Laminate bond, and method and apparatus for bonding substrate to form laminate

Abstract

The present disclosure relates to bonding together a first substrate and a second substrate with an adhesive that is substantially free of a tackifier. A layer of a substantially tackifier-free adhesive may be applied to the first surface of the second substrate to define an adhesion region, and the first substrate is positioned on the adhesion region of the second substrate to form a laminate. The first substrate and the second substrate are pressed against each other in the adhesion zone such that the substantially tackifier-free adhesive permeates into the first substrate and the second substrate. A first portion of the layer of adhesive permeates into the first substrate and a second portion of the layer of adhesive permeates into the second substrate. A central portion between the first portion and the second portion of the layer of adhesive separates the second surface of the first substrate from the first surface of the second substrate.

Description

Technical Field

[0001] This disclosure relates to methods for manufacturing absorbent articles, and more specifically to apparatus and methods for bonding a substrate that can be used as a component of an absorbent article. Background Technology

[0002] Various types of disposable absorbent products, such as diapers, sanitary napkins, and panty liners, can be assembled along an assembly line by adding components to and otherwise modifying the advancing continuous material fiber web. The material fiber web and components used to manufacture diapers may include: a backsheet, a topsheet, an absorbent core, front and / or back flaps, fastening components, and various types of elastic fiber webs and components such as leg elastic components, blocking leg elastic components, and waist elastic components. The material fiber web and components used to manufacture sanitary napkins and / or panty liners may include: a backsheet, a topsheet, a second topsheet, absorbent core components, release paper wrapping, etc. After the desired components are assembled, the advancing fiber web and components undergo a final cutting process to separate the fiber web into discrete absorbent products. Absorbent products may also sometimes be folded and / or individually wrapped.

[0003] When manufacturing absorbent articles, various components and / or propulsion material webs can be bonded together in various ways, such as with adhesives and / or mechanical bonding techniques. Flange-type trouser diapers (an article design using discrete patches attached to the front or back band, which act as hinges in the wearing configuration) may require a peel-off bond that must withstand product tension (all elastic components / full band width) at body temperature for a certain duration, such as, for example, 8 hours or more during overnight wear. Because such products are constructed with discrete patches, it may be advantageous to use adhesives instead of certain mechanical bonding methods (such as pressure, thermal conduction, heat convection, ultrasound, or laser) to create the flange bond. Mechanical side-seam / flange bonding can be configured to weld or melt polymer / nonwoven layers together, requiring integration into a delivery device for spacing the individual patches. A potential solution to this need is to directly integrate vacuum into the bonding equipment to simultaneously control and bond the patches to the product. This process configuration can result in complex and expensive bonding equipment that simultaneously bonds / solders and conveys discrete patches. Furthermore, conventional bonding methods may require relatively long dwell or energy transfer times to produce sufficiently strong seam or flange bonds. This leads to manufacturing configurations where the product needs to be wrapped around large rollers, or alternatively, where the fiber web or product may need to be accumulated and the speed of the fiber web through the seam / flange bonding equipment may be slowed. Due to relatively large equipment and / or more space or production speed limitations, requirements such as relatively large rollers or fiber web accumulation to slow down the fiber web and increase heating / dwelling times can result in relatively high production costs.

[0004] A potential solution to the aforementioned problems would be to form the flange bond using an adhesive. Using an adhesive would allow the delivery of the flange patch and the flange bonding to occur simultaneously, such as when the adhesive on the patch or receiving fiber web contacts another fiber web surface. This could help eliminate the need for long heat transfer residence times during bond formation and the need for vacuum control of the patch. However, current industrial hot melt adhesives and application methods may be insufficient to provide flange bonds that meet or exceed some requirements for resistance to peel forces under sustained abrasion at body temperature.

[0005] Furthermore, some bonding operations use hot melt adhesives to bond substrates together, which remain tacky even after cooling. Using such adhesives to bond discrete parts to other substrates can present various challenges in some types of assembly operations. For example, in some assembly operations, a first continuous substrate may be cut into discrete parts, such as a belt. The discrete belts can then be bonded to a continuous substrate, such as a top sheet. Continuing with reference to the belt and top sheet bonding operation illustrated as an example, adhesive can be applied to either or both of the discrete belt and the top sheet. When adhesive is applied to the discrete belt before being combined with the top sheet, the applied adhesive can migrate from the belt and contaminate material handling equipment, such as knives, rollers, and conveyors used to place the belt onto the top sheet. This contaminated adhesive can also migrate to other substrates and components of the assembled article. Instead of applying adhesive to the belt, it can be applied to the top sheet before being combined with the belt. Therefore, the adhesive can be applied to the top sheet in the form of discrete patches, the size of which is set to be related to or matched to the size of the belt. This operation requires very precise placement of the belt onto the discrete adhesive patches. Misalignment of the belt on the adhesive can result in parts of the belt not being bonded, and can also lead to areas of exposed adhesive. Furthermore, the exposed, sticky adhesive may unintentionally bond other components together. For example, in subsequent assembly operations, the combined belt and top piece can be combined with other advancing substrates and / or components to produce discrete absorbent articles that are folded and packaged. Thus, the absorbent article can become bonded to itself in a folded configuration.

[0006] Therefore, it would be beneficial to provide a method and apparatus for bonding a substrate to another substrate to which an adhesive is applied, so as to bond the substrate without the negative effects associated with exposed adhesive that remains tacky during subsequent assembly operations, while also providing an adhesive portion having a construction that provides strength to help meet product integrity requirements, including peel resistance for a certain duration at body temperature. Summary of the Invention

[0007] In one aspect, a method of bonding a substrate includes: providing a first substrate including a first surface and an opposing second surface; providing a second substrate including a first surface and an opposing second surface; applying a layer of a substantially tackifier-free adhesive to the first surface of the second substrate to define an adhesion region; positioning the second surface of the first substrate on the adhesion region of the second substrate; and pressing the first substrate and the second substrate together in the adhesion region such that a first portion of the substantially tackifier-free adhesive layer enters the first substrate, and a second portion of the substantially tackifier-free adhesive layer enters the second substrate, wherein the first portion of the substantially tackifier-free adhesive layer penetrates through the second surface of the first substrate, wherein the second portion of the substantially tackifier-free adhesive layer penetrates through the first surface of the second substrate, and the second surface of the first substrate and the first surface of the second substrate are separated from each other by a central portion of the substantially tackifier-free adhesive layer.

[0008] On the other hand, the absorbent article comprises: a laminate comprising: a first nonwoven fabric including a first surface and an opposing second surface; a second nonwoven fabric including a first surface and an opposing second surface; wherein the first nonwoven fabric is bonded to the second nonwoven fabric in an adhesion region, wherein the adhesion region comprises a layer of a substantially tackifier-free adhesive positioned between the first and second nonwoven fabrics; wherein a first portion of the substantially tackifier-free adhesive layer permeates the second surface of the first nonwoven fabric; wherein a second portion of the substantially tackifier-free adhesive layer permeates the first surface of the second nonwoven fabric; and wherein in the adhesion region, the second surface of the first nonwoven fabric is separated from the first surface of the second nonwoven fabric by a central portion of the substantially tackifier-free adhesive layer, wherein in the first region of the adhesion region, the first portion of the substantially tackifier-free adhesive interweaves with the fibers between the first and second surfaces of the second nonwoven fabric, and with the fibers between the first and second surfaces of the first nonwoven fabric. Attached Figure Description

[0009] Figure 1A This is a partial cutaway plan view of an absorbent article in the form of an adhesive diaper, which may include one or more substrates bonded according to this disclosure, wherein the portion of the diaper facing away from the wearer is oriented toward the observer.

[0010] Figure 1B yes Figure 1A A plan view of an absorbent article, which may include one or more substrates bonded according to the present disclosure, wherein the portion of the diaper facing the wearer is oriented toward the observer.

[0011] Figure 2AThis is a front perspective view of an absorbent article, which may include one or more substrates bonded according to this disclosure.

[0012] Figure 2B yes Figure 2A Front view of the absorbent material.

[0013] Figure 2C yes Figure 2A Rear view of the absorbent material.

[0014] Figure 3 This is a schematic side view of an apparatus for assembling laminates using adhesives that contain virtually no tackifiers.

[0015] Figure 4 This is a left-hand view of a device used to assemble laminates using adhesives that contain virtually no tackifiers.

[0016] Figure 5A For along Figure 4 A side view of the first configuration of the first substrate, second substrate, adhesion zone and laminate, taken by section 5A-5A.

[0017] Figure 5B For along Figure 4 The side view of the second configuration of the first substrate, the second substrate, the adhesion region, and the laminate, taken by the section 5B-5B.

[0018] Figure 5C For along Figure 4 A side view of the first substrate, second substrate, adhesion zone, and third configuration of the laminate, taken from section 5C-5C.

[0019] Figure 6 This is a left-hand view of a device used to assemble laminates using adhesives that contain virtually no tackifiers.

[0020] Figure 7A For along Figure 6 The first configuration of the propulsion, including the first substrate, the second substrate, the adhesion zone, and the laminate, is shown in the section 7A-7A.

[0021] Figure 7B For along Figure 6 The side view of the second configuration of the propulsion, including the first substrate, the second substrate, the adhesion zone, and the laminate, taken by the section 7B-7B.

[0022] Figure 8 This is a schematic diagram of a diaper assembly method with an elastomer laminate.

[0023] Figure 8A This is a schematic diagram of a second diaper trouser assembly method with an elastomer laminate.

[0024] Figure 9 This is a detailed view of the side seam.

[0025] Figure 10 It is along Figure 9 The side view of the side seam cut by the 10-10 section.

[0026] Figure 11 It is along Figure 4 , Figure 6 and Figure 9 Detailed cross-sectional view of the bonding structure between the substrates, taken from line 11-11.

[0027] Figure 12 It is applied between two nonwoven substrates Figure 11 Detailed view of the adhesive structure.

[0028] Figure 13 This is a scanning electron microscope (“SEM” photograph of a cross-sectional view of an example adhesive portion comprising a layer of adhesive that is substantially free of tackifier between a first nonwoven fabric and a second nonwoven fabric.

[0029] Figure 14A It is applied between two nonwoven substrates Figure 11 A detailed view of the bonding structure, wherein one of the nonwoven substrates includes a meltblown layer.

[0030] Figure 14B It is applied between two nonwoven substrates Figure 11 A detailed view of the bonding structure, in which both nonwoven substrates include meltblown layers. Detailed Implementation

[0031] The following definitions of terms will help in understanding this disclosure:

[0032] "Absorbent articles" in this document refers to consumer products whose primary function is to absorb and retain soil and waste. Absorbent articles may include sanitary napkins; tampons; panty liners; interlabial devices; wound dressings; wipes; disposable diapers, including adhesive diapers and diaper pants, inserts for diapers with reusable outer covers, adult incontinence diapers, adult incontinence liners, and adult incontinence pants. The term "disposable" in this document is used to describe absorbent articles that are not generally intended to be washed or otherwise restored to or reused as absorbent articles (e.g., they are intended to be discarded after a single use and may also be constructed to be recyclable, compostable, or disposed of in other environmentally compatible ways).

