Absorbent core having channels, and absorbent article equipped with 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 including an upper core cover layer and a lower core cover layer, and an absorbent material sandwiched between the upper core cover layer and the lower core cover layer. The absorbent article includes 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 channel. The present disclosure further relates to an absorbent article including the absorbent core.

Background Art

[0002] In disposable absorbent products, such as baby diapers and other products for absorbing bodily fluids, including absorbent pants, incontinence protectors, and sanitary napkins, there is a conflict between the requirements for sufficient absorbency and leak prevention and the wearer's comfort and discretion. Therefore, there is a demand for highly absorbent products that are not bulky, flexible, and conform well to the wearer's body. It is highly desirable that the wearer does not feel restricted or uncomfortable while wearing the absorbent product, and that they are confident that the product is effective in preventing leaks. For adult users, it is particularly important that the pants-type garment resembles regular underwear as closely as possible and can be worn discreetly under regular tight-fitting clothing. To provide sufficient absorbency while being thin, the majority of absorbent materials can be superabsorbent materials, or simply what is commonly known as "superabsorbent material." Superabsorbent materials can be combined with absorbent fibers (primarily cellulose pulp fibers) to create a fibrous network, which helps distribute liquid within the absorbent core and retain particulate superabsorbent material within the core. Superabsorbent materials are polymer materials typically incorporated into absorbent articles in the form of fibers, particles, or granules. When superabsorbent materials swell to form a hydrogel, they can absorb many times their own weight in fluid. Absorbent articles containing large amounts of superabsorbent material have been found to lose their initial flexibility and wearer comfort as they absorb liquid and swell. High-impact areas of absorbent articles (e.g., the crotch area of ​​a diaper containing a large amount of absorbent material distributed over a relatively small area) can become thicker and harder as the article absorbs liquid. Furthermore, in disposable absorbent articles, it is important that the available absorbent capacity of the absorbent material be utilized as fully as possible to minimize material consumption when producing the absorbent articles. Therefore, it is desirable that the entire absorbent capacity of the superabsorbent material be utilized.It has been proposed to provide further stabilization of 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 having no cellulose fibers at all.

[0003] Patent Document 1 proposes stabilizing an absorbent core and preventing sagging in the crotch area of ​​an absorbent article by forming two longitudinally extending channel sealings within the absorbent core. The absorbent core is enclosed within a core cover, and the channel sealings are arranged to join the upper and lower sides of the core cover, dividing the absorbent core into a central segment and two lateral segments. When the absorbent material within the absorbent core absorbs bodily fluids and swells, the core cover acts as a swelling limiting means by restricting the swelling space for the absorbent material in the different segments. Thereafter, the expanding absorbent material exerts outward pressure on the core cover, resulting in an increase in the rigidity of the absorbent core in the crotch area of ​​the absorbent article. In particular, high rigidity can be achieved therein within 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 [Overview of the Initiative] [Means for solving the problem]

[0005] This disclosure is based on the insight that absorbent articles having improved fit, body conformity, and wearer comfort, as well as good absorbency and leak-proof properties, can be achieved by the features of claim 1, or alternatively, by the features of claim 10, at least in part. Variations of this disclosure are described in the dependent claims and the following description.

[0006] The absorbent articles referred to herein may be wearable disposable absorbent articles in the form of, for example, open diapers, pull-up diapers, belted diapers, incontinence clothing, and women's sanitary clothing, as well as disposable absorbent inserts, such as incontinence shields or sanitary napkins, which are worn inside support clothing (for example, support pants or regular underwear). These articles are used to absorb, distribute, and store various types of bodily exudates while providing the wearer with a high level of comfort and a dry feeling during wear.

[0007] In a first embodiment, the disclosure relates to an absorbent core having a length in the longitudinal direction and a width in the 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 core cover layer and the lower core cover layer. The absorbent core includes a pair of channels extending longitudinally in the absorbent material. Each channel has a channel seal extending therein, which is either absent or substantially absent from the absorbent material, and the channel seal joins the upper and lower core cover layers within the channel and extends along the longitudinal channel seal length. The absorbent core is divided along the channel seal length into one or more bordering transverse segments, each transverse segment having a segment length of 10 mm and including a channel seal. The set includes the maximum possible number of segments along the channel seal length. Furthermore, the absorbent core has such that, with respect to at least one transverse segment of the 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, with the first width being 120% or more of the second width. The first and second widths of the core cover layer are the widths of the core cover layer between the channel seals in the unfolded, completely flat state.

[0008] During use of an absorbent article containing an absorbent core as described above, the absorbent material of the absorbent core will absorb bodily fluids and swell. The channel seals joining the upper and lower core cover layers in the channel act as limiting means, which limit the swelling of the absorbent material transversely and in the thickness direction by preventing the upper and lower core cover layers from moving freely apart from each other. However, if one of the upper and lower core cover layers has a first width between the channel seals and the other of the upper and lower core cover layers has a second width between the channel seals, and the first width is 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 absorbent capacity of the absorbent material.

[0009] The channel seal prevents separation of the upper and lower core cover layers, thereby limiting the swelling of the absorbent material near the channel. The channel seal is preferably a permanent seal, or at least a large portion of each channel seal is a permanent seal that will not rupture under normal use and handling of the absorbent article. For example, the channel seal can be an adhesive seal, a welded seal, or a combination of an adhesive seal and a welded seal.

[0010] The seal strength of a channel seal can be, for example, 2.5 N / 25 mm or more, or for example, 3 N / 25 mm or more, when measured according to the test methods disclosed herein. There is no upper limit to the seal strength of a channel seal, since the only requirement for a channel seal is that it does not break under the pressure that may be applied to the seal during normal use.

[0011] Prior to the present invention, it should be understood that 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. Therefore, by providing a core cover having a first width between channels on one side of the core cover layer and a second width between channels on the other side of the core cover layer that is different from the first width, an improved utilization of the absorption capacity of the absorbent material 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 increase in space for the absorbent material, such as that provided between the channel seals and separated by the core cover layer, will provide an improved swelling capacity, mainly in the thickness direction of the absorbent core.

[0012] Therefore, an absorbent core with improved absorption capacity can be realized without increasing the width of the absorbent core (the relative width of the upper and lower core cover layers), which is beneficial for the comfort and fit of the absorbent article containing the absorbent core.

[0013] The first width should be at least 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 the range of 120% to 160% of the second width, for example, in the range of 130% to 160% or 135% to 160% of the second width.

[0015] Optionally, in at least one of the transverse segments, the first width differs from the second width by only 3 mm or more, for example, by 5 mm 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 directly on the absorbent core in its dry, pre-use state. (In other words, the third width should not be measured in an unfolded state, as with the first and second widths.)

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

[0019] In at least one of the transverse segments, the upper core cover layer and the lower core cover layer extend over a mutual width which is the core width as defined herein.

[0020] Therefore, the first and second longitudinal side edges of the absorbent core are considered to be longitudinal side edges that separate the widths of the upper core cover layer and the lower core cover layer from each other.

[0021] In some examples, in at least one of the transverse segments, the upper core cover layer and the lower core cover layer may have the same width, in which case this width is the core width.

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

[0023] The absorbent width can be smaller than the core width in at least one of the transverse segments. Thus, the upper and lower core cover layers have a mutual extension over the entire absorbent width and surround the absorbent material.

[0024] Optionally, in at least one of the segments, the absorbent width can be substantially equal to the core width.

[0025] Due to the first width being larger than the second width, which allows an increase in the 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 an improved swelling capacity.

[0026] For example, in at least one of the segments, the absorbent width can be 90% or more of the core width, for example, it can be from 90% to 100% of the core width. For example, the absorbent width can be from 95% to 100% of the core width.

[0027] As described above, the absorbent core has a third width in at least one of the segments, and the third width is 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 absorbent width, for example, it can be in the range of 20% to 35% of the absorbent width.

[0029] Two channels of a pair of channels can be symmetrically arranged and extend at intervals on each side of the longitudinal center line of the absorbent material. Thus, each channel can extend between the longitudinal center line and the corresponding one of the first side edge or the second side edge of the absorbent material.

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

[0031] In some examples, two of a pair of channels are linear and extend parallel to the longitudinal direction.

[0032] In some cases, the absorbent core may contain two or more pairs of channels. Each pair of channels may extend, for example, across separate longitudinal portions of the absorbent core.

