Methods for packaging absorbent materials

Abstract

The absorbent article has a front waist region, a rear waist region, and an intermediate region disposed between the front waist region and the rear waist region. The absorbent article includes a topsheet, a backsheet, an absorbent core structure disposed between the topsheet and the backsheet, and a flexible bonded channel region formed in at least the intermediate region. The absorbent core structure includes an upper nonwoven layer having polymer fibers, a lower nonwoven layer having polymer fibers, and an inner core layer disposed between the upper nonwoven layer and the lower nonwoven layer. The flexible bonded channel region has a dry channel depth of at least 1.0 mm and a channel width of about 1.0 mm to about 3.0 mm. The flexible bonded channel region has a CD bending resistance index of about 1.1 to about 3.0, and a dry MD bending resistance of less than about 0.04 N / mm.

Description

[Technical Field]

[0001] This disclosure relates to an absorbent article having a flexible binding channel region. More specifically, to an absorbent article having a flexible binding channel region that remains flexible while closely conforming to the body. [Background technology]

[0002] Absorbent articles, such as diapers, training pants, women's pads, and adult incontinence pads, are widely used among consumers. Generally, these absorbent articles include a top sheet and a back sheet, with an absorbent core structure positioned between them. These absorbent articles are designed to absorb and retain fluids and other excretions from the human body to prevent soiling of the body and clothing.

[0003] To effectively absorb bodily fluids without leakage, absorbent articles must conform closely to the wearer's body so that they can capture fluids at their intended location (e.g., the center of the absorbent core structure). Historically, in menstrual applications, channels formed by embossing have been utilized to create flex lines in thicker and / or stiffer products to provide a specific pad shape during use and help improve body fit. In conventional cellulose-based absorbent core structures, channels are formed by applying high compressive force to densify the cellulose to a point where it is irreversibly compressed. While such channels can provide preferred flex locations within the absorbent article, the high compressive force (i.e., densification) required to form (and keep the channels in place) creates rigidity that can hinder the absorbent article's ability to conform to the wearer's body in both the longitudinal and transverse directions. Therefore, these products are not considered to conform or fit as closely as possible to the wearer's body, particularly in areas adjacent to the area of ​​fluid discharge during use, and thus leakage can occur. To effectively conform to the body, it is desirable that absorbent materials bend at preferred locations in both the longitudinal and transverse directions. [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] There is a need for an absorbent article that includes channels but is still conformable to the body and can be flexible in both the longitudinal and transverse directions. [Means for solving the problem]

[0005] This disclosure provides an absorbent core structure in which a liquid absorbent material can be sandwiched between two nonwoven layers that can be plastically deformed to form a flexible bonded channel region, without densifying the absorbent core structure and / or inner core layer, in order to solve the problem of rigid, poorly conforming absorbent articles having channels. As described herein, the flexible bonded channel region may be flexible in both the longitudinal and transverse directions, so that the absorbent article can conform closely to the body.

[0006] The absorbent article comprises a front end region, a rear end region, and an intermediate region disposed between the front end region and the rear end region; a top sheet; a back sheet; and an absorbent core structure disposed between the top sheet and the back sheet, the absorbent core structure comprising (a) an upper nonwoven fabric layer containing polymer fibers, (b) a lower nonwoven fabric layer containing polymer fibers, and (c) an inner core layer disposed between the upper nonwoven fabric layer and the lower nonwoven fabric layer, containing cellulose fibers and superabsorbent particles; and a flexible bonded channel region formed in at least the intermediate region, having a dry channel depth of at least 1.0 mm and a width of about 1.0 mm to about 3.0 mm, a CD stiffness index of about 1.1 to about 3.0, and a dry MD stiffness of less than about 0.04 N / mm when measured according to the flexible bonded channel MD stiffness method.

[0007] The disposable absorbent article comprises a top sheet; a back sheet; and an absorbent core disposed between the top sheet and the back sheet, wherein the top sheet forms the surface facing the wearer of the absorbent article, and the back sheet forms the surface facing the outside of the absorbent article, and the absorbent core structure comprises (a) an upper nonwoven fabric layer containing polymer fibers, (b) a lower nonwoven fabric layer containing polymer fibers, and (c) an inner core layer disposed between the upper nonwoven fabric layer and the lower nonwoven fabric layer, wherein the inner core layer contains cellulose fibers and superabsorbent particles, and the inner core layer contains cellulose fibers of about 125 gsm to about 400 gsm, and the surface facing the wearer of the absorbent article has a dry MD stiffness of less than about 0.04 N / mm and about 0.05 g / cm² when measured according to the flexible bond channel MD stiffness method. 3 ~about 0.3g / cm 3 It comprises a flexible binding channel region having a density of .

[0008] The disposable absorbent article comprises a top sheet; a back sheet; and an absorbent core structure disposed between the top sheet and the back sheet, comprising an upper nonwoven fabric layer containing polymer fibers and an inner core layer containing cellulose fibers of about 125 gsm to about 400 gsm, wherein the inner core layer has a surface facing the wearer and a surface facing the outside, and the upper nonwoven fabric layer is in direct contact with the wearer-facing surface of the inner core layer; and a flexible bond channel region comprising one or more flexible bond embossings having an embossing length of about 1.0 mm to about 4.0 mm, having a channel depth of at least 1.0 mm and a width of about 1.0 mm to about 3.0 mm, and having a dry MD stiffness of less than about 0.04 N / mm when measured according to the flexible bond channel MD stiffness method. [Brief explanation of the drawing]

[0009] [Figure 1] This is a diagram of the absorbent core structure according to this disclosure. [Figure 2A] This is a diagram of an absorbent article according to this disclosure. [Figure 2B] This is another diagram of the absorbent article according to this disclosure. [Figure 3] This is a cross-sectional view of the absorbent core structure. [Figure 4] This is an enlarged view of the structural connection site as disclosed herein. [Figure 5] Figure 4 is a cross-sectional view of the structural connection site. [Figure 6] This is a cross-sectional view of the absorbent article according to this disclosure. [Figure 7A] This is a top view of an absorbent article having a flexible binding channel region according to the present disclosure. [Figure 7B] This is another top view of an absorbent article having a flexible binding channel region according to the present disclosure. [Figure 8] This is an enlarged top view of the surface of an absorbent article containing a flexible bonding channel region. [Figure 9] This is a perspective view of the flexible binding channel region within an absorbent article as disclosed herein. [Figure 10A] This is a partial cross-sectional view along line 10-10 in Figure 7A of an absorbent article containing a flexible binding channel region, according to various non-limiting configurations of the present disclosure. [Figure 10B] This is a partial cross-sectional view along line 10-10 in Figure 7A of an absorbent article containing a flexible binding channel region, according to various non-limiting configurations of the present disclosure. [Figure 11A] This is a diagram of the test method configuration for the wet and dry CD ultra-high sensitivity three-point bending method. [Figure 11B] This is a diagram of the test method configuration for the wet and dry CD ultra-high sensitivity three-point bending method. [Figure 11C] This is a diagram of the test method configuration for the wet and dry CD ultra-high sensitivity three-point bending method. [Figure 12] This is a diagram illustrating the test method configuration for wet and dry cluster compression tests. [Figure 13A] This is a diagram illustrating the test method configuration for wet and dry cluster compression tests. [Figure 13B] This is a diagram illustrating the test method configuration for wet and dry cluster compression tests. [Figure 14A]These are illustrative graphs of cluster curves obtained from wet and dry cluster compression tests. The graphs in Figures 14A and 14B are shown to illustrate how calculations in the method may be performed and do not represent the data described herein. [Figure 14B] These are illustrative graphs of cluster curves obtained from wet and dry cluster compression tests. The graphs in Figures 14A and 14B are shown to illustrate how calculations in the method may be performed and do not represent the data described herein. [Figure 15] This is an exemplary graph of the channel depth and width of a flexible-connected channel region relative to a channel-free region, obtained from the flexible-connected channel depth and width method. The graph in Figure 15 is shown to illustrate how the calculations in the method may be performed and does not represent the data described herein. [Modes for carrying out the invention]

[0010] When used in this specification, “disposable absorbent articles” or “absorbent articles” refer to articles intended for disposal after use, such as diapers, training pants, diaper pants, re-fastening pants, adult incontinence pads, adult incontinence pants, women’s hygiene pads, and cleaning pads.

[0011] When used herein, "absorbent core structure" shall be used in relation to the upper nonwoven fabric layer, the lower nonwoven fabric layer, and the inner core layer disposed between the upper and lower nonwoven fabric layers.

[0012] As used herein, “hydrophilic” and “hydrophobic” have well-established meanings in the art with respect to the water contact angle on the surface of a material. Therefore, a material with a water contact angle greater than about 90 degrees is considered hydrophobic, and a material with a water contact angle less than about 90 degrees is considered hydrophilic. A hydrophobic composition increases the water contact angle on the surface of a material, while a hydrophilic composition decreases it. Notwithstanding the foregoing, references to relative hydrophobicity or hydrophilicity between a material and a composition, between two materials, and / or between two compositions do not imply that the material or composition is hydrophobic or hydrophilic. For example, a composition may be more hydrophobic than a material. In this case, neither the composition nor the material may be hydrophobic. However, the contact angle exhibited by the composition is greater than that of the material. As another example, a composition may be more hydrophilic than a material. In this case, neither the composition nor the material may be hydrophilic. However, the contact angle exhibited by the composition is smaller than that of the material.

[0013] As used herein, “machine direction” refers to the direction in which the web flows through the absorbent material processing process. For brevity, it may be referred to as “MD.”

[0014] In this specification, "machine transverse direction" refers to the direction perpendicular to the MD. For brevity, it may be referred to as "CD".

[0015] As used herein, “elastic” refers to a material that tends to retain its shape in both dry and wet conditions, and, when subjected to a compressive force, tends to recover its original pre-compression shape when such force is removed. In some embodiments, the upper and / or lower nonwoven layers described herein may be elastic.

[0016] As used herein, “facing the wearer” (which may also be referred to as “facing the body”) and “facing the outside” (which may also be referred to as “facing the garment”) refer to the relative position of an element or the surface of an element or group of elements, respectively. “Facing the wearer” means that the element or surface is closer to the wearer while being worn than any other element or surface. “Facing the outside” means that the element or surface is further away from the wearer while being worn than any other element or surface (i.e., the element or surface is closer to the wearer’s garment that may be worn over an absorbent article).

[0017] With respect to a first feature of an article and its position relative to a second feature or location on the article, “inside” means that the first feature is located closer to each axis of the article than the second feature or location, along the horizontal xy plane generally occupied by the article, when it is unfolded flat on a horizontal surface, subject to any shrinkage induced by any pre-tensioned elastomer material included, and stretched to its full longitudinal and transverse dimensions along the web material of its constituent parts. Transversely inside means that the first feature is closer to the longitudinal axis, and longitudinal inside means that the first feature is closer to the transverse axis. Conversely, with respect to a first feature of an article and its position relative to a second feature or location on the article, “outside” means that the first feature is further from each axis of the article than the second feature or location.

[0018] It should be understood that all maximum numerical limits given throughout this specification include all lower numerical limits as if they were explicitly stated herein. All minimum numerical limits given throughout this specification include all higher numerical limits as if they were explicitly stated herein. All numerical ranges given throughout this specification include all narrow numerical ranges that fall within such broad numerical ranges as if they were explicitly stated herein.

[0019] The disposable absorbent articles described herein may comprise a top sheet, a back sheet, and an absorbent core structure disposed between them. The absorbent core structure may comprise an upper nonwoven layer and a lower nonwoven layer, with an inner core layer disposed between the upper and lower nonwoven layers. The inner core layer may be housed within the nonwoven layers by substantially sealing at least the left and right regions of the upper and lower nonwoven layers in a periphery seal. In some configurations, the upper and lower nonwoven layers may be joined by a periphery seal extending around the entire periphery of the inner core layer. The absorbent article may further comprise one or more flexible bond channel regions, including adjacently positioned flexible bond embossings.

[0020] As used herein, “flexible bonded channel region” refers to a generally elongated recess formed in at least a portion of an absorbent article and extending partially or completely through the z-thickness of the absorbent article. The flexible bonded channel region can reduce the thickness of the absorbent article in the z-direction and can act as a preferred bending line in the absorbent article, allowing the article to bend in a particular direction to fit more closely to the wearer’s body. The flexible bonded channel region may also act as a fluid wicking or fluid transport barrier, which can reduce the possibility of fluid moving around the absorbent article and causing leakage.

[0021] In some embodiments, a disposable absorbent article may have a structure comprising (in order from the surface facing the wearer to the surface facing outward) a top sheet, an upper nonwoven layer, an inner core layer, a lower nonwoven layer, and a back sheet. In some embodiments, the top sheet may be in direct contact with the upper nonwoven layer, the upper nonwoven layer may be in direct contact with the inner core layer, and / or the inner core layer may be in direct contact with the lower nonwoven layer. "Direct contact" means that there are no further intermediate constituent layers between each of the layers that are in direct contact. However, it is not excluded that an adhesive material may be disposed between at least a portion of the above-mentioned layers.

[0022] Referring to Figures 1 and 3, the absorbent core structure 10 may include an upper nonwoven fabric layer 210 and a lower nonwoven fabric layer 220 (collectively referred to herein as the upper nonwoven fabric layer and the lower nonwoven fabric layer or the upper nonwoven fabric and the lower nonwoven fabric), and an inner core layer 200 disposed between the upper nonwoven fabric layer 210 and the lower nonwoven fabric layer 220. The absorbent core structure 10 may include an inner core layer 200 containing a liquid absorbent material. Although not limited by theory, the absorbent core structure is thought to be able to recover its shape in a dry or wet state over a range of body movement and compression. The liquid absorbent material may include a matrix (sometimes referred to herein as "fluff / AGM") containing cellulose fibers and superabsorbent particles. The upper nonwoven fabric layer 210 and the lower nonwoven fabric layer 220 may be joined to each other in the periphery seal 230 using adhesives or other conventional bonding methods, including but not limited to ultrasonic bonding, melt bonding, crimping, and combinations thereof.

[0023] The upper nonwoven fabric layer 210 and the lower nonwoven fabric layer 220 may extend outward from the periphery of the inner core layer, or they may be joined together to form a periphery seal 230. In some configurations, the entire inner core layer 200 may be located inside the periphery seal 230. The periphery seal 230 can help seal the absorbent material of the inner core layer 200 to the inside of the upper nonwoven fabric layer 210 and the lower nonwoven fabric layer 220. In some configurations, the periphery seal 230 may extend around the entire periphery 200a of the inner core layer. In some configurations, the periphery seal 230 may extend partially around the periphery of the inner core layer.

[0024] In some configurations, the upper nonwoven layer 210 and the lower nonwoven layer 220 may be separate materials that can be cut to approximately the size and shape of the inner core layer 200 to fit between the top sheet and the back sheet, but the upper nonwoven layer 210 and the lower nonwoven layer 220 may not substantially extend to either the front or rear end region of the absorbent article. In some configurations, the upper nonwoven layer 210 and / or the lower nonwoven layer 220 may extend from the front end region of the absorbent article to the rear end region of the absorbent article.

[0025] The flexibility and / or elasticity of the absorbent core structure results in an absorbent article that comfortably conforms to the wearer's anatomical shape while efficiently managing fluid as it leaves the body. Unexpectedly, this can be achieved without typical high-density rigidity (for wet integrity) by utilizing elastic upper and lower nonwoven fabric layers composed of elastic polymers located above and below the loosely filled fluff / AGM matrix of the inner core layer. This absorbent core structure can load structural loads and recover its shape when wet without physically rigidifying or losing desired structural properties.

[0026] When the selected elastic upper nonwoven fabric 210 and elastic lower nonwoven fabric 220 are positioned above and below the fluff / AGM matrix of the inner core layer and specially bonded to and around the fluff / AGM matrix, wet coherence / shape stability in the cellulose-rich absorbent core structure is expected to occur without substantial densification and rigidity. The upper and lower nonwoven fabrics require sufficient resilience after compression to return the fluff / AGM matrix to its original state or a stable fiber orientation. Wrapping or encapsulating a cellulose-rich fluff core with simple cellulose tissue or a nonwoven material with low elasticity may result in insufficient resilience energy to restore shape during use, especially when wet. The structural wet elastic nonwoven fabrics detailed herein may exhibit post-compression resilience energy sufficient to restore the cellulose-rich fiber matrix and selected to provide high compression recovery with relatively low stiffness in both dry and wet conditions.

[0027] Furthermore, it has been found that it is possible to fabricate absorbent articles containing flexible binding channel regions while maintaining the flexibility of the absorbent article in both the transverse and longitudinal directions, enabling the absorbent article to better conform to the body. Although not limited by theory, it is thought that the upper nonwoven fabric can plastically deform and maintain the channel structure without the need to permanently compress (densify) the fluff / AGM of the inner core layer.

[0028] A suitable upper nonwoven fabric layer may have a basis weight of approximately 30 gms to approximately 85 gms, or approximately 35 gms to approximately 70 gsm, or approximately 40 gms to approximately 60 gsm. The upper nonwoven fabric layer may have a tensile stiffness of approximately 0.3 N / mm to approximately 1.6 N / mm. The upper nonwoven fabric layer may have a breaking strain of more than approximately 10%, or approximately 10% to approximately 50%, or approximately 20% to approximately 40%. The upper nonwoven fabric layer may have a permanent strain of approximately 0.005 to approximately 0.013 mm / mm, or 0.005 to approximately 0.0090 mm / mm.

[0029] A suitable lower nonwoven fabric layer may have a basis weight of approximately 10 to approximately 40 gsm, or approximately 15 to approximately 20 gsm. The lower nonwoven fabric layer may have a tensile stiffness of approximately 0.2 N / mm to approximately 1.6 N / mm. The lower nonwoven fabric layer may have a breaking strain of more than approximately 10%, or approximately 10% to approximately 50%, or approximately 20% to approximately 40%. The lower nonwoven fabric layer may have a permanent strain of approximately 0.005 to approximately 0.013 mm / mm.

[0030] The upper and lower nonwoven fabric layers may contain polymer fibers. Suitable upper and lower nonwoven fabric fibers may be selected from PET (polyethylene terephthalate), PP (polypropylene), BiCo (two-component fiber) selected from PE / PP (PE sheath and PP core) and / or PE / PET (PE sheath and PET core), PLA (polylactic acid), and combinations thereof.

[0031] A suitable upper nonwoven fabric layer may contain approximately 60-100%, or approximately 70-100%, of synthetic fibers and approximately 0-40%, or approximately 0-30%, of regenerated cellulose fibers (such as rayon and / or viscose).

[0032] The upper nonwoven fabric layer may contain fibers having a staple length of approximately 10 mm or more than approximately 25 mm, or approximately 10 mm to approximately 100 mm, approximately 20 mm to approximately 75 mm, or approximately 25 mm to approximately 50 mm. The upper nonwoven fabric layer may contain fibers having a fiber diameter of approximately 1.3 DTex to approximately 10 DTex, approximately 1.3 DTex to approximately 6.0 DTex, or approximately 2.0 DTex to approximately 5.0 DTex. In some configurations, the upper nonwoven fabric layer may contain fibers, which are a blend of staple fibers having a fiber diameter of approximately 2.0 DTex to approximately 10 DTex.

[0033] The lower nonwoven layer may contain fibers having lengths of approximately 10 mm or 25 mm, or approximately 10 mm to 100 mm, approximately 20 mm to 75 mm, or approximately 25 mm to 50 mm. In some configurations, the lower nonwoven layer may contain continuous fibers. The lower nonwoven layer may contain fibers having fiber diameters of approximately 1.3 DTex to 5.0 DTex, approximately 1.3 DTex to 3.3 DTex, approximately 1.3 DTex to 2.2 DTex, or approximately 2.0 DTex to 10 DTex. In some configurations, the lower nonwoven layer may contain fibers, which are a blend of fibers having fiber diameters of approximately 0.1 DTex to 6.0 DTex.

[0034] In some configurations, a suitable fiber combination may include upper nonwoven polymer fibers having a diameter of about 2.0 DTex to about 10 DTex and lower nonwoven polymer fibers having a diameter of about 1.7 DTex to about 5 DTex. In some configurations, a suitable fiber combination may include upper nonwoven polymer fibers having a diameter of about 1.3 DTex to about 2.2 DTex and lower nonwoven polymer fibers having a diameter of about 1.7 DTex to about 5 DTex.

[0035] Nonwoven layers containing polymer fibers can retain their shape when wet and resist plasticization, but the nonwoven layers containing polymer fibers are attached to the fluff / AGM matrix either directly to the fluff / AGM matrix or through the application of a core structure adhesive applied to either the fluff / AGM matrix or the elastic nonwoven layer, and the application of the core structure adhesive is carried out via a conventional spray coating method, the method being selected so as not to obstruct the fluid flow to the fluff / AGM matrix while achieving bonding. In addition, the upper and lower nonwoven layers may have at least a partial periphery seal to better connect the upper and lower nonwoven layers to the inner core layer contained within the upper and lower nonwoven layers. This periphery seal typically includes at least an intermediate area of ​​the absorbent article in the region located between the wearer's inner thighs. The presence of a periphery seal on the outside of the fluff / AGM matrix helps ensure that the upper and lower nonwoven layers maintain their structural function without separating during physical deformation when the upper and lower nonwoven layers are bonded by conventional means (e.g., adhesives, polymer welding, and / or strong physical entanglement), thus helping to limit any potential issues related to integrity and agglomeration. Forming a periphery seal that substantially accommodates the inner core layer may allow for the removal of any excess material and enable the absorbent core structure to be molded to conform to the inner thigh shape.

[0036] Suitable upper and lower nonwoven fabric layer materials can bend and return to their original shape in response to bending forces. Thin or highly flexible materials bend easily with low peak forces (loads) and low bending energy. Unsuitable materials that bend easily do not have sufficient recovery energy and, therefore, remain deformed and bent due to insufficient recovery energy. Suitable materials have sufficient energy to recover to their initial state before bending. Materials with sufficient bending recovery energy can be considered elastic upper and lower nonwoven fabric layers.

[0037] As described above, the upper and lower nonwoven fabrics may contain polymer fibers. Polymer fibers may be included to help provide structural integrity to the upper and lower nonwoven fabrics. Polymer fibers can help increase the structural integrity of the upper and lower nonwoven fabrics in both the machine direction (MD) and the machine transverse direction (CD), thereby facilitating web handling during processing of the upper and lower nonwoven fabrics for incorporation into the pad.