[0033] The term "adhesive diaper" (also known as "open diaper") refers to a disposable absorbent product that has an initial front waist area and an initial back waist area that are not secured, pre-secured, or connected to each other during packaging before being worn by the wearer. Adhesive diapers can be folded around a lateral centerline, with the interior of one waist area contacting the interior of the opposite waist area surface-to-surface without securing or connecting the waist areas together. Examples of various suitable configurations of adhesive diapers are disclosed in U.S. Patent Nos. 5,167,897, 5,360,420, 5,599,335, 5,643,588, 5,674,216, 5,702,551, 5,968,025, 6,107,537, 6,118,041, 6,153,209, 6,410,129, 6,426,444, 6,586,652, 6,627,787, 6,617,016, 6,825,393, and 6,861,571; and U.S. Patent Publications Nos. 2013 / 0072887 A1, 2013 / 0211356 A1, and 2013 / 0306226 A1, all of which are incorporated herein by reference.

[0034] The term "pants" (also known as "training pants," "pre-closed diapers," "diaper pants," "pants-style diapers," and "over-the-leg diapers") refers herein to a disposable absorbent article having a continuous perimeter waist opening and continuous perimeter leg openings, designed for use by an infant or adult wearer. Pants may be configured to have a continuous or closed waist opening and at least one continuous closed leg opening before the article is worn on the wearer. Pants may be pre-formed or pre-fastened using a variety of techniques, including but not limited to using any re-fastening closure and / or permanent closure (e.g., stitching, thermal bonding, pressure welding, adhesives, glue bonding, mechanical fasteners, etc.) to join the parts of the article together. Pants may be pre-formed at any location around the waist region of the article (e.g., side-fastened or seamed, front waist-fastened or seamed, back waist-fastened or seamed). Examples of various configurations of diaper pants are disclosed in U.S. Patent Nos. 4,940,464, 5,092,861, 5,246,433, 5,569,234, 5,897,545, 5,957,908, 6,120,487, 6,120,489, 7,569,039 and U.S. Patent Publications Nos. 2003 / 0233082 A1, 2005 / 0107764 A1, 2012 / 0061016 A1, 2012 / 0061015 A1, 2013 / 0255861 A1, 2013 / 0255862 A1, 2013 / 0255863 A1, 2013 / 0255864 A1 and 2013 / 0255865. In A1, all of these patents are incorporated herein by reference.

[0035] The term "feminine hygiene products" refers to disposable absorbent articles used by women for menstrual protection. Such feminine hygiene products may include sanitary napkins, tampons, interval products, incontinence devices, and panty liners. Non-limiting examples of panty liners and sanitary napkins include those disclosed in U.S. Patent Nos. 4,324,246, 4,463,045, 4,342,314, 4,556,146, 4,589,876, 4,687,478, 4,950,264, 5,009,653, 5,267,992, and 6,004,893, all of which are incorporated herein by reference.

[0036] "Elasticity," "elastic body," or "elastic material" means that a material exhibits elastic properties, including any material that, when a force is applied to its initial relaxed length, is able to stretch or elongate to a length greater than 10% of its initial length, and will substantially return to approximately its initial length when the applied force is released.

[0037] As used herein, the term "connection" includes a configuration in which an element is directly fixed to another element by directly attaching the element to the other element, and a configuration in which an element is indirectly fixed to another element by attaching the element to an intermediate member (which in turn is attached to the other element).

[0038] The term "substrate" is used herein to describe a material that is primarily two-dimensional (i.e., in the XY plane) and whose thickness (in the Z direction) is relatively small (i.e., 1 / 10 or less) compared to its length (in the X direction) and width (in the Y direction). Non-limiting examples of substrates include fiber webs, one or more layers of fibrous material, nonwovens, membranes, and foils such as polymer films or metal foils. These materials may be used alone or may comprise two or more layers laminated together. Thus, a fiber web is a substrate.

[0039] The term "nonwoven fabric" herein refers to materials made from continuous (long) filaments (fibers) and / or discontinuous (short) filaments (fibers) by processes such as spunbond, meltblown, and carding. In some configurations, nonwoven fabrics may include polyolefin-based nonwoven fabrics, including but not limited to nonwoven fabrics having polypropylene fibers and / or polyethylene fibers and / or bicomponent fibers containing polyolefins. Non-limiting examples of suitable fibers include spunbond, spunbond, meltblown, spunmelt, solvent spinning, electrospinning, carding, membrane fibrillation, melt-film fibrillation, air-jet spinning, dry-laying, wet-laid short fibers, and other nonwoven fiber web materials formed partially or entirely from polymer fibers as known in the art, and feasible combinations thereof. Nonwoven fabrics do not have woven filaments or braided filament patterns. It should be understood that nonwoven fabrics with various basis weights can be used according to the methods described herein. For example, some nonwoven fabrics may have a basis weight of at least about 8 gsm, 12 gsm, 16 gsm, 20 gsm, 25 gsm, 40 gsm, or 65 gsm. Some nonwoven fabrics may have a basis weight of about 8 gsm to about 65 gsm, specifically describing all 1 gsm increments within the above ranges and all ranges formed therefrom.

[0040] It should be understood that membranes with various basis weights can be used according to the methods described herein. For example, some membranes may have a basis weight of at least about 8 gsm, 12 gsm, 16 gsm, 20 gsm, 25 gsm, 40 gsm, or 60 gsm. Some membranes may have a basis weight of about 8 gsm to about 60 gsm, with all 1 gsm increments within the above ranges and in all ranges formed therefrom specifically listed.

[0041] The term "machine orientation" (MD) is used in this document to refer to the direction of material flow in a process. Furthermore, the relative placement and movement of material can be described as flowing through the process from upstream to downstream in the machine orientation.

[0042] The term “lateral” (CD) is used in this document to refer to a direction that is approximately perpendicular to the direction of the machine.

[0043] The term "tackifier-free adhesive" is used herein to refer to adhesive compositions comprising polymers and / or copolymers, wherein the adhesive composition contains no or lacks a tackifier. Examples of such tackifier-free adhesives are disclosed in U.S. Patent Publications 2019 / 0322900 A1, 2019 / 0322901 A1, 2019 / 0322909 A1, 2019 / 0321241 A1, 2019 / 0321242 A1, 2020 / 0047420 A1, and 2020 / 0108167 A1, all of which are incorporated herein by reference.

[0044] As used herein, the terms “without”, “containing”, etc., indicate that the adhesive composition does not possess, in a manner exceeding the background level of trace amounts, the given material, component, or property following these qualifiers; that the amount of the material or component would not cause harm or irritation to a consumer typically associated with that material or component; or that the material or component was not intentionally added to the adhesive composition. In some applications, “without” and “containing” may mean that a measurable amount of the material or component is absent. For example, some forms of adhesive compositions may not contain a measurable amount of tackifier.

[0045] "Adhesives that are substantially free of tackifiers" is used herein to refer to adhesive compositions comprising polymers and / or copolymers, wherein the adhesive composition contains less than 10% by weight of tackifier. Therefore, "adhesives that are free of tackifiers" is also "adhesives that are substantially free of tackifiers".

[0046] The term "tackifier" refers to those conventional tackifier resins commonly available in the adhesives field and industry for use in typical hot melt adhesives. Examples of conventional tackifier resins include aliphatic hydrocarbon resins, aromatic-modified aliphatic hydrocarbon resins, hydrogenated polycyclopentadiene resins, polycyclopentadiene resins, rosin, rosin esters, wood rosin, wood rosin esters, tall oil rosin, tall oil rosin esters, polyterpenes, aromatic-modified polyterpenes, terpene-phenolic resins, aromatic-modified hydrogenated polycyclopentadiene resins, hydrogenated aliphatic resins, hydrogenated aliphatic aromatic resins, hydrogenated terpenes and modified terpenes, and hydrogenated rosin esters.

[0047] Various aspects of this disclosure relate to methods and apparatus for bonding substrates used in adhesive absorbent articles, and more specifically, to methods and apparatus for bonding a first substrate and a second substrate together with a hot melt adhesive that is substantially free of tackifiers. When cooled to a solid state, this substantially tack-free adhesive exhibits relatively low tack. Furthermore, the substantially tack-free adhesive can be used in bonded structures that provide strength to help meet product integrity requirements, including resistance to peeling for a sustained period at body temperature.

[0048] As described below, a first substrate includes a first surface and an opposing second surface, and a second substrate includes a first surface and an opposing second surface. A layer of substantially tack-free adhesive may be applied to the first surface of the second substrate to define an adhesion region. The first substrate is positioned on the adhesion region of the second substrate to form a laminate. The substantially tack-free adhesive is located between the second surface of the first substrate and the first surface of the second substrate. Furthermore, the first and second substrates may be pressed against each other in the adhesion region to facilitate penetration of the substantially tack-free adhesive into both the first and second substrates. As discussed in more detail below, pressing the first and second substrates against each other in the adhesion region allows a first portion of the substantially tack-free adhesive layer to enter the first substrate, and a second portion of the substantially tack-free adhesive layer to enter the second substrate. However, the first portion of the substantially tack-free adhesive layer does not completely penetrate through the thickness of the first substrate, and the second portion of the substantially tack-free adhesive layer does not completely penetrate through the thickness of the second substrate. Furthermore, a central portion of the layer between the first and second portions of the substantially tack-free adhesive layer separates the second surface of the first substrate and the first surface of the second substrate from each other.

[0049] When the first and second substrates are configured as nonwovens, the penetration of a substantially tackifier-free adhesive into the nonwovens helps strengthen the bond between the nonwovens by enabling the substantially tackifier-free adhesive to interweave and bond with the fibers within the nonwovens. Furthermore, the central region of the layer may have a solid thickness of a substantially tackifier-free adhesive, which may be void-free or cavity-free, or at least largely void-free or cavity-free. Therefore, the central portion of the bond can help bear and / or redistribute the load applied to the bond. Thus, the bond between substrates with this structure can help provide sufficient strength to withstand sustained peel forces by relying on fiber encapsulation and the cohesive strength of the solid central region. As described below, the bond with this configuration can be formed by combining a layer of substantially tackifier-free adhesive with sufficient basis weight and compressive pressure to help ensure that the substantially tackifier-free adhesive fully penetrates the substrate to encapsulate the fiber diameter. Compressive pressure can also, for example, prevent the substantially tackifier-free adhesive from completely penetrating through the substrate.

[0050] It should be understood that the systems and methods disclosed herein are applicable to working with various types of conversion processes and / or machines, such as, for example, absorbent article manufacturing and assembly processes. The methods and apparatus are discussed below in the context of diaper manufacturing. For purposes of illustration, Figure 1A and Figure 1B An example of an absorbent article 100 is shown, which can be assembled according to the methods and apparatus disclosed herein. Specifically, Figure 1AAn example plan view of an absorbent article 100 constructed as an adhesive diaper 100T is shown, wherein the portion of the diaper facing away from the wearer is oriented towards the observer. Figure 1B A plan view of diaper 100 is shown, wherein the portion of the diaper facing the wearer is oriented toward the observer. Figure 1A and Figure 1B The adhesive diaper 100T shown includes an absorbent base structure 102, a first rear side panel 104 and a second rear side panel 106; and a first front side panel 108 and a second front side panel 110.

[0051] like Figure 1A and Figure 1B As shown, the absorbent article 100 and the base structure 102 each include a first waist region 116, a second waist region 118, and a crotch region 119 disposed between the first waist region and the second waist region. The first waist region 116 may be configured as a front waist region, and the second waist region 118 may be configured as a rear waist region. In some configurations, the length of each of the front waist region, the rear waist region, and the crotch region may be 1 / 3 of the length of the absorbent article 100. The absorbent article may also include a laterally extending front waist edge 120 in the front waist region 116 and a longitudinally opposing and laterally extending rear waist edge 122 in the rear waist region 118. For the purpose of providing a frame of reference for this discussion, Figure 1A and Figure 1B The diaper 100T is shown with a longitudinal axis 124 and a lateral axis 126. The longitudinal axis 124 extends through the midpoint of the front waist edge 120 and through the midpoint of the back waist edge 122. The lateral axis 126 extends through the midpoint of the first longitudinal or right side 128 and through the midpoint of the second longitudinal or left side 130.

