Methods and apparatuses for making elastomeric laminates

The present disclosure relates to methods for making elastomeric laminates that may be used as components of absorbent articles. Aspects of the methods for assembling elastomeric laminates may utilize elastic strands supplied from beams that may be joined with first and second substrates, and may be configured to carry out various types of operations, such as bonding and splicing operations.

FIELD OF THE INVENTION

The present disclosure relates to methods for manufacturing absorbent articles, and more particularly, to apparatuses and methods for making elastomeric laminates that may be used as components of absorbent articles.

BACKGROUND OF THE INVENTION

Along an assembly line, various types of articles, such as for example, diapers and other absorbent articles, may be assembled by adding components to and/or otherwise modifying an advancing, continuous web of material. For example, in some processes, advancing webs of material are combined with other advancing webs of material. In other examples, individual components created from advancing webs of material are combined with advancing webs of material, which in turn, are then combined with other advancing webs of material. In some cases, individual components created from an advancing web or webs are combined with other individual components created from other advancing webs. Webs of material and component parts used to manufacture diapers may include: backsheets, topsheets, leg cuffs, waist bands, absorbent core components, front and/or back ears, fastening components, and various types of elastic webs and components such as leg elastics, barrier leg cuff elastics, stretch side panels, and waist elastics. Once the desired component parts are assembled, the advancing web(s) and component parts are subjected to a final knife cut to separate the web(s) into discrete diapers or other absorbent articles.

Some absorbent articles have components that include elastomeric laminates. Such elastomeric laminates may include an elastic material bonded to one or more nonwovens. The elastic material may include an elastic film and/or elastic strands. In some laminates, a plurality of elastic strands are joined to a nonwoven while the plurality of strands are in a stretched condition so that when the elastic strands relax, the nonwoven gathers between the locations where the nonwoven is bonded to the elastic strands, and in turn, forms corrugations. The resulting elastomeric laminate is stretchable to the extent that the corrugations allow the elastic strands to elongate.

In some assembly processes, stretched elastic strands may be advanced in a machine direction and may be adhered between two advancing substrates, wherein the stretched elastic strands are spaced apart from each other in a cross direction. Some assembly processes are also configured with several elastic strands that are very closely spaced apart from each other in the cross direction. In some configurations, close cross directional spacing between elastic strands can be achieved by drawing elastic strands from windings that have been stacked in the cross direction on a beam. For example, various textile manufacturers may utilize beam elastics and associated handling equipment, such as available from Karl Mayer Corporation.

However, problems can be encountered in manufacturing processes when drawing elastic strands stacked on a beam. For example, relatively low decitex elastic strands supplied on a beam may include a coating, sometimes referred to a yarn finish or spin finish, to help prevent the elastics strands from adhering to themselves, each other, and/or downstream handling equipment. When constructing absorbent articles, hot melt adhesives are sometimes used to adhere stretched elastic stands to advancing substrates to create elastic laminates. However, hot melt adhesives used to adhere stretched elastic strands to substrates when constructing absorbent articles may not adhere well to strands having a spin finish. As such, increased amounts of adhesive may be required to adequately adhere the stretched elastic strands to the substrates than would otherwise be required for elastic stands without a spin finish. In turn, relatively larger amounts of adhesives required to bond the elastic strands to the substrates may have a negative impact on aspects of the resulting product, such as with respect to costs, functionality, and aesthetics.

In an attempt to overcome the aforementioned problems associated with adhesives, some assembly processes may be configured to apply mechanical bonds with heat and pressure to trap the stretched elastic strands between two substrates. Such mechanical bonds may be created, for example, by advancing the substrates and elastic strands between an ultrasonic horn and anvil. However, the heat and pressure from the anvil and horn may also sever the elastic strands. In some instances, the runout of the anvil can cause variations in the distance between the ultrasonic horn and anvil during the bonding process. Such distance variations can cause the elastic strands to be severed during the bonding process and/or result in relatively inconsistent bond quality. It may be possible to mitigate problems associated with severing the elastic strands by operating at relatively slow speeds. For example, at relatively slow advancement speeds, relatively less pressure may be exerted on the elastic strands during the bonding process. In addition, the ultrasonic horn may be configured to move toward and away from the anvil during the bonding process in order to compensate for relatively large runout values on the anvil. However, disposable absorbent article manufacturing lines may operate at relatively high speeds. As such, it can be inefficient and/or cost prohibitive to reduce the advancement speeds in high speed manufacturing operations to achieve the desired bond qualities without severing the elastic strands. In addition, ultrasonic horns may not be able to compensate for relatively high anvil runout values at high speeds. In some configurations, grooves may be provided in the horn or anvil for the elastic strands to nest in and to shield the elastic strands from pressure and prevent severing through the bonding process, such as disclosed in U.S. Pat. No. 6,291,039 and European Patent Publication No. EP 3 092 997 B1. However, positioning hundreds of elastic strands drawn from a beam in nesting grooves on an ultrasonic horn and/or anvil may add complexity to the assembly process.

Consequently, it would be beneficial to provide methods and apparatuses for producing elastomeric laminates at relatively high advancement speeds by mechanically bonding elastic strands between substrates without severing the elastics strands, and/or without the need for having to guide elastic strands into designated nesting grooves in a mechanical bonding device.

SUMMARY OF THE INVENTION

In one aspect, a method for making absorbent articles comprises steps of: rotating a pattern roll about an axis of rotation extending axially in a cross direction, the pattern roll comprising bonding surfaces extending radially outward from the axis of rotation; providing a pressing surface adjacent the pattern roll to define a nip between the pattern roll and the pressing surface; advancing a first substrate and a second substrate through in a machine direction through the nip at a first speed S1 of at least about 100 meters per minute; providing elastic strands wound onto a beam; rotating the beam to unwind the elastic strands from the beam; advancing the elastic strands from the rotating beam; stretching the elastic strands; and bonding the stretched elastic strands between the first substrate and the second substrate at the nip to form an elastomeric laminate.

In another aspect, a method for making absorbent articles comprises steps of: rotating a pattern roll about an axis of rotation extending axially in a cross direction, the pattern roll comprising bonding surfaces extending radially outward from the axis of rotation; providing an ultrasonic horn comprising an energy transfer surface to define a nip between the pattern roll and the energy transfer surface; advancing a first substrate and a second substrate through in a machine direction through the nip at a first speed S1 of at least about 100 meters per minute; providing elastic strands wound onto a beam; rotating the beam to unwind the elastic strands from the beam; advancing the elastic strands from the rotating beam; stretching the elastic strands; and bonding the stretched elastic strands between the first substrate and the second substrate at the nip to form an elastomeric laminate.

In yet another aspect, a method for making absorbent articles comprises steps of: rotating a pattern roll about an axis of rotation extending axially in a cross direction, the pattern roll comprising bonding surfaces extending radially outward from the axis of rotation; providing an ultrasonic horn comprising an energy transfer surface to define a nip between the pattern roll and the energy transfer surface; advancing a first substrate and a second substrate through in a machine direction through the nip at a first speed S1 of at least about 100 meters per minute; providing elastic strands wound onto a beam; rotating the beam to unwind the elastic strands from the beam; advancing the elastic strands from the rotating beam; stretching the elastic strands; positioning the stretched elastic strands between the first substrate and the second substrate; and welding the first substrate and the second substrate together at the nip to form an elastomeric laminate.

DETAILED DESCRIPTION OF THE INVENTION

The following term explanations may be useful in understanding the present disclosure:

“Absorbent article” is used herein to refer to consumer products whose primary function is to absorb and retain soils and wastes. Absorbent articles can comprise sanitary napkins, tampons, panty liners, interlabial devices, wound dressings, wipes, disposable diapers including taped diapers and diaper pants, inserts for diapers with a reusable outer cover, adult incontinent diapers, adult incontinent pads, and adult incontinent pants. The term “disposable” is used herein to describe absorbent articles which generally are not intended to be laundered or otherwise restored or reused as an absorbent article (e.g., they are intended to be discarded after a single use and may also be configured to be recycled, composted or otherwise disposed of in an environmentally compatible manner).