[0038] Polymer fibers of any suitable composition can be selected. Some examples of suitable polymer fibers include two-component fibers containing polyethylene (PE) and polyethylene terephthalate (PET) components or polyethylene terephthalate and copolyethylene terephthalate components. The components of the two-component fiber may be arranged in a sheath-core configuration, a parallel configuration, an eccentric sheath-core configuration, a trefoil configuration, or other suitable configurations. In some configurations, the polymer fiber may include two-component fibers having a PE / PET component arranged in a concentric sheath-core configuration, where the polyethylene component forms the sheath.

[0039] While other materials may be useful in creating elastic structures, the stiffness of the PET core component in the sheath-core fiber configuration is considered useful in imparting elasticity to the upper and lower nonwoven fabrics. In a synergistic combination, the PE sheath component, which has a lower melting temperature than the PET core component, can be used to provide interfiber melting / fusion bonding brought about by the heat treatment of the precursor butt. This can help provide tensile strength to the web in both MD and CD. Such interfiber bonding helps reduce slippage between fibers, thereby further contributing to imparting dimensional stability and resilience to the material, even when the material is wet.

[0040] When a relatively high weight fraction of polymer fibers is included, more connections can be formed within the structure through heat treatment. However, too many connections can impart greater stiffness to the upper and lower nonwovens than desired. For this reason, selecting the weight fraction of polymer fibers may involve prioritizing and balancing the competing need for stiffness and flexibility in the upper and lower nonwovens.

[0041] As described above, the upper and lower nonwoven fabrics may further contain polymer fibers that increase the elasticity of the upper and lower nonwoven fabrics. The elastic polymer fibers can help the upper and lower nonwoven fabrics maintain permeability and compression recovery. In another configuration, the upper and lower nonwoven fabrics may contain elastic polymer fibers having various cross-sections, e.g., circular and hollow spiral, and / or elastic fibers having various sizes.

[0042] The polymer fibers may be elastic and may be spun from any suitable thermoplastic, such as polypropylene (PP), polyethylene terephthalate (PET), or other suitable thermoplastics known in the art. The average staple length of the elastic polymer fibers may be greater than about 10 mm, or in the range of about 20 mm to about 100 mm, about 30 mm to about 50 mm, or about 35 mm to about 50 mm. The thermoplastic polymer fibers may have any suitable structure or shape. For example, the elastic polymer fibers may be circular, or may have other shapes such as spiral, wavy ellipse, trefoil, wavy ribbon, and so on. Furthermore, the elastic polymer fibers may be solid, hollow, or multi-hollow. The elastic polymer fibers may be solid and round. In other preferred examples, the elastic polymer fibers may include polyester / co-extruded polyester fibers. Other preferred examples of elastic polymer fibers include two-component fibers, such as polyethylene / polypropylene, polyethylene / polyethylene terephthalate, and polypropylene / polyethylene terephthalate two-component fibers. These two-component fibers may have a sheath / core structure.

[0043] The elastic polymer fibers may be polyethylene terephthalate (PET) fibers or other suitable non-cellulose fibers known in the art. PET fibers may be given any suitable structure or shape. For example, PET fibers may be circular, or have other shapes such as helical, wavy elliptical, trefoil, wavy ribbon, hollow helical, and so on. PET fibers may be solid, hollow, or multi-hollow. In one particular example, PET fibers may have a hollow cross-section and may have a curled or helical structure along their length. Optionally, the elastic polymer fibers may be helically crimped or flatly crimped. The elastic polymer fibers may have an average crimp value of about 4 to about 12 crimps / inch (cpi), about 4 to about 8 cpi, about 5 to about 7 cpi, or about 9 to about 10 cpi. Specific, non-limiting examples of elastic polymer fibers are available from Wellman, Inc. (Ireland) under trademarks H1311 and T5974. Other examples of suitable elastic polymer fibers are disclosed in U.S. Patent No. 7,767,598.

[0044] The rigid polymer fibers and elastic polymer fibers must be carefully selected. For example, the chemical properties of the components forming the rigid polymer fibers and elastic polymer fibers may be similar, but the elastic polymer fibers must be selected such that the melting point of their constituent material is higher than the melting point of the bondable component of the rigid polymer fibers. Otherwise, during heat treatment, the elastic polymer fibers may bond to the rigid polymer fibers (or vice versa), potentially forming an excessively rigid structure. If the rigid polymer fibers include two-component fibers, for example, core-sheath constituent fibers with a sheath component having a relatively low melting temperature at which fusion bonding occurs, to avoid the above risk, the elastic polymer fibers may include only the constituent chemicals of the core, which may be a polymer with a relatively high melting temperature.

[0045] Nonwoven fabric performance can be influenced by a combination of the selection of nonwoven fiber polymers, fiber properties, and how the fibers are arranged or connected. The choice of nonwoven fabric can affect the ability of an absorbent article to recover its shape in response to compressive, bending, and stretching forces that occur during use due to body movement. If the fibers are short fibers (less than approximately 10 mm), they are likely to rearrange irreversibly under stretching and compressive forces. Rearranging of fibers in the fiber matrix (changing their orientation / state) dissipates tensile (stretching) or compressive forces, and as a result, the energy used to influence deformation is not available for recovery to the original shape. Longer fiber networks (typically longer than approximately 10 mm but less than approximately 100 mm) can dissipate the tensile / compressive forces typical of body movement along the length of the fibers and throughout the entire structure. As a result, the applied forces are available to restore the structure to its original state. Longer fibrous network structures composed of finer fibers (approximately 15 microns to less than 20 microns and less than 2.0 DTex) are more easily stretched and compressed. As a result, the fluff / AGM structure can be deformed more easily (and to a greater extent), but the energy associated with these deformations is relatively small and insufficient to return the structure to its original state. Thicker fibers, such as those exceeding approximately 2.0 DTex to 10 DTex, are flexible under bodily force but provide sufficient fiber and web recovery energy to return the structure to its original state.

[0046] From a structural standpoint, the fiber configuration arrangement in long-fiber network structures can affect the performance of absorbent articles containing these nonwovens. Long-fiber webs of thicker fibers are typically bulkier than conventional thin spunbond nonwoven webs, which consist of continuous fine fibers that are closely spaced and physically bonded together. By creating webs of thicker fibers configured with a more randomized orientation, which can be achieved through carding, water entanglement, and needling, the fibers can be stretched and compressed, thereby allowing them to temporarily adjust their configuration (spaces between fibers exist for these arrangements) and bear / store deformation forces, this energy being available to restore the structural shape.

[0047] Furthermore, thinner synthetic fibers (less than approximately 2.0 DTex), such as BiCo and PP fibers commonly found in spunbond, are densely spaced, aligned relatively parallel to each other, and tightly bonded together. These bonded fibers within the spunbond web are interconnected (by densely spaced point bonds) such that, under tension (stretching), the polymer-level fibers are forced to stretch, which permanently rearranges the polymer chains within the fibers, resulting in the fibers themselves potentially remaining permanently stretched (permanently strained) and no longer being able to return to their original state.

[0048] In some configurations, the polymer fibers in the upper nonwoven layer and the polymer fibers in the lower nonwoven layer may be different. In some configurations, the polymer fibers in the upper nonwoven layer and the polymer fibers in the lower nonwoven layer may be the same.

[0049] Examples of suitable nonwoven materials include, but are not limited to, the following: (i) a 40gsm carded elastic nonwoven material manufactured by Yanjan China (material code; ATB Z87G-40-90), which is a carded nonwoven composed of a blend of 60% 2DTex and 40% 4DTex BiCo(PE / PET) fibers. These fibers are bonded together (ATB = "hot" air bond) to form a wet elastic network structure. The basis weight of the material is 40gsm and it has a caliper of approximately 0.9 mm (under 7 kPa). Although not limited by theory, due to the presence of 4DTex BiCo fibers and the interfiber-bonded BiCo network structure, the material exhibits low permanent strain (less than approximately 0.013 mm / mm) and sufficient dry recovery energy (approximately 0.03 N) in wet and dry CD ultra-high sensitivity three-point bending methods. * It is considered to have a length greater than 0.013 mm. (ii) A 55 gsm elastic spunlace material manufactured by Sandler Germany (material code: 53FC041001), which is a water-flow entangled nonwoven fabric produced by water-flow entanglement using a carding process (as described above for the nonwoven fabric), followed by an upward drying process (as described in U.S. Patent Publication No. 2020 / 0315873(A1)) that produces both entangled and BiCo-bonded elastic reticular structures. It contains a fiber blend of 30% 10DTex HS-PET, 50% 2.2DTex BiCo(PE / PET), and 20% 1.3DTex rayon. Thus, this material exhibits low permanent strain (less than approximately 0.013 mm / mm) and sufficient drying recovery energy (approximately 0.03 N) in wet and dry CD ultra-high sensitivity three-point bending methods. *(iii) A water-flow entangled nonwoven fabric produced by Sandler Germany (material code: 53FC041005 opt82), which is produced by water-flow entanglement through a carding process (such as the nonwoven fabric described above) and a subsequent rising drying process (such as described in U.S. Patent Publication No. 2020 / 0315873(A1)) that produces both entanglement and a BiCo-bonded elastic lattice structure. This material contains a fiber blend of 60% 5.8DTex BiCo(PE / PET), 20% 3.3DTex trefoil-shaped "structure" rayon, and 20% 1.3DTex rayon. Thus, this material exhibits low permanent strain (less than about 0.013 mm / mm) and sufficient drying recovery energy (about 0.03 N) in wet and dry CD ultra-high sensitivity three-point bending methods. * It has a thickness of over mm. This material contains 40% rayon, which can soften when wet, but the use of structural trifoliate rayon fibers can help improve structural stability in wet conditions.

[0050] In combination with adjusting pore size, volume, and number by selecting appropriate fiber size, basis weight, and degree of compaction, manufacturers may desire to select fiber components to obtain specific surface chemical properties, e.g., fibers with hydrophobic or hydrophilic surfaces, or blends of different fibers and / or fibers with z-directional layering or gradients. Fibers with hydrophilic surfaces tend to attract and move along the aqueous components of menstrual fluid, in a manner that facilitates suction after discharge and rapid fluid acquisition. However, at the same time, the dominance of hydrophilic fiber surfaces in the top sheet may increase the tendency of the top sheet to reacquire fluid from the absorbent components below (re-wetting), which can cause an undesirable wet feeling for the user. On the other hand, fibers with hydrophobic surfaces tend to repel the aqueous components of menstrual fluid and / or resist the movement of fluid along their surfaces, thereby resisting suction, but also resisting re-wetting. Manufacturers may desire to find the right balance when selecting constituent fibers with hydrophilic surfaces, fibers with hydrophobic surfaces, or blends and / or z-directional lamination for any particular product design, in combination with fiber size, fiber reinforcement level, and the resulting top sheet pore size, volume, and number.

[0051] As shown in Figure 3, the inner core layer 200 is positioned between the upper nonwoven layer 210 and the lower nonwoven layer 220. The inner core layer 200 is manufactured by the air-lay method. A flow of cellulose fibers and AGM is carried by a high-speed airflow and deposited into three-dimensional pockets on a rotational molding drum with a vacuum below to draw the cellulose and AGM into pockets in a laydown station. These molded pockets provide the actual physical shape of the absorbent core structure. The upper or lower nonwoven may be introduced onto the molding drum first, and under vacuum, the upper or lower nonwoven is stretched into a three-dimensional pocket shape. In this case, the flow of cellulose and AGM material is deposited directly onto the upper (or lower) nonwoven material at the molding station. Before entering the molding station, the nonwoven is coated with an adhesive to more firmly bond the cellulose and AGM to the nonwoven layer. Upon exiting the laydown section, the second remaining nonwoven layer is combined with the nonwoven supporting the cellulose and AGM layers exiting the laydown section. This second remaining nonwoven (either the upper or lower nonwoven, depending on which nonwoven passes through the laydown section) is pre-coated with adhesive to enable a periphery seal and to better integrate the cellulose and AGM without obstructing the flow of liquid into the cellulose and AGM matrix. In an alternative method, the nonwoven is not initially introduced into the molding station, and the cellulose and AGM mass is held on a molding drum under vacuum until discharged onto either the upper or lower nonwoven layer coated with adhesive as detailed above, and then sealed with the second remaining nonwoven to form an absorbent core structure. The widths of the upper and lower nonwoven webs are selected to be wider than the maximum width of the molded cellulose and AGM matrix, thereby enabling an effective periphery seal where the two nonwovens connect at least on the leftmost and rightmost sides of the absorbent core structure.

[0052] The inner core layer may contain one of a wide variety of liquid-absorbent materials widely used in disposable absorbent articles, such as crushed wood pulp, commonly known as air felt. One suitable absorbent core material is the air felt material available from Weyerhaeuser Company (Washington, USA) under code number FR516. Other suitable liquid-absorbent materials used for the absorbent core include crepe cellulose wadding, meltblown polymers including coform, synthetic fibers such as chemically hardened, modified, or crosslinked cellulose fibers or crimped polyester fibers, peat moss, cotton, bamboo, absorbent polymer materials, or any equivalent materials or combinations thereof, or mixtures thereof.

[0053] Absorbent polymer materials for use in absorbent articles typically include water-insoluble, water-swellable, hydrogel-forming, cross-linked absorbent polymers that can absorb large amounts of liquid and retain such absorbed liquid under moderate pressure.

[0054] The absorbent polymer material for the absorbent core according to this disclosure may include superabsorbent particles, also known as “superabsorbent material” or “absorbent gelling material.” Typically, the absorbent polymer material in particulate form may be selected from polyacrylates and polyacrylate-based materials, such as partially neutralized crosslinked polyacrylates. The term “particles” refers to granules, fibers, flakes, spheres, powders, plates, and other shapes and forms known to those skilled in the art of superabsorbent particles. In some embodiments, the superabsorbent particles may be in the form of fibers, i.e., elongated needle-shaped superabsorbent particles.

[0055] In some configurations, the inner core layer may include cellulose fibers and superabsorbent particles. The inner core layer may include cellulose fibers in any of the following ranges: about 50 wt% to about 85 wt%, about 55 wt% to about 80 wt%, or about 60 wt% to about 75 wt% of the inner core layer. The inner core layer may include superabsorbent particles in any of the following ranges: about 15 wt% to about 50 wt%, about 20 wt% to about 40 wt%, or about 25 wt% to about 35 wt% of the inner core layer. Preferably, the inner core layer may include cellulose fibers in the range of about 125 gsm to about 400 gsm.

[0056] In some configurations, the inner core layer may include from about 50% to about 85% cellulose fibers and from about 15% to about 50% superabsorbent particles. The resulting absorbent core structure has a bulk density of about 0.045 g / cm 3 to about 0.15 g / cm 3 , and / or 0.045 g / cm 3 to 0.12 g / cm 3 . The absorbent article may have a bulk density of about 0.045 g / cm 3 to about 0.16 g / cm 3 .

[0057] The absorbent core structure may be compressed and may return to its original shape after the compression process. A suitable absorbent core structure has a low force (low resistance) required for compression, and the structure can return to its shape when the user periodically compresses it and releases the compression force with various body movements. To achieve this, the structure maintains sufficient recovery energy following multiple cycles of periodic compression. Without sufficient recovery energy, the structure remains in a compressed, clustered state with insufficient force (stored energy) to return to its original shape.

[0058] As shown in Figures 1, 2A, 2B, 4, and 5, the absorbent core structure may include a plurality of structural connection points 15. The structural connection points 15 may be symmetrical and / or asymmetrical, and may be any shape, including but not limited to circular, elliptical, heart-shaped, diamond-shaped, triangular, square, star-shaped, and / or X-shaped. The structural connection points 15 may be on the absorbent article and / or on the absorbent core structure. In some configurations, the structural connection points are approximately 2 mm apart. 2 ~about 5mm 2 The bonding area may be approximately 0.5% to 5%, or 0.75% to 4.5%, or 1% to 4%, of the absorbent core structure when measured according to the structural bonding site pattern spacing and area measurement method. In some configurations, the total structural bonding area may be approximately 1% to 4% of the absorbent article when measured according to the structural bonding site pattern spacing and area measurement method. The average distance between structural bonding sites may be approximately 10 mm to 32 mm. In some configurations, the average distance between structural bonding sites may be greater than approximately 20 mm. In some configurations, the structural bonding sites may have a maximum width of approximately 1 mm to 6 mm, approximately 1.5 mm to 5 mm, or approximately 2 mm to 4 mm. While not limited by theory, the average distance between these structural connection points and / or the size of these structural connection points are thought to help maintain the structural integrity of the absorbent core structure without creating undesirable stiffness that could impair the absorbent article's ability to conform to the body.

[0059] In some configurations, structural bonding sites may be distributed across the absorbent article and / or absorbent core structure, or they may be concentrated in each region of the absorbent article and / or absorbent core structure. In some configurations, structural bonding sites may be concentrated in the intermediate regions of the absorbent article and / or absorbent core structure. In some configurations, the intermediate regions of the absorbent article and / or absorbent core structure may not contain structural bonding sites, but may be surrounded by structural bonding sites and / or embossed areas.

[0060] In some configurations, the structural bonding site 15 may bond the top sheet 110, the upper nonwoven fabric layer 210, the absorbent core structure 10, and the lower nonwoven fabric layer 220.

[0061] A suitable absorbent article and / or absorbent core structure may include an upper nonwoven fabric layer and a lower nonwoven fabric layer that are closer to each other in the Z direction at structural bonding sites but are not fused to each other. Since these structural bonding sites are not fused to each other, they may not be permanent in nature, and rather materials may intermingle within the structural bonding sites. In some configurations, the structural bonding sites may not substantially contain fusion bonds.

[0062] The shape of the structural connection points can be any shape, but preferred shapes may be more intricate, such as asymmetrical shapes (compared to simple dots).

[0063] The absorbent article 20 may be elastic and conformable, and may provide excellent comfort during use without aggregation and / or compression. The absorbent article may be exposed to physical force and may return to its original state. The absorbent article has a bending strength of approximately 0.07 to 0.30 N / mm when measured by the wet and dry CD and MD three-point bending method. 2 , about 0.10~about 0.25N / mm 2 , or approximately 0.10 to approximately 0.20 N / mm 2 It may have a dry modulus of CD.

[0064] The absorbent article may have a dry caliper of approximately 2.0 mm to 6.0 mm, or approximately 2.0 mm to 4.5 mm, or approximately 2.50 mm to 4.0 mm, or approximately 2.75 mm to 3.5 mm, when measured according to the wet and dry CD and MD3-point method. In some configurations, the absorbent article has a N / mm² of approximately 0.07 to 0.30 N / mm² when measured according to the wet and dry CD and MD3-point method. 2The dry modulus of CD and dry caliper of approximately 2.0 mm to 4.5 mm, or approximately 0.10 to 0.25 N / mm 2 CD dry modulus and dry caliper of approximately 2.50 mm to 4.0 mm, or approximately 0.10 to 0.20 N / mm 2 The CD dry modulus may be approximately 2.75 mm to approximately 3.5 mm and the dry caliper may be approximately 3.5 mm. The absorbent article has a dry modulus of approximately 10.0 to approximately 30.0 N when measured by the wet and dry CD and MD three-point bending method. * mm 2 , or approximately 10.0 to approximately 25.0 N * mm 2 , or approximately 10 to approximately 20N * mm 2 , or approximately 13 to 20 N * mm 2 It may have a CD dry bending stiffness of approximately 10.0 to 30.0 N when measured according to the wet and dry CD and MD three-point method. Particularly suitable absorbent articles have a CD dry bending stiffness of approximately 10.0 to 30.0 N. * mm 2 The dry bending rigidity of the CD and the dry caliper of approximately 2.5 mm to 4.0 mm, or approximately 10 to 25 N * mm 2 The dry bending rigidity of the CD and the dry caliper of approximately 2.5-4.0 mm, or approximately 13-30 N * mm 2 Examples include those with a CD dry bending rigidity and a dry caliper of approximately 2.75 mm to 3.5 mm.

[0065] Absorbent materials have a saturation of approximately 1.0 to 3.5 N. * mm, or approximately 1.5 to 3.0 N * mm, or approximately 1.5 to 2.8 N * It may have a fifth-cycle wet recovery energy of mm. Particularly preferred absorbent articles are about 1.0 to 3.5 N. * The fifth-cycle wet recovery energy is mm and the fifth-cycle wet recovery percentage is approximately 29% to 40%, or approximately 1.5 to 3.0 N. * The fifth cycle wet recovery energy is mm and the fifth cycle wet recovery percentage is approximately 29% to 40%, or approximately 1.5 to 2.75 N. *It may have a fifth-cycle wet recovery energy of mm and a fifth-cycle wet recovery percentage of approximately 29% to 40%.

[0066] Absorbent articles containing the disclosed absorbent core structure may also need to deliver a dry feel to the consumer after fluid addition, as measured by the light-touch re-wetting method. Absorbent core structures and absorbent articles that satisfy the above characteristics are designed to conform more closely, more completely, comfortably and gently to the wearer's complex anatomical genital shape. Thus, such absorbent articles may also need to be dry to the touch after excretion so as not to irritate sensitive genital tissue. Accordingly, absorbent articles described herein may also maintain a light-touch re-wetting value of less than about 0.15 grams or less than about 0.12 grams, or about 0 to about 0.15 grams or about 0 to about 0.12 grams.

[0067] As shown in Figures 2A and 2B, the absorbent article 20 further comprises a chassis 100 having an absorbent core structure 10. The absorbent core structure 10 and / or inner core layer 200 may have a substantially hourglass shape. However, any preferred shape may be used. Some examples include an offset hourglass (where one end is wider than the opposite end and the narrow central section between these ends) and a bicycle seat shape (where one end and the central section are narrower than the second end). The side edges 120 and 125 may follow the overall contour of the absorbent core. Therefore, if the absorbent core structure has an hourglass shape, the side edges of the absorbent articles 120 and 125 may also be configured and arranged in an hourglass shape. However, the side edges 120 and 125 may also be generally straight or slightly curved so as not to follow the contour of the absorbent core structure. Further details are described below. The absorbent article 20 may be symmetrical with respect to the longitudinal center line 80, or it may be asymmetrical with respect to the longitudinal center line 80. Similarly, the absorbent article 20 may be symmetrical with respect to the transverse center line 90, or it may be asymmetrical with respect to the transverse center line 90.

[0068] Figure 6 shows a cross-sectional view of the absorbent article 20 according to the present disclosure. Figures 7A and 7B are top views of the absorbent article 20 according to the present disclosure. Figure 8 is an enlarged top view of the flexible binding channel region shown in Figure 7A. Figure 9 is a perspective view of the flexible binding channel region formed in the absorbent article. Figures 10A and 10B are partial cross-sectional views along line 10-10 in Figure 7A of an absorbent article including a flexible binding channel region according to various non-limiting embodiments of the present disclosure.