[0052] like Figure 1A and Figure 1B As shown, diaper 100 includes an inner body-facing surface 132 and an outer clothing-facing surface 134. The base structure 102 may include a bottom sheet 136 and a top sheet 138. The base structure 102 may also include an absorbent assembly 140 having an absorbent core 142 disposed between a portion of the top sheet 138 and the bottom sheet 136. As described in more detail below, diaper 100 may also include other feature structures, such as leg elastic members and / or leg bands, elastic waistbands, and / or flaps such as side panels and / or ear flaps, to enhance the fit around the wearer's legs and waist, thereby enhancing the fit around the wearer's legs.

[0053] like Figure 1A and Figure 1BAs shown, the periphery of the base structure 102 may be defined by: a first longitudinal side edge 128, a second longitudinal side edge 130, a first laterally extending end edge 144 disposed in the first waist region 116, and a second laterally extending end edge 146 disposed in the second waist region 118. Both side edges 128 and 130 extend longitudinally between the first end edge 144 and the second end edge 146. Figure 1A As shown, the laterally extending end edges 144 and 146 may form part of a laterally extending front waist edge 120 in the front waist region 116 and part of a longitudinally opposing and laterally extending rear waist edge 122 in the rear waist region 118. The distance between the first lateral end edge 144 and the second lateral end edge 146 may define the spacing length PL of the base structure 102. When the diaper 100 is worn on the wearer's lower body, the front waist edge 120 and the rear waist edge 122 may surround a portion of the wearer's waist. At the same time, the side edges 128 and 130 may surround at least a portion of the wearer's legs. And the crotch region 119 may generally be positioned between the wearer's legs, wherein the absorbent core 142 extends from the front waist region 116 through the crotch region 119 to the rear waist region 118.

[0054] It should also be understood that part or all of the diaper 100 may also be made laterally stretchable. This additional stretch helps the diaper 100 conform to the wearer's body during movement. This additional stretch also helps, for example, users of diapers 100 including those with a base structure 102 of a specific size before stretching to extend the front waist area 116, back waist area 118, or both waist areas of the diaper 100 and / or base structure 102 to provide additional body coverage for wearers of different sizes, i.e., custom-made diapers for individual wearers. This extension of the waist area can give the absorbent article a generally hourglass shape, and a fitted appearance when worn, provided that the crotch area is less stretched than the waist area.

[0055] As previously mentioned, diaper 100 may include a backing sheet 136. The backing sheet 136 may also define the outer surface 134 of the base structure 102. The backing sheet 136 may be liquid-impermeable (e.g., menstrual flow, urine, and / or loose stools) and may be partially made of a thin plastic film, although other flexible liquid-impermeable materials may also be used. The backing sheet 136 prevents exudates absorbed and contained in the absorbent core from wetting articles such as sheets, pajamas, and underwear that come into contact with diaper 100. The backing sheet 136 may also include woven or nonwoven materials, polymer films such as thermoplastic films of polyethylene or polypropylene, and / or multilayers or composites comprising films and nonwoven materials (e.g., having an inner film layer and an outer nonwoven layer). The backing sheet may also include an elastomeric film. An example backing sheet 136 may be a polyethylene film having a thickness of about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mil). Exemplary polyethylene films are manufactured by Clopay Corporation (Cincinnati, Ohio) under the trade names BR-120 and BR-121, and by Tredegar Film Products (Terre Haute, Ind.) under the trade name XP-39385. The backing sheet 136 may also be embossed and / or roughened to provide a more fabric-like appearance. Furthermore, the backing sheet 136 allows vapor to escape from the absorbent core (i.e., the backing sheet is breathable) while still preventing effluent from penetrating the backing sheet 136. The dimensions of the backing sheet 136 may depend on the dimensions of the absorbent core 142 and / or the specific configuration or size of the diaper 100.

[0056] As described above, diaper 100 may include a top sheet 138. The top sheet 138 may also define all or part of the internal surface 132 of the base structure 102. The top sheet 138 may be soft, loose-feeling, and non-irritating to the wearer's skin. It may be elastically stretched in one or both directions. Furthermore, the top sheet 138 may be liquid-permeable, allowing liquids (e.g., menstrual fluid, urine, and / or loose stools) to permeate its thickness. The top sheet 138 may be made of a variety of materials, such as woven and nonwoven materials; open-cell or hydroformed thermoplastic films; open-cell nonwovens, porous foams; mesh foams; mesh thermoplastic films; and thermoplastic loose fabrics. Woven and nonwoven materials may include natural fibers such as wood fibers or cotton fibers; synthetic fibers such as polyester fibers, polypropylene fibers, or polyethylene fibers; or combinations thereof. If the top sheet 138 includes fibers, the fibers may be processed by spunbonding, carding into a web, wet-laid, melt-blown, hydroentangling, or other methods known in the art.

[0057] Topsheet 138 may be selected from high-loft nonwoven topsheets, perforated membrane topsheets, and perforated nonwoven topsheets. Perforated membrane topsheets allow bodily effluents to pass through but are substantially non-absorbent, and reduce the tendency to allow fluids to flow back and seep back into the wearer's skin. Exemplary perforated membranes may include those described in U.S. Patent Nos. 5,628,097, 5,916,661, 6,545,197, and 6,107,539, all of which are incorporated herein by reference.

[0058] As described above, the diaper 100 may also include an absorbent assembly 140 connected to the base structure 102. For example... Figure 1A and Figure 1B As shown, the absorbent assembly 140 may have a laterally extending front edge 148 in the front waist region 116 and a longitudinally opposing, laterally extending rear edge 150 in the rear waist region 118. The absorbent assembly may have a longitudinally extending right edge 152 and a laterally opposing, longitudinally extending left edge 154, with these two absorbent assembly side edges 152 and 154 extending longitudinally between the front edge 148 and the rear edge 150. The absorbent assembly 140 may additionally include one or more absorbent cores 142 or absorbent core layers. The absorbent core 142 may be at least partially disposed between the top sheet 138 and the bottom sheet 136 and may be formed in various sizes and shapes compatible with diapers. Exemplary absorbent structures used as absorbent cores of this disclosure are described in U.S. Patent Nos. 4,610,678, 4,673,402, 4,888,231, and 4,834,735, all of which are incorporated herein by reference.

[0059] Some absorbent core embodiments may include a fluid storage core comprising a reduced amount of cellulose breathable felt material. For example, such a core may comprise less than about 40%, 30%, 20%, 10%, 5%, or even 1% of cellulose breathable felt material. Such a core may primarily comprise at least about 60%, 70%, 80%, 85%, 90%, 95%, or even about 100% absorbent gelling material, wherein the remainder of the core comprises microfiber adhesive (if applicable). Such cores, microfiber adhesives, and absorbent gelling materials are described in U.S. Patent Nos. 5,599,335, 5,562,646, 5,669,894, and 6,790,798, and U.S. Patent Publications 2004 / 0158212 A1 and 2004 / 0097895 A1, all of which are incorporated herein by reference.

[0060] As previously mentioned, diaper 100 may also include an elastic leg cuff 156 and an elastic waistband 158. It should be understood that the leg cuff 156 may be, and sometimes referred to as, a leg band, side wing, barrier cuff, elastic cuff, or liner cuff. The elastic leg cuff 156 may be constructed in various ways to help reduce leakage of bodily fluids in the leg area. Example leg cuffs 156 may include those described in U.S. Patent Nos. 3,860,003, 4,909,803, 4,695,278, 4,795,454, 4,704,115, and U.S. Patent Publication 2009 / 0312730 A1, all of which are incorporated herein by reference.

[0061] The elastic waistband 158 provides improved fit and restraint, and allows the diaper 100 to stretch and contract elastically to dynamically conform to a portion or area of ​​the wearer's waist. The elastic waistband 158 may extend longitudinally inward from the waist edges 120, 122 of the diaper toward the lateral edges 148, 150 of the absorbent core 142. The diaper 100 may also include more than one elastic waistband 158, for example, having one waistband 158 positioned in the back waist region 118 and one waistband 158 positioned in the front waist region 116, although other embodiments may be constructed using a single elastic waistband 158. The elastic belt 158 ​​can be constructed in a variety of different configurations, including those described in U.S. Patent Nos. 4,515,595 and 5,151,092 and U.S. Patent Publications 2020 / 0375807 A1, 2020 / 0375815 A1, 2021 / 0128366 A1, and 2021 / 0128369 A1, all of which are incorporated herein by reference. In some embodiments, the elastic belt 158 ​​may comprise a material that has been “pre-stressed” or “mechanically pre-stressed” (subjected to a degree of localized mechanical stretching to permanently elongate the material). The material can be pre-stressed using deep embossing techniques known in the art. In some embodiments, these materials can be pre-stressed by guiding the material through an incremental mechanical stretching system as described in U.S. Patent No. 5,330,458. The material is then returned to its substantially unstressed state, thus forming a stretchable, zero-strain stretched material that has at least reached the initial stretch point. Examples of zero-strain materials are disclosed in U.S. Patent Nos. 2,075,189, 3,025,199, 4,107,364, 4,209,563, 4,834,741, and 5,151,092, all of which are incorporated herein by reference.

[0062] like Figure 1BAs shown, the base structure 102 may include longitudinally extending and laterally opposed side wings 160 disposed on the inner surface 132 of the base structure 102 that faces inward and contacts the wearer. Each side wing may have a proximal edge. The side wings may also overlap with the absorbent assembly 140, wherein the proximal edge extends laterally inward from the respective side edges of the absorbent assemblies 152 and 154. In some configurations, the side wings may not overlap with the absorbent assemblies. It should be understood that the side wings may be formed in various ways, such as, for example, by folding portions of the base structure 102 laterally inward (i.e., toward the longitudinal axis 124) to form both the respective side wings and the side edges 128 and 130 of the base structure 102. In another example, the side wings may be formed by attaching one or more additional layers to the base structure at or adjacent to each of the respective side edges. Each of the side wings may be attached to the inner surface 132 of the base structure and / or the absorbent assembly in the side wing attachment area in the front waist region 116 and the rear waist region 118. The side wings may extend to the same longitudinal extent as the absorbent article, or alternatively, the side wings may have a longitudinal extent smaller than that of the absorbent article.

[0063] Adhesive diapers can be manufactured and provided to consumers in a configuration in which the front waist area and the back waist area are not fastened, pre-fastened, or connected to each other during packaging before being worn by the wearer. For example, adhesive diaper 100 can be folded around a lateral centerline, wherein the inner surface 132 of the first waist area 116 contacts the inner surface 132 of the second waist area 118 in a surface-to-surface manner without fastening or connecting these waist areas together. The back side panels 104 and 106 and / or the front side panels 108 and 110 can also be folded laterally inward toward the inner surfaces 132 of the waist areas 116 and 118.

[0064] The diaper 100 may also include fastening elements of various configurations to fasten the front waist area 116 and the back waist area 118 together, thereby forming a closed waistband and leg openings when the diaper is positioned on the wearer. For example, as Figure 1A and 1B As shown, the diaper 100 may include a first fastening member 162 and a second fastening member 164 (also referred to as a tab), which are connected to a first rear side panel 104 and a second rear side panel 106, respectively. The diaper may also include a first front side panel 108 and a second front side panel 110, which may or may not include fastening members.

