Absorbent products containing short cellulose fibers

Abstract

A disposable absorbent article has a top sheet, a bottom sheet, and an absorbent core structure disposed therebetween. The absorbent core structure includes an upper nonwoven layer comprising polymer fibers and having a basis weight of about 30 gsm to about 85 gsm; a lower nonwoven layer comprising polymer fibers; and an inner core layer disposed between the upper and lower nonwoven layers. The inner core layer comprises a mixture of cellulose pulp and superabsorbent particles. The cellulose pulp comprises about 25% to about 70% by weight of short cellulose fibers, wherein the short cellulose fibers have an average fiber length of less than about 2 mm. The absorbent core structure has a basis weight of about 0.045 g / cm³. 3 Approximately 0.15 g / cm³ 3 The average density between. By sealing a portion of the first side region and a portion of the second side region of the upper nonwoven layer and the lower nonwoven layer, at least a portion of the inner core layer is contained within the nonwoven layer.

Description

Technical Field

[0001] This invention relates to absorbent articles having short cellulose fibers, and more particularly to absorbent articles containing short cellulose fibers but still providing flexibility, conformability and / or wet integrity during use. Background Technology

[0002] Many consumers of disposable absorbent products, such as feminine hygiene pads, are looking for products made from natural, bio-based, recycled, and / or more environmentally friendly materials. Traditional cellulose sources, such as pine, grow relatively slowly and use significant amounts of water and / or energy in the bovine pulp manufacturing process. In contrast, alternative cellulose sources, such as eucalyptus, paulownia, and bamboo, are known to grow faster and use less water and / or energy in the bovine pulp manufacturing process. Therefore, consumers may perceive these alternative cellulose sources as relatively more sustainable and / or environmentally friendly. However, replacing standard pine cellulose pulp, made from long cellulose fibers (with an average length between 2.5 mm and 6 mm), with short cellulose fibers having an average fiber length of less than approximately 2 mm can present challenges. When short cellulose fibers are used in traditional absorbent core structures, the core can tear and coalesce when wet, negatively impacting product performance. The wet integrity issue of such absorbent core structures is typically addressed by densifying the absorbent core to help reduce core breakage and / or tearing. However, the trade-off for densification is reduced comfort (stiffness) and the ability of the absorbent core structure and / or absorbent fabric to readily conform to the wearer's unique anatomical geometry.

[0003] There is a need to include disposable absorbent articles made of relatively more sustainable and / or environmentally friendly materials that provide flexibility, conformability and / or wet integrity during use. Summary of the Invention

[0004] This document discloses a disposable absorbent article comprising: a top sheet; a bottom sheet; and an absorbent core structure disposed between the top sheet and the bottom sheet. The absorbent core structure comprises: (a) an upper nonwoven layer comprising polymer fibers and having a basis weight of about 30 gsm to about 85 gsm, wherein the upper nonwoven layer includes a first side region and a laterally opposed second side region; (b) a lower nonwoven layer comprising polymer fibers, wherein the lower nonwoven layer includes a first side region and a laterally opposed second side region; and (c) an inner core layer comprising a mixture of cellulose pulp and superabsorbent particles, wherein a portion of the inner core layer is disposed between the upper and lower nonwoven layers. The cellulose pulp comprises about 25% to about 70% short cellulose fibers by weight of the cellulose pulp. The short cellulose fibers have an average fiber length of less than about 2 mm. The absorbent core structure has a fiber length of about 0.045 g / cm³. 3Approximately 0.15 g / cm³ 3 The average density between. This portion of the inner core is contained within the upper and lower nonwoven layers by sealing a portion of the first and second side regions of the upper nonwoven layer with a portion of the first and second side regions of the lower nonwoven layer at the peripheral seal.

[0005] This document also discloses a disposable absorbent article comprising: a top sheet; a bottom sheet; and an absorbent core structure disposed between the top sheet and the bottom sheet. The absorbent core structure comprises: (a) an upper nonwoven layer comprising polymer fibers and having a basis weight of about 30 gsm to about 85 gsm; (b) a lower nonwoven layer comprising polymer fibers and having a basis weight of about 7 gsm to about 40 gsm; and (c) an inner core layer comprising a mixture of cellulose pulp and superabsorbent particles, wherein a portion of the inner core layer is disposed between the upper and lower nonwoven layers. The cellulose pulp comprises cork fibers and about 25% to about 70% short cellulose fibers by weight of the cellulose pulp, wherein the short cellulose fibers have an average fiber length of about 0.3 mm to about 2 mm. The absorbent core structure includes a plurality of structural bonding sites. The structural bonding sites have a thickness of about 2 mm. 2 Approximately 5mm 2 The total structural bonding area of ​​the absorbent core structure is approximately 0.75% to approximately 4.5% of the absorbent core structure, as measured according to the pattern spacing and area measurement method of the structural bonding parts. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the absorber core structure according to this disclosure.

[0007] Figure 2 It is along Figure 1 The cross-sectional view of the absorber core structure taken from line 2-2.

[0008] Figure 3 It is a plan view of the absorbent article, with the surface facing the wearer facing the observer, in which a portion of the structure is cut off to show the construction of the absorbent core structure more clearly;

[0009] Figure 4 It is along Figure 3 The sectional view taken from line 4-4.

[0010] Figure 5 This is a plan view of the absorbent article, with the surface facing the wearer facing the observer. This plan view illustrates an example absorbent core structural arrangement.

[0011] Figure 6A It is along Figure 5A cross-sectional view of the absorbent material taken from line 6A-6A.

[0012] Figure 6B It is along Figure 5 A cross-sectional view of the absorbent material taken from line 6B-6B.

[0013] Figure 7 It is along Figure 5 The sectional view of the absorbent product taken from line 7-7.

[0014] Figure 8 A plan view of an absorbent article, with the wearer-facing surface facing the observer, wherein the top sheet is removed to illustrate an example of the inner core layer and adhesive arrangement.

[0015] Figure 9 This is a close-up illustration of a structural bonding site based on one or more configurations shown and described herein.

[0016] Figure 10 yes Figure 9 A cross-sectional view of the structural bonding area.

[0017] Figure 11A This is a plan view of an example absorbent article according to one or more configurations shown and described herein, with the wearer-facing surface facing the observer, illustrating the flexural bonding channel region.

[0018] Figure 11B This is a plan view of an example absorbent article according to one or more configurations shown and described herein, with the wearer-facing surface facing the observer, illustrating the flexural bonding channel region.

[0019] Figures 12A to 12C It is a test method setup for the wet and dry CD ultra-sensitive 3-point bending method.

[0020] Figure 13 , Figure 14A and Figure 14B This is the test method setup for wet and dry cohesive compression tests.

[0021] Figure 15A and Figure 15B This is an illustrative graph of the coalescence curves generated by wet and dry coalescence compression tests. Figure 15A and Figure 15B The graphs shown are intended to illustrate how the calculations in this method can be performed and do not represent the data described herein. Detailed Implementation

[0022] As used herein, “disposable absorbent articles” or “absorbent articles” should be used in reference to articles such as diapers, training pants, diaper pants, re-fastening pants, adult incontinence pads, adult incontinence pants, feminine hygiene pads, cleaning pads, etc., each of which is intended to be discarded after use.

[0023] As used herein, "absorbent core structure" should be used with reference to the upper nonwoven layer, the lower nonwoven layer, and the inner core layer disposed between the upper and lower nonwoven layers. As used herein, "absorbent core structure" does not include any second top sheet, top sheet, second bottom sheet, or bottom sheet of the absorbent article.

[0024] As used herein, "hydrophilic" and "hydrophobic" have the widely accepted meanings in the art regarding the water contact angle on a material surface. Therefore, a material having a water contact angle greater than about 90 degrees is considered hydrophobic, and a material having a water contact angle less than about 90 degrees is considered hydrophilic. Hydrophobic compositions will increase the water contact angle on a material surface, while hydrophilic compositions will decrease the water contact angle on a material surface. Although described above, references to relative hydrophobicity or hydrophilicity between materials and compositions, 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 may be greater than that of the material. Similarly, 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 may be smaller than that exhibited by the material.

[0025] As used herein, the term "filament" refers to any type of continuous yarn produced by processes such as spinning, meltblowing, melt fibrillation or film fibrillation, electrospinning, or any other suitable process for producing filaments. The term "continuous" in the context of filaments differs from short-length fibers in that short-length fibers are cut to a specific target length. In contrast, "continuous filaments" are not cut to predetermined lengths; instead, they can break into random lengths, but are typically much longer than short-length fibers.

[0026] As used in this article, "longitudinal" refers to the direction in which the fiber web flows through the absorbent material to change the processing direction. For the sake of brevity, the transverse direction can be referred to as "MD".

[0027] As used in this article, "horizontal" refers to the direction perpendicular to the MD. For the sake of brevity, the horizontal direction can be referred to as "CD".

[0028] As used herein, "elastic" means a material that tends to retain its shape in both dry and wet conditions and tends to return to its original shape before compression when subjected to compressive forces and upon removal of such forces. In some respects, the upper and / or lower nonwoven layers described herein may be elastic.

[0029] "Decitex" is a measure used in the textile industry to measure yarn or filament. 1 decitex = 1 gram per 10,000 meters. In other words, if 10,000 linear meters of yarn or filament weighs 500 grams, then the yarn or filament will have 500 decitex.

[0030] As used herein, “wear-facing” (sometimes referred to herein as “body-facing”) and “outward-facing” (sometimes referred to herein as “clothing-facing”) refer to the relative position of an element or the relative position of the surface of an element or group of elements, respectively. “Wear-facing” means that during wear, an element or surface is closer to the wearer than some other elements or surfaces. “Outward-facing” means that during wear, an element or surface is further away from the wearer than some other elements or surfaces (i.e., the element or surface is closer to the wearer’s clothing, which may be worn over an absorbent article).