[0069] As described above and as shown in Figure 6, the absorbent article 20 may comprise a top sheet 110, a back sheet 130, and an absorbent core structure 10 positioned between the top sheet 110 and the back sheet 130. As shown in Figure 7A, the absorbent article 20 may also include one or more flexible bonded channel regions 160. At least some or all of the flexible bonded channel regions 160 may be permanent channels, meaning that the integrity of the channels is maintained at least partially in both dry and wet conditions. The flexible bonded channel regions 160 may be continuous depressions and / or comprise a series of individually compressed, closely spaced flexible bonded embossments.

[0070] The flexible coupling channel region 160 may have any configuration, for example, one or more linear shapes extending along the longitudinal centerline 80, one or more curved shapes generally along the longitudinal centerline 80, an ellipse, a rectangle, a triangle, a polygon, or any other shape. In some configurations, the flexible coupling channel region 160 may extend substantially longitudinally, meaning that each flexible coupling channel region extends more longitudinally than transversely, or (when measured after projection onto each axis) extends at least twice as much longitudinally. In some configurations, the flexible coupling channel region 160 may extend substantially transversely, meaning that each flexible coupling channel region extends more transversely than longitudinally, or (when measured after projection onto each axis) extends at least twice as much transversely as longitudinally.

[0071] In some configurations, the absorbent article 20 may include an inner flexible coupling channel region 161 and an outer flexible coupling channel region 162. The inner flexible coupling channel region 161 and the outer flexible coupling channel region 162 may function as a hinge structure in the absorbent article, which can allow the absorbent article to bend both longitudinally and transversely, thereby helping to better conform to the wearer's anatomical structure. The inner flexible coupling channel region 161 and the outer flexible coupling channel region 162 may also function as visual signals of the fluid barrier.

[0072] The inner flexible bonding channel region 161 may be curved and / or arc-shaped and may extend substantially parallel to the longitudinal centerline 80 of the absorbent article. In other configurations, the inner flexible bonding channel region 161 may be substantially straight. In some configurations, the inner flexible bonding channel region 161 may be concave toward the longitudinal centerline 80, for example, as shown in Figure 7B for a pair of inner flexible bonding channel regions 161, 161', and as a result they bend toward the longitudinal centerline 80. The inner flexible bonding channel region 161 may also be convex, or have any other preferred configuration, so as to bend away from the longitudinal centerline 80.

[0073] The absorbent article 20 and the absorbent core structure 10 each include a front end region 21, a rear end region 23, and an intermediate region 22 located between the front end region and the rear end region. The intermediate region 22 may include an intermediate use region 175. The internal flexible coupling channel region 161 may be located in the intermediate region 22, or a portion thereof, and in a portion of the front end region 21 and / or the rear end region 23. In some configurations, the internal flexible coupling channel region 161 may extend longitudinally from the front end region 21 to the rear end region 23. The absorbent article 20 may include one or more internal flexible coupling channel regions 161, for example, two, three, four, five, or six.

[0074] In some configurations, the internal flexible coupling channel region 161 may be located in at least the intermediate region 22, forming a closed loop that substantially encloses the intermediate work region 175, for example, as shown in Figure 7A. In some configurations, the absorbent article may comprise a pair of internal flexible coupling channel regions 161, 161', with at least a portion of the intermediate work region 175 positioned between the pair of internal flexible coupling channel regions. If the internal flexible coupling channel regions 161, 161' exist as a symmetrical pair with respect to the longitudinal centerline 80, the internal flexible coupling channel regions 161, 161' may be spaced apart from each other over their entire longitudinal dimension (for example, as shown in Figure 7B). In some configurations, the internal flexible coupling channel regions 161 may be spaced apart by a distance of at least about 10 mm so as not to impart local rigidity to the space between them. In some configurations, the distance between internal flexible bonding channel regions may be approximately 10 mm to 45 mm, approximately 12 mm to 30 mm, or approximately 15 mm to 25 mm when measured parallel to the lateral centerline 90 from the inner edge of one internal flexible bonding channel region to the inner edge of the opposing internal flexible bonding channel region.

[0075] The absorbent article may include structural bonding sites 15 and flexible bonding channel regions 160. In some configurations, the intermediate use region 175 may not substantially have structural bonding sites 15, as shown in Figure 7A, and may be at least partially surrounded by regions of structural bonding sites and / or flexible bonding channel regions. It should be understood that the absorbent article shown in Figure 7B may also include structural bonding sites 15 as described above.

[0076] As shown in Figures 7A and 7B, the absorbent article 20 may include an outer flexible coupling channel region 162 to further increase the flexibility and fit of the absorbent article and / or to help provide a visual signal of the fluid barrier. The above description of the flexible coupling channel region 160 and / or the inner flexible coupling channel region 161 can be equally applied to the outer flexible coupling channel region 162. In some configurations, to reduce the risk of fluid leakage, the outer flexible coupling channel region 162 may be located between the periphery 10a of the absorbent core structure and the periphery 200a of the inner core layer, for example, as shown in Figure 7A. The outer flexible coupling channel region 162 may be located outside the periphery 200a of the inner core layer and may at least partially surround the inner core layer 200. In such configurations, the outer flexible coupling channel region 162 can compress the top sheet and the upper nonwoven layer toward the lower nonwoven layer, but the inner core layer is not present between them. In some configurations, the distance between the outer edge of the outer flexible binding channel region 162 and the periphery 10a of the absorbent core structure may be at least 3 mm, or about 3 mm to about 8 mm or about 5 mm to about 6 mm. In other configurations, as shown in Figure 7B, for example, the outer flexible binding channel region 162 may be located inside the periphery 200a of the inner core layer, and the top sheet, upper nonwoven layer, and inner core layer may be compressed toward the lower nonwoven layer.

[0077] In some configurations, the outer flexible coupling channel region 162 may include a closed loop surrounding the inner flexible coupling channel region 161. In such configurations, as shown in Figure 7A, the distance "X" between the inner flexible coupling channel region 161 and the outer flexible coupling channel region 162 may be approximately 10 mm to 30 mm, approximately 12 mm to 25 mm, or approximately 15 mm to 20 mm when measured parallel to the transverse centerline 90 from the inner edge of the outer flexible coupling channel region 162 to the outer edge of the inner flexible coupling channel region 161. In other configurations, the outer flexible coupling channel region 162 may include a pair of outer flexible coupling channel regions located outside the inner flexible coupling channel region 161. In such configurations, the distance between the inner flexible binding channel region 161 and the outer flexible binding channel region 162 may vary along the longitudinal lengths of the inner and outer flexible binding channel regions 161 and 162, and the maximum distance X' between the inner and outer flexible binding channel region 161 and 162 is approximately 4 mm to 15 mm, approximately 6 mm to 12 mm, or approximately 8 mm to 10 mm when measured parallel to the transverse centerline 90 from the outer edge of the outer flexible binding channel region 162 to the outer edge of the inner flexible binding channel region 161. In some configurations, the inner flexible binding channel region 161 may be concave and the outer flexible binding channel region 162 may be convex, which may help improve the fit of the absorbent article by allowing the intermediate region to be closer to the wearer's anatomical structure.

[0078] As shown in Figure 7B, the absorbent article may include one or more lateral auxiliary flexible coupling channel regions 170. The lateral auxiliary flexible coupling channel 170 may have elongated dimensions that are primarily oriented laterally, or it may be substantially perpendicular to the longitudinal centerline 80 of the absorbent article 20. The lateral auxiliary flexible coupling channel region 170 may function as a lateral hinge structure that allows the absorbent article to bend laterally and thereby conform to the wearer's anatomical structure, and / or function as a visual barrier mechanism. The description of the flexible coupling channel region 160 provided herein is equally applicable to the lateral auxiliary flexible coupling channel region 170. The lateral auxiliary flexible coupling channel region 170 may be located within the front end region 21, the middle region 22, and / or the rear end region 23. The lateral auxiliary flexible coupling channel region 170 may have any configuration, for example, one or more linear shapes extending along the lateral centerline 90, one or more curved shapes generally along the lateral centerline 90, an ellipse, rectangle, triangle, polygon, inverted V-shape, or any other shape. In some configurations, the lateral auxiliary flexible coupling channel region 170 may be located longitudinally outward of the outer flexible coupling channel region 162 and / or the inner flexible coupling channel region 161. The lateral auxiliary flexible coupling channel region 170 may have a length of about 10 mm to about 60 mm, about 15 mm to about 40 mm, or about 25 mm to about 35 mm when measured from the first end of the auxiliary flexible coupling channel region to the second end of the auxiliary flexible coupling channel region, following the curve of the auxiliary flexible coupling channel region. In some configurations, the lateral auxiliary flexible coupling channel region 170 may be separate from and isolated from the inner flexible coupling channel region 161 and the outer flexible coupling channel region 162, as shown in Figure 7B.

[0079] Referring further to Figure 7B, the absorbent article 20 may include a front flexible coupling channel region 190 located in the front end region 21, and / or a rear flexible coupling channel region 192 formed in the rear end region 23. The description of the flexible coupling channel region 160 provided herein can be equally applied to the front flexible coupling channel region 190 and / or the rear flexible coupling channel region 192. The front flexible coupling channel region 190 and the rear flexible coupling channel region 192 may be substantially U-shaped and may be located outside the inner flexible coupling channel region 161, the outer flexible coupling channel region 162, and / or the lateral auxiliary flexible coupling channel region 170. In some configurations, the front flexible coupling channel region 190 may extend from the front end region 21 to a position adjacent to the outer flexible coupling channel region 162 in the intermediate region 22. In some configurations, the rear flexible bond channel region 192 may extend from the rear end region 23 to a position adjacent to the outer flexible bond channel region 162 within the intermediate region 22. As shown, the front flexible bond channel region 190 and the rear flexible bond channel region 192 may be discontinuous, for example, separate, and may not be joined to the outer flexible bond channel region 162 or the inner flexible bond channel region 161. The front flexible bond channel region 190 and the rear flexible bond channel region 192 are thought to help provide comfort and conformity to the absorbent article 20 in the front end region 21 and the rear end region 23.

[0080] The flexible bond channel region 160 may be continuous or discontinuous. In this specification, “discontinuous” means that the flexible bond channel region may be separated by a non-channel region (i.e., a region where no channel is formed). The distance between two continuous flexible bond channel regions (i.e., the length of the non-channel portion) may be varied depending on the product design. While not limited by theory, it is conceivable that having a non-channel region, for example, between the end of the front flexible bond channel region 190 and the end of the outer flexible bond channel 162, or between the inner flexible bond channel region 161 and the outer flexible bond channel region 162, may help avoid the generation of undesirable stiffness and may help provide improved flexibility and fit for the absorbent article.

[0081] In some configurations, the inner flexible binding channel region 161 and / or the outer flexible binding channel region 162 may be continuous. In some configurations, the inner flexible binding channel region 161 may be discontinuous, and the outer flexible binding channel region 162 may be continuous. The flexible binding channel region 160 may have a minimum channel length of approximately 50 mm when measured from the first end of the flexible binding channel region to the second end of the flexible binding channel region along the curve of the flexible binding channel region. Although not limited by theory, if the flexible binding channel region is less than approximately 50 mm, it is thought that the length of the flexible binding channel region may be insufficient to provide enough multidirectional flexibility to create the desired flexure in the absorbent article in order to allow the absorbent article to fit snugly to the body. It is thought that a flexible binding channel region with a channel length of at least 50 mm can sufficiently influence adjacent non-channel regions, and as a result, the absorbent article can conform and fit snugly to the body. The flexible bonding channel region 160 may have a height of approximately 50 mm to 400 mm, approximately 60 mm to 350 mm, approximately 75 mm to 300 mm, or approximately 100 mm to 200 mm.

[0082] In some configurations, the inner flexible bonded channel region 161 may form a closed loop defining a central channel zone 180, as shown, for example, in Figure 7A. The central channel zone 180 may have a longitudinal length "LZ" measured parallel to the longitudinal axis from a first outermost point of the inner flexible bonded channel region 161 to a second outermost point opposite the longitudinal direction of the inner flexible bonded channel region 161. The longitudinal length "LZ" of the central channel zone may be approximately 50% to 90% of the inner core longitudinal length "LC", or approximately 60% to 75% of the inner core longitudinal length "LC".

[0083] In some configurations, the flexible coupling channel region 160 may have a channel area of ​​approximately 10 to 20% of the inner core layer area.

[0084] Referring to Figure 8, the flexible bond channel region 160 may include a plurality of flexible bond embossments 160a that are densely arranged but spaced apart from one another. The flexible bond land region 163 is positioned between adjacent flexible bond embossments 160a. The flexible bond embossments 160a may have an embossment length "L" of about 1.0 mm to about 4.0 mm, about 1.5 to about 3.75 mm, or about 2.0 to about 3.5 mm when measured according to the flexible bond embossment length method. The flexible bond channel embossments 160a may have a width "W1" of about 1.0 to about 3.0 mm, about 1.25 to about 2.5 mm, or about 1.5 to about 2.0 mm on the upper surface of the top sheet. The length "S" of the flexible bond land region 163 between adjacent flexible bond embossments 160a may be approximately 0.5 mm to 4 mm, approximately 1.0 mm to 3 mm, or approximately 1.5 mm to 2.5 mm, when measured according to the flexible bond land region length method. Although not limited by theory, it is believed that combinations of the length and width of the flexible bond embossments, and / or the length "S" of the flexible bond land region between the flexible bond embossments, can allow the flexible bond channel region to bend / flex in multiple directions, providing a consumer-preferred visual barrier while still maintaining the overall flexibility and conformability of the absorbent article.

[0085] In some configurations, the flexible bonding embossing 160a may extend substantially parallel to the longitudinal centerline 80 of the absorbent article. In other configurations, the flexible bonding embossing 160a may extend substantially parallel to the transverse centerline 90 of the absorbent article.

[0086] In some configurations, the flexible bond embossments 160a may be evenly spaced apart from each other. In some configurations, at least a portion of the flexible bond embossments 160a may be grouped into clusters of two, three, or four or more flexible bond embossments, as shown in Figure 7B, with spacing between clusters of approximately 2 mm to 8 mm, or approximately 3 mm to 6 mm. Although not limited by theory, such clusters of flexible bond embossments may help provide increased flexibility to the flexible bond channel region in both the lateral and longitudinal directions, and / or help improve fluid handling by allowing fluid to flow through the gaps between clusters to other regions of the absorbent core structure.

[0087] Figure 9 shows a perspective view illustrating a flexible bonding channel region 160 in an absorbent article, which includes a plurality of flexible bonding embossments 160a. The thickness "T2" of the flexible bonding land region 163 may be about 50% to about 70% of the thickness "T" of the absorbent article. Although not limited by theory, it is thought that reducing the thickness of the absorbent article in the z direction along the length of the flexible bonding channel region (including the flexible bonding land area) may help create an effective preferential bending line that allows the absorbent article to conform closely to the body in a preferred position, and / or help create an effective visual barrier feature that is easily visible to the user. A non-channel region 172 is located adjacent to the flexible bonding channel region 160. The flexible bonding embossments 160a may have an embossed area of ​​about 22% to about 65% of the area of ​​the flexible bonding channel region.

[0088] In contrast to the flexible binding channel regions described herein, current absorbent articles for menstrual applications may include a series of punctate depressions, thereby allowing the material between the depressions in the z-direction to recover to a degree that is dominant over the uncompressed thickness of the non-channel regions. In such structures, the channel depth between the depressions may be less than about 10% to about 25% of the channel depth at the embossed points. While not limited by theory, such punctate depressions may not form effective flex lines for closely conforming the article to the body. Other current absorbent articles may include small physical binding points with relatively large gaps between them. While not limited by theory, if the physical binding points are relatively small (e.g., less than about 0.5 mm wide) and sufficiently spaced apart (e.g., more than about 1 to 4 mm), these physical binding points may not be sufficient to reproducibly drive the fit / bend direction of the absorbent article. To establish a reproducible and effective fit / bending direction, sufficient mass should be displaced in the z-direction, and it is considered that this should be consistently thinned throughout a substantial portion of the channel region to effectively drive desirable consistent bending characteristics.

[0089] Typically, the flexible bonded channel region 160 may be formed by applying compressive force to the top sheet 110, the upper nonwoven layer 210, the inner core layer 200, and the lower nonwoven layer 220. The top sheet in the flexible bonded channel region is pushed down into the absorbent core structure, and the material of the top sheet and the absorbent core structure is compressed at and below the bottom of the flexible bonded channel region. This operation (often called the “embossing process”) results in the flexible bonded channel region of the absorbent article having a relatively higher density than the non-channeled region. As a result of the compression, the flexible bonded channel region 160 may be formed to have an elongated recess, such as a modified trough shape, having a pair of opposing side walls 165 and a bottom surface 166, as shown in Figures 10A and 10B.

[0090] In some configurations, compressive forces are applied to the top sheet 110, the upper nonwoven layer 210, and the lower nonwoven layer 220 to create a flexible bonded channel region 160 in an area without an inner core layer. The flexible bonded channel region of this disclosure can be formed by any structure and process known in the art.

[0091] The flexible bonded channel region 160 may be formed by applying a uniform (or single-level) compressive force. In some configurations, the flexible bonded channel region 160 may be formed by applying two or more levels of compressive force, thereby forming a stage channel structure, such as that disclosed in U.S. Patent No. 6,563,013. In a stage channel configuration, the flexible bonded channel region may comprise opposing side walls, a first portion forming a first bottom surface, and a second portion forming a second bottom surface, the second bottom surface being below the first bottom surface, and the second portion may be separate or surrounded by the first portion.

[0092] Referring to Figures 10A and 10B, the surface 20A of the absorbent article 20 facing the wearer may include a flexible bonded channel region 160 having a dry channel depth "D" when measured according to the flexible bonded channel depth method. The dry channel depth "D" of the flexible bonded channel region 160 may be about 1.0 mm to about 4.0 mm, about 1.5 mm to about 3.5 mm, or about 2.0 mm to about 3.0 mm. The flexible bonded channel region may have a channel depth of at least 1.0 mm. In some configurations, the dry channel depth "D" of the flexible bonded channel region 160 may be about 20% to about 80% of the thickness "T" of the absorbent article, or about 25% to about 70% of the thickness "T" of the absorbent article. The thickness of the absorbent article is measured according to the flexible bonded channel depth method. Although not limited by theory, the flexible bonded channel region 160 having the dry channel depth described herein is thought to provide improved body fit, a good fluid barrier, and / or an aesthetic visual barrier effect.

[0093] Referring to Figure 10B, in some configurations, the outer surface 20B of the absorbent article 20 may have a flexible bond recess region 164 having a dry channel depth "D1" when measured from the peripheral region of the outer surface 20B to the bottom wall 168 of the flexible bond recess. The dry channel depth "D1" of the flexible bond recess region 164 may be about 1.0 mm to about 4.0 mm, about 1.5 mm to about 3.5 mm, or about 2.0 to about 3 mm. In certain configurations, the dry channel depth "D1" of the flexible bond recess region 164 on the outer surface 20B may be about 15% to about 80% of the thickness "T" of the absorbent article, or about 25% to about 70% of the thickness "T" of the absorbent article. The outer surface 20B of the absorbent article 20 does not need to be directly contacted by the embossing apparatus during embossing, but a flexible bond recess region 164 may be generated. While not limited to theory, it is conceivable that the flexible bond recess region 164 on the outer surface 20B may be formed from the stretching of the top sheet and the absorbent core structure. Following embossing and removal of the embossing apparatus, the recovery of the material forming the top sheet and the absorbent core structure can be achieved by pulling or tensing the material back toward the surface 20A facing the wearer.

[0094] The flexible bonding channel region 160 may have a channel thickness "T1" of less than approximately 2.5 mm, or approximately 0.5 mm to approximately 2.5 mm, or approximately 1.0 mm to approximately 2.0 mm.

[0095] The flexible bonded channel region 160 may have a channel width "A" of approximately 1.0 mm to approximately 3.0 mm, approximately 1.25 mm to approximately 2.5 mm, or approximately 1.5 mm to approximately 2.0 mm at the base of the channel, when measured according to the flexible bonded channel width method. The flexible bonded recess region 164 may have a lateral channel width "A'" of approximately 1.0 mm to approximately 3.0 mm, approximately 1.25 mm to approximately 2.5 mm, or approximately 1.5 mm to approximately 2.0 mm at the base of the recess.

[0096] In some configurations, the maximum width of the structural connection site 15 may be greater than the channel width "A" of the flexible connection channel region 160. Although not limited by theory, if the channel width "A" of the flexible connection channel region 160 is greater than the maximum width of the structural connection site 15, it is thought that the absorbent core structure and / or absorbent article may develop stiffness that may hinder their ability to closely conform to the body.

[0097] The flexible binding channel region 160 contains approximately 0.3 g / cm³ 3 Less than or approximately 0.05 g / cm³ 3 ~about 0.3g / cm 3 , or approximately 0.1 g / cm³ 3 ~Approx. 0.25g / cm 3 It may have a channel density of approximately 0.3 g / cm³, although this is not limited by theory. 3 A channel density of less than is thought to cause plastic deformation of the inner core layer, keeping the flexible bonded channel region compressed, but still allowing the flexible bonded channel region to bend in both the lateral and longitudinal directions.

[0098] The flexible bond channel region 160 may have a dry MD stiffness of less than approximately 0.04 N / mm, or approximately 0.005 to approximately 0.035 N / mm, or approximately 0.1 to approximately 0.030 N / mm, when measured according to the flexible bond channel MD stiffness method. Although not limited by theory, it is thought that flexible bond channel regions having a dry MD stiffness greater than approximately 0.04 N / mm may create stiffness that may hinder the ability of the absorbent core structure and / or absorbent article to conform tightly to the body simultaneously in both the longitudinal and transverse directions.

[0099] The flexible bond channel region 160 may have a dry flexible bond CD stiffness of approximately 0.005 N / mm to approximately 0.30 N / mm, or approximately 0.01 N / mm to approximately 0.25 N / mm. The flexible bond channel region may have a CD stiffness index of approximately 1.1 to approximately 3.0, approximately 1.2 to approximately 2.5, or approximately 1.5 to approximately 2.0.

[0100] Top sheet The top sheet 110 may be formed from any suitable nonwoven web or molded film material. Referring again to the figure, the top sheet 110 is positioned adjacent to the wearer-facing surface 20A of the absorbent layer 20 and may be bonded to the surface 20A and to the back sheet 130 by any suitable attachment or bonding method. The top sheet 110 and the back sheet 130 may be directly bonded to each other in the outer peripheral region around the absorbent core structure, or they may be indirectly bonded by directly bonding to the wearer-facing surface and the outer-facing surface of the absorbent article, or to any additional optional layer included in the absorbent article, respectively.