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

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

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

[0036] The basis weight of core cover materials used in this specification is, for example, 5 g / m². 2 From 20g / m 2 It is possible to be within the range.

[0037] The core cover material can be made from thermoplastic polymer materials (e.g., polyolefins, polyesters, polyamides, and combinations thereof). The core cover material can be nonwoven fabric, perforated plastic film, mesh, etc. The nonwoven layer can be formed by any of the various different processes known in the art (e.g., spunbond process, airlaying process, meltblown process, or bonded carded web formation process). The nonwoven layer can be made from co-formed laminas of nonwoven materials (e.g., SMS (spunbond / meltblown / spunbond) nonwoven fabric, SMMS (spunbond / meltblown / meltblown / spunbond) nonwoven fabric, or SS (spunbond / spunbond) nonwoven fabric). The thermoplastic polymer material in the nonwoven layer can be polypropylene, or a two-component fiber of polypropylene and polyethylene, or a combination of such materials.

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

[0039] The absorbent material may include or be composed of cellulose pulp fibers and superabsorbent materials.

[0040] The absorbent material may contain superabsorbent material, preferably 5% to 80% by weight of the absorbent material being superabsorbent material. For example, the absorbent material may contain 30% to 80% by weight of superabsorbent material.

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

[0042] Absorbent materials can consist of a single absorbent component layer. Absorbent materials comprising two or more layers are also intended for absorbent articles such as those disclosed herein.

[0043] Superabsorbent materials can be polymer materials and can exist in the form of particles, granular fibers, flakes, etc.

[0044] The relatively high amount of superabsorbent material within the absorbent core allows for the production of thin, individual absorbent articles while providing high absorption capacity and the ability to chemically bind absorbed fluids (resulting in absorbent articles with high leak-proof properties and a dry inner surface even after absorbing large amounts of fluid). Articles containing thin superabsorbent material also have pre-use advantages, as they occupy less space for packaging, transport, and storage, as well as on store shelves.

[0045] For example, the absorbent material between the channel seals can 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 material layer, the single material layer 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 a plane defined by the longitudinal and transverse directions. For example, the absorbent core can have an hourglass shape or a T-shape in a 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] An absorbent core may include two or more parts having different absorption capacities. The absorbent core may be a core with a three-dimensional shape and contour, where the central part of the absorbent core is located between the first end part and the second end part of the absorbent core when viewed in the longitudinal direction, and the central part of the absorbent core has 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 may have a uniform first thickness, the first end part may have a uniform second thickness, and the second end part may have a uniform third thickness. The first thickness may be equal to the second thickness. The central part of the absorbent core may be separated from the first end part and the second end part, respectively, by corresponding first and second transition zones.

[0052] The first end part may be a front end part, and the first transition zone may be a front transition zone having a longitudinal extension of 5 to 30 mm (for example, 10 to 20 mm), and the second end part may be a rear end part, and the second transition zone may be a rear transition zone having a longitudinal extension of 20 to 80 mm (for example, 30 to 60 mm). The thickness of the absorbent core preferably changes 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 absorbent articles such as those 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 the first end edge of the absorbent core where the first end edge intersects the longitudinal centerline and a point on the 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 to 700 millimeters (for example, in the range of 350 to 600 millimeters, or in the range of 400 to 500 millimeters).

[0056] In an absorbent core having a thickened central part, the thickened central part can have a length on the order of 30% to 70% of the length of the absorbent core (for example, a length on the order of 40% to 60% of the length of the absorbent core, or a length on the order of 45% to 55% of the length of the absorbent core). The length of the thickened central part can be approximately half the length of the absorbent core.

[0057] The absorbent core in an absorbent article as disclosed herein may have any planar shape (e.g., rectangular, T-shaped, or hourglass shape). The hourglass shape includes all configurations of a core in which the end parts are wider than the central part. Planar shapes in which the central part is narrower than the end parts may be preferable to the rectangular shape because the narrower central part can fit more comfortably in the wearer's crotch. Furthermore, the narrow central part of the absorbent core can allow for greater transverse expansion of the core during use of the absorbent article without causing discomfort.

[0058] An absorbent core as disclosed herein may include a three-dimensional core having a thicker central part and thinner end parts, the core being surrounded by a core cover including an upper layer and a lower layer. The upper and lower layers 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 located therein (for example, two sealed channels symmetrically arranged on each side of a centerline extending in the longitudinal direction of the article). The upper and lower layers of the core cover are bonded to each other by channel seals located within the channels. The upper and lower layers are in contact with each other in lateral regions extending along the lateral edges of the absorbent core. One or more channels are devoid of absorbent material, meaning that the upper and lower layers of the core cover are directly bonded to each other in the channel seals. Furthermore, the absorbent core can also be molded in a planar shape, for example, having an hourglass shape in which the central part of the absorbent core is narrower than the first and second end parts.

[0059] In an absorbent core with a three-dimensional shape as disclosed herein, the thinner end parts may have a uniform or substantially uniform thickness, and the thicker central part may have a uniform or substantially uniform thickness. A transition zone may 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 within the transition zone. The end parts may be a designated front end part and a designated rear end part, the rear end part having a greater extension in the longitudinal direction of the absorbent article than the front end part. The rear transition zone may have a greater extension in the longitudinal direction of the absorbent article than the front transition zone, as disclosed herein.

[0060] A pair of channels can be positioned at least partially (for example, completely) 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. The portion preferably includes at least one transverse segment.

[0062] Side seals can be permanent seals, i.e., they can be intended to remain intact during use of the absorbent core. However, in this example, the sealing strength of the channel seals of the absorbent core can be higher than the sealing strength of the first and second side seals of the absorbent core, respectively. 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 the thickness-direction swelling of the absorbent core near the channels. The channel seals are preferably permanent seals, or at least a large portion of each channel seal is a permanent seal that does not break under normal use and handling of the absorbent article. Permanent seals resist the forces arising from the swelling absorbent material in the absorbent core and remain intact throughout the use of the absorbent article. Side seals are breakable seals that break under the influence of the forces exerted on the side seals as the absorbent material in the absorbent core absorbs fluid and expands. Breakable side seals, along with channel seals, primarily promote the expansion of absorbent material in the lateral or transverse direction of the absorbent core and absorbent article.

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

[0064] In other examples, in at least a portion of the absorbent core, the upper core cover layer and the lower core cover layer are not sealed to each other in the portion of the core that extends transversely beyond the first channel seal to the first side edge of the absorbent core, and in the portion of the core that extends 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 core cover layer and the lower core cover layer in the first side region extending along the first side edge of the absorbent material, and in the second side region extending along the second side edge of the absorbent material. The portion of the absorbent core preferably includes at least one of the transverse segments.

[0065] As will be further explained below with respect to absorbent articles containing such absorbent cores, the absence of a seal between the upper core cover layer and the lower core cover layer on the outer side of the side edge of the absorbent material allows for swelling of the absorbent material in each transverse direction on the outer side of the core width, and thus further improves the utilization of the absorbent capacity of the absorbent material.

[0066] Accordingly, an absorbent core as disclosed herein may include an upper core cover layer and a lower core cover layer sandwiching an absorbent material. The core may include a pair of sealed channels located therein (for example, two sealed channels symmetrically arranged on each side of a centerline extending in the longitudinal direction of the article). The upper and lower layers of the core cover are joined to each other by a channel seal, which is located within one or more channels and extends along the longitudinal channel seal length. The pair of channels are without absorbent material, meaning that the upper and lower layers of the core cover are directly joined to each other in the channel seal. The absorbent core is divided into one or more hypothetical sets of 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 possible number of adjacent segments along the channel seal length.