An “elastic,” “elastomer” or “elastomeric” refers to materials exhibiting elastic properties, which include any material that upon application of a force to its relaxed, initial length can stretch or elongate to an elongated length more than 10% greater than its initial length and will substantially recover back to about its initial length upon release of the applied force.

As used herein, the term “joined” encompasses configurations whereby an element is directly secured to another element by affixing the element directly to the other element, and configurations whereby an element is indirectly secured to another element by affixing the element to intermediate member(s) which in turn are affixed to the other element.

The term “substrate” is used herein to describe a material which is primarily two-dimensional (i.e. in an XY plane) and whose thickness (in a Z direction) is relatively small (i.e. 1/10 or less) in comparison to its length (in an X direction) and width (in a Y direction). Non-limiting examples of substrates include a web, layer or layers or fibrous materials, nonwovens, films and foils such as polymeric films or metallic foils. These materials may be used alone or may comprise two or more layers laminated together. As such, a web is a substrate.

The term “nonwoven” refers herein to a material made from continuous (long) filaments (fibers) and/or discontinuous (short) filaments (fibers) by processes such as spunbonding, meltblowing, carding, and the like. Nonwovens do not have a woven or knitted filament pattern.

The term “machine direction” (MD) is used herein to refer to the direction of material flow through a process. In addition, relative placement and movement of material can be described as flowing in the machine direction through a process from upstream in the process to downstream in the process.

The term “cross direction” (CD) is used herein to refer to a direction that is generally perpendicular to the machine direction.

The term “taped diaper” (also referred to as “open diaper”) refers to disposable absorbent articles having an initial front waist region and an initial back waist region that are not fastened, pre-fastened, or connected to each other as packaged, prior to being applied to the wearer. A taped diaper may be folded about the lateral centerline with the interior of one waist region in surface to surface contact with the interior of the opposing waist region without fastening or joining the waist regions together. Example taped diapers are disclosed in various suitable configurations U.S. Pat. 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 Publication Nos. 2013/0072887 A1; 2013/0211356 A1; and 2013/0306226 A1, all of which are incorporated by reference herein.

The term “pant” (also referred to as “training pant”, “pre-closed diaper”, “diaper pant”, “pant diaper”, and “pull-on diaper”) refers herein to disposable absorbent articles having a continuous perimeter waist opening and continuous perimeter leg openings designed for infant or adult wearers. A pant can be configured with a continuous or closed waist opening and at least one continuous, closed, leg opening prior to the article being applied to the wearer. A pant can be preformed or pre-fastened by various techniques including, but not limited to, joining together portions of the article using any refastenable and/or permanent closure member (e.g., seams, heat bonds, pressure welds, adhesives, cohesive bonds, mechanical fasteners, etc.). A pant can be preformed anywhere along the circumference of the article in the waist region (e.g., side fastened or seamed, front waist fastened or seamed, rear waist fastened or seamed). Example diaper pants in various configurations are disclosed in U.S. Pat. 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 Publication 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 A1, all of which are incorporated by reference herein.

The present disclosure relates to methods for manufacturing absorbent articles, and in particular, to methods for making elastomeric laminates that may be used as components of absorbent articles. The elastomeric laminates may include a first substrate, a second substrate, and an elastic material positioned between the first substrate and second substrate. During the process of making the elastomeric laminate, the elastic material may be advanced and stretched in a machine direction and may be joined with either or both the first and second substrates advancing in the machine direction. The methods and apparatuses according to the present disclosure may be configured with a plurality of elastic strands wound onto a beam, and wherein one or more elastic strands may comprise a spin finish. During assembly of an elastomeric laminate, the beam is rotated to unwind the elastic strands from the beam. The elastic strands may also be stretched while advancing in a machine direction. Discrete mechanical bonds are applied to the first substrate and the second substrate to secure elastic strands therebetween, wherein the discrete bonds are arranged intermittently along the machine direction. As discussed in more detail below, when combining elastic strands having relatively low decitex values with substrates to create bonds having certain ranges of thicknesses, the mechanical bonds can be applied to secure the elastic strands between substrates without severing the elastics strands and without the need for nesting grooves in a mechanical bonding device. The bonding process can be achieved at relatively high substrate advancement speeds when utilizing mechanical bonding devices that require none or relatively small online adjustments, such as for example, patterned and anvil rolls and/or ultrasonic bonding devices with relatively low runout values.

During the bonding process, heat and pressure are applied to the first substrate and the second substrate such that malleable materials of the first and second substrates deform to completely surround an outer perimeter of a discrete length of the stretched elastic strand. After removing the heat and pressure from the first and second substrates, the malleable materials harden to define a bond conforming with a cross sectional shape defined by the outer perimeter of the stretched elastic strand. When the elastic strand is in a stretched state, the stretched elastic strand defines a cross sectional area that is less than a cross sectional area of the elastic strand when in a relaxed state. Thus, when tension is released from the elastic strand, the cross sectional area of the elastic strand is prevented from expanding in the bond by the hardened materials of the first and second substrates, which in turn, creates forces between the elastic strand and the hardened materials. The forces between the elastic strand and the hardened materials increases the friction between the elastic strand and the hardened materials. Thus, a frictional lock may be created between the elastic strand and the hardened materials in the bond region by releasing the tension from the stretched elastic strands. The frictional lock holds the discrete length of the elastic strand in a fixed position in the bond region with the first and second substrates.

To help provide additional context to the subsequent discussion of the process embodiments, the following provides a general description of absorbent articles in the form of diapers that include components including the elastomeric laminates that may be produced with the methods and apparatuses disclosed herein.

FIGS. 1A, 1B, and 2show an example of an absorbent article100in the form of a diaper pant100P that may include components constructed from elastomeric laminates assembled in accordance with the apparatuses and methods disclosed herein. In particular,FIGS. 1A and 1Bshow perspective views of a diaper pant100P in a pre-fastened configuration, andFIG. 2shows a plan view of the diaper pant100P with the portion of the diaper that faces away from a wearer oriented toward the viewer. The diaper pant100P includes a chassis102and a ring-like elastic belt104. As discussed below in more detail, a first elastic belt106and a second elastic belt108are bonded together to form the ring-like elastic belt104.

With continued reference toFIG. 2, the diaper pant100P and the chassis102each include a first waist region116, a second waist region118, and a crotch region119disposed intermediate the first and second waist regions. The first waist region116may be configured as a front waist region, and the second waist region118may be configured as back waist region. The diaper100P may also include a laterally extending front waist edge121in the front waist region116and a longitudinally opposing and laterally extending back waist edge122in the back waist region118. To provide a frame of reference for the present discussion, the diaper100P and chassis102ofFIG. 2are shown with a longitudinal axis124and a lateral axis126. In some embodiments, the longitudinal axis124may extend through the front waist edge121and through the back waist edge122. And the lateral axis126may extend through a first longitudinal or right side edge128and through a midpoint of a second longitudinal or left side edge130of the chassis102.

As shown inFIGS. 1A, 1B, and 2, the diaper pant100P may include an inner, body facing surface132, and an outer, garment facing surface134. The chassis102may include a backsheet136and a topsheet138. The chassis102may also include an absorbent assembly140, including an absorbent core142, disposed between a portion of the topsheet138and the backsheet136. As discussed in more detail below, the diaper100P may also include other features, such as leg elastics and/or leg cuffs to enhance the fit around the legs of the wearer.