[0101] The absorbent article 20 may have any known or other effective top sheet 110, such as one that is conformable, soft to the touch, and non-irritating to the wearer's skin. Preferred top sheet materials include liquid-permeable materials that are comfortable when in contact with the wearer's skin and allow discharged menstrual fluid to rapidly permeate through them. Some preferred examples of top sheet materials include films, nonwovens, and laminated structures including, for example, film / nonwoven layers, film / film layers, and nonwoven / nonwoven layers.

[0102] Non-limiting examples of nonwoven web materials that may be suitable for use in forming the top sheet 110 include fibrous materials made from natural fibers, modified natural fibers, synthetic fibers, or combinations thereof. Several suitable examples are described in U.S. Patents No. 4,950,264, 4,988,344, 4,988,345, 3,978,185, 7,785,690, 7,838,099, 5,792,404, and 5,665,452.

[0103] The top sheet 110 may be flexible, soft to the touch, and non-irritating to the wearer's skin. Furthermore, the top sheet 110 may be liquid permeable so that liquids (e.g., urine, menstrual blood) can easily penetrate through its thickness. Some preferred examples of top sheet materials include films, nonwoven fabrics, and laminated structures including, for example, film / nonwoven layers, film / film layers, and nonwoven / nonwoven layers. Other exemplary top sheet materials and designs are disclosed in U.S. Patent Applications Publications 2016 / 0129661, 2016 / 0167334, and 2016 / 0278986.

[0104] In some examples, the top sheet 110 may include tufts as described in U.S. Patents No. 8,728,049, 7,553,532, 7,172,801, 8,440,286, 7,648,752, and 7,410,683. The top sheet 20 may have a pattern of individual hair-like fibrils as described in U.S. Patent No. 7,655,176 or 7,402,723. Additional examples of preferred top sheet materials are disclosed in U.S. Patents No. 8,614,365, 8,704,036, 6,025,535, and U.S. Patent Application Publication 2015 / 041640. Another preferred top sheet may be formed from a three-dimensional substrate as detailed in U.S. Patent Application Publication 2017 / 0258647. The top sheet may have one or more layers, as described in U.S. Patent Application Publications 2016 / 0167334, 2016 / 0166443, and 2017 / 0258651.

[0105] In some examples, the top sheet 110 may be formed from a spunbond web nonwoven web material comprising single-component continuous fibers, or alternatively, two-component or multi-component fibers, or a blend of single-component fibers spun from different polymer resins, or any combination thereof. The top sheet may also be a molded nonwoven top sheet, as disclosed in U.S. Patent Application Publication No. 2019 / 0380887.

[0106] To ensure that fluids in contact with the top surface (facing the wearer) of the top sheet move suitably and rapidly in the z-direction to the bottom surface (facing the outside) of the top sheet, where they can be drawn into the absorbent layer, it may be important to ensure that the nonwoven web material forming the top sheet has an appropriate weight / volume density, thereby reflecting the favorable presence of pores (also called "pores") in and between the constituent fibers through which fluids can move within the nonwoven material. In some situations, a nonwoven with fibers that are too densely compacted may have an insufficient number and / or volume and / or size of pores, and the nonwoven will hinder rather than facilitate rapid downward z-direction fluid movement. On the other hand, a nonwoven with fibers that are too large and / or not compacted to provide a certain level of opacity (for the purpose of concealing fluids absorbed into the layer below) and a considerable appearance may be perceived negatively by the user.

[0107] The caliper of the top sheet material may be controlled to balance the conflicting needs of opacity and loft (requiring a higher caliper) and the limited z-direction distance that the discharged fluid travels through the top sheet from the wearer-facing surface to the outward-facing surface in order to reach the absorbent core component below. Therefore, it may be desirable that the manufacturing of the top sheet material be controlled to produce top sheet material with calipers of approximately 0.20 mm to 1.0 mm, approximately 0.25 mm to 0.80 mm, or approximately 0.30 mm to 0.60 mm.

[0108] Supplemental top sheet (STS) In some situations, the STS layer may be included between the top sheet and the absorbent core structure, allowing the absorbent core structure to readily receive the sudden discharge of fluid, and after receiving it, to draw it up along the x and y directions and distribute it across the absorbent core structure below.

[0109] If STS is included, the STS may be a nonwoven fiber structure that may include cellulose fibers, noncellulose fibers (e.g., fibers spun from polymer resins), or blends thereof. To accommodate the folding and lateral gathering of the absorbent article 20 and the absorbent core structure 10, the STS may be formed from a relatively flexible (i.e., relatively low bending stiffness) material, as described herein.

[0110] Several specific examples of preferred STS compositions and structures, and combinations thereof with preferred topsheet compositions and structures, are described in U.S. Patent Applications Nos. 16 / 831,862, 16 / 831,854, 16 / 832,270, 16 / 831,865, 16 / 831,868, 16 / 831,870, and 16 / 831,879, and U.S. Provisional Patent Applications Nos. 63 / 086,610 and 63 / 086,701. Additional preferred examples are described in U.S. Patent No. 9,504,613, International Publication No. 2012 / 040315, and U.S. Patent Application Publication No. 2019 / 0021917.

[0111] In some configurations, the absorbent material may not have an auxiliary top sheet.

[0112] Back seat The backsheet 130 can be positioned beneath or adjacent to the outer surface of the absorbent core structure 10 and can be bonded to that surface by any preferred mounting method. For example, the backsheet 130 can be fixed to the absorbent core structure 10 by a uniform, continuous layer of adhesive, a patterned layer of adhesive, or an arrangement of separate lines, spirals, or dots of adhesive. Alternatively, the mounting method may include thermal bonding, pressure bonding, ultrasonic bonding, dynamic mechanical bonding, or any other preferred mounting mechanism, or a combination thereof. In other examples, it is intended that the absorbent core structure 10 is not directly bonded to the backsheet 130.

[0113] The backsheet 130 may be impermeable to or substantially impermeable to aqueous liquids (e.g., urine, menstrual fluid) and may be manufactured from a thin plastic film, but other flexible liquid-impermeable materials may also be used. As used herein, the term “flexible” refers to a material that is flexible and readily conforms to the general shape and contours of the human body. The backsheet 130 can prevent, or at least substantially prevent, fluid absorbed and contained within the absorbent core structure 10 from escaping to articles of the wearer’s clothing that may come into contact with absorbent articles 20, such as underwear and other clothing. However, in some examples, the backsheet 130 may be manufactured to allow vapor to escape from the absorbent core structure 10 (i.e., the backsheet is made to be breathable), while in other examples, the backsheet 130 may be manufactured not to allow vapor to escape (i.e., it is made to be non-breathable). Thus, the backsheet 130 may include a polymer film, such as a polyethylene or polypropylene thermoplastic film. Suitable materials for the backsheet 130 are, for example, thermoplastic films having a thickness of about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mil). Any suitable backsheet known in the art may be used in conjunction with the present invention.

[0114] Some preferred examples of materials suitable for forming backsheets are described in U.S. Patents Nos. 5,885,265, 4,342,314, and 4,463,045. Suitable single-layer breathable backsheets for use herein include, for example, those described in British Patents Nos. A2184389, A2184390, and A2184391, U.S. Patents Nos. 4,591,523, 3,989,867, and 3,156,242, International Publication No. 97 / 24097, and U.S. Patents Nos. 6,623,464, 6,664,439, and 6,436,508.

[0115] The backsheet 130 may have two layers, namely a first layer comprising a vapor-permeable perforated film layer and a second layer comprising a breathable microporous film layer, as described in U.S. Patent No. 6,462,251. Other suitable examples of double or multilayer breathable backsheets for use herein include those described in U.S. Patents No. 3,881,489, No. 4,341,216, No. 4,713,068, No. 4,818,600, European Patent Application Publications No. 203821, No. 710,471, No. 710,472, and No. 0793952.

[0116] Other features In some configurations, the absorbent article 20 may include an adhesive deposit to provide a mechanism for the user to adhere the absorbent article to the crotch area inside the underwear. When the absorbent article 20 is packaged for shipment, handling, and storage before use, the adhesive deposit may be covered with one or more sheets (not shown) of release film or paper, thereby covering / shielding the adhesive deposit from contact with other surfaces until the user removes the release film or paper and places the absorbent article in the underwear for wear / use.

[0117] In some configurations, the absorbent article 20 may include opposing wing portions 140, 150 (Figure 2A) on each side, extending laterally beyond the longitudinal edge of the absorbent portion of the absorbent article by a width dimension relatively larger than the width dimension of the front and rear portions of the absorbent article. Wings are now commonly provided on women's sanitary absorbent articles. As provided, they typically have an adhesive deposit applied to their outward-facing surface (the surface is outward before the absorbent article is placed in the user's underwear and the wings are applied). The wing portions may also include an adhesive deposit as described above, so that the user can wrap the wing portions around the inner edge through the leg opening of the underwear and adhere the wing portions to the outward-facing surface / underside of the underwear in the crotch area, providing auxiliary retaining support for the absorbent article and helping to protect the underwear from soiling in close proximity to the leg edge of the underwear.

[0118] Test method Target audience For any of the following methods in which not all constituent layers of the article are tested, the layer under test may be separated from the layers not being tested using cryospray as necessary.

[0119] Fracture strain method The force-displacement behavior of the sample is measured on a general-purpose constant-speed elongation test frame equipped with a load cell in which the measured force is within 1% to 99% of the cell's limit (a suitable instrument is the MTS Alliance with TestSuite Software, available from MTS Systems Corp. (Eden Prairie, MN), or an equivalent). The sample is subjected to tensile elongation at a constant speed (mm / sec) until fracture, and the fracture strain percentage is measured. All tests are conducted in a room conditioned at 23°C ± 3°C and 50% ± 2% relative humidity, and the test sample is conditioned in this environment for at least 2 hours prior to testing.

[0120] The fixtures used to grip the test specimens are lightweight (less than 80 grams) vise-type clamps having gripping surfaces of at least 40 mm wide semi-cylindrical steel versus rubber-coated steel. The fixtures are mounted on a universal test frame and aligned horizontally and vertically to one another.

[0121] The test specimens are prepared as follows: Test material is obtained by excising it from the absorbent article, if necessary. When excising the test material, care is taken not to contaminate or deform the material layer during the process. The test specimens are cut from an area of ​​the test material that does not contain folds or wrinkles. The test specimens are 100 mm long (parallel to the transverse axis of the article, or the intended transverse axis) and 25.4 mm wide (parallel to the longitudinal axis of the article, or the intended longitudinal axis). Five duplicate test specimens are prepared in the same manner.

[0122] The universal test frame is prepared as follows: The initial separation distance between grips is set to a nominal gauge length of 80 mm, and the crosshead is then zeroed. To ensure that there is no pre-tension in the specimen at the start of the test, the test frame is programmed to bring the grips closer together by an intentional 1 mm slack. (During this movement, the specimen slackens between the grips). The grips are then moved apart at a slackening rate of 1 mm / second until the slack preload exceeds 0.05 N. (At this point, the crosshead position signal is used to calculate the sample slack, adjusted gauge length, and define the strain as zero, i.e., 0.0). The grips are then moved apart at a rate of 1 mm / second until the sample breaks or exceeds the instrument's extension limit.

[0123] The test is performed by inserting the specimen into the grip so that its long axis is parallel to the movement of the crosshead and located at the center of that movement. The test is started and force ("load") and displacement data are continuously collected at a data acquisition rate of 100 Hz.

[0124] Create a graph of load (N) versus displacement (mm). Determine the peak load from the curve, and then determine the fracture sensitivity as follows: Determine the crosshead position at which the load signal decreases by 75% after reaching the peak load, and record this as the final specimen length (Lf) in units of 0.01 mm. Define the initial specimen length by the crosshead position when the loosening preload of 0.05 N is exceeded, and record this value as the initial specimen length (Li) in units of 0.01 mm. Calculate the fracture strain percentage as follows and record it in the nearest 1 percent unit. Fracture strain % = ((Lf - Li) / Li) * 100

[0125] Repeat this procedure for all five duplicate specimens in the same manner. Calculate the arithmetic mean of the fracture strain % of the five duplicate specimens and report it as fracture strain % in 1-percent increments.

[0126] Wet and dry CD and MD three-point bending method The bending properties of absorbent material test samples are measured on a general-purpose constant-speed elongation test frame equipped with a load cell in which the measured force is within 1% to 99% of the cell's limit (a suitable instrument is the MTS Alliance with TestSuite Software, available from MTS Systems Corp. (Eden Prairie, MN), or an equivalent). Tests are performed on both dry and wet specimens. The intent of this method is to simulate the deformation created in the xy plane by the wearer of an absorbent material during normal use. All tests are performed in a controlled room at 23°C ± 3°C and 50% ± 2% relative humidity.

[0127] The bottom stationary fixture consists of two cylindrical bars made of polished stainless steel, each 3.175 mm in diameter and 110 mm in length, mounted at each end using frictionless rolling bearings. These two bars are mounted horizontally, aligned front to back and parallel to each other, with their upper radii aligned vertically, and rotate freely around the diameter of the cylinder by frictionless bearings. Furthermore, the fixture allows the two bars to move horizontally away from each other on the track, thus creating a gap between them while maintaining the orientation of the bars. The upper fixture consists of a third cylindrical bar, also made of polished stainless steel, similarly 3.175 mm in diameter and 110 mm in length, mounted at each end using frictionless rolling bearings. When in position, the bars of the upper fixture are parallel to the bars of the lower fixture, aligned front to back, and positioned centered between the bars of the lower fixture. Both fixtures include integrated adapters suitable for fitting and securing in place at their respective positions on the universal test frame, so that the bars are perpendicular to the movement of the crossbeams of the test frame.

[0128] Set the gap ("span") between each bar of the lower fixture to 25mm ± 0.5mm (from the center of one bar to the center of the other), and align the center of the upper bar with the midpoint between each lower bar. Set the gauge (from the bottom of the upper bar to the top of the lower bar) to 1.0cm.

[0129] The thickness of the specimen ("caliper") is measured using a manual micrometer equipped with a clamp capable of applying a constant pressure of 0.1 psi ± 0.01 psi. The manual micrometer is a self-weight instrument with accurate readings to 0.01 mm. A suitable instrument is the Mitutoyo Series 543 ID-C Digimatic, available from VWR International, or an equivalent. The clamp is a circular, movable surface with a flat surface and a diameter of 25.4 mm or less. The specimen is supported by a horizontal, flat reference platform that is larger than the surface of the clamp and parallel to the surface of the clamp. Zero the micrometer relative to the horizontal, flat reference platform. Place the specimen on the platform and center it under the clamp. Lower the clamp by hand at a descent rate of 3 ± 1 mm / sec until the pressure of the entire weight is applied to the specimen. After 5 seconds, record the thickness as caliper in 0.01 mm increments.

[0130] The test fluid to be administered to the wet test specimen is prepared by adding 100.0 grams of sodium chloride (reagent grade, any convenient source) to 900 grams of deionized water in a 1-liter Erlenmeyer flask. Stir until the sodium chloride is completely dissolved.

[0131] Two hours prior to the test, absorbent article samples are conditioned at 23°C ± 3°C and 50% ± 2% relative humidity. Dry test specimens are taken from an area of ​​the sample free of seams, folds, or wrinkles, ideally from the center of the absorbent article (the intersection of the longitudinal and transverse centerlines). Dry test specimens are cut to a width of 50.8 mm along the CD (transverse direction, i.e., parallel to the transverse axis of the sample) and a length of 50.8 mm along the MD (parallel to the longitudinal axis of the sample), and prepared for MD (machine direction) bending by maintaining their orientation after cutting and marking the surface facing the body (or the surface intended to face the body in the finished product). Dry specimens are prepared for CD (machine direction) bending by cutting them to a width of 50.8 mm along MD (transverse direction, i.e., parallel to the transverse axis of the sample) and a length of 50.8 mm along CD (parallel to the longitudinal axis of the sample), maintaining their orientation after cutting, and marking the surface facing the body (or the surface intended to face the body of the finished product). The thickness of the specimen is measured as described herein and recorded as the dry specimen caliper in units of 0.01 mm. Next, the mass of the specimen is measured and recorded as the dry mass in units of 0.001 grams. Mass (g) is multiplied by the area (0.002581 m²). 2 The basis weight of the test specimen is calculated by dividing by ), and the dry basis weight of the test specimen is 0.01 g / m². 2 Record in units. Basis weight of the test specimen (g / m²) 2 The bulk density of the test specimen is calculated by dividing the given value by the thickness of the test specimen (mm), and then dividing the quotient by 1000, resulting in a dry specimen density of 0.01 g / cm³. 3 Record in units. Similarly, prepare five duplicate dried test specimens.

[0132] First, the wet specimen is prepared in exactly the same manner as the dry specimen, and then the test fluid is added immediately before testing as follows: First, the thickness and mass of the dry specimen are measured as described herein and recorded as the initial thickness in units of 0.01 mm and the initial mass in units of 0.001 g. Next, the dry specimen is completely immersed in the test fluid for 60 seconds. After 60 seconds, the specimen is removed from the test fluid and oriented vertically for 30 seconds to allow excess fluid to drip out. At this point, the thickness and mass of the wet specimen are measured as described herein and recorded as the wet specimen caliper in units of 0.01 mm and the wet specimen mass in units of 0.001 g. If desired, the mass of the test fluid in the specimen is calculated by subtracting the initial mass (g) from the wet specimen mass (g) and recorded as the specimen fluid volume in units of 0.001 g. The wet specimen must be tested within 10 minutes after being removed from the test fluid. Similarly, five duplicate wet specimens are prepared.

[0133] The universal test frame for the deflection bending test is programmed so that the upper fixture moves downward relative to the lower fixture at a speed of 1.0 mm / second until the upper bar touches the top surface of the test specimen with a minimum force of 0.02 N, and then the crosshead is moved so that this continues for a further 12 mm. The crosshead is then immediately returned to its original position at a speed of 1.0 mm / second. Force (N) and displacement (mm) data are collected continuously at 100 Hz throughout the test.

[0134] The dry specimen is loaded so that its sides are parallel to each bar, straddling the two lower bars, and its center is positioned below the upper bar. For MD bending, the MD direction of the specimen is perpendicular to the length of the three bars. The test is started, and force and displacement data are collected continuously.

[0135] Create a graph of force (N) versus displacement (mm). From the graph, determine the maximum peak force and record it as the dry MD peak load in units of 0.01 N. Then, calculate the maximum slope of the curve between the initial force and the maximum force (in the loaded portion of the curve) and record it in units of 0.1. Calculate the modulus of elasticity as follows and record it as the dry MD modulus of elasticity of 0.001 N / mm².2 Record in units. CD or MD dry or wet flexural modulus (N / mm²) 2 ) = (slope × (span) 3 )) / (4 × test piece width × (test piece caliper 3 ))

[0136] The bending stiffness was calculated as follows, and the dry MD bending stiffness was 0.1 Nmm. 2 Record in units. CD or MD dry or wet bending stiffness (Nmm) 2 ) = modulus of elasticity × moment of inertia In the formula, moment of inertia (mm 4 ) = (test piece width × (test piece caliper 3 )) / 12

[0137] Similarly, the procedure is repeated for all five duplicates of the dried specimen. The arithmetic mean of the five duplicate dried specimens is calculated for each parameter, and the dried specimen "caliper" is calculated in units of 0.01 mm, 0.01 g / m². 2 Unit of dry test piece basis weight 2 , 0.001 g / cm³ 3 Dry specimen density in units of 0.01 N, dry CD or MD peak load in units of 0.01 N / mm² 2 The dry CD or MD flexural modulus and Nmm in units of elasticity. 2 Report the bending stiffness in units of dry CD or MD.

[0138] Here, the entire procedure is repeated for all five replicas of the wet specimen, and the results are expressed as wet CD or MD peak load in units of 0.01 N, 0.001 N / mm². 2 Wet CD or MD flexural modulus in units, and Nmm 2 Report the wet CD or MD bending stiffness in units.

[0139] Wet and dry CD ultra-high sensitivity three-point bending method The CD (transverse) bending properties of the test samples are measured using a highly sensitive three-point bending test on a general-purpose constant-speed elongation test frame equipped with a load cell suitable for the force to be measured (preferred equipment is the MTS Alliance using TestSuite Software available from MTS Systems Corp. (Eden Prairie, MN), or equivalent). The tests are performed on both dry and wet specimens. The intention of this method is to simulate the deformation created in the xy plane by the wearer of absorbent material during normal use. All tests are performed in a controlled room at 23°C ± 3°C and 50% ± 2% relative humidity.

[0140] The ultra-high-sensitivity three-point bending method is designed to maximize the force signal-to-noise ratio when testing materials with very low bending forces. The force signal is maximized by using a highly sensitive load cell (e.g., 5N), a small span (load is proportional to the cube of the span), and a wide sample width (total measured load is directly proportional to the width). The fixture is designed so that the bending measurement is performed under tension, allowing the fixture mass to be kept to a minimum. Noise in the force signal is minimized by keeping the load cell stationary to reduce mechanical vibration and inertial effects, and by keeping the mass of the fixture attached to the load cell as small as possible.

[0141] Referring to Figures 11A to 11C, the load cell 1001 is mounted on the fixed crosshead of the universal test frame. The ultra-high sensitivity fixture 1000 consists of three thin blades constructed from a lightweight rigid material (such as aluminum or equivalent). Each blade has a thickness of 1.0 mm, a rounded edge, and a length capable of accommodating a bending width of 100 mm. Each blade has cavities 1004a and 1004b (outer blades) and 1005 (center blade) cut out along their horizontal edges to create a height h of 5 mm of blade material. The two outer blades 1003a and 1003b are mounted horizontally on the movable crosshead of the universal test frame, aligned parallel to each other, with their horizontal edges aligned vertically. The span S between the two outer blades 1003a and 1003b is 5 mm ± 0.1 mm (inner edge to inner edge). The central blade 1002 is mounted on a load cell on a fixed crosshead of the universal test frame. When in place, the central blade 1002 is parallel to the two outer blades 1003a and 1003b, with its center located midway between the outer blades 1003a and 1003b. The blade fixture includes a one-piece adapter suitable for fitting and securing the blade in place at each position on the universal test frame, so that the horizontal edge of the blade is perpendicular to the movement of the crossbeam of the universal test frame.

[0142] The test fluid to be administered to the wet test specimen is prepared by adding 100.0 grams of sodium chloride (reagent grade, any convenient source) to 900 grams of deionized water in a 1-liter Erlenmeyer flask. Stir until the sodium chloride is completely dissolved.