[0031] It should be understood that each maximum numerical limit given throughout this specification includes each lower numerical limit, as such lower numerical limits are explicitly stated herein. Each minimum numerical limit given throughout this specification will include each higher numerical limit, as such higher numerical limits are explicitly stated herein. Each numerical range given throughout this specification will include each narrower numerical range falling within such a wider numerical range, as all such narrower numerical ranges are explicitly stated herein.

[0032] This disclosure relates to a disposable absorbent article comprising an absorbent core structure including an upper nonwoven layer and a lower nonwoven layer, wherein the inner core layer contains a liquid absorbent material disposed between the upper and lower nonwoven layers. The liquid absorbent material may comprise a homogeneous mixture of cellulose pulp and superabsorbent particles, sometimes referred to herein as “fluff / AGM”. At least a portion of the inner core layer may be contained within the upper and lower nonwoven layers by sealing a portion of a first and second side region of the upper nonwoven layer with a first and second side region of the lower nonwoven layer to define a peripheral seal, wherein an adhesive is positioned between the upper and lower nonwoven layers and bonds the two layers together. In some configurations, the peripheral seal may extend around the entire periphery of the inner core layer.

[0033] The absorbent core structure described herein is constructed to compress and recover its original shape (both wet and dry) under a series of body movements and compressions. The flexibility and / or elasticity of the absorbent core structure allows the absorbent article to comfortably conform to the wearer's anatomical geometry while effectively managing fluid as it leaves the body. This is unexpectedly achieved without the typical densification hardening (for wet integrity) by utilizing elastic upper and lower nonwoven layers composed of elastic polymers above and below a loosely stacked liquid absorbent material located in the inner core layer. Surprisingly, when the absorbent core structure becomes wet, it is able to withstand structural loads and recover its shape without physically hardening or losing the desired structural properties. Without being limited by theory, it is believed that wet integrity / shape stability in cellulose-rich absorbent core structures can be achieved without significant densification and hardening when the selected elastic upper and lower nonwoven layers are positioned above and below the liquid absorbent material in the inner core layer and bonded to and around the liquid absorbent material. Both the upper and lower nonwoven fabrics may possess sufficient restoring energy to bring the liquid absorbent material back to its original or stable fibrous orientation state after compression. Encasing or encapsulating a cellulose-rich core with a simple cellulose structure or a less elastic nonwoven material may not exhibit sufficient restoring energy to recover its shape during use, particularly when wetted. The structural wet-elastic nonwovens detailed herein exhibit sufficient restoring energy to recover the cellulose-rich fibrous matrix after compression and are chosen to deliver high compression recovery with relatively low stiffness in both dry and wet states. It is believed that a suitable absorbent core structure has low compressive force (low resistance) and is able to recover its shape when the user compresses and releases the compressive force in a cyclical manner with various body movements. To achieve this, the structure should maintain sufficient restoring energy after multiple cycles of compression. Without sufficient restoring energy, the structure remains in a compressed, clumped state without sufficient force (stored energy) to recover.

[0034] Surprisingly, the absorbent core structure described herein can comprise a cellulose pulp containing a relatively high level of short cellulose fibers while maintaining structural integrity and conformability without requiring densification of the inner core layer. Short cellulose fibers (such as eucalyptus fibers) in the absorbent core structure exhibit less physical entanglement than longer standard softwood fibers. Therefore, conventional absorbent core structures composed of short cellulose fibers are more prone to cracking and tearing than core structures containing longer cellulose fibers. Without being theoretically limited, it is believed that the elastic upper and / or lower nonwoven layers of the inner core layer described herein can contribute to providing structural integrity to the absorbent core structure and enable the use of short cellulose fibers at a weight of greater than about 25%, or about 25% to about 70%, of the cellulose pulp.

[0035] This article describes an absorbent core structure that sandwiches a liquid absorbent material between two elastic nonwoven layers. These elastic nonwoven layers not only bear and manage the mechanical stresses exerted by the wearer's body during use, but also allow the absorbent core structure to recover its shape when the absorbent article is compressed and deformed during use. The liquid absorbent material may comprise a substantially homogeneous mixture of cellulose pulp and superabsorbent particles. The cellulose pulp may contain approximately 25% to approximately 70% short cellulose fibers. The absorbent core structure may have a density between approximately 0.045 g / cm³. 3 Approximately 0.15 g / cm³ 3 The relatively low average density between them. Without being theoretically limited, it is believed that the density of the entire absorbent core structure described herein allows the cellulose fibers (regardless of fiber length) to move and / or adjust with the wearer's body movements. Once the body force is removed, the upper and / or lower nonwoven layers can help bring the cellulose fibers back to their initial position. In contrast, conventional cellulose core densification essentially locks the cellulose fibers tightly together to reduce the risk of the fibers separating with body movement, which could lead to tearing and / or coalescence. Furthermore, the absorbent core structure described herein (in which the cellulose pulp and superabsorbent particles are substantially homogeneously mixed) is believed to dehydrate fluid from the capillary spaces between the cellulose fibers more quickly (because the core has a low density and therefore less strong capillary forces), and thus resist wet collapse and / or coalescence when the cellulose fibers become saturated with fluid.

[0036] Figure 1 The diagram shows an exemplary absorber core structure 10 of this disclosure. Figure 2 It is along Figure 1 The sectional view taken from line 2-2 shows the structural bonding portion 15 removed to more clearly show the absorbent core structure 10.

[0037] See Figure 1 and Figure 2 The absorbent core structure 10 may include an upper nonwoven layer 210 and a lower nonwoven layer 220 (also collectively referred to herein as upper nonwoven layer and lower nonwoven layer or upper nonwoven fabric and lower nonwoven fabric) and an inner core layer 200 positioned between the upper nonwoven layer 210 and the lower nonwoven layer 220. The absorbent core structure 10 may include the inner core layer 200, which includes a liquid absorbent material. The liquid absorbent material may comprise a homogeneous mixture of cellulose pulp and superabsorbent particles. A portion of the upper nonwoven layer 210 and the lower nonwoven layer 220 may be joined together at a peripheral seal 230.

[0038] Figure 3 The exemplary absorbent article 20 of this disclosure is shown in the figure. For the purpose of providing a frame of reference for this discussion, Figure 3The absorbent article 20 is shown having a longitudinal axis 80 and a transverse axis 90. Figure 3 This is a plan view of the absorbent article 20, with the wearer-facing surface 112 facing the observer, where a portion of the structure is cut off to more clearly show the construction of the absorbent core structure 10. Figure 4 It is along Figure 3 A cross-sectional view of absorbent product 20 taken from line 4-4.

[0039] See Figures 3 to 4 The absorbent article 20 may include a top sheet 110, a bottom sheet 130, and an absorbent core structure 10 disposed between the top sheet 110 and the bottom sheet 130. The absorbent article 20 may include a wearer-facing surface 112 and a garment-facing surface 132. The absorbent article 20 and the absorbent core structure 10 each include a front region 21, a rear region 23, and a central region 22 disposed between the front region 21 and the rear region 23. In some configurations, the absorbent core structure 10 may have a non-rectangular perimeter. Specifically, the absorbent core may be shaped to define a cone shape along its width toward the central region of the absorbent core structure. The absorbent core structure may be adapted to the geometry of the wearer's inner thigh, such as, for example, an hourglass shape, an offset hourglass shape (one end is wider than the opposite end and has a narrowing middle section between the two ends), a bicycle seat shape (one end and the central portion are narrower than the second end), an ellipse, or a trapezoid.

[0040] In some configurations, the disposable absorbent article 20 may include the following structure (from the wearer-facing surface to the outward-facing surface): a top sheet 110, an upper nonwoven layer 210, an inner core layer 200, a lower nonwoven layer 220, and a back sheet 130. In some aspects, the top sheet 110 may be in direct contact with the upper nonwoven layer 210, the upper nonwoven layer 210 may be in direct contact with the inner core layer 200, and / or the inner core layer 200 may be in direct contact with the lower nonwoven layer 220. "Direct contact" means that there is no additional intermediate component layer between the respective layers in direct contact. However, it is not excluded that an adhesive material may be disposed between at least a portion of the aforementioned layers.

[0041] The upper nonwoven layer 210 may include a first side region 210a and a laterally opposite second side region 210b, and the lower nonwoven layer 220 may include a first side region 220a and an opposite second side region 220b. In some configurations, the first side regions 210a of the upper and lower nonwoven layers may extend substantially parallel to the longitudinal axis 80. The upper and lower nonwoven layers 210 and 220 may extend outward from the inner core periphery 200a and may be bonded together by adhesive or other conventional bonding methods to form a peripheral seal 230, including but not limited to ultrasonic bonding, fusion bonding, crimping, and combinations thereof. In some configurations, the entire inner core 200 may be located inside the peripheral seal 230. The peripheral seal 230 may help seal the liquid-absorbing material of the inner core 200 within the upper and lower nonwoven layers 210 and 220. The peripheral seal 230 may include a first sealing region 231 extending at least substantially parallel to the longitudinal centerline 80 and a second sealing region 231' opposite to the first sealing region 231. In some configurations, the peripheral seal 230 may also include a front peripheral sealing region 232 and / or a rear peripheral sealing region 233. In some configurations, the peripheral seal 230 may extend around the entire inner core periphery 200a.

[0042] Unrestricted by theory, it is believed that when attached to the inner core layer by applying a core-construction adhesive, which is applied directly to the inner core layer or via conventional spray application selected to achieve bonding without interrupting fluid flow to the inner core layer, the elastic nonwoven layer can maintain its shape and resist plasticization upon wetting. The core-construction adhesive is applied to the elastic nonwoven layer either directly to the inner core layer or via conventional spray application, which is chosen to achieve bonding without interrupting fluid flow to the inner core layer. A peripheral seal 230 may be positioned in at least a central region 22 of the absorbent article 20 and / or absorbent core structure 10. The central region 22 (located between the wearer's thighs during use) is believed to be subjected to the most frequent and / or greatest forces during use. It has been found that the presence of at least partial peripheral seals in the first and second side regions of the upper and lower nonwoven layers outside the inner core layer can help ensure that the upper and lower nonwoven layers maintain their structural function without separation during physical deformation, thereby limiting any potential integrity and gathering problems. In addition, the peripheral seals allow any excess nonwoven material to be removed so that the absorbent core structure can be shaped to conform to the geometry of the inner thigh.

