introduced into the filament bundle at an angle perpendicular or substantially perpendicular to the direction of filament flow. However, the quenching air can also be introduced into the molten filaments at an angle relative to the direction of filament flow that is slightly acute or obtuse (i.e., slightly upward or downward).

[0067] As from Fig.3, the quenched, solidified, or substantially solidified filaments 132 are then fed to a filament drawing unit 150, which further attenuates or reduces the diameter of the filaments 130, 132. The filament drawing unit 150 has at least two walls 154 defining channels 153, 155 through which high-velocity air pneumatically draws the filaments 132 downwardly away from the spinneret 124 and toward the forming screen 160. The quenched filaments 132 first enter the restricted intake opening 151 and are directed through an upper restricted channel 153. The restricted opening is typically one having an MD width no greater than about 25% of the MD width of the extrusion zone.In certain embodiments, the restricted opening may have an MD width that is no more than about 20%, 18%, 15%, 12%, or 10% of the MD width of the extrusion region, and / or an MD width that is no less than about 0.5%, 1%, 2%, or 3% of the MD width of the extrusion region. The CD width of the restricted opening may be approximately equal to the CD length of the extrusion region, and in certain embodiments, may have a CD length that is at least about 1%, 2%, 4%, or 5% longer than the CD length of the extrusion region. The quenched filaments and the quench air enter the restricted opening together.

[0068] Additional high-velocity air or drawing air may also be introduced into the fiber drawing unit, as directed into the upper narrow channel 153 via conduits and fans in fluid communication therewith. In addition, the drawing air introduced into the channel(s) of the drawing unit may be introduced at velocities greater than about 50 m / s or 75 m / s. The drawing air may be introduced into the channel(s) from one or more sides of the drawing unit and at one or more locations vertically within the drawing unit. The introduction angle may be either perpendicular to the direction of filament flow or inclined downward.

[0069] The fiber drawing unit may have additional channels below the first constriction opening and the associated channel. The additional channels below the first constricted opening and the associated channel may be sequentially smaller, wider than the constricted opening, or have sections of different MD widths. With respect to the Fig. 3, the lower channel 155 is wider than the narrow upper channel 153 associated with the narrowed opening 151. The filaments are discharged through the second lower channel 155 and then through the outlet opening 157 from the

[0070] Draw unit 150. In the embodiment shown, the velocity of the air flowing downward through the draw unit draws the fibers downward away from the spinneret and toward the forming surface. This downward force on the continuous filaments imparts a corresponding pulling or tensile force, which is transmitted along the quenched filaments and extruded molten filaments. In closed systems, the pressure differential is also a primary driver of the drawing air and filaments. A sufficient drawing distance is required to sufficiently draw the fibers downward. The distance between the bottom surface of the spinneret and the convergence of the bundle at a constricted channel opening above the drawing section is at least about 90 cm and, in certain embodiments, can be between about 90 cm and about 300 cm, or even between about 100 and about 230 cm. With respect to the Fig.3, the drawing distance extends from the bottom surface 190 of the spinneret 124 to the inlet opening 151 of the narrow channel 153 at the top of the fiber drawing unit 150.

[0071] The pneumatic forces acting on the filaments are designed to achieve a draw ratio of no more than about 1100, and in certain embodiments may be at least about 250, 280, 300, 330, 350, 380, 400, 430, 450, 480, 500, 530, 550, 580, 600, 630, or 650 and / or no more than about 1100, 1080, 1050, 1030, 1000, 980, or 950. The draw ratio is calculated by multiplying the final speed (V T ) by the exit velocity (V E , explained above) is divided as follows: Stretch ratio=VTVE

[0072] The final speed is calculated as follows: VT=VE×AEAT where: VE = initial velocity, as discussed above AE = the cross-sectional area of ​​the diameter of the outlet opening AT = the cross-sectional area of ​​the resulting filament

[0073] The entraining air forming the pneumatic forces on the filaments enters the system from the openings or gaps between the various components above the draw unit and the various blowers. However, the filament draw unit typically uses additional air blowers or other air supplies, as known in the art. The walls 154 of the draw unit 150 can optionally be moved inward or outward to change the size of the channel at various locations within the draw unit. In certain embodiments, the walls 154 can be moved inward or outward in discrete sections to form a channel of different dimensions or widths to adjust the pulling forces and the distribution of the filaments within the bundle.Further, to improve the uniform distribution and coverage of the formed nonwoven web, a baffle 156 may be used to distribute the filaments, as is known in the art. Optionally, electrostatic charge bars (not shown) or other components may also be employed to assist in filament distribution, web formation, and laydown. While the drawings illustrate an open air melt spinning system, it is to be understood that the process of the present invention will also function with closed air systems, as is known in the art. Examples of various quench and draw systems suitable for use in the present invention include those described in U.S. Pat. No. 4,340,563 to Appel et al., U.S. Pat. No. 5,935,512 to Haynes et al., U.S. Pat. No. 6,692,601 to Najour et al., U.S. Pat. No. 6,783,722 to Taylor, US Pat. No. 7,037,097 Wilkie et al., US Pat. No.7,762,800 to Geus et al., U.S. Pat. No. 8,246,898 to Conrad et al., U.S. Pat. No. 8,333,918 to Lennon et al. and US2017 / 0211217 Nitschke et al. are described.

[0074] The fully drawn filaments 134 exit the bottom of the filament drawing unit 150 through the exit opening 157 and are deposited onto a forming surface 160, such as a web or screen. As is known in the art, one or more vacuums 162 are disposed below the forming surface 160 to draw the filaments onto the forming surface 160 and form a relatively loose mat or web 136 of filaments 134. The vacuums also remove the drawing air to prevent deflected air from disturbing the filament deposition and / or disturbing the mat 136 after it has been deposited onto the screen. Drawing air from below the drawing unit can also help drive the movement of air and fibers through the drawing unit and onto the forming screen.

[0075] Optionally, the mat of filaments may be treated to impart a minimal degree of integrity necessary for additional handling. Such treatment may include, for example, consolidating the mat with a compaction roll (not shown) or by using a high-speed through-air joiner 164. Such through-air joiners impart only minimal filament-to-filament bonding necessary for additional handling and processing and without significant melting of the filaments. Such joiners and methods are described in U.S. Pat. No. 5,707,468 to Arnold et al. Additionally, to achieve relatively higher basis weights, multiple rows of spinnerets and drawing units may be sequentially arranged above the perforated forming surface upstream of the consolidation and / or bonding device.

[0076] After formation, the nonwoven mat is desirably bonded to increase its overall integrity and strength. In one aspect, the mat may be mechanically bonded, for example, by entangling. The filaments may be entangled by hydroentangling, wherein the mat is subjected to one or more series of fine, high-pressure water jets such that the filaments become sufficiently entangled to form a continuous nonwoven web. In other embodiments, the mat may be bonded by one or more techniques known in the art, such as adhesive, pressure, heat, and / or ultrasonic energy.In certain aspects, the mat may be bonded, as is known in the art, using a pair of bonding rollers 166, 168, with at least one of the rollers having a pattern of protrusions or "pins" corresponding to the desired pattern of bonding points to be imparted to the mat, forming a bonded nonwoven web 138. The two cooperating rollers form a nip through which the mat is passed under pressure and optionally heat. While suitable bonding elements may be formed without the application of heat, the use of heat in conjunction with pressure is preferred. The bonding may be achieved, as is known in the art, using a nip formed by a patterned roller and a smooth anvil roller ("pin-to-flat") or by two matched patterned rollers ("pin-to-pin").With respect to the use of a smooth anvil roll, the roll may be a steel roll or, alternatively, coated with a resilient material. By way of example only, various pattern bonding methods are illustrated and described in U.S. Pat. No. 3,855,046 to Hansen et al., U.S. Pat. No. 4,333,979 to Sciaraffa et al., U.S. Pat. No. 4,374,888 to Bornslaeger, U.S. Pat. No. 5,110,403 to Ehlert, U.S. Pat. No. 5,858,515 to Stokes et al., U.S. Pat. No. 6,165,298 to Samida et al., etc. As known in the art, pressures, temperatures, residence time, base film composition, basis weight, and other parameters influence the choice of the desired degree of pressure and / or heat applied to the base film to form the bond points. Alternatively, the mat of filaments can be bonded by spraying, gravure rolling, or other means of applying adhesive in the desired pattern, as known in the art.