[0143] Two hours prior to the test, the sample is conditioned at 23°C ± 3°C and 50% ± 2% relative humidity. Dry specimens are taken from areas of the sample free of seams, folds, or wrinkles. The dry specimens are cut to a width of 50.0 mm along the CD (transverse direction, i.e., parallel to the transverse axis of the sample) and a length of 100.0 mm along the MD (machine direction, i.e., parallel to the longitudinal axis of the sample), and prepared for the CD bend (i.e., a bend perpendicular to the transverse axis of the sample) by maintaining their orientation after cutting and marking the surface facing the body (or the surface intended to face the body of the finished product). Five duplicate dry specimens are prepared in the same manner.

[0144] First, prepare the wet test specimen in exactly the same manner as the dry test specimen, and then add the test fluid immediately before testing as follows: Immerse the dry test specimen completely in the test fluid for 60 seconds. After 60 seconds, remove the test specimen from the test fluid and orient it vertically for 30 seconds to allow excess fluid to drip out. After removing the wet test specimen from the test fluid, it must be tested within 10 minutes. Similarly, prepare five duplicate wet test specimens.

[0145] The universal test frame is programmed so that the movable crosshead moves in the opposite direction to the fixed crosshead at a speed of 1.0 mm / second. The crosshead movement begins with the specimen 1006 flat and unbiased on the outer blades 1003a and 1003b, and continues with the inner horizontal edge of the cavity 1005 within the central blade 1002 in contact with the upper surface of the specimen 1006, followed by an additional 4 mm crosshead movement. The crosshead stops at 4 mm and then immediately returns to zero at a speed of 1.0 mm / second. Force (N) and displacement (mm) are collected throughout at 50 Hz.

[0146] Before placing specimen 1006, the outer blades 1003a and 1003b are moved toward the central blade 1002 until a clearance C of approximately 3 mm exists between the inner horizontal edges of cavities 1004a and 1004b within the outer blades 1003a and 1003b and the inner horizontal edge of cavity 1005 within the central blade 1002, and then pass through the central blade 1002 (see Figure 11C). Specimen 1006 is positioned within clearance C so as to straddle the inner horizontal edges of cavities 1004a and 1004b within the outer blades 1003a and 1003b, with the MD (short side) of the specimen perpendicular to the horizontal edge of the blade and the body-facing surface of the specimen facing upward. Sample 1006 is centered between the outer blades 1003a and 1003b. The outer blades 1003a and 1003b are slowly moved in the opposite direction to the fixed crosshead until the inner horizontal edge of the cavity 1005 within the central blade 1002 contacts the upper surface of the test specimen 1006. The test is started, and force and displacement data are collected continuously.

[0147] Plot the force (N) against the displacement (mm). Record the maximum peak force in units of 0.001N. Calculate the area under the curve from the start of the load to the maximum peak force and use it as the bending energy, which is 0.001N. * Record in millimeters. The recovery energy is calculated as the area under the curve where the force is removed from the maximum peak down to 0.0 N, and is 0.001 N. * The recovery energy is recorded in millimeters. Similarly, the entire test procedure is repeated for a total of five dry specimens and five wet specimens.

[0148] For each specimen type (dry and wet), the arithmetic mean of the maximum peak force between similar specimens is calculated in units of 0.001 N and recorded as the dry peak load and wet peak load, respectively. For each specimen type (dry and wet), the arithmetic mean of the bending energy between similar specimens is calculated in units of 0.001 N. * The calculations are performed in millimeters and reported as dry bending energy and wet bending energy, respectively. For each specimen type (dry and wet), the arithmetic mean of the recovery energy between similar specimens is calculated as 0.001 N.* The calculations are performed in millimeters and reported as dry recovery energy and wet recovery energy, respectively.

[0149] Wet and dry cluster compression methods The cluster compression test measures the force-versus-displacement behavior of intentionally "clustered" absorbent article test samples over five cycles of load application ("compression") and load removal ("recovery") using a general-purpose constant-speed elongation test frame (preferred equipment is MTS Alliance using TestSuite software available from MTS Systems Corp. (Eden Prairie, MN), or equivalent) equipped with load cells where the measured force is within 1% to 99% of the cell's limit. This test is performed on dry specimens as well as wet specimens administered with a specific amount of test fluid. The intent of this method is to simulate the deformation that occurs in the z-plane of the crotch area or its components of an absorbent article when worn by a wearer during a sit-to-stand motion. All tests are performed in a room controlled at 23°C ± 3°C and 50% ± 2% relative humidity.

[0150] Figures 12 to 13B show the test apparatus. The bottom stationary fixture 3000 consists of two matching sample clamps 3001, each 100 mm wide, mounted on their respective movable platforms 3002a and 3002b. The clamps have a 110 mm long "knife edge" 3009 that grips a 1 mm thick hard rubber surface 3008. When closed, the clamps are flush with the inside of their respective platforms. The clamps are aligned to hold an unbunched specimen horizontally and perpendicularly to the tensile axis of the tensile testing machine. These platforms are mounted on rails 3003, which allow the platforms to be moved horizontally from side to side and locked in place. The rails have adapters 3004 that fit into the mounts of the tensile testing machine, allowing the platforms to be fixed horizontally and perpendicularly to the tensile axis of the tensile testing machine. The upper fixture 2000 is a cylindrical plunger 2001 with a total length of 70 mm and a diameter of 25.0 mm. The contact surface 2002 is flat and not curved. The plunger 2001 has an adapter 2003 that fits into the load cell mount, which allows the plunger to be fixed perpendicular to the tensile axis of the tensile testing machine.

[0151] At least two hours before the test, prepare the test sample at 23°C ± 3°C and 50% ± 2% relative humidity. Prepare the test specimen as follows: When testing an untouched absorbent article, remove any release paper from any panty fastening adhesive on the clothing-facing side of the article, if present. Lightly coat the adhesive with talc powder to reduce stickiness. If there is a cuff, cut it off with scissors, taking care not to disturb the top sheet or any other underlayers of the article. Place the article on a bench with the body-facing surface facing upwards. Mark the intersection of the longitudinal and transverse centerlines on the article. Using a rectangular cutting die or equivalent cutting means, cut the test specimen 100 mm longitudinally and 80 mm transversely, centered at the intersection of the centerlines. When testing a material layer or layered component of an absorbent article, place the material layer or component on a bench and orient it as it would be incorporated into the finished product (i.e., identify the surface facing the body, the transverse axis, and the longitudinal axis). Using a rectangular cutting die or equivalent cutting means, cut the test specimen into 100 mm longitudinal and 80 mm transverse sections, centered at the intersection of the centerlines. Measure the mass of the test specimen and record it in units of 0.001 g. Convert the mass (g) to the area (0.008 m²). 2 The basis weight of the test specimen is calculated by dividing by ), and the basis weight is 1 g / m². 2 Record in units.

[0152] The test specimens can be analyzed in both wet and dry conditions. No further preparation is required for dry specimens. The test fluid to be administered to the wet specimens is prepared by adding 100.0 grams of sodium chloride (reagent grade, any convenient source) to 900 grams of deionized water in a 1-liter Erlenmeyer flask. Stir until the sodium chloride is completely dissolved. A total of 7 mL of the test solution is administered to the wet specimens, as detailed below.

[0153] The liquid dose is added using a graduated Eppendorf pipette, spreading the fluid over the entire surface of the specimen facing the body within approximately 3 seconds. The wetted specimen is tested for 10.0 minutes ± 0.1 minutes after the application of the dose.

[0154] The tensile testing machine is programmed to zero the load cell, then the upper device is lowered at 2.00 mm / second until the plunger's contact surface touches the specimen and the load cell reading is 0.02 N. The crosshead is then zeroed. The system is programmed to lower the crosshead by 15.00 mm at a speed of 2.00 mm / second, and immediately raise it by 15.00 mm at a speed of 2.00 mm / second. This cycle is repeated for a total of 5 cycles without delay between cycles. Data is collected at 50 Hz during all compression / decompression cycles.

[0155] Position the left platform 3002a 2.5 mm from the side of the upper plunger (distance 3005). Fix the position of the left platform. This platform 3002a remains stationary during the experiment. Align the right platform 3002b 50.0 mm from the stationary clamp (distance 3006). Raise the upper probe 2001 so that it does not interfere with the loading of the specimen. Open both clamps 3001. Referring to Figure 13A, position the dry specimen so that its longitudinal edge (i.e., the 100 mm long edge) is within the clamp. Align the lateral center of the dry specimen and firmly secure both edges within the clamp. Referring to Figure 13B, move the right platform 3002b 20 mm toward the stationary platform 3002a so that a 30.0 mm separation is achieved between the left and right clamps. When the movable platform is positioned, ensure that the dry specimen is bent upward. Here, manually lower probe 2001 until its lower surface is approximately 1 cm above the upper surface of the curved specimen.

[0156] The test is initiated, and force (N) and displacement (mm) data are continuously collected over all five cycles. A force (N) versus displacement (mm) graph is created individually for each cycle. A representative curve is shown in Figure 14A. From the curves, the maximum dry compressive force for each cycle is determined in units of 0.01 N, then multiplied by 101.97, and recorded in units of 1 wt gram. The dry recovery % between the first and second cycles is calculated as (TD-E2) / (TD-E1)×100 (where TD is the total displacement and E2 is the extension in the second compression curve exceeding 0.02 N), and recorded in units of 0.01%. In the same manner, the dry recovery rate % between the first cycle and the other cycles is calculated as (TD-E1) / (TD-E1)×100, and recorded in units of 0.01%. Referring to Figure 14B, the dry compressive energy for cycle 1 is calculated as the area under the compression curve (i.e., area A+B), and is 0.1 N. * Record in millimeters. Calculate the dry energy loss from cycle 1 as the area between the compression curve and the decompression curve (i.e., area A), and set it to 0.1 N. * Record in millimeters. Calculate the drying recovery energy of cycle 1 as the area under the decompression curve (i.e., area B), and set it to 0.1 N. * Report in millimeters. Similarly, for each of the other cycles, report the dry compression energy (N). * (mm), drying energy loss (N) * mm), and drying recovery energy (N * Calculate mm) and 0.1N * Record in millimeters. Similarly, analyze a total of five duplicate dried specimens and report the arithmetic mean among the five dried specimens for each of the aforementioned parameters, including basis weight.

[0157] Here, the entire procedure is repeated for a total of five replicated wet test specimens, with the maximum wet compressive force in 1-gram units for each cycle and 0.1 N for each cycle. * Wet compression energy in millimeter units, 0.1N for each cycle. * Wet energy loss in millimeters, 0.1N per cycle *The results for each of the five cycles are reported as the arithmetic mean of five wet replications for the wet recovery energy in millimeters and the wet recovery percentage for each cycle. Of particular importance are the wet recovery energy and wet recovery percentage characteristics of the fifth cycle from this test method.

[0158] CD periodic stretching up to 3% distortion The periodic tensile and recovery responses of absorbent material specimens are measured over 10 cycles of load application ("extension") and load removal ("recovery") using a general-purpose constant-speed elongation test frame. The specimen is repeated 10 times up to 3% engineering strain, and then returned to zero engineering strain. For each cycle, stiffness, peak load, normalized peak energy, normalized recovery energy, strain at the start of the cycle, and strain at the end of the cycle (i.e., "permanent strain") are calculated and reported. The intent of this method is to understand the ability of a sample to be stretched in the xy plane as a result of a force on the body and then to recover to their original state. All measurements are performed in a laboratory maintained at 23°C ± 2°C and 50% ± 2% relative humidity, and the specimens are conditioned in this environment for at least 2 hours prior to testing.

[0159] A suitable general-purpose constant-speed elongation test frame is an MTS Alliance or equivalent interfaced to a computer running TestSuite control software (available from MTS Systems Corp, Eden Prairie, MN). The universal test frame is equipped with load cells in which the force to be measured is within 1% to 99% of the cell's limit. The fixtures used to grip the test specimen are lightweight (less than 80 grams) vise-acting clamps with knife or serrated edge gripping surfaces of at least 40 mm width. The fixtures are mounted on the universal test frame and positioned horizontally and vertically relative to each other.

[0160] The test specimens are prepared as follows: Test material is obtained by cutting from the absorbent article, if necessary. When cutting the test material, care is taken not to contaminate or deform the material layer during the process. The test specimen is cut from an area of ​​the test material that does not have any folds or wrinkles remaining. The test specimen is approximately the same length as the transverse length of the article (parallel to the transverse axis of the article, or the intended transverse axis of the article). When cutting test specimens from absorbent articles of different sizes and widths, the total length of the test specimen (L) total ) may vary from product to product, and therefore the results are normalized to compensate for this variation. The test specimen has a width of 25.4 mm (parallel to the longitudinal axis of the article or the intended longitudinal axis). Test specimen width (w) = 25.4 mm. Total test specimen length (L total Measure the distance and record it in 0.1 mm increments. Prepare five duplicate specimens in the same manner.

[0161] The thickness (t) of the specimen is measured using a manual micrometer equipped with a clamp capable of applying a steady pressure of 0.1 psi ± 0.01 psi. The manual micrometer is a self-weight instrument with accurate readings to 0.01 mm. A suitable instrument is the Mitutoyo Series 543 ID-C Digimatic, available from VWR International, or an equivalent. The clamp is a circular, movable surface with a flat surface and a diameter of 25.4 mm or less. The specimen is supported by a horizontal, flat reference platform that is larger than the surface of the clamp and parallel to the surface of the clamp. Zero the micrometer relative to the horizontal, flat reference platform. Place the specimen on the platform and center it under the clamp. Lower the clamp by hand at a descent rate of 3 ± 1 mm / sec until the pressure of the entire weight is applied to the specimen. After 5 seconds, record the thickness as the specimen thickness (t) in units of 0.01 mm.

[0162] Prepare the universal test frame as follows: Set the initial grip separation distance to a nominal gauge length (L) that is shorter than the total length of the test specimen. nominal Set to (i.e., L) so that the test specimen can be securely gripped at both ends. nominal<L total )。 Then, set the crosshead to zero. To ensure that there is no pre-tension in the test specimen at the start of the test, program the test frame to move the grips towards each other by an intentional slack of 1 mm. (During this movement, the test piece slackens between the tensile grips.) Next, the grips move apart at a slackening speed of 1 mm / sec until they exceed a slackening preload of 0.05 N. At this time, the following occurs. 1) Define the crosshead position signal (mm) as the slackening of the test piece (L slack ). 2) Calculate the initial test piece gauge length (L0) as the nominal gauge length + slackening L0 = L nominal +L slack , where the unit is millimeters. 3) Set the crosshead elongation (ΔL) to zero (0.0 mm). 4) Set the crosshead displacement (mm) to zero (0.0 mm). At this position, the engineering strain is zero, i.e., 0.0. Engineering strain is calculated as the change in length (ΔL) divided by the initial length (L0). Engineering strain = ΔL / L0. For one test cycle, the grips move apart at an initial speed of 1 mm / sec until they exceed an engineering strain end point of 0.03 mm / mm, and immediately thereafter, the grips move towards each other at an initial speed of 1 mm / sec until the crosshead signal is less than the crosshead return position of 0 mm. The test cycle is repeated until a total of 10 cycles are completed.

[0163] The test is performed by inserting the test piece into the grips such that the long axis of the test piece is parallel to the movement of the crosshead and centered on that movement. Start the test and continuously collect time, force, and displacement data at a data collection rate of 100 Hz.

[0164] Create a graph of load (N) vs. displacement individually for all 10 cycles. For each cycle, perform the following. Record the peak load in units of 0.01 N. Calculate the peak energy (E peak ) as the area under the load vs. displacement curve from the start of the cycle to the strain end point of 0.03 mm / mm (during the load portion of the cycle), and 0.01 N *Record in mm units. Calculate the return energy as the area under the load-displacement curve from the strain end point of 0.03 mm / mm to the crosshead return of 0 mm (during the unloading part of the cycle), and 0.01 N * Record as the recovery energy in mm units. As the peak energy divided by the initial length, calculate the normalized peak energy (NE peak ), and record in units of 0.01 mN (NE peak = E peak / L0). Calculate the normalized return energy (NE return ) as the return energy divided by the initial length (NE return = E return / L0), and record in units of 0.01 mN. The units of NE peak and NE return are millinewtons (mN).

[0165] Here, create a graph of engineering stress (σ) vs. engineering strain for all 10 cycles, and perform the following for each cycle. The engineering stress in units of N / mm 2 is the load divided by the cross-sectional area of the test piece, and the cross-sectional area is the product of the width (w) and thickness (t) of the test piece (σ = load / (w × t)). For the line between the point where the minimum force occurs and the point where the maximum force occurs (during the loading part of the cycle), determine the elastic modulus, or the slope of the stress-strain curve, and record in units of 0.01 N / mm as the elastic modulus. Calculate the stiffness by multiplying the elastic modulus by the thickness of the test piece, and record in units of 0.01 N / mm as the tensile stiffness. Define the strain of the test piece at the start of the cycle by the strain when the 0.05 N relaxation preload is exceeded for that cycle (during the loading part of the cycle), and record in units of 0.01 mm / mm as the initial cycle strain. Define the strain of the test piece at the end of the cycle by the strain when the load becomes less than the 0.05 N preload for that cycle (during the unloading part of the cycle), and record in units of 0.01 mm / mm as the permanent strain. Similarly, repeat the entire procedure for all 5 replicates.

[0166] The arithmetic mean of five replicated specimens is calculated for each of the 10 cycles and for each parameter, and reported as peak load in 0.01 N units, normalized peak energy in 0.01 mN units, normalized recovery energy in 0.01 mN units, tensile stiffness in 0.01 N / mm units, cycle initial strain in 0.01 mm / mm units, and permanent strain in 0.01 mm / mm units.

[0167] Method for measuring the spacing and area of ​​structural joint site patterns The spacing between inconspicuous structural joints used to create a quilt-like pattern on an absorbent material sample, and the total area occupied by these elements in a specific region of the sample, are measured on an image of the absorbent material sample acquired using a flatbed scanner. The scanner can scan in reflectance mode at a resolution of 2400 dpi and 8-bit grayscale. A suitable scanner is the Epson Perfection V750 Pro from Epson America Inc. (Long Beach, CA, USA) or an equivalent. The scanner is connected to a computer running an image analysis program. A suitable program is ImageJ v.1.52 (National Institute of Health, USA) or an equivalent. The sample image is distance-calibrated against an acquired NIST-certified ruler image. To allow for maximum contrast, the test specimen is backed with a uniformly colored opaque black background before image acquisition. All tests are performed in a humidified room maintained at approximately 23±2°C and approximately 50±2% relative humidity.

[0168] Test samples are prepared as follows: Remove the absorbent article from its existing packaging. If the article is folded, gently unfold it and smooth out all wrinkles. If wings are present, stretch them out, but leave the release paper intact. Prior to testing, the test samples are conditioned for 2 hours at approximately 23°C ± 2°C and a relative humidity of approximately 50% ± 2%.

[0169] The image is obtained as follows: The ruler is placed on the scanner bed so that it is oriented parallel to the side of the scanner glass. The image of the ruler (calibration image) is acquired in reflective mode at a resolution of 2400 dpi (approximately 94 pixels / mm) and 8-bit grayscale. The calibration image is saved as an uncompressed TIFF format file. After acquiring the calibration image, the ruler is removed from the scanner glass and the test sample is scanned under the same scanning conditions as follows: The test sample is placed in the center of the scanner glass and, if necessary, secured so that the body-facing surface of the sample is flat against the scanner's glass surface. The sample is oriented so that the entire sample is within the glass surface. A black background is placed over the test piece, the scanner lid is closed, and a scan image of the entire sample is acquired using the same settings as used for the calibration image. The sample image is saved as an uncompressed TIFF format file.

[0170] The sample image is analyzed as follows: The calibration image file is opened in the image analysis program, and the image resolution is calibrated using an embossed ruler to determine the number of pixels per millimeter. Next, the sample image is opened in the image analysis program, and the distance scale is set using the image resolution determined from the calibration image. Then, the pattern of embossed elements present on the sample in the image is visually inspected, and the zones of the pattern to be analyzed are identified. For example, an absorbent article can be divided into three equally lengthed zones in the machine direction, such as Zone 1, which is the front 1 / 3 zone; Zone 2, which is the middle 1 / 3 zone; and Zone 3, which is the edge 1 / 3 zone. Using the image analysis tool, the shape is drawn along the perimeter of the first inconspicuous zone to be analyzed. The area of ​​this first zone is measured, and the total area of ​​Zone 1 is 0.01 mm². 2 Record in units of 0.01 mm. Here, measure the area of ​​individual inconspicuous embossed elements located inside the perimeter of Zone 1 as follows: Draw the smallest possible boundary circle around each embossed element so that no part of the embossed element lies outside the boundary circle. Next, measure the area of ​​the boundary circle of that embossed element and record the embossed element area as 0.01 mm. 2Record in units of 0.01 mm. Similarly, measure the area of ​​each embossed element, including the portion of the embossed element located within Zone 1, and record each in units of 0.01 mm. 2 Record in units. Here, the areas of all embossed elements in Zone 1 are summed up, and the total embossed element area of ​​Zone 1 is 0.01 mm². 2 Record in units of 0.01 mm. Divide the total embossed element area of ​​Zone 1 by the total area of ​​Zone 1, then multiply by 100 and record as the percentage of the total area of ​​Zone 1 represented by the embossed elements. Measure the spacing between each inconspicuous embossed element inside Zone 1 as follows: Measure the distance from the center of the minimum boundary circle drawn around an inconspicuous embossed element inside Zone 1 to the center of the minimum boundary circle drawn around the nearest adjacent inconspicuous embossed element inside Zone 1, as described herein, and record this distance as the embossed spacing in units of 0.01 mm. Repeat this process for all adjacent embossed elements inside Zone 1, recording each distance in units of 0.01 mm. Next, calculate the arithmetic mean of all measured embossed spacings between the nearest adjacent elements inside Zone 1 and record it as the Zone 1 embossed spacing in units of 0.01 mm.

[0171] Similarly, the entire procedure is repeated for each additional zone containing embossed elements present on the test sample, and these zones are labeled accordingly as Zone 2, Zone 3, etc.

[0172] Light touch re-wetting method The light-touch re-wetting method quantitatively measures the mass of liquid that emerges from a test sample of an absorbent article that has been administered a specific amount of artificial menstrual fluid (AMF) (as described herein) when weight is applied over a specific length of time. All measurements are performed in a laboratory maintained at 23°C ± 2°C and 50% ± 2% relative humidity.

