ABSORBENT CORE HAVING CHANNELS AND ABSORBENT ARTICLE COMPRISING THE ABSORBENT CORE

Abstract

An absorbent core 21 having a length in a longitudinal direction L and a width in a transverse direction T, the absorbent core 21 including an upper core cover layer 24 and a lower core cover layer 25 with an absorbent material 70 therebetween, and including a pair of longitudinally extending channels 35, 36 in the absorbent material 70, the channels 35, 36 being substantially free of absorbent material and having channel seals 37, 38, the channel seals 37, 38 defining the upper and lower core cover layers 24, 25 within the channels 35, 36. , 25 are joined together, with respect to a transverse segment of the absorbent core 21, one of the upper and lower core cover layers 24, 25 having a first width W1 between the channel seals 37, 38 and the other of the core cover layers 24, 25 having a second width W2 between the channel seals 37, 38, the first and second widths W1, W2 of the core cover layers 24, 25 being the widths of the core cover layers 24, 25 between the channel seals 37, 38 in the deployed state, and the first width W1 being at least 120% of the second width W2.

Description

[Technical field]

[0001] The present disclosure relates to an absorbent core comprising an upper core cover layer and a lower core cover layer, and an absorbent material sandwiched between the upper and lower core cover layers. The absorbent article comprises a pair of channels in the absorbent material, each of the channels having a channel seal extending therein, the channel seal joining the upper and lower core cover layers within the channels. The present disclosure further relates to an absorbent article comprising the absorbent core. [Background technology]

[0002] In disposable absorbent articles, such as baby diapers and other articles for absorbing body fluids, such as pant-type absorbent garments, incontinence protectors, and sanitary napkins, there is a clash between the requirements for sufficient absorption capacity and leakage prevention and the comfort and discretion of the wearer. Thus, there is a demand for highly absorbent articles that are flexible without being bulky and that fit well to the wearer's body. It is highly desirable that the wearer does not feel restricted or uncomfortable when wearing the absorbent article, and yet can be sure that the article is efficient in preventing leakage. For adult users, it is particularly important that the pant-type garment resembles normal underwear as much as possible and can be worn unnoticeably under normal tight-fitting clothing. In order to provide a sufficient absorption capacity while being a thin absorbent article, the majority of the absorbent material can be superabsorbent material, or simply what is commonly known as "superabsorbent". Superabsorbents can be combined with absorbent fibers (mainly cellulose pulp fibers) to generate a fibrous network that contributes to distributing liquids in the absorbent core and to keeping particulate superabsorbent materials in the core. Superabsorbents are polymeric materials that are usually incorporated into absorbent articles in the form of fibers, particles, or granules. When they swell to form a hydrogel, they can absorb many times their own weight in fluid. It has been found that absorbent articles containing large amounts of superabsorbent materials lose their initial flexibility and wearer comfort when they absorb liquid and swell. High-impact areas of absorbent articles (such as the crotch area of ​​a diaper, which contains a large amount of absorbent material distributed over a relatively small area) can thicken and become stiff as the article absorbs liquid. Moreover, in order to keep material consumption to a minimum when producing absorbent articles, it is important in disposable absorbent articles that the available absorption capacity of the absorbent material can be fully utilized as much as possible. It is therefore desirable that the entire absorbent capacity of a superabsorbent material can be utilized.It has been proposed to provide further stabilization of the absorbent core in absorbent cores having a high content of superabsorbent material (e.g., 50% or more superabsorbent material) and a relatively low amount of cellulose pulp fibers or no cellulose fibers.

[0003] In the patent application WO 2005 / 023363, it is proposed to stabilize the absorbent core and counter sagging in the crotch area of ​​the absorbent article by forming two longitudinally extending channel sealings in the absorbent core. The absorbent core is enclosed in a core cover, and the channel sealings join the upper side of the core cover with the lower side of the core cover and are arranged such that they divide the absorbent core into a central segment and two side segments. When the absorbent material in the absorbent core absorbs body fluids and swells, the core cover acts as a swelling limiting means by limiting the swelling space for the absorbent material in the different segments. The expanding absorbent material thereby exerts an outward pressure on the core cover, resulting in an increase in the stiffness of the absorbent core in the crotch area of ​​the absorbent article. In particular, a high stiffness can thereby be realized in the central segment of the absorbent core between the two channel sealings. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2019 / 125231 Brochure [Patent Document 2] International application number PCT / EP2022 / 054991 Summary of the Invention [Means for solving the problem]

[0005] The present disclosure is based on the insight that an absorbent article with improved fit, body adaptability and wearer comfort as well as good absorbency and leakage protection can be at least partly realized by the features of claim 1 or, alternatively, by the features of claim 10. Variations of the disclosure are set out in the dependent claims and in the following description.

[0006] The absorbent articles referred to herein can be, for example, wearable disposable absorbent articles in the form of open diapers, pant diapers, belt diapers, incontinence garments, and feminine hygiene garments, as well as disposable absorbent inserts, such as incontinence shields or sanitary napkins, that are worn inside a support garment (such as, for example, support pants or regular underwear). Such articles are used to absorb, distribute, and store various types of body exudates while providing the wearer with a high level of comfort and dryness during wear.

[0007] In a first aspect, the disclosure relates to an absorbent core having a length in a longitudinal direction and a width in a transverse direction perpendicular to the longitudinal direction. The absorbent core includes an upper core cover layer and a lower core cover layer, and an absorbent material sandwiched between the upper and lower core cover layers. The absorbent core includes a pair of channels extending longitudinally in the absorbent material. Each of the channels is free or substantially free of absorbent material and has a channel seal extending therein, the channel seal joining the upper and lower core cover layers in the channel and extending along the longitudinal channel seal length. The absorbent core is divided along the channel seal length into one or more bordering imaginary sets of transverse segments, each transverse segment having a segment length of 10 mm and including a channel seal. The set includes the maximum number of segments possible along the channel seal length. The absorbent core further comprises, for at least one transverse segment of said set of segments, one of the lower core cover layer and the upper core cover layer has a first width between the channel seals and the other of the lower core cover layer and the upper core cover layer has a second width between the channel seals, the first width being greater than or equal to 120% of the second width, the first and second widths of the core cover layer being the width of the core cover layer between the channel seals in a deployed, fully flat state.

[0008] During use of an absorbent article including an absorbent core as described above, the absorbent material of the absorbent core will absorb body fluids and swell. The channel seals joining the upper and lower core cover layers in the channels will act as a restriction means, which restricts the swelling of the absorbent material in the transverse direction and in the thickness direction by preventing the upper and lower core cover layers from moving freely apart from each other. However, by having one of the upper and lower core cover layers have a first width between the channel seals and the other of the upper and lower core cover layers have a second width between the channel seals, the first width being greater than the second width, additional space is provided between the channel seals for swelling of the parts of the absorbent material trapped between the channel seals and between the upper and lower core cover layers. Thus, the absorbent core is provided with an improved swelling capacity, thereby improving the utilization of the absorption capacity of the absorbent material.

[0009] The channel seals prevent separation of the upper and lower core cover layers, thereby limiting swelling of the absorbent material in the vicinity of the channels. The channel seals are preferably permanent seals, or at least a majority of each channel seal is a permanent seal that does not break under normal use and handling of the absorbent article. For example, the channel seals can be adhesive seals, weld seals, or a combination of adhesive seals and weld seals.

[0010] The seal strength of the channel seal can be, for example, 2.5 N / 25 millimeters or greater, such as 3 N / 25 millimeters or greater, when measured according to the test methods disclosed herein. There is no upper limit for the seal strength of the channel seal, as the only requirement for the channel seal is that it not rupture under pressures that may be exerted on the seal during normal use.

[0011] It should be understood that, prior to the present invention, in an absorbent core provided with channels having channel seals, the widths of the upper and lower core cover layers between the channel seals are substantially equal. Thus, by providing a core cover with a first width between the channels on one side of the core cover layer and a second width between the channels on the other side of the core cover layer that is different from the first width, improved utilization of the absorbent material's absorption capacity can be achieved without increasing the width between the channel seals of the absorbent core (as seen in the dry state of the absorbent core). The increased space for absorbent material provided between the channel seals and bounded by the core cover layers provides improved swelling capacity, mainly in the thickness direction of the absorbent core.

[0012] Thus, an absorbent core with improved utilization of absorbent capacity can be achieved without increasing the width of the absorbent core (the mutual width of the upper and lower core cover layers), which is beneficial for the comfort and fit of absorbent articles that include the absorbent core.

[0013] The first width should be greater than or equal to 120% of the second width.

[0014] Optionally, in at least one of the transverse segments, the first width can be 130% or more of the second width. For example, the first width can be 135% or more of the second width. For example, the first width can be in a range of 120% to 160% of the second width, such as in a range of 130% to 160% or 135% to 160% of the second width.

[0015] Optionally, in at least one said transverse segment, the first width differs from the second width by 3 mm or more, such as by 5 mm or more or 7 mm or more.

[0016] Optionally, in at least one of the transverse segments, the third width as measured between the channel seals of the absorbent core is between 20 mm and 60 mm. For example, the third width can be between 25 mm and 45 mm.

[0017] The third width should be measured as it is on the absorbent core in a dry state prior to use (in other words, the third width should not be measured in an unfolded state like the first and second widths).

[0018] The absorbent material in at least one of the transverse segments has an absorbent width, such that the absorbent width can be measured from a first side edge to a second side edge of the absorbent material in the absorbent core.

[0019] In at least one of said transverse segments, the upper core cover layer and the lower core cover layer extend across one another's width, which is the core width as defined herein.

[0020] As such, the first longitudinal side edge and the second longitudinal side edge of the absorbent core are considered to be the longitudinal side edges which bound the mutual width of the upper and lower core cover layers.

[0021] In some instances, in at least one said transverse segment, the upper core cover layer and the lower core cover layer can have the same width, in which case this width is the core width.

[0022] In other examples, in at least one of said transverse segments, the upper core cover layer and the lower core cover layer can have different widths, in which case the extension of these different widths to one another constitutes the core width as defined herein.

[0023] The absorbent width may be less than the core width in at least one said transverse segment, so that the upper and lower core cover layers have a mutual extension across the entire absorbent width and surround the absorbent material.

[0024] Optionally, in at least one of said segments, the absorber width may be substantially equal to the core width.

[0025] Because the first width is greater than the second width, allowing for increased expansion of the absorbent material between the channel joints in the thickness direction of the absorbent core, the core width can be selected to be relatively close to the absorbent width while still providing an absorbent core with improved swelling capacity.

[0026] For example, in at least one of said segments, the absorber width can be greater than or equal to 90% of the core width, such as between 90% and 100% of the core width, for example, the absorber width can be between 95% and 100% of the core width.

[0027] As noted above, the absorbent core has a third width in at least one of said segments, the third width being measured between the channel seals of the absorbent core.

[0028] For example, the third width can be in the range of 15% to 40% of the absorber width, such as in the range of 20% to 35% of the absorber width.

[0029] Two of the pair of channels can be symmetrically spaced apart and extend on either side of a longitudinal centerline of the absorbent material, such that each channel can extend between the longitudinal centerline and a corresponding one of the first or second side edges of the absorbent material.

[0030] The channel can have different shapes. For example, the channel may be curved or the channel may be inclined relative to the longitudinal direction. However, regardless of its shape, the channel will have an extension along the longitudinal direction. Similarly, the channel seal will have a channel seal length when viewed along the longitudinal direction.

[0031] In some instances, two of the pair of channels are straight and extend parallel to the longitudinal direction.

[0032] In some cases, the absorbent core may include more than one pair of channels, each pair of channels may, for example, extend across a separate longitudinal portion of the absorbent core.

[0033] For example, the length of each of the channels of the pair of channels can range from 50 millimeters to 500 millimeters. For example, the channel seal length of each of the channel seals can range from 50 mm to 500 mm.

[0034] For example, the length of each of the channels can be 75 millimeters to 400 millimeters, 100 millimeters to 300 millimeters, or 150 millimeters to 200 millimeters. For example, the channel seal length of each of the channel seals can be 75 millimeters to 400 millimeters, 100 millimeters to 300 millimeters, or 150 millimeters to 200 millimeters.

[0035] The core cover layer can be made from a core cover material.

