Spot bonded extrusion laminate

Abstract

Point bonded extrusion laminates (PELs) are provided. The PELs include at least a first nonwoven layer and an elastic film laminated together by a first plurality of discrete bond sites, thereby bonding the first nonwoven layer to a first side of the elastic film. The first plurality of discrete bond sites define a first bond area and a first bond pattern between the first nonwoven layer and the first side of the elastic film. The PELs also include a first unbonded portion of the first nonwoven layer located between the first plurality of discrete bond sites, wherein the first unbonded portion of the first nonwoven layer is not bonded to the first side of the elastic film.

Description

Technical Field

[0001] Embodiments of the present invention generally relate to point-bonded extrusion laminates (PELs) comprising at least a first nonwoven layer and an elastic membrane, both of which have been laminated together by a first plurality of discrete adhesive portions. The PEL also includes a first non-adhesive portion of the first nonwoven layer that extends out of the xy-plane of the PEL to impart a desired wrinkled outer surface to the PEL. Background Technology

[0002] Disposable absorbent products, such as diapers, are used to collect and store bodily fluids, such as urine and feces, from the wearer, such as an infant. To prevent undesirable leakage, absorbent products should fit the wearer well and be easy to fasten. For example, it may be desirable for certain portions of disposable absorbent products to provide a level of elasticity to offer comfort to multiple wearers and / or ease of fastening. Summary of the Invention

[0003] One or more embodiments of the present invention can solve one or more of the above-mentioned problems. According to certain embodiments of the present invention, a point-bonded extruded laminate (PEL) is provided, the PEL comprising at least a first nonwoven layer and an elastic film, the first nonwoven layer and the elastic film being laminated together by a first plurality of discrete adhesive portions, thereby bonding the first nonwoven layer to a first side of the elastic film. The first plurality of discrete adhesive portions define a first adhesive region and a first adhesive pattern between the first nonwoven layer and the first side of the elastic film. The PEL also includes a first non-adhesive portion of the first nonwoven layer located between the first plurality of discrete adhesive portions, wherein the first non-adhesive portion of the first nonwoven layer is not bonded to the first side of the elastic film.

[0004] In another aspect, the present invention provides a disposable absorbent article comprising at least one component containing a PEL, such as those disclosed herein. At least one component may include, for example, an elastic ear, panel, or waistband of a diaper.

[0005] On the other hand, the present invention provides a method for preparing a PEL, such as those described and disclosed herein. The method may include the following steps: (a) providing or forming a first nonwoven layer; (b) melt-extruding an elastic film onto the first nonwoven layer; (c) pressing an elastic film layer onto the first nonwoven layer to form an intermediate material by passing the elastic film and the first nonwoven layer through a roll gap including a dot-bonding pressure roller, wherein the dot-bonding pressure roller includes a first plurality of discrete protrusions forming a first plurality of discrete adhesive portions between the first nonwoven layer and a first side of the elastic film, and wherein the first plurality of discrete adhesive portions define a first adhesive region and a first adhesive pattern between the first nonwoven layer and the first side of the elastic film, and wherein a first non-adhesive portion of the first nonwoven layer located between the first plurality of discrete adhesive portions is not bonded to the first side of the elastic film; and (d) activating the intermediate material to form a PEL, wherein activating the intermediate material forms deformed portions projecting outward from the xy-plane. Attached Figure Description

[0006] The invention will now be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, embodiments of the invention. In fact, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to enable this disclosure to meet applicable legal requirements. Throughout the text, the same reference numerals denote the same elements, wherein: Figure 1 A PEL comprising a first nonwoven layer and an elastic membrane is shown according to certain embodiments of the present invention; Figure 2 A PEL comprising an elastic membrane disposed between a first nonwoven layer and a second nonwoven layer is shown according to certain embodiments of the present invention; Figure 3A Extruded laminates of the prior art are shown, having continuous or full adhesion (e.g., regional adhesion as opposed to point adhesion) formed by rollers with smooth or flat surfaces, wherein the extruded laminate has no non-adhesive areas.

[0007] Figure 3B A PEL according to certain embodiments of the invention is shown, wherein a non-bonded region of the nonwoven layer forms a deformable portion or region that extends out of the xy plane of the PEL according to certain embodiments of the invention to provide rogusity (e.g., variation in the height amplitude of the surface defined by the nonwoven layer). Figure 4 A nip roll according to certain embodiments of the present invention is shown, having a plurality of protrusions that can be used to form PEL; Figure 5This is a schematic diagram illustrating the effect of the activation step in forming PEL from intermediate materials according to certain embodiments of the present invention; Figure 6 The load versus strain diagrams of elastic ear flaps or sheets commercially used as disposable absorbent articles (e.g., diapers) and comparative laminates are shown. Figure 7 The load versus strain diagrams of PEL and contrast laminates commercially used as waistbands for disposable absorbent products (e.g., diapers) are shown. Figure 8 The diagram shows the tensile strength of PEL and the tensile strain of the laminated material used commercially as a belt for disposable absorbent products (e.g., diapers). Figure 9 The diagram shows load versus strain plots for PEL and contrasting laminates used commercially as waistbands in disposable absorbent products (e.g., diapers); and Figure 10 The diagram shows the tensile strength of PEL and the tensile strain of the laminated material, which is commercially used as a belt for disposable absorbent products (such as diapers). Detailed Implementation