[0077] The resulting nonwoven fabric desirably exhibits high tensile strength, uniform opacity (coverage), and / or pleasant hand. For many applications, the bonded nonwoven fabric can have a basis weight of less than about 175 g / m 2 In certain embodiments, the nonwoven fabrics may have a basis weight of less than about 150 g / m 2 , 120 g / m 2 , 90 g / m 2 , 60 g / m 2 , 45 g / m 2 , 35 g / m 2 , 30 g / m 2 , 25 g / m 2 , 20 g / m 2 , 18 g / m 2 , 16 g / m 2 , 14 g / m 2 , 12 g / m 2 , 10 g / m 2 , 9 g / m 2 , 8 g / m 2 , 7 g / m 2 and may further, in certain embodiments, have a basis weight above about 4 g / m 2 , 5 g / m 2 , 7 g / m 2 or 10 g / m 2Furthermore, the filaments as formed by this process and provided in the corresponding nonwoven fabric may have an average denier (g / 9000M) of less than about 1.5 or less, and in certain embodiments, an average fiber denier equal to or less than about 1.4, 1.3, or 1.2 and / or at least about 0.7, 0.73, 0.75, 0.77, 0.8, 0.83, 0.85, 0.87, or 0.9. Similarly, the filaments as formed by this method and provided in the corresponding nonwoven fabric may have an average fiber size of less than or equal to about 16 microns, and in certain embodiments, an average fiber size of equal to or less than about 16, 15.8, 15.5, 15.3, 15, 14.8, or 14.5 microns and / or at least about 10, 10.3, 10.5, 10.8, 11, 11.3, 11.5, 11.8, or 12. Multilayer nonwoven material

[0078] According to the present disclosure, at least one strength-providing layer is combined with at least one softness-enhancing layer to produce a multipurpose nonwoven material. Generally, the softness-enhancing layer forms an outer top surface of the nonwoven material. The strength-providing layer, however, may form the bottom layer or a middle layer of the material. The strength-providing layer and the softness-enhancing layer may be as in Fig. 2 and Fig. 3 and subsequently combined to form a multilayer nonwoven web. The two layers can be attached to each other by any suitable bonding method, including thermal bonding, adhesive bonding, ultrasonic bonding, or the like.

[0079] Alternatively, as in Fig. 4, a two-bank melt spinning system and a process as in Fig.4, can be used to produce the nonwoven material. As shown in Fig. 4, the method for producing the nonwoven material includes, for example, a system 110 for producing strength-providing layers and a system 21 for producing softness-enhancing layers. The systems include spunbond extruders 110 and 21 that produce fibers 50, which are then deposited on a forming screen 52. If desired, a vacuum may be used to hold the fibers on the forming screen 52. The spunbond fibers 50 produce a softness-enhancing layer on a strength-providing layer to produce a web 54. The web 54 may optionally be densified by a densification roll 56. As shown, a multi-layer nonwoven material 30 is produced, which is then wound into a roll 62.

[0080] In the Fig.4, a two-layer nonwoven material 30 is produced. However, it should be understood that additional extruders may be arranged in series to produce nonwoven materials having more than two layers. The additional layers may be additional strength-providing layers, additional softness-enhancing layers, or other layers, as desired. For example, the nonwoven material may include from about 2 to about 10 strength-providing layers (including any increments of a strength-providing layer therebetween), and the nonwoven material may include from about 2 to about 10 softness-enhancing layers (including any increments of a softness-enhancing layer therebetween). In one aspect, the nonwoven material includes from about 3 to about 8 layers, including 1, 2, 3, 4, 5, or 6 strength-providing layers, and the remainder softness-enhancing layers.In another aspect, the nonwoven material contains 4 layers, which include 1, 2 or 3 strength-building layers and the rest softness-enhancing layers.

[0081] The nonwoven materials made according to the present disclosure can be used in numerous and varied applications. For example, the nonwoven material can be used in an absorbent article. An absorbent article refers to any article capable of absorbing water or other liquids. Examples of some absorbent articles include, but are not limited to, absorbent personal care articles, such as diapers, training pants, absorbent briefs, incontinence articles, feminine care products, swimwear, baby wipes, and the like; medical absorbent articles, such as garments, fenestration materials, underpads, bed pads, bandages, absorbent drapes, and medical wipes; food service wipes; clothing articles, and so on.

[0082] The nonwoven material 30 produced according to the present disclosure may generally have a basis weight of about 5 g / m 2 up to about 300 g / m 2 including all increments of 1 g / m 2 In one embodiment, the basis weight of about 5 g / m 2 up to about 170 g / m 2 Particularly advantageously, according to the present disclosure, very lightweight materials can be produced which exhibit considerable strength with excellent softness properties. The above properties can be achieved, for example, at basis weights of less than about 30 g / m 2 , such as less than about 25 g / m 2 , such as less than about 20 g / m 2 , such as less than about 18 g / m 2 , and with basis weights generally exceeding about 7 g / m 2 , such as more than about 9 g / m 2, such as more than about 11 g / m 2 , such as more than about 13 g / m 2 can be achieved.

[0083] The weight ratio between the strength-providing layer(s) and the softness-enhancing layer(s) can also vary depending on the application. In one embodiment, the softness-enhancing layer can have a greater basis weight than the strength-providing layer. Alternatively, the strength-providing layer can have a higher basis weight than the softness-enhancing layer. In one embodiment, the weight ratio between the strength-providing layer and the softness-enhancing layer is about 1:5 to about 5:1, such as about 1:4 to about 4:1, such as about 1:3 to about 3:1, such as about 1:2 to about 2:1, such as about 1:3 to about 1.5:1, such as about 1:2 to about 1.1:1. Elastic laminate

[0084] In one embodiment, the nonwoven material of the present disclosure may be incorporated into an elastic laminate. For example, the nonwoven material may be mounted on an elastic backing. The elastic backing may be a film or may comprise a plurality of parallel filaments, such as ribbons.

[0085] In some implementations, the elastic film (e.g., sheet) is formed from one or more elastomeric polymers that are melt-processable, i.e., thermoplastic. Generally, any of a variety of thermoplastic elastomeric polymers can be used, including, for example, elastomeric polyesters, elastomeric polyurethanes, elastomeric polyamides, elastomeric copolymers, elastomeric polyolefins, etc. In some implementations that involve perforation of the film, elastomeric semi-crystalline polyolefins are used due to their unique combination of mechanical and elastomeric properties. That is, the mechanical properties of such semi-crystalline polyolefins enable the formation of films that perforate easily upon thermal bonding, yet retain their elasticity.

[0086] Semi-crystalline polyolefins have, or may have, a substantially regular structure. For example, semi-crystalline polyolefins may be substantially amorphous in their undeformed state, but upon stretching, form crystalline domains. The degree of crystallinity of the olefin polymer may range from about 3% to about 30%, in some embodiments from about 5% to about 25%, and in some embodiments from about 5% to about 15%. Likewise, the semi-crystalline polyolefin may have a latent heat of fusion (ΔHf), which is another indicator of the degree of crystallinity, from about 15 to about 75 joules per gram ("J / g"), in some embodiments from about 20 to about 65 J / g, and in some embodiments from 25 to about 50 J / g.The semi-crystalline polyolefin may also have a Vicat softening temperature of about 10°C to about 100°C, in some embodiments from about 20°C to about 80°C, and in some embodiments from about 30°C to about 60°C. The semi-crystalline polyolefin may have a melting temperature of about 20°C to about 120°C, in some embodiments from about 35°C to about 90°C, and in some embodiments from about 40°C to about 80°C. The latent heat of fusion (ΔHf) and melting temperature may be determined using differential scanning calorimetry ("DSC") according to ASTM D-3417, as is well known to those skilled in the art. The Vicat softening temperature may be determined in accordance with ASTM D-1525.

[0087] Exemplary semi-crystalline polyolefins include polyethylene, polypropylene, blends, and their copolymers. In one particular embodiment, a polyethylene is used that is a copolymer of ethylene and an α-olefin, such as a C3-C20 α-olefin or C3-C12 α-olefin. Suitable α-olefins can be linear or branched (e.g., one or more C1-C3 alkyl branches or an aryl group). Specific examples include 1-butene; 3-methyl-1-butene; 3,3-dimethyl-1-butene; 1-pentene; 1-pentene with one or more methyl, ethyl, or propyl substituents; 1-hexene with one or more methyl, ethyl, or propyl substituents; 1-heptene with one or more methyl, ethyl, or propyl substituents; 1-Octene with one or more methyl, ethyl, or propyl substituents; 1-nonene with one or more methyl, ethyl, or propyl substituents; ethyl-, methyl-, or dimethyl-substituted 1-decene; 1-dodecene, and styrene.Particularly desirable α-olefin comonomers are 1-butene, 1-hexene, and 1-octene. The ethylene content of such copolymers can range from about 60 mol% to about 99 mol%, in some embodiments from about 80 mol% to about 98.5 mol%, and in some embodiments from about 87 mol% to about 97.5 mol%. The α-olefin content can similarly range from about 1 mol% to about 40 mol%, in some embodiments from about 1.5 mol% to about 15 mol%, and in some embodiments from about 2.5 mol% to about 13 mol%.

[0088] The density of polyethylene can vary depending on the type of polymer used, but generally ranges from 0.85 to 0.96 grams per cubic centimeter ("g / cm3"). Polyethylene "plastomers," for example, have a density ranging from about 0.85 to about 0.91 g / cm3. Similarly, "linear low-density polyethylene" ("LLDPE") can have a density ranging from 0.91 to 0.940 g / cm3; "low-density polyethylene" ("LDPE") can have a density ranging from 0.910 g / cm3 to 0.940 g / cm3; and "high-density polyethylene" ("HDPE") can have a density ranging from 0.940 g / cm3 to 0.960 g / cm3. Densities can be measured according to ASTM 1505.