[0036] As used herein, the basis weight of a core cover material is, for example, 5 g / m 2 From 20g / m 2 It is possible that the range is

[0037] The core cover material can be made of a thermoplastic polymer material, such as polyolefins, polyesters, polyamides, and combinations thereof. The core cover material can be a nonwoven material, a perforated plastic film, a net, and the like. The nonwoven layer can be formed by any of a variety of different processes, such as a spunbond process, an airlaying process, a meltblown process, or a bonded carded web formation process, as known in the art. The nonwoven layer can be made of a co-formed lamina of a nonwoven material, such as an SMS (spunbond / meltblown / spunbond) nonwoven material, an SMMS nonwoven material (spunbond / meltblown / meltblown / spunbond), or an SS (spunbond / spunbond) nonwoven material. The thermoplastic polymer material in the nonwoven layer can be polypropylene, or a bicomponent fiber of polypropylene and polyethylene, or a combination of such materials.

[0038] For example, the upper and lower core cover layers can be constructed of a nonwoven material.

[0039] The absorbent material can include or consist of cellulose pulp fibers and superabsorbent materials.

[0040] The absorbent material may include a superabsorbent material, and preferably, between 5% and 80% by weight of the absorbent material is a superabsorbent material, for example, the absorbent material may include between 30% and 80% by weight of a superabsorbent material.

[0041] The absorbent material may comprise superabsorbent material, preferably in an amount of 5% to 80% by weight (such as, for example, 30% to 80% by weight) in at least the part of the absorbent core in which the pair of channels are located. Thus, the content of superabsorbent material may be lower, for example, in the front and / or rear end parts of the absorbent core than in the central part of the absorbent core comprising the pair of channels.

[0042] The absorbent material can be composed of one single absorbent component layer. Absorbent materials comprising two or more layers are also contemplated for the absorbent articles as disclosed herein.

[0043] The superabsorbent material can be a polymeric material and can be in the form of particles, granules fibers, flakes, and the like.

[0044] A relatively high amount of superabsorbent material in the absorbent core allows for the production of thin, discrete absorbent articles while providing high absorbent capacity and the ability to chemically bind absorbed fluids, resulting in an absorbent article with high leak-proofing and a dry inner surface even after absorbing large amounts of fluid. Thin, superabsorbent-containing articles also have pre-use advantages because they take up less space for packaging, shipping, and storage, as well as on store shelves.

[0045] For example, the absorbent material between the channel seals may have a basis weight in the range of 500 gsm to 1200 gsm.

[0046] Optionally, the first and second core cover layers are formed from a single continuous cover material that is wrapped around the absorbent material. When the core cover is formed from a single layer of material, the single layer of material can be wrapped around the absorbent core.

[0047] Optionally, the core cover can be formed by a separate upper core cover layer and a separate lower core cover layer.

[0048] The absorbent core can have any suitable shape in the plane defined by the longitudinal and transverse directions, for example, the absorbent core can have an hourglass shape or a T-shape in the plane defined by the longitudinal and transverse directions.

[0049] In another example, the absorbent core has a rectangular shape with longitudinally extending side edges and transversely extending end edges.

[0050] The absorbent core can include two or more parts with different absorbent capacities. The absorbent core can be a three-dimensional contoured core, with a central part of the absorbent core, when viewed in the longitudinal direction, disposed between a first end part of the absorbent core and a second end part of the absorbent core, the central part of the absorbent core having a thickness greater than the thickness of the first end part and greater than the thickness of the second end part.

[0051] The central part of the absorbent core can have a uniform first thickness, the first end part can have a uniform second thickness, and the second end part can have a uniform third thickness. The first thickness can be equal to the second thickness. The central part of the absorbent core can be separated from the first and second end parts, respectively, by corresponding first and second transition zones.

[0052] The first end part can be a front end part and the first transition zone can be a front transition zone having a longitudinal extension of 5 to 30 millimeters (such as for example 10 to 20 millimeters), and the second end part is a rear end part and the second transition zone is a rear transition zone having a longitudinal extension of 20 to 80 millimeters (such as for example 30 to 60 millimeters). The thickness of the absorbent core preferably varies linearly in the transition zone between the end part and the central part.

[0053] The ratio of the thickness of the central part of the absorbent core to the thickness of the first end part can be in the range of 4 to 1.5, and the ratio of the thickness of the central part of the absorbent core to the thickness of the second end part can be in the range of 4 to 1.5.

[0054] The end parts can have equal thickness. However, end parts with different thicknesses are also conceivable for an absorbent article as disclosed herein. The front end part can have a greater thickness than the rear end part.

[0055] The length of the absorbent core in an absorbent article as disclosed herein is determined as the distance between a point on a first end edge of the absorbent core where the first end edge intersects the longitudinal centerline and a point on a second end edge of the absorbent core where the second end edge intersects the longitudinal centerline, and the length of the absorbent core is in the range of 300 millimeters to 700 millimeters (e.g., in the range of 350 millimeters to 600 millimeters, or in the range of 400 millimeters to 500 millimeters, etc.).

[0056] In absorbent cores with a thickened central part, the thickened central part may have a length on the order of 30% to 70% of the length of the absorbent core (e.g., on the order of 40% to 60% of the length of the absorbent core, or on the order of 45% to 55% of the length of the absorbent core, etc.) The length of the thickened central part may be approximately half the length of the absorbent core.

[0057] The absorbent core in the absorbent article as disclosed herein can have any planar shape, such as, for example, a rectangular shape, a T-shape, or an hourglass shape. The hourglass shape includes all configurations of the core in which the end parts are wider than the central part. Planar shapes with the central part narrower than the end parts may be more suitable than rectangular shapes, because the narrow central part may fit more comfortably in the crotch of the wearer. Moreover, the narrow central part of the absorbent core may allow for a larger transverse expansion of the core during use of the absorbent article without causing discomfort.

[0058] The absorbent core as disclosed herein may include a three-dimensionally shaped core with a thicker central part and thinner end parts, surrounded by a core cover including an upper layer and a lower layer. The upper layer and the lower layer may be formed from a single web material or two web materials. The cover material may be a nonwoven material. The core has a pair of sealed channels disposed therein (e.g., two sealed channels symmetrically disposed on either side of a longitudinally extending centerline of the article, etc.). The upper and lower layers of the core cover are bonded to each other by a channel seal disposed in the channel. The upper and lower layers are in contact with each other at side regions extending along the side edges of the absorbent core. One or more channels are free of absorbent material, meaning that the upper and lower layers of the core cover are directly bonded to each other at the channel seal. The absorbent core may also be molded in a plane, for example having an hourglass shape with a central part of the absorbent core narrower than the first and second end parts.

[0059] In the three-dimensionally shaped absorbent core as disclosed herein, the thinner end parts can have a uniform or substantially uniform thickness and the thicker central part can have a uniform or substantially uniform thickness. A transition zone can be located between the thicker central part and the thinner end parts, and the thickness of the absorbent core preferably decreases linearly or substantially linearly from the central part to the end parts in the transition zone. The end parts can be designated front end parts and designated rear end parts, and the rear end parts have a greater extension in the longitudinal direction of the absorbent article than the front end parts. The rear transition zone can have a greater extension in the longitudinal direction of the absorbent article than the front transition zone, as disclosed herein.

[0060] The pair of channels can be at least partially (eg, completely, etc.) disposed within the central part of the absorbent core.

[0061] Optionally, in at least a portion of the absorbent core, the upper core cover layer and the lower core cover layer are connected at a first side seal in a first side region extending along a first side edge of the absorbent material and at a second side seal in a second side region extending along a second side edge of the absorbent material, said portion preferably including at least one of said transverse segments.

[0062] The side seals can be permanent seals, i.e., intended to be retained during use of the absorbent core. However, in an example, the seal strength of the channel seals of the absorbent core can be higher than the seal strength of each of the first and second side seals of the absorbent core. Thus, the first and second side seals can be breakable seals. The channel seals prevent separation of the upper and lower core cover layers, thereby limiting swelling in the thickness direction of the absorbent core in the vicinity of the channels. The channel seals are preferably permanent seals, or at least a majority of each channel seal is a permanent seal that does not break under normal use and handling of the absorbent article. A permanent seal resists forces resulting from the swelling absorbent material in the absorbent core and remains intact throughout the use of the absorbent article. The side seals are breakable seals that break under the influence of forces exerted on the side seals as the absorbent material in the absorbent core absorbs fluid and expands. The rupturable side seals, in conjunction with the channel seal, drive the expansion of the absorbent material primarily in the lateral or transverse direction of the absorbent core and absorbent article.

[0063] For example, the seal strength of each one of the channel seals can be 2.5 N / 25 millimeters or more (e.g., 3 N / 25 millimeters or more), and / or the seal strength of the first and second side seals can be 2.0 N / 25 millimeters or less (e.g., 1.5 N / 25 millimeters or less), when measured according to the test methods disclosed herein.

[0064] According to another example, in at least a portion of the absorbent core, the upper and lower core cover layers are free of seals to each other in the portion of the core extending transversely beyond the first channel seal to the first side edge of the absorbent core and in the portion of the core extending transversely beyond the second channel seal to the second side edge of the absorbent core. Thus, in this example, the absorbent core lacks a seal connecting the upper and lower core cover layers in a first side region extending along the first side edge of the absorbent material and in a second side region extending along the second side edge of the absorbent material. The portion of the absorbent core preferably includes at least one said transverse segment.

[0065] As will be further explained below with respect to absorbent articles including such absorbent cores, the lack of seals between the upper and lower core cover layers at the outer side edges of the absorbent material allows swelling of the absorbent material in the respective transverse directions outside the core width, thus further improving utilization of the absorbent capacity of the absorbent material.

[0066] Thus, an absorbent core as disclosed herein can include an upper core cover layer and a lower core cover layer that sandwich an absorbent material. The core can include a pair of sealed channels disposed therein (e.g., two sealed channels symmetrically disposed on either side of a longitudinally extending centerline of the article, etc.). The upper and lower layers of the core cover are bonded to one another by a channel seal, which is disposed in one or more channels and extends along a longitudinal channel seal length. The pair of channels is free of absorbent material, meaning that the upper and lower layers of the core cover are bonded directly to one another at the channel seal. The absorbent core is divided into an imaginary set of one or more adjacent transverse segments along the channel seal length, each transverse segment having a segment length of 10 mm and including a channel seal. The set includes the maximum number of adjacent segments possible along the channel seal length.

[0067] The absorbent core has, for at least one transverse segment of said set of segments, one of the lower core cover layer and the upper core cover layer having a first width between the channel seals and the other of the lower core cover layer and the upper core cover layer having a second width between the channel seals, the first and second widths of the core cover layer being the width of the core cover layer between the channel seals in the fully flat unfolded state, the first width being 120% or more of the second width. The second width being greater than the first width means that a space is provided for the expansion of the absorbent material located transversely between the channels, allowing the expansion of the absorbent material between the channels mainly in the thickness direction of the absorbent core. The absorbent core can also be molded in a plane, for example having an hourglass shape with the central part of the absorbent core being narrower than the first and second end parts. Optionally, the upper and lower core cover layers may be free of seals to each other in the portion of the core extending transversely beyond the first channel seal toward the first side edge and in the portion of the core extending transversely beyond the second channel seal toward the second side edge. The absence of seals between the upper and lower core cover layers to each other in said portions means that the absorbent material located transversely outside the pair of channels on each side of the absorbent core may extend in each transverse direction without being restricted by such seals. For example, the absorbent material may expand transversely beyond the mutual extension of the upper and lower core cover layers. For example, the at least one transverse segment may include at least one quarter of one or more segments in the set of segments, or at least half of one or more segments in the set of segments. For example, the at least one transverse segment may include all of the segments in the set of segments.