[0043] The peripheral seal 230 may have a seal width WS between about 1 mm and about 10 mm, or between about 2 mm and about 8 mm, or between about 3 mm and about 6 mm. The seal width WS may be uniform or may vary around the periphery of the inner core layer.

[0044] In some configurations, the upper nonwoven layer 210 and the lower nonwoven layer 220 can be discrete materials that can be cut to approximately the size and shape of the inner core layer 200 for attachment between the top sheet 110 and the bottom sheet 130. In some configurations, the inner core layer 200, the upper nonwoven layer 210, and / or the lower nonwoven layer 220 can be shaped, meaning they are non-rectangular.

[0045] In some configurations, the absorber core structure may not include a peripheral seal. In some configurations, the peripheral seal 230 may extend partially around the periphery 200a of the inner core layer. Figures 5 to 8 An absorbent article with an exemplary arrangement of absorbent core structures is shown. Figures 5 to 8 The above references Figures 1 to 4 The elements with the same reference numerals may be the same elements (e.g., inner core layer 200). Figure 6A It is along Figure 5 A cross-sectional view of the absorbent material taken from line 6A-6A. Figure 6B It is along Figure 5 A cross-sectional view of the absorbent material taken from line 6B-6B. Figure 7 It is along Figure 5 The sectional view of the absorbent product taken from line 7-7.

[0046] refer to Figures 5 to 7 In some configurations, the upper nonwoven layer 210 may extend longitudinally between the front edge 403 and the rear edge 404, defining a first side region 210a and a laterally opposite second side region 210b. The lower nonwoven layer 220 may extend longitudinally between the front edge 408 and the rear edge 409, defining a first side region 220a and a laterally opposite second side region 220b. The upper nonwoven layer 210 may have a first nonwoven lateral width WN1, and the lower nonwoven layer 220 may have a second nonwoven lateral width WN2. In some configurations, the first nonwoven lateral width WN1 and the second nonwoven lateral width WN2 may be substantially the same. In some configurations, the first nonwoven lateral width WN1 and the second nonwoven lateral width WN2 may be different. The first nonwoven transverse width WN1 and / or the second nonwoven transverse width WN2 may be from about 40 mm to about 110 mm, or from 45 mm to about 90 mm, or from about 50 mm to about 80 mm. The upper nonwoven layer 210 and / or the lower nonwoven layer 220 may have a longitudinal length from about 100 mm to about 450 mm, or from about 150 mm to about 375 mm. In some configurations, the upper nonwoven layer 210 and / or the lower nonwoven layer 220 may extend from the front article edge 30 to the rear article edge 32.

[0047] At least a portion of the inner core layer 200 may be disposed between the upper nonwoven layer 210 and the lower nonwoven layer 220. In some configurations, the entire inner core layer 200 may be disposed between the upper nonwoven layer 210 and the lower nonwoven layer 220.

[0048] The inner core layer 200 extends longitudinally between its front edge 424 and rear edge 426, and laterally from its first side edge 250 to its second side edge 252. In some configurations, the inner core layer 200 may be shaped as follows: Figure 8 As shown, the inner core layer 200 may define a first inner core layer lateral width WC1, a second inner core layer lateral width WC2, and a third inner core layer lateral width WC3 disposed therebetween. In some configurations, the first inner core layer lateral width WC1 may be located in the front region 21 and the second inner core layer lateral width WC2 may be located in the rear region 23. In some configurations, the third inner core layer lateral width WC3 may be smaller than the first inner core layer lateral width WC1 and the second inner core layer lateral width WC2. In some configurations, the second inner core layer lateral width WC2 may be larger than the first inner core layer lateral width WC1 and the third inner core layer lateral width WC3. The first inner core layer lateral width WC1 may be approximately 50 mm to approximately 80 mm, the second inner core layer lateral width WC2 may be approximately 55 mm to approximately 100 mm, and the third inner core layer lateral width WC3 may be approximately 40 mm to approximately 70 mm.

[0049] An adhesive region 525 may be disposed between at least one of the upper nonwoven layer 210 and the lower nonwoven layer 220 and the inner core layer 200. The adhesive region 525 may contain an adhesive 528 extending from a first side region 210a of the upper nonwoven layer 210 to a second side region 210b of the upper nonwoven layer 210 and / or from a first side region 220a of the lower nonwoven layer 220 to a second side region 220b of the lower nonwoven layer 220. Figure 8 As shown, the adhesive region 525 may extend from the first edge 525a to the second edge 525b to define a lateral width WZ of the adhesive region of about 35 mm to about 110 mm or about 40 mm to about 105 mm. In some configurations, the first edge 525a and the second edge 525b of the adhesive region 525 may be adjacent to or laterally spaced from the lateral edges of the upper nonwoven layer 210 and / or the lower nonwoven layer 220. In some configurations, such as Figure 5As shown, the gap region 530 can be defined on the upper nonwoven layer 210 and / or the lower nonwoven layer 220 by the absence of adhesive 528 between the first edge 525a and the second edge 525b of the adhesive region 525 and the edge of the nonwoven fabric. The gap region 530 may have a width of about 5 mm or less, or about 0.1 mm to about 5 mm, or about 0.5 mm to about 3 mm. In some configurations, the upper nonwoven layer 210 and the lower nonwoven layer 220 may substantially surround the adhesive region 525 and the inner core layer 200.

[0050] In some configurations, a portion of the inner core layer 200 may be included within the upper nonwoven layer 210 and the lower nonwoven layer 220 by sealing a portion of a first side region 210a and a portion of a second side region 210b of the upper nonwoven layer 210 with a portion of a first side region 220a and a portion of a second side region 220b of the lower nonwoven layer 220 to define a lateral peripheral seal 230, wherein an adhesive 528 is positioned between the upper nonwoven layer 210 and the lower nonwoven layer 220. Thus, the adhesive 528 can bond the upper nonwoven layer 210 to the lower nonwoven layer 220. The lateral peripheral seal 230 may be positioned in the intermediate region 22 and may have a longitudinal seal length LS, which is approximately 45% to approximately 90%, or approximately 50% to approximately 85% of the longitudinal inner core length LC.

[0051] refer to Figure 5 A portion of the inner core layer 200 may extend laterally outside the adhesive region 525 to define an unsealed portion 420. The unsealed portion 420 may be longitudinally positioned outside the peripheral seal 230. It should be understood that the absorbent core structure 10 may include one or more unsealed portions 420, such as, for example, two, three, or four unsealed portions, depending on the size and / or positioning of the upper and lower nonwoven layers relative to the adhesive region and the inner core layer.

[0052] The absorbent core structure 10 may include a first unsealed portion 423a, wherein a portion of the inner core layer 200 extends laterally outside the adhesive region 525. In some configurations, the absorbent core structure 10 may include a second unsealed portion 423b, wherein a second portion of the inner core layer 200 extends laterally outside the adhesive region 525. The second unsealed portion 423b may be laterally separated from the first unsealed portion 423a by a sealing portion 410. In some configurations, the first unsealed portion 423a and the second unsealed portion 423b may be positioned in a rear region 23 and may extend longitudinally into a portion of an intermediate region 22. The absorbent core structure 10 may also include a third unsealed portion 421a, wherein a third portion of the inner core layer 200 extends laterally outside the adhesive region 525. In some configurations, the absorbent core structure 10 may include a fourth unsealed portion 421b, wherein a fourth portion of the inner core layer 200 extends laterally outside the adhesive region 525. The fourth unsealed portion 421b can be laterally separated from the third unsealed portion 421a via the sealing portion 410. In some configurations, the third unsealed portion 421a and the fourth unsealed portion 421b may be positioned in the front region 21 and may extend longitudinally into the middle region 22. It should be understood that the unsealed portion 420 may also be configured such that a portion of the inner core periphery 200a is adjacent to the first edge 525a or the second edge 525b of the adhesive region 525.

[0053] The first unsealed portion 423a and the second unsealed portion 423b may have an unsealed longitudinal length L1U, which is about 5% to about 30%, or about 8% to about 25% of the longitudinal inner core length LC. The third unsealed portion 421a and the fourth unsealed portion 421b may have an unsealed longitudinal length L2U, which is about 5% to about 30%, or about 8% to about 25% of the longitudinal inner core length LC. In some configurations, the unsealed longitudinal length L1U of the first unsealed portion 423a or the second unsealed portion 423b may be greater than the unsealed longitudinal length L2U of the third unsealed portion 421a or the fourth unsealed portion 421b.

[0054] Figure 6A and Figure 6B These are cuts taken along lines 6A-6A and 6B-6B respectively. Figure 5 A cross-sectional view of the absorbent article 20, showing the configuration of the absorbent core structure 10. Specifically, Figure 6AThe cross-sectional view through the middle region 22 of the absorbent article 20 shows the upper nonwoven layer 210 and the lower nonwoven layer 220 extending laterally outside the first side edge 250 and the second side edge 252 of the inner core layer 200. As discussed above, a portion of the inner core layer 200 can be included within the upper nonwoven layer 210 and the lower nonwoven layer 220 by sealing a portion of the first side region 210a and the second side region 210b of the upper nonwoven layer 210 with a portion of the first side region 220a and the second side region 220b of the lower nonwoven layer 220 to define a lateral peripheral seal 230. Figure 6B This is a cross-sectional view through the rear region 23 of the absorbent article 20, showing the upper nonwoven layer 210 and the lower nonwoven layer 220 extending laterally outside the first side edge 250 and the second side edge 252 of the inner core layer 200. As discussed above, a portion of the inner core layer 200 may extend laterally outside the adhesive area 525 (not shown) to define an unsealed portion 420. It should be understood that the garment-facing surface of the upper nonwoven layer 210 and / or the wearer-facing surface of the lower nonwoven layer 220 may be coated with adhesive 528 to provide a connection with the inner core layer 200 and / or form a peripheral seal 230. For simplicity, in Figure 6A and Figure 6B The adhesive between the layers is not shown (except in the peripheral seal).