[0173] The test sample is administered using a syringe pump equipped with a disposable syringe. A suitable pump is Perfusor® Compact S (available from B. Braun) or equivalent, and must be capable of accurately dispensing AMF at a rate of 42 mL / min. The disposable syringe is of sufficient capacity (e.g., BD Plastipak 20 mL) and is connected to a flexible tube with a 3 / 16 inch bore (e.g., Original Perfusor® Line, available from Braun, or equivalent). The AMF is prepared as described herein and brought to room temperature (23°C ± 2°C) before use in this test. Before starting the measurement, the syringe is filled with AMF, the flexible tube is primed with the liquid, and the dispensing rate (42 mL / min) and administration volume (4.0 mL ± 0.05 mL) are verified according to the manufacturer's instructions. Next, the flexible tube is attached so that it is oriented perpendicularly to the test sample and the distance between the tip of the tube and the surface of the test sample is 19 mm. Notably, the AMF must be withdrawn from the syringe every 15 minutes and thoroughly mixed.

[0174] The re-wetting weight assembly consists of an acrylic plate and stainless steel weights. The acrylic plate has dimensions of 65mm x 80mm and a thickness of approximately 5mm. Together with the acrylic plate, the stainless steel weights have a total mass of 2 pounds (907.19g) and apply a pressure of 0.25 psi below the surface of the acrylic plate.

[0175] For each test sample, five sheets of 4-inch x 4-inch filter paper are used as the re-wetted substrate. Before testing, the filter paper is conditioned at 23°C ± 2°C and 50% ± 2% relative humidity for at least 2 hours. Suitable filter paper has a basis weight of approximately 139 gsm, a thickness of approximately 700 microns, and an absorption rate of approximately 1.7 seconds, and is available from Ahlstrom-Munksjo North America LLC (Alpharetta, GA) and VWR International as Ahlstrom Grade 989 or equivalent.

[0176] Prepare the test samples as follows: Before testing, the test samples are conditioned at 23±2°C and 50%±2% relative humidity for at least 2 hours. Remove the test samples from all packaging, taking care not to press down on or pull the product during handling. Place the test samples horizontally on a hard, flat surface and gently straighten any folds. Determine the test positions as follows: For symmetrical samples (i.e., the front side of the sample is the same shape and size as the rear side of the sample when divided laterally along the midpoint of the longitudinal axis of the sample), the test position is the intersection of the midpoint of the longitudinal axis of the sample and the midpoint of the transverse axis. For asymmetrical samples (i.e., the front side of the sample is not the same shape and size as the rear side of the sample when divided laterally along the midpoint of the longitudinal axis of the sample), the test position is the intersection of the midpoint of the longitudinal axis of the sample and the transverse axis located at the midpoint of the wing of the sample. Prepare a total of three test samples.

[0177] Place the test sample horizontally on a flat, hard surface, and position the previously identified test location directly below the tip of the flexible tube. Adjust the height of the tube so that it is 19.0 mm above the surface of the test sample. Start the pump and dispense 4.0 mL ± 0.05 mL of AMF at a rate of 42 mL / min. As soon as the AMF is completely dispensed, start a 10-minute timer. At this point, obtain the mass of five sheets of filter paper and record it as the dry mass to the nearest 0.001 gram. After 10 minutes, place the five pre-baked sheets of filter paper on the test sample, centering the stack above the dispensing location. Next, place the acrylic plate in the center of the top of the filter paper so that its long side is parallel to the longitudinal axis of the test sample. Then, carefully lower the stainless steel weight into the center of the acrylic plate and immediately start a 30-second timer. After 30 seconds, gently remove the re-wet weight and acrylic plate and set them aside. Obtain the mass of five filter papers and record the wet mass in units of 0.001 grams. Subtract the dry mass from the wet mass of the filter paper and record the re-wet mass in units of 0.001 grams. Before testing the next sample, wipe off any remaining test liquid from the bottom of the acrylic plate. Repeat the same procedure for a total of three duplicate test samples.

[0178] The arithmetic mean of re-wetting between three replication test samples is calculated and reported as "light touch re-wetting" in units of 0.001 g.

[0179] Preparation of Artificial Menstrual Fluid (AMF) Artificial menstrual fluid (AMF) is composed of a mixture of defibrous sheep blood, phosphate-buffered saline, and mucus components. AMF is prepared to have a viscosity of 7.15–8.65 centistokes at 23°C.

[0180] The viscosity of AMF is measured using a low-viscosity rotational viscometer (a suitable instrument is a Cannon LV-2020 Rotary Viscometer with a UL adapter (Cannon Instrument Co. (State College, PA)) or equivalent). A spindle of the appropriate size for the viscosity range is selected, and the instrument is operated and calibrated according to the manufacturer's specifications. Measurements are taken at 23°C ± 1°C and 60 rpm. Results are reported in 0.01 centistokes units.

[0181] Reagents required for AMF preparation include defibrotic sheep blood with a hematocrit value of 38% or higher (collected under sterile conditions, available from Cleveland Scientific, Inc. (Bath, OH) or equivalent), gastric viscous (crude form, sterile, available from American Laboratories, Inc. (Omaha, NE) or equivalent) with a target viscosity of 3-4 centistokes when prepared as a 2% aqueous solution, 10 v / v% lactic acid aqueous solution, 10 w / v% potassium hydroxide aqueous solution, dibasic anhydrous sodium phosphate (reagent grade), sodium chloride (reagent grade), monobasic monohydrate sodium phosphate (reagent grade), and distilled water (each available from VWR International or equivalent sources).

[0182] Phosphate-buffered saline consists of two individually prepared solutions (Solution A and Solution B). To prepare 1 L of Solution A, add 1.38 ± 0.005 g of monobasic sodium phosphate monohydrate and 8.50 ± 0.005 g of sodium chloride to a 1000 mL volumetric flask and add distilled water to the container volume. Mix thoroughly. To prepare 1 L of Solution B, add 1.42 ± 0.005 g of dibasic anhydrous sodium phosphate and 8.50 ± 0.005 g of sodium chloride to a 1000 mL volumetric flask and add distilled water to the container volume. Mix thoroughly. To prepare phosphate-buffered saline, add 450 ± 10 mL of Solution B to a 1000 mL beaker and stir slowly on a stirring plate. Insert a calibrated pH probe (accuracy to 0.1) into the beaker of solution B, and while stirring, add a sufficient amount of solution A to adjust the pH to 7.2 ± 0.1.

[0183] The mucus component is a mixture of phosphate-buffered saline, potassium hydroxide aqueous solution, gastric viscous, and lactic acid aqueous solution. The amount of gastric viscous added to the mucus component directly affects the final viscosity of the prepared AMF. To determine the amount of gastric viscous required to obtain AMF within the target viscosity range (7.15–8.65 centistokes at 23°C), three batches of AMF with varying amounts of gastric viscous in the mucus component are prepared, and then a linear fit is performed using the least-squares method through the three points to interpolate the exact required amount from the concentration-viscosity curve. The appropriate range for gastric viscous is usually 38–50 grams.

[0184] To prepare approximately 500 mL of mucus component, add 460 ± 10 mL of pre-prepared phosphate-buffered physiological water and 7.5 ± 0.5 mL of 10 w / v% potassium hydroxide aqueous solution to a 1000 mL sturdy glass beaker. Place this beaker on a stirring hot plate and heat it to 45°C ± 5°C while stirring. Basis the specified amount of gastric viscous (±0.50 g) and slowly sprinkle it into the pre-prepared liquid at 45°C to prevent condensation. Cover the beaker and continue mixing. Maintain the temperature of this mixture above 50°C but not above 80°C for 15 minutes. Continue heating for 2.5 hours while gently stirring, maintaining this temperature range. After 2.5 hours, remove the beaker from the hot plate and allow it to cool to below 40°C. Next, add 1.8 ± 0.2 mL of 10 v / v% lactic acid aqueous solution and mix thoroughly. Autoclave the mucilage mixture at 121°C for 15 minutes, then allow to cool for 5 minutes. Remove the mucilage mixture from the autoclave and stir until the temperature reaches 23°C ± 1°C.

[0185] Adjust the temperature of the sheep blood and mucus components to 23°C ± 1°C. Using a 500 mL graduated cylinder, measure the total volume of the pre-prepared mucus component batch and add this volume to a 1200 mL beaker. Add an equal volume of sheep blood to the beaker and mix thoroughly. Using the viscosity method described above, confirm that the viscosity of the AMF is 7.15–8.65 centistokes. If not, discard the batch and prepare another batch by adjusting the mucus components as needed.

[0186] Certified AMF must be refrigerated at 4°C unless intended for immediate use. AMF can be stored in an airtight container at 4°C for up to 48 hours after preparation. Before testing, AMF must be at 23°C ± 1°C. Any unused portion is discarded after testing is complete.

[0187] Measurement of flexible coupling channels The length of the flexible bonding embossing in the flexible bonding channel region formed near the central portion of the absorbent article test sample, the length of the flexible bonding land region between two adjacent flexible bonding embossings, the flexible bonding channel width, and the flexible bonding channel depth are measured using optical profilometry to obtain an area surface topography of the body-facing side of the test sample. The length of the flexible bonding embossing, the length of the flexible bonding land region between two adjacent embossings, and the flexible bonding channel width of the flexible bonding channel are measured at the base of the recess, and the depth of the flexible bonding channel is measured relative to the adjacent non-channel region. In addition, the rigidity-flexibility properties of the prepared test specimen in the flexible bonding channel region are measured using a general-purpose constant-rate elongation test frame. All tests are conducted in a room conditioned at 23°C ± 3°C and 50% ± 2% relative humidity, and the test specimens are conditioned in this environment for at least 2 hours prior to testing.

[0188] For determining the length of the flexible bond embossing, the length of the land region between flexible bond embossings, the channel width, and the channel depth, a three-dimensional (3D) surface topography image of the body-facing side of the test sample is recorded using an optical 3D surface topography measurement system. A suitable optical 3D surface topography measurement system is the MikroCAD Premium instrument, commercially available from LMI Technologies Inc. (Vancouver, Canada), or an equivalent. This system includes the following main components: a) a Digital Light Processing (DLP) projection device with directly digitally controlled micromirrors, b) a CCD camera with a resolution of at least 1600 × 1200 pixels, c) a projection optical system suitable for a measurement area of ​​at least 140 mm × 105 mm, d) a recording optical system suitable for a measurement area of ​​140 mm × 105 mm, e) a tripod base based on a small hard stone plate, f) a blue LED light source, g) a measurement, control, and evaluation computer running surface texture analysis software (preferred software is MikroCAD software with MountainsMap® technology, or an equivalent), and h) calibration plates for lateral (XY) and vertical (Z) calibration, available from the supplier. The optical 3D surface topography measurement system measures the surface height of a specimen using a digital micromirror pattern fringe projection technique. The measurement result is a 3D image of the surface height (defined as the Z axis) against displacement in the horizontal (XY) plane. This system has a field of view of 140 × 10⁵ mm with an XY pixel resolution of approximately 85 micrometers. The height resolution is set to 0.5 microns / count, and the height range is ±10 mm. Before testing, the instrument is calibrated according to the manufacturer's specifications using lateral (XY plane) and vertical (Z axis) calibration plates available from the vendor.

[0189] For surface topography measurements and subsequent channel MD stiffness measurements, test samples of absorbent articles are prepared as follows: The absorbent article is unfolded as necessary, but the protective cover that covers the panty-fastening adhesive (i.e., packaging paper or release paper) is kept in place. The front and back of the article are identified and labeled. In addition, the left and right sides of the article are identified and labeled relative to the left and right sides of the wearer. If the article is pre-folded, scissors or an equivalent sharp cutting device are used to cut along the width of the article, approximately 1 cm inward and parallel to the front fold, and any remaining folded or folded material from the front portion of the article is removed and discarded. Similarly, along the width of the article, approximately 1 cm inward and parallel to the rear fold, a cut is made to remove and discard any remaining folded or folded material from the rear portion of the article. After cutting, the remaining central portion of the absorbent article is retained as a test sample with a length of approximately 60 mm but at least 40 mm. With any residue from the folded material removed, the test sample is placed flat against a horizontally rigid surface. Next, the protective cover is removed from the panty-fixing adhesive, and talc powder is lightly sprinkled on the adhesive to reduce its stickiness. A total of five duplicate test samples are prepared in the same manner.

[0190] 3D surface topography images of the test sample are acquired as follows: The test sample is placed on a MikroCAD (or equivalent) table below the camera. The test sample is oriented so that the longitudinal axes of the left and right flexible coupling channel regions are perpendicular to the long axis (X-axis) of the instrument's field of view. 3D surface topography images of the test sample are collected according to the measurement procedure recommended by the instrument manufacturer, which may include focusing the measurement system and adjusting the brightness. No pre-filtering options are used. The collected height image files are stored on an evaluation computer running surface texture analysis software.

[0191] Open the 3D surface topography image in surface texture analysis software. Then, perform the following filtering steps on the image: 1) remove unwanted points, 2) apply a 3x3 pixel median filter to remove noise, and 3) apply a 3x3 pixel average filter to smooth the surface.

[0192] Flexible bond embossing length method: To measure the length "L" of the flexible bond embossing, a two-dimensional (2D) line profile (a subsample of the 3D surface image) is extracted from a position within one of the individual recessed regions within the flexible bond channel region perpendicular to the short side of the recess (i.e., the line crosses the longitudinal axis of the recess). This line profile extends along its central longitudinal axis over the entire length of the individual channel recess and includes the non-recessed regions directly adjacent to both ends of the channel. Those skilled in the art will know that if the resulting line profile does not generally represent the overall contour of the flexible bond channel region due to measurement noise or the presence of localized wrinkles or malformed channels (i.e., channels with a depth of less than 1 mm as determined by the flexible bond channel depth method described herein), then another test position in a separate recessed region of the flexible bond channel should be measured so as not to contain such artifacts. Here, a line height profile (height (mm) versus line length (mm)) is created. For example, as shown in Figure 15, it will be apparent to those skilled in the art that the flexible bonding channel region (minimum Z value) and the channel-free region (maximum Z value adjacent to the channel) are located on the height profile. This line profile shows the exemplary length of the recessed region within the flexible bonding channel. Determine the minimum height value (y-axis) on the line profile. Next, move along the left line of the profile in the z direction (y-axis) from the minimum height value to a position 100 microns away from the minimum height value and set a "left" marker on the line profile. Similarly, move along the right line of the profile in the z direction (y-axis) from the minimum height value to a position 100 microns away from the minimum height value and set a "right" marker on the line profile. Measure the horizontal x-distance between the left and right markers placed on the line profile and record it in units of 0.1 mm as the flexible bonding channel length. Now, repeat the entire procedure until a total of five distinct individual recessed regions of the flexible bonding channel have been analyzed on the test sample. Similarly, measure the five distinct individual recessed regions of the flexible binding channels in the remaining four replication test samples.Next, the arithmetic mean of all the flexible bond channel length values ​​recorded across all five test sample replicas is calculated and reported as the flexible bond embossing length "L" in units of 0.1 mm.

[0193] Five replicated test samples are retained and used for subsequent measurements of the flexible bond land region length.

[0194] Flexible bond land area length method. To measure the length of the land region "S" between two individual adjacent recessed regions (embossments) within a flexible bonded channel, a two-dimensional (2D) line profile (a subsample of a 3D surface image) is extracted as follows: This line profile includes the entire length of the two individual adjacent channel recesses along their central longitudinal axis, and further includes the non-recessed regions directly adjacent to both the leading edge of the first recessed region and the trailing edge of the second adjacent recessed region. Those skilled in the art will know that if the resulting line profile does not generally represent the overall contour of the flexible bonded channel region due to measurement noise or the presence of localized wrinkles or malformed channels (i.e., channels with a depth of less than 1 mm as determined by the flexible bonded channel depth method described herein), another test location including a different set of two adjacent recessed regions of the flexible bonded channel should be measured so as not to be present. Here, a line height profile (height (mm) versus line length (mm)) is created. For example, as shown in Figure 15, it will be apparent to those skilled in the art that the flexible bond channel region (minimum Z value) and the channel-free region (maximum Z value adjacent to the channel) are located on the height profile. This line profile shows the exemplary lengths of two adjacent recessed regions within the flexible bond channel and the distance between them. The distance between adjacent recessed regions is measured from the rear end of the first recessed region to the front end of the second recessed region, as follows: Determine the first minimum height value (y-axis) on the line profile within the first recessed region. Then, move along the line profile in the z direction to the right of the first minimum height value (y-axis) to a position 100 microns away from the first minimum height value and set the “first” marker on the line profile. Next, determine the second minimum height value (y-axis) on the line profile within the second recessed region. Move along the line profile in the z direction to the left of the second minimum height value (y-axis) to a position 100 microns away from the second minimum height value and set the “second” marker on the line profile. Next, the horizontal x-distance between the first and second markers placed on the line profile is measured and recorded in units of 0.1 mm as the length "S" of the flexible bond land region.The entire procedure is then repeated until a total of five distinct sets of adjacent pairs of recessed regions of flexible binding channels are analyzed on the test sample. Similarly, a total of five distinct sets of adjacent pairs of recessed regions of flexible binding channels are measured on the remaining four replicated test samples. Next, the arithmetic mean of all the flexible binding land region length values ​​recorded across all five test sample replicas is calculated and reported as the flexible binding land region length in units of 0.1 mm.

[0195] Five replication test samples are retained and used for subsequent measurements of flexible binding channel widths.

[0196] Flexible bonding channel width method: To measure the width "A" of the flexible bonded channel, a two-dimensional (2D) line profile (a subsample of the 3D surface image) is extracted from a position within one of the individual recessed regions within the flexible bonded channel region perpendicular to the long side of the recess (i.e., the line crosses the width of the recess). This line profile extends along its central transverse axis across the entire width of the individual channel recess and includes non-recessed regions directly adjacent to both sides of the channel. Those skilled in the art will know that if the resulting line profile does not generally represent the overall contour of the flexible bonded channel region due to measurement noise or the presence of localized wrinkles or malformed channels (i.e., channels with a depth of less than 1 mm as determined by the flexible bonded channel depth method described herein), then another test position in a separate recessed region of the flexible bonded channel should be measured so as not to be present for such artifacts. Here, a line height profile (height (mm) versus line length (mm)) is created. For example, as shown in Figure 15, it will be apparent to those skilled in the art that the flexible bonding channel region (minimum Z value) and the channel-free region (maximum Z value adjacent to the channel) are located on the height profile. This line profile shows an exemplary width of the recessed region within the flexible bonding channel. Determine the minimum height value (y-axis) on the line profile. Next, move along the left line of the profile in the z direction (y-axis) from the minimum height value to a position 200 microns away from the minimum height value and set a "left" marker on the line profile. Similarly, move along the right line of the profile in the z direction (y-axis) from the minimum height value to a position 200 microns away from the minimum height value and set a "right" marker on the line profile. Measure the horizontal x-distance between the left and right markers placed on the line profile and record it as the flexible bonding channel width in units of 0.1 mm. Now, repeat the entire procedure until a total of five distinct individual recessed regions of the flexible bonding channel have been analyzed on the test sample. Similarly, measure a total of five distinct individual recessed regions of the flexible bonding channel in the remaining four replicated test samples. Next, the arithmetic mean of all flexible bond channel width values ​​recorded across all five test sample replicas is calculated and reported as the flexible bond channel width "A" in units of 0.1 mm.

[0197] Hold five replicated test samples for subsequent measurement of the depth of the flexible coupling channel.

[0198] Flexible coupling channel depth method: Test samples from the flexible coupling channel width method are further prepared for channel depth measurement as follows. To indicate where the depth of the flexible coupling channel region is measured and subsequently where test specimens for the stiffness test are taken, draw a line approximately 35 mm long on the surface facing the body of the test sample within each of the flexible coupling channel regions (left and right). The left and right flexible coupling channel regions have a longitudinal direction generally parallel to the longitudinal axis of the absorbent article. Similarly, prepare the remaining four replicated test samples so that a total of ten flexible coupling channel regions (five on each side) can be analyzed. Numerically label each test sample (i.e., i - v) so that the test samples can be traced through each subsequent measurement.

[0199] The thickness of the first test sample is measured at a test location defined as the channel-free region of the test sample, located between the left and right flexible binding channel regions, excluding all portions of any existing flexible binding channel regions. Ideally, the test location is at the center of the absorbent article (the intersection of the transverse and longitudinal midpoints) and midway between the left and right flexible binding channel regions. The thickness of the test sample is measured mechanically with a manual micrometer equipped with a clamp capable of applying a constant pressure of 0.1 psi ± 0.01 psi (0.69 kPa ± 0.07 kPa). The manual micrometer is a self-weight instrument with accurate readings to 0.01 mm. A suitable instrument is the Mitutoyo Series 543 ID-C Digimatic, available from VWR International, or an equivalent. The clamp is a circular movable surface with a flat surface having a diameter of 25.4 mm. The test sample is supported by a horizontal, flat reference platform that is larger than the surface of the clamp and parallel to the surface of the clamp. Zero the micrometer relative to the horizontal, flat reference platform. Place the test sample on the platform with the test position centered under the clamp. Ensure that no part of the clamp is in contact with any part of any existing flexible bonding channel area, then lower the clamp by hand at a descent rate of 3 ± 1 mm / sec until the full pressure is applied to the sample. After 5 seconds, record the thickness as the thickness of the absorbent material Ti in 0.01 mm units. Repeat the thickness measurement for all five replicated test samples in the same manner, and record the pad thickness (i.e., Ti ~ Tv) for each in 0.01 mm units. Calculate the arithmetic mean for all five replicas and report it as the thickness of the absorbent material T in 0.01 mm units.

[0200] The 3D surface topography image of the first test sample i is obtained as follows. Move the test sample onto the MikroCAD (or equivalent) table under the camera. Orient the test sample such that the longitudinal axes of the left and right flexible coupling channel regions are orthogonal to the long axis (X-axis) of the instrument's field of view. Collect the 3D surface topography image of the test sample according to the measurement procedure recommended by the instrument manufacturer, which may include focusing the measurement system and performing brightness adjustment. No pre-filtering option is used. The collected height image file is saved to an evaluation computer running surface texture analysis software.

[0201] The 3D surface topography image is opened in surface texture analysis software. The following filtering procedures are then performed on the image: 1) removal of irregular points, 2) a 3x3 pixel median filter to remove noise, and 3) a 3x3 pixel average filter to smooth the surface. A two-dimensional (2D) line profile (subsampling of the 3D surface image) is extracted from a position perpendicular to the direction of the flexible bonded channel region. This line profile extends across the entire width of the test sample (from left to right) and intersects both the left and right flexible bonded channel regions on the test sample at 90 degrees. The line profile is drawn such that a 35 mm line intersects a portion of the channel previously drawn during sample preparation. Those skilled in the art will know that if the resulting line profile does not generally represent the overall contour of the flexible bonded channel region due to measurement noise or the presence of localized wrinkles or malformed channels, another test sample should be prepared and measured so that such artifacts are absent. Here, a line height profile (height (mm) versus line length (mm)) is created. For example, as shown in Figure 15, it will be apparent to those skilled in the art that the flexible-binding channel region (minimum Z value) and the channel-less region (maximum Z value between channels) are located on the height profile. This line profile shows the exemplary depth of the flexible-binding channel region relative to the channel-less region adjacent to and between the flexible-binding channel region present on the test sample. Export the raw data of the line height profile to .txt format.