[0068] The absorbent core as disclosed herein may include a three-dimensionally shaped core material with a thicker central part and thinner end parts, the core material being sandwiched between an upper core cover layer and a lower core cover layer. The cover material may be a nonwoven material. The core includes a pair of sealed channels disposed therein and extending along a longitudinal channel seal length (e.g., two sealed channels symmetrically disposed on either side of the longitudinally extending centerline of the article, etc.). The upper and lower layers of the core cover are bonded to each other by a channel seal disposed in one or more of the channels. The pair of channels is free of absorbent material, meaning that the upper and lower layers of the core cover are directly bonded to each other at the channel seal. The absorbent core is divided into an imaginary set of one or more adjacent transverse segments along the channel seal length, each transverse segment having a segment length of 10 mm and including a channel seal. The set includes the maximum number of adjacent segments possible along the channel seal length. The absorbent core has, for at least one transverse segment of said set of segments, one of the lower core cover layer and the upper core cover layer has a first width between the channel seals and the other of the lower core cover layer and the upper core cover layer has a second width between the channel seals, the first and second widths of the core cover layer being the width of the core cover layer between the channel seals in a fully flat, unfolded state, and the first width being 120% or more of the second width. For example, the at least one transverse segment can include at least one quarter of one or more segments in the set of segments or at least half of one or more segments in the set of segments. For example, the at least one transverse segment can include all of the segments in the set of segments.The second width being greater than the first width means that a space is provided for the expansion of the absorbent material located transversely between the channels, allowing the expansion of the absorbent material between the channels mainly in the thickness direction of the absorbent core. The absorbent core can also be molded in a plane, for example having an hourglass shape with the central part of the absorbent core narrower than the first and second end parts. Optionally, the upper and lower core cover layers can be free of seals to each other in the part of the core extending transversely beyond the first channel seal towards the first side edge and in the part of the core extending transversely beyond the second channel seal towards the second side edge. The absence of seals of the upper and lower core cover layers to each other in said parts means that the absorbent material located transversely outside the pair of channels on each side of the absorbent core can extend in the respective transverse direction without being restricted by such seals. For example, the absorbent material may expand transversely beyond the mutual extension of the upper and lower core cover layers.

[0069] In the three-dimensionally shaped absorbent core as disclosed herein, the thinner end parts can have a uniform or substantially uniform thickness and the thicker central part can have a uniform or substantially uniform thickness. A transition zone can be located between the thicker central part and the thinner end parts, and the thickness of the absorbent core preferably decreases linearly or substantially linearly from the central part to the end parts in the transition zone. The end parts can be designated front end parts and designated rear end parts, and the rear end parts have a greater extension in the longitudinal direction of the absorbent article than the front end parts. The rear transition zone can have a greater extension in the longitudinal direction of the absorbent article than the front transition zone, as disclosed herein.

[0070] In a second aspect, there is provided an absorbent article comprising an absorbent core according to the first aspect.

[0071] The absorbent article may include, in at least a portion of the absorbent article, a first edge seal extending along and immediately adjacent a first side edge of the absorbent material and a second edge seal extending along and immediately adjacent a second side edge of the absorbent material. The portion of the absorbent article may preferably include at least one of said segments.

[0072] By "directly adjacent" it is meant that there are no other seals between the first or second side edge of the absorbent material and the first or second edge seal, respectively. Thus, the first or second edge seal, respectively, will be the first seal that the absorbent material can reach when expanding in the transverse direction. Thus, the first and second edge seals form seals that limit the transverse expansion of the absorbent material at its first and second side edges.

[0073] For example, if the sealed width is the transverse distance between a first edge seal and a second edge seal and the upper and lower core cover layers of an absorbent core extend across their mutual width, which is the core width, the sealed width can be greater than the core width.

[0074] As already described above, the upper and lower core cover layers extend across a mutual width, which is the core width as defined herein. In some examples, the upper and lower core cover layers can have the same width, in which case this width is the core width. In other examples, the upper and lower core cover layers can have different widths, in which case the mutual extension of these different widths constitutes the core width as defined herein.

[0075] Thus, the sealed width being greater than the core width means that the first and second edge seals extend outside the core width (i.e., outside the core). In other words, the seals that limit the transverse expansion of the absorbent material are positioned outside the core width in the transverse direction. Thus, the absorbent material is able to expand outside the core width in the transverse direction. Thus, the absorbent article provides additional space for swelling of the absorbent material beyond the limited core width.

[0076] Advantageously, in the absorbent article, the absorbent core can be such that in the portion of the core extending transversely beyond the first channel seal towards the first side edge of the absorbent core, and in the portion of the core extending transversely beyond the second channel seal towards the second side edge of the absorbent core, the upper core cover layer and the lower core cover layer are free of seals to each other, as described above. Thus, in this example, the absorbent core lacks side seals connecting the upper core cover layer and the lower core cover layer, and thus the first and second edge seals extend directly adjacent to the first and second side edges of the absorbent material, respectively.

[0077] The lack of side seals in the absorbent core further means that there may be some connection (albeit with very low integrity) between the upper and lower core cover layers in the first and second side regions, for example, the upper and lower core cover layers may be held together by mere frictional forces in the portions of the core cover that extend laterally beyond the absorbent core.

[0078] The absorbent article may include one or more additional upper layers above the upper core cover layer and / or may include one or more additional lower layers below the lower core cover layer.

[0079] For example, the first and second edge seals can be bonded between one of the additional upper layers and one of the additional lower layers.

[0080] For example, first and second edge seals may be bonded between one of the additional overlying layers and the lower core cover layer.

[0081] For example, first and second edge seals are bonded between one of the additional lower layers and the upper core cover layer.

[0082] For example, one of the additional upper layers can include a liquid-permeable topsheet. The first and second edge seals can be bonded between the topsheet and the lower core-cover layer. In another example, the first and second edge seals can be bonded between the topsheet and one of the additional lower layers.

[0083] For example, one of the additional lower layers can include a liquid barrier layer. The first and second edge seals can be bonded between the liquid barrier layer and the upper core cover layer. In another example, the first and second edge seals can be bonded between the liquid barrier layer and one of the additional upper layers.

[0084] For example, the first and second edge seals can be bonded between the topsheet and the liquid barrier layer.

[0085] As noted above, the first and second edge seals can be permanent seals, i.e., the seal strength of the first and second edge seals is such that it will not rupture under pressures that may be exerted on the seals during normal use. As such, there is no upper limit for the seal strength of the edge seals.

[0086] As noted above, the channel seal also provides a permanent seal, but the seal strength of the channel seal does not necessarily have to be the same as the seal strength of the edge seals, since the pressure exerted on the channel seal during use can be greater than the pressure exerted on the first and second edge seals.

[0087] For example, the seal strength of the channel seal can be equal to or greater than 2.5 N / 25 millimeters, as exemplified above.

[0088] The seal strength of the edge seal may in some variations be 2.5 N / 25 mm or greater as well, but in other variations the seal strength of the edge seal may be 1 N / 25 mm or greater.

[0089] For example, the edge seals and channel seals can be adhesive seals, weld seals, or a combination of adhesive seals and weld seals. The seals can be formed as a continuous bond line or can be formed by individual bond elements located along the seal.

[0090] Welded seals can include heat welded seals and other welded seals (e.g., ultrasonically welded seals, etc.) For welded seals (e.g., heat welded seals and ultrasonically welded seals, etc.), the seal strength can be controlled by varying parameters (e.g., sealing temperature, energy supply, sealing time, sealing pressure, etc.) and / or by varying the seal pattern.

[0091] For example, the first edge seal, the second edge seal, and each channel seal can be an adhesive seal.

[0092] In an example, the edge seals can be adhesive seals, with the basis weight of the adhesive in each edge seal being 2 g / m2 or more (for example, 3 g / m 2 or more than 5g / m 2 The above is possible.

[0093] In the absorbent article as disclosed herein, the absorbent article can include a liquid permeable topsheet and a liquid barrier layer, and the absorbent core is disposed between the liquid permeable topsheet and the liquid barrier layer. The liquid permeable topsheet and the liquid barrier layer are provided in addition to the upper and lower core cover layers. For example, the upper core cover layer can face the liquid permeable topsheet, and the lower core cover layer can face the liquid barrier layer.

[0094] The absorbent core with the liquid permeable topsheet, liquid barrier layer, and core cover may be part of or constitute an absorbent assembly or "core pack" that is produced as a separate unit and then attached to the front and back panels of an open-type or pant-type wearable article, or to the outer cover of an open-type or pant-type wearable article.

[0095] As explained above, an article comprising an absorbent core combination, in at least one segment, one of the lower core cover layer and the upper core cover layer has a first width between the channel seals, and the other of the lower core cover layer and the upper core cover layer has a second width between the channel seals, the first and second widths of the core cover layer being the width of the core cover layer between the channel seals in an unfolded, fully flat state, the first width being 120% or more of the second width, the sealed width being the transverse distance between the first edge seal and the second edge seal, the upper core cover layer and the lower core cover layer of the absorbent core extending across a mutual width that is the core width, the sealed width being greater than the core width, the article providing additional space for swelling of the absorbent material across a predetermined core width. Preferably, the article is capable of being such that the sealed width is greater than the core width across at least a portion of the article, including at least one of said segments.

[0096] Thus, additional space is provided between the pair of channels to allow swelling of the absorbent material primarily in the thickness direction, and additional space is provided in the parts of the absorbent material located transversely outward of the pair of channels to allow swelling of the absorbent material primarily in the transverse direction, thus improving utilization of the absorbent capacity of the absorbent material in the article.

[0097] However, the benefits of providing additional space for swelling of the absorbent material positioned transversely outward of a pair of channels can also be achieved without simultaneously providing additional space for swelling of the absorbent material in the thickness direction between the pair of channels.

[0098] Thus, in an alternative aspect, an absorbent article is provided that includes an absorbent core, the absorbent core having a length in a longitudinal direction and a width in a transverse direction perpendicular to the longitudinal direction. The absorbent core includes upper and lower core cover layers, an absorbent material sandwiched between the upper and lower core cover layers, and a pair of channels extending longitudinally in the absorbent material. Each of the one or more channels is free or substantially free of absorbent material and has a channel seal extending therein. The channel seal joins the upper and lower core cover layers in the channel and extends along the longitudinal channel seal length. The absorbent core is divided along the channel seal length into one or more imaginary sets of adjacent transverse segments, each transverse segment having a segment length of 10 mm and including a channel seal. The set includes the maximum number of adjacent segments possible along the channel seal length. In at least some of the absorbent articles, the absorbent core comprises at least one segment from the set of segments, the absorbent article comprises a first edge seal and a second edge seal, the first edge seal extending along and directly adjacent to a first side edge of the absorbent material and the second edge seal extending along and directly adjacent to a second side edge of the absorbent material, the sealed width being the transverse distance between the first edge seal and the second edge seal, and the upper core cover layer and the lower core cover layer of the absorbent core extend across a mutual width that is the core width, such that the sealed width is greater than the core width.

[0099] Thus, similar to that described above, in the absorbent article according to the alternative embodiment, the sealed width is greater than the core width, which means that the first and second edge seals extend outside the core width (i.e., outside the core). In other words, the seals that limit the transverse expansion of the absorbent material are positioned outside the core width in the transverse direction. Thus, the absorbent material is able to expand outside the core width in the transverse direction. Thus, the absorbent article provides additional space for swelling of the absorbent material beyond the limited core width.

[0100] The absorbent article according to the alternative embodiment may be combined with any one of the features as described above with respect to the absorbent article of the second embodiment or with respect to the absorbent core of the first embodiment to provide the same benefits.

[0101] The absorbent core and / or absorbent article as disclosed herein can be varied within the scope of the appended claims. For example, the materials and dimensions used for the different layers forming the absorbent core and / or absorbent article as disclosed herein can be varied as indicated above. The absorbent article can further include any useful components or features as known in the art, such as fluid acquisition and distribution components, leg elastics, standing gathers, crotch and waist elastics, side panels, fastening systems, wetness indicators, skin care agents, disposal means, etc. as known in the art and depending on the type of absorbent article intended.

[0102] As described above, some of the features are described as being applicable to at least one transverse segment of a set of segments that includes a channel seal. Some of the features are described as being applicable to at least one portion of an article that includes at least one transverse segment of a set of segments that includes a channel seal.

[0103] Optionally, any such feature may be applicable to at least a quarter of the segments in the set of segments, i.e., the at least one transverse segment includes at least a quarter of the segments in the set of segments.

[0104] Optionally, any such feature may be applicable to at least half of the segments in the set of segments, i.e., the at least one transverse segment includes at least half of the segments in the set of segments.

[0105] Optionally, any such feature may be applicable to all of the segments in the set of segments, ie, the at least one transverse segment includes all of the segments in the set of segments.