[0055] As previously mentioned, the upper nonwoven layer 210 and the lower nonwoven layer 220 may further engage at a front peripheral sealing region 232 and / or a rear peripheral sealing region 233 longitudinally positioned outside the inner core layer 200. The front peripheral sealing region 232 and / or the rear peripheral sealing region 233 may extend longitudinally from the inner core layer periphery 200a by a distance of approximately 3 mm to approximately 30 mm, or approximately 5 mm to approximately 15 mm. Without theoretical limitations, it is believed that a front peripheral sealing region 232 and / or a rear peripheral sealing region 233 less than approximately 3 mm may not provide sufficient distance on the manufacturing line to avoid contaminating the liquid-absorbing material outside the inner core layer. In some configurations, the front peripheral sealing region 232 may be adjacent to or longitudinally spaced from the front edge 403 of the upper nonwoven layer 210 and / or the front edge 406 of the lower nonwoven layer 220. In some configurations, the rear peripheral seal 233 may be adjacent to or longitudinally spaced from the rear edge 404 of the upper nonwoven layer 210 and / or the rear edge 409 of the lower nonwoven layer 220.

[0056] In some configurations, the lateral width WC1 of the first inner core layer and the adhesive area width WZ may be substantially the same, resulting in an unsealed portion where the adhesive 528 does not extend laterally beyond the outer side of the inner core layer perimeter 200a, and the upper nonwoven layer 210 is not bonded to the lower nonwoven layer 220 in this region. It should be understood that in some configurations, the lateral width WC2 of the second inner core layer may be substantially the same as the adhesive area width WZ, thus defining the unsealed portion in the rear region 23. In some configurations, the lateral width WC1 of the first inner core layer may be smaller than the adhesive area width WZ. The upper nonwoven layer 210 and the lower nonwoven layer 220, along with the adhesive area 525, may substantially surround the inner core layer in the front region, and the lateral peripheral seal 230 may extend longitudinally from the intermediate region 22 into the front region 21. In this configuration, the inner core layer is sealed within the upper nonwoven layer 210 and the lower nonwoven layer 220 in the intermediate region 22 and the front region 21. It should be understood that in some configurations, the lateral width WC2 of the second inner core layer may be smaller than the width WZ of the adhesive region, thus creating a lateral peripheral seal 230 that extends longitudinally from the middle region 22 to the rear region 23.

[0057] In some configurations, at least one of the upper nonwoven layer 210 and the lower nonwoven layer 220 may be narrower than at least a portion of the inner core layer. In some configurations, the upper nonwoven layer 210 and / or the lower nonwoven layer 220 may be narrower than the lateral width WC1 of the first inner core layer and / or the lateral width WC2 of the second inner core layer.

[0058] See Figure 5 and Figure 7 The leading edge 403 of the upper nonwoven layer 210 and / or the leading edge 408 of the lower nonwoven layer 220 may be adjacent to or longitudinally spaced from the leading edge 30 of the front article. In some configurations, the trailing edge 404 of the upper nonwoven layer 210 and / or the trailing edge 409 of the lower nonwoven layer 220 may be adjacent to or longitudinally spaced from the trailing edge 32 of the rear article. The absorbent article 20 may also include a coiled seal 500 positioned in the front region 21 and / or the rear region 23. In some configurations, the coiled seal 500 may extend from the front region 21 and / or the rear region 23 into the intermediate region 22. In some configurations, the coiled seal 500 may be longitudinally positioned outside the front peripheral seal 232 and the rear peripheral seal 233. In some configurations, the front peripheral seal region 232 and the rear peripheral seal region 233 may extend into the coiled seal 500.

[0059] The coil seal 500 can engage at least one of the top sheet 110, the bottom sheet 130, and the upper nonwoven layer 210 and the lower nonwoven layer 220. In some configurations, the coil seal 500 can engage the top sheet 110 with the bottom sheet 130. Surprisingly, the coil seal 500 can include the upper nonwoven layer 210 and / or the lower nonwoven layer 220 without becoming stiff or uncomfortable. The coil seal 500 may be substantially free of liquid-absorbing material.

[0060] refer to Figure 3 The absorbent article 20 may also include a base structure 100, which includes an absorbent core structure 10. The absorbent core structure 10 and / or inner core layer 200 may be shaped. The sides 120 and 125 of the absorbent article 20 may follow the general outline of the absorbent core structure 10 and / or inner core layer 200. Thus, for example, in the case where the absorbent core structure 10 has an hourglass shape, the sides 120, 125 of the absorbent article 20 may also be arranged in an hourglass shape. However, it is contemplated that the sides 120 and 125 are generally straight or slightly curved such that they do not follow the outline of the absorbent core structure. In some configurations, the absorbent article 20 may be symmetrical or asymmetrical about the longitudinal centerline 80. Similarly, the absorbent article 20 may be symmetrical or asymmetrical about the transverse centerline 90.

[0061] In some configurations, such as Figure 1 , Figure 9 and Figure 10 As shown, the absorbent article and / or absorbent core structure may include multiple structural bonding sites 15. Figure 9 and Figure 10 An example of the bonding portion 15 of the example structure is shown. Figure 9 This is a close-up illustration of the bonding portion 15 of the example structure. Figure 10 yes Figure 9 A cross-sectional view of the structural bonding portion 15. The structural bonding portion 15 can be symmetrical and / or asymmetrical, and can be of any shape, including but not limited to circular, elliptical, heart-shaped, rhomboid, triangular, square, star-shaped, and / or X-shaped. While the shape of the structural bonding portion 15 can be any shape, suitable shapes can be more detailed, such as asymmetrical shapes (as opposed to simple points). The structural bonding portion 15 can be on the absorbent article and / or on the absorbent core structure. In some configurations, the structural bonding portion can have approximately 2 mm. 2 Approximately 5mm 2The total structural bond area may be from about 0.5% to about 7.5%, or about 0.75% to about 5%, or about 1% to about 4% of the absorbent core structure, as measured by methods for measuring the pattern spacing and area of ​​the structural bonded parts. In some configurations, the total structural bond area may be from about 1% to about 4% of the absorbent article, as measured by methods for measuring the pattern spacing and area of ​​the structural bonded parts. The average distance between structural bonded parts may be from about 10 mm to about 32 mm. In some configurations, the average distance between structural bonded parts may be greater than about 20 mm. In some configurations, the structural bonded parts may have a maximum width of from about 1 mm to about 6 mm, or from about 1.5 mm to about 5 mm, or from about 2 mm to about 4 mm. Without being theoretically limited, it is believed that the average distance between structural bonded parts and / or the size of the structural bonded parts can help maintain the structural integrity of the absorbent core structure without producing undesirable stiffness that could inhibit the absorbent article's ability to conform to the body.

[0062] In some configurations, structural bonding areas may be distributed across the absorbent article and / or absorbent core structure, or they may be clustered within regions of the absorbent article and / or absorbent core structure. In some configurations, structural bonding areas may be clustered in the intermediate region 22 of the absorbent article and / or absorbent core structure. In some configurations, the intermediate region 22 of the absorbent article and / or absorbent core structure may have no structural bonding areas and may be surrounded by the area of ​​structural bonding areas and / or embossing.

[0063] In some configurations, the structural bonding portion 15 may bond the top sheet 110, the upper nonwoven layer 210, the absorbent core structure 10, and the lower nonwoven layer 220. The absorbent article 20 and / or the absorbent core structure 10 may include the upper nonwoven layer 210 and the lower nonwoven layer 220, which are brought closer together in the Z-direction at the structural bonding portion 15, but are not fused together. Because these structural bonding portions are not fused together, they may not be permanent in nature, but may become entangled with the material within the structural bonding portion. In some configurations, the structural bonding portion 15 may be substantially unbonded.

[0064] like Figure 11A and Figure 11B As shown, the absorbent article may also include one or more flexural bonding channel regions 160, wherein these flexural bonding channel regions may be continuous recesses and / or a series of individually compressed, closely spaced embossings.

[0065] A suitable upper nonwoven layer may have a basis weight of about 30 gsm to about 85 gsm, or about 35 gsm to about 70 gsm, or about 40 gsm to about 60 gsm. The upper nonwoven layer may have a tensile stiffness of about 0.1 N / mm to about 2.2 N / mm, or about 0.3 N / mm to about 1.6 N / mm, as measured by the CD cyclic elongation to 3% strain method. The upper nonwoven layer may have a fracture strain greater than about 10%, or about 10% to about 50%, or about 20% to about 40%, as measured by the fracture strain method. The upper nonwoven layer may have a permanent strain of about 0.005 mm / mm to about 0.013 mm / mm, or 0.005 mm / mm to about 0.0090 mm / mm, as measured by the CD cyclic elongation to 3% strain method.

[0066] A suitable underlayer nonwoven may have a basis weight of about 7 gsm to about 40 gsm, or about 10 gsm to about 35 gsm, or about 15 gsm to about 20 gsm. The underlayer nonwoven may have a tensile stiffness of about 0.2 N / mm to about 1.6 N / mm, as measured by the CD cyclic elongation to 3% strain method. The underlayer nonwoven may have a fracture strain greater than about 10%, or about 10% to about 50%, or about 20% to about 40%, as measured by the fracture strain method. The underlayer nonwoven may have a permanent strain of about 0.005 mm / mm to about 0.013 mm / mm, as measured by the CD cyclic elongation to 3% strain method.

