Nonwoven materials with high strength and soft touch and laminates

Abstract

A nonwoven material having an excellent balance between strength and softness is disclosed. The nonwoven material can be made from a spunbond layer and can include at least one strength building layer in combination with at least one softness enhancing layer. In one aspect, the nonwoven material can be incorporated into an elastomeric laminate for use in an absorbent article.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on and claims priority from U.S. Provisional Patent Application Serial No. 63 / 411,768, filed on September 30, 2022, which is incorporated herein by reference in its entirety. Background Art

[0003] Spunbond nonwoven fabrics include a bonded web of continuous filaments formed by extruding a molten thermoplastic polymer from a plurality of fine capillaries into molten filaments. The molten filaments are quenched to at least partially solidify them, and then thinned by one or more high-speed air streams to reduce their diameter. For example, spunbond filament nonwoven webs and methods of making the same are disclosed in US4340563 to Appel et al., US5382400 to Pike et al., US8246898 to Conrad et al., and US8333918 to Lennon et al.

[0004] Spunbond filament nonwoven webs are commonly used in a wide range of products. The reason for this wide and diverse use is partly related to the ability of spunbond filament nonwoven webs to provide a desired combination of properties. In addition, the cost of manufacturing spunbond filament webs is relatively low compared to other materials with similar properties such as traditional knitted fabrics or woven fabrics. Therefore, it has been found that spunbond filament nonwoven webs are particularly useful for manufacturing products that are disposable or limited in use; for example, absorbent personal care products, wipes, protective clothing, geotextiles, tarpaulins, etc.

[0005] The properties of spunbond webs can be altered by changing the composition of the polymer used to produce the web. For example, producing a spunbond web from an elastomeric material can produce a web with a soft hand and excellent drape characteristics. However, elastic spunbond webs tend to lack strength and durability compared to spunbond webs made from other polymer materials.

[0006] In view of the above, there is a need for a nonwoven web that not only has a soft hand but also has excellent strength properties. There is also a need for an elastic laminate that can incorporate a nonwoven web as described above. Summary of the invention

[0007] Generally speaking, the present disclosure relates to producing nonwoven webs having a good balance of softness and strength. For example, in one aspect, a nonwoven web is made according to the present disclosure, which includes a face fabric made from a soft elastic spunbond web. The nonwoven web also includes at least one other strength building layer, which can also be made from a spunbond web. In one embodiment, the strength building layer can be produced from a fine fiber polymer layer. The nonwoven web is particularly suitable for producing elastomeric laminates, wherein the strength building layer is disposed against an elastic film, and the elastic layer forms a top layer of the laminate, which has soft, cloth-like properties.

[0008] For example, in one embodiment, the present disclosure relates to a nonwoven material. The nonwoven material includes a strength construction layer, which includes spunbond fibers randomly arranged to form a web. The spunbond fibers have a denier less than about 2 and are made of a non-elastomeric polymer. For example, the non-elastomeric polymer can be a polypropylene polymer, and can account for at least about 70% of the strength construction layer, such as at least about 80%, such as at least about 90%. The denier of the spunbond fibers included in the strength construction layer can 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.

[0009] The nonwoven material also includes a softness enhancing layer, which includes spunbond fibers randomly arranged to form a net. The softness enhancing layer can be incorporated into the nonwoven material to form the top layer of the material. In one aspect, the softness enhancing layer can be bonded to the strength building layer. The spunbond fibers in the softness enhancing layer can include elastomeric fibers. For example, the elastomeric fibers can be made of elastomeric bicomponent fibers, which include a core surrounded by a skin. In one embodiment, the core of the bicomponent fiber can be formed by the elastomer of genetic polypropylene alone, or formed in combination with a secondary amide. Elastomers based on polypropylene can include ethylene copolymers, alpha-olefin copolymers, or combinations thereof. On the other hand, the skin can include non-elastomeric polymers. For example, the skin can be made of polyethylene polymers.

[0010] As mentioned above, the core may comprise a secondary amide, which may be a fatty acid amide. For example, the secondary amide may have the following chemical structure:

[0011]

[0012] in,

[0013] R 14 , R 15 , R 16 and R 18 Independently selected from C7-C 27 Alkyl groups and C7-C 27 an alkenyl group; and

[0014] R17 Selected from C8-C 28 Alkyl groups and C8-C 28 Alkenyl group.

[0015] In one aspect, the elastomeric bicomponent fibers of the softness-enhancing layer may include a core made from at least two elastomeric polymers, alone or in combination with a secondary amide.

[0016] The basis weight of the nonwoven material manufactured according to the disclosure can change according to specific application and required result.Generally speaking, the basis weight of the nonwoven material can be any value of about 5gsm to about 300gsm, including all 1gsm increments therebetween.In certain embodiments, the basis weight can be about 5gsm to about 170gsm, such as about 9gsm to about 20gsm.The weight ratio between the strength construction layer in the nonwoven material and the softness reinforcing layer can be about 1:3 to about 1.5:1, such as about 1:2 to about 1.1:1.

[0017] The present disclosure also relates to an elastomeric laminate comprising a nonwoven material as described above. In one aspect, the elastomeric laminate can include an elastic backing that can be made of an elastic film or a plurality of parallel elastic filaments or ribbons. In one aspect, a strength building layer can be adhered to the backing. In another aspect, a softness enhancing layer can form the outer surface of the elastomeric laminate.

[0018] Elastomer laminates manufactured according to the present disclosure can have an excellent balance of strength and soft properties. For example, the elastomeric laminate can have a burst strength greater than about 1800g, such as greater than about 2200g, such as greater than about 2500g, such as greater than about 2800g, such as greater than about 3000g, at a basis weight of about 20gsm to about 40gsm. Laminates can have an average stretch to stop value greater than about 170%, such as greater than about 175%, and generally less than about 225% in the longitudinal direction under a load of 2000g. In addition to the above characteristics, laminated materials can also show excellent soft properties. For example, the TS7 of the laminate can be less than about 6, such as less than about 5.8, such as less than about 5.5, and generally greater than 2.

[0019] Other features and aspects of the disclosure are discussed in greater detail below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The disclosure that makes the present disclosure comprehensive and enabling is more particularly set forth in the remainder of the specification and with reference to the accompanying drawings, in which:

[0021] 1a and 1b are exemplary fibers for nonwoven materials made according to the present disclosure;

[0022] Figure 2is an exemplary schematic diagram of an apparatus for forming a stretchable fabric;

[0023] Figure 3 is an example of a schematic diagram of an apparatus for forming a strength building layer;

[0024] Figure 4 is an exemplary schematic diagram of an apparatus for forming a nonwoven material according to the present disclosure;

[0025] Figure 5 is an example schematic diagram of an apparatus for forming an elastic laminate according to the present disclosure; and

[0026] Figure 6 is an example cross-sectional view of an elastic laminate that can be made according to the present disclosure.

[0027] Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention.

[0028] definition

[0029] As used herein, the terms "about", "approximately" or "substantially" when used to modify a value indicate that the value can be increased or decreased by 10% (e.g., such as 7.5%, 5%, such as 4%, such as 3%, such as 2%, such as 1%) and remain within the disclosed aspects. In addition, the term "substantially free" when used to describe the amount of a substance in a material is not limited to being completely or completely free, and can be equivalent to the lack of any perceptible or detectable amount of the listed substance in the material. Thus, for example, when the amount of a substance in a material is less than the precision of an industry-recognized instrument or test for measuring the amount of a substance in a material, the material is "substantially free" of the above-mentioned substance. In certain example embodiments, when the amount of a substance in a 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, the material can be "substantially free" of the above-mentioned substance.

[0030] As used herein, the terms "elastomeric" and "elastic" refer to a material that can stretch in at least one direction (such as the CD or MD direction) upon application of a stretching force and contract / return to approximately its original dimensions upon release of the stretching force. For example, a stretched material may have a stretched length that is at least 50% greater than its relaxed, unstretched length and will return to within at least 50% of its stretched length upon release of the stretching force. A hypothetical example would be a one (1) inch sample of material that can be stretched to at least 1.50 inches and will return to a length of no more than 1.25 inches upon release of the stretching force. Advantageously, the material contracts or recovers at least 50% of the stretched length, and even more advantageously at least 80%.

[0031] As used herein, the term "fiber" generally refers to an elongated extrudate that can be formed by passing a polymer through a forming orifice such as a die. Unless otherwise indicated, the term "fiber" includes discontinuous fibers (e.g., stabilized fibers) and substantially continuous filaments having a certain length. Substantially continuous filaments may, for example, have a length much greater than their diameter, such as a length to diameter ratio ("aspect ratio") greater than about 15,000 to 1 and in some cases greater than about 50,000 to 1.

[0032] As used herein, the term "extensible" generally refers to a material that stretches or extends about 50% or more, in some aspects about 75% or more, in some aspects about 100% or more, and in some aspects about 200% or more of its relaxed length or width in the direction of an applied force (e.g., CD or MD direction).

[0033] As used herein, the terms "necked" and "necked material" generally refer to any material that has been stretched in at least one dimension (e.g., longitudinally) to reduce its transverse dimension (e.g., transversely) so that the material can be pulled back to its original width when the stretching force is removed. Necked materials generally have a higher basis weight per unit area than unnecked materials. When the necked material is pulled back to its original width, it should have approximately the same basis weight as the unnecked material. This is different from the orientation of the film in which the film is thinned and the basis weight is reduced. The necking process generally involves unwinding the material from a supply roll and passing the material through a brake nip roll assembly driven at a given linear speed. A take-up roll or nip running at a higher linear speed than the brake nip roll stretches the material and creates the tension required to elongate and neck the material.

[0034] As used herein, the term "nonwoven web" generally refers to a web having a structure of individual fibers or threads that are interlayered but not in an identifiable manner (such as in a knitted fabric). Examples of suitable nonwoven fabrics or webs include, but are not limited to, meltblown webs, spunbond webs, bonded carded webs, air-laid webs, coformed webs, hydroentangled webs, and the like.

[0035] As used herein, the term "meltblown web" refers generally to a nonwoven web formed by a process in which a molten thermoplastic material is extruded as molten fibers through a plurality of fine, generally circular die capillaries into a converging high-speed gas (e.g., air) stream, which reduces the diameter of the fibers of the molten thermoplastic material to a microfiber diameter. Thereafter, the meltblown fibers are carried by the high-speed gas stream and deposited on a collecting surface to form a randomly dispersed web of meltblown fibers. Such a process is disclosed, for example, in U.S. Pat. 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 substantially continuous or discontinuous microfibers that are generally less than 10 microns in diameter and are generally tacky when deposited on a collecting surface.

[0036] As used herein, the term "spunbond web" generally refers to a web comprising substantially continuous fibers of small diameter. The fibers are formed by extruding molten thermoplastic material from a plurality of fine, usually circular capillaries of a spinneret having the diameter of the extruded fibers and then rapidly attenuated by, for example, eductive drawing and / or other well-known spunbonding mechanisms. The preparation of spunbond webs is described and illustrated, for example, in U.S. Pat. No. 4,340,563 to Appel et al., U.S. Pat. No. 3,692,618 to Dorschner et al., U.S. Pat. No. 3,802,817 to Matsuki et al., U.S. Pat. No. 3,338,992 to Kinney et al., U.S. Pat. No. 3,341,394 to Kinney et al., U.S. Pat. No. 3,502,763 to Hartman et al., U.S. Pat. No. 3,502,538 to Levy, U.S. Pat. No. 3,542,615 to Dobo et al., and U.S. Pat. No. 5,382,400 to Pike et al., which are incorporated herein by reference in their entirety for all purposes. Spunbond fibers are generally not tacky when deposited onto a collecting surface. Spunbond fibers may sometimes have a diameter of less than about 40 microns, and are typically between about 5 and about 20 microns.

[0037] As used herein, the term "machine direction" or "MD" generally refers to the direction in which a material is produced (eg, the direction in which the material is transported during the formation / manufacturing process of a nonwoven material). The term "cross machine direction" or "CD" refers to the direction perpendicular to the machine direction.