[0106] As described above, a set of segments can include one or more transverse segments. It will be understood that the number of segments in a set will depend on the longitudinal channel seal length (i.e., the length of the channel seal). Thus, the number of segments in a set will correspond to the longitudinal channel seal length divided by 10 mm, rounded down to the nearest integer.

[0107] For example, the set of segments can include at least two transverse segments or at least three transverse segments. For example, the set of segments can include at least five transverse segments or at least seven transverse segments.

[0108] By the term "width" as used herein is meant the maximum width as measured in the cross direction of the absorbent core or article.

[0109] By the term "length" as used herein is meant the maximum length as measured in the longitudinal direction of the absorbent core or article.

[0110] Unless expressly stated otherwise, width and length should be measured on the absorbent core or article as it is provided prior to wearer use.

[0111] By the term "through-thickness" is meant the transverse direction and the direction perpendicular to the longitudinal direction.

[0112] By the terms "upper" and "lower" as used herein, we mean two opposing directions along the thickness dimension (i.e., perpendicular to the transverse and longitudinal directions). Thus, such terms do not imply any particular orientation in the vertical direction. Moreover, such terms do not imply that the absorbent core or article should have any particular orientation relative to the user when in use. [Brief description of the drawings]

[0113] [Figure 1] FIG. 2 is a plan view of a stretched absorbent pant-type article with an absorbent assembly and open side seams as viewed from the inner surface of the pant-type article. [Diagram 2]2 is an enlarged view of the absorbent assembly in the pant-type article of FIG. 1, with the absorbent material enclosed within a core cover. [Figure 3a] FIG. 3 shows a cross section through a version of the absorbent core of FIG. 2 taken along line III-III when the absorbent core is in a dry state. [Figure 3b] FIG. 2 shows a cross section through another version of an absorbent core. [Figure 4a] 3 shows a cross section through the absorbent assembly of FIG. 2 taken along line III-III when the absorbent core is in a dry state. [Figure 4b] 3 shows a cross section through the absorbent assembly of FIG. 2 taken along line III-III when the absorbent core is in a wet state. [Diagram 5] 3 shows a cross section through another variant of the absorbent assembly of FIG. 2 taken along line III-III when the absorbent core is in a dry state. [Figure 6] FIG. 2 shows the pant-type article of FIG. 1 in a condition with the side seams closed and unstretched, as the pant-type article would appear prior to use. [Figure 7] FIG. 2 illustrates how a test specimen is mounted in the clamps of a test fixture to perform the seal strength test method as described herein. [Figure 8] FIG. 2 illustrates how a test specimen is mounted in the clamps of a test fixture to perform the seal strength test method as described herein. [Figure 9] FIG. 2 illustrates portions of a first core cover layer and a second core cover layer when in a deployed state. [Figure 10] FIG. 13 shows how the test specimen is mounted to perform width measurements in the deployed state. [Figure 11] FIG. 1 is a schematic diagram of the method as disclosed herein. [Figure 12]FIG. 2 is a top view of a first core cover web being applied to a mat-forming surface in a prior art method. [Figure 13] FIG. 13 is a cross-section through the first core cover web and mat-forming surface of FIG. 12 taken along line III-III. [Figure 14] FIG. 2 is a top view of a first core cover web being applied to a mat-forming surface in the method as disclosed herein. [Figure 15] FIG. 15 shows a cross section through the first core cover web and mat-forming surface of FIG. 14 taken along line VV. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0114] The different aspects of the present disclosure will be described more fully hereinafter with reference to the attached drawings. The embodiments disclosed herein can be realized in many different forms and should not be construed as being limited to the aspects described herein. Although the absorbent article shown in the figures is a pant-type article, it should be understood that the absorbent core as described in the examples, as disclosed herein, can be used in any disposable absorbent article for absorbing urine, feces, and / or vaginal secretions.

[0115] The drawings are schematic and individual elements (eg layers of material, etc.) are not necessarily drawn to scale.

[0116] The pant-type article shown in the figures is a simplified article and the article can contain additional features (e.g., barrier cuffs, etc.). It should also be understood that the waist elastics disclosed herein are optional or any other suitable type of waist elastic can be used. The side seams can be reclosable side seams and the pant-type article can be provided with fastener elements to provide reclosability of the side seams.

[0117] Referring initially to Figure 1, a pant-type article 1 is shown in the form of a pant-type incontinence article for an adult user. The pant-type article 1 is shown in Figure 1 in an unfolded flat condition, with all elastic elements in a fully extended state. The pant-type article has a longitudinal direction L and a transverse direction T, the transverse direction T being perpendicular to the longitudinal direction, with a longitudinal centreline Lc extending in the longitudinal direction L.

[0118] The pant-type article 1 is seen from its inner surface, which is the surface that will face the wearer's body when the article is worn, and which is opposite the outer garment-facing surface of the pant-type article 1.

[0119] The pant-type article 1 includes a front portion 3, a rear portion 4, and an absorbent assembly 20, which is positioned in the crotch portion 6 of the pant-type article 1 and extends forward over the front portion 3 and rearward over the rear portion 4 in the longitudinal direction L. The absorbent assembly 20 extends in the longitudinal direction L from the front portion 3 through the crotch portion 6 into the rear portion 4. The absorbent assembly 20 in the pant-type article shown in the figures is a separately manufactured component that includes an absorbent core 21, which includes an absorbent material 70 sandwiched between an upper core cover layer 24 and a lower core cover layer 25, which is further sandwiched between a liquid permeable topsheet 22 and a liquid barrier layer 23. The absorbent core 21 is disposed between the topsheet 22 and the liquid barrier layer 23, with the upper core cover layer 24 facing the liquid topsheet 22 and the lower core cover layer 25 facing the liquid barrier layer 23.

[0120] As disclosed herein, the provision of the absorbent core 21 is not limited to absorbent articles having the absorbent core applied to the article as a component of a prefabricated absorbent assembly that already includes a topsheet and liquid barrier layer.

[0121] The front portion 3 has a front waist edge 7 extending in the transverse direction T and a pair of front side edges 8, 9 extending in the longitudinal direction L. The rear portion 4 has a rear waist edge 10 extending in the transverse direction T and a pair of rear side edges 11, 12 extending in the longitudinal direction L.

[0122] The first front side edge 8 is joined to the first back side edge 11 at a first side seam 14, and the second front side edge 9 is joined to the second back side edge 12 at a second side seam 15 to produce a pant-type article 1 having a waist opening 16, a first leg opening 17 and a second leg opening 18, as shown in FIG. 6.

[0123] The side seams 14, 15 of the pant-type article 1 can generally be band-shaped joints, which are formed by ultrasonic or thermal welding. In order to have sufficient strength to withstand the forces to which the pant-type article 1 is subjected while the article is being worn, and to allow for sufficient production tolerances, the side seams generally have a width of the order of 5 to 10 millimeters. It is also known to make side seams with a width of less than 5 mm.

[0124] It is generally desired that soiled pant-type articles be easily removable without having to pull the article down the user's legs, and therefore the side seams are generally made so that they are breakable by manual force, allowing the user or caregiver to pull the side seams apart before removing the soiled pant-type article.

[0125] A waist opening 16 is defined by the front panel waist edge 7 and the back panel waist edge 10. A first leg edge 19' defines a first leg opening 17 and a second leg edge 19" defines a second leg opening 18.

[0126] 2, the absorbent material 70 has an hourglass shape with first and second side edges 26, 27 and first and second end edges 28, 29. The first and second side edges 26, 27 of the absorbent material 70 have a major extent in the longitudinal direction L and the first and second end edges 28, 29 have a major extent in the transverse direction T.

[0127] A first channel 35 and a second channel 36 are disposed in the absorbent material 70 and extend in the longitudinal direction L on either side of the longitudinal centerline Lc and at a predetermined distance from each of the first and second side edges 26, 27 of the absorbent material 70. The channels 35, 36 are free or substantially free of absorbent material.

[0128] Additionally, the upper and lower core cover layers 24 , 25 are connected by a first channel seal 37 that extends into the first channel 35 and by a second channel seal 38 that extends into the second channel 36 .

[0129] The upper and lower core cover layers 24, 25 can be formed from a single continuous piece of cover material that is wrapped around the absorbent core 21. In the pant-type absorbent article shown in the figures, the upper and lower core cover layers 24, 25 are formed from separate webs of material with absorbent material 70 sandwiched between the core cover layers 24 and 25.

[0130] Depending on the type and size of absorbent article in which one or more channels as disclosed herein are disposed, the length of the channel can range from 50 millimeters to 500 millimeters.

[0131] In a pant-type absorbent article for an incontinent adult user (such as the absorbent article 1 shown in the figures), the channels 35, 36 are preferably located in the crotch portion 6 of the article, which is the narrow portion of the article that will be placed at the crotch of the user when the article is worn. The narrow crotch portion 6 of the absorbent article is the portion of the article that will receive the majority of the discharged body fluids (such as urine). The crotch portion 6 must therefore have good absorption properties in terms of liquid acquisition, liquid distribution and absorption capacity. The channels 35, 36 in the absorbent material 70 contribute to rapid liquid acquisition and promote fluid distribution by directing the fluid flow towards the front and rear portions 3, 4 of the absorbent article 1. In the absorbent article 1 shown in the figures, the length of the channels 35, 36 corresponds substantially to the length of the crotch portion 6, which can typically be on the order of 100 to 250 millimeters.

[0132] In wearable incontinence articles (such as open diapers and pant-type diapers), the channels will typically have a length on the order of 30% to 50% of the total length of the absorbent core. In smaller absorbent articles (such as incontinence shields and sanitary napkins), the channels can extend almost to the ends of the absorbent core (such as up to 80% of the total length of the absorbent core).

[0133] In order to enhance the absorbent capacity in the narrow crotch area 6 of the absorbent article 1, the central part 51 of the absorbent core 21, which is arranged between the first end part 52 of the absorbent core 21 and the second end part 53 of the absorbent core 21, when viewed in the longitudinal direction L, has a greater thickness than the end parts 52, 53. In the absorbent article 1 shown in the figures, the first end part 52 is the front end part 52 of the absorbent core 21 and the second end part 53 is the rear end part 53 of the absorbent core 21.

[0134] The central part 51 of the absorbent core 21 has a uniform thickness, and each of the first and second end parts 52, 53 of the absorbent core 21 has a uniform thickness, and the central part 51 of the absorbent core 21 is separated from the first and second end parts 52, 53 by corresponding first and second transition zones 54, 55. The thickness of the absorbent core 21 decreases linearly in the transition zones 54, 55 from the central part 51 of the absorbent core 21 to the end parts 52, 53 of the absorbent core 21. The rear end part 53 has a greater extension in the longitudinal direction L of the absorbent article 1 than the front end part 52. In the absorbent core 21 shown in FIG. 2, the rear transition zone 55 has a greater extension in the longitudinal direction L of the absorbent article 1 than the front transition zone 54.

[0135] However, both transition zones may have equal extension in the longitudinal direction of the absorbent article, or the front transition zone may be longer than the rear transition zone. Absorbent cores with thickened central portions and thinner end portions, but without transition zones between different portions of the core, are also contemplated for absorbent articles as disclosed herein. Moreover, the central and end portions may have non-uniform thickness.

[0136] The ratio of the thickness of the central part 51 of the absorbent core 21 to the thickness of the front end part 52 can be in the range of 4 to 1.5, and the ratio of the thickness of the central part 51 of the absorbent core 21 to the thickness of the second end part 53 can be in the range of 4 to 1.5. The thinner end parts 52, 53 can have the same thickness or different thicknesses.

[0137] Moreover, it should be understood that the three-dimensional shape of the absorbent core is optional for absorbent articles as disclosed herein, and that the absorbent core may be planar or substantially planar. In planar or substantially planar absorbent cores, the absorbent capacity of the absorbent core may be different in different parts of the core as a result of different amounts of superabsorbent material being disposed in different parts of the core.

[0138] The absorbent core 21 as disclosed herein can include any absorbent material 70 suitable for absorbing excreted bodily waste products, such as cellulosic fluff pulp, tissue layers, highly absorbent polymers (superabsorbents), absorbent foam materials including hydrogel foam materials, or absorbent nonwoven materials. The absorbent core can include nonabsorbent components (e.g., reinforcing elements, shaping elements, binders, etc.). Various types of liquid receiving and distribution elements can also be included within the core.