[0065] Continue to refer to Figure 1A and Figure 1BEach side piece 104, 106 and / or fastening member 162 and 164 may form part of the base structure 102, or may be permanently bonded, adhered, or otherwise directly or indirectly connected to the base structure from the side edges 128 and 130 in one of the front waist region 116 or the rear waist region 118. Alternatively, fastening members 162, 164 may form part of the following pieces and / or side pieces, or may be permanently bonded, adhered, or otherwise directly or indirectly connected to the following pieces (at or near the distal edge of the piece) and / or side pieces (at or near the distal edge of the side piece): first rear piece 104, second rear piece 106, first front side piece 108, second front side piece 110. It should be understood that the fastening members and / or side pieces may be assembled in various ways, such as those disclosed, for example, in U.S. Patent No. 7,371,302, which is incorporated herein by reference. Fastening members 162, 164 and / or side pieces 104, 106, 108, 110 may also be permanently bonded or connected in various ways at or near the side edges 128 and 130 of the base structure 102, such as, for example, by adhesive bonding, acoustic bonding, pressure bonding, thermal bonding or combinations thereof, such as that disclosed, for example, in U.S. Patent No. 5,702,551, which is incorporated herein by reference.

[0066] Now for reference Figure 1B The first fastening member 162 and / or the second fastening member 164 may include various types of releasably engaged fasteners. The first fastening member 162 and / or the second fastening member 164 may also include various types of re-fastening fastening structures. For example, the first fastening member 162 and the second fastening member 164 may include mechanical fasteners 166 in the form of: hook-and-loop fasteners, hook-and-hook fasteners, macro fasteners, buttons, snaps, insert-slot fasteners, tape fasteners, adhesive fasteners, glue fasteners, magnetic fasteners, hermaphroditic fasteners, etc. Examples of fastening systems and / or fastening components 162, 164 are discussed in U.S. Patent Nos. 3,848,594, 4,662,875, 4,846,815, 4,894,060, 4,946,527, 5,151,092, 5,221,274, 6,251,097, 6,669,618, 6,432,098 and U.S. Patent Publications 2007 / 0078427 A1 and 2007 / 0093769 A1, all of which are incorporated herein by reference.

[0067] As previously mentioned, fastening members 162 and 164 can be constructed from various materials and can be configured as a laminated structure. Fastening members 162 and 164 may also be adapted to releasably and / or re-fastenably engage or connect to another portion of the diaper 100. For example, as... Figure 1AAs shown, the diaper 100 may include a connecting area 168, sometimes referred to as a landing area, in a first waist region 116. Thus, when the adhesive diaper 100 is placed on a wearer, fastening members 162 and 164 can be pulled around the wearer's waist and engage with the connecting area 168 in the first waist region 116 to form a closed waistband and a pair of laterally opposed leg openings. It should be understood that the connecting area may be constructed from a separate base that is connected to the base structure 102 of the adhesive diaper. In some embodiments, the connecting area may be integrally formed as part of the backsheet 136 of the diaper 100, or may be formed as part of the first front sheet 108 and the second front sheet 110, as described in, for example, U.S. Patent Nos. 5,735,840 and 5,928,212, all of which are incorporated herein by reference.

[0068] As previously mentioned, the absorbent article 100 can also be constructed as a diaper trouser 100P having a continuous peripheral waist opening and continuous peripheral leg openings. For example, Figure 2A A perspective view of an absorbent article 100 in the form of a diaper trouser 100P in a pre-fastened configuration is shown, and Figures 2B to 2C The front and back views of diaper pants 100P are shown. Diaper pants 100P may include the features described in the reference above. Figure 1A The aforementioned infrastructure 102 and such Figure 2A The annular elastic band 170 is shown. In some embodiments, the first elastic band 172 and the second elastic band 174 are bonded together to form the annular elastic band 170. Thus, diapers can be manufactured with the annular elastic band 174 and provided to the consumer in a configuration where the front waist region 116 and the back waist region 118 of the basic structure 102 are connected to each other, as in packaging, before being worn by the wearer. Therefore, diapers can have a continuous peripheral waist opening 176 and a continuous peripheral leg opening 178, such as... Figure 2AAs shown. Example elastic band 170 configurations are disclosed in U.S. Patent Publications 2018 / 0168878 A1, 2018 / 0168877 A1, 2018 / 0168880 A1, 2018 / 0170027 A1, 2018 / 0169964 A1, 2018 / 0168879 A1, 2018 / 0170026 A1, 2018 / 0168889 A1, 2018 / 0168874 A1, 2018 / 0168875 A1, 2018 / 0168890 A1, 2018 / 0168887 A1, 2018 / 0168892 A1, 2018 / 0168876 A1, and 2018 / 0168891. All of these patent publications, namely A1, 2019 / 0070042 A1, 2019 / 0070041 A1, 2021 / 0282797A1, 2021 / 0275362 A1, 2022 / 0142828 A1 and 2022 / 0362068 A1, are incorporated herein by reference.

[0069] As previously mentioned, the annular elastic band 170 may be defined by a first elastic band 172 connected to the second elastic band 174. Figures 2A to 2C As shown, a first elastic band 172 extends between a first longitudinal side edge 180a and a second longitudinal side edge 180b. A second elastic band 174 extends between a first longitudinal side edge 182a and a second longitudinal side edge 182b. The distance between the first longitudinal side edge 180a and the second longitudinal side edge 180b defines the pitch PL of the first elastic band 172, and the distance between the first longitudinal side edge 182a and the second longitudinal side edge 182b defines the pitch PL of the second elastic band 174. The first elastic band is connected to a first waist region 116 of the base structure 102, and the second elastic band 108 is connected to a second waist region 116 of the base structure 102. Figures 2A to 2C As shown, the opposite end regions of the first elastic band 172 are connected to the opposite end regions of the second elastic band 174 at the first side joint 184 and the second side joint 186, thereby defining the annular elastic band 170, the waist opening 176, and the leg opening 178. It should be understood that the annular elastic band can be formed by connecting the first elastic band to the second elastic band using permanent side joints or by using an openable and reclosable fastening system provided at or near the laterally opposite sides of the band.

[0070] As previously described, absorbent articles can be assembled with various components that can be constructed from the laminates described herein. Therefore, in the context of the preceding discussion, the apparatus and methods described herein can be used to bond substrates configured as continuous substrates and / or discrete components of absorbent article 100. For example, the apparatus and methods described herein can be used to bond substrates to produce a laminate that serves as a top sheet 138; a bottom sheet 136; an absorbent core 140; leg hoops 156; a waist feature 158; side wings 160; side panels 104, 106, 108, 110; a connecting area 168; fastening elements 162, 164, 166; and / or a band 170, or any of these, for use.

[0071] It should be understood that the systems and methods disclosed herein are applicable to working with various types of conversion processes and / or machines. For example, Figure 3 A schematic diagram of a conversion process including a bonding apparatus or system 300 is shown, which bonds a first substrate 200 to a second substrate 202 to form a laminate 204. The first substrate 200 includes a first surface 206 and an opposing second surface 208. In some configurations, the first substrate 200 may also be configured as a discrete piece or part that can be cut or otherwise separated from a continuous first substrate 201. Thus, the shape of the first substrate 200 may be defined by a continuous peripheral edge 210. The second substrate 202 includes a first surface 212 and an opposing second surface 214. In some configurations, the second substrate 202 may be configured as a continuous second substrate advanced in the machine direction MD. The second substrate 202 may also be defined as a width extending laterally CD between a first longitudinal side edge 216 and a second longitudinal side edge 218.

[0072] like Figure 3As shown, the bonding system 300 may include an adhesive applicator 302. During operation, a second substrate 202 is advanced along the machine direction MD. The adhesive applicator 302 then deposits a layer 401 of adhesive 400, which is substantially free of tackifiers, onto a first surface 212 of the advanced second substrate 202 to define an adhesion region 402. The first substrate 200 may be positioned on the adhesion region 402 on the second substrate 202 to define a first region 404 and a second region 406 of the adhesion region 402. In the first region 404 of the adhesion region 402, the substantially tackifier-free adhesive 400 is positioned between a second surface 208 of the first substrate 200 and a first surface 212 of the second substrate 202. And in the second region 406 of the adhesion region 402, the substantially tackifier-free adhesive 400 is not positioned between a second surface 208 of the first substrate 200 and a first surface 212 of the second substrate 202. It should be understood that in some configurations, the adhesive 400, which is essentially free of tackifiers, can be completely covered by the first substrate 200 and the second substrate 202, and therefore, the adhesion region 402 may not include the second region 406.

[0073] Continue to refer to Figure 3 As the laminate 204 progresses to additional downstream, subsequent manufacturing and conversion operations (such as assembly, folding, and / or cutting operations), the substantially tackifier-free adhesive 400 in the second region 406 may remain exposed or otherwise uncovered by the first substrate 200. Such additional subsequent operations are indicated by the dashed arrow “A,” which generally signifies the conversion of the laminate 204 into at least one discrete article 203. Thus, the article 203 may include the substantially tackifier-free adhesive 400 exposed in the second region 406 of the adhesion area 402, wherein the second substrate 202 does not unintentionally become bonded to itself or other substrates and / or machinery during such additional subsequent operations. For example, Figure 3 Additional subsequent operations are illustrated with folding (indicated by dashed arrow "B") the discrete article 203 and the second substrate 202. As a result of the folding, a portion of the first surface 212 of the second substrate 202 may be positioned in direct contact with the first surface 206 of the first substrate 200 and the second region 406 of the adhesion area 402. Subsequently, the substantially tackifier-free adhesive 400 does not adhere to the second substrate 202 and unintentionally holds the article 203 in the folded state. It should be understood that the discrete article 203 can be of various forms and types, such as absorbent articles including feminine hygiene products, diapers, sanitary napkins, and panty liners. It should also be understood that during use of the article, the substantially tackifier-free adhesive 400 in the second region may be exposed to the wearer's skin and / or clothing without unintentionally adhering to the wearer's skin and / or clothing. It should also be understood that the substantially tackifier-free adhesive 400 in the adhesion area 402 may be applied to define various adhesive structures, such as those referenced below. Figure 11 and Figure 12 The subject of discussion.

[0074] It should be understood that various process configurations can be used to bond the first substrate 200 and the second substrate 202 with an adhesive 400 that is substantially free of tackifiers to form the laminate 204 described herein. For example, Figure 4 A schematic diagram of an example configuration of an apparatus 300 that can be used to form a laminate 204 is shown. The apparatus 300 may include a transport assembly 304 configured to transport a first substrate 200 in discrete portion form from a first position P1 to a second position P2 in the machine direction MD. Figure 4 As shown, a continuous first substrate 201 is advanced along the machine direction MD to a transfer assembly 304. The transfer assembly 304 may include a carrier surface 306 and may be adapted to rotate about a first axis 308. The first surface 206 of the advanced continuous first substrate 201 engages with a moving carrier surface 306 at a pickup area 312. As the transfer assembly 304 rotates about the first axis 308 to advance a portion of the continuous first substrate 201, a cutter 314 cuts discrete first substrates 200 from the continuous first substrate 201 at the pickup area 312. It should be understood that the cutter 314 may be constructed in various ways, such as, for example, a blade or a laser.