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

[0068] An absorbent core as disclosed herein may include a three-dimensional core material having 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 (e.g., two sealed channels symmetrically arranged on each side of a centerline extending longitudinally in the article) located therein and extending along the longitudinal channel seal length. The upper and lower layers of the core cover are joined to each other by a channel seal located within one or more channels. The pair of channels are without absorbent material, meaning that the upper and lower layers of the core cover are directly joined to each other in the channel seal. The absorbent core is divided into one or more hypothetical sets of 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 possible number of adjacent segments along the channel seal length. The absorbent core has such that, with respect to at least one transverse segment of the 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, and the first and second widths of the core cover layer are the widths of the core cover layer between the channel seals in the unfolded, completely flat state, and the first width is 120% or more of the second width. For example, 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, at least one transverse segment can include all of the segments in the set of segments.The fact that the second width is greater than the first width means that space is provided for the expansion of the absorbent material positioned transversely between the channels, primarily enabling the expansion of the absorbent material between the channels in the thickness direction of the absorbent core. The absorbent core can also be molded in a planar shape, for example, having an hourglass shape in which the central part of the absorbent core is narrower than the first and second end parts. Optionally, the upper and lower core cover layers may not seal each other in portions of the core extending transversely beyond the first channel seal toward the first side edge, and in portions 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 in these portions means that the absorbent material positioned transversely outside the pair of channels on each side of the absorbent core can extend in their respective transverse directions without being restricted by such seals. For example, the absorbent material can expand transversely beyond the mutual extension of the upper and lower core cover layers.

[0069] In an absorbent core with a three-dimensional shape as disclosed herein, the thinner end parts may have a uniform or substantially uniform thickness, and the thicker central part may have a uniform or substantially uniform thickness. A transition zone may 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 within the transition zone. The end parts may be a designated front end part and a designated rear end part, the rear end part having a greater extension in the longitudinal direction of the absorbent article than the front end part. The rear transition zone may have a greater extension in the longitudinal direction of the absorbent article than the front transition zone, as disclosed herein.

[0070] In a second embodiment, an absorbent article is provided that includes an absorbent core according to the first embodiment.

[0071] The absorbent article may include, in at least a portion thereof, 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 portion of the absorbent article may preferably include at least one of the segments.

[0072] The phrase "directly adjacent" means 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. Therefore, the first or second edge seal is the first seal that the absorbent material can reach when expanding transversely. Thus, the first and second edge seals form a seal that limits 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 the first edge seal and the second edge seal, and the upper and lower core cover layers of the absorbent core extend across their respective widths, which is the core width, then the sealed width can be greater than the core width.

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

[0075] Therefore, the fact that the sealed width is 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 can expand outside the core width in the transverse direction. Consequently, the absorbent article provides additional space for the swelling of the absorbent material beyond the limited core width.

[0076] Advantageously, in an absorbent article, the absorbent core may have an upper core cover layer and a lower core cover layer that are not sealed to each other, as described above, in portions of the core that extend transversely beyond the first channel seal toward the first side edge of the absorbent core, and in portions of the core that extend transversely beyond the second channel seal toward the second side edge of the absorbent core. Thus, in this example, the absorbent core lacks a side seal connecting the upper core cover layer and the lower core cover layer, and therefore the first and second edge seals extend directly adjacent to the first and second side edges of the absorbent material, respectively.

[0077] The absence of a side seal in the absorbent core further implies the possibility of 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 friction 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 one or more additional lower layers below the lower core cover layer.

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

[0080] For example, the first and second edge seals can be joined between one of the additional upper layers and the lower core cover layer.

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

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

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

[0085] As stated above, the first and second edge seals can be permanent seals. That is, the sealing strength of the first and second edge seals is such that they do not break under the pressure that may be applied to the seals during normal use. Therefore, there is no upper limit to the sealing strength of the edge seals.

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

[0087] For example, the sealing strength of a channel seal can be 2.5 N / 25 mm or more, as illustrated above.

[0088] The seal strength of the edge seal can be 2.5 N / 25 mm or more in some variations. However, in other variations, the seal strength of the edge seal can be 1 N / 25 mm or more.

[0089] For example, edge seals and channel seals can be adhesive seals, welded seals, or a combination of adhesive and welded seals. The seal may be formed as a continuous bonding line, or it may be formed by individual bonding elements arranged along the seal.

[0090] Welded seals can include heat-welded seals and other types of welded seals (e.g., ultrasonically welded seals). With respect to welded seals (e.g., heat-welded seals and ultrasonically welded seals), the seal strength can be controlled by changing parameters (e.g., seal temperature, energy supply, seal time, and seal pressure) and / or by changing the seal pattern.

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

[0092] In this example, the edge seals can be adhesive seals, and the basis weight of the adhesive in each edge seal is 2 g / m².2 (For example, 3 g / m²) 2 or more, or 5g / m² 2 It is possible for it to be the above (and so on).

[0093] In absorbent articles as disclosed herein, the absorbent article may include a liquid-permeable top sheet and a liquid barrier layer, with an absorbent core positioned between the liquid-permeable top sheet and the liquid barrier layer. The liquid-permeable top sheet and liquid barrier layer are provided in addition to an upper core cover layer and a lower core cover layer. For example, the upper core cover layer may face the liquid-permeable top sheet, and the lower core cover layer may face the liquid barrier layer.

[0094] An absorbent core comprising a liquid-permeable top sheet, a liquid barrier layer, and a core cover may be part of or constitute an absorbent assembly or “core pack,” which is produced as a separate unit and subsequently 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 described above, an article comprising a combination of absorbent cores, wherein in at least one segment, one of the lower core cover layer and the upper core cover layer has a first width between channel seals, and the other of the lower core cover layer and the upper core cover layer has a second width between channel seals, where the first and second widths of the core cover layer are the widths of the core cover layer between channel seals in an unfolded, fully flat state, the first width is 120% or more of the second width, the sealed width is the transverse distance between the first edge seal and the second edge seal, the upper and lower core cover layers of the absorbent core extend over each other's width which is the core width, and the sealed width is greater than the core width, the article provides additional space for swelling of the absorbent material over a predetermined core width. Preferably, the article may be configured such that the sealed width is greater than the core width over at least a portion of the article comprising at least one of the segments.

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

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

[0098] Therefore, in an alternative embodiment, an absorbent article is provided comprising an absorbent core, wherein the absorbent core has a length in the longitudinal direction and a width in the transverse direction perpendicular to the longitudinal direction. The absorbent core comprises an upper core cover layer and a lower core cover layer, and an absorbent material sandwiched between the upper core cover layer and the lower core cover layer, and also comprises a pair of channels extending longitudinally in the absorbent material. Each of the one or more channels has a channel seal extending therein, which is either absent or substantially absent from the absorbent material. The channel seal joins the upper and lower core cover layers within the channel and extends along the longitudinal channel seal length. The absorbent core is divided along the channel seal length into one or more hypothetical sets of adjacent transverse segments, each transverse segment having a segment length of 10 mm and including a channel seal. The set comprises the maximum possible number of adjacent segments along the channel seal length. The absorbent core is an absorbent article comprising at least one segment from a set of segments, wherein the absorbent article includes 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 lower core cover layer of the absorbent core extending over their respective widths which is the core width, the sealed width being greater than the core width.

[0099] Therefore, as described above, in alternative embodiments of absorbent articles, the sealed width is greater than the core width, meaning 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 transversely outward of the core width. Thus, the absorbent material is capable of expanding transversely outward of the core width. Consequently, the absorbent article provides additional space for the swelling of the absorbent material beyond the limited core width.

[0100] An alternative embodiment of the absorbent article can be combined with any one of the features 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] Absorbent cores and / or absorbent articles as disclosed herein can be modified within the scope of the appended claims. For example, the materials and dimensions used for the different layers forming the absorbent cores and / or absorbent articles as disclosed herein can be modified as shown above. The absorbent articles may further include any useful components or features known in the art, such as fluid acquisition and distribution components, leg elastics, standing gathers, crotch and waist elastics, side panels, tightening systems, wetness indicators, skincare agents, waste disposal means, etc., depending on the type of absorbent article intended and as known in the art.

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

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

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

[0105] Optionally, any of these features may be applicable to all segments in a set of segments, i.e., at least one transverse segment includes all segments in the set of segments.

[0106] As described above, a set of segments can contain 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). Therefore, the number of segments in a set will correspond to the longitudinal channel seal length divided by 10 mm and rounded down to the nearest integer.

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

[0108] As used herein, the term "width" refers to the maximum width measured in the transverse direction of the absorbent core or article.

[0109] As used herein, the term “length” refers to the maximum length measured along the longitudinal direction of the absorbent core or article.

[0110] Unless otherwise explicitly stated, width and length should be measured directly on the absorbent core or article in the condition as it is provided before use by the wearer.

[0111] The term "thickness direction" refers to the direction perpendicular to the transverse and longitudinal directions.