[0008] The invention will now be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, embodiments of the invention. In fact, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to enable this disclosure to meet applicable legal requirements. As used in the specification and appended claims, the singular forms “a,” “an,” and “the” include plural references unless the context clearly indicates otherwise.

[0009] This invention generally relates to polymeric elastic materials (PELs) applicable to disposable absorbent articles such as baby and / or adult diapers and methods for preparing said PELs. For example, PELs can be used alone or in combination with other materials to form elastic waistbands, elastic sheets, and / or elastic ear flaps. The PELs utilize multiple discrete (e.g., separate and individual) bonding sites between one or more nonwoven layers and an elastic membrane. For example, these embodiments can increase the stretchability, softness, and / or wrinkleability of the outer surface of the PEL. In this regard, one or more nonwoven layers comprise multiple non-bonded portions, wherein the fibers of one or more nonwoven layers have been at least partially deformed, for example by an activation step, to provide the PEL with a wrinkled outer surface having multiple deformed portions extending outward from the xy-plane of the PEL. According to certain embodiments of the invention, the formation of the PEL can advantageously combine film extrusion and lamination in a single step. According to certain embodiments of the invention, the PEL may include multiple orifices extending through the PEL or no orifices extending through the PEL. Additionally or alternatively, the PEL may, for example, have no adhesive between the elastic membrane and the nonwoven layers.

[0010] The term “substantially” or “substantially” may cover the total amount specified in certain embodiments of the invention, or the total amount that is substantially but not specified in other embodiments of the invention (e.g., 95%, 96%, 97%, 98% or 99% of the specified total amount).

[0011] The term "polymer" or "polymerized," as used interchangeably herein, may include homopolymers, copolymers such as block, graft, random and alternating copolymers, terpolymers, etc., and their blends and modifications. Furthermore, unless specifically limited otherwise, the term "polymer" or "polymerized" shall include all possible structural isomers; stereoisomers, including but not limited to geometric isomers, optical isomers, or enantiomers; and / or any chiral molecular configuration of such polymer or polymeric material. These configurations include, but are not limited to, isotactic, syndiotactic, and atactic configurations of such polymer or polymeric material. The term "polymer" or "polymerized" shall also include polymers made from various catalyst systems, including but not limited to Ziegler-Natta catalyst systems and metallocene / single-center catalyst systems. According to certain embodiments of the invention, the term "polymer" or "polymerized" shall also include polymers produced by fermentation methods or of biological origin.

[0012] As used herein, the terms "nonwoven" and "nonwoven web" can include fiber webs having a single fiber, fiber, and / or filament structure, said fibers, fibers, and / or filaments interwoven in a repeating manner identifiable in knitted or woven fabrics. According to certain embodiments of the invention, nonwoven fabrics or webs can be formed by any method conventionally known in the art, such as meltblowing, spunbonding, needle punching, water entanglement, air-blown web formation, and bonded carding. As used herein, a "nonwoven web" can comprise multiple individual fibers that have not undergone a consolidation process. In some cases, a "nonwoven web" can comprise multiple layers, such as one or more spunbond layers and / or one or more meltblown layers. For example, a "nonwoven web" can comprise a spunbond-meltblown-spunbond structure.

[0013] As used herein, the terms “fabric” and “nonwoven fabric” can include fiber webs in which multiple fibers are mechanically entangled or interconnected, fused together and / or chemically bonded together. For example, a nonwoven fiber web of individually laid fibers can be bonded or consolidated to bond at least a portion of the individual fibers together to form a bonded (e.g., cohesive) fiber web of interconnected fibers.

[0014] As used herein, the term "layer" may include a generally identifiable combination of similar material types and / or functions present in the XY plane.