As shown inFIG. 2, the periphery of the chassis102may be defined by the first longitudinal side edge128, a second longitudinal side edge130, a first laterally extending end edge144disposed in the first waist region116, and a second laterally extending end edge146disposed in the second waist region118. Both side edges128and130extend longitudinally between the first end edge144and the second end edge146. As shown inFIG. 2, the laterally extending end edges144and146are located longitudinally inward from the laterally extending front waist edge121in the front waist region116and the laterally extending back waist edge122in the back waist region118. When the diaper pant100P is worn on the lower torso of a wearer, the front waist edge121and the back waist edge122may encircle a portion of the waist of the wearer. At the same time, the side edges128and130may encircle at least a portion of the legs of the wearer. And the crotch region119may be generally positioned between the legs of the wearer with the absorbent core142extending from the front waist region116through the crotch region119to the back waist region118.

As previously mentioned, the diaper pant100P may include a backsheet136. The backsheet136may also define the outer surface134of the chassis102. The backsheet136may also comprise a woven or nonwoven material, polymeric films such as thermoplastic films of polyethylene or polypropylene, and/or a multi-layer or composite materials comprising a film and a nonwoven material. The backsheet may also comprise an elastomeric film. An example backsheet136may be a polyethylene film having a thickness of from about 0.012 mm (0.5 mils) to about 0.051 mm (2.0 mils). Further, the backsheet136may permit vapors to escape from the absorbent core (i.e., the backsheet is breathable) while still preventing exudates from passing through the backsheet136.

Also described above, the diaper pant100P may include a topsheet138. The topsheet138may also define all or part of the inner surface132of the chassis102. The topsheet138may be liquid pervious, permitting liquids (e.g., menses, urine, and/or runny feces) to penetrate through its thickness. A topsheet138may be manufactured from a wide range of materials such as woven and nonwoven materials; apertured or hydroformed thermoplastic films; apertured nonwovens, porous foams; reticulated foams; reticulated thermoplastic films; and thermoplastic scrims. Woven and nonwoven materials may comprise natural fibers such as wood or cotton fibers; synthetic fibers such as polyester, polypropylene, or polyethylene fibers; or combinations thereof. If the topsheet138includes fibers, the fibers may be spunbond, carded, wet-laid, meltblown, hydroentangled, or otherwise processed as is known in the art. Topsheets138may be selected from high loft nonwoven topsheets, apertured film topsheets and apertured nonwoven topsheets. Exemplary apertured films may include those described in U.S. Pat. Nos. 5,628,097; 5,916,661; 6,545,197; and 6,107,539.

As mentioned above, the diaper pant100P may also include an absorbent assembly140that is joined to the chassis102. As shown inFIG. 2, the absorbent assembly140may have a laterally extending front edge148in the front waist region116and may have a longitudinally opposing and laterally extending back edge150in the back waist region118. The absorbent assembly may have a longitudinally extending right side edge152and may have a laterally opposing and longitudinally extending left side edge154, both absorbent assembly side edges152and154may extend longitudinally between the front edge148and the back edge150. The absorbent assembly140may additionally include one or more absorbent cores142or absorbent core layers. The absorbent core142may be at least partially disposed between the topsheet138and the backsheet136and may be formed in various sizes and shapes that are compatible with the diaper. Exemplary absorbent structures for use as the absorbent core of the present disclosure are described in U.S. Pat. Nos. 4,610,678; 4,673,402; 4,888,231; and 4,834,735.

Some absorbent core embodiments may comprise fluid storage cores that contain reduced amounts of cellulosic airfelt material. For instance, such cores may comprise less than about 40%, 30%, 20%, 10%, 5%, or even 1% of cellulosic airfelt material. Such a core may comprise primarily absorbent gelling material in amounts of at least about 60%, 70%, 80%, 85%, 90%, 95%, or even about 100%, where the remainder of the core comprises a microfiber glue (if applicable). Such cores, microfiber glues, and absorbent gelling materials are described in U.S. Pat. Nos. 5,599,335; 5,562,646; 5,669,894; and 6,790,798 as well as U.S. Patent Publication Nos. 2004/0158212 A1 and 2004/0097895 A1.

As previously mentioned, the diaper100P may also include elasticized leg cuffs156. It is to be appreciated that the leg cuffs156can be and are sometimes also referred to as leg bands, side flaps, barrier cuffs, elastic cuffs or gasketing cuffs. The elasticized leg cuffs156may be configured in various ways to help reduce the leakage of body exudates in the leg regions. Example leg cuffs156may include those described in U.S. Pat. Nos. 3,860,003; 4,909,803; 4,695,278; 4,795,454; 4,704,115; 4,909,803; and U.S. Patent Publication No. 2009/0312730 A1.

As mentioned above, diaper pants may be manufactured with a ring-like elastic belt104and provided to consumers in a configuration wherein the front waist region116and the back waist region118are connected to each other as packaged, prior to being applied to the wearer. As such, diaper pants may have a continuous perimeter waist opening110and continuous perimeter leg openings112such as shown inFIGS. 1A and 1B. The ring-like elastic belt may be formed by joining a first elastic belt to a second elastic belt with a permanent side seam or with an openable and reclosable fastening system disposed at or adjacent the laterally opposing sides of the belts.

As previously mentioned, the ring-like elastic belt104may be defined by a first elastic belt106connected with a second elastic belt108. As shown inFIG. 2, the first elastic belt106extends between a first longitudinal side edge111aand a second longitudinal side edge111band defines first and second opposing end regions106a,106band a central region106c. And the second elastic108belt extends between a first longitudinal side edge113aand a second longitudinal side edge113band defines first and second opposing end regions108a,108band a central region108c. The distance between the first longitudinal side edge111aand the second longitudinal side edge111bdefines the pitch length, PL, of the first elastic belt106, and the distance between the first longitudinal side edge113aand the second longitudinal side edge113bdefines the pitch length, PL, of the second elastic belt108. The central region106cof the first elastic belt is connected with the first waist region116of the chassis102, and the central region108cof the second elastic belt108is connected with the second waist region118of the chassis102. As shown inFIGS. 1A and 1B, the first end region106aof the first elastic belt106is connected with the first end region108aof the second elastic belt108at first side seam178, and the second end region106bof the first elastic belt106is connected with the second end region108bof the second elastic belt108at second side seam180to define the ring-like elastic belt104as well as the waist opening110and leg openings112.

As shown inFIGS. 2, 3A, and 3B, the first elastic belt106also defines an outer laterally extending edge107aand an inner laterally extending edge107b, and the second elastic belt108defines an outer laterally extending edge109aand an inner laterally extending edge109b. As such, a perimeter edge112aof one leg opening may be defined by portions of the inner laterally extending edge107bof the first elastic belt106, the inner laterally extending edge109bof the second elastic belt108, and the first longitudinal or right side edge128of the chassis102. And a perimeter edge112bof the other leg opening may be defined by portions of the inner laterally extending edge107b, the inner laterally extending edge109b, and the second longitudinal or left side edge130of the chassis102. The outer laterally extending edges107a,109amay also define the front waist edge121and the laterally extending back waist edge122of the diaper pant100P. The first elastic belt and the second elastic belt may also each include an outer, garment facing layer162and an inner, wearer facing layer164. It is to be appreciated that the first elastic belt106and the second elastic belt108may comprise the same materials and/or may have the same structure. In some embodiments, the first elastic belt106and the second elastic belt may comprise different materials and/or may have different structures. It should also be appreciated that the first elastic belt106and the second elastic belt108may be constructed from various materials. For example, the first and second belts may be manufactured from materials such as plastic films; apertured plastic films; woven or nonwoven webs of natural materials (e.g., wood or cotton fibers), synthetic fibers (e.g., polyolefins, polyamides, polyester, polyethylene, or polypropylene fibers) or a combination of natural and/or synthetic fibers; or coated woven or nonwoven webs. In some embodiments, the first and second elastic belts include a nonwoven web of synthetic fibers, and may include a stretchable nonwoven. In other embodiments, the first and second elastic belts include an inner hydrophobic, non-stretchable nonwoven material and an outer hydrophobic, non-stretchable nonwoven material.