[0112] As used herein, the terms “upper” and “lower” refer to two opposing directions along the thickness dimension (i.e., perpendicular to the transverse and longitudinal directions). Therefore, such terms do not imply any particular orientation in the vertical direction. Furthermore, such terms do not imply that, at the time of use, the absorbent core or article should have any particular orientation relative to the user. [Brief explanation of the drawing]

[0113] [Figure 1] This is a plan view of a stretched absorbent pant-type article, as seen from the inner surface of the pant-type article, with an absorbent assembly and open side seams. [Figure 2]This is a magnified view of the absorbent assembly inside the pants-type article shown in Figure 1, where the absorbent material is enclosed within the core cover. [Figure 3a] This figure shows a cross-section taken along line III-III, passing through the version of the absorbent core shown in Figure 2, when the absorbent core is in a dry state. [Figure 3b] This is a diagram showing a cross-section through another version of the absorbent core. [Figure 4a] This figure shows a cross-section of the absorbent assembly shown in Figure 2, taken along line III-III, when the absorbent core is in a dry state. [Figure 4b] This figure shows a cross-section of the absorbent assembly shown in Figure 2, taken along line III-III, when the absorbent core is in a wet state. [Figure 5] This figure shows a cross-section taken along line III-III, passing through another modified example of the absorbent assembly shown in Figure 2, when the absorbent core is in a dry state. [Figure 6] This figure shows the pant-type item as it appears before use, with the side seams closed and not stretched. [Figure 7] This figure shows how the test specimen is mounted in the clamp of the test apparatus in order to carry out the seal strength test method as described herein. [Figure 8] This figure shows how the test specimen is mounted in the clamp of the test apparatus in order to carry out the seal strength test method as described herein. [Figure 9] This figure shows the portions of the first core cover layer and the second core cover layer when they are in the unfolded state. [Figure 10] This diagram shows how the test specimen is mounted in order to perform width measurement in the unfolded state. [Figure 11] This is a schematic diagram of a method as disclosed herein. [Figure 12]This is a top view of the first core cover web applied to a mat-forming surface in a prior art method. [Figure 13] This figure shows a cross-section taken along line III-III, passing through the first core cover web and mat-forming surface in Figure 12. [Figure 14] This is a top view of a first core cover web applied to a mat-forming surface in a method as disclosed herein. [Figure 15] This figure shows a cross-section taken along line VV, passing through the first core cover web and mat-forming surface in Figure 14. [Modes for carrying out the invention]

[0114] Different aspects of this disclosure will be described in full hereafter with reference to the accompanying drawings. The embodiments disclosed herein can be realized in many different forms and should not be construed as being limited to the embodiments described herein. Although the absorbent articles shown in the figures are panty-type articles, it should be understood that absorbent cores, such as those described in the examples, can be used in any disposable absorbent articles for absorbing urine, feces, and / or vaginal secretions, as disclosed herein.

[0115] The drawings are schematic, and individual components (such as layers of material) are not necessarily drawn to scale.

[0116] The pant-type article shown in the figure is a simplified article, and the article may include further features (e.g., barrier cuffs). It should also be understood that the waist elastic material disclosed herein is optional, or any other suitable type of waist elastic material may be used. The side seams may be re-closable side seams, and the pant-type article may be provided with fastening elements to provide the re-closability of the side seams.

[0117] Referring first to Figure 1, a pant-type incontinence article for adult users, Article 1, is shown. Article 1 is shown in Figure 1 in an unfolded, flat state, with all elastic elements fully extended. Article 1 has a longitudinal direction L and a transverse direction T, where the transverse direction T is perpendicular to the longitudinal direction, and the longitudinal centerline Lc extends in the longitudinal direction L.

[0118] The pants-type article 1 is viewed from the inside surface, which is the surface that will face the wearer's body when the article is being worn, and is on the opposite side of the outer surface of the pants-type article 1 that faces the clothing.

[0119] The pants-type article 1 comprises a front portion 3, a rear portion 4, and an absorbent assembly 20, the absorbent assembly 20 being located in the crotch portion 6 of the pants-type article 1, extending forward over the front portion 3 and backward over the rear portion 4 in the longitudinal direction L. The absorbent assembly 20 extends longitudinally L from the front portion 3 through the crotch portion 6 into the rear portion 4. The absorbent assembly 20 in the pants-type article shown in the figure is a separately produced component including an absorbent core 21, the absorbent core 21 containing an absorbent material 70, the absorbent material 70 sandwiched between an upper core cover layer 24 and a lower core cover layer 25, and further sandwiched between a liquid-permeable top sheet 22 and a liquid barrier layer 23. The absorbent core 21 is positioned between the top sheet 22 and the liquid barrier layer 23, with the upper core cover layer 24 facing the liquid top sheet 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 an absorbent core applied to an article as a component of a prefabricated absorbent assembly that already includes a top sheet and a 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 and 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 and 12 extending in the longitudinal direction L.

[0122] A first front side edge 8 is joined to a first rear side edge 11 at a first side seam 14, and a second front side edge 9 is joined to a second rear side edge 12 at a second side seam 15, producing a pair of pants-type article 1 having a waist opening 16, a first leg opening 17, and a second leg opening 18, as shown in Figure 6.

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

[0124] It is generally desirable that soiled pant-type garments can be easily removed without having to pull the garment down over the user's legs. Therefore, side seams are generally made so that they can be torn by manual force, allowing the user or caregiver to pull the side seams apart before removing the soiled pant-type garment.

[0125] The waist opening 16 is defined by the front panel waist edge 7 and the rear panel waist edge 10. The first leg edge 19' defines the first leg opening 17, and the second leg edge 19'' defines the second leg opening 18.

[0126] Referring to Figure 2, the absorbent material 70 has an hourglass shape with a first side edge 26 and a second side edge 27, a first end edge 28 and a second end edge 29. The first side edge 26 and the second side edge 27 of the absorbent material 70 have a primary extension in the longitudinal direction L, while the first end edge 28 and the second end edge 29 have a primary extension in the transverse direction T.

[0127] The first channel 35 and the second channel 36 are located within the absorbent material 70 and extend in the longitudinal direction L on either side of the longitudinal centerline Lc, and at predetermined distances from the first and second side edges 26 and 27 of the absorbent material 70, respectively. The channels 35 and 36 are either devoid of absorbent material or substantially devoid of absorbent material.

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

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

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

[0131] In a pant-type absorbent article for adult users with incontinence (for example, absorbent article 1 shown in the figure), 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 positioned in the user's crotch 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 excreted bodily fluids (for example, urine). Therefore, the crotch portion 6 must have good absorbent properties in terms of fluid acquisition, fluid distribution, and absorption capacity. The channels 35, 36 in the absorbent material 70 contribute to rapid fluid acquisition and promote fluid distribution by directing the fluid flow toward the front and rear portions 3, 4 of the absorbent article 1. In absorbent article 1 shown in the figure, the length of channels 35, 36 substantially corresponds to the length of the crotch portion 6 and can typically be on the order of 100 to 250 millimeters.

[0132] In wearable incontinence products (e.g., open-type and pull-up diapers), the channel typically has a length on the order of 30% to 50% of the total length of the absorbent core. In smaller absorbent products (e.g., incontinence shields and sanitary napkins), the channel can extend almost to the edge of the absorbent core (e.g., up to 80% of the total length of the absorbent core).

[0133] To enhance the absorbent capacity in the narrow crotch portion 6 of the absorbent article 1, the central part 51 of the absorbent core 21, which is located between the first end part 52 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 and 53. In the absorbent article 1 shown in the figure, 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 end part 52 and second end part 53 of the absorbent core 21 has a uniform thickness, and the central part 51 of the absorbent core 21 is separated from each of the first end part 52 and second end part 53 by corresponding first transition zones 54 and second transition zones 55. The thickness of the absorbent core 21 decreases linearly in the transition zones 54 and 55 from the central part 51 of the absorbent core 21 to the end parts 52 and 53 of the absorbent core 21. The rear end part 53 has a greater extension in the longitudinal direction of the absorbent article 1 than the front end part 52. In the absorbent core 21 shown in Figure 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 forward transition zone may be longer than the backward transition zone. Also, absorbent cores having a thickened central portion and thinner end portions, but without transition zones between different parts of the core, are also intended for absorbent articles as disclosed herein. Furthermore, the central and end portions may have non-uniform thicknesses.