[0038] As used herein, the term "thermal point bonding" generally refers to a process performed, for example, by passing a material between a patterned roll (e.g., a calendar roll) and another roll that may or may not be patterned (e.g., an anvil roll). One or both of the rolls are typically heated.

[0039] As used herein, the term "ultrasonic bonding" generally refers to a process performed, for example, by passing a material between an ultrasonic horn and a patterned roller (e.g., an anvil roller). For example, ultrasonic bonding performed using a stationary horn and a rotating patterned anvil roller is described in U.S. Pat. No. 3,939,033 to Grgach et al., U.S. Pat. No. 3,844,869 to Rust Jr., and U.S. Pat. No. 4,259,399 to Hill, which are incorporated herein by reference in their entirety for all purposes. In addition, ultrasonic bonding performed using a rotating horn and a rotating patterned anvil roller is described in U.S. Pat. No. 5,096,532 to Neuwirth et al., U.S. Pat. No. 5,110,403 to Ehlert, and U.S. Pat. No. 5,817,199 to Brennecke et al., which are incorporated herein by reference in their entirety for all purposes. Of course, any other ultrasonic bonding technology may also be used in the present disclosure.

[0040] As used herein, "continuous filaments" refers to filaments formed in a substantially continuous, uninterrupted manner, having an infinite length and having a high aspect ratio (length to diameter) in excess of about 10,000:1.

[0041] As used herein, the term "polymer" generally includes, but is not limited to, homopolymers, copolymers, such as block, graft, random and alternating copolymers, terpolymers, and the like, as well as blends and modifications thereof. In addition, unless otherwise specifically limited, the term "polymer" shall include all possible geometric configurations of the molecule. These configurations include, but are not limited to, isotactic, syndiotactic and random symmetries.

[0042] As used herein, "ethylene polymer" or "polyethylene" refers to a polymer having greater than 50 mole percent of units derived from ethylene.

[0043] As used herein, "olefin polymer" or "polyolefin polymer" refers to a polymer having greater than 50 mole % of units derived from olefins, including linear, branched, or cyclic olefins.

[0044] "Propylene polymer" or "polypropylene" as used herein refers to polymers having greater than 50 mol% of units derived from propylene.

[0045] As used herein, "personal care articles" refers to any and all articles or products used for personal health or hygiene, including diapers, adult incontinence garments, absorbent pants and absorbent garments, tampons, feminine pads and liners, body wipes (e.g., baby wipes, perineal wipes, hand wipes, etc.), bibs, changing pads, bandages, and components thereof.

[0046] As used herein, "protective article" refers to all articles intended to protect a user or equipment from contact or exposure to external agents, including, for example, masks, protective gowns and aprons, gloves, caps, shoe covers, equipment covers, sterile wraps (e.g., for medical devices), vehicle covers, etc. DETAILED DESCRIPTION

[0047] Those skilled in the art will appreciate that this discussion is merely a description of exemplary embodiments and is not intended to limit the broader aspects of the present disclosure.

[0048] Generally speaking, the present disclosure relates to a nonwoven material with at least two different layers. These layers include at least one strength building layer combined with at least one softness enhancing layer. For example, the strength building layer can be made of a non-elastomeric polymer with relatively fine fibers. On the other hand, the softness enhancing layer can be made of one or more elastomeric materials. The nonwoven material of the present disclosure has multiple uses and applications. For example, in one aspect, the nonwoven material can be combined with or attached to an elastic backing to produce a laminate.

[0049] The nonwoven material manufactured according to the present disclosure provides various advantages and benefits. For example, the nonwoven material is relatively strong due to the strength building layer. In addition, at least one outer layer of the nonwoven material includes a softness enhancing layer that is noticeably soft to the touch. Therefore, the nonwoven material manufactured according to the present disclosure has a unique balance between strength and softness.

[0050] Softness enhancement layer

[0051] As mentioned above, the nonwoven material of the present disclosure generally comprises at least one softness enhancing layer and at least one strength building layer. The softness enhancing layer forms the top surface or outer surface of the nonwoven material. The softness enhancing layer is soft to the touch and can be formulated to have a cloth-like feel.

[0052] As will be described in more detail below, the polymers used to form the softness enhancing layer typically have a softening temperature higher than the temperature imparted during bonding and are ductile or elastic. Thus, these polymers do not substantially soften during bonding, to the extent that the fibers of the softness enhancing layer are said to be 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 about 120°C to about 250°C, and in some embodiments about 130°C to about 200°C can be used. Exemplary high softening point polymers for forming the softness enhancing layer may include, for example, ExxonMobil TM PP3155 (inelastic) and Achieve TM Advanced PP3854 and Dow TMASPUN6850.

[0053] Extensible or elastomeric monocomponent and / or multicomponent fibers can be used to form softness enhancing layers, such as fabrics. Monocomponent fibers are typically formed from a polymer or blend of polymers extruded from a single extruder. Multicomponent fibers are typically formed from two or more polymers extruded from separate extruders (e.g., bicomponent fibers). The polymers may be arranged in substantially constant different zones throughout the cross-section of the fiber. The components may be arranged in any desired configuration, such as skin-core, side-by-side, sandwich, island-in-the-sea, three-island, bull's-eye, or various other arrangements known in the art, and the like. Various methods for forming multicomponent fibers are described in U.S. Pat. No. 4,789,592 to Taniguchi et al., 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., the entireties of which are incorporated herein by reference for all purposes.

[0054] In some embodiments, the polymer of the multi-component fiber of the softness enhancing layer is a spunbond fiber made of a thermoplastic material with different glass transition temperatures or melting temperatures, wherein the temperature at which the first component (e.g., the skin) melts is lower than the temperature at which the second component (e.g., the core) melts. The softening or melting of the first polymer component of the multi-component fiber forms a viscous skeleton structure in the multi-component fiber, which stabilizes the fiber structure when cooled. For example, the multi-component fiber can have a low melting point polymer of about 20% by weight to about 80% by weight, about 40% by weight to about 60% by weight in some embodiments. In addition, the multi-component fiber can have a high melting point polymer of about 80% by weight to about 20% by weight, about 60% by weight to about 40% by weight in some embodiments. In some embodiments, the core of the sheath-core bicomponent fiber comprises a polypropylene homopolymer or copolymer based on a Ziegler-Natta catalyst or a single-site catalyst, and / or the sheath of the sheath-core bicomponent fiber comprises a homopolymer, copolymer, or a mixture thereof from ethylene, propylene, or styrene-derived polymer.

[0055] The basis weight of this softness enhancing layer can change usually, such as from about 5 grams per square meter (" gsm ") to 200gsm, in some embodiments from about 6gsm to about 70gsm, and in some embodiments from about 8gsm to about 35gsm.In one aspect, basis weight is less than about 30gsm, such as less than about 25gsm, such as less than about 20gsm, such as less than about 15gsm, such as less than about 12gsm, such as less than about 10gsm, such as less than about 9gsm, such as less than about 8gsm, such as less than about 7gsm, and greater than about 4gsm.In some embodiments, nonwoven material of the present disclosure can include multiple softness enhancing layers.For example, softness enhancing layers can be adjacent to each other in nonwoven material, and each softness enhancing layer can have identical basis weight or different basis weights.

[0056] As described above, in some embodiments, the nonwoven web is made of monocomponent spunbond fibers. In other embodiments, the nonwoven web is made of bicomponent spunbond fibers. In these embodiments, for example, the bicomponent fibers contain a polyethylene sheath and a polypropylene-based elastomeric core, wherein the core (rather than the sheath) may contain a secondary amide non-blocking additive that may further improve the cloth-like feel of the fabric.

[0057] For example, in one aspect, the secondary amide additive is erucamide, oleamide, oleyl palmitamide, ethylenebisoleamide, stearyl erucamide, or a combination thereof. Of course, it will be appreciated that in one aspect, the secondary amide can be a non-fatty acid amide.

[0058] Regardless of which secondary amide is selected, in one aspect, the secondary amide is present in the core in an amount of about 0.1 wt % to about 10 wt %, such as about 0.25 wt % to about 5 wt %, such as about 0.5 wt % to about 2.5 wt %, such as about 0.6 wt % to about 1.5 wt %, such as about 0.7 % to about 1 %, or any range or value therebetween, based on the weight of the core. Specifically, the disclosure has found that, surprisingly, the secondary amide in the core provides improved spinnability and non-blocking properties to the bicomponent fiber even when used in small amounts in the core.

[0059] In addition, in one aspect, the sheath(s) are formed from one or more ethylene or propylene polymers, such as one or more substantially non-elastomeric ethylene or propylene polymers. Thus, in one aspect, the non-elastomeric polyolefins may 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-vinyl acetate, polyvinyl butyral, acrylic resins (e.g., polyacrylates, polymethyl acrylate, polymethyl methacrylate, etc.), polyamides (e.g., nylon), polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl alcohol, polyurethane, polylactic acid, copolymers thereof, and mixtures thereof, and the like. For example, the sheath may include LLDPE available from Dow Chemical Co., Midland, Mich., such as DOWLEX TM 2517 or DOWLEX TM 2047 or a combination thereof, or Westlake Chemical Corp. of Houston, Tex. In addition, in one aspect, the non-adhesive polyolefin material may be other suitable ethylene polymers, such as those known by the names ASPUN™ (LLDPE) and ATTANE TM (ULDPE) available from Dow Chemical Company. Available from Dow Chemical Company under the name DOWLEX TM (LLDPE), ASPUNTM (LLDPE) and ATTANE TM (ULDPE).

[0060] Additionally, in one 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 those marketed under the name VISTAMAXX TM Propylene-based copolymers (propylene-ethylene copolymer-based plastomers) are commercially available from ExxonMobil Chemical Co. of Houston, Texas (e.g., 2330, 6202, and 6102) under the name FINA TM (e.g., 8573) is commercially available from Atofina Chemicals of Feluy, Belgium under the name TAFMER TM Commercially available from Mitsui Petrochemical Industries and under the name VERSIFY TMCommercially available from Dow Chemical Co. of Midland, Michigan. In addition to the above, the core may also include a non-elastomeric olefin polymer such as a metallocene-catalyzed (single-site-catalyzed) polypropylene polymer in an amount from about 1 wt % to about 40 wt % of the core, such as from about 2 wt % to about 5 wt % of the core.

[0061] Regardless of the elastomer and non-elastomeric polyolefin selected, in one aspect, the core is present in an amount from about 50 wt % to about 97.5 wt %, such as from about 60 wt % to about 95 wt %, such as from about 70 wt % to about 92.5 wt %, such as from about 80 wt % to about 90 wt %, such as from about 82.5 wt % to about 87.5 wt %, or any range or value therebetween, based on the total weight of the elastomeric composition.

[0062] See respectively Figure 1A and Figure 1B , showing a monocomponent fiber 12 and a bicomponent fiber 14 utilizing a sheath / core arrangement. For the bicomponent fiber 14, the core 18 may be formed from a first polymer and the sheath 16 may be formed from a second polymer. Generally, the composition of the monocomponent fiber 12 or the core 18 of the bicomponent fiber may be selected so that the resulting overall material is elastic, cloth-like, drapeable, and soft, and the composition of the sheath 16 of the bicomponent fiber 14 may be selected so that the sheath 16 provides some adhesion properties while not affecting the clothing-like feel of the sheath 16. One such exemplary bicomponent fiber suitable for use in the softness enhancing layer of the present invention is described in U.S. Patent Application No. 63 / 003427, entitled “Elastic Bicomponent Fiber Having Unique Handfeel,” filed on April 1, 2020, the entire contents of which are incorporated herein by reference, including but not limited to the composition of the claimed elastic bicomponent spunbond fiber and the resulting nonwoven formed from the fiber.