[0139] The absorbent core 21 preferably comprises a superabsorbent material in an amount of 5% to 80% by weight (such as, for example, a superabsorbent material in an amount of 30% to 80% by weight) at least in the central part 51 of the absorbent core 21. As described herein, the superabsorbent content may be lower in the front end parts 52 and / or the rear end parts 53 of the absorbent core than in the central part 51 of the absorbent core 21, or may be the same in all parts of the absorbent core 21.

[0140] Superabsorbent materials are polymeric materials and can be in the form of particles, granules fibers, flakes, and the like.

[0141] As disclosed herein, the absorbent core 21 can include a mixture of absorbent cellulosic fibers (such as, for example, cellulose pulp fibers) and superabsorbent materials.

[0142] The high amount of superabsorbent material in the absorbent core allows for the production of thin, discrete absorbent articles while providing high absorbent capacity and the ability to chemically bind and immobilize absorbed fluids, resulting in absorbent articles that have high leak-proofing and dry inner surfaces even after absorbing large amounts of fluid.

[0143] As shown diagrammatically in FIG. 2, the absorbent core 21 can be divided along the channel seal length Ls into a virtual set of one or more adjacent transverse segments S1-S9. Each transverse segment has a segment length of 10 mm and includes a portion of the channel seal. The set of one or more transverse segments includes the maximum number of adjacent segments possible along the channel seal length. As such, the number of segments in a set can be found by dividing the channel seal length Ls by 10 mm and rounding down to the nearest integer.

[0144] In FIG. 2, an imaginary set of adjacent transverse segments S1-S9 is illustrated by dashed and dotted lines.

[0145] Figure 3a shows a transverse cross-section taken along line III-III through absorbent core 21 of Figure 2. The depicted transverse cross-section is taken along a transverse centerline through one transverse segment S3 of an imaginary set of adjacent transverse segments S1 to S9.

[0146] FIG. 3a shows the absorbent core 21 in a dry state, before it has absorbed any liquid.

[0147] The absorbent core has a length in a longitudinal direction L, a width in a transverse direction W, and a height in a thickness direction H, the thickness direction H being perpendicular to the longitudinal and transverse directions. The absorbent core 21 includes an upper core cover layer 24 and a lower core cover layer 25, and an absorbent material 70 sandwiched between the upper and lower core cover layers 25. The absorbent core 21 includes a pair of channels 35, 36 extending longitudinally in the absorbent material 70, each of the channels 35, 36 being free or substantially free of absorbent material. Each of the channels 35, 36 has a channel seal 37, 38 extending therethrough that joins the upper and lower core cover layers 24, 25 within the channels 35, 36. As seen in transverse cross section in Figure 3, the upper and lower core cover layers 24, 25 form a space between the channel seals 37, 38, which space contains an absorbent material 70. In use, the absorbent material 70 will absorb liquid and swell. For example, when the absorbent material 70 includes a superabsorbent material, the superabsorbent material will absorb liquid upon swelling and forming an aqueous gel.

[0148] In order to fully utilize the absorbent capacity of the absorbent material 70, the absorbent article must provide sufficient expansion space for the superabsorbent material 70. As can be seen between channel seal 35 and channel seal 36, the space for lateral swelling is limited.

[0149] As illustrated in FIG. 3a, in order to provide additional space for swelling of the absorbent material 70 between the channel seals 37 and 38, the absorbent core 21 has a first width W1 when the upper core cover layer 24 is viewed along itself, i.e., in an unfolded, completely flat state, and a second width W2 when the lower core cover layer 25 is viewed along itself, i.e., in an unfolded, completely flat state, where the first width W1 is greater than the second width W2. For example, the first width can be 120% or more (e.g., 130% or more) of the second width W2. Thus, additional space for the absorbent material 70 between the channel seals 37 and 38 is provided, allowing increased swelling of the absorbent material 70 between the channels 35 and 36 in the thickness direction. The first and second widths W1, W2 between channel seal 37 and channel seal 38 in the deployed, fully flat state can be determined according to the method described in the Methods section below of this application.

[0150] For example, the first width W1 can differ from the second width W2 by 3 mm or more (eg, 5 mm or more, or 7 mm or more).

[0151] As illustrated in FIG. 3a, the third width can be measured between channel seal 37 and channel seal 38, and this third width can be in the range of 20 mm to 60 mm, such as in the range of 25 mm to 45 mm.

[0152] Alternatively, or in addition to providing additional space for swelling of the absorbent material 70 between the channel seals 37 and 38, the absorbent core 21 can be adapted to provide additional space for swelling of the absorbent material 70 in portions laterally outboard of the channel seals 37, 38.

[0153] As shown in FIG. 3a, the upper core cover layer 24 and the lower core cover layer 25 can be in contact with each other in a first side region 33 extending along a first side edge 26 of the absorbent material, and in a second side region 34 extending along a second side edge 27 of the absorbent material 70.

[0154] As such, the first side region 33 is the region of the absorbent core 21 that extends transversely beyond the first side edge 26 of the absorbent material 70 to a first side edge 71 of the absorbent core 21. Similarly, the second side region 34 is the region of the absorbent core 21 that extends transversely beyond the second side edge 27 of the absorbent material 70 to a second side edge 72 of the absorbent core 21. As can be seen in Figure 3a, the first and second side edges 71, 72 of the absorbent core 21 are considered to be edges that delimit the mutual extension of the upper core cover layer 24 and the lower core cover layer 25.

[0155] In some variations (not shown), the upper core cover layer and the lower core cover layer can be connected at a first side seal extending into the first side region 33 and at a second side seal extending into the second side region 34.

[0156] In order to provide additional space for swelling of the absorbent material 70 in the laterally outer portions of the channel seals 37, 38 (i.e. laterally adjacent to the first and second side regions 33, 34, respectively), the side seals can be adapted to be breakable seals, i.e. intended to break under the effect of a force exerted on them when the absorbent material in the absorbent core absorbs fluid and expands. As such, the channel seals can have a higher seal strength than the respective seal strengths of the first and second side seals. To this end, for example, the seal strength of the channel seal can be 2.5 N / 25 mm or more, and the seal strength of the first and second side seals can be 2.0 N / 25 mm or less.

[0157] In other variations (such as, for example, that illustrated in Figure 2), the upper core cover layer 24 and the lower core cover layer 23 may not be sealed to one another. Thus, the first side region 33 extending along the first side edge 26 of the absorbent material and the second side region 34 extending along the second side edge 27 of the absorbent material may be free of seals.

[0158] The absence of seals in the first and second side regions 33, 34 of the absorbent core 21 means that there are no seals present that provide significant seal strength. However, the first core cover layer 24 and the second core cover layer 25 may still have some slight connection (albeit with very low connection integrity) due to, for example, a frictional connection between the cover layers 24 and 25.

[0159] As in the example of Figure 3a, when no side seal is present between the first core cover layer 24 and the second core cover layer 25, the absorbent material 70 in the transversely outer portions of the channels 35, 36 is therefore able to swell transversely beyond the extension of the core width Wc, i.e. beyond the mutual extension of the core cover layers 24, 25.

[0160] As illustrated in Figure 3a, the absorbent material 70 can have an absorbent width Wa as viewed in a transverse cross-section of the core, in which the upper and lower core cover layers 24, 25 extend across one another, which is the core width Wc.

[0161] The absorbent width Wa is smaller than the core width Wc. Due to the increased space for swelling of the absorbent material 70 that may be provided as described above for the absorbent material between the channel seals and / or for the absorbent material in the transversely outer portions of the channel seals, the core width Wc may be relatively narrow. As such, the absorbent width Wa may be 90% or more of the core width Wc (e.g., 95% or more of the core width Wc).

[0162] Figure 3b illustrates another example of an absorbent core 21. The absorbent core 21 of Figure 3b is similar to the absorbent core of Figure 3a, except that the upper core cover layer 24 is arranged to be folded around the transverse side edges of the lower core cover layer 25. Also, the core width Wc, which is the mutual transverse extension of the upper core cover layer 24 and the lower core cover layer 25, is in this case equal to the width of the lower core cover layer 25.

[0163] Figures 4a and 4b show a cross section taken along line III-III through the absorbent assembly of Figure 2 with an absorbent core 21 as illustrated in Figure 3a. Figure 4a shows the absorbent core 21 in a dry state, before it has absorbed liquid, and Figure 4b shows the absorbent core 21 in a wet state, after it has absorbed and swelled.

[0164] An absorbent core 21 with an upper core cover layer 24 and a lower core cover layer 25 is shown disposed between a liquid permeable topsheet 22 and a liquid barrier layer 23. The absorbent core 21 is disposed between the topsheet 22 and the liquid barrier layer 23 with the upper core cover layer 24 facing the liquid topsheet 22 and the lower core cover layer 25 facing the liquid barrier layer 23.

[0165] The topsheet 22 and the liquid barrier layer 23 extend beyond the periphery of the absorbent core 21 and are joined to one another at an edge seal 41 that extends along the periphery of the absorbent core outwardly of the side edges 26, 27 and end edges 28, 29 of the absorbent core 21. The edge seal 41 between the topsheet 22 and the liquid barrier layer 23 is preferably a permanent seal.

[0166] The upper core cover layer 24 and the lower core cover layer 25 extend across the absorbent core 21 across their mutual width, which is the core width Wc as defined herein. In the example of Figures 3, 4a, the upper core cover layer 24 and the lower core cover layer 25 have the same width, and thus the core width Wc.

[0167] The edge seal 41 extends along and directly adjacent the first and second side edges 26, 27, respectively, of the absorbent material. By "directly adjacent" it is meant that there are no other seals between the first or second edge seal 41 and the first or second side edges, respectively, of the absorbent material 70. The edge seal 41 is thus the seal that limits the possible expansion of the absorbent material 70 in the transverse direction. The width between the first edge seal 41 and the second edge seal 41 is defined as the sealed width Ws.

[0168] In the transverse cross section shown, the sealed width Ws is greater than the core width Wc. The first and second edge seals 41 therefore extend outwardly in the transverse direction of the mutual extension of the upper and lower core cover layers 24, 25. This means that the absorbent material 70 in the laterally outer parts of the channels 35, 36 can swell transversely beyond the core width Wc. Thus, additional space for swelling is provided. It will be understood that this way of realizing additional space for swelling in the transverse direction of the absorbent article can be advantageously combined with the above-mentioned way of realizing additional space for swelling in the height direction of the absorbent article. Moreover, the two proposed ways of realizing additional space for swelling can also be used separately.

[0169] Fig. 4a illustrates a variation of the absorbent assembly when it is in a dry, unused state, as described above. Fig. 4b illustrates the absorbent assembly of Fig. 4a when the absorbent core absorbs a relatively large amount of bodily fluid. When the absorbent core 21 absorbs bodily fluid, the absorbent material 70 in the absorbent core 21 swells, causing the portion of the absorbent material 70 located between the channels 35 and 36 and trapped between the channel seals 37 and 38 to fill the available space between the channels 35 and 36 and to expand in thickness. Thus, the additional space created by the first width W1 being greater than the second width W2 is utilized. The portions of the absorbent material 70 positioned laterally outward of the channels 35, 36 with the permanent channel seals 37, 38 are allowed to expand primarily in the transverse direction into and beyond the side regions 33, 34 until the side edges 26, 27 of the swelling absorbent material 70 reach the edge seals 41. Thus, the lateral swelling of the absorbent material 70 can cause the side edges 26, 27 of the absorbent material 70 to move outward in the transverse direction T, which can cause the hourglass shape of the absorbent material 70 (as initially present) to gradually disappear.

[0170] Other variations in the absorbent assembly are possible. For example, the absorbent assembly may include an absorbent core as illustrated in Figure 3b.

[0171] In general, the absorbent article may include one or more additional upper layers and / or one or more additional lower layers. One of the additional upper layers may include a liquid permeable topsheet 22. One of the additional lower layers may include a liquid barrier 23. First and second edge seals 41 may be bonded between one of the additional upper layers 22 and one of the additional lower layers 23. For example, first and second edge seals 41 may be bonded between one of the additional upper layers 22 and the lower core cover layer 25. For example, first and second edge seals 41 may be bonded between one of the additional lower layers 23 and the upper core cover layer 24.