[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 may have the same thickness or may have different thicknesses.

[0137] Furthermore, it should be understood that the three-dimensional shape of the absorbent core is arbitrary for an absorbent article as disclosed herein, and that the absorbent core may be planar or substantially planar. In a planar or substantially planar absorbent core, the absorbent capacity in the absorbent core may differ in different parts of the core as a result of different amounts of superabsorbent material being placed in different parts of the core.

[0138] An absorbent core 21 as disclosed herein may include any absorbent material 70 suitable for absorbing excreted bodily waste, such as cellulose fluff pulp, tissue layers, superabsorbent polymers (superabsorbent materials), absorbent foam materials including hydrogel foam materials, or absorbent nonwoven fabric materials. The absorbent core may also include non-absorbent components (e.g., reinforcing elements, molding elements, binders, etc.). Various types of liquid receiving elements and liquid distributing elements may also be included in the core.

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

[0140] Superabsorbent materials are polymer materials and can exist in the form of particles, granular fibers, flakes, and other materials.

[0141] As disclosed herein, the absorbent core 21 may include a mixture of absorbent cellulose fibers (e.g., cellulose pulp fibers) and a superabsorbent material.

[0142] The large amount of superabsorbent material within the absorbent core allows for the production of thin, individual absorbent articles while providing high absorption capacity and the ability to chemically bind and immobilize absorbed fluids (resulting in absorbent articles with high leak-proof properties and a dry inner surface even after absorbing large amounts of fluid).

[0143] As schematically illustrated in Figure 2, the absorbent core 21 can be divided into one or more hypothetical sets of adjacent transverse segments S1 to S9 along the channel seal length Ls. Each transverse segment has a segment length of 10 mm and includes a portion of the channel seal. One or more sets of transverse segments contain the maximum possible number of adjacent segments along the channel seal length. Thus, 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 Figure 2, a hypothetical set of adjacent transverse segments S1 to S9 is illustrated by a dashed line.

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

[0146] Figure 3a shows the absorbent core 21 in a dry state before it absorbs liquid.

[0147] The absorbent core has a length in the longitudinal direction L, a width in the transverse direction W, and a height in the thickness direction H, where the thickness direction H is 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 core cover layer and the lower core cover layer 25. The absorbent core 21 includes a pair of channels 35, 36 that extend longitudinally in the absorbent material 70, and each of the channels 35, 36 is either devoid of absorbent material or substantially devoid of absorbent material. Each of the channels 35, 36 has channel seals 37, 38 extending therein, which join the upper and lower core cover layers 24, 25 within the channels 35, 36. As can be seen in the cross-sectional view of Figure 3, the upper core cover layer 24 and the lower core cover layer 25 form a space between the channel seal 37 and the channel seal 38, and this space contains an absorbent material 70. During use, the absorbent material 70 absorbs liquid and swells. For example, when the absorbent material 70 contains a superabsorbent material, the superabsorbent material absorbs liquid during the swelling and formation of 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 seen between channel seals 35 and 36, the space for lateral expansion is limited.

[0149] As illustrated in Figure 3a, in order to provide additional space for the swelling of the absorbent material 70 between channel seals 37 and 38, the absorbent core 21 is configured such that the upper core cover layer 24 has a first width W1 when viewed along the upper core cover layer 24 itself, i.e., in an unfolded, completely flat state, and the lower core cover layer 25 has a second width W2 when viewed along the lower core cover layer 25, 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 channel seals 37 and 38 is provided, allowing for increased swelling of the absorbent material 70 between channels 35 and 36 in the thickness direction. The first and second widths W1 and W2 between the channel seal 37 and the channel seal 38 in the unfolded and completely flat state can be determined by a method as described in the following Methods chapter of this application.

[0150] For example, the first width W1 can be different from the second width W2 by at least 3 mm (for example, 5 mm or 7 mm or more).

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

[0152] Alternatively, or in addition to providing additional space for the 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 the swelling of the absorbent material 70 in the laterally outer portions of the channel seals 37 and 38.

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

[0154] Therefore, the first lateral region 33 is a region of the absorbent core 21 that extends transversely beyond the first lateral edge 26 of the absorbent material 70 to the first lateral edge 71 of the absorbent core 21. Similarly, the second lateral region 34 is a region of the absorbent core 21 that extends transversely beyond the second lateral edge 27 of the absorbent material 70 to the second lateral edge 72 of the absorbent core 21. As can be seen in Figure 3a, the first and second lateral edges 71 and 72 of the absorbent core 21 are considered to be edges that separate the mutual extensions 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 in a first side seal extending into a first side region 33 and in a second side seal extending into a second side region 34.

[0156] In the laterally outer portions of the channel seals 37 and 38 (i.e., laterally adjacent to the first and second side regions 33 and 34, respectively), the side seals can be adapted to be ruptureable seals in order to provide additional space for the swelling of the absorbent material 70, that is, they can be intended to rupture under the influence of the force exerted on the side seals when the absorbent material in the absorbent core absorbs fluid and expands. Thus, the channel seals can have a higher sealing strength than the respective sealing strengths of the first and second side seals. For this purpose, for example, the sealing strength of the channel seals can be 2.5 N / 25 mm or more, while the sealing strengths of the first and second side seals can be 2.0 N / 25 mm or less.

[0157] In other variations (for example, those illustrated in Figure 2), the upper core cover layer 24 and the lower core cover layer 23 may not be sealed to each other. Therefore, 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 not be sealed.

[0158] The absence of a seal in the first and second lateral regions 33 and 34 of the absorbent core 21 means that there is no seal that provides significant seal strength. However, the first core cover layer 24 and the second core cover layer 25 can still have some degree of connection (albeit with very low connection integrity), for example, through frictional connections between the cover layer 24 and the cover layer 25.

[0159] As shown in the example in Figure 3a, when there is no side seal 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 and 36 can therefore swell transversely beyond the extension of the core width Wc, i.e., beyond the mutual extension of the core cover layers 24 and 25.

[0160] As illustrated in Figure 3a, the absorbent material 70 can have an absorbent width Wa, as seen in the transverse section of the core. In the transverse section, the upper core cover layer 24 and the lower core cover layer 25 extend across their respective widths, which is the core width Wc.

[0161] The absorbent material width Wa is smaller than the core width Wc. With respect to the absorbent material between channel seals and / or with respect to the absorbent material in the transversely outer portion of the channel seal, the core width Wc can be relatively narrower due to the increased space for the swelling of the absorbent material 70 which may be provided as described above. Thus, the absorbent material width Wa can be 90% or more of the core width Wc (for example, 95% or more of the core width Wc).

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

[0163] Figures 4a and 4b show cross-sections taken along line III-III through the absorbent assembly of Figure 2, which includes an absorbent core 21 as illustrated in Figure 3a. Figure 4a shows the absorbent core 21 in a dry state before it absorbs liquid, and Figure 4b shows the absorbent core 21 in a wet state after absorption and swelling.

[0164] The absorbent core 21, comprising an upper core cover layer 24 and a lower core cover layer 25, is shown positioned between the liquid-permeable top sheet 22 and the liquid barrier layer 23. The absorbent core 21 is positioned between the top sheet 22 and the liquid barrier layer 23 with the upper core cover layer 24 facing the liquid top sheet 22 and the lower core cover layer 25 facing the liquid barrier layer 23.

[0165] The top sheet 22 and the liquid barrier layer 23 extend beyond the periphery of the absorbent core 21 and are joined to each other by an edge seal 41 that extends outward along the periphery of the absorbent core 21, along the side edges 26, 27 and end edges 28, 29 of the absorbent core 21. The edge seal 41 between the top sheet 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 width of the absorbent core 21, which is the core width Wc as defined herein. In the example of Figures 3 and 4a, the upper core cover layer 24 and the lower core cover layer 25 have the same width, and therefore the core width Wc.

[0167] The edge seals 41 extend along and directly adjacent to the first and second side edges 26, 27 of the absorbent material, respectively. “Directly adjacent” means that no other seals exist between the first or second edge seal 41 and the first or second side edge of the absorbent material 70. Therefore, the edge seals 41 are seals that limit 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 illustrated transverse section, the sealed width Ws is greater than the core width Wc. Thus, the first and second edge seals 41 extend outward 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 transversely outer portions 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 method of realizing additional space for transverse swelling of the absorbent article can be advantageously combined with the aforementioned method of realizing additional space for swelling in the height direction of the absorbent article. Furthermore, the two proposed methods of realizing additional space for swelling can also be used separately.