[0089] Exemplary polyethylene copolymers include those that are "linear" or "substantially linear." The term "substantially linear" means that the ethylene polymer contains long-chain branches in the polymer backbone in addition to the short-chain branches resulting from the incorporation of comonomers. "Long-chain branch" refers to a chain length of at least 6 carbons. Each long-chain branch can have the same comonomer distribution as the polymer backbone and be as long as the polymer backbone to which it is attached. Preferred substantially linear polymers are substituted with from 0.01 long-chain branches per 1000 carbons to 1 long-chain branch per 1000 carbons, and in some implementations, from 0.05 long-chain branches per 1000 carbons to 1 long-chain branch per 1000 carbons.In contrast to the term "essentially linear," the term "linear" means that the polymer has no measurable or detectable long-chain branches. That is, the polymer is substituted with an average of less than 0.01 long-chain branches per 1000 carbon atoms.

[0090] Exemplary plastomers for use in forming the film include ethylene-based copolymer plastomers available under the designation EXACT™ from ExxonMobil Chemical Company of Houston, Texas. Other suitable polyethylene plastomers are available under the designations ENGAGE™ and AFFINITY™ from The Dow Chemical Company of Midland, Michigan. Other suitable ethylene polymers are available from The Dow Chemical Company under the designations DOWLEX™ (LLDPE) and ATTANE™ (ULDPE). Other suitable ethylene polymers are described in U.S. Patent Nos. 4,937,299 to Ewen et al., 5,218,071 to Tsutsui et al., 5,272,236 to Lai et al., and 5,278,272 to Lai et al., all of which are incorporated herein by reference for all purposes.

[0091] Other polymers, for example, propylene polymers, may also be suitable for use as semi-crystalline polyolefins. Suitable plastomeric propylene polymers may include, for example, copolymers or terpolymers of propylene, copolymers of propylene with an α-olefin (e.g., C3-C20), such as ethylene, 1-butene, 2-butene, the various pentene isomers, 1-hexene, 1-octene, 1-nonene, 1-decene, 1-unidecene, 1-dodecene, 4-methyl-1-pentene, 4-methyl-1-hexene, 5-methyl-1-hexene, vinylcyclohexene, styrene, etc. The comonomer content of the propylene polymer may be about 35 wt.% or less, in some implementations from about 1 wt.% to about 20 wt.%, and in some embodiments from about 2 wt.% to about 10 wt.%. Preferably, the density of the polypropylene (e.g., propylene / α-olefin copolymer) may be 0.91 grams per cubic centimeter (g / cm 3 ) or less, in some embodiments 0.85 to 0.88 g / cm 3 and in some embodiments 0.85 g / cm3 up to 0.87 g / cm 3 Suitable propylene polymers are also available under the designations VISTAMAXX™ from ExxonMobil Chemical Co. in Houston, Texas; FINA™ (e.g., 8573) from Atofina Chemicals in Feluy, Belgium; TAFMER™ from Mitsui Petrochemical Industries; and VERSIFY™ from Dow Chemical Co. in Midland, Michigan. Further examples of suitable propylene polymers are described in U.S. Pat. No. 6,500,563 to Datta et al.; U.S. Pat. No. 5,539,056 to Yang, et al.; and U.S. Pat. No. 5,596,052 to Resconi, et al., which are incorporated herein by reference in their entirety for all purposes.

[0092] A variety of known processes can generally be used to form semi-crystalline polyolefins. For example, olefin polymers can be formed using a free radical or a coordination catalyst (e.g., Ziegler-Natta). Preferably, the olefin polymer is formed from a complex-coordinative single-site catalyst, such as a metallocene catalyst. Such a catalyst system produces ethylene copolymers in which the comonomer is randomly distributed within a molecular chain and uniformly distributed across the different molecular weight fractions. Metallocene-catalyzed polyolefins are described, for example, in U.S. Pat. Nos. 5,571,619 to McAlpin et al.; 5,322,728 to Davis et al.; 5,472,775 to Obijeski et al.; 5,272,236 to Lai et al.; and 6,090,325 to Wheat, et al., which are incorporated herein by reference in their entirety for all purposes.Examples of metallocene catalysts include bis(n-butylcyclopentadienyl)titanium dichloride, bis(n-butylcyclopentadienyl)zirconium dichloride, bis(cyclopentadienyl)scandium chloride, bis(indenyl)zirconium dichloride, bis(methylcyclopentadienyl)titanium dichloride, bis(methylcyclopentadienyl)zirconium dichloride, cobaltocene, cyclopentadienyltitanium trichloride, ferrocene, hafnocene dichloride, isopropyl(cyclopentadienyl-1-flourenyl)zirconium dichloride, molybdocene dichloride, nickelocene, niobocene dichloride, ruthenocene, titanocene dichloride, zirconocene chloride hydride, zirconocene dichloride, and so on. Polymers prepared using metallocene catalysts typically have a narrow molecular weight range. For example, metallocene-catalyzed polymers can exhibit polydispersity numbers (Mw / Mn) below 4, a controlled short-chain branching distribution, and a controlled isotacticity.

[0093] The melt flow index (MI) of semi-crystalline polyolefins can generally vary, but typically ranges from about 0.1 grams per 10 minutes to about 100 grams per 10 minutes, in some embodiments from about 0.5 grams per 10 minutes to about 30 grams per 10 minutes, and in some embodiments from about 1 to about 10 grams per 10 minutes, determined at 190°C. The melt flow index is the weight of polymer (in grams) that can be forced through an extrusion rheometer orifice (0.0825 inch diameter) when subjected to a force of 5000 grams in 10 minutes at 190°C and can be determined according to ASTM Test Method D1238-E.

[0094] Of course, other thermoplastic polymers can also be used to form the elastic film, either alone or in combination with the semi-crystalline polyolefins. For example, a substantially amorphous block copolymer comprising at least two blocks of a monoalkenyl arene polymer separated by at least one block of a saturated conjugated diene polymer can be used. The monoalkenyl arene blocks can include styrene and its analogues and homologs, such as o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, p-methylstyrene, etc., as well as other monoalkenylic polycyclic aromatic compounds, such as vinylnaphthalene, vinylanthrycene, and so on. Preferred monoalkenyl arenes are styrene and p-methylstyrene.The conjugated diene blocks can include homopolymers of conjugated diene monomers, copolymers of two or more conjugated dienes, and copolymers of one or more of the dienes with another monomer, in which the blocks consist predominantly of conjugated diene units. Preferably, the conjugated dienes contain 4 to 8 carbon atoms, such as 1,3-butadiene (butadiene); 2-methyl-1,3-butadiene; isoprene; 2,3-dimethyl-1,3-butadiene; 1,3-pentadiene (piperylene); 1,3-hexadiene; and so on.

[0095] Exemplary thermoplastic elastomeric copolymers are available from Kraton Polymers LLC of Houston, Tex., under the trade name KRATON®. KRATON® polymers include styrene-diene block copolymers, such as styrene-butadiene, styrene-isoprene, styrene-butadiene-styrene, and styrene-isoprene-styrene. KRATON® polymers also include styrene-olefin block copolymers formed by selective hydrogenation of styrene-diene block copolymers. Examples of such styrene-olefin block copolymers include styrene-(ethylene-butylene), styrene-(ethylene-propylene), styrene-(ethylene-butylene)-styrene, styrene-(ethylene-propylene)-styrene, styrene-(ethylene-butylene)-styrene, styrene-(ethylene-butylene)-styrene-(ethylene-butylene), styrene-(ethylene-propylene)-styrene-(ethylene-propylene), and styrene-ethylene-(ethylene-propylene)-styrene. These block copolymers can have a linear, radial, or star molecular configuration. Special KRATON® block copolymers include the products marketed under the brand names G 1652, G 1657, G 1730, MD6673, and MD6973.Various suitable styrenic block copolymers are described in U.S. Pat. Nos. 4,663,220, 4,323,534, 4,834,738, 5,093,422, and 5,304,599, which are hereby incorporated by reference in their entirety for all purposes. Other commercially available block copolymers include the elastomeric S-EP-S copolymers available from Kuraray Company, Ltd. of Okayama, Japan, under the trade designation SEPTON®. Other suitable copolymers include the elastomeric copolymers SIS and SBS available from Dexco Polymers of Houston, Texas, under the trade designation VECTOR®. Also suitable are polymers consisting of an ABAB tetrablock copolymer, as described in U.S. Pat. No. 5,332,613 to Taylor, et al. which is incorporated herein by reference in its entirety for all purposes.An example of such a tetrablock copolymer is a styrene-poly(ethylene-propylene)-styrene-poly(ethylene-propylene) block copolymer (“S-EP-S-EP”) block copolymer.