[0172] As illustrated in Figures 4a-b, the absorbent article can include a topsheet 22 adjacent to an upper core cover layer 24, and a barrier layer 23 adjacent to a lower core cover layer 25. As in the example of Figures 4a-b, an edge seal 41 can join the topsheet 22 and the barrier layer 23.

[0173] Figure 5 illustrates another example of an absorbent article. Figure 5 is similar to Figure 4a, except that the lower core cover layer 25 has a greater width than the upper core cover layer 24 (as seen in the article's dry state). Thus, the core width Wc (which is the mutual width of the upper core cover layer 24 and the lower core cover layer 25) is equal to the width of the upper core cover layer 24 in this case. An edge seal 41 is positioned to join the lower core cover layer 25 and the topsheet 22. As seen in Figure 4, the sealed width Ws between the edge seals 41 is greater than the core width Wc.

[0174] The liquid pervious topsheet 22 can include or be composed of a nonwoven material. Other suitable topsheet materials include tow fibers, porous foams, apertured plastic films and laminates, and combinations of such materials. Materials optimal for the topsheet material are soft and nonirritating to the skin, are easily penetrated by bodily fluids, and exhibit low rewet.

[0175] The liquid barrier layer 23 can be composed of a thin plastic film (e.g., polyethylene or polypropylene film), a nonwoven material coated with a liquid impermeable material, a hydrophobic nonwoven material that resists liquid penetration, or a laminate of a plastic film and a nonwoven. The liquid barrier layer material can be breathable to allow vapor to escape from the absorbent body portion while still preventing liquid from passing through the liquid barrier layer material.

[0176] The topsheet and / or liquid barrier layer can be further attached to the core-cover layer by any method known in the art (eg, adhesive, thermal bonding, welding, etc.).

[0177] The edge seal 41 can be formed, for example, by adhesive bonding, gluing, or heat or ultrasonic welding.

[0178] A pant-type article as disclosed herein may have a two-part chassis with a crotch panel connected to the front panel along the front panel crotch edge and connected to the rear panel along the rear panel crotch edge. The front and rear panels may be made of elastic or stretchable web materials or elastic laminate materials, and the crotch panel may be an inelastic web material or an inelastic laminate material. Alternatively, the pant-type article may have a unitary chassis with an inelastic outer or inner cover web extending the entire distance between the front panel waist edge and the rear panel waist edge, the cover web constituting the inelastic layer of each of the front and rear panels and constituting the crotch web material in the crotch region of the pant-type article.

[0179] The elastically stretchable front body panel and the elastically stretchable rear body panel can include or be constructed from a stretch bonded laminated elastic web material.

[0180] Suitable stretch-bonded laminates can include nonwoven material layers or webs (e.g., spunbond, airlaid, wetlaid, carded, electrospun, or meltblown nonwovens, etc.) The nonwoven materials can be bonded by any suitable technique (e.g., by needling, hydroentangling, ultrasonic welding, or thermobonding, etc.).

[0181] The fibers of the nonwoven material used herein can be man-made, natural, or a mixture of man-made and natural fibers. Man-made fibers include polymeric monocomponent, bicomponent, and multicomponent fibers (e.g., polyolefins, polyesters, polyacrylates, etc.), and regenerated fibers (e.g., viscose and modal fibers, etc.). Natural fibers are, for example, cellulosic fibers (e.g., pulp fibers, cotton fibers, flax, hemp, etc.).

[0182] The pant-type article 1 as disclosed herein can have an elastic waist feature 90 disposed along the waist opening 16. The elastic waist feature 90 can be formed by one or more elastic elements extending parallel to the front panel waist edge 7 and the back panel waist edge 10. The one or more elastic waist elements can be incorporated into the front portion 3 and the back portion 4, or can be applied as a separate waistband attached to the front panel waist edge 7 and the back panel waist edge 10. The pant-type article 1 shown in the figures has an elastic waist feature 90 extending around the entire perimeter of the waist opening 16. However, the elastic waist feature can be disposed only along a portion of the waist opening (e.g., only along the back waist edge, only along the front waist edge, or along a portion of one or both of the front and back waist edges (wherein the portion has a length less than the full length of the corresponding waist edge)).

[0183] The elastic material in the elastic elements disposed along the leg openings 17, 18 and waist opening 16 as disclosed herein can be any suitable elastic material such as, for example, natural or synthetic rubber, thermoplastic elastomers (e.g., thermoplastic polyurethanes or styrene block copolymers or elastane (also called spandex (polyurethane-polyurea copolymer))), etc. The elastic elements can be of the elastane type available under the trade name "LYCRA", although any suitable elastic yarn can be used.

[0184] The nonwoven web material used in absorbent articles as disclosed herein can include thermoplastic materials. Nonwoven web materials will typically be incorporated into the joints and seams in absorbent articles, and it may be desirable for the nonwoven web to be weldable by heat or ultrasonic welding process. Examples of suitable polymers for use in fibrous nonwoven webs as disclosed herein are polyethylene, polypropylene, and other polyolefin homopolymers and copolymers, and polyester. Weldable nonwoven webs have a high content of thermoplastic components, preferably containing at least 50% thermoplastic fibers, more preferably at least 80% thermoplastic fibers.

[0185] Manufacturing method Any suitable manufacturing method can be used to produce an absorbent core as described herein. For example, the absorbent material can be produced by a method for manufacturing an absorbent core for a disposable absorbent hygienic article as disclosed herein, which method comprises: - providing a first core cover web having a first surface and a second surface, and advancing the first core cover web in a machine direction, the first core cover web having side edges extending in the machine direction, a first core cover width being defined in a cross machine direction between the side edges of the first core cover web, the cross machine direction being perpendicular to the machine direction; - reducing a width of the first core cover web by introducing at least one pleat into the first core cover web, the at least one pleat extending in the machine direction between side edges of the first core cover web to form a pleated first core cover web, the pleated first core cover web having a second core cover width between the side edges of the pleated first core cover web, the second core cover width being smaller than the first core cover width; - applying an adhesive to a first surface of the pleated first core cover web; - advancing the pleated first core cover web onto a mat-forming surface of a mat-former having a recess disposed on the mat-forming surface, the recess having an air permeable bottom surface and including at least one channel-forming element disposed above and protruding from the bottom surface of the recess; - fitting the pleated first core cover web into the recess and at least one channel-forming element on a bottom surface of the recess, a second surface of the first core cover web facing the bottom surface of the recess, causing the pleats in the first core cover web to at least partially unfold in the at least one channel-forming element; - applying an absorbent material onto a first surface of the first core cover web within the recess; - providing a second core cover web having a first surface and a second surface; - applying an adhesive onto a first surface of a second core cover web; - applying a second core cover web to the first core cover web and to an absorbent material disposed on the first core cover web; - forming an absorbent laminate including an absorbent material, the second core cover web, and the first core cover web by pressing the second core cover web together; - cutting the absorbent laminate in the cross machine direction to form individual absorbent cores; Includes.

[0186] Referring initially to FIG. 11, there is shown a schematic diagram of a method for producing an absorbent core for use in disposable absorbent sanitary articles.

[0187] The method shown in Figure 11 is carried out using a mat-former 101 including a rotatable mat-forming drum 102. A first core cover web 104 having a first surface 105 and a second surface 106 is advanced in a machine direction MD.

[0188] The first core cover web 104 is passed through a pleat forming unit 108 where two pleats 109 are formed in the first core cover web 104 as seen in FIG. 14 , the pleats 109 extending in the MD between the side edges of the first core cover web 104. Although two pleats are shown and described herein, it should be understood that any suitable number of pleats (e.g., one pleat, three pleats, or more pleats, etc.) can be formed in the first core cover web 104 by the pleat forming unit 108. By pleating the first core cover web 104, the width w of the first core cover web 104 is reduced such that the second width w2 of the pleated first core cover web 104′ is less than the first width w1 of the unpleated first core cover web 104. The widths w1, w2 of the unpleated and pleated first core cover webs 104, 104' are measured between the side edges 111 of the first core cover web 104 in the cross machine direction CD perpendicular to the MD, as shown in FIG. 14.

[0189] In a next step, an adhesive (such as, for example, a liquid adhesive) is applied to the first surface 105 of the pleated first core cover web 104' by a first adhesive applicator 110. After application of the adhesive, the pleated first core cover web 104' is advanced onto a mat-forming surface 112 on a rotatable mat-forming drum 102 of a mat former 101. The mat-forming drum 102 has a recess 113 disposed on the mat-forming surface 112 (see Figures 14 and 15), the recess 113 having a bottom surface 114 and including two channel-forming elements 115. The channel-forming elements 115 are disposed on and protrude from the bottom surface 114 of the recess 113. With respect to the pleats 109 in the first core cover web 104, the number of channel-forming elements on the bottom surface 114 of the recess 113 can be varied as disclosed herein. Thus, a single channel forming element may be used, or three or more channel forming elements may be used. The number of channel forming elements 115 can correspond to the number of pleats 109 in the first core cover web 104, and the location of the pleats 109 in the first core cover web 104 can be synchronized with the placement of the channel forming elements 115.

[0190] The pleated first core cover web 104' is then sucked into the recess 113 by a vacuum force V, which is applied through the air permeable bottom surface 114 of the recess 113 from the inside of the rotating mat-forming drum 102.

[0191] As illustrated by Figure 15, the pleated first core cover web 104' as seen in the upper part of the figure is moved in the direction of arrow A into the recess 113 and adapted to the shape of the recess 113 and to the two channel forming elements 115 therein, with the second surface 106 of the first core cover web facing the bottom surface 114 of the recess 113. During this process, the pleats 109 in the core cover web 104 are caused to unfold and cover the bottom of the recess 114 and the channel forming elements 115, as seen in the lower portion of Figure 15. The pleated core cover web 104' is drawn into the recesses 113 by a vacuum force V applied from inside the rotating mat-forming drum 102, causing the pleats 109 in the pleated first core cover web 104' to unfold in the channel-forming element 115 and to easily conform to the shape of the channel-forming element 115 due to the excess material that becomes available as the pleats 109 unfold. The pleats in the first core cover web 104 allow the first core cover web 104 to conform to the shape of the protruding channel-forming element 115 without undue stretching or tensioning of the first core cover web 104.

[0192] This is different from the prior art application of the first core cover web 104 to the recess 113 having the channel forming element 115, as shown in Figures 12 and 13. In the prior art application of the first core cover web 104, the first core cover web 104 is sucked into the recess 113 by the vacuum force V, causing stresses to build up in the material at the relatively sharp edges and corners of the channel forming element 115. Tensions in the first core cover web material can cause the first core cover web to tear or puncture. In addition, the prior art first core cover web 104 has a lower ability to conform to the shape of the recess 113, which means that the space available for filling the recess with absorbent material is reduced by the non-conforming parts of the first core cover web 104, as shown in Figure 13.

[0193] An absorbent material is then applied onto the first surface 105 of the first core cover web in the recesses 113 on the mat-forming surface 112 of the rotating mat-forming drum 102. In Figure 11, the application of the absorbent material is illustrated by an air-laying unit 120 in which air-entrained wood pulp 121 is mixed with superabsorbent material 122 (e.g., superabsorbent particles or fibers) and the mixture is drawn into the recesses 113 that are covered by the first core cover web 104.

[0194] After application of the absorbent material, a second core cover web 124 having a first surface 125 and a second surface 126 is provided and an adhesive (such as, for example, a liquid adhesive) is applied to the first surface 125 of the second core cover web 124 by a second adhesive applicator 130. The second core cover web 124 is advanced onto the rotating wheel 131 with the second surface 126 of the second core cover web 124 facing the rotating wheel 131. The second core cover web 124 is applied by the rotating wheel 131 to the mat forming surface 112 of the rotatable mat forming drum 102 so as to cover the first core cover web 104 in the recess 113 and the absorbent material 121, 122 disposed on the first core cover web 104.

[0195] The first surface 125 of the second core cover web 124 is attached to the first surface 105 of the first core cover web 104 and to the absorbent materials 121, 122 disposed on top of the first core cover web 104 in the recess 113 in the mat forming surface 112 of the mat forming drum 102 by pressing the second core cover web 124 and the first core cover web 104 together in the nip 135 between the two rollers to form an absorbent laminate 140 including the absorbent materials 121, 122, the second core cover web 124, and the first core cover web 104. Pressing the second core cover web 124 and the first core cover web 104 together places the core cover webs in direct or substantially direct contact with each other in areas generated in the channel forming elements 115 that are generally free of absorbent material, and in corresponding areas of the second core cover web 124 and the first core cover web 104 that are positioned outside the recesses 113.