[0063] Figure 2 An exemplary process for forming elastomeric, monocomponent or bicomponent spunbond fibers is shown. More specifically, Figure 2The example process in is configured to form substantially continuous fibers (e.g., to make an extensible or elastomeric layer 30). More specifically, in the case of bicomponent fibers, different polymer compositions A (e.g., for the sheath) and B (for the core) are initially supplied to the fiber spinning device 21 to form the bicomponent fibers 23. Alternatively, in the case of monocomponent fibers, only one polymer type (e.g., which may include a blended polymer with or without additives) is supplied to the fiber spinning device 21. Once formed, the fibers 23 pass through the fiber drafting unit 25 and are deposited on the moving forming wire 27. The deposition of the fibers is assisted by a vacuum under the wire provided by the suction box 29, which pulls the fibers 23 down onto the forming wire 27. The forming wire 27 is porous so that the vertical air flow formed by the suction box 29 can cause the fibers to fall. In one aspect of the present disclosure, the flow rate of the air flow can be kept relatively low to enhance the tendency of the fibers 23 to remain oriented in the MD direction. Alternatively, the suction box 29 may include a section extending in the longitudinal direction to disrupt the vertical air flow where the fibers fall onto the moving web, thereby allowing the fibers to have a higher degree of longitudinal orientation. An example of such technology is described in, for example, US Pat. No. 6,331,268.

[0064] Of course, other techniques can also be used to help the fibers remain oriented in the longitudinal direction. For example, a deflector guide plate or other mechanical elements can be used, such as described in U.S. Patent Nos. 5,366,793 and 7,172,398. The direction of the air flow used to thin the fibers when forming the fibers can also be used to adjust to achieve longitudinal orientation, such as described in U.S. Patent No. 6,524,521. In addition to the above process, other known techniques can also be used to form the fibers. In one aspect, for example, the fibers can be quenched after their formation and then directly deposited on the formed wire without first drafting in the above manner. In such aspects, as described above, the flow rate of this airflow can be kept relatively low to enhance the orientation of the fibers in the MD direction to maintain orientation, however, it should be understood that in one aspect, the fibers are not mainly oriented in the MD direction.

[0065] See again Figure 2Once the fibers 23 are formed, they can be heated by a diffuser 33, which blows hot air onto the surface of the fibers to gently bond them together for further processing. A hot air knife can also be used as an alternative to the diffuser. Other techniques for consolidating the web, such as heated calendar rolls, can also be used. In any case, the resulting fibers can then be bonded to form a consolidated, coherent nonwoven web structure, for example to produce the elastomeric facing of the present disclosure. Any suitable bonding technique can generally be used in the present disclosure, such as adhesives or autogenous bonding (e.g., fusion and / or self-bonding of the fibers without the application of an external adhesive). Autogenous bonding can be achieved, for example, by contacting the fibers when they are in a semi-molten or tacky state, or simply by blending a tackifying resin and / or solvent with the polymer composition used to form the fibers. Suitable autogenous bonding techniques may include ultrasonic bonding, thermal bonding, air-through bonding, and the like. Hot spot bonding, for example, typically uses a nip formed between two rolls, at least one of which is patterned. On the other hand, ultrasonic bonding typically uses a gap formed between an ultrasonic horn and a patterned roll. Although the use of bicomponent fibers is described in detail above, extensible or elastomeric monocomponent fibers may also be used to produce fibers for nonwoven web materials (eg, facings).

[0066] The spunbond web may also be subjected to one or more additional post-processing steps. For example, the spunbond web may be stretched in the transverse direction using known techniques such as tenter frame stretching, groove roll stretching, etc. The spunbond web may also be subjected to other known processing steps such as perforation, heat treatment, etc.

[0067] Strength building layers

[0068] As described above, the nonwoven material manufactured according to the present disclosure includes at least one softness enhancing layer as described above and at least one strength building layer. The strength building layer can be directly attached to the softness enhancing layer, or can be separated from the softness enhancing layer by other layers.

[0069] The strength construction layer can be formed by continuous filaments or fibers, and can also include spunbond nonwoven webs. Fiber can be formed by non-elastic polymers such as polyolefins. Suitable polyolefins include, but are not limited to, homopolymers, copolymers and terpolymers of ethylene (for example, low density polyethylene, high density polyethylene, linear low density polyethylene, etc.), propylene (for example, syndiotactic, atactic, isotactic, etc.), butene, etc. In addition, blends and combinations of the above-mentioned materials are also suitable for use in combination with the present invention. For example, in one embodiment, the polymer part of polymer composition will include a polyolefin polymer greater than about 65% by weight, and in certain embodiments, polymer can include at least about 65,70,75,80,85,90,95% by weight olefin polymer and / or be less than about 100,99,98 or 97% by weight olefin polymer. In addition, in a specific embodiment, the polymer part of polymer composition can be composed of olefin polymers completely, for example, composed of polymers selected from the group of propylene, ethylene and butene polymers completely. The polymer composition will have a melt flow rate (MFR) of less than about 60 dg / minute, and in certain embodiments, will have an MFR greater than about 5, 8, 10, 12 or 15 dg / minute and / or less than about 55, 53, 50, 48 or 45 dg / minute. In addition, as known in the art, the polymer composition may optionally include one or more fillers, colorants (e.g., TiO2, pigments), antioxidants, softeners, surfactants, slip agents, etc. In particular, as known in the art, one or more slip agents (such as fatty acid amides) may be added to the polymer composition for melt spinning.

[0070] In one aspect, the strength building layer is formed from relatively small sized non-elastomeric fibers. For example, the fibers may have a denier of less than about 2, such as less than about 1.5. See Figure 3 , for example, shows one embodiment of a method and system 110 for producing a strength building layer.

[0071] In one embodiment, a polymer composition (not shown), typically in pellet form, 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 to a spinning pack 120 via a conduit 116. Although suitable ranges will vary with the specific polymer, in general, in order to limit degradation or other undesirable effects on the polymer, the molten polymer is typically not heated to a temperature of about 150°C, 125°C, 100°C, or 85°C above the melting point. In certain embodiments, the polymer may be heated to a temperature of about 30°C to about 150°C or about 45°C to about 125°C above its melting point.

[0072] Rotating assembly 120 may include various parts.For example, spinning assembly 120 may include a distributor, a filter or a screen, a support plate and a spinneret positioned in the flow direction in spinning assembly 120.For example, by directing the molten polymer stream laterally and downwardly to the spinneret, the molten polymer stream fed to the distributor may be spread to a wider region by the molten polymer stream.Screen or filter are used to filter impurities or other unwanted debris from the molten stream to prevent scaling of the spinneret.Suitable screen, for example, may include one or more stacked screens with a scope of approximately 50 to approximately 350 meshes.

[0073] In one aspect, the spinneret includes a conduit pattern extending through the spinneret thickness, wherein the molten polymer flows through the inlet opening, and flows through the relevant inlet channel or countersunk hole therefrom. The molten polymer then enters the capillary and is discharged through the orifice. For example, each capillary can have the same diameter as the outlet hole. In one embodiment, the conduit part (for example upstream) above the capillary can have a much larger diameter than the diameter of the capillary. For example, the diameter of the conduit part above the capillary can be at least about 250% larger than the capillary diameter, such as at least about 350%, such as at least about 450%.

[0074] The size of the outlet hole and the capillary can vary, for example, with a diameter of about 0.2mm to about 0.45mm. In certain embodiments, the outlet hole and / or the capillary can have a diameter of at least 0.2mm, 0.23mm, 0.25mm, 0.28mm or 0.29mm and / or be less than a diameter of about 0.45mm, 0.42mm and 0.40mm, 0.39mm or 0.38mm. As used herein, the diameter of the non-circular orifice is determined by the longest diameter line of the opening. The length (L) of the capillary extends in proportion to the diameter (D) of the outlet hole, and the length of the capillary divided by the outlet hole diameter (L / D) will be at least about 4. In certain embodiments, L / D can 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 L / D can 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 can be about 4 to about 10, about 5 to about 10, about 6 to about 10, about 5 to about 9, about 6 to about 9, or even about 6 to about 8.

[0075] The pattern of conduit, capillary and orifice in spinneret can change according to specific application.For example, spinneret can comprise a series of parallel extended rows.In certain embodiments, compared with adjacent CD edge, near the region of quenching airflow, the inside or central area of ​​extrusion zone can have the outlet hole of smaller interval.In this regard, the pattern of outlet hole can have CD extension section at or near the center of extrusion zone, and this extrusion zone has the conduit density of reduction or does not have outlet hole completely.For example, central area can have the part with the MD width of about 10 to about 60mm extending across CD center line, and this part does not have any conduit or has the capillary density (for example, capillary density is less than 70%, 60%, 50%, 40% or 30% of mean value) of remarkable reduction.

[0076] The spinneret may have a relatively high density or closely spaced outlet holes, for example, with 100 holes per cm. 2 Those having an outlet hole or hole density of at least about 3 outlet holes, the density being measured relative to the number of outlet holes in the extrusion area. In certain embodiments, the spinneret may have an outlet hole or hole density of at least about 3 outlet holes, the density being measured relative to the number of outlet holes in the extrusion area. 2 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 outlet holes and / or per cm 2 The outlet hole density of greater 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 outlet holes. On the other hand, the number of outlet holes in the spinneret will be greater than 5000 per meter of extrusion zone length (CD length), and in certain embodiments, will be greater than about 6000 / M, 6500 / M, 7000 / M, 7500 / M, 8000 / M or even 8500 / M per meter of extrusion zone length (CD length).

[0077] The molten polymer is pumped into and passes through spinning assembly and spinneret under high pressure, to reach throughput and exit velocity discussed below.The molten polymer is extruded from the exit orifice with a speed of at least about 0.3g / hole / minute or " g / h / m ".In order to calculate g / h / m, the quality of the extrudate composition pumped through the spinneret in a selected time period is divided by the quantity and the selected time of the exit orifice.In certain embodiments, extrusion rate can be at least about 0.3g / h / m, 0.33g / h / m, 0.35g / h / m, 0.37g / h / m, 0.4g / h / m, 0.43g / h / m or 0.45g / h / m and / or be no more than about 0.6g / h / m, 0.57g / h / m, 0.55g / h / m, 0.53g / h / m or 0.5g / h / m. In another aspect, the molten extrudate is pumped through and out of a spinneret having an exit velocity greater than about 10 ft / min 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 ft / min and / or may be no greater than about 45, 43, 40, 38, 35, 33, 30, 28, 25, or 23 ft / min. The exit velocity (V) of the extrudate at the exit orifice is preferably about 10 ft / min. e ) is calculated according to the following formula:

[0078]

[0079] M f = Mass flow rate of extrudate (lb. / min.)

[0080] E = number of outlet holes

[0081] ρ = density of the melt extrudate (lb. / ft 3 )

[0082] A = cumulative cross-sectional area of ​​the outlet openings (ft 2 )

[0083] On the other hand, the temperature of the polymer can be regionally controlled when it enters the spinning assembly or when it moves through the spinning assembly, so that relative to the molten polymer extrudate leaving the outlet opening inside the spinneret and the extrusion zone, the temperature of the molten polymer extrudate leaving the outlet opening near the quenching air is a higher temperature. With reference to the embodiments described herein, the molten polymer at a first temperature will be extruded from the outlet hole row near the CD edge, and the molten polymer at a second temperature (lower than the first temperature) will be extruded from the outlet hole row near the spinneret and the center of the spinning zone. In this regard, the quenching air will first impact and pass through the outside of the fiber bundle, and when it does so and cools the molten filaments, the quenching air will warm up before the inside or center-located filaments in the impact fiber bundle. When the filaments extruded outside are in a slightly elevated temperature relative to the filaments extruded inside, this will help to improve the processing under conditions described herein and produce more uniform frost lines on the whole tow.

[0084] When the molten polymer composition is extruded from the orifice of spinneret, a bunch of molten filaments that advance downwards and leave the spinneret are formed. Below the spinneret lower surface is blower 140 and 141, and they are introduced in the fiber bundle with cooling or quenching air 142 and 143, so that the molten filaments 130 are solidified at least in part.