[0096] The amount of elastomeric polymer(s) used in the film can vary, but is typically about 30% or more by weight of the film, in some embodiments about 50% or more by weight, and in some embodiments about 80% or more by weight of the film. For example, in one embodiment, the semi-crystalline polyolefin(s) constitute about 70% or more by weight of the film, in some embodiments about 80% or more by weight of the film, and in some embodiments about 90% or more by weight of the film. In other embodiments, blends of semi-crystalline polyolefin(s) and elastomeric block copolymer(s) can be used. In these embodiments, the block copolymer(s) can constitute about 5 to about 50% by weight, in some embodiments about 10 to about 40% by weight, and in some embodiments about 15 to about 35% by weight of the blend. Likewise, the semi-crystalline polyolefin(s) may comprise from about 50% to about 95% by weight.-%, in some embodiments about 60 wt.% to about 90 wt.%, and in some embodiments about 65 wt.% to about 85 wt.% of the blend. However, it should be understood that other elastomeric and / or non-elastomeric polymers may also be used in the film.

[0097] In addition to polymers, the elastic film may also contain other ingredients as known in the art. In one embodiment, for example, the elastic film contains a filler. Fillers are particles or other forms of materials that can be added to the film-polymer extrusion mixture and that do not chemically affect the extruded film, yet may be uniformly dispersed throughout the film. Fillers can serve a variety of purposes, including improving the opacity and / or breathability of the film (i.e., vapor permeable and substantially liquid impermeable). Filled films can be made breathable, for example, by stretching, which separates the polymer from the filler and creates microporous passageways. Breathable microporous elastic films are described, for example, in U.S. Pat. Nos. 5,997,981; 6,015,764 and 6,111,163 to McCormack, et al.; 5,932,497 to Morman, et al.; 6,461,457 to Taylor, et al., which are incorporated herein by reference in their entirety for all purposes.

[0098] The fillers may have a spherical or non-spherical shape with average particle sizes ranging from about 0.1 to about 7 microns. Examples of suitable fillers include, but are not limited to, calcium carbonate, various types of clay, silica, alumina, barium carbonate, sodium carbonate, magnesium carbonate, talc, barium sulfate, magnesium sulfate, aluminum sulfate, titanium dioxide, zeolites, cellulosic powders, kaolin, mica, carbon, calcium oxide, magnesium oxide, aluminum hydroxide, wood pulp powder, wood powder, cellulose derivatives, chitin, and chitin derivatives. If desired, a suitable coating, such as stearic acid, may also be applied to the filler particles. The filler content may vary as used, for example, from about 25% to about 75% by weight, in some embodiments from about 30% to about 70% by weight, and in some embodiments from about 40% to about 60% by weight of the film.

[0099] Other additives may also be added to the film, such as melt stabilizers, processing stabilizers, heat stabilizers, light stabilizers, antioxidants, heat-aging stabilizers, whiteners, antiblocking agents, binders, tackifiers, viscosity modifiers, etc. Examples of suitable tackifying resins include hydrogenated hydrocarbon resins. REGALREZ™ hydrocarbon resins are examples of such hydrogenated hydrocarbon resins and are available from Eastman Chemical. Other tackifiers are available from ExxonMobil under the name ESCOREZ™. Viscosity modifiers such as polyethylene wax (e.g., EPOLENE™ C-10 from Eastman Chemical) may also be used. Phosphite stabilizers (e.g., IRGAFOS, available from Ciba Specialty Chemicals in Terrytown, NY, and DOVERPHOS, available from Dover Chemical Corp. in Dover, Ohio) are exemplary melt stabilizers.Additionally, hindered amine stabilizers (e.g., CHIMASSORB from Ciba Specialty Chemicals) are exemplary heat and light stabilizers. Furthermore, hindered phenols are typically used as antioxidants in film manufacturing. Some suitable hindered phenols include those available from Ciba Specialty Chemicals under the trade name "Irganox®," such as Irganox® 1076, 1010, or E 201. Binders can also be added to the film to facilitate bonding of the film to other materials (e.g., nonwoven webs). When used, such additives (e.g., tackifiers, antioxidants, stabilizers, etc.) may each be present in an amount of from about 0.001% to about 25%, in some embodiments from about 0.005% to about 20%, and in some embodiments from 0.01% to about 15% by weight of the film.

[0100] The elastic film can be single-layer or multi-layer. Multi-layer films can be produced by co-extrusion of the layers, extrusion coating, or by any conventional layering process. Such multi-layer films typically contain at least one base layer and at least one outer layer, but can contain any number of layers. For example, the multi-layer film can be formed from a base layer and one or more outer layers, with the base layer formed from a semi-crystalline polyolefin. In these embodiments, the outer layer(s) can be formed from any film-forming polymer. If desired, the outer layer(s) can contain a softer, lower melting point polymer or a polymer blend that makes the layer(s) more suitable as heat-seal tie layers for thermally bonding the film to a nonwoven web. The outer layer(s) canFor example, they can be formed from an olefin polymer or blends thereof, as described above. Other film-forming polymers that can be used alone or in combination with other polymers include ethylene vinyl acetate, ethylene ethyl acrylate, ethylene acrylic acid, ethylene methyl acrylate, ethylene butyl acrylate, nylon, ethylene vinyl alcohol, polystyrene, polyurethane, and so on.

[0101] The thickness of the outer layer(s) is generally chosen so as not to significantly impair the elastomeric properties of the film. To this end, each outer layer may separately represent from about 0.5% to about 15% of the total thickness of the film, and in some embodiments, from about 1% to about 10% of the total thickness of the film. For example, each outer layer may have a thickness of from about 0.1 to about 10 micrometers, in some embodiments from about 0.5 to about 5 micrometers, and in some embodiments from about 1 to about 2.5 micrometers. Likewise, the base layer may have a thickness of from about 1 to about 40 micrometers, in some embodiments from about 2 to about 25 micrometers, and in some embodiments from about 5 to about 20 micrometers.

[0102] The properties of the resulting film can generally vary as desired. For example, before stretching, the film typically has a basis weight of about 100 grams per square meter or less, and in some embodiments, from about 50 to about 75 grams per square meter. After stretching, the film typically has a basis weight of about 60 grams per square meter or less, in some embodiments, from about 15 to about 35 grams per square meter. The stretched film can also have a total thickness of about 1 to about 100 micrometers, in some embodiments, from about 10 to about 80 micrometers, and in some embodiments, from about 20 to about 60 micrometers.

[0103] Although the carrier is described above as a film, it is understood that the carrier may also be formed as parallel elastic filaments containing ribbons. lamination

[0104] In some implementations, the nonwoven material is laminated to the film by, for example, thermal bonding, adhesive bonding, ultrasonic bonding, pressure bonding, needle perforation, or a combination thereof.

[0105] To simultaneously form apertures and bonds between the film and the nonwoven web material, in some embodiments, lamination is generally achieved by a patterned bonding technique (e.g., thermal point bonding, ultrasonic bonding, etc.) in which the materials are fed to a nip defined by at least one patterned roll. An example of this simultaneous perforating and bonding is described in U.S. Pat. No. 7,803,244 to Siqueira et al., which is incorporated herein by reference in its entirety for all purposes. In thermal point bonding, for example, a nip is typically formed between two rolls, at least one of which is patterned. In ultrasonic bonding, on the other hand, a nip is typically formed between a sonotrode and a patterned roll.

[0106] In particular, the patterned roller includes, for example, a plurality of raised bonding elements to simultaneously bond the film to the nonwoven web material(s) and form apertures in the film. The size of the bonding elements may be specifically tailored to facilitate the formation of apertures in the film and to enhance the bond between the film and the nonwoven material(s). For example, the bonding elements are typically selected to have a relatively large length dimension. The length dimension of the bonding elements may be between about 300 and about 5000 micrometers, in some embodiments between about 500 and about 4000 micrometers, and in some embodiments between about 1000 and about 2000 micrometers.The width dimension of the bonding elements may also range from about 20 to about 500 micrometers, in some embodiments from about 40 to about 200 micrometers, and in some embodiments from about 50 to about 150 micrometers. Furthermore, the "element aspect ratio" (the ratio of an element's length to its width) may range from about 2 to about 100, in some embodiments from about 4 to about 50, and in some embodiments from about 5 to about 20.

[0107] In addition to the size of the bonding elements, the overall bonding pattern can also be selectively controlled to achieve the desired opening formation. For example, in one embodiment, a bonding pattern is selected in which the longitudinal axis (longest dimension along a centerline of the element) of one or more of the bonding elements is skewed relative to the machine direction ("MD") of the elastic film. For example, one or more of the bonding elements can be oriented at an angle of about 30° to about 150°, in some embodiments at an angle of about 45° to about 135°, and in some embodiments at an angle of about 60° to about 120°, with respect to the machine direction of the film. In this way, the bonding elements present the film with a relatively large surface area in a direction substantially perpendicular to the direction of travel of the film.This increases the area over which the shear stress acts on the film, which in turn facilitates the formation of openings.

[0108] The pattern of bonding elements is typically chosen such that the nonwoven composite has a total bond area of ​​less than approximately 50% (as determined by conventional optical microscopy techniques). In some implementations, the film is stretched and subsequently laminated to the nonwoven web with a total bond area between 5% and 30%.