[0196] Alternatively, or in addition, forming the absorbent laminate 140 can include pressing the second core cover web and the first core cover web together in a nip 134 between the rotating wheel 131 and the rotating mat-forming drum 102.

[0197] After forming the absorbent laminate 140 , individual absorbent cores 142 are formed by cutting the absorbent laminate 140 in the cross machine direction at a cutting unit 141 .

[0198] Although the method as disclosed herein has been illustrated using a mat-forming machine 101 having a rotating mat-forming drum 102, it should be understood that the method as disclosed herein is equally applicable to mat formation on a moving conveyor.

[0199] The recess 113 in the mat-forming surface 112 of the mat-forming drum 102 can be a continuous recess extending around the entire circumference of the mat-forming drum 102, or the recess can be one of a number of recesses distributed equidistantly around the circumference of the mat-forming drum 102.

[0200] As disclosed herein, each channel-forming element 115 in the successive recesses can be composed of multiple element parts, which are distributed equidistantly around the circumference of the mat-forming drum 102. When two channel-forming elements are arranged side-by-side, the element parts are arranged in pairs around the circumference of the mat-forming drum 102. When cutting the absorbent laminate 140 to form the individual absorbent cores 142, the absorbent laminate 140 is cut in the cross machine direction CD between the element parts. Thus, the number of channel-forming element parts of each channel-forming element 115 corresponds to the number of cores formed on the mat-forming drum during one revolution.

[0201] The adhesive can be evenly distributed on the first surface 105 of the pleated first core cover web 104'. Similarly, the adhesive can be evenly distributed on the first surface of the second core cover web 124.

[0202] Alternatively, adhesive can be selectively dispensed onto one or both of the core cover webs 104, 124 to produce any desired bond pattern.

[0203] Further details regarding the manufacturing methods as described above can be found in co-pending US Pat. No. 5,399,633.

[0204] The present disclosure may be modified within the scope of the appended claims, for example in materials and dimensions.

[0205] Test Method For all measurements, the article or absorbent core is in a dry, unused condition as provided prior to use.

[0206] Test Methods for Measuring Seal Strength At least 10 days must elapse between the manufacture of the article and the opportunity for seal strength measurement.

[0207] The core with the surrounding cover layer is carefully separated from the other components of the absorbent article. If the lower core cover layer cannot be separated from the backsheet of the absorbent article without damaging the lower core cover layer, the backsheet should remain attached to the lower core cover layer when performing the seal strength test.

[0208] The exposed core with the core cover layer is laid flat on a support surface. If elastic material is present in the core, the core should be stretched and secured in place on the support surface using strips of tape, mechanical fasteners, or the like.

[0209] Rectangular samples (25 mm wide) are punched out of the core, each containing a portion of the seal to be tested. The samples are punched out with the width of each sample parallel to the longitudinal centerline of the core and the length of each sample perpendicular to the longitudinal centerline of the core. The samples are punched out so that the seal extends across the outer edge of the sample, and the inner end portions of the upper and lower core cover layers form cover flaps that extend toward the longitudinal centerline of the article. Any loose absorbent material between the core cover flaps is removed. The core cover flaps can be stretched and / or reinforced with high friction tape to ensure a stable, slip-free attachment in the tensile tester clamps. It is important that the longitudinal edges of the specimen are uniform and free of fracture notches.

[0210] The samples are punched immediately adjacent to each other, for example, from a seal having a length of 210 mm, eight 25 mm wide test samples can be punched, with 10 mm remaining at one end of the seal and not used for testing.

[0211] The samples (prepared as described above) are conditioned for 24 hours in a controlled environment with the temperature set at 23° C.+ / -1° C. and 50%+ / -5% relative humidity. Testing is carried out in this same environment.

[0212] The samples are tested in a conventional tensile testing machine (eg, such as those available from Lloyd Instruments or Instron Corporation).

[0213] The core cover flap is inserted vertically into the clamps of the tensile tester. The clamps should be at least as wide as the sample. Upon insertion, tension on the seal should be avoided, but also excessive slack in the sample being tested. The upper crosshead of the instrument is then set to move at a constant speed of 300 mm / min along the seal being tested until the upper core cover layer separates from the lower core cover layer. The maximum force measured is registered in Newtons / 25 mm (N / 25 mm). Figures 7 and 8 illustrate how the specimen is mounted into the clamps of the test instrument.

[0214] The seal strength of a tested seal is the arithmetic mean value based on all the individual samples that can be cut along the part of the seal to be examined. For example, the overall strength of a 210 mm long seal as described above is the average of the seal strengths obtained from testing eight specimens punched along the seal.

[0215] Thickness measurement The thickness is measured under a pressure of 0.5 kPa.

[0216] A suitable thickness gauge has a square foot measuring 5x5cm (however, a smaller foot can be used for smaller areas of interest). The foot should be lowered gently onto the material and the thickness value read after 5 seconds.

[0217] Width and length measurements It should be noted that by the terms "length" and "width" as used in this application, unless otherwise stated, it is meant the maximum longitudinal dimension for length and the maximum transverse dimension for width as seen on the absorbent core or article when in a dry, unused state. Prior to dimensional measurements, any elastic components are neutralized (e.g., by cutting them at regular intervals, etc.) and the object is placed flat against a planar surface. Measurements on the core are taken after removal from any surrounding elastic chassis.

[0218] Test method for measuring the width of the core-cover layer in the folded state A method for measuring the width of the core cover layers 24, 25 in the deployed state and between the channel seals 37 and 38 in a transverse segment of the absorbent core will now be described with reference to Figures 9 and 10.

[0219] The core with surrounding core cover layers 24, 25 is carefully separated from the other components of the absorbent article. If the lower core cover layer 25 cannot be separated from the backsheet of the absorbent article without damaging the lower core cover layer, the backsheet should remain attached to the lower core cover layer when taking the width measurements.

[0220] The exposed core with the core cover layer is laid flat on a support surface. If elastic material is present in the core, the core should be stretched and secured in place on the support surface using strips of tape, mechanical fasteners, or the like.

[0221] Rectangular samples (10 mm wide) were punched out from the core immediately adjacent to each other, such that each sample corresponds to a transverse segment in an imaginary set of adjacent transverse segments S1 to S9 of the absorbent core 21, as described above in relation to FIG. 2.

[0222] Samples are die cut with the width of each sample parallel to the longitudinal centerline of the core and the length of each sample perpendicular to the longitudinal centerline of the core.

[0223] As noted above, samples are punched immediately adjacent to one another. For example, twenty-one 10 mm wide test samples can be punched from an absorbent core with a pair of channels having a channel seal with a longitudinal channel seal length of 215 mm, with 5 mm of channel seal remaining at one end and not used for testing.

[0224] The samples (prepared as described above) are conditioned for 24 hours in a controlled environment with the temperature set at 23° C.+ / -1° C. and 50%+ / -5% relative humidity. Testing is carried out in this same environment.

[0225] In each sample, a closed "tube" is formed by the portion of upper core cover 24c extending between channel seal 37 and channel seal 38 and the portion of lower core cover 25c extending between channel seal 37 and channel seal 38. The tube is filled with absorbent material 70.

[0226] The "tube" is slit open by cutting the upper core cover 24 between channel seals 37 and 38 along a line substantially parallel to the width of the sample (i.e., substantially parallel to the longitudinal axis L of the core). Absorbent material 70 is gently removed from the slit open tube. Material transverse to seal 37 can also be removed for purposes of determining the width of the core cover layers 24, 25 between channel seals 37 and 38 in the deployed state.

[0227] The tube is slowly unfolded so that the unfolded tube, as viewed in the length direction of the sample (transverse direction T of the core), includes a first cut edge 81, followed by a first portion 24c' of the upper core cover 24, a first channel seal 37, a portion 25c of the lower core cover 25, a second channel seal 38, a second portion 24c" of the upper core cover 24, and is terminated by a second cut edge 82.

[0228] The channel seals 37, 38 are identified and their extension along the length of the sample is marked.

[0229] The tubing is unfolded and suspended perpendicular to the longitudinal dimension of the sample and measurements are performed.

[0230] The first cut edge 81 extends along the horizontal direction. For example, the first cut edge 81 can be suspended in the horizontal direction by a clamp.

[0231] A 10 g weight is attached to the second cut edge 82 of the tubing, stretching the sample material along the length of the sample such that the force from the weight is evenly distributed across the width of the sample, so that the sample material is suspended with the long dimension of the sample parallel to the vertical.

[0232] The width W2 of the lower core cover material 25c between the channel seals 37 and 38 is measured vertically between the markings identifying the channel seals 37, 38 and along the length of the sample. The measurement is taken along the centerline of the sample.

[0233] The width W1 of the upper core cover material between the channel seal 37 and the channel seal 38 is the sum of the vertical length W1' between the first cut edge 81 and the first channel seal 37 and the vertical length W1" between the second channel seal 38 and the second cut edge 82. Measurements are taken vertically and along the length of the sample. Measurements are taken along the centerline of the sample.

[0234] Thus, measurements of widths W1, W2 between channel seal 37 and channel seal 38 in the sample are taken at the same transverse cross section for the first and second core cover layers.

[0235] From measurements of the first and second widths W1, W2 on each sample (corresponding to one imaginary segment of the absorbent core), the relationship between the first and second widths on the corresponding transverse segment can be calculated, and thus measurements taken along the centerline of the sample are considered to be representative of the corresponding transverse segment.

[0236] In some variations, each one of the first and second widths W1, W2 can have the same value in each imaginary segment along the channel seal length Ls, for example, in some variations where the channel containing the channel seals 37, 38 is straight and extends parallel to the longitudinal direction.

[0237] In other variations, each one of the first and second widths W1, W2 can have different values ​​at different imaginary segments along the channel seal length, as may be the case, for example, in some variations where the channel containing the channel seal 37 is straight but angled with respect to the longitudinal direction L, or in some variations where the channel with the channel seal is curved.

[0238] Further, a relationship between the first width W1 and the second width W2 can be determined for each sample. [Explanation of symbols]

[0239] 1 Pants-type items 3 Front part 4 Rear part 6 Crotch area 7 Front waist edge 8 First front side edge 9 Second front side edge 10 Rear panel waist edge 11 first rear side edge 12 second rear side edge 14 First side seam 15 Second side seam 16 Waist opening 17 First leg opening 18 Second leg opening 19' First leg edge 19” Second leg edge 20 Absorbable Assembly 21 Absorbent Core 22 Top sheet 23 Liquid Barrier Layer, Additional Lower Layer 24 Upper core cover layer 24c Upper core cover 24c' First portion of upper core cover 24 24c" second part of upper core cover 24 25 Lower core cover layer 25c Lower core cover 26 first side edge 27 Second side edge 28 first end edge 29 Second end edge 33 First Side Region 34 Second Side Region 35 First Channel 36 Second Channel 37 First Channel Seal 38 Second Channel Seal 41 First edge seal 51 Central part 52 front end part, first end part 53 Rear end part, second end part 54 Anterior transition zone, first transition zone 55 Posterior Transition Zone, Second Transition Zone 70 Absorbent Materials 71 first side edge 72 second side edge 81 First cut edge 82 Second cut edge 90 Elastic waist feature 101 Mat forming machine 102 Rotating mat forming drum 104 First core cover web 104' 1st core cover web 105 First Surface 106 Second Surface 108 Pleats forming unit 109 Pleats 110 First adhesive applicator 111 Side edge 112 Matte Forming Surface 113 Recess 114 Bottom surface 115 Channel-forming elements 120 Air Laying Unit 121 Wood pulp 122 Superabsorbent Materials 124 Second core cover web 125 First Surface 126 Second Surface 130 Secondary adhesive applicator 131 Spinning Wheel 140 Absorbent Laminate 141 Cutting Unit 142 Absorbent core CD Cross Machine Direction H Thickness direction L Longitudinal Lc Longitudinal center line MD Machine Direction S1~S9 Adjacent transverse segments T transverse direction V vacuum force W1 First width W1': the vertical length between the first cut edge 81 and the first channel seal 37 W1″: the vertical length between the second channel seal 38 and the second cut edge 82 W2 Second width W3 Third width Wa absorber width Wc Core width Ws Sealed width

Claims

1. an absorbent core (21) having a length in a longitudinal direction (L) and a width in a transverse direction (T), said transverse direction (T) being perpendicular to said longitudinal direction (L); The absorbent core (21) includes an upper core cover layer (24) and a lower core cover layer (25), and an absorbent material (70) sandwiched between the upper core cover layer (24) and the lower core cover layer (25); The absorbent core (21) includes a pair of channels (35, 36) extending in the longitudinal direction in the absorbent material (70); each of said channels (35, 36) being free or substantially free of absorbent material and having a channel seal (37, 38) extending therethrough; the channel seals (37, 38) join the upper and lower core cover layers (24, 25) within the channels (35, 36) and extend along a longitudinal channel seal length (Ls); the absorbent core being divided along the channel seal length (Ls) into an imaginary set of one or more adjacent transverse segments (S1-S9); Each transverse segment has a segment length of 10 mm and includes said channel seal (37, 38); the set includes the maximum possible number of adjacent transverse segments (S1-S9) along the channel seal length (Ls); The absorbent core (21) has, for at least one transverse segment of the set of segments: One of the lower core cover layer (25) and the upper core cover layer (24) has a first width (W1) between the channel seal (37) and the channel seal (38), and the other of the lower core cover layer (25) and the upper core cover layer (24) has a second width (W2) between the channel seal (37) and the channel seal (38), the first and second widths (W1, W2) of the core cover layers (24, 25) being the width of the core cover layers (24, 25) between the channel seal (37) and the channel seal (38) in a fully deployed, flat state, and the first width (W1) is equal to or greater than 120% of the second width (W2). The absorbent core (21) is configured as follows.