[0085] Various quench air systems are known in the art and can be used in conjunction with the present invention.Quench air can be provided by a single blower at a single temperature, or can be provided by multiple blowers at different temperatures.For example, the quench system can include a stack of multiple quench air blowers on one or both sides of the fiber bundle, wherein the temperature of the air provided by the upper air box is different from the temperature of the air provided by the quench air box located below it.The quench air temperature will vary according to the characteristics of the polymer being melt-spun, the extrusion temperature, the quench air speed, the filament speed, the filament density and other factors known in the art.Generally speaking, quench air is provided at a temperature of about 5-60°C or about 5-35°C.In addition, quench air can be provided at a speed of about 30-120M / min.Usually, quench air is introduced into the tow at an angle perpendicular to or substantially perpendicular to the direction of flow of the filaments.However, the quench air can alternatively be directed into the molten filaments at an angle slightly acute or obtuse (i.e., slightly upward or downward) relative to the direction of flow of the filaments.

[0086] like Figure 3As can be seen in the figure, the quenched, solidified or substantially solidified filaments 132 are then fed into the filament drawing unit 150, which is used to further attenuate or reduce 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-speed air pneumatically draws the filaments 132 downward to leave the spinneret 124 and toward the forming wire 160. The quenched filaments 132 initially enter the contracted inlet opening 151 and are guided through the upper narrow channel 153. The contraction opening is typically a contraction opening with an MD width of no more than about 25% of the MD width of the extrusion zone. In certain embodiments, the contraction opening can have an MD width of no more than about 20%, 18%, 15%, 12% or 10% of the MD width of the extrusion zone, and / or an MD width of no less than about 0.5%, 1%, 2% or 3% of the MD width of the extrusion zone. The CD width of the contraction opening can be about the same as the CD length of the extrusion zone, and in certain embodiments can have a CD length that is at least about 1%, 2%, 4%, or 5% longer than the CD length of the extrusion zone. The quenched filaments and quenching air will enter the contraction opening together.

[0087] Additional high-speed air or drafting air can also be directed into the fiber drafting unit, such as being directed into the upper narrow passage 153 via a conduit and blower in fluid communication therewith. In addition, the drafting air introduced into the passage of the drafting unit can be introduced at a speed greater than about 50 M / sec or 75 M / sec. The drafting air can be directed into the passage from one or more sides of the drafting unit and at one or more positions vertically in the drafting unit. The angle of introduction can be perpendicular to the direction of filament flow, or a downward angle.

[0088] The fiber drafting unit may have additional channels below the initial contraction opening and associated channels. The additional channels below the initial contraction opening and associated channels may in turn be smaller, wider, or have sections of different MD widths than the contraction opening. Figure 3In the illustrated embodiment, the lower channel 155 is wider than the narrow upper channel 153 associated with the contraction opening 151. The filaments are drawn through the second lower channel 155 and then exit the drawing unit 150 through the outlet opening 157. In the illustrated embodiment, the velocity of the air rushing downward through the drawing unit draws the fibers downward away from the spinneret and toward the forming surface. This downward force on the continuous filaments applies a corresponding drawing force or pulling force that is transmitted along the quenched filaments and the extruded molten filaments. In a closed system, the pressure differential is also the primary driving force for drawing the air and filaments. In order to fully draw the fibers, a sufficient drawing distance is required. In this regard, the distance between the bottom surface of the spinneret to the convergence point of the fiber bundle at the contraction channel opening above the drawing portion is at least about 90 cm, and in certain embodiments, can be from about 90 cm to about 300 cm, or even from about 100 to about 230 cm. About Figure 3 In the illustrated embodiment, the drawing distance extends from the bottom surface 190 of the spinneret 124 to the inlet opening 151 of the narrow passage 153 at the top of the fiber drawing unit 150.

[0089] The pneumatic forces acting on the filaments are configured 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 determined by adjusting the terminal velocity (V T ) divided by the outlet velocity (V E ) is calculated as follows:

[0090]

[0091] The terminal velocity is calculated as follows:

[0092]

[0093] in:

[0094] V E = Initial velocity as discussed above

[0095] A E = Cross-sectional area of ​​the diameter of the outlet hole

[0096] A T = Cross-sectional area of ​​the resulting filament

[0097] As described, the entrained air forming aerodynamic force on the long filament enters the system from the opening or gap between the various components and various blowers located above the drafting unit. However, the long filament drafting unit generally adopts additional blowers or other air supply devices known in the art. The wall 154 of the drafting unit 150 can be optionally operated inwardly or outwardly to change the channel size at different positions in the drafting unit. In certain embodiments, the wall 154 can be moved inwardly or outwardly in discrete parts to form a channel with different sizes or widths, thereby regulating the diffusion of the long filaments in the drafting force and the fiber bundle. In addition, in order to improve the uniform diffusion and coverage of the formed nonwoven fabric, as known in the art, a deflector plate 156 can be used to diffuse the long filaments. Optionally, an electrostatic charging rod (not shown) or other components can be further used to help the diffusion, net forming and laying of the long filaments. Although the accompanying drawings describe an open air melt spinning system, it is easy to understand that the method of the present invention will also be used with a closed air system known in the art. Examples of various quenching and drawing systems suitable for use with the present invention include, but are not limited to, 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, U.S. Pat. No. 7,037,097 to Wilkie et al., U.S. 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 to Nitschke et al.

[0098] The fully drawn filaments 134 leave the bottom of the filament drawing unit 150 through the outlet opening 157 and are deposited on a forming surface 160, such as a fabric or wire. As known in the art, one or more vacuum devices 162 are positioned below the forming surface 160 to draw the filaments onto the forming surface 160 and form a relatively loose mat (matt) or net 136 of the filaments 134. The vacuum device also removes the suction air to prevent the deflected air from interfering with the laying of the filaments and / or interfering with the mat 136 once laid on the wire. Suctioning air from below the drawing unit can also help drive both air and fiber to move through the drawing unit and onto the forming wire.

[0099] Optionally, the felt of the filaments can be treated to give the required integrity of a certain minimum degree of additional treatment. This treatment can for example include reinforcing the felt with a compacting roller (not shown) or by using a high-speed through-air bonder 164. This through-air bonder only gives the minimum inter-filament bonding that is enough to carry out additional treatment and processing, without significantly melting the filaments. This bonder and method are described in the United States Patent No. 5,707,468 to Arnold et al. In addition, in order to obtain a fabric with a relatively high basis weight, multiple rows of spinnerets and drafting units can be sequentially positioned on a porous forming surface upstream of a consolidation and / or bonding device.

[0100] After formation, nonwoven felt is bonded ideally to increase its overall integrity and strength. In one aspect, felt can be mechanically bonded, such as by entanglement. In this regard, long filaments can be entangled by spunlace, and the spunlace includes subjecting the felt to one or more rows of fine high-pressure water jets, so that the long filaments are fully entangled with each other, thereby forming a coherent nonwoven fabric. In other embodiments, the felt can be bonded by one or more techniques known in the art (such as by applying adhesive, pressure, heat and / or ultrasonic energy). In some aspects, as known in the art, a pair of bonding rollers 166, 168 can be used to pattern bond the felt, wherein at least one of the rollers has a projection or "pin" pattern corresponding to the desired pattern of the bonding point of the nonwoven fabric 138 to be given to the felt and formed to be bonded. Two mating rollers form a roller gap, and the felt is passed through the roller gap by applying pressure and optional heat. Although suitable bonding elements can be formed without applying heat, heat is preferably used with pressure. As known in the art, bonding can be performed using a nip formed by a patterned roller and a smooth anvil roller ("pin-to-flat") or by two mating patterned rollers ("pin-to-pin"). With regard to the use of a smooth anvil roller, the roller can be a steel roller, or alternatively can be coated with an elastomeric material. By way of example only, various pattern bonding methods are shown and described in U.S. Patent No. 3,855,046 to Hansen et al., U.S. Patent No. 4,333,979 to Sciaraffa et al., U.S. Patent No. 4,374,888 to Bornslaeger, U.S. Patent No. 5,110,403 to Ehlert, U.S. Patent No. 5,858,515 to Stokes et al., U.S. Patent No. 6,165,298 to Samida et al., etc. As known in the art, pressure, temperature, dwell time, substrate composition, basis weight and other parameters will affect the selection of the desired degree of pressure and / or heat applied to the substrate to form bonding points. Alternatively, the mat of filaments may be bonded together by spraying, gravure rolling, or other means known in the art of applying adhesive in a desired pattern.

[0101] The resulting nonwoven fabric ideally has high tensile strength, uniform opacity (coverage), and / or a pleasing hand. For many applications, the bonded nonwoven fabric may have a weight of less than about 175 g / m 2 In certain embodiments, the nonwoven fabric may have a basis weight of less than about 150 g / m 2 , 120g / m 2 , 90g / m 2 , 60g / m 2 , 45g / m 2 , 35g / m 2 , 30g / m 2 , 25g / m 2 , 20g / m 2 , 18g / m 2 , 16g / m 2 , 14g / m 2 , 12g / m 2 , 10g / m 2 , 9g / m 2 , 8g / m 2 , 7g / m 2 and further, in certain embodiments, may have a basis weight of greater than about 4 g / m 2 , 5g / m 2 , 7g / m 2 or 10g / m 2 The basis weight of the nonwoven fabric can be 200 μm or less. In addition, the long filament formed by the method and provided in the corresponding nonwoven fabric can have an average denier (g / 9000M) less than about 1.5 or less, and can have 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 in certain embodiments. Similarly, the long filament formed by the method and provided in the corresponding nonwoven fabric can have an average fiber size less than or equal to about 16 microns, and can have an average fiber size 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 microns in certain embodiments.

[0102] Multi-layer nonwoven

[0103] According to the present disclosure, at least one strength building layer is combined with at least one softness enhancing layer to produce a multi-purpose nonwoven material. Generally speaking, the strength building layer forms the outer top surface of the nonwoven material. On the other hand, the strength building layer can form the bottom layer or middle layer of the material. The strength building layer and the softness enhancing layer can be as follows. Figure 2 and Figure 3 The two layers are then formed together into a multi-layer nonwoven web. The two layers can be attached together using any suitable bonding method, including thermal bonding, adhesive bonding, ultrasonic bonding, etc.

[0104] Alternatively, if Figure 4 As shown, Figure 4 The double row melt spinning system and method shown can be used to produce nonwoven materials. Figure 4 As shown, for example, the method for producing a nonwoven material includes a system 110 for producing a strength building layer and a system 21 for producing a softness enhancing layer. The system includes spunbond extruders 110 and 21 that produce fibers 50, which are then deposited onto a forming wire 52. If desired, a vacuum can be utilized to hold the fibers on the forming wire 52. The spunbond fibers 50 produce a softness enhancing layer on top of the strength building layer to produce a web 54. The web 54 can be optionally compressed by a compacting roller 56. As shown, a multilayer nonwoven material 30 is produced and then wound into a roll 62.

[0105] exist Figure 4 In the illustrated embodiment, two layers of nonwoven material 30 have been produced. However, it should be appreciated that, in order to produce nonwoven material having more than two layers, other extruders can be placed on the production line. Additional layers can be other strength construction layers, other softness reinforcing layers or other layers that may be needed. For example, nonwoven material can comprise approximately 2 to approximately 10 strength construction layers (comprising the increment of all strength construction layers therebetween), and nonwoven material can comprise approximately 2 to approximately 10 softness reinforcing layers (comprising the increment of all softness reinforcing layers therebetween). In one aspect, nonwoven material comprises approximately 3 to approximately 8 layers, comprises 1,2,3,4,5 or 6 strength construction layers and remaining softness reinforcing layers. In another aspect, nonwoven material comprises 4 layers, comprises 1,2 or 3 strength construction layers and remaining softness reinforcing layers.

[0106] Nonwoven materials made according to the present disclosure can be used in a variety of different applications. For example, nonwoven materials can be used in absorbent articles. "Absorbent article" refers to any article that can absorb water or other fluids. Some examples of absorbent articles include, but are not limited to, personal care absorbent articles, such as diapers, training pants, absorbent underpants, incontinence products, feminine hygiene products, swimsuits, baby wipes, etc.; medical absorbent articles, such as clothing, fenestration materials, pads, mattresses, bandages, absorbent sheets, and medical wipes; food surface tissues; clothing products, etc.