[0109] In some embodiments, the bond density is also typically greater than about 50 bonds per square inch, and in some embodiments, from about 75 to about 500 needle bonds per square inch. One suitable bond pattern for use with this novel elastomeric laminate is known as an "S-weave" and is described in U.S. Pat. No. 5,964,742 to McCormack, et al., which is incorporated herein by reference in its entirety for all purposes. S-weave patterns typically have a bond element density of about 50 to about 500 bond elements per square inch, and in some embodiments, from about 75 to about 150 bond elements per square inch. Another suitable bond pattern is known as a "rib knit" and is described in U.S. Pat. No. 5,620,779 to Levy, et al., which is incorporated herein by reference in its entirety for all purposes.Rib knit patterns typically have a weave density of about 150 to about 400 weaves per square inch, and in some embodiments, about 200 to about 300 weaves per square inch. Another suitable pattern is the "wire mesh" pattern, which has a weave density of about 200 to about 500 weaves per square inch, and in some embodiments, about 250 to about 350 weaves per square inch. Other usable weave patterns are described in U.S. Pat. Nos. 3,855,046 to Hansen et al.; 5,962,112 to Haynes et al.; 6,093,665 to Sayovitz et al.; D375,844 to Edwards, et al.; D428,267 to Romano et al.; and D390,708 to Brown, which are incorporated herein by reference in their entirety for all purposes.

[0110] To achieve such simultaneous opening and bonding without substantial softening of the polymer(s) of the nonwoven web material, the bonding temperature and pressure can be selectively controlled. For example, one or more rollers can be heated to a surface temperature of about 50°C to about 160°C, in some embodiments from about 60°C to about 140°C, and in some embodiments from about 70°C to about 120°C. Likewise, the pressure exerted by the rollers during thermal bonding ("nip pressure") can range between about 75 and about 600 pounds per linear inch, in some embodiments from about 100 to about 400 pounds per linear inch, and in some embodiments from about 120 to about 200 pounds per linear inch. It is understood that the residence time of the materials can influence the bonding parameters used.

[0111] As previously mentioned, another factor that affects the simultaneous formation of openings and bonds is the degree of tension in the film during lamination. For example, increasing the tension in the film is usually accompanied by an increase in the size of the opening. It is understood that excessive film tension can compromise the integrity of the film. Thus, in some implementations, a stretch ratio of approximately 1.5 or more, or 2 to 6, or 2.5 to 7.0, or 3.0 to 5.5 is used to achieve the desired degree of tension in the film during lamination. The stretch ratio can be determined by dividing the final length of the film by its original length. The stretch ratio can also be approximately equal to the draw ratio, which is determined by dividing the linear speed of the film during lamination (e.g., speed of the nip rolls) by the linear speed at which the film is formed (e.g., speed of the nip rolls).B. speed of the casting rolls or blown pressure rolls).

[0112] The film can be "pre-stretched" (prior to lamination) using rollers rotating at different rotational speeds so that the film is stretched in the machine direction to the desired stretch ratio. For example, the film can be stretched in the machine direction by a ratio of 2 to 6, i.e., by 2 to 6 times the unstretched length of the film. This uniaxially stretched film can also be oriented in the cross-machine direction to form a "biaxially stretched" film. The orientation temperature profile during the "pre-stretch" process is generally below the melting point of one or more polymers in the film, but high enough to stretch or elongate the composition. For example, the film can be stretched at a temperature of about 15°C to about 50°C, in some embodiments from about 25°C to about 40°C, and in some embodiments from about 30°C to about 40°C.If the film is “pre-stretched” in the manner described above, the degree of stretch can be increased, maintained, or slightly reduced (retracted) during lamination to achieve the desired degree of tension.

[0113] In other implementations, the lamination process does not involve perforating the film, but rather focuses on bonding the film to the nonwoven web material (e.g., a stretchable or elastomeric cover layer). Lamination without intentionally creating openings can be achieved, for example, through thermal bonding, adhesive bonding, ultrasonic bonding, and / or pressure bonding.

[0114] Fig.Figure 5 shows an exemplary process for forming a composite of an elastic film and a nonwoven web material. The raw materials of the film carrier (e.g., elastomeric polymer) can be dry blended (i.e., without a solvent) and added to a hopper (not shown) of an extrusion apparatus 40. Alternatively, the raw materials can be blended with a solvent. The materials are melt dispersed and blended in the hopper, for example, using batch and / or continuous blending techniques using, for example, a Banbury mixer, a Farrel continuous mixer, a single-screw extruder, a twin-screw extruder, etc.

[0115] The composite material (not shown) fed to the extrusion apparatus 40 is then blown into nip rolls 42 to form a single-layer elastic precursor sheet 10. The rolls 42 may be maintained at a temperature sufficient to solidify and quench the elastic precursor sheet 10 during its formation, such as 20 to 60°C. Typically, the resulting elastic precursor sheet is generally unopened, although it may, of course, contain small cuts or tears as a result of processing.

[0116] The film 10 is stretched and thinned in the machine direction by a film orientation unit or Machine Direction Orienter (MDO) 44, such as is commercially available from Marshall and Williams, Co. in Providence, RI. In some implementations, the MDO includes a plurality of stretch rollers 46 that progressively stretch and thin the film 10 in the machine direction. Although in Fig.5, four pairs of rollers 46 are shown, it should be understood that the number of rollers can be higher or lower depending on the desired degree of stretch and the degree of stretch between the individual rollers. The film 10 can also be stretched in other directions. For example, the film 10 can be clamped at its side edges with chain clamps and conveyed into a stenter oven. In the stenter oven, the film 10 can be stretched to the desired stretch ratio in the transverse direction of the machine using chain clamps that are pulled apart in their forward movement.

[0117] According to the present disclosure, at least one side of the elastic carrier 10 is laminated to a nonwoven material according to the present disclosure. In the Fig.For example, in the embodiment illustrated in Figure 5, the film 10 is laminated on one side to a first nonwoven material and on an opposite side to a second nonwoven material. Each nonwoven material can be manufactured inline or unwound from a supply roll. In the embodiment illustrated in Fig. In the embodiment illustrated in Figure 5, the first nonwoven material 30 is unwound from a supply roll 62, while the second nonwoven material 30a is unwound from a supply roll 62a. As shown, the nonwoven materials 30 and 30a are arranged adjacent to the film 10 and bonded to the film.

[0118] Although other methods such as adhesive bonding, ultrasonic bonding, pressure bonding and / or needle perforation may be used, in some implementations, thermal bonding techniques are used to laminate the nonwoven web material to the elastic film 10. In Fig.5, the materials 30 and 30a are directed to a nip defined between rollers 58 for lamination to the elastic film 10. One or both of the rollers 58 may contain a plurality of raised bonding elements and / or be heated. During lamination, the elastic film 10 is fusion-bonded to the nonwoven web materials 30 and 30a at a plurality of discrete bonding locations. That is, the elastomeric polymer(s) of the film 10 are softened and / or melted so that they can physically enclose the fibers of the nonwoven web materials 30 and 30a. The elastic film 10 may have a certain tackiness so that it also adheres to the fibers during lamination. The resulting laminate 32 is shown, for example, in Fig. 6, which is a block diagram of an elastomeric laminate.

[0119] The resulting laminate 32 may then be wound and stored on a take-up roll 60. Optionally, the laminate 32 may be held under tension, for example, using the same linear speed for roll 60 as the speed of one or more of the stretch rolls 46. However, the composite 32 may be allowed to contract slightly before being wound onto the take-up roll 60. This may be achieved by using a slower linear speed for roll 60.

[0120] Because the elastic film 10 is tensioned prior to lamination in some implementations, after the tension is released, it will retract to its original machine direction length and become shorter in the machine direction, thereby bunching up or forming wrinkles in the laminate 32. The resulting elastic laminate 32 will therefore be extensible in the machine direction to such an extent that the wrinkles or bunches in the laminate 32 can be pulled back flat and subsequently further stretched due to the extensible nature of the nonwoven web 30, as described above, allowing the elastic film 10 to stretch and even stretch beyond its tensioned length in the machine direction. Furthermore, this extensible laminate 32 (e.g., the nonwoven web 30 bonded to the film 10) may be extensible or elastomeric in the cross-machine direction, since the extensible nonwoven web 30 (and the film 10) can accommodate such biaxial stretching (i.e.,Allow stretching in the machine and cross-machine directions).

[0121] In some implementations, the laminate 32 may be mechanically stretched to increase extensibility in the cross machine and / or machine directions. In one implementation, the laminate 32 may be passed through two or more rolls having grooves in the CD and / or MD directions. Such grooved satellite / anvil roll assemblies are described in U.S. Patent Application Nos. 2004 / 0110442 to Rhim, et al. and 2006 / 0151914 to Gerndt, et al., which are incorporated herein by reference in their entirety for all purposes. For example, the laminate 32 may be passed through two or more rolls having grooves in the CD and / or MD directions. The grooved rolls may be made of steel or another hard material (such as hard rubber).