[0067] The upper and / or lower nonwoven layers may comprise polymer fibers. Suitable upper and lower nonwoven fibers may be selected from PET (polyethylene terephthalate), PP (polypropylene), BiCo (bicomponent fibers) selected from PE / PP (PE sheath / PP core) and / or PE / PET (PE sheath / PET core), PLA (polylactic acid), and combinations thereof. In some configurations, the upper and / or lower nonwoven layers may comprise recycled polymer resins, biodegradable polymers, biopolymers, bio-based fibers, and combinations thereof.

[0068] Suitable upper nonwoven fabrics may contain about 60% to about 100%, or about 70% to about 100% synthetic fibers, or about 0% to about 40%, or about 0% to about 30% regenerated cellulose fibers, such as rayon and / or viscose fibers.

[0069] The upper nonwoven layer may comprise short fibers with lengths greater than about 10 mm, or greater than about 25 mm, or from about 10 mm to about 100 mm, or from about 20 mm to about 75 mm, or from about 25 mm to about 50 mm. The upper nonwoven layer may comprise fibers with diameters from about 1.3 dtex to about 10.0 dtex, alternatively from about 1.3 dtex to about 6.0 dtex, or alternatively from about 2.0 dtex to about 5.0 dtex. Without theoretical limitations, it is believed that if the fibers in the upper nonwoven layer are smaller than about 1.3 dtex, there may not be sufficient airflow through the material during manufacturing.

[0070] In some configurations, the upper nonwoven layer may comprise a blend of short fibers. When the upper nonwoven layer comprises a blend of short fibers, the fiber blend preferably comprises 30% or less of fibers with a fiber diameter of 1.3 dtex and / or 30% or less of fibers with a fiber diameter of 10.0 dtex. In some configurations, the upper nonwoven layer may comprise fibers, wherein the fibers are a blend of short fibers with an average fiber diameter of about 2.0 dtex to about 8.0 dtex. Without being theoretically limited, it is believed that fibers with an average fiber diameter of about 2.0 dtex to about 8.0 dtex will help to allow sufficient airflow through the material during the manufacture of the absorbent core structure.

[0071] The lower nonwoven layer may comprise short fibers with a length greater than about 10 mm, or greater than about 25 mm, or about 10 mm to about 100 mm, or about 20 mm to about 75 mm, or about 25 mm to about 50 mm. In some configurations, the lower nonwoven layer may comprise continuous fibers. The lower nonwoven layer may comprise fibers with a fiber diameter of about 1.0 dtex to about 5.0 dtex, or about 1.3 dtex to about 3.3 dtex, or about 1.3 dtex to about 2.2 dtex, or about 2.0 dtex to about 10.0 dtex. In some configurations, the lower nonwoven layer may comprise fibers, wherein the fibers are a blend of fibers with a fiber diameter of about 0.1 dtex to about 6.0 dtex.

[0072] In some configurations, the upper nonwoven layer may comprise a blend of fibers, wherein at least a portion of the fibers have a diameter of about 2.0 dtex to about 10.0 dtex, and the lower nonwoven layer may comprise a blend of fibers, wherein at least a portion of the fibers have a diameter of about 1.3 dtex to about 5.0 dtex. In some configurations, the upper nonwoven layer may comprise a blend of fibers, wherein at least a portion of the fibers have a diameter of about 1.3 dtex to about 2.2 dtex, and the lower nonwoven layer may comprise a blend of fibers, wherein the blend of fibers has a diameter of about 1.0 dtex to about 5.0 dtex.

[0073] Suitable upper and / or lower nonwoven materials can bend under bending force and substantially recover their original shape. Thin or highly flexible materials bend easily under low peak force (load) and low bending energy. Unsuitable materials, while easily bent, lack sufficient recovery energy and therefore remain deformed in a bent state due to insufficient recovery energy. Suitable materials have sufficient energy to substantially recover their initial pre-bent state. Materials with sufficient bending recovery energy can be considered as elastic upper and lower nonwoven layers. Particularly suitable upper nonwoven layers can have a strength greater than about 0.03 N. mm, or approximately 0.03N mm to approximately 1N mm, or approximately 0.04N mm to approximately 0.5N The dry recovery energy is mm. A particularly suitable upper nonwoven layer can have less than about 1.6 N. mm, or less than about 1.1N mm of dry bending energy.

[0074] As described above, the upper and lower nonwoven fabrics may include polymer fibers. Polymer fibers may be included to help provide structural integrity of the upper and lower nonwoven fabrics. Polymer fibers can help improve the structural integrity of the upper and lower nonwoven layers in both the longitudinal (MD) and transverse (CD) directions, which can facilitate web manipulation during the processing of the upper and lower nonwoven fabrics to incorporate them into the padding.

[0075] Polymer fibers with any suitable composition can be selected. Some examples of suitable polymer fibers may include bicomponent fibers comprising polyethylene (PE) and polyethylene terephthalate (PET) components, or polyethylene terephthalate and co-ethylene terephthalate components. The components of the bicomponent fibers can be configured in a sheath-core configuration, a side-by-side configuration, an eccentric sheath-core configuration, a trefoil arrangement, or any other desired configuration. In some configurations, the polymer fibers may include bicomponent fibers having a PE / PET composition configured in a concentric sheath-core configuration, wherein the polyethylene component forms the sheath.

[0076] While other materials may be useful in forming elastic structures, the stiffness of the PET core component in a sheath-core fiber configuration is believed to be useful in imparting elasticity to both the upper and lower nonwoven fabrics. In synergistic combinations, the PE sheath component, having a lower melt temperature than the PET core component, can be used to provide interfiber melt / fusion bonding, achieved via heat treatment of the precursor pad. This can contribute to providing tensile strength to the web on both the MD and CD. This interfiber bonding can be used to reduce fiber-to-fiber slippage, thereby further contributing to imparting shape stability and elasticity to the material, even when the material is wetted.

[0077] With a relatively high weight fraction of polymer fibers, more connections can be created within the structure via heat treatment. However, too many connections can impart greater stiffness to the upper and lower nonwoven fabrics than desired. For this reason, selecting the weight fraction of polymer fibers may involve prioritizing and balancing the competing needs for stiffness and flexibility in the upper and lower nonwoven fabrics.

[0078] As described above, the upper and lower nonwoven fabrics may additionally include polymer fibers, which increase the elasticity of the upper and lower nonwoven fabrics. The elastic polymer fibers help the upper and lower nonwoven layers maintain permeability and compression recovery. In some configurations, the upper and lower nonwoven layers may include elastic polymer fibers with variable cross-sections (e.g., circular and hollow helical), and / or may include elastic fibers of different sizes.

[0079] The polymer fibers can be elastic and can be spun from any suitable thermoplastic resin, such as polypropylene (PP), polyethylene terephthalate (PET), or other suitable thermoplastics known in the art. The elastic polymer fibers can have any suitable structure or shape. For example, the elastic polymer fibers can be circular or have other shapes, such as spiral, fan-shaped elliptical, trefoil, fan-shaped band, etc. Furthermore, the elastic polymer fibers can be solid, hollow, or multi-hollow. The elastic polymer fibers can be solid and circular in shape. In other suitable examples, the elastic polymer fibers include polyester / co-extruded polyester fibers. In one specific example, the PET fibers can have a hollow cross-section and a curved or spiral configuration along their length. Optionally, the elastic polymer fibers can be helical or flat-curled. The elastic polymer fibers can have an average crimp count of about 4 to about 12 crimps per inch (cpi), or about 4 cpi to about 8 cpi, or about 5 cpi to about 7 cpi, or about 9 cpi to about 10 cpi. Specific, non-limiting examples of elastic polymer fibers are available from Wellman, Inc. (Ireland) under the trade names H1311 and T5974. Other examples of suitable elastic polymer fibers are disclosed in US 7,767,598.

[0080] Careful selection of reinforcing and elastic polymer fibers is essential. For example, while the constituent polymers forming the reinforcing and elastic polymer fibers may be similar, the elastic polymer fiber composition should be selected such that the melting temperature of its components is higher than that of the bondable component of the reinforcing polymer fiber. Otherwise, during heat treatment, the elastic polymer fiber may bond to the reinforcing polymer fiber, and vice versa, resulting in an overly rigid structure. To avoid this risk, the reinforcing polymer fiber may comprise a bicomponent fiber, such as a core-sheath configuration fiber with a sheath component having a relatively low melting temperature at which fusion bonding will occur, while the elastic polymer fiber may consist only of the constituent chemical composition of the core, which may be a polymer with a relatively high melting temperature.

[0081] Nonwoven properties can be influenced by a combination of the choice of nonwoven fiber polymer, fiber characteristics, and fiber arrangement or connection. Nonwoven selection can affect the ability of an absorbent article to recover its shape after being subjected to compressive, bending, and stretching (tensile) forces during use and with body movement. If the fibers are short (less than about 10 mm), they may irreversibly rearrange under stretching and compressive forces. This rearrangement of fibers within the fiber matrix (changing their orientation / state) dissipates the stretching (elongation) or compressive forces, making the energy used to influence deformation no longer available to restore the original shape. Longer fiber networks (typically greater than about 10 mm but less than about 100 mm) can absorb typical stretching / compressive forces along the fiber length and through the structure during body movement. Therefore, the absorbed forces can be used to restore the structure to its original state. Longer fiber networks composed of finer fibers (typically less than about 15 micrometers to about 20 micrometers) are more prone to stretching and compression. Therefore, the pile / AGM structure can deform more easily (and to a greater degree), but the energy associated with these deformations is relatively small and insufficient to bring the structure back to its original state. Coarser fibers (such as those larger than about 20 micrometers or 2.0 dtex to about 10 dtex) are flexible under physical forces, but provide enough fiber and web recovery energy to return the structure to its original state.