[0015] As used herein, the terms "consolidated" and "consolidated" can include bringing together at least a portion of the fibers of a nonwoven fiber web to bring them closer together or attach them therebetween (e.g., thermally fused together, chemically bonded together, and / or mechanically entangled together) to form one or more bonded sites that, compared to an unconsolidated fiber web, increase resistance to external forces (e.g., abrasion and tension). For example, one or more bonded sites can include discrete or localized regions of the fiber web material that have been softened or melted and optionally subsequently or simultaneously compressed to create discrete or localized deformations within the fiber web material. Furthermore, the term "consolidated" can include the entire nonwoven fiber web that has been processed such that at least a portion of the fibers are brought closer together or attached therebetween (e.g., thermally fused together, chemically bonded together, and / or mechanically entangled together), for example by thermal bonding or mechanical entanglement (e.g., water entanglement), as just a few examples. Additionally, the terms "consolidated" and "consolidated" can include adhesion performed by air-penetration bonding operations. As used herein, the terms "hot-air bonded" and "hot-air bonded" can include nonwoven fiber webs bonded by an bonding method, wherein hot air is used to fuse fibers at the surface of the fiber web and optionally within the fiber web. By way of example only, the hot air can be blown through the web in a conveyor-type oven or drawn through the web as it passes through a porous drum, creating a vacuum. The temperature and rate of the hot air are parameters that can determine the level or degree of bonding in the nonwoven fiber web. According to certain embodiments of the invention, the temperature of the hot air can be high enough to melt, induce flow, and / or fuse multiple fibers (e.g., amorphous fibers) having a lower melting point temperature or a lower melting point temperature starting point to multiple fibers (e.g., semi-crystalline or crystalline fibers) having a higher melting point temperature or a lower melting point temperature starting point. According to certain embodiments of the invention, such a fiber web can be considered a "bonded nonwoven," a "nonwoven fabric," or simply a "fabric."

[0016] As used in this article, “melt-spun” or “melt-spun” usually refers to spunbond or melt-blown fiber forming methods.

[0017] As used herein, the term "spunbond" can include fibers formed by extruding molten thermoplastic material as fibers from a plurality of fine, generally circular capillaries of a spinneret, followed by a rapid reduction in the diameter of the extruded fibers. According to embodiments of the invention, spunbond fibers are generally non-sticky when deposited onto a collection surface and can be substantially continuous as disclosed and described herein. It should be noted that the spunbond materials used in certain composites of the invention can include nonwovens described in the literature as SPINLACE®. Spunbond fibers, for example, comprise continuous fibers.

[0018] As used herein, the term "continuous fiber" refers to a fiber that is not cut from its original length before being formed into a nonwoven fiber web or nonwoven fabric. The average length of a continuous fiber can be greater than about 15 centimeters to greater than one meter, and can be up to the length of the resulting fiber web or fabric. For example, the continuous fiber used herein may include fibers in which the fiber length is at least 1,000 times greater than the average fiber diameter, such as at least about 5,000, 10,000, 50,000, or 100,000 times greater than the average fiber diameter.

[0019] As used herein, the terms "activated" or "activated" may include mechanically deformed material or methods of mechanical deformation, such as by incremental stretching, to increase the ductility of at least a portion of the material. In one embodiment, for example, a material (e.g., a nonwoven web or fabric) may be activated by, for example, incrementally stretching the material in at least one direction.

[0020] As used herein, the term "incremental stretching" can include a method in which a web or fabric is supported at closely spaced locations and then stretched unsupported segments of the web or fabric between these closely spaced locations. Non-limiting examples of incremental stretching rollers designed for longitudinal and transverse stretching can be found in U.S. Patent No. 4,223,059, the contents of which are incorporated herein by reference. According to one embodiment, incremental stretching can include a process performed by embossing the fabric, as shown in U.S. Patent Application 2014 / 0276517, the contents of which are incorporated herein by reference.

[0021] As used herein, the term "longitudinal" or "MD" refers to the direction in which the fabric is produced or conveyed. The term "transverse" or "CD" as used herein refers to the direction in which the fabric is substantially perpendicular to the MD.

[0022] As used interchangeably herein, the terms "elastic," "elastomeric," or "elastic" may include materials that, when stretched and released, recover to near their original length (e.g., within 20%, 10%, 5%, 3%, or 1% of their original length). The terms "elastic," "elastomeric," or "elastic" as used interchangeably herein may also include materials that exhibit the ability to be stretched and released several times and to repeatedly apply the same or only slightly lower forces when stretched at the same level of extension. Elastic materials may, for example, include elastomers, such as elastomeric polymers. According to certain embodiments, non-limiting exemplary elastomers may include one or more elastomers, such as acrylates; polyolefins, such as polyethylene, polypropylene, polybutene, polyhexene, and polyoctene; polystyrene; polyurethanes; polyesters, such as polyethylene terephthalate; polyamides, such as nylon; natural or synthetic rubber resins, such as styrene block copolymers (e.g., styrene-isoprene-styrene, styrene-butadiene-styrene, styrene-propylene-styrene copolymers, styrene-butene-styrene); epoxy resins; vinyl acetate, such as ethylene vinyl acetate; polydiorganosiloxane polyurea copolymers; copolymers thereof and mixtures thereof. Alternatively or concurrently, non-limiting elastomers may include elastomeric polyolefins (e.g., VISTAMAXX™ from ExxonMobil Chemical Company, VERSIFY™ from Dow Chemical Company, propylene-ethylene elastomers, and AFFINITY™), polyether block amide copolymers (e.g., PEBAX® from Arkema Group), polyester block amide copolymers, copolyester thermoplastic elastomers (e.g., ARNITEL® from DSM Engineering Plastics, HYTREL® from EIDuPont de Nemoursand Company), thermoplastic polyurethane elastomers, and / or combinations thereof. In some embodiments, exemplary elastomers may include VISTAMAXX™ propylene-based elastomers (commercially available from ExxonMobile), which comprise copolymers of propylene and ethylene. For example, VISTAMAXX™ propylene-based elastomers comprise isotactic polypropylene microcrystalline regions and random amorphous regions.