[0107] The nonwoven material 30 manufactured according to the disclosure can generally have a basis weight of about 5gsm to about 300gsm, including all 1gsm increments therebetween. In one embodiment, the basis weight can be about 5gsm to about 170gsm. Particularly advantageously, very lightweight materials can be produced according to the disclosure, with significant intensity and excellent softness. For example, less than about 30gsm, such as less than about 25gsm, such as less than about 20gsm, such as less than about 18gsm basis weight, and generally greater than about 7gsm, such as greater than about 9gsm, such as greater than about 11gsm, such as greater than about 13gsm basis weight, can obtain the above characteristics.

[0108] The weight ratio between the strength building layer and the softness enhancing layer may also vary depending on the specific application. In one embodiment, the softness enhancing layer may have a greater basis weight than the strength building layer. Alternatively, the strength building layer may have a higher basis weight than the softness enhancing layer. In one embodiment, the weight ratio between the strength building layer and the softness enhancing layer is from about 1:5 to about 5:1, such as from about 1:4 to about 4:1, such as from about 1:3 to about 3:1, such as from about 1:2 to about 2:1, such as from about 1:3 to about 1.5:1, such as from about 1:2 to about 1.1:1.

[0109] Elastic laminate

[0110] In one embodiment, the nonwoven material of the present disclosure can be incorporated into an elastic laminate. For example, the nonwoven material can be attached to an elastic backing. The elastic backing can be a film, or can include a plurality of parallel filaments, such as ribbons.

[0111] In some embodiments, the elastic film (e.g., film) is formed by one or more melt-processable (i.e., thermoplastic) elastomeric polymers. Any of a variety of thermoplastic elastomeric polymers can be used generally, including, for example, elastomeric polyesters, elastomeric polyurethanes, elastomeric polyamides, elastomeric copolymers, elastomeric polyolefins, etc. In some embodiments involving opening holes on the film, elastomeric semi-crystalline polyolefins are used because of their unique combination of mechanical and elastomeric properties. That is, the mechanical properties of such semi-crystalline polyolefins allow the formation of films that are easily opened during thermal bonding but still maintain their elasticity.

[0112] Semi-crystalline polyolefin has or can show a substantially regular structure. For example, semi-crystalline polyolefin can be substantially amorphous in its undeformed state, but forms crystal domains when stretched. The crystallinity of olefin polymers can be from about 3% to about 30%, from about 5% to about 25% in some embodiments, and from about 5% to about 15% in some embodiments. Similarly, semi-crystalline polyolefin can have a melting latent heat (ΔHf) of from about 15 to about 75 joules / gram ("J / g"), from about 20 to about 65J / g in some embodiments, and from 25 to about 50J / g in some embodiments, which is another indicator of crystallinity. Semi-crystalline polyolefin can also have a Vicat softening temperature of from about 10°C to about 100°C, from about 20°C to about 80°C in some embodiments, and from about 30°C to about 60°C in some embodiments. Semi-crystalline polyolefin can have a melting temperature of from about 20°C to about 120°C, from about 35°C to about 90°C in some embodiments, and from about 40°C to about 80°C in some embodiments. Latent heat of fusion (ΔHf) and melting temperature can be measured using differential scanning calorimetry ("DSC") according to ASTM D-3417, as is well known to those skilled in the art. Vicat softening temperature can be measured according to ASTM D-1525.

[0113] Exemplary semicrystalline polyolefins include polyethylene, polypropylene, blends thereof, and copolymers. In a specific embodiment, polyethylene as a copolymer of ethylene and α-olefins (such as C3-C20 α-olefins or C3-C12 α-olefins) is used. Suitable α-olefins can be linear or branched (e.g., one or more C1-C3 alkyl branches, or aryl groups). 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; 1-decene substituted with ethyl, methyl or dimethyl; 1-dodecene and styrene. Particularly desirable alpha-olefin comonomers are 1-butene, 1-hexene and 1-octene. The ethylene content of such copolymers can be from about 60 mol % to about 99 mol %, from about 80 mol % to about 98.5 mol % in some embodiments and from about 87 mol % to about 97.5 mol % in some embodiments. The content of alpha-olefins can also be in the range of from about 1 mol % to about 40 mol %, from about 1.5 mol % to about 15 mol % in some embodiments and from about 2.5 mol % to about 13 mol % in some embodiments.

[0114] The density of polyethylene can vary depending on the type of polymer used, but is generally in the range of 0.85 to 0.96 grams per cubic centimeter ("g / cm3"). A polyethylene "plastomer," for example, can have a density in the range of 0.85 to 0.91 g / cm3. Likewise, a "linear low density polyethylene" ("LLDPE") can have a density in the range of 0.91 to 0.940 g / cm3; a "low density polyethylene" ("LDPE") can have a density in the range of 0.910 to 0.940 g / cm3; and a "high density polyethylene" ("HDPE") can have a density in the range of 0.940 to 0.960 g / cm3. Density can be measured according to ASTM 1505.

[0115] Example 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 short chain branches that can be attributed to the incorporation of comonomers. "Long chain branches" 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 is as long as the polymer backbone to which it is attached. Preferred substantially linear polymers are substituted with 0.01 long chain branches per 1000 carbons to 1 long chain branch per 1000 carbons, and in some embodiments are substituted with 0.05 long chain branches per 1000 carbons to 1 long chain branch per 1000 carbons. In contrast to the term "substantially linear", the term "linear" means that the polymer lacks measurable or obvious long chain branches. That is, the polymer is substituted with less than 0.01 long chain branches per 1000 carbons on average.

[0116] Exemplary plastomers useful for forming films include those marketed under the designation EXACT TM Ethylene-based copolymer plastomers are available from ExxonMobil Chemical Company of Houston, Tex. Other suitable polyethylene plastomers are available under the name ENGAGE TM and AFFINITY TM Available from Dow Chemical Company, Michigan. Still other suitable ethylene polymers are available under the designation DOWLEX TM (LLDPE) and ATTANE TM(ULDPE) is available from The Dow Chemical Company. Other suitable ethylene polymers are described in U.S. Pat. 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., which are incorporated herein by reference in their entirety for all purposes.

[0117] Other polymers, such as propylene polymers may also be suitable for use as semi-crystalline polyolefins. Suitable plastomer propylene polymers may include, for example, propylene copolymers or terpolymers, including copolymers of propylene and alpha-olefins (e.g., C3-C20) such as ethylene, 1-butene, 2-butene, various pentene isomers, 1-hexene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 4-methyl-1-pentene, 4-methyl-1-hexene, 5-methyl-1-hexene, vinylcyclohexene, styrene, etc. The comonomer content of propylene polymers may be about 35 wt % or less, in some embodiments about 1 wt % to about 20 wt % and in some embodiments about 2 wt % to about 10 wt %. Preferably, the density of polypropylene (e.g., propylene / alpha-olefin copolymers) may be 0.91 grams per cubic centimeter (g / cm3) or less, in some embodiments 0.85 to 0.88 g / cm3 and in some embodiments 0.85 g / cm3 to 0.87 g / cm3. Suitable propylene polymers may be referred to as VISTAMAXX TM from ExxonMobil Chemical Co. of Houston, Tex.; under the name FINA TM (e.g., 8573) from Atofina Chemicals, Feluy, Belgium; TAFMER TM From Mitsui Petrochemical Industries and VERSIFY TM Commercially available from Dow Chemical Co. of Midland, Mich. Other examples of suitable propylene polymers are described in U.S. Pat. Nos. 6,500,563 to Datta et al., 5,539,056 to Yang et al., and 5,596,052 to Resconi et al., which are incorporated herein by reference in their entirety for all purposes.

[0118] Any of a variety of known techniques can be used to form semi-crystalline polyolefins generally. For example, olefin polymers can be formed using free radicals or coordination catalysts (for example, Ziegler-Natta). Preferably, olefin polymers are formed by single-site coordination catalysts such as metallocene catalysts. Such catalyst systems produce such ethylene copolymers, wherein comonomers are randomly distributed in the molecular chain and uniformly distributed in the parts of different molecular weights. Metallocene-catalyzed polyolefins are for example described in U.S. Patent No. 5,571,619 to McAlpin et al., U.S. Patent No. 5,322,728 to Davis et al., U.S. Patent No. 5,472,775 to Obijeski et al., U.S. Patent No. 5,272,236 to Lai et al. and U.S. Patent No. 6,090,325 to Wheat et al., which are incorporated herein by reference in their entirety for all purposes. The example of metallocene catalyst comprises 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, cyclopentadienyl titanium trichloride, ferrocene, hafnium dichloride, isopropyl(cyclopentadienyl-1-fluorenyl)zirconium dichloride, molybdenum dichloride, nickelocene, silverocene dichloride, ruthenocene, titanocene dichloride, hydrogen chlorozirconocene, zirconocene dichloride etc.The polymer made with metallocene catalyst has narrow molecular weight range usually.For example, the polymer of metallocene catalysis can have polydispersity value (Mw / Mn) below 4, controlled short chain branching distribution and controlled isotacticity.

[0119] The melt flow index (MI) of the semicrystalline polyolefin can generally vary, but is typically in the range of about 0.1 g / 10 min to about 100 g / 10 min, in some embodiments from about 0.5 g / 10 min to about 30 g / 10 min, and in some embodiments from about 1 to about 10 g / 10 min, these values ​​being measured at 190° C. The melt flow index is the weight (in grams) of polymer that can be forced through an orifice (0.0825 inch diameter) of an extrusion rheometer when subjected to a force of 5000 grams at 190° C. for 10 minutes, and can be determined according to ASTM test method D1238-E.

[0120] Of course, other thermoplastic polymers can also be used to form elastic films alone or in combination with semi-crystalline polyolefins. For example, a substantially amorphous block copolymer can be used, the copolymer having at least two monoalkenyl aromatic polymer blocks separated by at least one saturated conjugated diene polymer block. The monoalkenyl aromatic blocks can include styrene and its analogs and homologues, such as o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, p-methylstyrene, etc., and other monoalkenyl polycyclic aromatic compounds, such as vinyl naphthalene, vinyl anthracene, etc. Preferred monovinyl aromatics 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 dienes with another monomer, wherein the blocks are mainly conjugated diene units. Preferably, the conjugated diene contains from 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 the like.

[0121] Exemplary thermoplastic elastomer copolymers are available under the trade name Available from Kraton Polymers LLC, Houston, Tex. The polymers include styrene-diene block copolymers such as styrene-butadiene, styrene-isoprene, styrene-butadiene-styrene and styrene-isoprene-styrene. The 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-(ethylene-butylene), styrene-(ethylene-propylene)-styrene-(ethylene-propylene), and styrene-ethylene-(ethylene-propylene)-styrene. These block copolymers may be linear, radial or star-shaped molecular configurations. Specific Block copolymers include those sold under the trade names G 1652, G 1657, G 1730, MD6673, and MD6973. Various suitable styrene 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 those sold under the trade names S-EP-S elastomeric copolymer available from Kuraray Company, Ltd. of Okayama, Japan. Still other suitable copolymers include those available under the trade name SIS and SBS elastomeric copolymers available from Dexco Polymers of Houston, Tex. Another suitable polymer is composed of an ABAB tetrablock copolymer, such as discussed 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) ("S-EP-S-EP") block copolymer.

[0122] The amount of one or more elastomeric polymers used in the film can vary, but is generally about 30% by weight or more of the film, about 50% by weight or more in some embodiments and about 80% by weight or more of the film in some embodiments. In one embodiment, for example, one or more semi-crystalline polyolefins account for about 70% by weight or more of the film, about 80% by weight or more of the film in some embodiments and about 90% by weight or more of the film in some embodiments. In other embodiments, a blend of one or more semi-crystalline polyolefins and one or more elastomeric block copolymers can be used. In such embodiments, one or more block copolymers can account for about 5% by weight to about 50% by weight of the blend, about 10% by weight to about 40% by weight in some embodiments and about 15% by weight to about 35% by weight in some embodiments. Similarly, one or more semi-crystalline polyolefins can account for about 50% by weight to about 95% by weight of the blend, about 60% by weight to about 90% by weight in some embodiments and about 65% by weight to about 85% by weight in some embodiments. Of course, it should be understood that other elastomers and / or non-elastomeric polymers can also be used in the film.