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

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

[0171] Generally, absorbent articles 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 top sheet 22. One of the additional lower layers may include a liquid barrier 23. First and second edge seals 41 may be joined 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 joined 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 joined between one of the additional lower layers 23 and the upper core cover layer 24.

[0172] As illustrated in Figures 4a and 4b, the absorbent article may include a top sheet 22 adjacent to the upper core cover layer 24 and a barrier layer 23 adjacent to the lower core cover layer 25. As shown in the example in Figures 4a and 4b, the edge seal 41 can join the top sheet 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 dry state of the article). Thus, the core width Wc (which is the relative width of the upper core cover layer 24 and the lower core cover layer 25) is equal in this case to the width of the upper core cover layer 24. The edge seals 41 are positioned to join the lower core cover layer 25 and the top sheet 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-permeable top sheet 22 may contain or be composed of nonwoven fabric materials. Other suitable top sheet materials include tow fibers, porous foams, plastic films and laminates with apertures, as well as combinations of such materials. The optimal material for the top sheet is soft and non-irritating to the skin, easily penetrated by bodily fluids, and exhibits low rewetting.

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

[0176] The top sheet and / or liquid barrier layer can be further attached to the core cover layer by any method known in the art (e.g., 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, the crotch panel being connected to the front panel along the front panel crotch edge and the crotch panel being connected to the rear panel along the rear panel crotch edge. The front and rear panels may be made from elastic or stretchable web material or elastic laminate material, while the crotch panel may be made from inelastic web material or inelastic laminate material. Alternatively, a pant-type article may have a unitary chassis having an inelastic outer or inner cover web extending over the entire distance between the front panel waist edge and the rear panel waist edge, the cover web constituting the inelastic layers of the front and rear panels respectively, and constituting the crotch web material in the crotch area of ​​the pant-type article.

[0179] The elastically stretchable front body panel and the elastically stretchable rear body panel may include, or be composed of, a stretch-bonded laminated elastic web material.

[0180] A suitable stretch-bonded laminate may include a nonwoven material layer or web (e.g., spunbond nonwovens, airlaid nonwovens, wetlaid nonwovens, carded nonwovens, electrospun nonwovens, or meltblown nonwovens). The nonwoven materials can be bonded by any suitable technique (e.g., by needling, hydroentungling, ultrasonic welding, or thermobonding).

[0181] The fibers of nonwoven materials used herein may be artificial fibers, natural fibers, or mixtures of artificial and natural fibers. Artificial fibers include single-component, two-component, and multi-component polymer fibers (e.g., polyolefins, polyesters, polyacrylates, etc.), as well as regenerated fibers (e.g., viscose fibers and modal fibers, etc.). Natural fibers are, for example, cellulose fibers (e.g., pulp fibers, cotton fibers, flax, hemp, etc.).

[0182] A pant-type article 1 as disclosed herein may have an elastic waist feature 90 positioned along the waist opening 16. The elastic waist feature 90 may be formed by one or more elastic elements extending parallel to the front panel waist edge 7 and the rear panel waist edge 10. One or more elastic waist elements may be incorporated into the front portion 3 and the rear portion 4, or may be applied as separate waistbands attached to the front panel waist edge 7 and the rear panel waist edge 10. The pant-type article 1 shown in the figure has an elastic waist feature 90 extending around the entire circumference of the waist opening 16. However, the elastic waist feature may be positioned along only a portion of the waist opening (for example, along only the rear waist edge, along only the front waist edge, or along a portion of one or both of the front and rear waist edges (the portion having a length shorter than the total length of the corresponding waist edge)).

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

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

[0185] Manufacturing method Suitable manufacturing methods can be used to produce absorbent cores as described herein. For example, absorbent materials can be produced by a method for producing absorbent cores for disposable absorbent sanitary articles as disclosed herein, and such method is - A step of providing a first core cover web having a first surface and a second surface, and advancing the first core cover web in the machine direction, wherein the first core cover web has lateral edges extending in the machine direction, the first core cover width is defined in the machine transverse direction between the lateral edges of the first core cover web, and the machine transverse direction is perpendicular to the machine direction, and - A step of reducing the width of a first core cover web by introducing at least one pleat within the first core cover web, wherein the at least one pleat extends in the machine direction between the side edges of the first core cover web and forms 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, and - A step of applying adhesive to the first surface of the pleated first core cover web, - A step of advancing a pleated first core cover web onto the matting surface of a matting machine, wherein the matting machine has a recess located on the matting surface, the recess having an air-permeable bottom surface, and including at least one channel-forming element, the at least one channel-forming element located on the bottom surface of the recess and protruding from the bottom surface of the recess, - A step of fitting a pleated first core cover web to a recess and at least one channel-forming element on the bottom surface of the recess, wherein a second surface of the first core cover web faces the bottom surface of the recess, causing the pleats in the first core cover web to unfold at least partially on the at least one channel-forming element, - The steps of applying an absorbent material onto the first surface of the first core cover web in the recess, - A step of providing a second core cover web having a first surface and a second surface, - Steps include applying adhesive to the first surface of the second core cover web, - The step of applying a second core cover web to the first core cover web and to an absorbent material placed on top of the first core cover web, - A step of forming an absorbent laminate comprising the absorbent material, the second core cover web, and the first core cover web by pressing the second core cover web together, - The step of forming individual absorbent cores by cutting the absorbent laminate in the transverse direction of the machine, and Includes.

[0186] Referring first to Figure 11, a schematic diagram of a method for producing absorbent cores for use in disposable absorbent sanitary articles is shown.

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

[0188] The first core cover web 104 is passed through a pleating unit 108, in which two pleats 109 are formed in the first core cover web 104, as seen in Figure 14, the pleats 109 extending 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 appropriate number of pleats (e.g., one pleat, three pleats, or more) can be formed in the first core cover web 104 by the pleating unit 108. By pleating the first core cover web 104, the width w of the first core cover web 104 is reduced so that the second width w2 of the pleated first core cover web 104' is smaller 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 machine transverse direction CD perpendicular to the MD, as shown in Figure 14.

[0189] In the next step, an adhesive (e.g., 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 the application of the adhesive, the pleated first core cover web 104' is advanced onto the matting surface 112 on the rotary matting drum 102 of the matting machine 101. The matting drum 102 has a recess 113 located on the matting surface 112 (see Figures 14 and 15), the recess 113 having a bottom surface 114 and including two channeling elements 115. The channeling elements 115 are located on the bottom surface 114 of the recess 113 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 channeling elements on the bottom surface 114 of the recess 113 can be varied as disclosed herein. Therefore, 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 installation of the channel-forming elements 115.

[0190] The pleated first core cover web 104' is then drawn 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 in Figure 15, the pleated first core cover web 104', as seen at the top of the figure, is moved into the recess 113 in the direction of arrow A and adapted to the shape of the recess 113 and the two channel-forming elements 115 within the recess 113, 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 unfolded to cover the bottom 114 of the recess 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 recess 113 by a vacuum force V applied from inside the rotary 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 when 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 excessive stretching or pulling of the first core cover web 104.

[0192] This differs from the prior art application of the first core cover web 104 to a recess 113 having channel-forming elements 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 drawn into the recess 113 by a vacuum force V, causing increased stress within the material at the relatively distinct edges and corners of the channel-forming elements 115. The tension within the first core cover web material can cause tearing or puncture of the first core cover web. 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 non-conforming parts of the first core cover web 104 reduce the available space for filling the recess with absorbent material, as illustrated in Figure 13.

[0193] Next, the absorbent material is applied to the first surface 105 of the first core cover web in a recess 113 on the mat-forming surface 112 of the rotary mat-forming drum 102. In Figure 11, the application of the absorbent material is illustrated by an air-lailing unit 120, in which air-filled wood pulp 121 is mixed with superabsorbent material 122 (e.g., superabsorbent particles or fibers), and the mixture is drawn into the recess 113 covered by the first core cover web 104.