[0202] The raw data of the line height profile is imported and processed in a spreadsheet program such as Excel or an equivalent. The Z minimum value of the flexible coupling channel region on the left side of test sample i is determined, and Zmin iL The measurement is recorded in units of 0.1 mm. Similarly, the minimum Z value of the flexible binding channel region on the right side of test sample i is determined, and Zmin iR The measurement is recorded in units of 0.1 mm. The height of the channelless region along the line between the left and right flexible coupling channel regions is Zmax iZmax i This is the calculated arithmetic mean of all height values ​​located along a 10 mm path length centered on the midpoint distance between the left and right flexible bonded channel regions along the line. However, if the channel-less region between the left and right flexible bonded channel regions is too narrow, and there is some compression due to the proximity of the channel regions, Zmax i The more appropriate channelless region is Zmax, so that it best represents the intended height of the channelless region of the article in the test sample. i Selected as Zmax. i From Zmin iL The depth of the left flexible coupling channel region of test sample i is calculated by subtracting the left channel depth D. iL It is recorded in units of 0.1 mm. Similarly, Zmax i From Zmin iR The depth of the right-side flexible coupling channel region of test sample i is calculated by subtracting the right-side channel depth D. iR The measurement is recorded in units of 0.1 mm. Next, the D measured for test sample i is recorded. iL and D iR The arithmetic mean of the values ​​is calculated and recorded as the channel depth Di in units of 0.1 mm. Similarly, channel depth measurements are repeated for all five replicated test samples i-v, so that a total of 10 flexible binding channel regions (5 on each side) are analyzed and the channel depth is recorded in units of 0.01 mm (i.e., Di-Dv) for each test sample. Next, the arithmetic mean of the five channel depths (Di-Dv) calculated for the five replicated test samples is calculated and reported as the dry channel depth D in units of 0.01 mm.

[0203] Each sample for repeated testing, labeled with a number, is retained for subsequent MD channel stiffness measurement.

[0204] Flexible coupled channel MD stiffness method: The MD stiffness of the prepared test specimens is measured on a general-purpose constant-velocity elongation (CRE) test frame or equivalent, such as that of the MTS Alliance, using TestSuite Software available from MTS Systems Corp. (Eden Prairie, MN). The CRE test frame comprises a three-point bending fixture and a load cell (preferably a 10N load cell) in which the force to be measured is within 1% to 99% of the cell's limit. A bottom stationary fixture consisting of two cylindrical bars made of polished stainless steel, with a diameter of 3.175 mm and a length of 110 mm, is mounted at each end using frictionless rolling bearings. These two bars are mounted horizontally, aligned front to back and parallel to each other, with their upper radii aligned vertically, and rotate freely around the diameter of the cylinder by frictionless bearings. Furthermore, the fixture allows the two bars to be moved horizontally away from each other on the track, so that a gap can be set between them while maintaining the orientation of the bars. The upper fixture consists of a third cylindrical bar, similarly 3.175 mm in diameter and 110 mm in length, made of polished stainless steel and fitted to each end with frictionless rolling bearings. When in position, the bars of the upper fixture are parallel to and aligned in the front-to-back direction with the bars of the lower fixture, and positioned centered between the bars of the lower fixture. Both fixtures include integrated adapters suitable for fitting and securing them in place at their respective positions on the universal test frame, so that the bars are perpendicular to the movement of the crossbeams of the test frame.

[0205] Specimens for measuring rigidity are prepared from test samples that have been previously prepared and number-labeled for measuring the depth of flexible bonded channels, as follows: Each individually prepared specimen is 5.3 mm wide and has a length of at least 35 mm. The width of the specimen is centered on the width of the flexible bonded channel region, and the length of the specimen is parallel to the longitudinal direction of the channel. The specimen contains a channel region in which a 35 mm line has been pre-drawn during specimen preparation. Two specimens are prepared from each number-labeled test sample, one from the bonded channel region on the left side of the test sample and one from the flexible bonded channel region on the right side of the test sample. Each specimen is obtained from the same region of the flexible bonded channel region previously analyzed for channel depth, indicated by the 35 mm line drawn during sample preparation. A total of 10 flexible bonded channel region specimens are prepared (5 on the left and 5 on the right) and number-labeled (i.e., i L ~v L and i R ~v R ).

[0206] The gap ("span") between each bar of the lower fixture is set to 20 mm ± 0.5 mm (from the center of one bar to the center of the other), and the center of the upper bar is aligned with the midpoint between each lower bar. First test specimen i L Apply a load to the upper bar, ensuring that its long side is perpendicular to the two lower bars of the fixture and rests on them, and that the body-facing surface of the specimen is facing the upper bar and is centered below the upper bar. Move the vertical position of the upper bar until its bottom edge is 1 mm above the surface of the specimen, then set the crosshead position to 0.

[0207] A universal test frame for the bending test is programmed so that the crosshead moves downward at a speed of 1.0 mm / second relative to the lower fixture over a total distance of 12 mm from the 0 position. The crosshead is then immediately returned to its original gauge at a speed of 1.0 mm / second. Force (N) and displacement (mm) data are collected continuously at 50 Hz throughout the test. The width of the test specimen is recorded as 5.3 mm. The test is started, and time, force, and displacement data are collected continuously.

[0208] The graph of force (N) versus displacement (mm) is shown for test specimen i. L To create this, determine the maximum peak force from the graph, and determine the flexible coupling channel MD peak load and MD peak. iL It is recorded in units of 0.01N. The slope of the initial straight portion of the curve before the peak is calculated, and the rigidity of the flexible bond channel MD is determined. iL The energy is recorded in units of 0.005 N / mm. The energy to the peak is calculated as the area below the force-displacement curve from the initial point to the peak force, and the flexible coupling channel MD energy to the peak is calculated as MDPE. iL For example, 0.01N * Record in millimeters. Similarly, test specimen i taken from the right channel of test specimen i R Repeat the entire procedure for the left test specimen i. L and right test piece i R For each parameter, calculate the arithmetic mean over the values ​​obtained for the dry MD peak. i The dry MD stiffness was recorded in units of 0.01 N. i The values ​​were recorded in units of 0.005 N / mm for dried MDPE. i For example, 0.01N * Record in millimeters. Similarly, all 10 flexible binding channel region test specimens (i) taken from test samples i-v. L ~v L and i R ~v RRepeat the procedure for ). Calculate the arithmetic mean of each parameter over the values ​​obtained for test samples i to v and report it as the dry MD peak in units of 0.01 N. Report the dry MD stiffness in units of 0.005 N / mm and the dry MD energy PE to the peak in units of 0.01 N. * Report in millimeters.

[0209] Flexible coupled channel CD rigidity-flexibility method: The CD stiffness of a new set of prepared test specimens is measured on the same general-purpose constant-rate elongation (CRE) test frame, using the same three-point bending fixture and load cell as previously described for MD stiffness measurement.

[0210] A new set of test specimens is prepared as follows: The absorbent article is unfolded as necessary, and then the protective cover (i.e., wrapping paper or release paper) on the panty-fixing adhesive is removed. Talc powder is lightly sprinkled on the adhesive to reduce its stickiness. The test specimens have a width of 25.4 mm (parallel to the longitudinal axis of the article) and a length equal to the distance from the left edge to the right edge of the article (approximately 70 mm). The test specimens are taken from an area of ​​the article where the flexible bonding channel area is oriented parallel to the longitudinal axis of the article, and the selected area is free of crease or wrinkle residue. Ideally, the test specimens are obtained from the center of the article (the intersection of the longitudinal and transverse centerlines). A total of 10 duplicate test specimens are prepared. The specimen is mounted on a three-point bending fixture such that five "channeled" replicas bend along the binding channel (i.e., the upper central blade is parallel to the channel and its center is above the channel), and the other five "non-channeled" replicas bend along the non-channeled region of the specimen.

[0211] Set the gap ("span") between each bar of the lower fixture to 25 mm ± 0.5 mm (from the center of one bar to the center of the other), and align the center of the upper bar with the midpoint between each lower bar. Mount the first "channeled" specimen so that it rests on the two lower bars of the fixture with the lateral outer edge of the specimen oriented parallel to the bars. Adjust the position of the specimen so that the body-facing surface of the specimen faces the upper bar, the bonding channel is parallel to the upper bar, and its center is below the upper bar. At this position, the specimen is bent along the flexible bonding channel region. Move the vertical position of the upper bar until its bottom edge is 1 mm above the surface of the specimen, and then set the crosshead position to 0. Program the universal test frame for the bending test so that the crosshead moves so that the upper fixture moves downward relative to the lower fixture at a speed of 1.0 mm / second over a total distance of 12 mm from the 0 position. Next, immediately return the crosshead to its original gauge at a speed of 1.0 mm / second. Force (N) and displacement (mm) data are collected continuously at 50 Hz throughout the test. The width of the test specimen is recorded as 25.4 mm. Start the test and continuously collect time, force, and displacement data.

[0212] A graph of force (N) versus displacement (mm) is created for the channeled specimen. The slope of the first straight portion of the curve is calculated and recorded in units of 0.005 N / mm as the dry flexible bonded channel CD stiffness. The entire procedure is repeated similarly for a total of five "channeled" specimens. Next, the arithmetic mean of the slope values ​​across the five "channeled" specimens is calculated and reported in units of 0.005 N / mm as the dry flexible bonded channel CD stiffness.

[0213] The "no channel" specimen is tested similarly, except for the positioning of the specimen. The "no channel" specimen is mounted on a three-point bending fixture so that its lateral outer edge is oriented parallel to the bars and rests on the two lower bars of the fixture. The specimen is positioned so that the no-channel area of ​​the specimen is centered below the upper bar and the body-facing surface of the specimen faces the upper bar. At this position, the specimen is bent along a region that does not contain any part of the flexible bond channel area. The vertical position of the upper bar is moved until the bottom edge of the upper bar is 1 mm above the surface of the specimen, and then the crosshead position is set to 0. The test is then performed as described above, and time, force, and displacement data are collected continuously.

[0214] A graph of force (N) versus displacement (mm) is created for the "no channel" specimen. The slope of the first straight section of the curve is calculated and recorded as the dry no-channel CD stiffness in units of 0.005 N / mm. The entire procedure is repeated similarly for a total of five "no channel" specimens. Next, the arithmetic mean of the slope values ​​across the five "no channel" specimens is calculated and reported as the dry no-channel CD stiffness in units of 0.005 N / mm.

[0215] Examples / Data The following data and examples, including comparative examples, are provided to aid in illustrating the upper and lower nonwoven layers, absorbent core structures, and / or absorbent articles described herein. The illustrated structures are provided for illustrative purposes only and many modifications thereto are possible without departing from the spirit and scope of this disclosure, and should not be construed as limiting the invention.

[0216] Nonwoven fabric material testing The nonwoven fabric layer material was tested to evaluate its ability to generate strain (stretch) under balanced elongation and its ability to recover to its original state (simulating physical deformation during use). Samples F to H are comparative examples. The tests were carried out according to the CD periodic stretch method up to 3% strain and the fracture strain method described herein. The results are shown in Table 1.

[0217]

Table 1

[0218] Suitable nonwoven layer materials have been found to strain (stretch) with a balanced stretch-to-recovery behavior. If the nonwoven layer material plastically stretches (i.e., is stretched but does not recover) as the fluff / AGM matrix in the inner core layer stretches, the recovery energy to return to the initial pre-stretch state becomes insufficient, and the nonwoven layer material becomes permanently strained (stretched). The upper nonwoven layer of this disclosure may have a permanent strain value of less than about 0.013. At the same time, if the nonwoven layer material is actively strained, for example, more than 5%, the nonwoven layer material must maintain its integrity and not rupture or break (see, for example, sample H, which ruptures and has a fracture strain of less than 5%). The nonwoven layer of this disclosure may have a fracture strain of more than about 10%.

[0219] The nonwoven fabric layer materials described above are also evaluated for their ability to bend, deform, and return to their original state. This test is performed according to the wet and dry CD ultra-high sensitivity three-point bending method described herein. The results are shown in Table 2.

[0220] [Table 2]

[0221] During walking, the absorbent material is compressed and bent from side to side in a periodic pattern as the gap between the wearer's legs narrows and then widens with the wearer's leg movement. While not limited by theory, approximately 2N * Nonwoven fabric layer materials with a dry bending energy of less than mm readily induce this bending compression, but are not considered to have enough stiffness to prevent it. At the same time, following the bending compression, the nonwoven fabric layer must be able to maintain sufficient dry recovery energy to return the fluff / AGM matrix in the nonwoven fabric layer and the inner core layer to its initial pre-bending state. The upper nonwoven fabric layer of this disclosure has a dry bending energy of approximately 0.03 N * It may have a drying recovery energy value exceeding mm.

[0222] Samples A-E have dry peak loads of 0.03N-0.38N and 0.032N-0.092N.* The dry recovery energy is shown to be 0.01N and 0.03N, respectively, demonstrating that these materials bend easily and have sufficient dry recovery energy to return to their initial pre-bending state. Comparative examples Samples F and G were subjected to dry peak loads of 0.01N and 0.03N, respectively, and 0.005N, respectively. * mm and 0.019N * The dry recovery energy is shown to be 0.04N, demonstrating that these materials bend easily but do not have enough recovery energy to return to their initial pre-bending state after compression. Sample H (comparative example) under a dry peak load of 0.04N and 0.031N * It exhibits a dry recovery energy of mm. However, sample H is found to tear when wet and is insufficient to function as the upper and / or lower nonwoven layers of the present disclosure.

[0223] While not limited by theory, nonwoven fabric layer materials containing thick fibers (approximately 2.0 DTex to 10 DTex) arranged within a reticular structure are thought to be able to bear mechanical loads within the fibrous reticular structure and return the absorbent core structure and / or absorbent article to its initial shape after bending and compression. Samples F and G contain relatively thin fibers (less than approximately 2.0 DTex), while samples A to E contain fiber blends with fiber thicknesses of approximately 2.2 DTex to 10 DTex.

[0224] Absorbable core structure testing The absorbent core structure is tested to evaluate its ability to compress (simulating the compression experienced between the wearer's legs) and recover to its original state. Examples 1-3 in Table 3 show the absorbent core structures described herein. Comparative Examples A-C are comparative examples. Table 3 provides a description of Examples 1-3 and Comparative Examples A-C. The absorbent core structure is prepared as described below. The absorbent core structure is evaluated according to the wet and dry cluster compression methods described herein. The results are shown in Table 4.

[0225] [Table 3] 1 Available from Xiamen Yanjan New Material Co. (China) as ATB Z87G-40. 3 Available from Sandler GmbH (Germany) as Sawasoft® 553FC041005 (Option 82). 4 Available as Aura 20 from Xiamen Yanjan New Material Co. (China). 5 Available from Jacob Holms Industries (Germany) as S25000541R01. 6 Available from dPFNonwovens Czech SRO (Czech Republic) as PFNZN 18G BICO8020 PHI 6. 8 Available from DunnPaper (USA) as product number 3028. 9 Available from Evonik (Germany) as Favor SXM9745. 10 Available from Resolute Alabama (USA) as item 9E3-COOSABSORB S. 11 Available from Fitesa (Germany) as item 4004416 (MR3585374).

[0226] The absorbent core structures listed in Table 3 are produced as detailed herein. Specifically, the upper nonwoven layer is first introduced onto a molding drum in a laydown section and stretched into a three-dimensional pocket shape under vacuum. A homogeneous flow of fluff (cellulose) and AGM material is deposited directly onto the upper nonwoven layer in the molding station. Before entering the molding station, the upper nonwoven is coated with a spray adhesive (Technomelt DM 9036U, 6gsm continuous meltblown spiral, 50mm wide, available from Henkel (Germany)) to provide a stronger bond to the upper nonwoven layer of fluff (cellulose) and AGM without hindering the flow of liquid into the fluff / AGM matrix. As it exits the laydown section, the lower nonwoven web is combined with the nonwoven carrying the homogeneous blend of fluff / AGM. This lower nonwoven fabric is pre-coated with adhesive (Technomelt DM 9036U, available from Henkel (Germany)) to allow for a perimeter seal (10gsm meltblown spiral, 20mm wide on the sides), and in the center, a 6gsm, 50mm wide continuous meltblown spiral adhesive (Technomelt DM 9036U, available from Henkel (Germany)) is applied to better integrate the fluff / AGM matrix.

[0227] Examples 1-3 and Comparative Examples A and B also have the structural bonding shown in Figure 4, which has the profile shown in Figure 5. Examples 1-3 and Comparative Examples A and B have a structural bonding spacing of 32 mm × 16 mm, thereby occupying 1.38% of the total structural bonding area of ​​the total area of ​​the absorbent core structure. Comparative Example C is identical to Comparative Example B except that the structural bonding spacing is 10 mm × 10 mm, thereby occupying 6.28% of the total structural bonding area of ​​the total area of ​​the absorbent core structure. The structural bonding is applied using a heated aluminum die to form an embossed pattern in a heated hydraulic press. The structural bonding embossed plate is 3.55 mm, as shown in Figure 4. 2It has a surface area and protrusions with a height of approximately 1 mm, and has the profile shown in Figure 5. The structural bonds are spaced apart according to the dimensions of the separation described above. The structural bond embossing plate is heated to 120°C and set to a compression pressure of 170 kPa. The absorbent material is placed and oriented under the heated embossing plate on the hydraulic press bottom plate, and a thin sheet of Teflon® film is placed on top of the sample before embossing to avoid melting of the top sheet fibers. The hydraulic press is activated and the sample is compressed for a residence time of 1.7 seconds to create the structural bond pattern.

[0228] Examples 1-3 and Comparative Examples A-C also have flexible bonded channel regions to which the patterns shown in Figure 7A are applied. The flexible bonded channel regions are applied using a heated aluminum die and the embossed pattern is generated in a heated hydraulic press. The flexible bonded channel embossing plate has projections spaced about 1.5 mm apart, with a length of about 3 mm and a width of about 1.5 mm. The bonded channel embossing plate is heated to 120°C and set to a compression pressure of 200 kPa. The absorbent material is placed and oriented under the heated embossing plate on the hydraulic press bottom plate, and a thin sheet of Teflon® film is placed on top of the sample before embossing to avoid melting of the top sheet fibers. The hydraulic press is activated and the sample is compressed for a residence time of 1.7 seconds to create the embossed pattern.

[0229] [Table 4]

[0230] It has been found that an absorbent core structure containing a nonwoven fabric layer material with sufficient elasticity and recovery energy can be restored to its original shape before compression. Examples 1-3 use 1.0N. *These structures exhibit a fifth-cycle wet recovery energy exceeding mm and a fifth-cycle wet maximum compressive force of 207 gf to 213 gf. While these structures exhibit lower compressive forces (and therefore feel softer and more flexible due to their lower resistance), they can still recover their shape as the structures are periodically compressed and released. However, comparative examples A to C exhibit 0.26 to 0.59 N. * This shows the wet recovery energy for the fifth cycle in mm. If there is insufficient recovery energy after five cycles of compression, comparative examples A to C remain in a clustered state compressed with insufficient force (storage energy) to recover their original pre-compression shape.

[0231] The absorbent core structure and / or absorbent article of this disclosure has a density of approximately 1.0 N * Over 1 mm, or approximately 1.0 to 3.5 N * The fifth-cycle wet recovery energy may be mm. The absorbent core structure and / or absorbent article of this disclosure may have a fifth-cycle wet maximum compressive force greater than about 150 gf, preferably greater than about 200 gf, or about 150 gf to about 225 gf.

[0232] While individual nonwoven materials may possess sufficient fracture strain percentage in the fracture strain method, it has been found that when incorporated into an absorbent core structure, the nonwoven material may not provide enough recovery energy for the entire absorbent core structure to return to its original pre-compression shape (for example, in Comparative Example A). For example, in Comparative Example A, the basis weight and thickness of the fibers of the upper nonwoven material when combined with a thin lower nonwoven material are 1.0 N. * It provides fifth-cycle wet recovery energy of less than mm.

[0233] Final product testing The absorbent articles are tested to evaluate the ability of the wrapped absorbent core structure to compress (simulating the compression received between the wearer's legs) and recover to its original state. Examples 4-7 show the absorbent articles described herein. Comparative Examples D and E are comparative examples. Comparative Examples F-L are commercially available final products. Descriptions of Examples 4-7 and Comparative Examples D-E are listed in Table 5a. Descriptions of Comparative Examples F-L are listed in Tables 5b and 5c. Examples 4-7 and Comparative Examples D and E are prepared as described below. The absorbent articles in Tables 5a and 5b are evaluated according to the wet and dry CD and MD three-point bending method, the wet and dry cluster compression method, and the light touch re-wetting method as described herein. The results are shown in Table 6.

[0234] [Table 5] 1 Available from Xiamen Yanjan New Material Co. (China) as ATB Z87G-40. 2 Available from Sandler GmbH (Germany) as Sawasoft (registered trademark) 53FC041001. 3 Available from Sandler GmbH (Germany) as Sawasoft® 553FC041005 (Option 82). 4 Available as Aura 20 from Xiamen Yanjan New Material Co. (China). 5 Available from Jacob Holms Industries (Germany) as S25000541R01. 6 Available from dPFNonwovens Czech SRO (Czech Republic) as PFNZN 18G BICO8020 PHI 6. 8 Available from DunnPaper (USA) as product number 3028. 9Available from Evonik (Germany) as Favor SXM9745. 10 Available from Resolute Alabama (USA) as item 9E3-COOSABSORBS. 12 The nonwoven top sheet "Nonwoven SG" is a nonwoven web as described in U.S. Patent Application Publication No. 2019 / 0380887.

[0235] [Table 6]

[0236] [Table 7]

[0237] Examples 4-7 and Comparative Examples D and E include structures detailed in Examples 1-3 of Table 3, having the same adhesive design and the same 32 mm × 16 mm structural bonding pattern in the absorbent core structure (total structural bonding area of ​​1.38% of the total area of ​​the absorbent core structure). In addition, the absorbent article includes a nonwoven top sheet web, as detailed in U.S. Patent Application Publication No. 2019 / 0380887, bonded to the absorbent core structure by spray adhesive (Technomelt DM 9036U, 3 gsm continuous meltblown spiral, 50 mm wide, 150 mm long, available from Henkel (Germany)). In addition, a 12gsm polypropylene backsheet is bonded to the outer surface of the lower nonwoven fabric by applying a spray adhesive (Technomelt DM 9036U, 3gsm continuous meltblown spiral, 50mm wide, 150mm long, available from Henkel (Germany)).