[0123] In addition to polymers, the elastic film may also include other components as known in the art. For example, in one embodiment, the elastic film includes fillers. Fillers are microparticles or other forms of materials that can be added to the film polymer extrusion blend and do not chemically interfere with the film, but can be evenly dispersed throughout the film. Fillers can serve multiple purposes, including enhancing the opacity and / or breathability of the film (i.e., vapor permeable and substantially liquid impermeable). For example, the filled film can be breathable by stretching, which causes the polymer to separate from the filler and form microporous channels. Breathable microporous elastic films are described, for example, in U.S. Patents Nos. 5,997,981, 6,015,764, and 6,111,163 to McCormack et al.; U.S. Patent No. 5,932,497 to Morman et al.; U.S. Patent No. 6,461,457 to Taylor et al., which are incorporated herein by reference in their entirety for all purposes.

[0124] Filler can have spherical or non-spherical shape, and its mean particle size is in the scope of about 0.1 to about 7 microns.The example of suitable filler includes but is not limited to calcium carbonate, various clays, silicon dioxide, aluminum oxide, barium carbonate, sodium carbonate, magnesium carbonate, talcum, barium sulfate, magnesium sulfate, aluminum sulfate, titanium dioxide, zeolite, cellulose type powder, kaolin, mica, carbon, calcium oxide, magnesium oxide, aluminum hydroxide, pulp powder, wood powder, cellulose derivative, chitin and chitin derivative.Suitable coating (such as stearic acid) also can be applied to filler particles when needed.When utilizing, filler content can change, such as about 25 % by weight to about 75 % by weight of film, about 30 % by weight to about 70 % by weight in some embodiments and about 40 % by weight to about 60 % by weight in some embodiments.

[0125] Other additives may also be incorporated into the film, such as melt stabilizers, processing stabilizers, heat stabilizers, light stabilizers, antioxidants, heat aging stabilizers, brighteners, anti-blocking agents, binders, tackifiers, viscosity modifiers, etc. Examples of suitable tackifier resins may include, for example, hydrogenated hydrocarbon resins. REGALREZ TM Hydrocarbon resins are examples of such hydrogenated hydrocarbon resins and are available from Eastman Chemical. Other tackifiers may be found under the name ESCOREZ TM Available from ExxonMobil. Viscosity modifiers such as polyethylene waxes (e.g., EPOLENE from Eastman Chemical) may also be used. TMC-10). Phosphite stabilizers (e.g., IRGAFOS available from Ciba Specialty Chemicals, Terrytown, NY and DOVERPHOS available from Dover Chemical Corp., Dover, Ohio) are exemplary melt stabilizers. In addition, hindered amine stabilizers (e.g., CHIMASSORB available from Ciba Specialty Chemicals) are exemplary heat and light stabilizers. In addition, hindered phenols are commonly used as antioxidants in film manufacturing. Some suitable hindered phenols include those available under the trade names Such as The invention relates to the invention of the present invention to a film which is a kind of film-forming agent. The film may be a film-forming agent comprising a plurality of adhesives, such as tackifiers, antioxidants, stabilizers, etc., and ...

[0126] The elastic film can be monolayer or multilayer. The multilayer film can be prepared by coextrusion, extrusion coating or by any conventional layering process of the layer. Such a multilayer film generally includes at least one base layer and at least one epidermis layer, but can include any number of desired layers. For example, the multilayer film can be formed by a base layer and one or more epidermis layers, wherein the base layer is formed by a semi-crystalline polyolefin. In such embodiments, the epidermis layer can be formed by any film-forming polymer. If necessary, the epidermis layer can include a softener, a polymer or a polymer blend of a relatively low melting point that makes the layer more suitable as a heat-sealing adhesive layer for thermally bonding the film to a nonwoven web. For example, the epidermis layer can be formed by an olefin polymer or its blend, as described above. Other film-forming polymers suitable for use alone or in combination with other polymers include ethylene-vinyl acetate, ethylene-ethyl acrylate, ethylene-acrylic acid, ethylene-methyl acrylate, ethylene-n-butyl acrylate, nylon, ethylene-vinyl alcohol, polystyrene, polyurethane, etc.

[0127] The thickness of one or more epidermis layers is usually selected to not substantially impair the elastic properties of the film. For this reason, each epidermis layer can individually account for about 0.5% to about 15% of the total thickness of the film, and in some embodiments, account for about 1% to about 10% of the total thickness of the film. For example, each epidermis layer can have a thickness of about 0.1 to about 10 microns, about 0.5 to about 5 microns in some embodiments, and about 1 to about 2.5 microns in some embodiments. Similarly, the base layer can have a thickness of about 1 to about 40 microns, about 2 to about 25 microns in some embodiments, and about 5 to about 20 microns in some embodiments.

[0128] The characteristic of the resulting film can be varied as required usually. For example, before stretching, the film usually has a basis weight of about 100 g / m2 or lower and about 50 to about 75 g / m2 in some embodiments. After stretching, the film usually has a basis weight of about 60 g / m2 or lower and about 15 to about 35 g / m2 in some embodiments. The film after stretching also can have a total thickness of about 1 to about 100 microns, about 10 to about 80 microns in some embodiments and about 20 to about 60 microns in some embodiments.

[0129] Although the backing is described above as being thin, it will be appreciated that the backing may also be in the form of parallel elastic filaments, including ribbons.

[0130] Lamination

[0131] In some embodiments, laminating the nonwoven material to the film includes, for example, thermal bonding, adhesive bonding, ultrasonic bonding, pressure bonding, needle punching, or some combination thereof.

[0132] In some embodiments, in order to simultaneously form holes and bond between the film and the nonwoven web material, lamination is generally achieved by patterned bonding techniques (e.g., thermal point bonding, ultrasonic bonding, etc.), in which the material is supplied to a nip defined by at least one patterned roller. Examples of such simultaneous apertures and bonding are described in U.S. Patent No. 7,803,244 to Siqueira et al., the entire contents of which are incorporated herein by reference for all purposes. Thermal point bonding, for example, generally employs a nip formed between two rollers, at least one of which is patterned. On the other hand, ultrasonic bonding generally employs a gap formed between an ultrasonic horn and a patterned roller.

[0133] More specifically, the patterned roller for example comprises a plurality of raised bonding elements, so that film is bonded to the nonwoven web material and forms holes in the film simultaneously. The size of bonding elements can be specially customized to be conducive to forming holes in the film and strengthening the bonding between the film and the nonwoven material. For example, bonding elements are usually selected to have a relatively large length dimension. The length dimension of bonding elements can be from about 300 to about 5000 microns, from about 500 to about 4000 microns and from about 1000 to about 2000 microns in some embodiments. The width dimension of bonding elements can be equally from about 20 to about 500 microns, from about 40 to about 200 microns and from about 50 to about 150 microns in some embodiments. In addition, " element aspect ratio " (ratio of the length of element to its width) can be from about 2 to about 100, from about 4 to about 50 in some embodiments and from about 5 to about 20 in some embodiments.

[0134] In addition to the size of the bonding element, the overall bonding pattern can also be selectively controlled to achieve the desired hole formation. For example, in one embodiment, such a bonding pattern is selected: wherein the longitudinal axis (the longest dimension along the center line of the element) of one or more of the bonding elements is skewed relative to the longitudinal direction (" MD ") of the elastic film. For example, one or more of the bonding elements can be oriented with respect to the longitudinal direction of the elastic film at about 30 ° to about 150 °, about 45 ° to about 135 ° in some embodiments, and about 60 ° to about 120 ° in some embodiments. Like this, the bonding element will present a relatively large surface to the film along the direction substantially perpendicular to the direction in which the film moves. This increase gives the film the area where the shear force is located, and thus helps the formation of the hole.

[0135] The pattern of bonding elements is typically selected so that the nonwoven composite has a total bond area of ​​less than about 50% (as determined by conventional optical microscopy).In some embodiments, the film is tensioned and then laminated to the nonwoven web with a total bond area of ​​between 5% and 30%.

[0136] In some embodiments, the bonding density is also generally greater than about 50 bonds / square inch and in some embodiments from about 75 to about 500 pin bonds / square inch. A suitable bonding pattern for this new elastomer laminate is referred to as "S-shaped weaving" pattern, and is described in U.S. Patent No. 5,964,742 to McCormack et al., which is incorporated herein by reference in its entirety for all purposes. The S-shaped weaving pattern generally has a bonding element density of from about 50 to about 500 bonding elements per square inch and from about 75 to about 150 bonding elements per square inch in some embodiments. Another suitable bonding pattern is referred to as "rib knitting" pattern and is described in U.S. Patent No. 5,620,779 to Levy et al., which is incorporated herein by reference in its entirety for all purposes. The rib knitting pattern generally has a bonding element density of from about 150 to about 400 bonding elements per square inch and from about 200 to about 300 bonding elements per square inch in some embodiments. Another suitable pattern is a "wire braid" pattern having a bonding element density of from about 200 to about 500 bonding elements per square inch and in some embodiments from about 250 to about 350 bonding elements per square inch. Other bonding patterns that can be used are described in U.S. Pat. No. 3,855,046 to Hansen et al., U.S. Pat. No. 5,962,112 to Haynes et al., U.S. Pat. No. 6,093,665 to Sayovitz et al., U.S. Pat. No. D375,844 to Edwards et al., U.S. Pat. No. D428,267 to Romano et al., and U.S. Pat. No. D390,708 to Brown, which are incorporated herein by reference in their entirety for all purposes.

[0137] In order to realize such simultaneous hole formation and bonding, without significantly softening the polymer of nonwoven web material, selectively control bonding temperature and pressure. For example, one or more rollers may be heated to about 50°C to about 160°C, in some embodiments, about 60°C to about 140°C, and in some embodiments, about 70°C to about 120°C surface temperature. Similarly, the pressure ("nip pressure") applied by the roller during thermal bonding can be in the range of about 75 to about 600 pounds per linear inch, about 100 to about 400 pounds per linear inch in some embodiments, and about 120 to about 200 pounds per linear inch in some embodiments. Of course, the residence time of the material can affect the specific bonding parameters adopted.

[0138] As described, another factor that affects the formation of holes and lamination simultaneously is the tension of the film during bonding. The increase of film tension is for example usually associated with the increase of hole size. Of course, too high film tension can adversely affect the integrity of the film. Therefore, in some embodiments, a stretch ratio of about 1.5 or larger, or 2 to 6, or 2.5 to 7.0, or 3.0 to 5.5 is used to realize the tension force of the desired degree 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 be roughly the same as the draft ratio, which can be determined by the linear speed (for example, the speed of the nip roller) of the film during lamination divided by the linear speed (for example, the speed of the casting roller or the blow molding nip roller) formed by the film.

[0139] The film can be "pre-stretched" (before lamination) using rollers rotating at different rotational speeds so that the sheet is stretched to a desired stretch ratio in the machine direction. For example, the film can be stretched to a ratio of 2 to 6 in the longitudinal direction, that is, 2 to 6 times the unstretched length of the film. The uniaxially stretched film can also be oriented in the transverse machine direction to form a "biaxially stretched" film. The orientation temperature distribution during the "pre-stretching" operation is usually lower than the melting point of one or more polymers in the film, but high enough to make the composition most easily drawn or stretched. For example, the film can be stretched at a temperature of about 15°C to about 50°C, about 25°C to about 40°C in some embodiments, and about 30°C to about 40°C in some embodiments. When "pre-stretched" in the above manner, the degree of stretching during lamination may be maintained, or increased or slightly reduced (retracted) to the desired degree of tension.

[0140] In other embodiments, the lamination method does not involve opening holes in the film, but rather involves bonding the film to a nonwoven web material (e.g., an extensible or elastomeric facestock). Lamination without intentional hole formation can be achieved, for example, by thermal bonding, adhesive bonding, ultrasonic bonding, and / or pressure bonding.