[0082] From a structural perspective, the fiber arrangement in a long fiber network can affect the properties of absorbent articles containing these nonwovens. Long fiber webs with thicker fibers are generally more bulky than conventional thin spunbond nonwoven webs composed of closely spaced and physically bonded continuous fine fibers. Webs that produce thicker fibers arranged in a more random orientation (such as those that can be achieved through carding, hydroentangling, and needle punching) are able to stretch and compress, whereby the fibers only temporarily adjust their alignment (for which there are spaces between the fibers) and are able to bear / store deformation forces, and this energy can be used to restore the structural shape.

[0083] Additionally, the finer (less than about 2.0 dBre) synthetic fibers (such as BiCo and PP fibers) typically found in spunbonds are closely spaced, relatively parallel, and tightly bonded together. The interconnection of these bonding fibers within the spunbond web (using closely spaced point bonding) forces the polymer-level fibers to stretch during tension (elongation), resulting in a permanent rearrangement of the polymer chains within the fibers. Consequently, the fibers themselves may retain permanent elongation (permanent strain) and can no longer return to their initial state.

[0084] In some configurations, the polymer fibers in the upper nonwoven layer and the polymer fibers in the lower nonwoven layer can be different. In some configurations, the polymer fibers in the upper nonwoven layer and the polymer fibers in the lower nonwoven layer can be the same. In some configurations, the upper nonwoven layer can be a carded nonwoven fabric. In some configurations, the upper nonwoven layer can be air-through bonded, needle-punched, carded, or hydroentangled. In some configurations, the upper nonwoven layer is not a spunbond material.

[0085] Suitable examples of nonwoven materials may include, but are not limited to, the following: (i) a 40 gsm carded elastic nonwoven material (material code; ATB Z87G-40-90) manufactured by Yanjan China, which is a carded nonwoven composed of a blend of 60% 2 dtex and 40% 4 dtex BiCo (PE / PET) fibers. The fibers are bonded (ATB = bonded by “hot” air) to create a wet elastic network. The material basis weight is 40 gsm and its thickness (at 7 kPa) is approximately 0.9 mm. Without being theoretically limited, it is believed that due to the presence of the 4 dtex BiCo fibers and the fiber-to-fiber bonded BiCo network, this material exhibits low permanent strain (less than approximately 0.013 mm / mm) and sufficient dry recovery energy (greater than approximately 0.03 N) in both wet and dry CD ultrasensitive 3-point bending tests. (ii) A 55gsm elastic jet-spun web material (material code: 53FC041001) manufactured by Sandler Germany, which is a hydroentangled nonwoven fabric produced by a carding step (as described above for nonwoven fabrics) followed by an elevated drying step (as described in U.S. Patent Publication No. 2020 / 0315873A1), which produces an entangled and BiCo-bonded elastic network. It comprises a blend of 30% 10dtex HS-PET, 50% 2.2dtex BiCo (PE / PET), and 20% 1.3dtex rayon fibers. Therefore, in wet and dry CD ultrasensitive 3-point bending tests, this material exhibits low permanent strain (less than about 0.013 mm / mm) and sufficient dry recovery energy (greater than about 0.03 N). (iii) a 50 gsm elastic jet-spun web material (material code: 53FC041005 opt82) manufactured by Sandler Germany, which is a spunlace nonwoven fabric produced via a carding step (as described above for nonwoven fabrics) followed by an elevated drying step (as described in U.S. Patent Publication No. 2020 / 0315873A1), which produces an entangled and BiCo-bonded elastic network. It comprises a blend of 60% 5.8 dtex BiCo (PE / PET), 20% 3.3 dtex trefoil "structural" rayon, and 20% 1.3 dtex rayon. Therefore, in wet and dry CD ultrasensitive 3-point bending, this material exhibits low permanent strain (less than about 0.013 mm / mm) and sufficient dry recovery energy (greater than about 0.03 N). (mm). Although the material contains 40% rayon that softens when wet, the use of structural trilobal rayon fibers contributes to structural stability in the wetted state.

[0086] By adjusting pore size, volume, and quantity through the selection of appropriate fiber size, basis weight, and degree of consolidation, manufacturers may wish to select fiber compositions with specific surface chemistry properties, such as fibers with hydrophobic surfaces, hydrophilic surfaces, or blends of different fibers and / or their z-direction layering or gradients. Fibers with hydrophilic surfaces will tend to attract and move the aqueous components of menstrual fluid in a manner that facilitates rapid fluid collection after wicking and expulsion. However, the advantage of hydrophilic fiber surfaces within the topsheet may simultaneously increase the topsheet's tendency to re-absorb fluid from the underlying absorbent assembly (rewetting), potentially leading to an undesirable wetting sensation for the user. On the other hand, fibers with hydrophobic surfaces will tend to repel the aqueous components of menstrual fluid and / or resist fluid movement along their surface, thus tending to resist wicking but also resisting rewetting. For any given product design, a manufacturer may seek an appropriate balance in selecting constituent fibers with hydrophilic surfaces, fibers with hydrophobic surfaces, or blends thereof and / or z-direction layering, combining fiber size, fiber consolidation level, and the resulting top sheet pore size, volume, and number.

[0087] The inner core layer is produced in an airflow web-forming process. A stream of cellulose pulp and superabsorbent particles is carried on a rapidly moving airflow and deposited into a three-dimensionally shaped pocket on a rotary forming drum, which has a vacuum below to draw the cellulose pulp and superabsorbent particles into the pocket in a settling station. This pocket shape provides the actual physical shape of the absorbent core structure. An upper or lower nonwoven fabric can be first introduced onto the forming drum and drawn into a three-dimensional pocket shape under vacuum. In this case, the cellulose pulp and superabsorbent particle material stream is deposited directly onto the upper (or lower) nonwoven fabric in the forming station. Before entering the forming station, the nonwoven fabric is coated with an adhesive to provide a stronger bond between the cellulose and superabsorbent polymer and the nonwoven layer. Particularly suitable adhesives may include high wet strength adhesives, such as Technomelt DM9036U, available from Henkel (Germany). Upon exiting the resting section, the second remaining nonwoven layer combines with the nonwoven material carrying the cellulose pulp and superabsorbent particle layer. This second remaining nonwoven material (either the upper or lower nonwoven material, depending on which type travels through the resting section) is pre-coated with an adhesive to achieve a peripheral seal and better integrate the cellulose pulp and superabsorbent particles without impeding liquid flow into the cellulose pulp and superabsorbent particle matrix. In another method, instead of first introducing the nonwoven material into the molding station, the cellulose pulp and superabsorbent particle clumps are held on the molding drum under vacuum until they are sprayed onto the upper or lower nonwoven layer with the adhesive applied as detailed above, and then sealed with the second remaining nonwoven material to create an absorbent core structure. The widths of the upper and lower nonwoven webs are typically chosen to be wider than the maximum width of the shaped cellulose pulp and the superabsorbent particle matrix, in order to achieve an effective peripheral seal at the junction of the two nonwovens, at least on the leftmost and rightmost sides of the absorbent core structure.

[0088] The inner core layer can contain any of the various liquid absorbent materials commonly used in absorbent articles, such as pulverized wood pulp (often referred to as breathable felt). A suitable core material is breathable felt material available under code FR516 from Weyerhaeuser Company (Washington, USA). Examples of other suitable liquid absorbent materials that can be used in the core may include crepe cellulose filler; including co-formed meltblown polymers; chemically hardened, modified, or cross-linked cellulose fibers; synthetic fibers such as crimped polyester fibers; peat moss; cotton; absorbent polymer materials; or any equivalent material or combination of materials, or mixtures thereof.

[0089] In some configurations, the liquid absorbent material may comprise a substantially homogeneous mixture of cellulose pulp and superabsorbent particles. The cellulose pulp may comprise short cellulose fibers. As used herein, "short cellulose fiber" means a cellulose fiber having an average fiber length of less than about 2 mm, or from about 0.3 mm to about 2 mm, or from about 0.5 mm to about 1.5 mm. As used herein, fiber length is defined as "length-weighted average fiber length". The fiber length distribution can be determined according to ISO 16065-2 (2014). In some configurations, the short cellulose fibers may be obtained from hardwood pulp sources such as maple, oak, eucalyptus, poplar, beech, birch, paulownia, and mixtures thereof; non-wood fiber sources such as bamboo, industrial hemp fiber, acacia, wheat straw, rice straw, corn husks, and mixtures thereof; and combinations of hardwood pulp sources and non-wood fiber sources. In some configurations, short cellulose fibers can be obtained by chemical pulping (such as cowhide pulping) and / or mechanical pulping (such as, for example, chemithermomechanical pulping, stone mill pulping, and / or pressure pulping). In some configurations, the short cellulose fibers may have an average fiber diameter of about 0.01 mm to about 0.04 mm.

[0090] In some configurations, the cellulose pulp may comprise about 25% to about 70%, or about 30% to about 65%, or about 35% to about 60%, or about 40% to about 55%, or about 45% to about 50% of short cellulose fibers by weight of the cellulose pulp, specifically including all 1% increments within the ranges listed above and all ranges formed therein or thereby. In some configurations, the cellulose pulp may comprise about 25% to about 100%, or about 30% to about 90%, or about 50% to about 75% of short cellulose fibers by weight of the cellulose pulp, specifically including all 1% increments within the ranges listed above and all ranges formed therein or thereby. In some configurations, the cellulose pulp may comprise about 25% to about 50%, or about 30% to about 40% of short cellulose fibers by weight of the cellulose pulp, specifically including all 1% increments within the ranges listed above and all ranges formed therein or thereby.

[0091] In some configurations, the cellulose pulp may contain cork fibers. As used herein, “cork fiber” refers to fibers obtained from cork pulp sources such as pine, fir, spruce, cedar, and combinations thereof. In some configurations, the cork fibers may have an average fiber length of about 2.5 mm to about 6 mm. The cellulose pulp may contain about 30% to about 75%, or about 35% to about 70%, or about 40% to about 65% cork fibers by weight of the cellulose pulp, specifically listing all 1% increments within the above ranges and all ranges formed therein or thereby.