[0238] Examples 4-7 and Comparative Examples D and E also have the structural bond shown in Figure 4, which has the profile shown in Figure 5. The structural bond is applied using a heated aluminum die to form an embossed pattern in a heated hydraulic press. The structural bond embossed plate is 3.55 mm, as shown in Figure 4. 2 It has a surface area and protrusions approximately 1 mm high, and has the profile shown in Figure 5. The structural bonds are spaced according to the dimensions of the separations described above. The structural bond embossing plate is heated to 120°C and set to a compression pressure of 170 kPa. The absorbent material is placed and oriented under the heated embossing plate on the hydraulic press bottom plate, and a thin sheet of Teflon® film is placed on top of the sample before embossing to avoid melting of the top sheet fibers. The hydraulic press is activated and the sample is compressed for a residence time of 1.7 seconds to create the structural bond pattern.

[0239] Before bonding the backsheet, the flexible bonding channel region is applied to Examples 4-7 and Comparative Examples D and E with the pattern shown in Figure 7A. The flexible bonding channel region is applied using a heated aluminum die to create the embossed pattern within a heated hydraulic press. The flexible bonding channel embossing plate has projections spaced approximately 1.5 mm apart, with a length of approximately 3 mm and a width of approximately 1.5 mm. The bonding channel embossing plate is heated to 120°C and set to a compression pressure of 200 kPa. The absorbent material is placed and oriented under the heated embossing plate on the hydraulic press bottom plate, and a thin sheet of Teflon® film is placed on top of the sample before embossing to avoid melting of the topsheet fibers. The hydraulic press is activated and the sample is compressed for a residence time of 1.7 seconds to create the embossed pattern.

[0240] [Table 8]

[0241] To provide high biocompatibility, the absorbent articles of this disclosure have a density of approximately 10 to 30 N.* mm 2 , or approximately 10 to approximately 25N * mm 2 It is thought that it can exhibit low CD dry bending stiffness (i.e., high flexibility). Furthermore, in order to provide an absorbent article that can be compressed in accordance with body movement and return to its original pre-compression state relative to the user's body, the absorbent article of this disclosure has a stiffness of approximately 1.0 to approximately 3.5 N. * It is believed that the fifth-cycle wetting recovery energy may be mm and / or a fifth-cycle wetting recovery percentage of about 29% to about 40%. The absorbent articles of this disclosure can also maintain good fluid handling, resulting in low light-touch rewetting of about 0 to about 0.15 g.

[0242] Examples 4-7 are 13.0-18.7N * mm 2 The CD dry bending stiffness and the 5th cycle wet recovery percentage in wet and dry cluster compression methods of 29-36% demonstrate that these structures can maintain their shape during use. Comparative Examples D and E are 9.1 and 13.0 N, respectively. * mm 2 The CD dry bending stiffness is shown. However, comparative examples D and E show a wet recovery % of less than 29% in the 5th cycle of the wet and dry cluster compression method, demonstrating that these structures cannot maintain their shape during use and remain clustered. Comparative examples F to L are commercially available finished products and have a stiffness of 29 to 47.5 N. * mm 2 The CD dry bending stiffness is shown, demonstrating that the structure has low flexibility and poor conformability.

[0243] While not limited by theory, it is believed that sufficient recovery energy is required to push the absorbent material on the panties back to its pre-compression shape in order to maintain comfortable shape recovery after compression. Simultaneously, the absorbent material (through the absorbent core structure) needs to recover along the same path as it was compressed to return to its pre-compression position. The wet recovery energy for the fifth cycle is approximately 1.0 N. *If the value is less than mm, the absorbent material may not have the recovery energy necessary to restore its shape. If the fifth-cycle wet recovery energy value is too high, the recovery may be too strong, causing the wearer to feel that the absorbent material does not stay in place. If the fifth-cycle wet recovery % value is low (less than approximately 29%), the absorbent material may not return to its pre-compression shape and may remain deformed and clumped together. If the fifth-cycle wet recovery % value is excessively high (greater than approximately 40%), it is suggested that the absorbent material may recover too strongly to a flat shape when first applied to the wearer's panties, in contrast to its shape on the wearer's body.

[0244] Structural bonding test The absorbent core structure is tested to evaluate the influence of structural bonding regions on flexibility and bending stiffness. Example 8 does not feature any structural bonding within the absorbent core structure. Examples 9 and 10 have structural bonding shown in Figure 4 with the profile shown in Figure 5. Examples 8 to 10 are prepared as described below. The results of the wet and dry MD three-point bending method are shown in Table 7.

[0245] [Table 9] 3 Available from Sandler GmbH (Germany) as Sawasoft® 553FC041005 (Option 82). 9 Available from Evonik (Germany) as Favor SXM9745. 10 Available from Resolute Alabama (USA) as item 9E3-COOSABSORBS. 13 Available as 10 SMS PHILIC from Union Industries SpA. (Italy).

[0246] Table 7 shows the effect of the total structural connection area and spacing. The asymmetric structural connection shape shown in Figure 4 and the profile shown in Figure 5 are 3.55 mm.2 It has the maximum area. The MD dry bending stiffness is found to increase with the structural bond area. Example 8 has a non-structural bond and is 9.8N * mm 2 This shows the MD dry bending stiffness. Example 9 has a structural bond spacing of 32 mm × 16 mm (total structural bond area of ​​1.38% of the total area of ​​the absorbent core structure) and has a stiffness of 19.2 N. * mm 2 This shows the MD dry bending stiffness. Example 10 has a structural bond spacing of 16 mm × 16 mm (total structural bond area of ​​3.96% of the total area of ​​the absorbent core structure) and has a stiffness of 29.6 N * mm 2 This indicates the MD dry bending stiffness. To maintain a flexible and conformable absorbent core structure and / or absorbent article in the wear-to-wear (MD) direction, the absorbent core structure and / or absorbent article should have a dry bending stiffness of approximately 10 to approximately 30 N. * mm 2 It is considered that it can have MD dry bending rigidity.

[0247] The absorbent core structures listed in Table 7 are produced as detailed herein. Specifically, a 50gsm elastic spunlace 6 upper nonwoven is first introduced onto a forming drum in a laydown section and stretched into a three-dimensional pocket shape under vacuum. A homogeneous flow of fluff (cellulose) and AGM material is deposited directly onto the upper nonwoven material in the forming station. Before entering the forming station, the upper nonwoven is coated with a spray adhesive (Technomelt DM 9036U, 6gsm continuous meltblown spiral, 50mm wide, available from Henkel (Germany)) to provide a stronger bond to the fluff (cellulose) and AGM upper nonwoven layer without obstructing the flow of liquid to the fluff / AGM mass. As it exits the laydown section, a 10gsm SMS lower nonwoven web is combined with the nonwoven carrying the homogeneous blend of fluff (cellulose) and AGM layer. The lower nonwoven fabric is pre-coated with an adhesive (Technomelt DM 9036U, available from Henkel (Germany)) to enable a periphery seal (10 gsm meltblown spiral, 20 mm wide on the sides), and in the center, a 6 gsm, 50 mm wide continuous meltblown spiral adhesive (Technomelt DM 9036U, available from Henkel (Germany)) is applied to better integrate the fluff / AGM mass. Structural bonding as shown in Figure 4, with the profile shown in Figure 5, is applied to Examples 9 and 10. The structural bonding in Example 9 has a spacing of 32 mm × 16 mm, thereby occupying 1.38% of the total structural bonding area of ​​the absorbent core structure. The structural bonding in Example 10 has a spacing of 16 mm × 16 mm, thereby occupying 3.96% of the total structural bonding area of ​​the absorbent core structure with this structural bonding profile. The total area of ​​the absorbent core structure is measured according to the structural bonding site pattern spacing and area measurement method. Structural bonding is applied in the same manner as described above for Examples 1-3 and Comparative Examples A and B.

[0248] Flexible binding channel region testing Absorbent articles are tested to evaluate the effect of the flexible bond channel region on the MD and CD dry stiffness. In particular, absorbent articles are tested to evaluate the ability of the flexible bond channel region to bend in the MD, i.e., longitudinal (or front-to-back) direction (see Table 9), and in the CD (left-to-right direction) direction (see Table 10). Example 11 shows an absorbent article described herein. Comparative Examples M to Q are commercially available finished products having embossed channels. A description of Example 11 is listed in Table 8a. A description of Comparative Examples M to Q is listed in Tables 8b and 8c. Example 11 is prepared as described for Example 4 in Table 5a above. Example 11 and Comparative Examples M to Q are evaluated according to the flexible bond channel depth method and the flexible bond channel MD stiffness method, and the results are shown in Table 9. Example 11 is evaluated according to the flexible bond channel CD stiffness method, and the results are shown in Table 10.

[0249] [Table 10] 1 Available from Xiamen Yanjan New Material Co. (China) as ATB Z87G-40. 6 Available from dPFNonwovens Czech SRO (Czech Republic) as PFNZN 18G BICO8020 PHI 6. 9 Available from Evonik (Germany) as Favor SXM9745. 10 Available from Resolute Alabama (USA) as item 9E3-COOSABSORBS. 12 The nonwoven top sheet "Nonwoven SG" is a nonwoven web as described in U.S. Patent Application Publication No. 2019 / 0380887.

[0250] [Table 11]

[0251] [Table 12]

[0252] [Table 13]

[0253] Example 11 exhibits a depth-to-thickness ratio of 69%, but is found to have a clearly defined flexible bond channel region that requires only a smaller force of 0.0969 N to bend and only a dry MD stiffness of 0.0244 N / mm. In contrast, Comparative Examples M-Q have depth-to-thickness ratios of 33%-66% and require a force of 0.2074 N-0.518 N to bend. Comparative Examples M-Q also exhibit dry MD stiffness of 0.0459-0.1305, demonstrating that the channel-like structures in these products have higher resistance to bending (i.e., lower flexibility). While not limited by theory, consumers wearing the absorbent articles shown in Example 11 are likely to experience products that conform to their bodies with less resistance and pressure, resulting in absorbent articles that conform more closely and comfortably.

[0254] [Table 14]

[0255] It can be seen that the dry flexible bond CD stiffness in the flexible bond channel region is lower than in the channel-less region adjacent to the flexible bond channel region. Example 11 exhibits a CD stiffness index of 1.7 (ratio of dry channel-less CD stiffness to dry flexible bond CD stiffness). This supports the idea that the flexible bond channel region can be easily bent in channels with lower CD stiffness. Looking at Tables 9 and 10 together, it can be seen that the dry CD stiffness and dry MD stiffness values ​​of Example 11 are comparable to those of Comparative Examples M-Q and are considerably lower than those of Comparative Examples M-Q. Example 11 demonstrates low resistance to bending in both the MD and CD directions, and therefore, it is considered that Example 11 can closely and comfortably conform to a wide range of anatomical body shapes.

[0256] Combinations / Examples Paragraph A. A disposable absorbent article comprising a front end region, a rear end region, an intermediate region disposed between the front end region and the rear end region, a top sheet, a back sheet, and an absorbent core structure disposed between the top sheet and the back sheet, the absorbent core structure comprising (a) an upper nonwoven fabric layer containing polymer fibers, (b) a lower nonwoven fabric layer containing polymer fibers, and (c) an inner core layer disposed between the upper nonwoven fabric layer and the lower nonwoven fabric layer, the inner core layer containing cellulose fibers and superabsorbent particles; and a disposable absorbent article comprising a flexible bonded channel region formed in at least the intermediate region, having a dry channel depth of at least 1.0 mm and a channel width of about 1.0 mm to about 3.0 mm, a CD stiffness index of about 1.1 to about 3.0 and a dry MD stiffness of less than about 0.04 N / mm, preferably about 0.005 to about 0.035 N / mm, when measured according to the flexible bonded channel MD stiffness method.

[0257] Paragraph B. The disposable absorbent article according to Paragraph A, wherein the flexible binding channel region has a minimum channel length of at least about 50 mm.

[0258] Paragraph C. The disposable absorbent article according to paragraph A or B, wherein the flexible bond channel region includes one or more flexible bond embossments and one or more flexible bond land regions disposed between each of the flexible bond embossments.

[0259] Paragraph D. The disposable absorbent article described in Paragraph C, wherein the thickness "T2" of each flexible bond land region may be approximately 50% to approximately 70% of the thickness "T" of the absorbent article.

[0260] Paragraph E. The disposable absorbent article according to Paragraph C or D, wherein the flexible bond emboss has an embossed area, the flexible bond channel region has a channel area, and the embossed area is 22% to 65% of the channel area.

[0261] Paragraph F. Flexible bonded embossing is a disposable absorbent article described in any one of paragraphs C to E, having an embossing length of approximately 1.0 mm to approximately 4.0 mm.

[0262] Paragraph G. A disposable absorbent article as described in any one of Paragraphs C to F, wherein each flexible binding land region has a length of approximately 0.5 mm to approximately 4 mm.

[0263] Paragraph H. An absorbent article is a disposable absorbent article as described in any one of paragraphs A to G, comprising an inner flexible binding channel region and an outer flexible binding channel region.

[0264] Paragraph I. Absorbent materials have a concentration of approximately 0.045 g / cm³. 3 ~Approx. 0.15g / cm 3 A disposable absorbent article having the average density of one of the paragraphs A to H.

[0265] J. The upper nonwoven fabric is a disposable absorbent article as described in any one of paragraphs A to I, having a basis weight of approximately 35 gsm to approximately 85 gsm.

[0266] K. The lower nonwoven fabric is a disposable absorbent article described in any one of paragraphs A to J, having a basis weight of approximately 10 gsm to approximately 40 gsm.

[0267] Paragraph L. The inner core layer of the disposable absorbent article, as described in any one of Paragraphs A to K, contains cellulose fibers of approximately 125 to 400 gsm.

[0268] Paragraph M. A disposable absorbent article according to any one of Paragraphs A to L, wherein the inner core layer comprises approximately 50% to approximately 85% by weight of cellulose fibers and approximately 15% to approximately 50% by weight of superabsorbent particles in the inner core layer.

[0269] Paragraph N. Absorbent articles measured according to the wet and dry CD and MD three-point bending method were approximately 10 N. * mm 2 ~About 30N * mm 2 A disposable absorbent article according to any one of paragraphs A to M, having a CD dry bending stiffness and a fifth-cycle wet recovery rate of approximately 29% to approximately 40% when measured according to the wet and dry cluster compression method.

[0270] Paragraph O. The flexible binding channel region is 0.05 g / cm³. 3 ~0.3g / cm 3 A disposable absorbent article having the channel density described in any one of paragraphs A to N.

[0271] Paragraph P. Absorbent articles further include structural binding sites, and in some configurations, the structural binding sites are approximately 2 mm 2 ~about 5mm 2 A disposable absorbent article having the binding area of ​​any one of paragraphs A to O.

[0272] Paragraph Q. A disposable absorbent article comprising a top sheet, a back sheet, and an absorbent core disposed between the top sheet and the back sheet, wherein the top sheet forms the surface facing the wearer of the absorbent article, and the back sheet forms the surface facing the outside of the absorbent article, the absorbent core structure comprising (a) an upper nonwoven fabric layer containing polymer fibers, (b) a lower nonwoven fabric layer containing polymer fibers, and (c) an inner core layer disposed between the upper nonwoven fabric layer and the lower nonwoven fabric layer, wherein the inner core layer contains cellulose fibers and superabsorbent particles, the inner core layer contains cellulose fibers of about 125 gsm to about 400 gsm, and the surface facing the wearer of the absorbent article has a dry MD stiffness of less than about 0.04 N / mm and about 0.05 g / cm² when measured according to the flexible bond channel MD stiffness method. 3 ~about 0.3g / cm 3 A disposable absorbent article comprising a flexible bonded channel region having a channel density of [value].

[0273] Paragraph R. The flexible binding channel region has a channel depth of at least 1 mm, as described in Paragraph Q of the disposable absorbent article.

[0274] Paragraph S. The flexible binding channel region has a channel width of approximately 1.0 mm to approximately 3.0 mm, as described in Paragraph Q or R of the disposable absorbent article.

[0275] Paragraph T. The flexible binding channel region has a minimum channel length of approximately 50 mm, as described in any one of paragraphs Q to S.

[0276] Paragraph U. A disposable absorbent article as described in any one of paragraphs Q to T, wherein the absorbent article has thickness, and the flexible binding channel region has an average channel depth of about 20% to about 80% of the thickness of the absorbent article.

[0277] Paragraph V. A disposable absorbent article according to any one of paragraphs Q to U, wherein the outward-facing surface includes one or more flexible bonding depressions.

[0278] Paragraph W. A disposable absorbent article comprising: a top sheet, a back sheet, an absorbent core structure disposed between the top sheet and the back sheet, comprising: an upper nonwoven fabric layer containing polymer fibers, and an inner core layer containing cellulose fibers of about 125 gsm to about 400 gsm, wherein the inner core layer has a surface facing the wearer and a surface facing the outside, and the upper nonwoven fabric layer is in direct contact with the surface of the inner core layer facing the wearer; and a flexible bonded channel region comprising one or more flexible bonded embossments having an embossment length of about 1.0 mm to about 4.0 mm, having a channel depth of at least 1.0 mm and a channel width of about 1.0 mm to about 3.0 mm, and having a dry MD stiffness of less than about 0.04 N / mm when measured according to the flexible bonded channel MD stiffness method.

[0279] Paragraph Y. The disposable absorbent article according to Paragraph W, wherein the absorbent core structure further comprises a lower nonwoven fabric layer containing polymer fibers, which is in direct contact with the outward-facing surface of the inner core layer.

[0280] Paragraph X. The area of ​​one or more flexible bond embossments may be approximately 22% to approximately 65% ​​of the area of ​​the flexible bond channel region, as described in paragraphs W to Y.

[0281] Paragraph Z. One or more flexible binding channel regions contain approximately 0.05 g / cm³ of binding channel. 3 ~about 0.3g / cm 3 A disposable absorbent article having the channel density described in paragraphs W to X.

[0282] Paragraph A1. The disposable absorbent article described in paragraphs A to Z, wherein the inner core layer is contained within the nonwoven fabric layer by substantially sealing at least the left and right regions of the upper nonwoven fabric layer and the lower nonwoven fabric layer.

[0283] The dimensions and values ​​disclosed herein should not be understood as being strictly limited to the exact numerical values ​​listed. Instead, unless otherwise specified, each such dimension is intended to mean both the listed value and the functionally equivalent range encompassing that value. For example, a dimension disclosed as "40 mm" is intended to mean "approximately 40 mm."

[0284] All documents cited herein, including cross-referenced documents or related patents or applications, are incorporated herein in their entirety by reference unless expressly excluded or otherwise limited. No citation of any document shall be deemed prior art to any invention disclosed or claimed herein, nor shall it be deemed to teach, suggest or disclose any such invention, either alone or in combination with any one or more other references. Furthermore, in the event of any conflict between the meaning or definition of any term in this document and the meaning or definition of the same term in any document incorporated by reference, the meaning or definition given to the term in this document shall prevail.

[0285] While specific embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, it is intended that all such changes and modifications within the scope of the invention be covered in the appended claims.

Claims

1. Disposable absorbent articles, Front end region, rear end region, and intermediate region disposed between the front end region and the rear end region, Top sheet, Back seat, An absorbent core structure disposed between the top sheet and the back sheet, a. An upper nonwoven fabric layer containing polymer fibers, b. Lower nonwoven fabric layer containing polymer fibers, c. An inner core layer disposed between the upper nonwoven fabric layer and the lower nonwoven fabric layer, comprising cellulose fibers and superabsorbent particles, Absorbent core structure equipped with It comprises at least a flexible coupling channel region formed in the intermediate region, A disposable absorbent article wherein the flexible bond channel region has a dry channel depth of at least 1.0 mm and a channel width of 1.0 mm to 3.0 mm, and the flexible bond channel region has a CD stiffness index of 1.1 to 3.0 and a dry MD stiffness of less than 0.04 N / mm when measured according to the flexible bond channel MD stiffness method.

2. The disposable absorbent article according to claim 1, wherein the dry MD stiffness is 0.005 to 0.035 N / mm when measured according to the flexible bond channel MD stiffness method.

3. The disposable absorbent article according to claim 1, wherein the flexible binding channel region has a minimum channel length of at least 50 mm.

4. The disposable absorbent article according to claim 1, wherein the flexible bonding channel region includes one or more flexible bonding embossments and one or more flexible bonding land regions disposed between each of the flexible bonding embossments.

5. The disposable absorbent article according to claim 4, wherein the thickness of each of the flexible bonding land regions may be 50% to 70% of the thickness of the absorbent article.

6. The disposable absorbent article according to claim 4, wherein the flexible bonding emboss has an embossed area, the flexible bonding channel region has a channel area, and the embossed area is 22% to 65% of the channel area.

7. The disposable absorbent article according to claim 4, wherein the flexible bonding emboss has an embossing length of 1.0 mm to 4.0 mm.

8. The disposable absorbent article according to claim 4, wherein each of the flexible bond land regions has a length of 0.5 mm to 4 mm.

9. The disposable absorbent article according to claim 1, wherein the absorbent article comprises an inner flexible binding channel region and an outer flexible binding channel region.

10. The disposable absorbent article according to claim 1, wherein the absorbent article has an average density of 0.045 g / cm³ to 0.15 g / cm³.

11. The aforementioned flexible binding channel region is 0.05 g / cm³ ３ ~0.3 g / cm ３ A disposable absorbent article according to claim 1, having the channel density.

12. The disposable absorbent article according to claim 1, wherein the upper nonwoven fabric layer has a basis weight of 35 gsm to 85 gsm.

13. The disposable absorbent article according to claim 1, wherein the lower nonwoven fabric layer has a basis weight of 10 gsm to 40 gsm.

14. The disposable absorbent article according to claim 1, wherein the inner core layer comprises 50% to 85% by weight of cellulose fibers and 15% to 50% by weight of superabsorbent particles in the inner core layer.

15. When the absorbent article was measured according to the wet and dry CD and MD three-point bending method, it measured 10 N. ＊ mm² to 30N ＊ A disposable absorbent article according to claim 1, having a CD dry bending stiffness of mm² and a fifth-cycle wet recovery rate of 29% to 40% when measured according to the wet and dry cluster compression method.

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