[0122] In addition to the grooved rolls described above, other techniques may be used to mechanically stretch the laminate 32 in one or more directions. For example, the laminate 32 may be passed through a tenter frame that stretches the laminate 32. Such tenter frames are well known in the art and are described, for example, in U.S. Patent Application No. 2004 / 0121687 to Morman, et al. The laminate 32 may also be necked. Suitable necking techniques are described in U.S. Pat. Nos. 5,336,545, 5,226,992, 4,981,747, and 4,965,122 to Morman, and in U.S. Patent Application Publication No. 2004 / 0121687 to Morman, et al., which are incorporated herein by reference in their entirety for all purposes.

[0123] The laminate 32 described above can be used in a variety of applications. As mentioned above, the laminate 32 can be used, for example, in an absorbent article.

[0124] Elastic laminates made according to the present disclosure can exhibit an excellent balance of properties, namely excellent softness combined with high strength properties. For example, the elastic laminate can exhibit an average burst strength of greater than about 1800 g. f , such as more than about 1900 g f , such as more than about 2000 g f , such as more than about 2200 g f , such as more than about 2400 g f , such as more than about 2600 g f , such as more than about 2800 g f , such as more than about 3000 g f and generally less than about 5000 g f have.

[0125] The laminate may also have a yield strength at 2000 g in the machine direction of greater than 170%, such as greater than about 175%, and generally less than about 225%. In the cross direction, the laminate may have a yield strength at 2000 g of about 25% to about 70%, such as about 45% to about 70%. The laminate may have an average stress at 50% elongation in the machine direction of greater than about 320 g. f , such as more than about 350 g f , such as more than about 370 g f , and generally less than about 420 g f , such as less than about 400 g f In the transverse direction, the average load at 50% elongation can be more than about 1500 g f , such as more than about 1600 g f , such as more than about 1700 g f , such as more than about 1800 g f and generally less than about 2200 g f be.

[0126] The average elongation at break of the laminate may be greater than about 5.3%, such as greater than about 5.4%, such as greater than about 5.5%, such as greater than about 5.6%, and generally less than about 6%, such as less than about 5.9%. The average energy-to-peak stress of the elastic laminate may generally be greater than about 4000 gf·cm, such as greater than about 4100 gf·cm, such as greater than about 4200 gf·cm, such as greater than about 4300 gf·cm, and generally less than about 7000 gf·cm.

[0127] The elastic laminate may also exhibit excellent air permeability properties. For example, the laminate may exhibit an air permeability of greater than about 35 cfm, such as greater than about 45 cfm, such as greater than about 55 cfm, such as greater than about 60 cfm, such as greater than about 65 cfm, such as greater than about 70 cfm, and generally less than about 200 cfm.

[0128] With respect to hand feel, the laminate may have an average drape coefficient of less than about 55, such as less than about 45, such as less than about 35, such as less than about 25, such as less than about 15, and generally greater than about 10.

[0129] All of the above physical properties can be achieved with a single-sided or double-sided elastic laminate made according to the present disclosure having a basis weight of less than about 40 g / m 2 , such as less than about 35 g / m 2 , such as less than about 30 g / m 2 , such as less than about 25 g / m 2 , such as less than about 23 g / m 2 , such as less than about 20 g / m 2 , such as less than about 18 g / m 2 , such as less than about 16 g / m 2 , such as less than about 14 g / m 2 and more than about 12 g / m 2 can be achieved.

[0130] In one embodiment, the present disclosure relates to a nonwoven material comprising a strength-providing layer comprising spunbond fibers randomly arranged to form a web; the spunbond fibers may have a denier of less than about 2, such as less than about 1.1, and may be made of a non-elastomeric polymer. The nonwoven material may also comprise a softness-enhancing layer comprising spunbond fibers randomly arranged to form a web; the softness-enhancing layer may comprise a top layer of the nonwoven material, wherein the spunbond fibers included in the softness-enhancing layer comprise elastomeric fibers.

[0131] In one embodiment, the nonwoven material contains two or more strength-promoting layers. In one embodiment, the nonwoven material contains two or more softness-promoting layers. In one embodiment, the nonwoven material contains two or more softness-promoting layers and two or more strength-promoting layers.

[0132] In any of the above embodiments, the strength-providing layer(s) may be present with respect to the softness-enhancing layer(s) in a weight ratio of about 1:4 to about 4:1, such as about 1:3 to about 3:1, such as about 1:3 to about 1.5:1, such as about 1:2 to about 1.1:1.

[0133] In one embodiment, any of the above-described embodiments of the nonwoven material can be incorporated into an elastomeric laminate. In one embodiment, the laminate comprises an elastic backing attached to the nonwoven material. In one embodiment, the backing comprises an elastic film having a first surface and a second surface. In one embodiment, the nonwoven material is attached to the first surface of the elastic film. In another embodiment, a first nonwoven material is attached to the first surface of the elastic film and a second nonwoven material is attached to the second surface of the elastic film. In one embodiment, the strength-providing layer of the nonwoven material(s) can be attached to the elastic film, and the softness-enhancing layer(s) can form an outer surface of the laminate.

[0134] The present disclosure will be better understood by reference to the following examples. Test procedureAir permeability test

[0135] The air permeability test measures the air flow rate through a known dry area of ​​the specimen. The air permeability of each specimen was measured using a Textest FX3300 air permeability tester available from Schmid Corporation, with offices in Spartanburg, SC.

[0136] A specimen was cut from each test sample and placed so that the specimen extended beyond the clamping area of ​​the air permeability test fixture. The specimens were obtained from areas of the sample free of folds, pucker lines, perforations, creases, and / or distortions that would distinguish them from the rest of the test material.

[0137] The tests were conducted in a standard laboratory atmosphere of 23 ±1 °C and 50 ±2% relative humidity. The instrument was turned on and allowed to warm up for at least 5 minutes before testing any specimens. The instrument was calibrated according to the manufacturer's guidelines prior to analyzing the test material. The instrument's pressure sensors were reset to zero by pressing the zero reset button on the instrument. Before testing, and between specimens or specimens as necessary, the dust filter screen was cleaned according to the manufacturer's instructions. The following specifications were chosen for data collection: (a) Unit of measurement: cubic feet per minute (cfm); (b) Test pressure: 125 Pascals (0.5 inch or 12.7 mm water column); and (c) Test head: 38 square centimeters (cm 2 ). Since the test results obtained with probes of different sizes are not always comparable, samples to be compared should be tested with the same probe.

[0138] The zero reset button was pressed before each test series or when the red light on the device was displayed. The test head was open (no test piece present) and the vacuum pump was completely stopped before the zero reset button was pressed.

[0139] Each test specimen was placed over the lower test head of the instrument. The test was initiated by manually pressing the clamping lever until the vacuum pump started automatically. The range indicator light on the instrument was stabilized in the green or yellow range using the RANGE knob. After the digital display stabilized, the air permeability of the test specimen was displayed and the value recorded. The test procedure was repeated for 10 specimens of each sample, and the average value for each sample was recorded as the air permeability. Burst strength test

[0140] The burst strength test measures the force required to burst (i.e., break) a test specimen using a constant strain rate (CRE) tensile tester. The burst strength of each specimen was measured using an MTS Criterion Model 42 tensile tester from MTS Systems Corporation.

[0141] A 4 in x 4 in (101.6 mm x 101.6 mm) specimen was cut from each test sample and placed in a clamp with a circular opening defining the test area. An indenter assembly with a smooth, spherical probe tip was placed perpendicular to and centered below the circular test area. The indenter assembly consisted of a spherical probe tip attached to the end of a sleeve that was secured to the tensile tester with a locknut. The burst strength test was conducted in accordance with TAPPI T570 pm-00 at a test speed of 6 inches per minute and a 50 Newton load cell. The indenter assembly was raised at the specified test speed so that the spherical probe tip contacted the specimen until it reached the point of failure and eventually penetrated it.The maximum force applied by the indenter assembly at the time of specimen rupture was recorded as the burst strength in gram-force (gf). The average value of 10 test specimens for each specimen was recorded. Yield strength test.