[0194] After the application of the absorbent material, a second core cover web 124 having a first surface 125 and a second surface 126 is supplied, and an adhesive (e.g., 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 to the mat-forming surface 112 of the rotary mat-forming drum 102 by the rotating wheel 131 so as to cover the first core cover web 104 in the recess 113 and the absorbent materials 121, 122 placed on top of the first core cover web 104.

[0195] The first surface 125 of the second core cover web 124 presses together the second core cover web 124 and the first core cover web 104 in a nip 135 between two rollers, thereby forming an absorbent laminate 140 that includes the first surface 105 of the first core cover web 104 and absorbent materials 121, 122 positioned on top of the first core cover web 104, within a recess 113 in the mat-forming surface 112 of the mat-forming drum 102, and 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 brings the core cover webs into direct or substantially direct contact with each other in areas generated in the channel-forming element 115 and generally lacking absorbent material, and in corresponding areas of the second core cover web 124 and the first core cover web 104 located outside the recess 113.

[0196] Alternatively, or in addition to the above, the formation of the absorbent laminate 140 may 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 the absorbent laminate 140 is formed, individual absorbent cores 142 are formed by cutting the absorbent laminate 140 in the transverse direction of the machine in the cutting unit 141.

[0198] Although the methods disclosed herein have been illustrated using a mat forming machine 101 equipped with a rotary mat forming drum 102, it should be understood that the methods disclosed herein are equally applicable to mat forming on a mobile conveyor.

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

[0200] As disclosed herein, each channel-forming element 115 in a continuous recess can be composed of multiple element parts, which are distributed equidistantly around the periphery 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 periphery of the mat-forming drum 102. When the absorbent laminate 140 is cut to form individual absorbent cores 142, the absorbent laminate 140 is cut between the element parts in the machine transverse direction CD. Thus, the number of channel-forming element parts in each channel-forming element 115 corresponds to the number of cores formed on the mat-forming drum during one rotation.

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

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

[0203] Further details regarding the manufacturing method described above can be found in the concurrently pending Patent Document 2.

[0204] This disclosure is subject to modification within the scope of the attached claims. For example, materials and dimensions are subject to modification.

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

[0206] Test method for measuring seal strength At least 10 days must pass between the manufacturing of the item and the opportunity to measure the seal strength.

[0207] The core, with its 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 seal strength tests.

[0208] An exposed core with a core cover layer is placed flat on the support surface. If elastic material is present within the core, the core should be stretched and secured in the appropriate position on the support surface using strips of tape, mechanical fasteners, or similar means.

[0209] Rectangular samples (25 mm wide) are punched out from the core, with each sample containing a portion of the seal to be tested. The samples are punched out with the width direction of each sample parallel to the longitudinal centerline of the core, and the length direction 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, with the inner edge portions of the upper and lower core cover layers forming cover flaps extending 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 testing machine clamp. It is important that the longitudinal edges of the test specimen are uniform and free from fracture notches.

[0210] The samples are punched out immediately adjacent to each other. For example, eight 25mm wide test samples can be punched out from a seal that is 210mm long, in which case 10mm of the seal remains at one end and is not used for testing.

[0211] The samples (prepared as described above) are conditioned for 24 hours in a controlled environment with a temperature set to 23°C ± 1°C and a relative humidity of 50% ± 5%. The tests are conducted in this same environment.

[0212] The samples are tested using conventional tensile testing machines (for example, those available from Lloyd Instruments or Instron Corporation).

[0213] The core cover flap is inserted vertically into the clamp of the tensile testing machine. The clamp should be at least as wide as the sample. During insertion, tension on the seal should be avoided, but excessive slack in the sample being tested should also be avoided. 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 test specimen is mounted in the clamp of the testing instrument.

[0214] The seal strength of the seal being tested is an arithmetic mean based on all individual samples that can be cut along the part of the seal to be inspected. For example, the strength of the entire 210 mm long seal as described above is the average seal strength obtained from testing eight test pieces 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 that measures 5x5cm (however, smaller feet can be used for smaller areas of interest). The foot should be lowered gently onto the material, and the thickness value is read after 5 seconds.

[0217] Measurement of width and length It should be noted that, as used in this application, the terms “length” and “width” refer to the maximum longitudinal dimension and the maximum transverse dimension, respectively, when viewed on the absorbent core or article in a dry, unused state, unless otherwise specified. Prior to dimensional measurement, any elastic components are neutralized (for example, by cutting them at regular intervals) and the object is placed flat against a planar surface. Measurements of the core are taken after removal from any surrounding elastic chassis.

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

[0219] The core, with its surrounding core cover layers 24 and 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 width measurements are taken.

[0220] An exposed core with a core cover layer is placed flat on the support surface. If elastic material is present within the core, the core should be stretched and secured in the appropriate position on the support surface using strips of tape, mechanical fasteners, or similar means.

[0221] Rectangular samples (10 mm wide) are punched out from the core immediately adjacent to one another, and therefore each sample corresponds to a transverse segment in a hypothetical set of adjacent transverse segments S1 to S9 of the absorbent core 21, as described above in relation to Figure 2.

[0222] The samples are punched out such that the width direction of each sample is parallel to the longitudinal centerline of the core, and the length direction of each sample is perpendicular to the longitudinal centerline of the core.

[0223] As described above, the samples are punched out immediately adjacent to each other. For example, from an absorbent core with a pair of channels having a channel seal with a longitudinal channel seal length of 215 mm, 21 test samples with a width of 10 mm can be punched out, in which case 5 mm of the channel seal remains at one end and is not used for testing.

[0224] The samples (prepared as described above) are conditioned for 24 hours in a controlled environment with a temperature set to 23°C ± 1°C and a relative humidity of 50% ± 5%. The tests are conducted in this same environment.

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

[0226] The "tube" is cut open by cutting the upper core cover 24 between channel seals 37 and 38 along a line substantially parallel to the width direction of the sample (i.e., substantially parallel to the longitudinal axis L of the core). The absorbent material 70 is slowly removed from the cut-open tube. Additionally, material perpendicular to seal 37 can be removed for the purpose of determining the width of the core cover layers 24, 25 between channel seals 37 and 38 in the unfolded state.

[0227] The tube is unfolded slowly. Thus, the unfolded tube, as seen in the longitudinal direction of the sample (the 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 terminates with a second cut edge 82.

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

[0229] The tube material is unfolded, suspended perpendicular to the longitudinal dimension of the sample, and measurements are taken.

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

[0231] A 10g weight is attached to the second cut edge 82 of the tube material, stretching the sample material in the longitudinal direction of the sample, so that the force from the weight is evenly distributed across the width of the sample. Thus, the sample material is suspended with its longitudinal direction parallel to the vertical.

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

[0233] The width W1 of the upper core cover material between channel seal 37 and 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 longitudinal direction of the sample. Measurements are taken along the centerline of the sample.

[0234] Therefore, the widths W1 and W2 between channel seals 37 and 38 in the sample are measured in the same transverse section with respect to the first core cover layer and the second core cover layer.

[0235] From the measurements of the first and second widths W1 and W2 in each sample (corresponding to a hypothetical segment of the absorbent core), it is possible to calculate the relationship between the first and second widths in the corresponding transverse segment. Therefore, measurements taken along the centerline of the sample are considered representative of the corresponding transverse segment.

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

[0237] In other variations, one of the first and second widths W1 and W2 can have different values ​​in different hypothetical segments along the channel seal length. This can be, for example, in some variations where the channel containing the channel seal 37 is linear but inclined with respect to the longitudinal direction L, or in some variations where the channel with the channel seal is curved.