The first and second elastic belts106,108may also each include belt elastic material interposed between the outer substrate layer162and the inner substrate layer164. The belt elastic material may include one or more elastic elements such as strands, ribbons, films, or panels extending along the lengths of the elastic belts. As shown inFIGS. 2, 3A, and 3B, the belt elastic material may include a plurality of elastic strands168which may be referred to herein as outer, waist elastics170and inner, waist elastics172. Elastic strands168, such as the outer waist elastics170, may continuously extend laterally between the first and second opposing end regions106a,106bof the first elastic belt106and between the first and second opposing end regions108a,108bof the second elastic belt108. In some embodiments, some elastic strands168, such as the inner waist elastics172, may be configured with discontinuities in areas, such as for example, where the first and second elastic belts106,108overlap the absorbent assembly140. In some embodiments, the elastic strands168may be disposed at a constant interval in the longitudinal direction. In other embodiments, the elastic strands168may be disposed at different intervals in the longitudinal direction. The belt elastic material in a stretched condition may be interposed and joined between the uncontracted outer layer and the uncontracted inner layer. When the belt elastic material is relaxed, the belt elastic material returns to an unstretched condition and contracts the outer layer and the inner layer. The belt elastic material may provide a desired variation of contraction force in the area of the ring-like elastic belt. It is to be appreciated that the chassis102and elastic belts106,108may be configured in different ways other than as depicted inFIG. 2. The belt elastic material may be joined to the outer and/or inner layers continuously or intermittently along the interface between the belt elastic material and the inner and/or outer belt layers.

In some configurations, the first elastic belt106and/or second elastic belt108may define curved contours. For example, the inner lateral edges107b,109bof the first and/or second elastic belts106,108may include non-linear or curved portions in the first and second opposing end regions. Such curved contours may help define desired shapes to leg opening112, such as for example, relatively rounded leg openings. In addition to having curved contours, the elastic belts106,108may include elastic strands168,172that extend along non-linear or curved paths that may correspond with the curved contours of the inner lateral edges107b,109b.

It is to be appreciated that the apparatuses and methods of assembly of elastomeric laminates and absorbent articles described herein and illustrated in the accompanying drawings are non-limiting example configurations. The features illustrated or described in connection with one non-limiting configuration may be combined with the features of other non-limiting configurations. Such modifications and variations are intended to be included within the scope of the present disclosure.

As previously mentioned, apparatuses and methods according to the present disclosure may be utilized to produce elastomeric laminates that may be used to construct various components of diapers, such as elastic belts, leg cuffs, and the like. For example,FIGS. 4-17show schematic views of converting apparatuses300adapted to manufacture elastomeric laminates302. As described in more detail below, the converting apparatuses300shown inFIGS. 4-17operate to advance a continuous length of elastic material304, a continuous length of a first substrate306, and a continuous length of a second substrate308along a machine direction MD. It is also to be appreciated that in some configurations, the first substrate306and second substrate308herein may be defined by two discrete substrates or may be defined by folded portions of a single substrate. The apparatus300stretches the elastic material304and joins the stretched elastic material304with the first and second substrates306,308to produce an elastomeric laminate302. Although the elastic material304is illustrated and referred to herein as strands, it is to be appreciated that elastic material304may include one or more continuous lengths of elastic strands, ribbons, and/or films.

It is to be appreciated that the elastomeric laminates302can be used to construct various types of absorbent article components. It also to be appreciated that the methods and apparatuses herein may be adapted to operate with various types of absorbent article assembly processes, such as disclosed for example in U.S. Patent Publication Nos. 2013/0255861 A1; 2013/0255862 A1; 2013/0255863 A1; 2013/0255864 A1; and 2013/0255865 A1. For example, the elastomeric laminates302may be used as a continuous length of elastomeric belt material that may be converted into the first and second elastic belts106,108discussed above with reference toFIGS. 1-3B. As such, the elastic material304may correspond with the belt elastic material168interposed between the outer layer162and the inner layer164, which in turn, may correspond with either the first and/or second substrates306,308. In other examples, the elastomeric laminates may be used to construct waistbands and/or side panels in taped diaper configurations. In yet other examples, the elastomeric laminates may be used to construct various types of leg cuff and/or topsheet configurations.

As discussed in more detail below, the converting apparatuses300may include metering devices arranged along a process machine direction MD, wherein the metering devices may be configured to stretch the advancing elastic material and/or join stretch elastic material with one or more advancing substrates. In some configurations, a metering device may comprise a beam of elastic strands wound thereon. During operation, elastic material may advance in a machine direction from a rotating beam to a downstream metering device to be joined with one or more advancing substrates. Bonds are applied to the first substrate and the second substrate to secure discrete lengths of the stretched elastic strands between the first and second substrates. The discrete bonds may be arranged intermittently along the machine direction. In some configurations, the bonds extend in the machine direction and may extend in a cross direction across one or more elastic strands. In some configurations, bonds may be separated from each other in a cross direction. It is to be appreciated that the apparatuses and methods of assembly of elastomeric laminates and absorbent articles described herein and illustrated in the accompanying drawings are non-limiting example configurations. The features illustrated or described in connection with one non-limiting configuration may be combined with the features of other non-limiting configurations. Such modifications and variations are intended to be included within the scope of the present disclosure.

As shown inFIGS. 5 and 6, a converting apparatus300for producing an elastomeric laminate302may include a first metering device310and a second metering device312. The first metering device310may be configured as a beam314with a plurality of elastic strands316wound thereon.FIG. 4shows an example of an empty beam314that includes two side plates317a,317bthat may be connected with opposing end portions of a mandrel core318, wherein elastic strands may be wound onto the mandrel core318. It is to be appreciated that beams of various sizes and technical specifications may be utilized in accordance with the methods and apparatuses herein, such as for example, beams that are available from ALUCOLOR Textilmaschinen, GmbH. During operation, the plurality of elastic strands316advance in the machine direction MD from the beam314to the second metering device312. In addition, the plurality of elastic strands316may be stretched along the machine direction MD between the beam314and the second metering device312. The stretched elastic strands316are also joined with a first substrate306and a second substrate308at the second metering device312to produce an elastomeric laminate302. In some configurations, one or more of the elastic strands316advancing from the beam314may also include a spin finish320located on outer surfaces of the elastics strands. In turn, stretched elastic strands316may be connected between the first substrate306and the second substrate308with bonds322. The bonds322may be configured as discrete mechanical bonds322applied to the first substrate306and the second substrate308to secure the elastic strands316. The discrete bonds322may be arranged intermittently along the machine direction. In some configurations, the bonds322extend in the machine direction MD and may extend in the cross direction CD across one or more elastic strands316. In some configurations, discrete bonds322may also be separated from each other in the cross direction CD.

As shown inFIGS. 5 and 6, the second metering device312may include: a first roller324having an outer circumferential surface326and that rotates about a first axis of rotation328, and a second roller330having an outer circumferential surface332and that rotates about a second axis of rotation334. The first roller324and the second roller330rotate in opposite directions, and the first roller324is adjacent the second roller330to define a nip336between the first roller324and the second roller330. The first roller324rotates such that the outer circumferential surface326has a surface speed S1, and the second roller330may rotate such that the outer circumferential surface332has the same, or substantially the same, surface speed S1.

With continued reference toFIGS. 5 and 6, the first substrate306includes a first surface338and an opposing second surface340, and the first substrate306advances to the first roller324. In particular, the first substrate306advances at speed S1 to the first roller324where the first substrate306partially wraps around the outer circumferential surface326of the first roller324and advances through the nip336. As such, the first surface338of the first substrate306travels in the same direction as and in contact with the outer circumferential surface326of the first roller324. In addition, the second substrate308includes a first surface342and an opposing second surface344, and the second substrate308advances to the second roller330. In particular, the second substrate308advances at speed S1 to the second roller330where the second substrate308partially wraps around the outer circumferential surface332of the second roller330and advances through the nip336. As such, the second surface344of the second substrate308travels in the same direction as and in contact with the outer circumferential surface332of the second roller330.