[0141] Figure 5 An exemplary process for forming a composite material from an elastic film and a nonwoven web material is shown. The raw materials (e.g., elastomeric polymer) of the film backing can be dry mixed together (i.e., without solvent) and then added to a hopper (not shown) of an extrusion device 40. The raw materials can alternatively be blended with a solvent. In the hopper, the materials are dispersedly mixed in the melt and compounded, such as batch and / or continuous compounding techniques using, for example, a Banbury mixer, a Farrel continuous mixer, a single screw extruder, a twin screw extruder, etc.

[0142] The composite material (not shown) supplied to the extrusion device 40 is then blown into the nip roller 42 to form a single-layer precursor elastic film 10. The roller 42 may be maintained at a temperature sufficient to solidify and quench the precursor elastic film 10 as it is formed, for example, typically about 20° C. to 60° C. The resulting precursor elastic film is typically non-porous, but it may of course have small cuts or tears due to processing.

[0143] The film 10 may be stretched and thinned in the machine direction by passing through a film orientation unit or machine direction orientator ("MDO") 44, such as commercially available from Marshall and Willams, Co. of Providence, RI. The MDO has a plurality of stretching rolls 46 that gradually stretch and thin the film 10 in the machine direction. Although Figure 5 Four pairs of rollers 46 are shown, but it should be understood that the number of rollers can be greater or less, depending on the desired level of stretching and the degree of stretching between the various rollers. The film 10 can also be stretched in other directions. For example, the film 10 can be clamped at its lateral edges by chain clamps and conveyed to a tenter oven. In the tenter oven, the film 10 can be drafted to a desired stretch ratio in the transverse direction by chain clamps that separate in forward travel.

[0144] According to the present disclosure, at least one side of the elastic backing 10 is laminated to the nonwoven material according to the present disclosure. Figure 5 In the illustrated embodiment, the film 10 is laminated to a first nonwoven material on one side and to a second nonwoven material on the opposite side. Each nonwoven material can be made in-line or can be unwound from a supply roll. Figure 5 In the illustrated embodiment, 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 placed adjacent to the film 10 and bonded to the film.

[0145] In some embodiments, the nonwoven web material is laminated to the elastic film 10 using thermal bonding techniques, although other processes such as adhesive bonding, ultrasonic bonding, pressure bonding, and / or needle punching may be used. Figure 5 In the embodiment of the present invention, for example, materials 30 and 30a are directed to a nip defined between rollers 58 to be laminated to the elastic film 10. One or both of the rollers 58 may include a plurality of raised bonding elements and / or may be heated. During lamination, the elastic film 10 is melt-bonded to the nonwoven web materials 30 and 30a at a plurality of discrete bonding sites. That is, the one or more elastomeric polymers of the elastic film 10 soften and / or melt, whereby they can physically trap the fibers of the nonwoven web materials 30 and 30a. The elastic film 10 may have a certain viscosity so that it also adheres to the fibers during lamination. For example, Figure 6The resulting laminate 32 is shown in , which is a block diagram representation of an elastomeric laminate.

[0146] The resulting laminate 32 can then be wound and stored on a take-up roll 60. Optionally, the laminate 32 is maintained under tension, such as by using a line speed of the roll 60 that is the same as the speed of the one or more stretching rolls 46. However, the composite material 32 can be allowed to retract slightly before being wound onto the take-up roll 60. This can be accomplished by using a slower line speed of the take-up roll 60.

[0147] In some embodiments, because the elastic film 10 is tensioned prior to lamination, after the tension is removed, it will retract toward its original longitudinal length and shorten in the longitudinal direction, thereby wrinkling or forming folds in the laminate 32. Thus, the resulting elastic laminate 32 becomes extensible in the longitudinal direction to the extent that wrinkles or folds in the laminate 32 can be pulled back flat and then further stretched as described above by virtue of the extensible properties of the nonwoven web 30, thereby allowing the elastic film 10 to elongate, even beyond its tensioned length in the longitudinal direction. In addition, the extensible laminate 32 (e.g., the nonwoven web 30 bonded to the film 10) can be extensible or elastomeric in the transverse direction because the extensible nonwoven web 30 (and the film 10) allows for such biaxial stretching (i.e., stretching in both the longitudinal and transverse directions).

[0148] In some embodiments, the laminate 32 can be mechanically stretched in the transverse and / or longitudinal directions to enhance extensibility. In one embodiment, the laminate 32 can pass through two or more rollers having grooves in the CD and / or MD directions. Such grooved companion / anvil roller devices 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 can pass through two or more rollers having grooves in the CD and / or MD directions. The grooved rollers can be constructed of steel or other hard materials (such as hard rubber).

[0149] In addition to the grooved rollers described above, other techniques may also be used to mechanically stretch the laminate 32 in one or more directions. For example, the laminate 32 may be passed through a tenter that stretches the laminate 32. Such tenters are well known in the art and are described, for example, in U.S. Patent Application Publication No. 2004 / 0121687 to Morman et al. The laminate 32 may also be necked. Suitable necking techniques are described in U.S. Patent Nos. 5,336,545, 5,226,992, 4,981,747, and 4,965,122 to Morman, and U.S. Patent Application Publication No. 2004 / 0121687 to Morman et al., which are incorporated herein by reference in their entirety for all purposes.

[0150] The laminate 32 described above can be used in a variety of applications. As described above, for example, the laminate 32 can be used in absorbent articles.

[0151] The elastic laminates made according to the present disclosure can have an excellent balance of properties, namely, a combination of excellent softness and high strength properties. For example, the elastic laminates can exhibit a strength of greater than about 1800 g. f , such as greater than about 1900 g f , such as greater than about 2000g f , such as greater than about 2200g f , such as greater than about 2400g f , such as greater than about 2600g f , such as greater than about 2800g f , such as greater than about 3000g f , and usually less than about 5000g f The average burst strength.

[0152] The laminate may also exhibit a stretch to stop value of greater than about 170%, such as greater than about 175%, and typically less than about 225% at 2000g in the machine direction. In the cross direction, the laminate may exhibit a stretch to stop value of about 25% to about 70%, such as about 45% to about 70%, at 2000g. The laminate may have a stretch to stop value of greater than about 320g at 50% elongation in the machine direction. f , such as greater than about 350g f , such as greater than about 370g f , and usually less than about 420g f , such as less than about 400g f In the transverse direction, the average load at 50% elongation can be greater than about 1500g f , such as greater than about 1600g f , such as greater than about 1700 g f , such as greater than about 1800gf , and usually less than about 2200g f .

[0153] 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 typically less than about 6%, such as less than about 5.9%. The average peak load energy of the elastic laminate may typically 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 typically less than about 7000 gf cm.

[0154] The elastic laminate can also have excellent air permeability. For example, the laminate can show 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 typically less than about 200 cfm.

[0155] With respect to hand, the laminate may exhibit 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 typically greater than about 10.

[0156] Single-sided or double-sided elastic laminates made according to the present disclosure can achieve all of the above-mentioned physical properties, and the laminates can have a basis weight of less than about 40gsm, such as less than about 35gsm, such as less than about 30gsm, such as less than about 25gsm, such as less than about 23gsm, such as less than about 20gsm, such as less than about 18gsm, such as less than about 16gsm, such as less than about 14gsm, and greater than about 12gsm.

[0157] In one embodiment, the present disclosure relates to a nonwoven material comprising a strength building 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 have a softness enhancing layer comprising spunbond fibers randomly arranged to form a web; the softness enhancing layer may include a top layer of the nonwoven material, wherein the spunbond fibers contained in the softness enhancing layer include elastomeric fibers.

[0158] In one embodiment, the nonwoven material comprises two or more strength building layers. In one embodiment, the nonwoven material comprises two or more softness enhancing layers. In one embodiment, the nonwoven material comprises two or more softness enhancing layers and two or more strength building layers.

[0159] In any of the above embodiments, the strength building layer may be present relative to the softness enhancing layer 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.

[0160] In one embodiment, any embodiment of the above-mentioned nonwoven material can be incorporated into an elastomeric laminate. In one embodiment, the laminate includes an elastic backing attached to the nonwoven material. In one embodiment, the backing includes 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, the first nonwoven material is attached to the first surface of the elastic film, and the second nonwoven material is attached to the second surface of the elastic film. In one embodiment, the strength building layer of the nonwoven material can be attached to the elastic film, and the softness enhancing layer can form the outer surface of the laminate.

[0161] The present disclosure may be better understood by reference to the following examples.

[0162] Testing Procedure

[0163] Air permeability test

[0164] The air permeability test measures the rate at which air flows through a known dry sample area. The air permeability of each sample was measured using a Textest FX3300 air permeability tester available from Schmid Corporation (having offices in Spartanburg, SC).

[0165] Samples from each test sample were cut and placed so that the sample extended beyond the clamping area of ​​the air permeability tester. Test samples were obtained from sample areas that were free of folds, crease lines, perforations, wrinkles, and / or any deformations that would make them different from the rest of the test material.

[0166] Tests were conducted under standard laboratory conditions of 23 ± 1 °C (73.4 ± 1.8 °F) and 50 + 2% humidity. The instrument was turned on and allowed to warm up for at least 5 minutes before any sample was tested. The instrument was calibrated according to the manufacturer's guidelines before analyzing the test material. The pressure sensor of the instrument was reset to zero by pressing the NULL RESET button on the instrument. Before testing, if required between samples or between samples, the dust filter screen was cleaned according to the manufacturer's instructions. The following specifications were selected for data collection: (a) Unit of measurement: cubic feet per minute (cfm); (b) Test pressure: 125 Pascals (0.5 inches or 12.7 mm of water column); and (c) Test head: 38 square centimeters (cm.sup.2). Because test results obtained with test heads of different sizes are not always similar, test heads of the same size should be used to test samples to be compared.

[0167] Press the NULL RESET button before each test series or when the red light on the instrument display comes on. Before pressing the NULLRESET button, the test head is open (no sample in place) and the vacuum pump is at a complete stop.

[0168] Each sample is placed on the lower test head of the instrument. Start the test by manually pressing the clamping lever until the vacuum pump starts automatically. Use the RANGE knob to stabilize the Range indicator in the green or yellow area. After the digital display stabilizes, the air permeability of the sample is displayed and the value is recorded. Repeat the test procedure for 10 samples of each sample and record the average value of each sample as the air permeability.

[0169] Bursting strength test

[0170] The burst strength test uses a constant rate of extension (CRE) tensile tester to measure the amount of force required to rupture (ie, break) the test sample. The burst strength of each sample was measured using an MTS Criterion Model 42 tensile tester commercially available from MTS Systems Corporation.

[0171] A 4 inch x 4 inch (101.6 mm x 101.6 mm) test specimen was cut from each test sample and placed in a fixture with a circular opening defining a test area. A puncture assembly with a smooth, spherical probe tip was arranged perpendicular to the circular test area and centered below the circular area. The puncture assembly included a spherical probe attached to the end of a socket, which was fixed to a tensile tester by a locking nut. A burst strength test was performed according to TAPPI T570 pm-00 using a test speed of 6 inches per minute and a 50 Newton load cell. The puncture assembly was raised at the specified test speed so that the spherical probe tip contacted and eventually penetrated the test sample to the sample breaking point. The maximum force applied by the puncture assembly at the moment of sample rupture was recorded as the burst strength (gram-force (gf)). The average value of 10 samples for each test sample was recorded.

[0172] Stretch to Stop Test

[0173] "Stretching end" refers to the difference between the unstretched dimension of the stretchable laminate and the maximum stretched dimension of the stretchable laminate when a specific tension is applied, and the ratio determined by dividing the difference by the unstretched dimension of the stretchable laminate. If the stretch to stop value is expressed as a percentage, the 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) when 2000 grams of force is applied has a 100% stretch to stop value (at 2000 grams). The stretch to stop value may also be referred to as "maximum non-destructive elongation". Unless otherwise stated, the stretch to stop value reported herein is under a load of 2000 grams. In the elongation or stretch to stop value test, a 3-inch × 7-inch (7.62 cm × 17.78 cm) sample (the larger size is longitudinal, transverse, or any direction between the two) is placed in the jaws of the Sintech machine, with a gap of 5 cm between the jaws. The sample is then pulled to a stop load of 2000 grams at a crosshead speed of about 20 inches / minute (50.8 cm / minute). For the stretchable laminate of the present invention, it is desirable that it exhibits a stretch stop value of about 30%-400%, alternatively about 50%-300%, or about 80%-250%. The stretch stop test is conducted in the extensibility (stretch) direction. The above procedure can also be used to test the average load at 50% elongation.