[0023] According to certain embodiments of the present invention, a point-bonded extruded laminate (PEL) is provided. The PEL includes at least a first nonwoven layer and an elastic film, the first nonwoven layer and the elastic film being laminated together by a first plurality of discrete adhesive portions, thereby bonding the first nonwoven layer to a first side of the elastic film. The first plurality of discrete adhesive portions define a first adhesive region and a first adhesive pattern between the first nonwoven layer and the first side of the elastic film. The PEL also includes a first unbonded portion of the first nonwoven layer located between the first plurality of discrete adhesive portions, wherein the first unbonded portion of the first nonwoven layer is not bonded to the first side of the elastic film. According to certain embodiments of the present invention, the PEL further includes a second nonwoven layer. For example, the elastic film is located between and adjacent to the first and second nonwoven layers. The PEL may also include a second plurality of discrete adhesive portions bonding the second nonwoven layer to a second side of the elastic film. The plurality of second discrete adhesive portions may define a second adhesive region and a second adhesive pattern between the second nonwoven layer and the second side of the elastic film. The PEL may also include a second non-adhesive portion of a second nonwoven layer located between a second plurality of discrete adhesive portions, wherein the second non-adhesive portion of the second nonwoven layer is not adhered to a second side of the elastic membrane.

[0024] According to certain embodiments of the invention, the first nonwoven layer, the second nonwoven layer, or both may comprise a variety of nonwoven fiber webs or nonwoven fabrics, such as spunbond nonwoven materials, carded nonwoven materials, meltblown nonwoven materials, spunlace nonwoven materials, or any combination thereof. Additionally or alternatively, the first nonwoven layer, the second nonwoven layer, or both comprise a basis weight of about 3 to about 50 gsm, for example at least about any one of the following: 3, 5, 9, 10, 12, and 15 gsm, and / or at most about any one of the following: 50, 45, 40, 35, 30, 25, 20, and 15 gsm.

[0025] According to certain embodiments of the invention, the first nonwoven layer, the second nonwoven layer, or both may comprise a polymer composition comprising a polymer component and optional additive components. The polymer component may, for example, comprise one or more polyolefins, such as polypropylene or copolymers thereof, or polyethylene or copolymers thereof. Additionally or optionally, the polymer component may comprise one or more polymers produced by fermentation or of biological origin. For example, the polymer component may comprise one or more polylactic acid (PLA), polyhydroxyalkanoate (PHA), poly(hydroxycarboxylic acid), or any combination thereof.

[0026] According to certain embodiments of the invention, at least a portion of the first non-adhesive portion, the second non-adhesive portion, or both includes a deformable portion projecting outward from the xy-plane. In this respect, the deformable portion may form a ring or mound extending outward from the xy-plane of the PEL to provide one or more outer surfaces with a visually identifiable folded structure. For example, the deformable portion may have an average height of about 1 to about 10 mm, such as at least about any of the following: 1, 2, 3, 4, and 5 mm, and / or at most about any of the following: 10, 9, 8, 7, 6, and 5 mm.

[0027] For example, Figure 1 A PEL 1 comprising a first nonwoven layer 10 and an elastic membrane 20, according to certain embodiments of the present invention, is shown. Figure 1 As shown, the first plurality of adhesive portions 12 bond the first nonwoven layer 10 to the elastic membrane 20, wherein at least a portion of the first non-adhesive portion includes a deformable portion 14 protruding outward from the xy plane of the PEL. Figure 2 PEL 1 is shown, which includes an elastic membrane 20 disposed between a first nonwoven layer 10 and a second nonwoven layer 30. (See diagram) Figure 2 As shown, a first plurality of adhesive portions 12 bond the first nonwoven layer 10 to the elastic membrane 20, wherein at least a portion of the first non-adhesive portion includes a deformable portion 14 protruding outward from the xy plane of the PEL, and a second plurality of adhesive portions 32 bond the second nonwoven layer 30 to the elastic membrane 20, wherein at least a portion of the second non-adhesive portion includes a deformable portion 34 protruding outward from the xy plane of the PEL.