Still referring toFIGS. 5 and 6, the beam314includes elastic strands316wound thereon, and the beam314is rotatable about a beam rotation axis346. In some configurations, the beam rotation axis346may extend in the cross direction CD. As the beam314rotates, the elastic strands316advance from the beam314at a speed S2 with the elastic strands316being spaced apart from each other in the cross direction CD. From the beam314, the elastic strands316advance in the machine direction MD to the nip336. In some configurations, the speed S2 is less than the speed S1, and as such, the elastic strands316are stretched in the machine direction MD. In turn, the stretched elastic strands316advance through the nip336between the first and second substrates306,308such that the elastic strands316are joined with the second surface340of the first substrate306and the first surface342of the second substrate308to produce a continuous length of elastomeric laminate302.

It is to be appreciated that the beam314may be configured in various ways and with various quantities of elastic strands. Example beams, also referred to as warp beams, that may be used with the apparatus and methods herein are disclosed in U.S. Pat. Nos. 4,525,905; 5,060,881; and 5,775,380; and U.S. Patent Publication No. 2004/0219854 A1. AlthoughFIG. 6shows five elastic strands316advancing from the beam314, it is to be appreciated that the apparatuses herein may be configured such that more or less than five elastic strands316advance from the beam314. In some configurations, the elastic strands316advancing from the beam314may include from about 100 to about 2000 strands, specifically reciting all 1 strand increments within the above-recited range and all ranges formed therein or thereby. In some configurations, the elastic strands316may be separated from each other by about 0.4 mm to about 4 mm in the cross direction, specifically reciting all 0.1 mm increments within the above-recited range and all ranges formed therein or thereby. As discussed herein, the elastics in the plurality of elastic strands may be pre-strained prior to joining the elastic strand to the first or second substrate layers306,308. In some configurations, the elastic may be pre-strained from about 75% to about 300%, specifically reciting all 1% increments within the above-recited range and all ranges formed therein or thereby. It is also to be appreciated that one or more beams of elastics may be arranged along the cross direction CD of a converting process and/or arranged along a machine direction MD in various different portions of a converting process. It is also to be appreciated that the beam314can be connected with one or more motors, such as servo motors, to drive and control the rotation of the beam314. It is to be appreciated that in some configurations, the elastic strands316may be supplied on the beam314in a stretched state, and as such, may not require additional stretching (or may require relatively less additional stretching) before being combined with the first substrate306and/or the second substrate308. In some configurations, an elastic strand316may be drawn from a single roll utilizing a rolling unwind, such as for example, available from Overend Technologies, Inc.

With continued reference toFIGS. 5 and 6, the advancing elastic strands316may be joined with the first substrate306and the second substrate308to form the elastomeric laminate302. The elastic laminate302may also advance past a bond applicator500configured to apply bonds322that secure the elastic strands316between the first substrate306and the second substrate308. One or more of the elastic strands316advancing from the beam314may include a spin finish320. As such, the bonds322may be configured to secure the elastic strands316between the first and second substrates306,308without having to remove the spin finish320from the elastic strands316. It is also to be appreciated that the methods and apparatuses herein may also be configured to remove the spin finish320from the elastic strands316. Examples of spin finish removal processes and apparatuses are disclosed in U.S. Provisional Patent Application No. 62/483,965, which is incorporated by reference herein. The spin finish removal apparatus may be configured to apply detergent to an advancing elastic strand and may also wipe and/or dry the advancing elastic strand. The treated stretched elastic strand may then be connected between a first substrate and a second substrate. In addition, the elastic laminates302herein may be constructed with or without adhesives between the first and second substrates306,308. In addition, it is to be appreciated that the bonding methods and apparatuses herein may be utilized in conjunction with other bonding methods and apparatuses, such as disclosed in U.S. Patent Application No. 62/553,149, filed on Sep. 1, 2017, which is incorporated by reference herein.

It is to be appreciated that one or more of the elastic strands316may include various types of spin finish320, also referred herein as yarn finish, configured as coating on the elastic strands316that may be intended to help prevent the elastics strands from adhering to themselves, each other, and/or downstream handling equipment. In some configurations, a spin finish may include various types of oils and other components, such as disclosed for example in U.S. Pat. Nos. 8,377,554; 8,093,161; and 6,821,301. In some configurations, a spin finish may include various types of silicone oils, such as for example, polydimethylsiloxane. In some configurations, a spin finish may include various types of mineral oils. It is to be appreciated that the amount of spin finish applied to elastic strands may be optimized depending on the process configuration in which the elastic strands may be used. For example, in process configurations wherein elastic strands have limited contact or do not contact downstream handling equipment, such as idlers, the amount of spin finish may be selected to help prevent the elastics strands from adhering to themselves and/or each other while wound on a beam without regard to whether elastic strands would adhere to downstream handling equipment. As such, it is to be appreciated that the elastic strands herein may include various amounts of spin finish that may be expressed in various ways. For example, a quantity of 10 grams of spin finish per 1 kilogram of elastic strand may be expressed as 1% spin finish. In some configurations, an elastic strand may include about 0.1% spin finish. In some configurations, a strand may include from about 0.01% to about 10% spin finish, specifically reciting all 0.01% increments within the above-recited range and all ranges formed therein or thereby.

As shown inFIG. 6, the bonds322may extend for discrete lengths along the machine direction MD and may be intermittently arranged along the machine direction of the elastic laminate302. Thus, the elastic strands316may extend in the machine direction MD between intermittently spaced bond regions360and unbonded regions362. It is to be appreciated that the bonds322may extend contiguously for various lengths in the cross direction CD and may extend across one or more elastic strands316. The bonds322may also be separated from each other in the cross direction CD, such as shown for example inFIG. 11.

FIGS. 7A and 8Aare detailed views of an elastic strand316in a stretched state secured with bonds322between the first and second substrates306,308. During the bonding process, the bond applicator500may apply heat and pressure to a first region350of the first substrate306and a second region352of the second substrate308such that first material354of the first substrate306and second material356of the second substrate308become malleable. In turn, the malleable first and second materials354,356deform and completely surround an outer perimeter358of a discrete length of the stretched elastic strand316in a bond region360. The heat and pressure are removed from the first region350of the first substrate306and the second region352of the second substrate308as the elastic laminate302advances from the bond applicator500, and as such, the malleable first and second materials354,356harden in a bond322that conforms with a cross sectional shape defined by the outer perimeter358of the stretched elastic strand316. In some configurations, an external heat source may be used to generate the heat used in the bonding process, such as with a heated anvil. It is also to be appreciated that heat may be generated solely by the bonding process, such as for example, heat generated by an ultrasonic horn vibration or heat generated by a fusion bonding process, wherein no external heat source is required. In some configurations, tooling used in the bonding process may also be chilled to help provide and/or control the process temperatures at desired levels.

It is to be appreciated that the bond applicator500may be configured in various ways, such as for example, heated or unheated patterned and anvil rolls and/or ultrasonic bonding devices. For example, the bond applicator500schematically shown inFIGS. 5 and 5Amay include an anvil configured as a pattern roll502with a pressing surface504adjacent the pattern roll502. The pattern roll502may be adapted to rotate about an axis of rotation506extending axially in the cross direction CD. During operation, the elastomeric laminate302may be partially wrapped onto the pattern roll502. And the pattern roll502rotates about the axis of rotation506to advance the elastomeric laminate302through a nip508between the pattern roll502and the pressing surface504. As shown inFIG. 5, the bond applicator500may also include one or more rolls503that help guide the elastomeric laminate to and from the pattern roll502. The pattern roll502may also comprise one or more bonding surfaces510, also referred to herein as pattern surfaces, defined by one or more bonding elements512, also referred to herein as pattern elements, extending radially outward from an outer circumferential surface514. As the elastomeric laminate302is advanced between the bonding surface510and the pressing surface504, the first substrate306and the second substrate308are welded together to create bonds322between the first substrate306and the second substrate308.