[0092] In some configurations, the inner core may contain a ratio of short cellulose fibers to superabsorbent particles of about 0.2 to about 4.5, or about 0.5 to about 1.5.

[0093] In some configurations, multiple cellulose fibers in the inner core layer can penetrate the lower surface of the upper nonwoven layer. Without being theoretically limited, it is believed that the penetration of multiple cellulose fibers into the lower surface of the upper nonwoven layer and / or the entanglement of cellulose fibers with the polymer fibers of the upper nonwoven layer can lead to improved mechanical stability between the upper nonwoven layer and the inner core layer, and can contribute to providing improved fluid transport from the upper nonwoven layer to the inner core layer for storage.

[0094] Absorbent polymer materials used in absorbent articles typically include water-insoluble, water-swellable, hydrogel-forming crosslinked absorbent polymers that can absorb large amounts of liquid and retain such absorbed liquid under moderate pressure.

[0095] The absorbent polymer material used in the absorbent core according to this disclosure may include superabsorbent particles, also known as “superabsorbent material” or “absorbent gel material.” The absorbent polymer material (typically in particulate form) may be selected from polyacrylates and polyacrylate-based materials, such as, for example, partially neutralized, cross-linked polyacrylates. The term “particle” refers to granules, fibers, flakes, spheres, powders, sheets, and other shapes and forms known to those skilled in the art of superabsorbent particles. In some aspects, superabsorbent particles may be in the shape of fibers, i.e., elongated needle-like superabsorbent particles.

[0096] In some configurations, the core layer may comprise about 50% to 85%, or about 55% to about 80%, or about 60% to about 75% of cellulose pulp by weight of the core layer. The core layer may comprise about 15% to about 50%, or about 20% to about 50%, or about 25% to about 40%, or about 30% to about 35% of superabsorbent particles by weight of the core layer. In some configurations, the core layer may comprise about 125 gsm to about 350 gsm of cellulose pulp. In some configurations, the core layer may comprise about 20 gsm to about 125 gsm of superabsorbent particles.

[0097] In some configurations, the inner core layer may comprise approximately 50% to approximately 85% cellulose pulp and approximately 15% to approximately 50% superabsorbent particles. The absorbent core structure may have a density between approximately 0.045 g / cm³. 3 Approximately 0.15 g / cm³ 3 Between, and / or between 0.045 g / cm 3 and 0.12g / cm 3 The average density is between [0.045 g / cm³]. Absorbent products may have an average density between [0.045 g / cm³]. 3 Approximately 0.16 g / cm³3 The average density between.

[0098] Following the compression step, the absorbent core structures can be compressed and return to their original shape. A suitable absorbent core structure requires low compressive force (low resistance) and is able to return to its shape as the user compresses and releases the compressive force in a cyclical manner with various body movements. To achieve this, the structure maintains sufficient restorative energy after multiple cycles of compression. Without sufficient restorative energy, the structure remains in a compressed, lumped state, lacking sufficient force (stored energy) to recover.

[0099] The absorbent article 20 can be elastic and conformable, delivering an excellent user experience without significantly bunching and / or compression. The absorbent article can be exposed to physical forces and can substantially return to its original state. The absorbent article may have a strength between approximately 0.07 N / mm². 2 and 0.30 N / mm 2 Between, or approximately 0.10 N / mm 2 To approximately 0.25 N / mm 2 or approximately 0.10 N / mm 2 To approximately 0.20 N / mm 2 The dry modulus of CD, as measured in wet and dry CD and MD 3-point bending method.

[0100] The absorbent article may have a dry thickness between about 2.0 mm and about 6.0 mm, or about 2.0 mm to about 4.5 mm, or about 2.5 mm to about 4.0 mm, as measured by the wet and dry CD and MD 3-point method. In some configurations, the absorbent article may have a thickness between about 0.07 N / mm. 2 and 0.30 N / mm 2 The CD dry modulus and dry thickness are between approximately 2.0 mm and approximately 4.5 mm, as measured by the 3-point method for wet and dry CDs and MDs, or between approximately 0.10 N / mm. 2 To approximately 0.25 N / mm 2 The dry modulus of CD and the dry thickness are between approximately 2.5 mm and approximately 4.0 mm. The absorbent article may have a dry modulus between approximately 7.0 N. mm 2 To approximately 30.0N mm 2 or approximately 10.0N mm 2 Approximately 25.0N mm 2 or approximately 10.0N mm 2 To approximately 20.0N mm 2or approximately 13.0N mm 2 To approximately 20.0N mm 2 The dry bending stiffness of CD between wet and dry CD and MD is measured in the 3-point bending method.

[0101] The absorbent article may have approximately 1.0 N. mm to 3.5N mm, or approximately 1.5N mm to approximately 3.0N mm, or approximately 1.5N mm to approximately 2.8N The fifth cycle wet recovery energy is mm. Particularly suitable absorbent materials may have an energy between approximately 1.0 N. mm and 3.5N The fifth cycle wet recovery energy is between mm and approximately 29% to 40% of the fifth cycle wet recovery.

[0102] Absorbent articles, including those with absorbent core structures as disclosed herein, may also need to deliver a dry feel to the consumer after the addition of fluid, as measured by a touch-rewetting method. Absorbent core structures and absorbent articles that meet the above characteristics are designed to comfortably and gently conform more closely and completely to the complex anatomical shape of the wearer's genitals. Therefore, such absorbent articles may also need to feel dry to the touch after excretion in order not to irritate sensitive genital tissues. Consequently, the absorbent articles described herein may also maintain a touch-rewetting value of less than about 0.15 grams, or less than about 0.12 grams, or about 0 grams to about 0.15 grams, or about 0 grams to about 0.12 grams.

[0103] Top film

[0104] The top sheet 110 can be formed from any suitable nonwoven web or molded film material. Referring back to the accompanying drawings, the top sheet 110 is positioned adjacent to the wearer-facing surface of the absorbent article 20 and can be joined thereto and to the bottom sheet 130 by any suitable attachment or adhesive method. The top sheet 110 and the bottom sheet 130 can be directly joined to each other in the outer peripheral region outside the periphery of the absorbent core structure, and can also be indirectly joined by directly joining them to the wearer-facing and outward-facing surfaces of the absorbent article, respectively, or by including additional optional layers in the absorbent article.

[0105] The absorbent article 20 may have any topsheet 110 known to be otherwise effective, such as a soft, gentle-feeling topsheet that is non-irritating to the wearer's skin. Suitable topsheet materials will include liquid-permeable materials that are comfortable in contact with the wearer's skin and allow the expelled menstrual fluid to permeate quickly. Some suitable examples of topsheet materials include membranes, nonwovens, and laminated structures having membrane / nonwoven layers, membrane / membrane layers, and nonwoven / nonwoven layers.

[0106] Non-limiting examples of nonwoven fiber web materials that may be used as top sheet 110 include fibrous materials made of natural fibers, modified natural fibers, synthetic fibers, or combinations thereof. Some suitable examples are described in U.S. Patent Nos. 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.

[0107] Topsheet 110 may be soft, comfortable to the touch, and non-irritating to the wearer's skin. Furthermore, topsheet 110 may be liquid-permeable, allowing liquids (e.g., urine, menstrual fluid) to easily pass through its thickness. Some suitable examples of topsheet materials include membranes, nonwovens, and laminated structures having membrane / nonwoven layers, membrane / membrane layers, and nonwoven / nonwoven layers. Other exemplary topsheet materials and designs are disclosed in U.S. Patent Application Publications 2016 / 0129661, 2016 / 0167334, and 2016 / 0278986.

[0108] In some examples, topsheet 110 may include clusters, as described in US 8,728,049, US 7,553,532, US 7,172,801, US 8,440,286, US 7,648,752, and US 7,410,683. Topsheet 20 may have a pattern of discrete, hair-like fibrils as described in US 7,655,176 or US 7,402,723. Additional examples of suitable topsheet materials include those described in US 8,614,365, US 8,704,036, US 6,025,535, and US Patent Publication No. 2015 / 041640. Another suitable topsheet may be formed from a three-dimensional substrate, as detailed in US 2017 / 0258647. The top sheet may have one or more layers, as described in U.S. Patent Publications 2016 / 0167334, 2016 / 0166443, and 2017 / 0258651.

[0109] In some examples, the top sheet 110 may be formed of a nonwoven web material of a spunbond web, which includes monocomponent continuous fibers, or alternatively, bicomponent or multicomponent fibers, or blends of monocomponent fibers spun from different polymer resins, or any combination thereof. The top sheet may also be a shaped nonwoven top sheet, as disclosed in U.S. Patent Publication No. 2019 / 0380887.

[0110] To ensure that fluid contacting the top (wearer-facing) surface of the topsheet moves appropriately and rapidly in the z-direction to the bottom (outer-facing) surface of the topsheet, where it can be drawn into the absorbent article, it is important that the nonwoven web material forming the topsheet has an appropriate weight / volume density, reflecting the proper presence of interstitial channels (sometimes called "pores") within and between the constituent fibers through which fluid can move within the nonwoven material. In some cases, nonwoven materials with excessively densely bound fibers may have insufficient number and / or volume and / or size of pores, and the nonwoven material will obstruct rather than facilitate rapid downward fluid movement in the z-direction. On the other hand, nonwoven materials with fibers that are too large and / or insufficiently bound to provide a degree of opacity (for the purpose of concealing the absorbed fluid in the underlying layers) and a striking appearance may be negatively perceived by the user.