[0028] As described above, PEL departs from the conventional use of extruded laminates having a continuous or total adhesive region (e.g., an adhesive area) between the nonwoven layer and the elastic film. In this respect, for example, the first adhesive area, the second adhesive area, or both comprise about 5% to about 40%, for example at least about any one of the following: 5, 6, 8, 10, 12, 15, 18, and 20%, and / or at most about any one of the following: 40, 38, 35, 32, 30, 28, 25, 22, and 20%. Alternatively or concurrently, the first plurality of discrete adhesive portions, the second plurality of discrete adhesive portions, or both may have an average adhesive area of ​​about 0.25 mm² to about 3 mm², for example, at most about any one of the following: 3, 2.5, 2.25, 2, 1.75, 1.5, 1.25, 1 and 0.75 mm² and / or at least about any one of the following: 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 1 and 1.25 mm².

[0029] Alternatively or alternatively, the first plurality of discrete adhesive portions, the second plurality of discrete adhesive portions, or both may be circular, polygonal, rhomboid, elliptical, or any combination thereof. For example, the first plurality of discrete adhesive portions, the second plurality of discrete adhesive portions, or both may include combinations of different adhesive sizes and / or different shapes. Alternatively or alternatively, the first adhesive pattern, the second adhesive pattern, or both include, for example, wavy patterns, misaligned rhomboid patterns, linear patterns, or any combination thereof.

[0030] Figure 3A Extruded laminates of the prior art are shown, having continuous or fully bonded (e.g., regional bonding as opposed to spot bonding) formed by rollers with smooth or flat surfaces, wherein the extruded laminate has no non-bonded areas. In such extruded laminates, the nonwoven layer does not include any non-bonded areas to provide free fibrous portions for deformation and forming a wrinkled surface. Instead, Figure 3B A PEL according to certain embodiments of the invention is shown, wherein a non-adhesive region of the nonwoven layer forms a deformable portion or region that, in some embodiments of the invention, extends the xy plane of the PEL to provide wrinkles (e.g., variations in the height amplitude of the surface defined by the nonwoven layer).

[0031] Figure 4 A dot-bonding pressure roller 50 according to certain embodiments of the invention is shown, having a plurality of protrusions 52, 56 extending from continuous non-rising portions 54, 58 that can be used to form PELs. Exemplary protrusions 52, 56 are shown only one pair of exemplary configurations or shapes of the protrusions.

[0032] According to certain embodiments of the invention, the elastic membrane may include an average thickness of about 10 to about 300 micrometers, for example, at least about any of the following: 10, 15, 20, 50, 80, 100, 120, and 150 micrometers, and / or at most about any of the following: 300, 250, 200, and 150 micrometers. Alternatively or additionally, the elastic membrane may comprise 1 to about 8 individual layers, for example, at least about any of the following: 1, 2, 3, and 4 layers, and / or at most about any of the following: 8, 7, 6, 5, and 4 layers. Alternatively or additionally, the elastic membrane may have a basis weight of about 10 to about 80 gsm, for example, at least about any of the following: 10, 15, 20, 25, 30, 35, and 40 gsm, and / or at most about any of the following: 80, 75, 70, 65, 60, 55, 50, 45, and 40 gsm.

[0033] According to certain embodiments of the present invention, the elastic film comprises one or more elastomers, such as acrylates; polyolefins, such as polyethylene, polypropylene, polybutene, polyhexene, polyoctene; polystyrene; polyurethane; polyesters, such as polyethylene terephthalate; polyamides, such as nylon; natural or synthetic rubber resins, such as styrene block copolymers (e.g., styrene-isoprene-styrene, styrene-butadiene-styrene, styrene-propylene-styrene copolymers, styrene-butene-styrene); epoxy resins; vinyl acetate, such as ethylene vinyl acetate; polydiorganosiloxane polyurea copolymers; copolymers thereof and mixtures thereof.

[0034] According to certain embodiments of the invention, the PEL may have a total basis weight of about 10 to about 200 gsm, for example at least about any of the following: 10, 12, 20, 30, 40, 50, 60, 70, 80, 90 and 100 gsm, and / or at most about any of the following: 200, 190, 180, 170, 160, 150, 140, 130, 120, 110 and 100 gsm.

[0035] According to certain embodiments of the invention, the PEL has no adhesive. Alternatively or additionally, the PEL may have a film coverage of at least about 80%, for example, at least about any of the following: 80, 85, and 90% and / or at most about any of the following: 100, 99, 98, 97, 96, 95, 94, 93, 92, 91, and 90%. Alternatively or additionally, the PEL may have an elongation at break of about 250 to about 500%, for example, at least about any of the following: 250, 280, 300, 320, and 350%, and / or at most about any of the following: 500, 480, 450, 420, 400, 380, and 350%. Alternatively, the PEL may have a breaking elongation (%) ratio to basis weight (gsm) from about 4 to about 10, for example at least about any of the following: 4, 4.2, 4.5, 4.8, 5, 5.2, 5.5, 5.8 and 6, and / or at most about any of the following: 10, 9.5, 9, 8.5, 8, 7.5, 7, 6.5 and 6.