2. 2. The absorbent core of claim 1, wherein in at least one said transverse segment, said first width (W1) is greater than or equal to 130% of said second width (W2), for example greater than or equal to 135% of said second width (W2).

3. 3. The absorbent core according to claim 1 or 2, wherein in at least one said transverse segment, said first width (W1) differs from said second width (W2) by 3 mm or more, for example by 5 mm or more or 7 mm or more.

4. 4. The absorbent core according to claim 1, wherein in at least a portion of the absorbent core (21), the upper core cover layer (24) and the lower core cover layer (25) are connected at a first side seal in a first side region (33) extending along a first side edge (26) of the absorbent material (70) and / or at a second side seal in a second side region (34) extending along a second side edge (27) of the absorbent material (70), and wherein a seal strength of each of the channel seals (37, 38) of the absorbent core (21) is higher than a seal strength of each of the first and / or second side seals (33, 34) of the absorbent core (21), said portion preferably comprising at least one of the transverse segments.

5. 5. An absorbent core according to any one of claims 1 to 4, wherein the seal strength of the channel seals (37, 38) is 2.5 N / 25 mm or more, and / or, when combined with claim 4, the seal strength of the first and second side seals (33, 34) is 2.0 N / 25 mm or less.

6. 4. The absorbent core according to claim 1, wherein in at least a portion of the absorbent core (21), in a portion of the absorbent core (21) extending transversely beyond the first channel seal (37) to a first side edge (71) of the absorbent core (21) and / or in a portion of the absorbent core (21) extending transversely beyond the second channel seal (38) to a second side edge (72) of the absorbent core (21), the upper core cover layer (24) and the lower core cover layer (23) are free to seal against each other, said portion preferably comprising at least one of said transverse segments.

7. An absorbent article (1) comprising an absorbent core (21) according to any one of claims 1 to 6.

8. 8. The absorbent article (1) according to claim 7, wherein in at least a portion of the absorbent article, the absorbent article comprises a first edge seal (41) and / or a second edge seal (41), said first edge seal (41) extending along and directly adjacent to a first side edge (26) of the absorbent material (70) and said second edge seal (41) extending along and directly adjacent to a second side edge (27) of the absorbent material (70), said portion preferably comprising at least one of said transverse segments.

9. 9. The absorbent article (1) of claim 8, wherein a sealed width (Ws) is the transverse distance between the first edge seal (41) and the second edge seal (41), and wherein the upper core cover layer (24) and the lower core cover layer (25) of the absorbent core extend across a mutual width which is a core width (Wc), and wherein the sealed width (Ws) is greater than the core width (Wc).

10. An absorbent article (1) comprising an absorbent core (21), said absorbent core (21) having a length in a longitudinal direction (L) and a width in a transverse direction (T), said transverse direction (T) being perpendicular to said longitudinal direction (L); The absorbent core (21) includes an upper core cover layer (24) and a lower core cover layer (25), and an absorbent material (70) sandwiched between the upper core cover layer (24) and the lower core cover layer (25); The absorbent core (21) includes a pair of channels (35, 36) extending in the longitudinal direction in the absorbent material (70); each of the one or more channels (35, 36) being free or substantially free of absorbent material and having a channel seal (37, 38) extending therethrough; the channel seals (37, 38) join the upper and lower core cover layers (24, 25) within the channels (35, 36) and have a longitudinal channel seal length (Ls); the absorbent core (21) is divided along the channel seal length (Ls) into an imaginary set of one or more adjacent transverse segments; Each transverse segment has a segment length of 10 mm and includes said channel seals (37, 38); the set includes a maximum number of segments possible along the channel seal length (Ls); In at least a portion of the absorbent article comprising at least one segment from the set of segments, The absorbent article comprises a first edge seal (41) and a second edge seal (41), the first edge seal (41) extending along and immediately adjacent a first side edge of the absorbent material (70), and the second edge seal (41) extending along and immediately adjacent a second side edge of the absorbent material (70); An absorbent article (1), wherein the sealed width (Ws) is the transverse distance between the first edge seal (41) and the second edge seal (41), and wherein the upper core cover layer (24) and the lower core cover layer (25) of the absorbent core extend across a mutual width which is a core width (Wc), and wherein the sealed width (Ws) is greater than the core width (Wc).

11. The absorbent article comprises one or more additional upper layers (22) above the upper core cover layer (24) and one or more additional lower layers (23) below the lower core cover layer (25); and / or 11. The absorbent article of claim 9 or 10, wherein the first and second edge seals (41) are joined between one of the additional upper layers (22) and one of the additional lower layers (23), or the first and second edge seals (41) are joined between one of the additional upper layers (22) and the lower core cover layer (25), or the first and second edge seals (41) are joined between one of the additional lower layers (23) and the upper core cover layer (24).

12. The absorbent article according to claim 11, wherein said one of said additional upper layers comprises a liquid permeable topsheet (2).

13. 13. The absorbent article according to claim 11 or 12, wherein said one of said additional lower layers comprises a liquid barrier layer (23).

14. 14. The absorbent article according to any one of claims 9 to 13, wherein said edge seals (41) and said channel seals (37, 38) are adhesive seals, weld seals or a combination of adhesive seals and weld seals.

15. 15. The absorbent article of claim 14, wherein the first edge seal (41), the second edge seal (41) and each channel seal (37, 38) are adhesive seals.

16. An absorbent core as claimed in any one of claims 1 to 6 or an absorbent article as claimed in any one of claims 7 to 15, wherein in at least one said segment, a third width (W3) as measured between the channel seals (37) and (38) of the absorbent core (21) is between 20 mm and 60 mm, such as between 25 mm and 45 mm.

17. 17. An absorbent core or article according to any one of claims 1 to 16, wherein in at least one of said segments, said absorbent material (70) has an absorbent width (Wa), said upper core cover layer (24) and said lower core cover layer (25) extend across a mutual width which is a core width (Wc), said absorbent width (Wa) being less than or equal to said core width (Wc).

18. 18. An absorbent core or article according to claim 17, wherein the absorbent width (Wa) is 90% or more of the core width (Wc), for example 95% to 100% of the core width (Wc).

19. 19. An absorbent core or article as claimed in claim 17 or 18, wherein the third width (W3) is in the range of 15% to 40% of the absorbent width (Wa), such as in the range of 20% to 35% of the absorbent width (Wa).

20. 20. An absorbent core or article according to any one of the preceding claims, wherein said pair of channels (35, 36) are straight and extend parallel to said longitudinal direction.

21. 21. An absorbent core or article according to any one of claims 1 to 20, wherein the length of each of the pair of channels (35, 36) is in the range of 50 mm to 500 mm and / or the length of the channel seals (37, 38) is in the range of 50 mm to 500 mm.

22. 22. An absorbent core or article according to any one of the preceding claims, wherein the upper and lower core cover layers (24, 25) are made of a nonwoven material.

23. 23. An absorbent core or article according to any one of the preceding claims, wherein the absorbent material (70) comprises or consists of cellulose pulp fibres and superabsorbent material.

24. 24. The absorbent core or article of claim 23, wherein said superabsorbent material is present in said absorbent material in an amount of from 5% to 80% by weight of said absorbent material (70).

25. 25. An absorbent core or article according to any one of the preceding claims, wherein the absorbent material between the channel seals (37) and (38) has a basis weight in the range of 500gsm to 1200gsm.

26. 26. An absorbent core or article according to any one of the preceding claims, wherein the first and second core cover layers (24, 25) are formed from a single continuous cover material wrapped around the absorbent material (70).

27. 27. An absorbent core or article according to any one of the preceding claims, wherein said upper core cover layer (24) and said lower core cover layer (25) are separate core cover layers.

28. 28. An absorbent core or article according to any one of the preceding claims, wherein the absorbent material (70) has an hourglass or T-shape in a plane defined by the longitudinal direction (L) and the transverse direction (T).

29. 29. An absorbent core or article as claimed in any one of the preceding claims, wherein the absorbent material (70) has a rectangular shape with side edges (26, 27) extending in the longitudinal direction (L) and end edges (28, 29) extending in the transverse direction.

30. 30. An absorbent core or absorbent article as claimed in any one of claims 1 to 29, wherein the absorbent core (21) comprises a central part (51) which, when viewed in the longitudinal direction (L), is arranged between a first end part (52) of the absorbent core (21) and a second end part of the absorbent core (21), and wherein the pair of channels (35, 36) are at least partially, for example completely, arranged in the central part (51) of the absorbent core (21).

31. 31. An absorbent core or article according to claim 30, wherein the central part (51) has a thickness greater than the thickness of the first end part (52) and greater than the thickness of the second end part (53).

32. 32. An absorbent core or article according to claim 31, wherein the central part (51) of the absorbent core (21) has a uniform thickness, and wherein each of the first end part (52) and the second end part (53) of the absorbent core (21) has a uniform thickness, and wherein the central part (51) of the absorbent core (21) is separated from each of the first end part (52) and the second end part (53) by corresponding first transition zones (54) and second transition zones (55).

33. 33. An absorbent core or article according to claim 32, wherein the first end part (52) is a front end part (52), the first transition zone (54) is a front transition zone (54) having an extension in the longitudinal direction (Lc) of 5 mm to 30 mm, and the second end part (53) is a rear end part (53) and the second transition zone (55) is a rear transition zone (55) having an extension in the longitudinal direction (Lc) of 20 mm to 80 mm.

34. 34. An absorbent core or article according to claim 32 or 33, wherein the ratio of the thickness of the central part (51) of the absorbent core (21) to the thickness of the first end part (52) is in the range of 4 to 1.

5.

35. 35. An absorbent core or article according to any one of claims 32 to 34, wherein the ratio of the thickness of the central part (51) of the absorbent core (21) to the thickness of the second end part (53) is in the range of 4 to 1.

5.

36. 36. An absorbent core or article according to any one of claims 32 to 35, wherein in the absorbent core (21), at least two of the central part, the first end part and the second end part (51, 52, 53) have different absorbent capacities.

37. 37. An absorbent core or article according to any one of claims 1 to 36, wherein the absorbent core has a length determined as the distance between a point on a first end edge (28) where the first end edge (28) intersects with a longitudinal centre line (Lc) and a point on a second end edge (29) where the second end edge (29) intersects with the longitudinal centre line (Lc), said length of the absorbent core (21) being in the range of 300 mm to 700 mm.

38. 38. An absorbent core or absorbent article according to any one of claims 1 to 37, wherein at least one of the transverse segments of the absorbent core comprises at least a quarter of the segments in the set of segments, such as at least half of the segments in the set of segments, or all of the segments in the set of segments.

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