[0075] Although the conveying assembly 304 is depicted as a rotating drum, it should be understood that the conveying assembly can be constructed in various ways. For example, in some embodiments, the conveying assembly 304 may be in the form of a conveyor belt and / or one or more rollers and / or other types of conveying devices, such as those disclosed, for example, in U.S. Patent Nos. 5,025,910, 5,224,405, 5,556,504, 5,702,551, 6,319,347, 6,450,321, 6,524,423, 6,550,517, 6,604,623, 6,116,317, 6,649,010, 6,722,494, 7,341,087, 7,650,984, 7,770,712, 8,720,666, and 9,737,442, and U.S. Patent Publication 2009 / 0294044 A1, all of which are incorporated herein by reference. In some configurations, the transfer assembly 304 may rotate about a first axis 308 at a constant or variable angular velocity. In some configurations, the carrier surface 306 may move about the first axis 308 at a constant or variable angular velocity and / or at a constant or variable speed. It should also be understood that the carrier surface 306 may advance at a speed equal to or greater than the advancing speed of the continuous first base 201. In some configurations in which the continuous first base 201 has been stretched in the machine direction MD before engaging the transfer assembly 304, the carrier surface 306 may advance at a speed less than the advancing speed of the continuous first base 201. It should also be understood that in some transition operations, the first continuous base 201 and / or the first base 200 may be stretched in the transverse direction CD, such as those disclosed, for example, in U.S. Patent Publications 2020 / 0375807A1, 2021 / 0128366A1, 2020 / 0375815A1, and 2021 / 0128369A1, all of which are incorporated herein by reference. In some configurations, the carrier surface 306 can move about the first axis 308 at a constant or variable distance from it. It should also be understood that the carrier surface 306 may be provided with a variety of numbers of holes of various shapes and sizes and may be in fluid communication with a vacuum system. Furthermore, when moving from the first position P1 to the second position P2, the carrier surface 306 and the first substrate 200 may also rotate or pivot about a second axis of rotation to position the first substrate 200 in a second orientation.

[0076] Continue to refer to Figure 4 The conveying assembly 304 is rotatable about a first axis 308, causing the carrier surface 306 and the first substrate 200 positioned on the carrier surface 306 to move from a first position P1 to a second position P2 about the first axis 308. Then, the first substrate 200 is conveyed to the second substrate 202 at the dropping area 316 to form the laminate 204. See details. Figure 4 and Figure 5A The second substrate 202 is advanced in the machine direction MD past the adhesive applicator 302 and toward the discharge zone 316. The adhesive applicator 302 deposits a layer 401 of adhesive 400, which is substantially free of tackifier, onto the first surface 212 of the second substrate 202 to define an adhesion zone 402 of the second substrate 202. At the discharge zone 316, the first substrate 200 is conveyed from the conveying assembly 304 to position a second surface 208 of the first substrate 200 onto the adhesion zone 402. It should be understood that the carrier surface 306 may be advanced through the discharge zone 316 at various speeds relative to the advancing speed of the second substrate 202. In some configurations, the carrier surface 306 may be advanced through the discharge zone 316 at the same speed as the advancing speed of the second substrate 202. In some configurations, the carrier surface 306 may be advanced through the discharge zone 316 at a slower speed than the advancing speed of the second substrate 202.

[0077] like Figure 4 and Figure 5A As shown, the adhesion region 402 of the laminate 204 may include a first region 404 and a second region 406. An adhesive 400, substantially free of tackifier, is positioned in the first region 404 of the adhesion region 402 between the second surface 208 of the first substrate 200 and the first surface 212 of the second substrate 202. And the adhesive 400, substantially free of tackifier, is not positioned in the second region 406 of the adhesion region 402 between the second surface 208 of the first substrate 200 and the first surface 212 of the second substrate 202.

[0078] It should be understood that the adhesion region 402 and the first substrate 200 can have various shapes. For example, although the adhesion region 402 is generally depicted herein as defining a rectangular shape on the first surface 212 of the second substrate 202, it should be understood that the adhesion region 402 can have a periphery defining a circle, square, oval, elliptical, and various other shapes, which may or may not correspond to the shape defined wholly or partially by the periphery 210 of the first substrate 200. It should also be understood that the adhesion region 402 and the first substrate 200 can have the same shape or can have different shapes.

[0079] It should be understood that the adhesion region 402 and the first substrate 200 may have various sizes relative to each other. For example, as Figure 5A As shown, the first substrate 200 may define a first region A1, and the adhesion region 402 may define a second region A2. In some configurations, the second region A2 may be larger than the first region A1. In some configurations, the first region A1 may be equal to the second region A2. In some configurations, the first region A1 may be larger than the second region A2. It should also be understood that the first substrate 200 may be oriented relative to the second substrate 202 and / or the adhesion region 402 in various ways. For example, as Figure 5BAs shown, the first substrate 200 may be oriented on the second substrate 202 such that a portion of the second surface 208 of the first substrate 200 may not be completely positioned on the first surface 212 and / or the adhesion region 402 of the second substrate 202.

[0080] It should also be understood that the device 300 can be configured to assemble a laminate 204 having a plurality of first substrates 200 and / or second substrates 202 in various orientations. For example, as Figure 5B As shown, the laminate 204 may include a plurality of first substrates 200a, 200b and corresponding adhesion regions 402 respectively disposed on a first edge 216 and a second edge 218 of a second substrate 202 along the machine direction MD. In another example, such as Figure 5C As shown, the laminate 204 may include second substrates 202a, 202b separated from each other in the transverse direction CD, wherein the first substrate 200 is arranged in the machine direction MD and partially positioned on both the second substrates 202a, 202b and the corresponding adhesion regions 402. It should also be understood that the adhesive applicator 302 may be configured to apply a layer 401 of adhesive 400 that is substantially free of tackifier, in order to define a plurality of adhesion regions 402 arranged in the machine direction MD and / or transversely on the second substrate 202, such as, for example... Figures 5A to 5C As shown. In some configurations, the adhesive applicator 302 may be configured to apply a layer 401 of adhesive 400, which is substantially free of tackifier, to either or both of the first substrate 200 and the second substrate 202. It should be understood that... Figures 5A to 5C The arrangement shown can be configured such that an adhesive 400, which is substantially free of tackifier, can be completely covered by the first substrate 200 and the second substrate 202, and therefore, the adhesion area 402 may not include the second region 406.

[0081] The device 300 described herein can also be constructed in various ways to help enhance the adhesion between the first substrate 200 and the second substrate 202 in the adhesion region 402. In some configurations, such as Figure 4 As shown, the first substrate 200 and / or the second substrate 202 may include nonwoven layers that are combined to form a laminate 204. The laminate 204 may then be advanced through a roll gap 318 adapted to press the first substrate 200 and the second substrate 202 together in a first region 404 of the adhesion zone 402 to help a substantially tackifier-free adhesive 400 penetrate into the first substrate 200 and the second substrate 202.

[0082] When the first substrate 200 and the second substrate 202 include a nonwoven layer, the penetration of a substantially tackifier-free adhesive into the nonwoven fabric can cause the substantially tackifier-free adhesive to interweave and bond with the fibers within the nonwoven fabric, thereby helping to strengthen the bond between them. For example, using Figure 4In the configuration shown, the roller gap 318 may be defined between the pressing surface 320 and the carrier surface 306. When the first substrate 200 is conveyed from the conveying assembly 304 to the second substrate 202, pressure is applied to the second surface 214 of the second substrate 202 via the pressing surface 320, and pressure is applied to the first surface 206 of the first substrate 200 via the carrier surface 306. The pressure applied to the first substrate 200 and the second substrate 202 then forces the substantially tackifier-free adhesive 400 in the adhesion region 402 through the first surface 212 of the second substrate 202 and through the second surface 208 of the first substrate 200. Thus, a portion of the substantially tackifier-free adhesive 400 in the first region 404 of the adhesion region 402 may become interwoven with the fibers between the first surface 212 and the second surface 214 of the second substrate 202, and with the fibers between the first surface 206 and the second surface 208 of the first substrate 200, as referenced below. Figure 11 and Figure 12 To be discussed in more detail.

[0083] like Figure 4 As shown, the pressing surface 320 may be defined by the outer peripheral surface 322 of the roller 324, wherein the roller 324 may be adapted to rotate about a second axis of rotation 326. It should be understood that the pressing surface 320 may be constructed in various ways. For example, the pressing surface 320 may be associated with various types of equipment, such as, for example, rotary cams, oscillating tampers, and / or various configurations, such as those disclosed in U.S. Patent Nos. 4,576,600, 6,494,244, 7,452,436, 7,640,962, 7,811,403, and 9,168,182, and U.S. Patent Publication No. 2009 / 0294044 A1, all of which are incorporated herein by reference. Although Figure 4 The roller gap 318 is depicted as being located and defined between the carrier surface 306 of the conveying assembly 304 and the pressing surface 320 of the roller 324. However, it should be understood that the device 300 may be configured to have one or more roller gaps 320 positioned downstream of the discharge area 316, which are adapted to press the first substrate 200 and the second substrate 202 against each other in the adhesion area 402. Such roller gaps may be constructed in various ways and may be defined in various types of devices, such as those discussed herein.

[0084] As previously discussed, the substantially tackifier-free adhesive 400 in the adhesion region 402 can be forced through the first surface 212 of the second substrate 202 and through the second surface 208 of the first substrate 200 by pressure applied to the first substrate 200 and the second substrate 202. For example, Figure 11A detailed cross-sectional view of a layer 401 of adhesive 400, which is substantially free of tackifier, is shown after such pressure is applied to a first substrate 200 and a second substrate 202 to form an adhesive portion 403 between the first substrate 200 and the second substrate 202. Figure 11 As shown, the adhesive portion 403 includes a first portion 401a of a layer 401 of adhesive 400 that is substantially free of tackifier, which has penetrated into the first substrate 200, and a second portion 401b of a layer 401 of adhesive 400 that is substantially free of tackifier, which has penetrated into the second substrate 202. Specifically, the first portion 401a of the layer 401 of adhesive 400 that is substantially free of tackifier has penetrated through the second surface 208 of the first substrate 200, but has not reached or left the first surface 206 of the first substrate 200. And the second portion 401b of the layer 401 of adhesive 400 that is substantially free of tackifier has penetrated through the first surface 212 of the second substrate 202, but has not reached or left the second surface 214 of the second substrate 202. Therefore, the first portion 401a of layer 401 of the substantially tack-free adhesive 400 does not completely penetrate through the thickness of the first substrate 200, and the second portion 401b of layer 401 of the substantially tack-free adhesive 400 does not completely penetrate through the thickness of the second substrate 202. (Continue to refer to...) Figure 11 The adhesive portion 403 further includes a central portion 401c of layer 401, wherein the layer 401 of adhesive 400, which is substantially free of tackifier, includes a central portion 401c extending between the first portion 401a and the second portion 401b. As shown, the second surface 208 of the first substrate 200 and the first surface 212 of the second substrate 202 are separated from each other by the central portion 401c of the layer 401 of adhesive 400, which is substantially free of tackifier.

[0085] It should be understood that Figure 11The illustrated bonding structure may include cross-sections with different zones, such as a first zone 401a, a second zone 401b, a central zone 401c, and a zone outside the surfaces of the substrates bonded together that is free of adhesive or polymer. In some configurations, the central zone 401c may have a solid thickness of a substantially tackifier-free adhesive, which may be void-free or cavity-free, or at least largely void-free or cavity-free. In some configurations where the first substrate 200 and / or the second substrate 202 comprises a nonwoven fabric, the substantially tackifier-free adhesive 400 may completely encapsulate at least one fiber deep within the nonwoven fabric. Bonding structures with this cross-section can help provide sufficient strength to withstand sustained peel forces generated by the fiber encapsulation and the cohesive strength of the solid central zone 401c. This configuration can be achieved by giving the layer 401 of the substantially tackifier-free adhesive 400 sufficient applied basis weight, and by applying compressive pressure to ensure that the substantially tackifier-free adhesive 400 penetrates the substrate sufficiently to encapsulate the fiber diameter. Compression pressure can also prevent adhesives 400, which contain virtually no tackifier, from completely penetrating through the substrate.