[0036] According to certain embodiments of the invention, the PEL may include a plurality of holes extending through the PEL. The plurality of holes may define an open area of ​​the PEL in a relaxed state (e.g., unstretched) of about 3% to about 30%, for example at least about any of the following: 3, 5, 8, 10, 12, 15, 18 and 20%, and / or at most about any of the following: 30, 28, 25, 22 and 20%.

[0037] In another aspect, the present invention provides a disposable absorbent article comprising at least one component containing a PEL, such as those described and disclosed herein. At least one component may include, for example, elastic ear flaps, sheets, or waistbands of a diaper.

[0038] According to certain embodiments of the present invention, a disposable absorbent article includes a disposable diaper, wherein the disposable diaper includes (i) a longitudinal direction and a transverse direction; (ii) a longitudinal centerline and a transverse centerline; (iii) a front region, a rear region and a central region located between the front region and the rear region; and (iv) a pair of elastic ear flaps extending outward from the transversely opposite side edges of the rear region and including the PEL.

[0039] According to certain embodiments of the present invention, a disposable absorbent article includes a disposable diaper, wherein the disposable diaper includes (i) a longitudinal and a transverse direction; (ii) a longitudinal centerline and a transverse centerline; and (iii) a front region, a rear region, and a central region located between the front region and the rear region; wherein at least one of the front region and the rear region has a waist portion including the PEL.

[0040] On the other hand, the present invention provides a method for preparing a PEL, such as those described and disclosed herein. The method may include the following steps: (a) providing or forming a first nonwoven layer; (b) melt-extruding an elastic film onto the first nonwoven layer; (c) pressing an elastic film layer onto the first nonwoven layer to form an intermediate material by passing the elastic film and the first nonwoven layer through a roll gap including a dot-bonding pressure roller, wherein the dot-bonding pressure roller includes a first plurality of discrete protrusions forming a first plurality of discrete adhesive portions between the first nonwoven layer and a first side of the elastic film, and wherein the first plurality of discrete adhesive portions define a first adhesive region and a first adhesive pattern between the first nonwoven layer and the first side of the elastic film, and wherein a first non-adhesive portion of the first nonwoven layer located between the first plurality of discrete adhesive portions is not bonded to the first side of the elastic film; and (d) activating the intermediate material to form the PEL, wherein activating the intermediate material forms deformed portions projecting outward from the xy-plane.

[0041] According to certain embodiments of the invention, the method may further include providing or forming a second nonwoven layer, and laminating the first nonwoven layer, the elastic film, and the second nonwoven layer together. For example, the elastic film may be located or positioned between, and / or adjacent to, the first and second nonwoven layers. The method may include laminating the first nonwoven layer, the elastic film, and the second nonwoven layer together by passing them through a roll gap. As described above, the roll gap may include a dot-bonding pressure roller that also forms a second plurality of discrete bonding sites between the second nonwoven layer and the second side of the elastic film. Alternatively, the roll gap may be defined by two separate dot-bonding pressure rollers through which the first nonwoven layer, the elastic film, and the second nonwoven layer pass. In any case, the second plurality of discrete bonding sites define a second bonding region and a second bonding pattern between the second nonwoven layer and the second side of the elastic film, and wherein a second non-bonded portion of the second nonwoven layer located between the second plurality of discrete bonding sites is not bonded to the second side of the elastic film.

[0042] According to certain embodiments of the invention, the step of activating the intermediate material may include forming deformed portions projecting outward from the xy-plane in the first and second nonwoven layers. According to certain embodiments of the invention, activating the intermediate material may include progressively stretching the intermediate material longitudinally, laterally, or both. According to certain embodiments of the invention, activation may be performed in a single step. Alternatively, activation may be performed in a series of multiple activation steps. For example, the intermediate material may be progressively stretched in an initial activation step, followed by subsequent activation steps. For example, the intermediate material may undergo 2 to 5 individual transverse stretching activation steps (e.g., 2, 3, 4, or 5) and / or 2 to 5 individual longitudinal stretching activation steps (e.g., 2, 3, 4, or 5).

[0043] Figure 5 This is a schematic diagram illustrating the effect of the activation step in forming PEL 1 from intermediate material 3 according to certain embodiments of the present invention. Figure 5 As shown, the intermediate material 3 may include first and second bonding sites, but may not have outwardly protruding deformable portions, while the outwardly protruding deformable portions 14 and 34 may be formed by an activation step.

[0044] According to certain embodiments of the invention, the dot-bonding pressure roller comprises a rubber material or a metal material. By way of example only, the roller gap may include both the dot-bonding pressure roller and the backing roller. For example, the backing roller may include a roller with a smooth surface.