[0174] Drape coefficient test

[0175] The Cusick drape test may be performed using any suitable drape tester to obtain the drape coefficient. Commercially available drape testers include the TF118 tester labeled by Testex of Dongguam, China or the Model 665 drape tester sold by James H Heal & Co. of Halifax, England. The drape test may be performed according to ISO test 9073-9 (2008).

[0176] TS7 and TS750 Testing

[0177] The 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 a test piece that applies a defined contact pressure. The contact between the vertical blades and the test piece generates vibrations that are sensed by a vibration sensor. The sensor then transmits the signal to a personal computer (PC) for processing and display. The signal is displayed as a frequency spectrum. To measure the TS7 and TS750 values, the blade is pressed against the sample with a load of 100 mN and the blade rotates at a speed of 2 revolutions per second.

[0178] To measure the TS7 and TS750 values, two different frequency analyses were performed. The first frequency analysis was performed in the range of approximately 200 Hz to 1000 Hz, and the peak amplitude occurring at 750 Hz was recorded as the TS750 value. The TS750 value represents the surface smoothness of the sample. High amplitude peaks are associated with rougher surfaces. The second frequency analysis was performed in the range of 1 to 10 kHz, and the peak amplitude occurring at 7 kHz was recorded as the TS7 value. The TS7 value represents the softness of the sample. Lower amplitudes are associated with softer samples. The units of TS750 and TS7 values ​​are both dB V 2 rms.

[0179] Strain and Load

[0180] The tensile properties of nonwoven materials were determined essentially according to ASTM Standard D-5034.

[0181] Specifically, a nonwoven web sample having a size of 25 mm (width) × 127 mm (length) is cut or otherwise provided. A constant speed extension type tensile tester is used. The tensile test system is a Sintech tensile tester, which can be purchased from Sintech Corp. of Cary, NC. The tensile tester is equipped with TESTWORKS 4.08B software from MTS Corporation to support the test. The appropriate load cell is selected so that the test value falls within the range of 10% to 90% of the full scale load. The sample is held between a clamp having a front and back surface of 25.4 mm × 76 mm. The clamp face is rubberized, and the longer dimension of the clamp is perpendicular to the pulling direction. The clamp pressure is pneumatically maintained at a pressure of 40 pounds per square inch. The tensile test is carried out at a rate of 300 mm per minute, with a gauge length of 10.16 cm and a break sensitivity of 40%.

[0182] Five samples were tested. The strain was measured at a force of 2,000 g, and the load at 50% was measured in the longitudinal and transverse directions. The results of the five samples were averaged.

[0183] Martindale Wear

[0184] This test measures the relative wear resistance of a sample in accordance with Worldwide Strategic Partners ("WSP") Standard Test No. 20.5 (08). A circular test piece having a diameter of 165 mm ± 6.4 mm and an area of ​​18,258 square millimeters is subjected to the desired number of cycles (10 or 60) with an abrasive at a pressure of 9 kilopascals (kPa). The abrasive is a 36 inch x 4 inch x 0.05 thick silicone rubber wheel reinforced with glass fiber having a rubber surface hardness of 81A durometer hardness (81 ± 9 Shore A hardness). The test piece is inspected for the presence of surface fuzz (bulking of fibers), pilling (small piles of fibers), streaks, peeling, or holes, and is assigned a numerical rating of 1, 2, 3, 4, or 5 based on comparison with a set of similarly numbered standard photographs, where "1" indicates the greatest wear resistance and "5" indicates the worst. The test is conducted using a Martindale Wear and Abrasion Tester, such as Model 103 or 403 available from James H. Heal & Company, Ltd. of West Yorkshire, United Kingdom.

[0185] Thermal conductivity and heat dissipation

[0186] The thermal dissipation of samples is measured using a C-Therm TCi thermal conductivity analyzer according to ASTM D7984-16 ("Test Method for Thermal Dissipation of Fabrics Using a Modified Transient Plane Source (MTPS) Apparatus"). The default C-Therm TCi thermal conductivity analyzer uses the Modified Transient Plane Source (MTPS) technique to characterize the thermal conductivity and dissipation of materials. It uses a single-sided interface thermoreflectance sensor that applies an instantaneous constant heat source to the sample.

[0187] Example 1

[0188] Various elastic laminates are made according to the present disclosure wherein an elastic backing is attached to a facing layer on each side of a backing consisting of a strength building layer and a softness enhancing layer.The strength building layer is attached to a film backing.

[0189] Samples made according to the present disclosure were compared to a similar laminate containing elastomeric spunbond fibers as facing layers only on each side and an elastomeric laminate containing low denier polypropylene spunbond fibers as facing layers on each side.

[0190] More specifically, the following samples were produced. In each sample, the elastic backing was a film. The film comprised about 28% to about 37% of the basis weight of the laminate.

[0191] Sample No. 1: Each face layer includes a strength building layer and a softness enhancing layer. The strength building layer is attached to the film and includes a 4 gsm spunbond web made of polypropylene fibers having a denier of about 1. The softness enhancing layer is a 6 gsm spunbond web made of bicomponent fibers that include an elastomeric core surrounded by a polyethylene sheath. The core includes two elastomeric polymers (VERSIFY polymer and VISTAMAXX polymer), metallocene-catalyzed polypropylene, and a secondary amide. The laminate is point bonded in a bonding pattern that occupies about 15% to about 17% of the surface area.

[0192] Sample No. 2: Same structure as sample No. 1

[0193] Sample No. 3: Same structure as Sample No. 1, except the strength building layer had a basis weight of 5 gsm and the softness enhancing layer had a basis weight of 8.5 gsm.

[0194] Sample No. 4: The facing layer attached to the elastic backing consisted only of the softness-enhancing layer described in Sample No. 1. The facing layer on each side of the film had a basis weight of 17 gsm.

[0195] Sample No. 5: The facing layer attached to the elastic backing consisted only of the strength building layer described in Sample No. 1. The facing layer on each side of the film had a basis weight of 10 gsm.

[0196] The above samples were tested for various physical properties and the following results were obtained.

[0197] Table 1

[0198]

[0199] Table 2

[0200]

[0201]

[0202] Table 3

[0203]

[0204] Table 4

[0205]

[0206] Table 5

[0207]

[0208] Example 2 A more resilient laminate was made in accordance with the present disclosure having substantially the same structure and made in the same manner as described in Example No. 1 above.

[0209] Samples No. 6-23 were produced. Each sample included an elastic backing attached to a facing layer on each side. Samples No. 8-22 were made according to the present disclosure, wherein each facing layer included a strength building layer and a softness enhancing layer. The strength building layer was attached to the film backing.

[0210] Samples No. 6 and 7 included a facing layer consisting solely of elastomeric spunbond fibers. Sample No. 23, on the other hand, included a facing layer consisting solely of low denier polypropylene spunbond fibers.

[0211] The elastomeric spunbond fibers and low denier polypropylene spunbond fibers had the same construction as described in Example 1. However, Samples No. 15 and 16 contained 5 wt. % of an elastomeric polymer (VISTAMAXX polymer) in the fibers of the strength building layer.

[0212] The elastic laminates were tested for various properties. Tables 6, 7 and 8 show the following results.

[0213] Table 6

[0214]

[0215] Table 7

[0216]

[0217]

[0218] Table 8

[0219]

[0220]

[0221] As shown in the above examples, laminates made according to the present disclosure exhibit an excellent combination of properties.

[0222] These and other modifications and variations of the present invention may be practiced by those of ordinary skill in the art without departing from the spirit and scope of the present invention as more particularly described in the appended claims. In addition, it should be understood that the aspects of the various embodiments may be interchangeable in whole or in part. In addition, it will be appreciated by those of ordinary skill in the art that the foregoing description is by way of example only and is not intended to limit the present invention as further described in such appended claims.

Claims

1. A nonwoven material comprising: a strength building layer comprising spunbond fibers randomly arranged to form a web, the spunbond fibers having a denier of less than about 2 and made from a non-elastomeric polymer; and A softness-enhancing layer comprising spunbond fibers randomly arranged to form a web, the softness-enhancing layer comprising a top layer of the nonwoven material, the spunbond fibers contained in the softness-enhancing layer comprising elastomeric fibers.

2. The nonwoven material of claim 1, wherein the nonwoven material comprises two or more strength building layers.

3. The nonwoven material of claim 1, wherein the nonwoven material comprises two or more softness-enhancing layers.

4. The nonwoven material of claim 1, wherein the nonwoven material comprises two or more softness-enhancing layers and two or more strength-building layers.

5. The nonwoven material of any one of the preceding claims, wherein the spunbond fibers contained in the strength building layer are made from a polypropylene polymer.

6. The nonwoven material of claim 5, wherein the polypropylene polymer comprises at least about 70 weight percent, such as at least about 80 weight percent, such as at least about 90 weight percent, of the spunbond fibers contained in the strength building layer.

7. The nonwoven material of any of the preceding claims, wherein the spunbond fibers contained in the strength building 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.

8. The nonwoven material of any of the preceding claims, wherein the spunbond fibers contained in the softness-enhancing layer comprise elastomeric bicomponent fibers comprising a core surrounded by a sheath.

9. The nonwoven material of claim 8, wherein the core of the bicomponent fiber comprises a polypropylene-based elastomer and a secondary amide.

10. The nonwoven material of claim 9, wherein the polypropylene-based elastomer comprises an ethylene copolymer, an α-olefin copolymer, or a combination thereof.

11. The nonwoven material of claim 9 or 10, wherein the sheath comprises a non-elastomeric polymer.

12. The nonwoven material of any one of claims 9 to 11, wherein the sheath comprises a polyethylene polymer.

13. The nonwoven material of any one of claims 9 to 11, wherein the secondary amide is a fatty acid amide.

14. The nonwoven material of any one of claims 9 to 13, wherein the secondary amide comprises a structure having one of the following: in, R 14 , R 15 , R 16 and R 18 Independently selected from C7-C 27 Alkyl groups and C7-C 27 an alkenyl group; and R 17 Selected from C8-C 28 Alkyl groups and C8-C 28 Alkenyl group.

15. The nonwoven material of any one of claims 9 to 14, wherein the core comprises a second elastomer.

16. The nonwoven material of any of the preceding claims, wherein the nonwoven material has a basis weight of about 5 gsm to about 170 gsm.

17. The nonwoven material of any one of claims 1 to 15, wherein the nonwoven material has a basis weight of about 9 gsm to about 30 gsm.

18. A nonwoven material as claimed in any of the preceding claims, wherein the strength building layer is present in a weight ratio relative to the softness enhancing layer 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.

19. An elastomeric laminate comprising the nonwoven material as claimed in any one of the preceding claims.

20. 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 wherein the strength building layer is attached to the first surface of the elastic film.

21. The elastomeric laminate of claim 19 or 20, wherein the nonwoven material has a basis weight of about 9 gsm to about 30 gsm, and wherein the elastomeric laminate has a basis weight of greater than about 1800 gsm. f , such as greater than about 2200g f , such as greater than about 2500g f , such as greater than about 2800g f , such as greater than about 3000g f The bursting strength.

22. The elastomeric laminate of claim 19, 20 or 21, wherein the elastomeric laminate has a tensile strength in the machine direction of greater than about 170 g at 2,000 g. f , such as greater than about 175g f , and less than about 225g f The average STS.

23. The elastomeric laminate of claim 20 wherein a second nonwoven material is attached to the second surface of the backing, and wherein the strength building layer of the second nonwoven material is directly attached to the second surface of the elastic film.

24. 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.

25. The elastomeric laminate of claims 19, 20, 21, 22, 23 or 24, wherein the elastomeric laminate exhibits 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 typically greater than about 10.

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