During the assembly operation, the elastomeric laminate302may be partially wrapped onto the pattern roll502. As shown inFIG. 5, the extent that the elastomeric laminate302wraps around the pattern roll502is referred to herein as the wrap angle, θ, and may be expressed in units of degrees. In some configurations, the wrap angle, θ, may be greater than zero degrees and less than or equal to 180 degrees, specifically reciting all 1 degree increments within the above-recited range and all ranges formed therein or thereby. In some configurations, the wrap angle, θ, may be greater 180 degrees.

It is to be appreciated that various operational abnormalities may result while elastic strands316are advancing from a beam314during assembly operations disclosed herein. For example, breakouts may occur during assembly operations, wherein one or more elastic strands316unintentionally breaks while advancing from the beam314during assembly of the elastomeric laminate302. The methods and apparatuses herein may be configured to help isolate broken elastic strands and rethread broken elastic strands. For example, as discussed above with reference toFIG. 5, the elastomeric laminate302may be partially wrapped onto the pattern roll502for a partial wrap angle, θ1, before advancing through the nip508. As such, elastic strands316that may be unintentionally broken at the nip508may begin to retract upstream from the nip. However, at relatively higher advancement speeds S1, there is less time for the broken elastic strand to retract. As such, the broken elastic strand may be pulled forward while sandwiched between the advancing first and second substrates306,308through the nip508at a speed that is greater than the rate of retraction. In turn, the broken elastic strand316may be automatically rethreaded. A control parameter to help mitigate elastic retraction would be the size of the partial wrap angle, θ1, and the web tension.

It is to be appreciated that the pressing surface504may be configured in various ways. For example, as shown inFIGS. 5 and 5A, the pressing surface504may comprise an energy transfer surface of an ultrasonic bonding device518. As such, the bond applicator500may include a horn520and may be configured to impart ultrasonic energy to the combined substrates306,308and elastic strands316on the pattern roll502. The ultrasonic bonding device518may apply energy to the horn520to create resonance of the horn520at frequencies and amplitudes so the horn vibrates rapidly in a direction generally perpendicular to the substrates306,308and elastic strands316being advanced past the horn520on the pattern roll502. Vibration of the horn520creates bonds322and/or bond regions360by generating heat to melt and bond the substrates306,308together in areas supported by the bonding surface510on the pattern roll502. Thus, the bonds322and/or bond regions360may have shapes that correspond with and may mirror shape of the bonding surfaces510. As shown inFIG. 5A, the pattern surface510may extend contiguously across one or more elastic strands316positioned between the first substrate306, and the second substrate308.

It is to be appreciated that the number, size, and shape of some or all the pattern surfaces510and/or pattern elements512may be different. In some configurations, the shape and size of the pattern surface510of each pattern element512may be identical or substantially identical to each other. In some configurations, the pattern elements512and/or pattern surfaces510may have a perimeter that defines circular, square, rectangular, elliptical, and various types of other shapes. In some configurations, the anvil502may include a pattern element512with a pattern surface510that defines a continuous crossing line pattern and/or various other shapes, such as disclosed in U.S. Pat. No. 9,265,672, which is incorporated by reference herein. It is to be appreciated that the choice of pattern surface shape may enable the creation of unique textures and patterns where the location and size of the bonding sites impact local buckling resistance of a nonwoven laminate and may create desired homogeneous textures upon relaxation of the elastics and the resulting nonwoven corrugation. It is also to be appreciated that the pattern elements512and comprise pattern surfaces with chamfered or radial, curved edges.

Some bond applicators may be configured to a maintain relatively constant distance between the pressing surface504and the pattern surface510. For example, some ultrasonic bonding devices518may be configured to move the horn520toward and away from the pattern surface510to help maintain a relatively constant distance between them. To help maintain relatively consistent bond quality without cutting the elastic strands316, the speeds at which such a horn520would have to move back and forth increases as speeds at which the substrates306,308and elastic strands316advance through the nip508. Pattern rolls502with comprising relatively small runout values may help mitigate requirements for such increased speeds of horn520movement. As such, it is to be appreciated that the pattern roll502may be configured with pattern surfaces510extending for various lengths in the cross direction CD and comprising various total runout values. For example, in some configurations, the pattern roll502may include pattern surfaces510extending in the cross direction for a length of at least about 100 mm. In some configurations, the pattern roll502may include pattern surfaces510comprising total runout values ranging from about 0 μm (“microns”) to about 10 μm, specifically reciting all 1 μm increments within the above-recited range and all ranges formed therein or thereby. The term “total runout” refers herein to the total runout as defined in ASME Y14.5-2009.

It is to be appreciated that aspects of the ultrasonic bonding devices518may be configured in various ways, such as for example linear or rotary type configurations, and such as disclosed for example in U.S. Pat. Nos. 3,113,225; 3,562,041; 3,733,238; 5,110,403; 6,036,796; 6,508,641; and 6,645,330. In some configurations, the ultrasonic bonding device518may be configured as a linear oscillating type sonotrode, such as for example, available from Herrmann Ultrasonic, Inc. In some configurations, the sonotrode may include a plurality of sonotrodes nested together in the cross direction CD. The bond applicator500may also be configured in various other ways, such as for example, the mechanical bonding devices and methods disclosed in U.S. Pat. Nos. 4,854,984; 6,248,195; 8,778,127; and 9,005,392; and U.S. Patent Publication Nos. 2014/0377513 A1; and 2014/0377506 A1. Although the bond applicator500is shown inFIGS. 5 and 6as a separate device that is positioned downstream of the second metering device312, it is to be appreciated the second metering device312may also be configured as the bond applicator500. As such, the first substrate306, second substrate308, and elastic strands316may be combined and bonded together at the bond applicator500to form the elastic laminate302.

It is to be appreciated that the combined first substrate306, second substrate308, and elastic strands316may advance at various speeds S1 through the bonding process. For example, in some configurations, the combined first substrate306, second substrate308, and elastic strands316may advance in the machine direction MD through the nip508between the pattern roll502and the pressing surface504at speeds ranging from about 100 meters per minute to about 450 meters per minute, specifically reciting all 1 meter per minute increments within the above-recited range and all ranges formed therein or thereby.

As previously mentioned, a frictional lock may be applied between a portion of the elastic strand316and the hardened first and second materials354,356by releasing tension from the stretched elastic strand316. The frictional lock acts to hold and/or secure the elastic strand316in a fixed position in the bond region360. For the purposes of a general explanation,FIG. 7Bshows a length of an elastic strand316in a unstretched or relaxed state, wherein the elastic strand316defines a first cross sectional area A1. AndFIG. 7Cshows a length of the elastic strand316fromFIG. 7Bin a stretched state, wherein the elastic strand316defines a second cross sectional area A2 that is less than the first cross sectional area A1. Thus, the cross sectional area of the stretched elastic strand316expands when tension is partially or fully released from the elastic strand316. As discussed in more detail below, the tendency of the cross sectional area of the elastic strand316to expand helps create the frictional lock.