[0045] According to certain embodiments of the invention, the roll gap has a roll gap pressure of about 0 to about 15 psi, for example, at least about any of the following: 0, 2, 3, 5, 6, and 8 psi, and / or at most about any of the following: 15, 14, 12, 10, and 8 psi. Alternatively or additionally, the compression provided by the roll gap can be controlled by providing a small gap between the pressure roll and the backing roll (e.g., a rubber roll). For example, the gap may be slightly smaller than the total thickness of the material (e.g., a laminate or composite material).

[0046] According to certain embodiments of the invention, the method may include preheating the first nonwoven layer, the second nonwoven layer, or both prior to the lamination step. For example, preheating the first nonwoven layer, the second nonwoven layer, or both may include heating the material in question to a temperature close to or slightly above 25°C; however, this temperature should generally not exceed 50°C to avoid heat damage to the film. Alternatively or additionally, the first nonwoven layer, the second nonwoven layer, or both may be activated prior to the lamination step. Alternatively or additionally, the method may include the step of forming a plurality of holes extending through the PEL. If a plurality of holes are present, the plurality of holes may define the open area of ​​the PEL to be from about 2% to about 30%, for example at least about any one of the following: 2, 3, 5, 6, 8, 10, 12, 14, and 15%, and / or at most about any one of the following: 30, 28, 26, 25, 24, 22, 20, 18, 16, and 15%.

[0047] Example This disclosure is further illustrated by the following embodiments and should in no way be construed as limiting. That is, the specific features described in the following embodiments are merely illustrative and not limiting.

[0048] Example Group 1 The PEL according to certain embodiments of the present invention was compared with several commercially available materials for ear applications or diaper sheets. The PEL was made of a 30 gsm elastic film sandwiched between two layers of nonwoven material. Each layer of nonwoven material was 15 gsm spunbond (e.g., Kamisoft from Berry Global, USA). This PEL was compared with commercially available elastic sidesheets made of a 50 gsm elastic film sandwiched between two layers of 30-35 gsm spunlace nonwoven material or 22 gsm carded nonwoven material. Commercial samples were prepared by adhesive lamination or ultrasonic lamination.

[0049] Table 1 below provides a summary of the measured physical properties of PEL and the commercially available materials for comparison. Figure 6 The load versus strain diagrams of PELs or elastic sheets commercially used as disposable absorbent articles (e.g., diapers) and contrast laminates are shown.

[0050] Table 1 Example Group 2 The PEL according to certain embodiments of the present invention was compared with several commercially available materials for ear applications or diaper sheets. The PEL was made of a 30 gsm elastic film sandwiched between two layers of nonwoven material. Each layer of nonwoven material was 15 gsm spunbond (e.g., Kamisoft from Berry Global, USA). This PEL was compared with commercially available elastic sidesheets made of a 50 gsm elastic film sandwiched between two layers of 30-35 gsm spunlace nonwoven material or 22 gsm carded nonwoven material. Commercial samples were prepared by adhesive lamination or ultrasonic lamination.

[0051] Table 2 below provides a summary of the measured physical properties of PEL and the comparative commercially available materials. Figure 7 The load versus strain diagrams of PEL and contrast laminates are shown for use in commercially available disposable absorbent belts (e.g., diapers). Figure 8 The diagram shows the tensile strength of the PEL (polyelasticity) of a belt commercially used as a disposable absorbent product (e.g., diaper) and compares the tensile strength of the laminated material with strain. Figure 9 The load versus strain diagrams of PEL and contrast laminates are shown for use in commercially available disposable absorbent belts (e.g., diapers). Figure 10 The diagram shows the tensile strength of the PEL (polyelastic elastomer) and the tensile strength of the laminated material compared to strain in a belt commercially used as a disposable absorbent product (e.g., diaper).

[0052] Table 2 These and other modifications and variations can be made to the invention by those skilled in the art without departing from the spirit and scope of the invention, which is more specifically set forth in the appended claims. Furthermore, it should be understood that aspects of the various embodiments can be interchanged, in whole or in part. Moreover, those skilled in the art will understand that the foregoing description is merely exemplary and is not intended to limit the invention as further described in these appended claims. Therefore, the spirit and scope of the appended claims should not be limited to the exemplary descriptions of the versions contained herein.

Claims

1. A point-bonded extruded laminate (PEL), comprising: (a) First nonwoven layer; (b) Elastic membrane; (c) Adhere the first nonwoven layer to a first plurality of discrete adhesive portions on a first side of the elastic membrane, wherein the first plurality of discrete adhesive portions define a first adhesive region and a first adhesive pattern between the first nonwoven layer and the first side of the elastic membrane; as well as (d) A first non-adhesive portion of the first nonwoven layer located between the first plurality of discrete adhesive portions, wherein the first non-adhesive portion of the first nonwoven layer is not adhered to the first side of the elastic membrane.