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

[0239] 1. Pants-type item 3 Front part 4 Rear part 6. Crotch area 7 Front waist edge 8. First front side edge 9. Second front lateral 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 Absorbent Assembly 21 Absorbent core 22 Top Sheets 23. Liquid barrier layer, additional lower layer 24 Upper core cover layer 24c Upper Core Cover 24c' First part of the upper core cover 24 24c” Second part of the upper core cover 24 25 Lower core cover layer 25c Lower core cover 26 First lateral edge 27 Second lateral edge 28 First end edge 29 Second end edge 33 First lateral region 34 Second lateral region 35. The 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. Forward transition zone, first transition zone 55. Rearward transition zone, second transition zone 70 Absorbent materials 71 First lateral edge 72 Second lateral edge 81 First cut edge 82 Second cut edge 90 Elastic waist feature 101 Mat Forming Machine 102 Rotary mat forming drum 104 The First Core Cover Web 104' First Core Cover Web 105 First surface 106 Second surface 108 Pleated Unit 109 Pleats 110 First adhesive applicator 111 Side edge 112 Matte-formed surface 113 Recess 114 Bottom surface 115 Channel-forming element 120 Air Aeration Unit 121 Wood pulp 122 Superabsorbent Materials 124 The Second Core Cover Web 125 First surface 126 Second surface 130 Second adhesive applicator 131 Rotating Wheels 140 Absorbent Laminate 141 Cutting Unit 142 Absorbent core CD machine cross direction H thickness direction L Longitudinal direction Lc Longitudinal centerline MD machine direction S1-S9 Adjacent transverse segments T transverse direction V vacuum force W1 First width W1' Vertical length between the first cut edge 81 and the first channel seal 37 W1” Vertical length between the second channel seal 38 and the second cut edge 82 W2 Second width W3 Third width Wa absorbent material width Wc core width Ws sealed width

Claims

1. An absorbent core (21) having a length in the longitudinal direction (L) and a width in the transverse direction (T), wherein the transverse direction (T) is perpendicular to the 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), The channel (35) has no absorbent material or substantially no absorbent material and has a first channel seal (37) extending therein. The channel (36) has no absorbent material or substantially no absorbent material and has a second channel seal (38) extending therein. The first channel seal (37) and the second channel seal (38) join the upper and lower core cover layers (24, 25) within the channels (35, 36) and extend along the longitudinal channel seal length (Ls). The absorbent core is divided along the channel seal length (Ls) into a virtual set of one or more adjacent transverse segments (S1 to S9), Each transverse segment has a segment length of 10 mm and includes the first channel seal (37) and the second channel seal (38). The set includes the maximum possible number of adjacent transverse segments (S1 to S9) along the channel seal length (Ls), The absorbent core (21) has respect to at least one transverse segment of the set of segments, The lower core cover layer (25) and the upper core cover layer (24) have a first width (W1) between the first channel seal (37) and the second 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 first channel seal (37) and the second channel seal (38), and the first and second widths (W1, W2) of the upper and lower core cover layers (24, 25) are the widths of the upper and lower core cover layers (24, 25) between the first channel seal (37) and the second channel seal (38) in an unfolded and completely flat state, and the first width (W1) is 120% or more of the second width (W2). 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 in a first side seal in a first side region (33) extending along a first side edge (26) of the absorbent material (70), and / or in a second side seal in a second side region (34) extending along a second side edge (27) of the absorbent material (70), and the sealing strength of the first channel seal (37) and the second channel seal (38) of the absorbent core (21) is higher than the sealing strength of the first and / or second side seals (33, 34) of the absorbent core (21), or Absorbent core (21) wherein in at least a portion of the absorbent core (21), the upper core cover layer (24) and the lower core cover layer (23) are not sealed to each other in the portion of the absorbent core (21) that extends transversely beyond the first channel seal (37) to the first side edge (71) of the absorbent core (21), and / or in the portion of the absorbent core (21) that extends transversely beyond the second channel seal (38) to the second side edge (72) of the absorbent core (21).

2. The absorbent core according to claim 1, wherein in at least one transverse segment, the first width (W1) is 130% or more of the second width (W2).

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

4. The absorbent core according to claim 1, wherein at least a portion of the absorbent core (21) includes at least one transverse segment.

5. The absorbent core according to claim 1, wherein the sealing strength of the first channel seal (37) and the second channel seal (38) is 2.5 N / 25 mm or more, and / or the sealing strength of the first and second side seals (33, 34) is 2.0 N / 25 mm or less.

6. The absorbent core according to claim 1, wherein in at least one transverse segment, the first width (W1) is 135% or more of the second width (W2).

7. An absorbent article (1) comprising the absorbent core (21) described in claim 1.

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

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

10. The absorbent article includes one or more additional upper layers (22) above the upper core cover layer (24), one or more additional lower layers (23) below the lower core cover layer (25), and / or The absorbent article according to claim 9, 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).

11. The absorbent article according to claim 10, wherein one of the additional upper layers comprises a liquid-permeable top sheet (2).

12. The absorbent article according to claim 10, wherein one of the additional lower layers comprises a liquid barrier layer (23).

13. The absorbent article according to claim 9, wherein the first and second edge seals (41) and the first channel seal (37) and the second channel seal (38) are adhesive seals, welded seals, or a combination of adhesive seals and welded seals.

14. The absorbent article according to claim 13, wherein the first edge seal (41), the second edge seal (41), and the respective first channel seal (37) and second channel seal (38) are adhesive seals.

15. The absorbent core according to claim 1, wherein in at least one of the segments, the third width (W3) measured between the first channel seal (37) and the second channel seal (38) of the absorbent core (21) is between 20 mm and 60 mm.

16. The absorbent core according to claim 15, wherein in at least one of the segments, the absorbent material (70) has an absorbent width (Wa), the upper core cover layer (24) and the lower core cover layer (25) extend over a mutual width that is the core width (Wc), and the absorbent width (Wa) is less than or equal to the core width (Wc).

17. The absorbent core according to claim 16, wherein the absorbent material width (Wa) is 90% or more of the core width (Wc).

18. The absorbent core according to claim 16, wherein the third width (W3) is in the range of 15% to 40% of the absorbent material width (Wa).

19. The absorbent core according to claim 1, wherein the pair of channels (35, 36) are linear and extend parallel to the longitudinal direction.

20. The absorbent core according to claim 1, 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 first channel seal (37) and the second channel seal (38) is in the range of 50 mm to 500 mm.

21. The absorbent core according to claim 1, wherein the upper and lower core cover layers (24, 25) are made of a nonwoven fabric material.

22. The absorbent core according to claim 1, wherein the absorbent material (70) comprises cellulose pulp fibers and a superabsorbent material, or is composed of cellulose pulp fibers and a superabsorbent material.

23. The absorbent core according to claim 22, wherein the superabsorbent material is present in the absorbent material (70) in an amount of 5% to 80% by weight of the absorbent material (70).

24. The absorbent core according to claim 1, wherein the absorbent material between the first channel seal (37) and the second channel seal (38) has a basis weight in the range of 500 gsm to 1200 gsm.

25. The absorbent core according to claim 1, wherein the upper and lower core cover layers (24, 25) are formed from a single continuous cover material wrapped around the absorbent material (70).

26. The absorbent core according to claim 1, wherein the upper core cover layer (24) and the lower core cover layer (25) are separate core cover layers.

27. The absorbent core according to claim 1, wherein the absorbent material (70) has an hourglass shape or a T shape in a plane defined by the longitudinal direction (L) and the transverse direction (T).

28. The absorbent core according to claim 1, wherein the absorbent material (70) has a rectangular shape comprising side edges (26, 27) extending in the longitudinal direction (L) and end edges (28, 29) extending in the transverse direction.

29. The absorbent core according to claim 1, wherein the absorbent core (21) includes a central part (51), the central part (51) being positioned between a first end part (52) and a second end part of the absorbent core (21) when viewed in the longitudinal direction (L), and the pair of channels (35, 36) being at least partially positioned within the central part (51) of the absorbent core (21).

30. The absorbent core according to claim 29, wherein the central part (51) has a thickness greater than the thickness of the first end part (52) and a thickness greater than the thickness of the second end part (53).

31. The absorbent core according to claim 30, wherein the central part (51) of the absorbent core (21) has a uniform thickness, each of the first end part (52) and the second end part (53) of the absorbent core (21) has a uniform thickness, and 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).

32. The absorbent core according to claim 31, 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, 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.

33. The absorbent core according to claim 31, 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.

34. The absorbent core according to claim 31, 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.

35. The absorbent core according to claim 31, wherein at least two of the absorbent core (21), the central part, the first end part, and the second end parts (51, 52, 53), have different absorption capacities.

36. The absorbent core according to claim 1, wherein the absorbent core has a length determined by the distance between the first end edge (28) at a point on the first end edge (28) where it intersects the longitudinal centerline (Lc) and the second end edge (29) at a point on the second end edge (29) where it intersects the longitudinal centerline (Lc), and the length of the absorbent core (21) is in the range of 300 mm to 700 mm.

37. The absorbent core according to claim 1, wherein at least one of the transverse segments of the absorbent core comprises at least one-quarter of the segments in the set of segments.

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