[0086] As previously described, the first substrate 200 may include a first nonwoven fabric 200' and / or the second substrate 202 may include a second nonwoven fabric 202', such as Figure 12 As shown, a portion of the adhesive portion 403 comprises an adhesive 400 that is substantially free of tackifiers and interwoven with the fibers of the first nonwoven fabric 200' and the second nonwoven fabric 202'. Figure 12 As shown, the first nonwoven fabric 200' may include first fibers 220, and the second nonwoven fabric includes second fibers 222. A first portion 401a of a layer 401 of a substantially tackifier-free adhesive 400 is interwoven with the first fibers 220 at a second surface 208 of the first nonwoven fabric 202', and a second portion 401b of a substantially tackifier-free adhesive layer 401 is interwoven with the second fibers 222 at a first surface 212 of the second nonwoven fabric 200'. Figure 12As shown, one or more first fibers 220 at and / or near the second surface 208 of the first nonwoven fabric 200' may include an outer periphery 221 completely surrounded by a substantially tack-free adhesive 400 of the first region 401a of layer 401. Similarly, one or more second fibers 222 at and / or near the first surface 212 of the second nonwoven fabric 202' may include an outer periphery 223 completely surrounded by a substantially tack-free adhesive 400 of the second region 401b of layer 401. It should be understood that the substantially tack-free adhesive 400 may completely surround the outer periphery 221 of additional first fibers 220 positioned away from the second surface 208 and further into the internal thickness of the first nonwoven fabric 200', and / or the substantially tack-free adhesive 400 may completely surround the outer periphery 223 of additional second fibers 222 positioned away from the first surface 212 and further into the internal thickness of the second nonwoven fabric 202'. It should be understood that the substantially tack-free adhesive 400 may partially surround the outer periphery 221 of the additional first fibers 220 located away from the second surface 208 and further into the inner thickness of the first nonwoven fabric 200', and / or the substantially tack-free adhesive 400 may partially surround the outer periphery 223 of the additional second fibers 222 located away from the first surface 212 and further into the inner thickness of the second nonwoven fabric 202'. For a further perspective view, Figure 13 A scanning electron microscope (“SEM” image of a cross-sectional view of an example adhesive portion 403 is shown, which includes a layer 401 of adhesive 400 that is substantially free of tackifier between a first nonwoven fabric 200' and a second nonwoven fabric 202'.

[0087] Continue to refer to Figure 12 The first fiber 220 may have a first diameter D1, and the second fiber 222 may have a second diameter D2. The first diameter D1 may be the same as or different from the second diameter D1. It should be understood that the central portion 401c of the layer 401 of the substantially tackifier-free adhesive 400 may have a thickness Tc. In some configurations, the thickness Tc is greater than the first diameter D1 and / or the second diameter D2. In some configurations, the thickness Tc may be greater than three times the first diameter D1 and / or three times the second diameter D2.

[0088] As described above, compression pressure can be used to prepare an adhesive structure between two nonwoven substrates comprising an adhesive 400 that is substantially free of tackifiers, in order to prevent the adhesive 400, which is substantially free of tackifiers, from completely penetrating through the nonwoven fabric. It should be understood that when producing such adhesive structures, it may be necessary to consider and / or control process conditions and material variables, such as the compressive force and properties of the substantially free of tackifiers adhesive, such as temperature and basis weight.

[0089] In some configurations, a substrate incorporating barrier properties can be used when creating the bonded portion. Such barrier properties can help reduce the need for precise control of process conditions and material properties during the formation of the bonded portion structure, while preventing complete permeation through the nonwoven fabric. Some nonwoven fabrics can be configured with a meltblown layer that provides such barrier properties. For example, some nonwoven fabric webs may include spunbond, meltblown, spunbond (“SMS”) fiber webs comprising an outer layer of spunbond thermoplastic (e.g., polyolefin) and an inner layer of meltblown thermoplastic. Such SMS nonwoven fabric webs may include a durable spunbond layer and an inner meltblown layer that is porous but inhibits the rapid permeation of fluids (e.g., bodily fluids) or bacteria through the fabric web. In some configurations, the meltblown layer may have fiber size and porosity that ensures the nonwoven fabric web’s permeability while inhibiting fluid permeation. In some configurations, the nonwoven component layers may include fine denier fibers (“N fibers”) having an average diameter of less than 1 micrometer (“N fiber layer”), which may be incorporated into or otherwise bonded to other nonwoven component layers to form a nonwoven material fiber web. For example, the N fiber layer may be used to produce SNS nonwoven fiber webs or SMNS nonwoven fiber webs. Thus, the nonwoven fiber web material may be an SMS material, comprising a spunbond layer, a meltblown layer, and any other combination of spunbond and meltblown layers, such as SMMS or SSMMS. Some examples may include one or more fiber layers (nanofibers and nanofiber layers) with a diameter of less than 1 micrometer; these examples include combinations of SMS, SMNS, SSMNS, or SMNMS nonwoven fiber webs (where “N” represents a nanofiber layer). Various examples of nonwovens, fiber compositions, the formation of fibers and nonwovens, and related methods are described in U.S. Patent Nos. 6,645,569, 6,863,933, 7,112,621, and 8,728,051, all of which are incorporated herein by reference.

[0090] Figure 14AThe resulting adhesive structure is shown, wherein a first substrate 200 includes a first nonwoven fabric 200' and / or a second substrate 202 includes a second nonwoven fabric 202', wherein the first nonwoven fabric 200' includes a first meltblown layer 224, as discussed above. Therefore, the first nonwoven fabric 200' may include a layered structure, wherein the first meltblown layer 224 is sandwiched between layers of the first fiber 220. A portion of the adhesive 403 includes an adhesive 400 that is substantially free of tackifiers, interwoven with the first fiber 220 of the first nonwoven fabric 200' and the second fiber 222 of the second nonwoven fabric 202'. A first portion 401a of a layer 401 of substantially tack-free adhesive 400 interweaves with first fibers 220 between the second surface 208 of the first nonwoven fabric 200' and the first meltblown layer 224, and a second portion 401b of a layer 401 of substantially tack-free adhesive 400 interweaves with second fibers 222 at the first surface 212 of the second nonwoven fabric 202'. As described above, one or more first fibers 220 at and / or near the second surface 208 of the first nonwoven fabric 200' may include an outer periphery 221 completely surrounded by the substantially tack-free adhesive 400 of the first region 401a of layer 401. And one or more second fibers 222 at and / or near the first surface 212 of the second nonwoven fabric 202' may include an outer periphery 223 completely surrounded by the substantially tack-free adhesive 400 of the second region 401b of layer 401. Figure 14A As shown, a first portion 401a of layer 401 of the substantially tackifier-free adhesive 400 can penetrate into the first nonwoven fabric 200' up to the first meltblown layer 224. The first meltblown layer 224 then acts as a barrier to help prevent the substantially tackifier-free adhesive 400 from completely penetrating through the first nonwoven fabric 200'.

[0091] Figure 14BAnother example of the formed adhesive structure is shown, wherein a first substrate 200 includes a first nonwoven fabric 200' and / or a second substrate 202 includes a second nonwoven fabric 202', wherein the first nonwoven fabric 200' includes a first meltblown layer 224, and wherein the second nonwoven fabric 202' includes a second meltblown layer 226. Therefore, the first nonwoven fabric 200' may include a layered structure, wherein the first meltblown layer 224 is sandwiched between layers of the first fiber 220, and the second nonwoven fabric 202' may include a layered structure, wherein the second meltblown layer 222 is sandwiched between layers of the second fiber 222. A first portion 401a of layer 401 of the substantially tack-free adhesive 400 is interwoven with first fibers 220 between the second surface 208 of the first nonwoven fabric 200' and the first meltblown layer 224, and a second portion 401b of layer 401 of the substantially tack-free adhesive 400 is interwoven with second fibers 222 between the first surface 212 of the second nonwoven fabric 202' and the second meltblown layer 226. As... Figure 14B As shown, a first portion 401a of layer 401 of the substantially tack-free adhesive 400 can penetrate into the first nonwoven fabric 200' up to the first meltblown layer 224, and a second portion 401b of layer 401 of the substantially tack-free adhesive 400 can penetrate into the second nonwoven fabric 202' up to the second meltblown layer 226. The first meltblown layer 224 and the second meltblown layer 226 then act as barriers to help prevent the substantially tack-free adhesive 400 from completely penetrating through the first nonwoven fabric 200' and the second nonwoven fabric 202'.

[0092] Therefore, nonwovens with meltblown layers (such as the various fiber web structures discussed above) can help ensure that a sufficient amount of substantially tackifier-free adhesive 400 and high compression can be used to form the bonded structure, while helping to reduce the risk of the substantially tackifier-free adhesive 400 completely penetrating through the nonwoven fabric. It should also be understood that other types of fiber web structures can be used to help achieve similar results, such as laminate structures including membranes, localized coatings, etc.

[0093] Now for reference Figure 3 and Figure 4 It should be understood that the adhesive applicator 302 may be configured to apply a layer 401 of adhesive 400, which is substantially free of tackifiers, in various ways. For example, the adhesive applicator may be configured as a slot coat applicator or a melt-blown applicator. In some configurations, the substantially tackifier-free adhesive 400 may be heated before reaching the adhesive applicator 302 and / or may be heated as it flows through the adhesive applicator 302. The device 300 herein may also include one or more cooling devices 328, which in Figure 4The area represented by the dashed rectangle is suitable for removing heat energy from the first region 404 and / or the second region 406 of the adhesion region 402. It should be understood that such a cooling device 328 can be constructed in various ways. In some configurations, the cooling device 328 may include a heat exchanger, such as a radiator. For example, the device 300 may be configured to advance a laminate 204 into a cooling device 328 configured as one or more cooling rollers, wherein the laminate 204 may partially enclose the cooling surface of the cooling rollers. In some configurations, the cooling device 328 may include a device such as a fan or blower that moves air or other gas along the second surface 214 of the second substrate 202 and / or the first surface 206 of the first substrate 200 and the first surface 212 of the second substrate 202 to remove heat energy from the adhesion region 402 by utilizing convection. Although Figure 4 The cooling device 328 is schematically shown adjacent to the second surface 214 of the second substrate 202. However, it should be understood that the cooling device 328 may be configured to have components that are in close proximity to or in contact with the first surface 212 and / or the second surface 214 of the second substrate 202 and / or the first surface 206 of the first substrate 200.

[0094] As previously mentioned, the apparatus and methods described herein can also be used to bond substrates constructed as continuous substrates. For example, Figure 6 A schematic diagram of an example configuration of device 300 is shown, which can bond a continuous first substrate 201 and a continuous second substrate 202 to form a laminate 204 using an adhesive 400 that is substantially free of tackifiers. Device 300 may include a conveying assembly 304, as described above, to transport the first substrate 201 from a first position P1 to a second position P2 in the machine direction MD. Figure 6 As shown, a continuous first substrate 201 is advanced along the machine direction MD onto the transfer assembly 304. The first surface 206 of the advanced continuous first substrate 201 engages with the moving carrier surface 306 at the pick-up area 312. (Continuing to refer to...) Figure 6 The conveying assembly 304 rotates about the first axis 308, causing the carrier surface 306 and the continuous first substrate 201 positioned on the carrier surface 306 to move from the first position P1 to the second position P2 about the first axis 308. Then, at the drop zone 316, the continuous first substrate 201 is conveyed to the continuous second substrate 202 to form the laminate 204.