[0142] "Yield strength" means a ratio determined by taking the difference between the unstretched dimension of a stretchable laminate and the maximum stretched dimension of a stretchable laminate when a given clamping force is applied and dividing this difference by the unstretched dimension of the stretchable laminate. When yield strength is expressed as a percentage, this ratio is multiplied by 100. For example, a stretchable laminate with an unstretched length of 5 inches (12.7 cm) and a maximum stretched length of 10 inches (25.4 cm) will have a yield strength (at 2000 grams) of 100 percent when a force of 2000 grams is applied. Yield strength may also be referred to as "maximum non-destructive elongation." Yield strength values ​​are given here at a load of 2000 grams unless otherwise noted.For the yield strength test, a 3-inch by 7-inch (7.62 cm by 17.78 cm) specimen, the larger of which is the machine direction, the cross direction, or any direction in between, is placed in the jaws of a Sintech machine with a 5-cm gap between the jaws. The specimen is then pulled to a stopping load of 2000 g at a crosshead speed of approximately 20 inches / min (50.8 cm / min). It is desirable for the stretchable laminate material of the present invention to have a yield strength value between about 30 and 400 percent, alternatively between about 50 and 300 percent, or still further alternatively between about 80 and 250 percent. The yield strength test is conducted in the stretch direction. An intermediate load at 50% elongation can also be tested using the above procedure. Draping coefficient test

[0143] The Cusick drape test can be performed using any suitable drape test device to obtain a drape coefficient. Commercially available drape test devices include the TF118 test device marketed by Testex of Dongguam, China, or the Model 665 test device marketed by James H Heal & Co. of Halifax, England. The drape test can be performed according to ISO Test 9073-9 (2008). TS7 and TS750 tests

[0144] TS7 and TS750 values ​​were measured using an EMTEC Tissue Softness Analyzer ("TSA") (Emtec Electronic GmbH, Leipzig, Germany). The TSA consists of a rotor with vertical blades that rotate on the test piece and apply a defined contact pressure. The contact of the vertical blades with the test piece creates vibrations that are recorded by a vibration sensor. The sensor then sends a signal to a PC for processing and display. The signal is displayed as a frequency spectrum. To measure TS7 and TS750 values, the blades are pressed against the sample with a load of 100 mN and the blades rotate at 2 revolutions per second.

[0145] To measure TS7 and TS750 values, two different frequency analyses are performed. The first frequency analysis is performed in the range from approximately 200 Hz to 1000 Hz, with the amplitude of the peak occurring at 750 Hz being recorded as the TS750 value. The TS750 value represents the surface smoothness of the sample. A high amplitude peak correlates with a rougher surface. A second frequency analysis is performed in the range from 1 to 10 kHz, with the amplitude of the peak occurring at 7 kHz being recorded as the TS7 value. The TS7 value represents the softness of the sample. A lower amplitude correlates with a softer sample. Both TS750 and TS7 values ​​have the units dB V 2 rms. Tension and stress

[0146] The tensile properties of nonwoven materials were determined essentially according to ASTM D-5034.

[0147] Specifically, a nonwoven web sample was cut or otherwise sized to 25 millimeters (width) x 127 millimeters (length). A constant strain rate type tensile tester was used. The tensile testing system was a Sintech tensile tester available from Sintech Corp., Cary, NC. To assist with testing, the tensile tester was equipped with TESTWORKS 4.08B software from MTS Corporation. A suitable load cell was selected so that the tested value ranged from 10 to 90% of the full scale load. The sample was held between clamps having front and back dimensions measuring 25.4 millimeters x 76 millimeters. The gripping surfaces were rubberized, and the longer dimension of the grip was perpendicular to the direction of tension. The grip pressure was maintained pneumatically at a pressure of 40 pounds per square inch.The tensile test was carried out at a speed of 300 millimeters per minute with a gauge length of 10.16 centimeters and a fracture sensitivity of 40%.

[0148] Five specimens were tested. Stress was determined at a force of 2000 g and strain at 50% in both the machine direction and the cross-machine direction. The results of the five specimens were averaged. Martindale Abrasion

[0149] This test measures the relative abrasion resistance of a specimen according to Worldwide Strategic Partners (“WSP”) Standard Test No. 20.5 (08). A circular specimen with a diameter of 165 mm ± 6.4 mm and an area of ​​18,258 mm 2is subjected to a required number of cycles (10 or 60) with an abrasive under a pressure of 9 kilopascals (kPa). The abrasive is a 36 inch by 4 inch by 0.05 thick, glass fiber reinforced silicone rubber wheel with a rubber surface hardness 81A Durometer, Shore A of 81 ± 9. The specimen is examined for the presence of surface fraying (fiber abrasion), pilling (small fiber remnants), roping, delamination, or holes and assigned a numerical rating of 1, 2, 3, 4, or 5 based on comparison with a set of similarly numbered standard photographs, with "1" indicating the greatest wear and "5" the least. The test is conducted using a Martindale Wear and Abrasion Tester, such as Model No. 103 or 403 from James H. Heal & Company, Ltd. of West Yorkshire, England. Thermal conductivity and thermal effusivity

[0150] The thermal effusivity of the sample was measured using a C-Therm TCi thermal conductivity analyzer according to ASTM D7984-16 Standard ("Test Method for Measurement of Thermal Effusivity of Fabrics with a Modified Transient Plane Source (MTPS) Instrument"). The standard C-Therm TCi thermal conductivity analyzer uses the Modified Transient Plane Source (MTPS) technique to characterize the thermal conductivity and effusivity of materials.

[0151] It uses a one-sided thermal reflection sensor at the interface, which applies a short-term constant heat source to the sample. Example No. 1

[0152] Various elastic laminates were prepared according to the present disclosure, wherein an elastic backing comprising a strength-providing layer and a softness-enhancing layer was applied to each top side of the backing. The strength-providing layer was applied to the film backing.

[0153] The samples prepared according to the present disclosure were compared to a similar laminate containing only elastomeric spunbond fibers as a cover layer on each side and an elastomeric laminate containing low denier polypropylene spunbond fibers as a cover layer on each side.

[0154] Specifically, the following samples were prepared. In each sample, the elastic carrier was a film. The film accounted for approximately 28% to approximately 37% of the basis weight of the laminate. Sample No. 1: Each topsheet layer contained a strength-building layer and a softness-enhancing layer. The strength-building layer was attached to the film and comprised a 4 g / m 2 Spunbonded nonwoven web made of polypropylene fibers with a denier of approximately 1. The softness-enhancing layer was a 6 g / m 2 A spunbonded bicomponent fiber web with an elastomeric core surrounded by a polyethylene sheath. The core contained two elastomeric polymers (a VERSIFY polymer and a VISTAMAXX polymer), a metallocene-catalyzed polypropylene, and a secondary amide. The laminate was point-bonded with a bonding pattern occupying approximately 15% to 17% of the surface area. Sample No. 2: The same setup as Sample No. 1 Sample No. 3: The same structure as sample No. 1, except that the strength-forming layer had a basis weight of 5 g / m 2and the softness-enhancing layer had a basis weight of 8.5 g / m 2 . Sample No. 4: The top layer attached to the elastic backing consisted only of the softness-enhancing layer as described in Sample No. 1. The top layer on each side of the film had a basis weight of 17 g / m 2 on. Sample No. 5: The cover layer attached to the elastic carrier consisted only of the strength-forming layer, as described in Sample No. 1. The cover layer on each side of the film had a basis weight of 10 g / m 2 on.

[0155] The above samples were tested for various physical properties and the following results were obtained. Table No. 1 Sample No. Average basis weight (g / m 2 ) Average air permeability (cfm) 1 89,30 74,26 2 86,19 69,90 3 102,91 36,56 4 128,57 18,00 5 88,82 100,24 Table No. 2 Sample No. Average yield strength at 2000 gf in machine direction (%) Average yield strength at 2000 gf in transverse direction (%) Average load at 50% elongation in machine direction (gf) Average load at 50% elongation in the transverse direction (gf) 1 181,03 50,83 343,60 1957,80 2 175,90 53,42 348,30 1877,36 3 175,92 33,18 399,00 nz 4 226,73 71,96 451,30 1335,70 5 165,35 17,74 304,70 nz Table No. 3 Sample No. Average burst strength (gf) Average elongation at break (%) Average energy-to-peak load (gf·cm) 1 2019,30 5,90 4483,70 2 1923,70 5,80 4111,80 3 2519,90 5,60 4971,50 4 1596,90 6,10 3913,70 5 4693,20 4,90 6930,80 Table No. 4 Sample No. Average TS7 Average TS750 1 5,289 58,325 2 5,660 59,827 3 5,008 85,164 4 3,140 93,339 5 7,970 50,050 Table No. 5 Sample No. Average draping coefficient 1 50,09 2 51,45 3 57,30 4 32,72 5 64,51 Example No. 2

[0156] More elastic laminates made according to the present disclosure generally have the same construction and are made in the same manner as described in Example No. 1 above.

[0157] Samples Nos. 6 to 23 were prepared. Each sample included an elastic backing attached to a cover layer on each side. Samples Nos. 8 to 22 were prepared according to the present disclosure, with each cover layer including a strength-building layer and a softness-enhancing layer. The strength-building layer was attached to the film backing.

[0158] Samples Nos. 6 and 7 contained facesheets composed solely of elastomeric spunbond fibers. Sample No. 23, on the other hand, contained facesheets composed solely of low-denier polypropylene spunbond fibers.

[0159] The elastomeric spunbond fibers and the low-denier polypropylene spunbond fibers had the same construction as described in Example 1. However, Samples 15 and 16 each contained 5 wt.% of an elastomeric polymer in the strength-forming layer fibers (VISTAMAXX polymer).