2. The PEL according to claim 1, wherein the PEL further comprises a second nonwoven layer, wherein, The elastic membrane is located between the first nonwoven layer and the second nonwoven layer.

3. The PEL of claim 2, further comprising a second plurality of discrete adhesive portions for bonding the second nonwoven layer to a second side of the elastic membrane, wherein the plurality of second discrete adhesive portions define a second adhesive region and a second adhesive pattern between the second nonwoven layer and the second side of the elastic membrane, and a second unbonded portion of the second nonwoven layer is located between the second plurality of discrete adhesive portions, wherein the second unbonded portion of the second nonwoven layer is not bonded to the second side of the elastic membrane.

4. The PEL according to claim 3, wherein, The first nonwoven layer, the second nonwoven layer, or both of them include spunbond nonwoven materials, carded nonwoven materials, meltblown nonwoven materials, spunlace nonwoven materials, or any combination thereof.

5. The PEL according to claim 4, wherein, The first nonwoven layer, the second nonwoven layer, or both comprise a basis weight of about 3 gsm to about 50 gsm, for example, at least about any of the following: 3, 5, 9, 10, 12, and 15 gsm, and / or at most about any of the following: 50, 45, 40, 35, 30, 25, 20, and 15 gsm.

6. The PEL according to claims 3-5, wherein, The first non-adhesive portion, the second non-adhesive portion, or at least a portion thereof includes a deformable portion protruding outward from the xy plane, wherein the deformable portion has an average height of about 1 mm to about 10 mm, for example, at least about any of the following: 1, 2, 3, 4 and 5 mm, and / or at most about any of the following: 10, 9, 8, 7, 6 and 5 mm.

7. The PEL according to claims 3-6, wherein, The first adhesive region, the second adhesive region, or both comprise from about 5% to about 40%, for example at least about any one of the following: 5, 6, 8, 10, 12, 15, 18 and 20%, and / or at most about any one of the following: 40, 38, 35, 32, 30, 28, 25, 22 and 20%.

8. The PEL according to claims 1-7, wherein, The elastic membrane has an average thickness of about 10 micrometers to about 300 micrometers, for example, at least about any of the following: 10, 15, 20, 50, 80, 100, 120 and 150 micrometers, and / or at most about any of the following: 300, 250, 200 and 150 micrometers.

9. The PEL according to claim 8, wherein, The elastic membrane comprises 1 to 8 individual layers, for example, at least about any of the following: layers 1, 2, 3 and 4, and / or at most about any of the following: layers 8, 7, 6, 5 and 4.

10. The PEL according to claims 1-9, wherein, The PEL has no adhesive.

11. The PEL according to claims 1-10, wherein, The PEL has at least about 80% membrane coverage, for example at least about any of the following: 80, 85 and 90%, and / or at most about any of the following: 100, 99, 98, 97, 96, 95, 94, 93, 92, 91 and 90%.

12. A disposable absorbent article, comprising: A disposable diaper comprising at least one component containing a PEL according to any one of claims 1-11.

13. The article of claim 12, wherein at least one component of the article comprises an elastic ear piece, a sheet, or a belt.

14. The article of claim 13, wherein (A) the disposable diaper comprises (i) a longitudinal direction and a transverse direction; (ii) a longitudinal centerline and a transverse centerline; (iii) a front region, a rear region, and a central region located between the front region and the rear region; (iv) a pair of elastic ear flaps extending outward from the transversely opposite sides of the rear region and including the PEL; or (B) the disposable diaper comprises (i) a longitudinal direction and a transverse direction; (ii) a longitudinal centerline and a transverse centerline; and (iii) a front region, a rear region, and a central region located between the front region and the rear region; wherein at least one of the front region and the rear region has a waist portion including the PEL.

15. A method for preparing a point-bonded extruded laminate (PEL), the method comprising: (a) Providing or forming a first nonwoven layer; (b) The elastic membrane is melt-extruded onto the first nonwoven layer; (c) The elastic film is pressed onto the first nonwoven layer to form an intermediate material by passing the elastic film and the first nonwoven layer through a gap including a dot-bonding pressure roller, wherein the dot-bonding pressure roller includes a first plurality of discrete protrusions forming a first plurality of discrete bonding portions between the first nonwoven layer and a first side of the elastic film, and wherein the first plurality of discrete bonding portions define a first bonding area and a first bonding pattern between the first nonwoven layer and the first side of the elastic film, and wherein a first non-bonded portion of the first nonwoven layer located between the first plurality of discrete bonding portions is not bonded to the first side of the elastic film; as well as (d) Activating the intermediate material to form the PEL, wherein activating the intermediate material forms a deformed portion protruding outward from the xy plane.

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