Turning next toFIG. 7D, a detailed view of an elastic strand316, such as shown inFIG. 7A, is provided wherein tension has been released (or reduced) on the elastic strand316and showing how the tendency of the elastic strand316to expand creates a frictional lock in the bonded region360.FIGS. 7D and 8Bshow the elastic strand316as having a first cross sectional area A1 in an unbonded region362of the elastic laminate302, wherein the first cross sectional area A1 is greater than the second cross sectional area A2 of the stretched elastic strand316shown inFIGS. 7A and 8A. AndFIGS. 7D and 8Cshow the elastic strand316as having a third cross sectional area A3 in the bond region360of the elastic laminate302, wherein the third cross sectional area A3 is the same or about the same as the second cross sectional area A2 of the stretched elastic strand316shown inFIGS. 7A and 8A. As shown inFIG. 8C, the hardened first and second materials354,356in the bond region360help prevent the cross sectional area of the elastic strand316from expanding when tension has on elastic strand316has been reduced. The tendency of the elastic strand316to expand creates forces F (represented by dashed double arrow lines inFIG. 8C) exerted between the hardened first and second materials354,356in the bond region360. In turn, the forces F between the elastic strand316and the hardened first and second materials354,356creates a frictional lock by increasing the friction forces between the elastic strand316and the hardened materials354,356. The increased friction forces in the machine direction MD along the length of the elastic strand316in the bond region360holds the discrete length of the elastic strand316in a fixed position in the bond region360together with the first and second substrates306,308. As such, in some configurations, no adhesive may be applied to and/or present between the elastic strand316and the hardened materials354,356. It is also to be appreciated that in some configurations, adhesive may be applied to and/or present between the elastic strand316and the hardened materials354,356to help the frictional lock hold the discrete length of the elastic strand316in a fixed position in the bond region360together with the first and second substrates306,308. In some configurations, adhesive and the frictional lock in the bond regions360may share the load exerted by elastic strand316. In some configurations, adhesive positioned on the elastic strand316may increase the coefficient of friction between the elastic strand316and the hardened materials354,356in the bond region360. It is to be appreciated that various quantities of adhesive may be present in the bond regions360, such as for example, about 10 gsm or less.

It is also to be appreciated that the elastic strands316herein bonded in accordance with the methods described herein may also be constructed from one or more filaments364. For example,FIG. 9Ashows a cross sectional view of an elastic strand316in a bond region360wherein the elastic strand316comprises a plurality of individual filaments364. As shown inFIG. 9A, the elastics strand316includes outer filaments364asurrounding an inner filament364b. The outer filaments364adefine the outer perimeter358of the elastic strand316, and the outer filaments364amay surround the inner filament364bsuch that the inner filament364bis not in contact with the hardened first material354and the hardened second material356in the bond322. It is to be appreciated that the filaments364may be arranged in various positions within the bond region360. For example,FIG. 9Bshows a cross sectional view of an elastic strand316in a bond region360wherein the plurality of individual filaments364together define a perimeter358that is elongated along the cross direction CD, and wherein all of the plurality of filaments364are in contact with hardened first material354and hardened second material356. In another example,FIG. 9Cshows a cross sectional view of an elastic strand316in a bond region360wherein at least two of the filaments364are separated from each other by at least one of hardened first material354and hardened second material356.

It is to be appreciated that different components may be used to construct the elastomeric laminates302in accordance with the methods and apparatuses herein. For example, the first and/or second substrates306,308may include nonwovens and/or films and may be constructed from various types of materials, such as plastic films; apertured plastic films; woven or nonwoven webs of natural materials, such as wood or cotton fibers; synthetic fibers, such as polyolefins, polyamides, polyester, polyethylene, or polypropylene fibers or a combination of natural and/or synthetic fibers; or coated woven or nonwoven webs; polymeric films such as thermoplastic films of polyethylene or polypropylene, and/or a multi-layer or composite materials comprising a film and a nonwoven material. In some configurations, the first and/or second substrates306,308may include nonwovens configured with basis weight values of at least about 10 gsm, and may include nonwovens configured with basis weight values ranging from about 10 gsm to about 30 gsm, specifically reciting all 1 gsm increments within the above-recited range and all ranges formed therein or thereby.

It is also to be appreciated that the strands316and/or filaments364herein may define various different cross-sectional shapes. For example, in some configurations, strands316or filaments364may define circular, oval, or elliptical cross sectional shapes or irregular shapes, such as dog bone and hourglass shapes. In addition, the elastic strands316may be configured in various ways and with various decitex values. In some configurations, the elastic strands316may be configured with decitex values ranging from about 40 decitex to about 150 decitex, and may be configured with decitex values ranging from about 10 decitex to about 500 decitex, specifically reciting all 1 decitex increments within the above-recited range and all ranges formed therein or thereby.

As previously mentioned, substrates306,308with elastic strands316positioned therebetween can be bonded in accordance with methods herein without severing the elastics strands and without the need for nesting grooves in bond applicator500. For example, as shown inFIGS. 8C and 9A-9C, heat and pressure may be applied to the substrates306,308to create bonds322surrounding the elastic strand316. The bond322is defined by hardened first material354and hardened second material356and has a minimum thickness Tb. In addition, the elastic strand316may have a thickness Te in the bond region360. In some configurations, substrates306,308that are bonded together to create a bond thickness Tb having a certain size relative to the elastic strand thickness Te, the elastic strand316may not be severed during the bonding process. In addition, the forces F exerted between the elastic strand316and the hardened first and second materials354,356in the bond region360may be prevented from breaking the bond322. Such a relationship between Te and Tb may be characterized by the decitex of elastic strands316and the bond thickness Tb. For example, substrates306,308may be bonded together with an elastic strand having a decitex value less than or equal to about 70 positioned therebetween to create a bond322having a thickness Tb of at least about 100 μm (“microns”) without severing the elastic strand316. In another example, substrates306,308may be bonded together with an elastic strand having a decitex value less than or equal to about 250 positioned therebetween to create a bond322having a thickness Tb of at least about 200 μm (“microns”) without severing the elastic strand316. In some configurations, such as shown inFIG. 9C, the bond thickness Tb may be at least 50% larger than the minimum cross sectional thickness Tf a filament364. For example, as shown inFIG. 9C, the minimum cross sectional thickness Tf of a filament364having a circular cross section may be defined the diameter of such a filament.

FIGS. 9D-9Felectron microscope photographs (“SEM”) showing cross sectional views of an elastic strand316in a bond region360surrounded by hardened first and second materials354,356from two nonwovens. InFIGS. 9D and 9E, the elastic strand316is a 70 decitex elastic strand including five filaments364, wherein each filament364has a diameter of about 43 μm (“microns”). And the bond322defines a thickness Tb of about 80 μm (“microns”). InFIG. 9F, the elastic strand316is a 235 decitex elastic strand including fifteen filaments364, wherein each filament364has a diameter of about 43 μm (“microns”). And the bond322defines a thickness Tb of about 200 μm (“microns”).

It is to be appreciated that the apparatuses300herein may be configured in various ways with various features described herein to assemble elastomeric laminates302having various stretch characteristics. For example, the apparatus300may be configured to assemble elastomeric laminates302with elastic strands316unwound from more than one beam and/or in combination with elastic stands supplied from an overend or surface driven unwinder. For example,FIGS. 10 and 11illustrate the apparatus300configured to assemble elastomeric laminates302with elastic strands316unwound from more than one beam314. In particular, the apparatus300may include a first beam314awith first elastic strands316awound thereon and a second beam314bwith second elastic strands316bwound thereon. The first beam314ais rotatable about a first beam rotation axis346a, and the second beam314bis rotatable about a second beam rotation axis346b. During operation, as the first beam314arotates, the first elastic strands316aadvance in the machine direction MD from the first beam314aat a speed S2 with the first elastic strands316abeing spaced apart from each other in the cross direction CD. From the first beam314a, the first elastic strands316aadvance in the machine direction MD and are joined with the first substrate306and the second substrate308as discussed above. Similarly, as the second beam314brotates, the second elastic strands316badvance in the machine direction MD from the second beam314bat a speed S3 with the second elastic strands316bbeing spaced apart from each other in the cross direction CD. From the second beam314b, the second elastic strands316badvance in the machine direction MD and are joined with the first substrate306and the second substrate308as discussed above. It is also to be appreciated that the apparatus configuration shown inFIGS. 10 and 11may also include the bond applicator500arranged to apply the bonds322as discussed above. The bond applicator500is generically represented by a dashed-line rectangle inFIG. 10.