[0095] For details, please refer to the following: Figure 6 and Figure 7AA continuous second substrate 202 is advanced in the machine direction MD past the adhesive applicator 302 and toward the discharge area 316. The adhesive applicator 302 deposits a layer 401 of adhesive 400, which is substantially free of tackifier, onto the first surface 212 of the second substrate 202 to define the adhesion area 402 of the second substrate 202. At the discharge area 316, the continuous first substrate 201 is conveyed from the conveying assembly 304 to position the second surface 208 of the continuous first substrate 201 onto the adhesion area 402.

[0096] like Figure 6 and Figure 7A As shown, the adhesion region 402 of the laminate 204 may include a first region 404 and a second region 406. A substantially tackifier-free adhesive 400 is positioned in the first region 404 of the adhesion region 402 between the second surface 208 of the continuous first substrate 201 and the first surface 212 of the continuous second substrate 202. And a substantially tackifier-free adhesive 400 is not positioned in the second region 406 of the adhesion region 402 between the second surface 208 of the continuous first substrate 201 and the first surface 212 of the continuous second substrate 202. As described above, it should be understood that the adhesion region 402 and the continuous first substrate 201 may have various shapes. For example, although the adhesion region 402 is generally depicted herein as defining a continuous rectangular shape on the first surface 212 of the second substrate 202, it should be understood that the adhesion region 402 may have edges defining circles, squares, ovals, ellipses, and various other types of shapes, which may or may not correspond to the shape defined wholly or partially by the edges of the continuous first substrate 201. It should be understood that the adhesion region 402 and the continuous first substrate 201 may have edges of the same shape or may have different shapes.

[0097] It should also be understood that the continuous first substrate 201 may be oriented relative to the second substrate 202 and / or the adhesion region 402 in various ways. For example, as Figure 7B As shown, a continuous first substrate 201 may be oriented on a second substrate 202 such that a portion of the second surface 208 of the first substrate 201 may not be fully positioned on the first surface 212 and / or adhesion region 402 of the second substrate 202. Furthermore, it should be understood that the device 300 may be configured to assemble a laminate 204 having a plurality of continuous first substrates 201 and / or continuous second substrates 202 in various orientations. For example, as... Figure 7BAs shown, the laminate 204 may include consecutive first substrates 201a and 201b, which are respectively disposed along the machine direction MD on a first edge 216 and a second edge 218 of a second substrate 202 and a corresponding adhesion region 402. As previously described, the adhesive applicator 302 may be configured to apply an adhesive 400, which is substantially free of tackifier, to either or both of the consecutive first substrates 201 and the consecutive second substrates 202. It should also be understood that... Figures 7A to 7B The arrangement shown can be configured such that a substantially tack-free adhesive 400 can be completely covered by a continuous first substrate 201 and second substrate 202, and therefore, the adhesion region 402 may not include the second region 406. It should also be understood that the substantially tack-free adhesive 400 in the adhesion region 402 can be applied to define various bond structures, such as those referenced below. Figure 11 and Figure 12 The subject of discussion.

[0098] As described above, the laminate 204 discussed herein can be used to construct various components for manufacturing different types of absorbent articles. For example, see reference... Figure 1A , Figure 1B and Figures 2A to 2C The laminate 204 described herein can be used to form all or part of components, such as: base structure 102; side panels 104, 106, 108, 110; belts 172, 174; bottom panel 136; top panel 138; absorbent assembly 140; leg clamps 156; waist belt 158; side wings 160; fastening members 162, 164; and / or connecting areas 168. For example, see reference. Figure 5A As disclosed herein, a delivery assembly 304 having a carrier surface 306 can be used to apply a first substrate 200 in the form of a belt 158 ​​to a second substrate 202 in the form of a pushing top substrate 138. In another example, refer to Figure 5B As disclosed herein, a transfer assembly 304 having a carrier surface 306 can be used to apply first substrates 200a, 200b in the form of side sheets 104, 106, 108, 110 to a second substrate 202 in the form of a advancing top sheet substrate 138 and / or an advancing bottom sheet substrate 136. In another example, refer to Figure 5C As disclosed herein, a transport assembly 304 having a carrier surface 306 can be used to apply a first substrate 200 in the form of a base structure 102 to a second substrate 202a, 202b in the form of a first belt 172 and a second belt 174. In another example, refer to Figure 7A As disclosed herein, a transfer assembly 304 having a carrier surface 306 can be used to apply a continuous first substrate 201 in the form of a top film substrate 138 to a second substrate 202 in the form of a advancing film substrate 136. In another example, refer to Figure 7B As disclosed herein, a transfer assembly 304 having a carrier surface 306 can be used to apply a continuous first substrate 201 in the form of a leg clamp 156 to a second substrate 202 in the form of a propulsive top plate substrate 138.

[0099] In another example, the method described herein can be used to assemble laminate 204 to form side seams 184, 186 on diaper pants 100P, as described in the references above. Figures 2A to 2C As described above. For example, see the following references. Figures 8 to 10 The adhesive 400, which is substantially free of tackifiers, can be used to connect the opposite end regions of the first elastic band 172 to the opposite end regions of the second elastic band 174 at the first side joint 184 and the second side joint 186, thereby defining the annular elastic band 170 and the waist opening 176 and the leg opening 178.

[0100] like Figure 8 As shown, when assembling the diaper pants 100P, the first base 201 can be in the form of a first elastic band laminate 172a, and the second base 202 can be in the form of a second elastic band laminate 174a. The first elastic band laminate 172a and the second elastic band laminate 174a can be separated from each other in the transverse direction CD, and can be connected to each other using a plurality of base structures 102 intermittently spaced along the machine direction MD. Furthermore... Figure 8 As shown, a layer 401 of adhesive 400, which is substantially free of tackifiers, can be applied to the second surface 208 of the first substrate 202 to define an adhesion region 402. The adhesion region 402 may be in the form of discrete regions located between adjacent base structures 102. In some configurations, the adhesion region 402 may extend continuously along the machine direction MD.

[0101] Continue to refer to Figure 8During subsequent assembly operations, the base structure 102 can be folded (indicated by the dashed arrow "A") to position the second surface 208 of the first substrate 201 facing the first surface 212 of the second substrate 202. Pressure can also be applied to the first substrate 201 and the second substrate 202 in the adhesion region 402 to help the substantially tackifier-free adhesive 400 penetrate into the first substrate 201 and the second substrate 202 and / or bond the first substrate and the second substrate together to form a laminate 204. Subsequently, discrete diaper pants 100P can be formed by separating the first substrate 201 and the second substrate 202 into a first strip 172 and a second strip 174 by cutting through the adhesion region 402 along the transverse direction CD. Thus, the adhesion region 402 can be divided to define a first adhesion region 402a and a second adhesion region 402b that correspond to the first side seam 184 and the second side seam 186, respectively. It should be understood that, instead of the adhesion regions 402 that are subsequently divided into first adhesion regions 402a and second adhesion regions 402b, a layer 401 of adhesive 400 that is substantially free of tackifier may be applied to define discrete first adhesion regions 402a and second adhesion regions 402b, such as, for example Figure 8A As shown. Therefore, the first substrate 201 and the second substrate 202 are cut along the transverse CD between the first adhesion region 402a and the second adhesion region 402b. It should also be understood that an adhesive 400 that is substantially free of tackifiers may be applied to either or both of the first substrate 201 and the second substrate 202.

[0102] Now for reference Figure 8 , Figure 9 and Figure 10 At the side seams 184 and 186, the first substrate 201 can be bonded to the second substrate 202 to define a first region 404 and a second region 406 of the adhesion regions 402a and 402b. Figure 9 and Figure 10 A detailed view of the first side 184 is shown, which can be a mirror image of the second side seam 186. (See attached image.) Figure 9 and 10As shown, in the first region 404 of the adhesion area 402a, a substantially tackifier-free adhesive 400 is positioned between the second surface 208 of the first substrate 201 and the first surface 212 of the second substrate 202, bonding them together. And in the second region 406 of the adhesion area 402, a substantially tackifier-free adhesive 400 is positioned between the second surface 208 of the first substrate 201 and the first surface 212 of the second substrate 202, but does not bond them together. During subsequent processing operations such as folding and packaging, the substantially tackifier-free adhesive 400 in the second region 406 will not bond to other parts of the diaper trousers 100P. Furthermore, during use of the article, the substantially tackifier-free adhesive 400 in the second region 406 can be exposed to the wearer's skin and / or clothing without accidentally adhering to the wearer's skin and / or clothing.

[0103] It should be understood that Figure 9 and Figure 10 The arrangement shown can be configured such that the adhesive 400, which is substantially free of tackifiers, can be completely covered by the first substrate 201 and the second substrate 202, and therefore, the adhesion area 402 may not include the second region 406. It should also be understood that the side seams 184, 186 can be configured to have an adhesive structure, as referenced above. Figure 11 and Figure 12 The subject of discussion.

[0104] It should be understood that side seams can be formed using the methods and apparatus described herein with adhesives that are substantially free of tackifiers, and can also be formed in conjunction with mechanical bonding processes. It should also be understood that the methods and apparatus described herein are adaptable to operation with various types of absorbent article assembly processes, such as those disclosed, for example, in U.S. Patent Nos. 8,186,296, 9,265,672, 9,248,054, and 9,730,839, and U.S. Patent Publications 2013 / 0255861 A1, 2013 / 0255862 A1, 2013 / 0255863 A1, 2013 / 0255864 A1, and 2013 / 0255865 A1, all of which are incorporated herein by reference.

[0105] combination

[0106] A1. A method of bonding a substrate, the method comprising: providing a first substrate including a first surface and an opposing second surface; providing a second substrate including a first surface and an opposing second surface; applying a layer of a substantially tackifier-free adhesive to the first surface of the second substrate to define an adhesion region; positioning the second surface of the first substrate on the adhesion region of the second substrate; and pressing the first substrate and the second substrate together in the adhesion region such that a first portion of the substantially tackifier-free adhesive layer enters the first substrate and a second portion of the substantially tackifier-free adhesive layer enters the second substrate, wherein the first portion of the substantially tackifier-free adhesive layer penetrates through the second surface of the first substrate, wherein the second portion of the substantially tackifier-free adhesive layer penetrates through the first surface of the second substrate, and the second surface of the first substrate and the first surface of the second substrate are separated from each other by a central portion of the substantially tackifier-free adhesive layer.

[0107] A2. The method according to paragraph A1, wherein a first portion of the adhesive, which is substantially free of tackifier, penetrates through a first substrate without reaching and penetrating through a first surface of the first substrate, and wherein a second portion of the adhesive, which is substantially free of tackifier, penetrates through a second substrate without reaching and penetrating through a second surface of the second substrate.

[0108] A3. The method according to paragraph A1 or A2, wherein the first substrate comprises a first nonwoven fabric and the second substrate comprises a second nonwoven fabric.

[0109] A4. The method according to paragraph A3, wherein the first nonwoven fabric comprises a first fiber, and wherein the second nonwoven fabric comprises a second fiber, and wherein a first portion of an adhesive substantially free of tackifier is interwoven with the first fiber on a second surface of the first nonwoven fabric, and a second portion of an adhesive substantially free of tackifier is interwoven with the second fiber on a first surface of the second nonwoven fabric.

[0110] A5. The method according to paragraph A4, wherein the first fiber has a first diameter, and wherein the second fiber has a second diameter, and wherein the central portion of the adhesive layer, which is substantially free of tackifier, has a thickness, wherein the thickness is greater than 1 times the first diameter and 1 times the second diameter.