[0160] The elastic laminates were tested for various properties. The following Tables 6, 7, and 8 show the results. Table No. 6 Sample No. Total surface layer basis weight (g / m 2 ) % strength-forming layer Laminate basis weight (g / m 2 ) Air permeability (cfm) 6 36 0 147,3 2,5 7 34 0 139,3 9,5 8 36 25 143,4 13,0 9 28 25 120,9 18,1 10 28 40 121,0 26,3 11 20 40 98,1 63,4 12 28 40 115,5 20,1 13 28 50 121,9 47,7 14 20 50 88,7 78,2 15 28 50 114,8 49,5 16 28 40 113,7 40,7 17 28 70 130,1 47,8 18 28 70 105,5 57,4 19 20 70 109,8 67,8 20 28 60 111,2 47,5 21 20 60 82,2 63,1 22 28 40 115,6 19,1 23 22 100 90,6 129,8 Table No. 7 Sample No. MD tension at 2000 g (%) MD load at 50% (gf) CD tension at 2000 g (%) CD load at 50% (gf) 6 219,7 413,6 77,0 1162,5 7 210,6 370,8 103,9 811,9 8 177,0 431,4 40,2 Not tested 9 194,3 366,6 68,6 1311,3 10 187,1 345,7 47,7 Not tested 11 201,0 305,3 83,7 1111,0 12 172,0 388,6 43,3 Not tested 13 174,8 327,8 37,2 Not tested 14 179,7 311,2 78,0 1189,3 15 182,9 351,3 35,1 Not tested 16 186,5 355,3 45,9 Not tested 17 180,1 337,2 28,6 Not tested 18 174,0 357,4 27,6 Not tested 19 184,5 294,3 51,7 1935,4 20 176,2 361,6 30,2 Not tested 21 178,7 309,7 60,2 1641,8 22 179,0 379,9 26,5 Not tested 23 166,8 261,4 17,9 Not tested Table No. 8 Sample No. Burst peak load (gf) Burst energy up to peak load (gf cm) Fracture tip strain (cm) TS7 TS750 Draping s-coefficient Martindal abrasion (cycles) Thermal conductivity, k (W / mK) Thermal effusivity, e (Ws1 / 2 m-2K-1 ) 6 1574,7 3778,4 6,3 3,7 109,2 29,1 Not tested Not tested Not tested 7 1407,4 3230,1 6,3 3,3 99,5 26,4 2 0,044 112,5 8 2704,6 5799,6 6,1 3,9 150,7 45,9 Not tested Not tested Not tested 9 2172,8 4892,6 6,5 3,3 101,2 38,2 2 0,040 86,2 10 2289,9 5076,1 6,1 3,5 101,7 46,7 2,25 0,041 93,9 11 1648,2 3668,9 6,3 3,7 55,1 30,1 2,5 0,039 79,2 12 2802,0 6224,9 6,3 3,4 113,2 46,5 4 0,038 75,5 13 2313,4 4770,9 5,7 3,7 85,7 48,0 3,5 0,039 79,2 14 1806,6 4006,0 6,4 3.6 51,6 33,3 2,5 Not tested Not tested 15 2756,5 6281,9 6,2 3,7 85,6 48,3 Not tested Not tested Not tested 16 2449,4 5621,3 6,4 3,7 94,0 45,8 Not tested Not tested Not tested 17 2583,6 5440,8 5,6 4,2 95,1 53,3 Not tested Not tested Not tested 18 2583,6 5440,8 5,6 4,0 88,4 55,1 3,5 0,037 67,7 19 2673,9 5167,5 5,5 3,9 62,3 44,7 2,5 0,039 77,7 20 2013,4 4296,2 6,0 3,9 91,0 52,2 3,75 0,039 80,3 21 2643,1 5179,7 5,6 3,9 61,7 45,6 2,75 Not tested Not tested 22 1950,2 4155,2 6,0 3,1 90.0 53,4 Not tested Not tested Not tested 23 4691,5 6949,7 4,9 5,0 52,2 57,2 5 0,036 56,4

[0161] As shown in the above examples, laminates made according to the present disclosure exhibit an excellent combination of properties.

[0162] These and other modifications and variations of the present invention may be made by one skilled in the art without departing from the spirit and scope of the present invention, as particularly pointed out in the appended claims. Furthermore, it is to be understood that aspects of the various embodiments are interchangeable, in whole or in part. Furthermore, those skilled in the art will understand that the foregoing description is merely exemplary and is not intended to limit the invention, as particularly described in the appended claims. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

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[0122] Zitierte Nicht-Patentliteratur

[0000] ISO Test 9073-9 (2008

[0143] Test Method for Measurement of Thermal Effusivity of Fabrics with a Modified Transient Plane Source (MTPS) Instrument

[0150]

Claims

A nonwoven material comprising:a strength-providing layer comprising spunbond fibers randomly arranged to form a web, wherein the spunbond fibers have a denier of less than about 2 and are made from a non-elastomeric polymer; anda softness-enhancing layer comprising spunbond fibers randomly arranged to form a web, wherein the softness-enhancing layer comprises a top layer of the nonwoven material, wherein the spunbond fibers included in the softness-enhancing layer comprise elastomeric fibers. Nonwoven material according to claim 1, wherein the nonwoven material contains two or more strength-forming layers. Nonwoven material according to claim 1, wherein the nonwoven material contains two or more softness-enhancing layers. Nonwoven material according to claim 1, wherein the nonwoven material contains two or more softness-enhancing layers and two or more strength-forming layers. Nonwoven material according to one of the preceding claims, wherein the spunbond fibers contained in the strength-forming layer are made of a polypropylene polymer. The nonwoven material of claim 5, wherein the polypropylene polymer comprises at least about 70 wt.%, such as at least about 80 wt.%, such as at least about 90 wt.% of the spunbond fibers contained in the strength-forming layer. A nonwoven material according to any one of the preceding claims, wherein the spunbond fibers contained in the strength-forming layer have a denier of less than about 1.3, such as less than about 1, such as less than about 0.9, such as less than about 0.

85. A nonwoven material according to any one of the preceding claims, wherein the spunbond fibers contained in the softness-enhancing layer comprise elastomeric bicomponent fibers, the bicomponent fibers comprising a core surrounded by a sheath. Nonwoven material according to claim 8, wherein the core of the bicomponent fibers comprises a polypropylene-based elastomer and a secondary amide. The nonwoven material of claim 9, wherein the polypropylene-based elastomer comprises an ethylene copolymer, α-olefin copolymer, or a combination thereof. Nonwoven material according to claim 9 or 10, wherein the sheath comprises a non-elastomeric polymer. Nonwoven material according to one of claims 9 to 11, wherein the sheath comprises a polyethylene polymer. Nonwoven material according to one of claims 9 to 11, wherein the secondary amide is a fatty acid amide. Nonwoven material according to one of claims 9 to 13, wherein the secondary amide has a structure with one of the following: where R 14 , R 15 , R 16 and R 18 independently from C 7 -C 27 -alkyl groups and C 7 -C 27 -alkenyl groups are selected; and R 17 from C 8 -C 28 -alkyl groups and C 8 -C 28 -alkenyl groups is selected. Nonwoven material according to one of claims 9 to 14, wherein the core contains a second elastomer. Nonwoven material according to one of the preceding claims, wherein the nonwoven material has a basis weight of about 5 g / m2 to about 170 g / m2. Nonwoven material according to one of claims 1 to 15, wherein the nonwoven material has a basis weight of about 9 g / m2 to about 30 g / m2. A nonwoven material according to any one of the preceding claims, wherein the strength-providing layer is present in a weight ratio of about 1:4 to about 4:1, such as about 1:3 to about 3:1, such as about 1:3 to about 1.5:1, such as about 1:2 to about 1.1:1, relative to the softness-enhancing layer. An elastomeric laminate comprising a nonwoven material according to any one of the preceding claims. The elastomeric laminate of claim 19, wherein the laminate comprises a backing attached to the nonwoven material, the backing comprising an elastic film having a first surface and a second surface, and the strength-forming layer is attached to the first surface of the elastic film. The elastomeric laminate of claim 19 or 20, wherein the nonwoven material has a basis weight of about 9 g / m2 to about 30 g / m2 and wherein the elastomeric laminate has a burst strength of greater than about 1800 gf, such as greater than about 2200 gf, such as greater than about 2500 gf, such as greater than about 2800 gf, such as greater than about 3000 gf. The elastomeric laminate of claim 19, 20 or 21, wherein the elastomeric laminate has an average STS at 2000 g in a machine direction of greater than about 170 gf, such as about greater than about 175 gf, and less than about 225 gf. The elastomeric laminate of claim 20, wherein a second nonwoven material is attached to the second surface of the backing and wherein the strength-forming layer of the second nonwoven material is attached directly to the second surface of the elastic film. The elastomeric laminate of claim 19, 20, 21, 22 or 23, wherein the elastomeric laminate has an average TS7 of less than about 6, such as less than about 5.8, such as less than about 5.5, and greater than about 2. The elastomeric laminate of claim 19, 20, 21, 22, 23 or 24, wherein the elastomeric laminate has an average drape coefficient of less than about 55, such as less than about 45, such as less than about 35, such as less than about 25, such as less than about 15, and generally greater than about 10.

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