With continued reference toFIGS. 10 and 11, the elastic strands316a,316bmay be joined with the first and second substrates306,308such that the elastomeric laminate302may have different stretch characteristics in different regions along the cross direction CD. For example, when the elastomeric laminate302is elongated, the first elastic strands316amay exert contraction forces in the machine direction MD that are different from contraction forces exerted by the second elastic strands316b. Such differential stretch characteristics can be achieved by stretching the first elastic strands316amore or less than the second elastic strands316bbefore joining the elastic strands316a,316bwith the first and second substrates306,308. For example, as previously discussed, the first substrate306and the second substrate308may each advance at a speed S1. In some configurations, the first elastic strands316amay advance from the first beam314aat speed S2 that is less than the speed S1, and second elastic strands316bmay advance from the second beam314bat the speed S3 that is less than the speed S1. As such, the first elastic strands316aand the second elastic strands316bare stretched in the machine direction MD when combined with the first and second substrates306,308. In addition, the speed S2 may be less than or greater than different than the speed S3. Thus, the first elastic strands316amay be stretched more or less than the second elastic strands316bwhen combined with the first and second substrates306,308. It is also appreciated that the first and second elastic strands316a,316bmay have various different material constructions and/or decitex values to create elastomeric laminates302having different stretch characteristics in different regions. In some configurations, the elastic laminate may have regions where the elastic strands316are spaced relatively close to one another in the cross direction CD and other regions where the elastic strands316are spaced relatively farther apart from each other in the cross direction CD to create different stretch characteristics in different regions. In some configurations, the elastic strands316may be supplied on the beam314in a stretched state, and as such, may not require additional stretching (or may require relatively less additional stretching) before being combined with the first substrate306and/or the second substrate308. Thus, in some configurations, the first elastic strands316amay be supplied on the first beam314aat a first tension, and the second elastic strands316bmay be supplied on the second beam314bat a second tension, wherein the first tension is not equal to the second tension.

In another configuration shown inFIG. 12, the second roller330may be positioned downstream from the first roller324. As such, the first roller324may be configured as the second metering device312and the second roller330may be configured as a third metering device366. As shown inFIG. 14, the first substrate306advances at speed S1 to the first roller324where the first substrate306partially wraps around the outer circumferential surface326of the first roller324and advances from the first roller to the second roller330to be combined with second substrate308. As the beam314rotates, the elastic strands316advance from the beam314at a speed S2 with the elastic strands316being spaced apart from each other in the cross direction CD. From the beam314, elastic strands316advance to the first roller324and are positioned on the second surface340of the first substrate306. In some configurations, the speed S2 is less than the speed S1, and as such, the elastic strands316are stretched in the machine direction MD. With continued reference toFIG. 12, the first substrate306and the elastic strands316advance from the outer circumferential surface326of the first roller324to the second roller330. In addition, the second substrate308advances at speed S1 to the second roller330where the second substrate308partially wraps around the outer circumferential surface332of the second roller330. In turn, the combined first substrate306and the stretched elastic strands316advance from first roller324to the second roller330and are combined with the second substrate308such that the elastic strands316are joined with the second surface340of the first substrate306and the first surface342of the second substrate308to produce a continuous length of elastomeric laminate302.

In another configuration shown inFIG. 13, the apparatus300may be configured with only the first roller324and without a second roller330. As such, the first roller324may be configured as the second metering device312. In addition, the first roller324may also be configured as a component of the bond applicator500. As shown inFIG. 13, the first substrate306advances at speed S1 to the first roller324where the first substrate306partially wraps around the outer circumferential surface326of the first roller324. While partially wrapped around the outer circumferential surface326of the first roller324, the first substrate306is combined with the elastic strands316and the second substrate308. As the beam314rotates, the elastic strands316advance from the beam314at a speed S2 with the elastic strands316being spaced apart from each other in the cross direction CD. From the beam314, elastic strands316advance to the first roller324and are positioned on the second surface340of the first substrate306. In some configurations, the speed S2 is less than the speed S1, and as such, the elastic strands316are stretched in the machine direction MD. With continued reference toFIG. 13, the second substrate308advances at speed S1 to the first roller324and partially wraps around the outer circumferential surface326of the first roller324. In turn, the second substrate308is combined with the first substrate306and the stretched elastic strands316while on the first roller324such that the elastic strands316are joined with the second surface340of the first substrate306and the first surface342of the second substrate308to produce a continuous length of elastomeric laminate302. In addition, the bond applicator500may be configured to apply the bonds322before elastic laminate302advances from the first roller324.

In some configurations, the speed S2 is less than the speed S1, and as such, the elastic strands316are stretched in the machine direction MD. With continued reference toFIG. 13, the second substrate308advances at speed S1 to the first roller324and partially wraps around the outer circumferential surface326of the first roller324. In turn, the second substrate308is combined with the first substrate306and the stretched elastic strands316while on the first roller324such that the elastic strands316are joined with the second surface340of the first substrate306and the first surface342of the second substrate308to produce a continuous length of elastomeric laminate302. In addition, the bond applicator500may be configured to apply the bonds322before elastic laminate302advances from the first roller324.

It is also to be appreciated that in some configurations, the first substrate and second substrate306,308herein may be defined by two discrete substrates or may be defined by folded portions of a single substrate. For example, as shown inFIG. 14, the first substrate306advances at speed S1 to the first roller324where the first substrate306partially wraps around the outer circumferential surface326of the first roller324. While partially wrapped around the outer circumferential surface326of the first roller324, the first substrate306is combined with the elastic strands316. As the beam314rotates, the elastic strands316advance from the beam314at a speed S2 with the elastic strands316being spaced apart from each other in the cross direction CD. From the beam314, elastic strands316advance to the first roller324and are positioned on the second surface340of the first substrate306. As shown inFIGS. 14 and 15, a folding device368may operate to fold a first portion306aonto a second portion306bof the first substrate with the elastic strands316positioned between the first and second portions306a,306bto create the elastic laminate302. As shown inFIGS. 14 and 16, the bond applicator500may be configured to apply the bonds322before elastic laminate302advances from the first roller324.

As illustrated herein, the apparatuses and processes may be configured such that elastic strands may be advanced from the beams and directly to the assembly process without having to touch additional machine components, such as for example, guide rollers. It is also to be appreciated that in some configurations, elastic strands may be advanced from beams and may be redirected and/or otherwise touched by and/or redirected before advancing to the assembly process. For example,FIG. 17shows a configuration where the beam rotation axis346may extend in a first cross direction CD1. As the beam314rotates, the elastic strands316advance from the beam314in a first machine direction MD1 with the elastic strands316being spaced apart from each other in the first cross direction CD1. The elastic strands316may then be redirected by rollers323from the first machine direction MD1 to a second machine direction MD2, wherein the elastic strands316may remain separated from each other in a second cross direction CD2. From the rollers323, the elastic strands316may advance in the second machine direction MD2 to be combined with the first and second substrates306,308to form the elastomeric laminate302. Thus, it is to be appreciated that the beam314may be arranged and/or oriented such that the beam rotation axis346may be parallel, perpendicular, or otherwise angularly offset with respect to the machine direction advancement of the elastomeric laminate302and/or the substrates306,308.

It is to be appreciated that the bonding methods and apparatuses herein may be utilized in conjunction with other bonding methods and apparatuses and/or assemble various types of laminates and absorbent articles, such as disclosed in U.S. Patent Application No. 62/686,896, filed on Jun. 19, 2018; 62/687,031, filed on Jun. 19, 2018; 62/685,429, filed on Jun. 15, 2018; 62/581,278, filed on Nov. 3, 2017; 62/553,149, filed on Sep. 1, 2017; 62/553,538, filed on Sep. 1, 2017; and 62/553,171, filed on Sep. 1, 2017, and U.S. Patent Publication Nos. 2018/0168880A1; 2018/0170027A1; 2018/0169964A1; 2018/0168879A1; 2018/0170026A1; 2018/0168889A1; 2018/0168874A1; 2018/0168875A1; 2018/0168890A1; 2018/0168887A1; 2018/0168892A1; 2018/0168876A1; and 2018/0168891A1, the entireties of which are all incorporated by reference herein.