[0111] A6. According to the method described in paragraph A4, the first diameter is different from the second diameter.

[0112] A7. The method according to any one of paragraphs A1 to A6, wherein at least one of the first nonwoven fabric and the second nonwoven fabric comprises a meltblown layer.

[0113] A8. The method according to any one of paragraphs A1 to A7, wherein the adhesive, which is substantially free of tackifier, comprises an adhesive composition comprising a polymer and / or copolymer, wherein the adhesive composition comprises less than 10% by weight of tackifier.

[0114] A9. The method according to any one of paragraphs A1 to A8, wherein the adhesive composition contains no or lacks a tackifier.

[0115] A10. The method according to any one of paragraphs A1 to A9, wherein providing the first substrate further includes cutting discrete pieces from the continuous first substrate.

[0116] A11. The method according to any one of paragraphs A1 to A10, wherein providing the second substrate further includes advancing a continuous second substrate in the machine direction.

[0117] A12. The method according to any one of paragraphs A1 to A11, the method further comprising a component for converting the first substrate and the second substrate into an absorbent article.

[0118] A13. The method according to any one of paragraphs A1 to A12, wherein the first base comprises one of a waist belt, a connecting area, a leg cuff, an absorbent base structure, and a first elastic band, and wherein the second base comprises one of a top sheet, a bottom sheet, and a second elastic band.

[0119] B1. An absorbent article comprising: a laminate comprising: a first nonwoven fabric including a first surface and an opposing second surface; a second nonwoven fabric including a first surface and an opposing second surface; wherein the first nonwoven fabric is bonded to the second nonwoven fabric in an adhesion region, wherein the adhesion region includes a layer of a substantially tackifier-free adhesive positioned between the first and second nonwoven fabrics; wherein a first portion of the substantially tackifier-free adhesive layer permeates the second surface of the first nonwoven fabric; wherein a second portion of the substantially tackifier-free adhesive layer permeates the first surface of the second nonwoven fabric; and wherein in the adhesion region, the second surface of the first nonwoven fabric is separated from the first surface of the second nonwoven fabric by a central portion of the substantially tackifier-free adhesive layer; and wherein the first portion of the substantially tackifier-free adhesive interweaves with fibers between the first and second surfaces of the second nonwoven fabric in a first region of the adhesion region, and also interweaves with fibers between the first and second surfaces of the first nonwoven fabric.

[0120] B2. The absorbent article according to paragraph B1, wherein a first portion of the adhesive, which is substantially free of tackifier, penetrates into a first nonwoven fabric without reaching a first surface of the first nonwoven fabric, and wherein a second portion of the adhesive, which is substantially free of tackifier, penetrates into a second nonwoven fabric without reaching a second surface of the second nonwoven fabric.

[0121] B3. The absorbent article according to paragraph B2, wherein the first nonwoven fabric comprises a first fiber, and wherein the second nonwoven fabric comprises a second fiber, and wherein a first portion of an adhesive substantially free of tackifier is interwoven with the first fiber on a second surface of the first nonwoven fabric, and a second portion of an adhesive substantially free of tackifier is interwoven with the second fiber on a first surface of the second nonwoven fabric.

[0122] B4. The absorbent article according to paragraph B3, wherein the first fiber has a first diameter, and wherein the second fiber has a second diameter, and wherein the central portion of the adhesive layer, which is substantially free of tackifier, has a thickness, wherein the thickness is greater than 1 times the first diameter and 1 times the second diameter.

[0123] B5. The absorbent article according to claim B4, wherein the first diameter is different from the second diameter.

[0124] B6. The absorbent article according to any one of paragraphs B1 to B5, wherein the adhesive, which is substantially free of tackifier, comprises an adhesive composition comprising a polymer and / or copolymer, wherein the adhesive composition comprises less than 10% by weight of tackifier.

[0125] B7. The absorbent article according to any one of paragraphs B1 to B6, wherein the adhesive composition contains no or lacks a tackifier.

[0126] B8. The absorbent article according to any one of paragraphs B1 to B7, wherein the first nonwoven fabric comprises one of a waistband, a connecting area, leg cuffs, an absorbent base structure, and a first elastic band, and wherein the second nonwoven fabric comprises one of a top sheet, a bottom sheet, and a second elastic band.

[0127] B9. The absorbent article according to any one of paragraphs B1 to B8, wherein the first nonwoven fabric includes a first elastic band, and the second nonwoven fabric includes a second elastic band, and wherein the adhesive area defines a side seam.

[0128] B10. The absorbent article according to any one of paragraphs B1 to B9, wherein at least one of the first nonwoven fabric and the second nonwoven fabric comprises a meltblown layer.

[0129] Bio-based content of components

[0130] Components of the absorbent articles described herein may be at least partially composed of a bio-based content, as described in U.S. Patent Application No. 2007 / 0219521 A1, which is incorporated herein by reference. For example, superabsorbent polymer components may be bio-based rather than derived from bio-based acrylic acid. Bio-based acrylic acid and methods for its production are further described in U.S. Patent Application Publication No. 2007 / 0219521 and U.S. Patent Nos. 8,703,450, 9,630,901, and 9,822,197, all of which are incorporated herein by reference. Other components, such as nonwoven and membrane components, may comprise bio-based polyolefin materials. Bio-based polyolefins are further discussed in U.S. Patent Application Publications Nos. 2011 / 0139657, 2011 / 0139658, 2011 / 0152812, and 2016 / 0206774 and U.S. Patent No. 9,169,366, all of which are incorporated herein by reference. Example bio-based polyolefins used in this disclosure include those with the name SHA7260. ™ SHE150 ™ Or SGM9450F ™ The obtained polymers (all available from Braskem SA).

[0131] Absorbent article components may include, for example, bio-based content values ​​of about 10% to about 100%, about 25% to about 100%, about 40% to about 100%, about 50% to about 100%, about 75% to about 100%, or about 90% to about 100%, as measured using ASTM D6866-10 Method B.

[0132] Recycling-friendly and bio-based absorbent products

[0133] Components of the absorbent articles described herein can be recycled for other uses, regardless of whether they are (at least partially) formed from recyclable materials. Examples of recyclable absorbent article materials are nonwovens, membranes, fluff pulp, and superabsorbent polymers. The recycling process may involve sterilizing the absorbent articles using an autoclave, after which the absorbent articles can be shredded and separated into different byproduct streams. Example byproduct streams may include plastics, superabsorbent polymers, and cellulosic fibers, such as pulp. These byproduct streams can be used to produce fertilizers, manufacture plastic articles, paper products, adhesives, building materials, absorbent pads for pet or hospital beds, and / or for other uses. Further details regarding absorbent articles that facilitate recycling, the design of recycling-friendly diapers, and the design of recycling-friendly and bio-based component diapers are disclosed in U.S. Patent Application Publication No. 2019 / 0192723, which is incorporated herein by reference.

[0134] The dimensions and values ​​disclosed herein should not be construed as strictly limited to the precise numerical values ​​cited. Rather, unless otherwise specified, each such dimension is intended to represent the stated value and the range surrounding its functional equivalent. For example, a dimension disclosed as “40 mm” is intended to represent “approximately 40 mm”.

[0135] Unless expressly excluded or otherwise limited, every reference cited herein, including any cross-references or related patents or patent applications, and any patent application or patent claiming priority to or benefiting from it, is incorporated herein by reference in its entirety. Reference to any reference is not an endorsement of it as prior art to any disclosed or protected art herein, nor is it an endorsement of any such invention, either on its own or in combination with any one or more references. Furthermore, where any meaning or definition of a term in this invention conflicts with any meaning or definition of the same term in referenced documents, the meaning or definition given to that term in this invention shall prevail.

[0136] While specific embodiments of the invention have been illustrated and described by way of example, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, it is intended that all such changes and modifications falling within the scope of the invention be covered by the appended claims.

Claims

1. A method for bonding a substrate, the method comprising: A first substrate (200) is provided, the first substrate including a first surface (206) and an opposing second surface (208); A second substrate (202) is provided, the second substrate including a first surface (212) and an opposing second surface (214); A layer (401) of an adhesive (400) that is substantially free of tackifiers is applied to the first surface (212) of the second substrate (202) to define the adhesion area (402). Position the second surface (208) of the first substrate (200) on the adhesion region (402) of the second substrate (202); as well as In the adhesion area (402), the first substrate (200) and the second substrate (202) are pressed together such that a first portion (401a) of the layer (401) of the substantially tack-free adhesive (400) enters the first substrate (200), and a second portion (401b) of the layer (401) of the substantially tack-free adhesive (400) enters the second substrate (202), wherein the first portion (401a) of the layer (401) of the substantially tack-free adhesive (400)... a) Penetrates through the second surface (208) of the first substrate (200), wherein the second portion (401b) of the layer (401) of the substantially tack-free adhesive (400) penetrates through the first surface (212) of the second substrate (202), and the second surface (208) of the first substrate (200) and the first surface (212) of the second substrate (202) are separated from each other by the central portion (401c) of the layer (401) of the substantially tack-free adhesive (400).

2. The method of claim 1, wherein the first portion (401a) of the substantially tack-free adhesive (400) penetrates through the first substrate (200) without reaching and penetrating through the first surface (206) of the first substrate (200), and wherein the second portion (401b) of the substantially tack-free adhesive (400) penetrates through the second substrate (202) without reaching and penetrating through the second surface (214) of the second substrate (202).

3. The method according to claim 1 or 2, wherein the first substrate (200) comprises a first nonwoven fabric (200') and the second substrate (202) comprises a second nonwoven fabric (202').

4. The method of claim 3, wherein the first nonwoven fabric (200') comprises a first fiber (220), and wherein the second nonwoven fabric (202') comprises a second fiber (222), and wherein the first portion (401a) of the substantially tackifier-free adhesive (400) is interwoven with the first fiber (220) on the second surface (208) of the first nonwoven fabric (202), and the second portion (401b) of the substantially tackifier-free adhesive (400) is interwoven with the second fiber (222) on the first surface (212) of the second nonwoven fabric (200').

5. The method according to claim 4, wherein the first fiber (220) has a first diameter, and wherein the second fiber (222) has a second diameter, and wherein the central portion (401c) of the layer (401) of the substantially tackifier-free adhesive (400) has a thickness, wherein the thickness is greater than 1 times the first diameter and 1 times the second diameter.

6. The method according to claim 4 or 5, wherein the first diameter is different from the second diameter.

7. The method according to any one of claims 3 to 6, wherein at least one of the first nonwoven fabric (200') and the second nonwoven fabric (202') comprises a meltblown layer.

8. The method according to any one of claims 1 to 7, wherein the substantially tackifier-free adhesive (400) comprises an adhesive composition comprising a polymer and / or copolymer, wherein the adhesive composition comprises less than 10% by weight of a tackifier.

9. The method of claim 8, wherein the adhesive composition contains no or lacks a tackifier.

10. The method according to any one of claims 1 to 9, wherein providing the first substrate (200) further includes cutting discrete pieces from a continuous first substrate.

11. The method of claim 10, wherein providing the second substrate (202) further comprises advancing a continuous second substrate in the machine direction.

12. The method according to any one of claims 1 to 11, the method further comprising a component for converting the first substrate (200) and the second substrate (202) into an absorbent article (100).

13. The method according to claim 12, wherein the first base (200) comprises one of a waist belt (156), a connecting area (168), a leg cuff (158), an absorbent base structure (102), and a first elastic band (172), and wherein the second base (202) comprises one of a top sheet (138), a bottom sheet (136), and a second elastic band (174).

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