[0111] The thickness of the topsheet material can be controlled to balance the competing demands for opacity and bulk (which require higher thickness) with the limitation on the z-direction distance that the discharged fluid travels from the wearer-facing surface through the topsheet to the outward-facing surface to reach the underlying absorbent core structure. Therefore, it may be desirable to control the manufacture of the topsheet material to produce a thickness of about 0.20 mm to about 1.0 mm, or about 0.25 mm to about 0.80 mm, or about 0.30 mm to about 0.60 mm.

[0112] In some configurations, the absorbent article may not include a discrete top sheet, and the upper nonwoven layer may be used as the top sheet.

[0113] Second Top Plate (STS)

[0114] In some cases, the STS layer can be included between the top sheet and the absorber core structure so that the absorber core structure can easily receive a sudden discharge of fluid and, after receiving it, wick the fluid along the x and y directions to distribute the fluid onto the absorber core structure below.

[0115] If included, the STS can be a nonwoven fibrous structure, which may include cellulose fibers, non-cellulose fibers (e.g., fibers spun from polymer resins), or blends thereof. To accommodate the folding and lateral aggregation of the absorbent article 20 and the absorbent core structure 10, as described herein, the STS can be formed of a relatively flexible material (i.e., having relatively low flexural stiffness).

[0116] Suitable STS compositions and structures, and numerous specific examples of their combinations with suitable topsheet compositions and structures, are further described in U.S. Patent Serials 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 Application Serials 63 / 086,610 and 63 / 086,701. Additional suitable examples are described in US 9,504,613; WO 2012 / 040315; and US 2019 / 0021917.

[0117] In some configurations, the absorbent article may not contain a second top sheet.

[0118] negative

[0119] The film 130 can be positioned below or near the outward-facing surface of the absorbent core structure 10 and can be bonded thereto by any suitable attachment method. For example, the film 130 can be secured to the absorbent core structure 10 by a uniform, continuous layer of adhesive, a patterned layer of adhesive, or an array of adhesive separation lines, spirals, or dots. Alternatively, the attachment method may include thermal bonding, pressure bonding, ultrasonic bonding, dynamic mechanical bonding, or any other suitable attachment mechanism or combination thereof. In other examples, it is conceivable that the absorbent core structure 10 is not directly bonded to the film 130.

[0120] The film 130 may be impermeable or substantially impermeable to aqueous liquids (e.g., urine, menstrual fluid) and may be made of a thin plastic film, although other liquid-impermeable flexible materials may also be used. As used herein, the term "flexible" refers to a material that is compliant and readily conforms to the general shape and contours of the human body. The film 130 may prevent or at least substantially inhibit the escape of fluids absorbed and contained within the absorbent core structure 10 from reaching clothing articles, such as underwear and outerwear, that may come into contact with the absorbent article 20. However, in some cases, the film 130 may be made and / or adapted to allow vapors to escape from the absorbent core structure 10 (i.e., the film is made breathable), while in other cases, the film 130 may be made so as not to allow vapors to escape (i.e., it is made impermeable). Thus, the film 130 may comprise a polymer film, such as a thermoplastic film of polyethylene or polypropylene. Suitable materials for the film 130 are, for example, thermoplastic films with a thickness of about 0.012 mm (0.5 mils) to about 0.051 mm (2.0 mils). Any suitable film known in the art can be used in this invention.

[0121] Suitable examples of materials suitable for forming film are described in US 5,885,265, US 4,342,314, and US 4,463,045. Suitable single-layer breathable films for use herein include, for example, those described in GB A 2184 389, GB A 2184 390, GB A 2184 391, US 4,591,523, US 3,989,867, US 3,156,242, WO 97 / 24097, US 6,623,464, US 6,664,439, and US 6,436,508.

[0122] Film 130 may have two layers: a first layer comprising a vapor-permeable pore-formed membrane layer and a second layer comprising a breathable microporous membrane layer, as described in US 6,462,251. Other suitable examples of bilayer or multilayer breathable films used herein include those described in US 3,881,489, US 4,341,216, US 4,713,068, US 4,818,600, EP 203821, EP 710 471, EP 710 472 and EP 0 793 952.

[0123] Other features

[0124] In some configurations, absorbent article 20 may include underwear fastening components, such as underwear fastening adhesives or hook-and-loop fastening systems (such as VELCRO). ® ) components.

[0125] In some configurations, the absorbent article 20 may be provided with a panty-fastening adhesive disposed on the garment-facing side of the backing 130 to provide a mechanism for the user to adhere the absorbent article to the inside of the user's underwear in its crotch area. The panty-fastening adhesive may include any adhesive or glue in the art used for such purposes. These adhesives are typically pressure-sensitive and remain tacky well below their application temperature. In some configurations, the panty-fastening adhesive may be a pressure-sensitive hot melt adhesive. The panty-fastening adhesive may be applied in a pattern (such as that described in U.S. Patent Publication No. 2020 / 0281782A1). When the absorbent article 20 is packaged for transport, handling, and storage prior to use, the panty-fastening adhesive may be covered with a protective cover (not shown), such as silicone-coated release paper, silicone-coated plastic film, or any other easily removable cover. The protective cover may be provided as a single piece or in multiple pieces, for example, to cover individual adhesive areas (such as on the backing and / or on the wings). The protective cover covers / masks adhesive deposits to prevent them from contacting other surfaces until the user is ready to remove the protective cover and place the absorbent article in the user's underwear for wear / use. The protective cover can also serve as personalized packaging for the article or provide disposal functionality as known in the art. Any commercially available release paper or film can be used. Suitable examples include BL 30 MG-A SILOX EI / O and BL 30 MG-A SILOX 4 P / O from Akrosil, and M&W film from Gronau (Germany) under code X-5432. In some configurations, the absorbent article may be packaged in a bi-fold or tri-fold configuration.

[0126] In some configurations, the absorbent article 20 may include opposing wing portions 140, 150 on each side, the wing portions extending laterally beyond the longitudinal edge of the absorbent portion of the absorbent article, with a width dimension relatively larger than the width dimension of the front and rear portions of the absorbent article. Wings are currently commonly provided on feminine hygiene absorbent articles. As provided, they typically have an adhesive deposit applied to their outward-facing surface (which is outward-facing before the absorbent article is placed inside the user's underwear and the wings are applied). The wings may also include the adhesive deposit described above, which allows the user to wrap the wings around the inner edge of the leg opening of the underwear and adhere the wings to the outward-facing surface / underside of the underwear in the crotch area, thereby providing supplemental retaining support for the absorbent article and helping to protect the underwear near its leg edges from soiling.

[0127] Packaging

[0128] The absorbent articles disclosed herein can be placed in a package. The package may include a polymer film, paper, and / or other materials. Graphics and / or markings relating to the characteristics of the absorbent articles may be formed on, printed on, positioned on, and / or placed on the outer portion of the package. Each package may include multiple absorbent articles. The absorbent articles can be stacked under compression to reduce the size of the package while still providing a sufficient amount of absorbent article per package. By packaging absorbent articles under compression, users and caregivers can easily handle and store the packages, especially in bathrooms and other space-constrained areas, while also providing distribution savings for manufacturers due to the size of the packages. The package may include a polymer film comprising recycled materials, such as about 20% to about 100%, about 30% to about 90%, about 30% to about 80%, about 40% to about 60%, or about 50% recycled materials. The recycled materials may include post-industrial recycled materials (PIR) and / or post-consumer recycled materials (PCR). In some cases, the polymer film used for encapsulation may include two outer layers and one or more inner layers. The one or more inner layers may include recycled materials or may contain more recycled materials than the outer layers. Recycled materials may include recycled polyethylene. Recycled materials may include trimmed recycled polyethylene PIR from packaging operations.

[0129] Packaging materials may include paper, paper-based materials, paper with one or more barrier layers, or paper / film composites. Packaging materials may range from about 50 gsm to about 100 gsm or from about 70 gsm to about 90 gsm, and the one or more barrier layers may range from about 3 gsm to about 15 gsm. Paper-based packaging materials, with or without one or more barrier layers, may exhibit a longitudinal tensile strength of at least 5.0 kN / m, a longitudinal tensile strength of at least 3%, a transverse tensile strength of at least 3 kN / m, and a transverse tensile strength at break of at least 4%, each determined according to ISO 1924-3.

[0130] Paper-based packaging materials, or paper-based packaging materials including barrier layers or films, may be recyclable or recyclable in normal paper recycling operations. The degree of recyclability of paper-based packaging can be determined by a recyclability percentage. The paper-based packaging of this disclosure may exhibit a recyclability percentage of 70% or greater, 80% or greater, or 90% or greater. The paper-based packaging of this disclosure may have a recyclability percentage between 70% and about 99.9%, between about 80% and about 99.9%, or between about 90% and about 99.9%. In one example, the paper-based packaging of this disclosure may exhibit a recyclability percentage of about 95% to about 99.9%, about 97% to about 99.9%, or at most about 98% to about 99.9%. The percentage of recyclable paper-based packaging can be determined via test PTS-RH:021 / 97 (draft October 2019) under Category II, as conducted by PapiertechnischeStiftung located at Pirnaer Strasse 37, 01809 Heidenau, Germany. In another case, the paper-based packaging of this disclosure can exhibit an overall "pass" test result, as determined by PTS-RH:021 / 97 (draft October 2019) under the Category II method. Any paper-based packaging may have opening features, such as perforated lines, and may also have a handle.

[0131] Test methods

[0132] The layer of concern

[0133] For any of the following methods for all component layers of the article that are not tested, the layer of interest may be separated from the untested layers using cryo-spray as needed.

[0134] Fracture strain method

[0135] The force-displacement behavior of the samples was measured on a universal constant-rate elongation test frame equipped with a load sensor (suitable instrument being an MTS Alliance instrument using TestSuite software, purchased from MTS Systems Corp., Eden Prairie, MN, or equivalent), with the measured force within 1% to 99% of the load sensor's limits. The samples were stretched at a constant rate (mm / sec) until fracture, and the percentage of fracture strain was measured. All tests were conducted in a room controlled at 23°C ± 3°C and 50% ± 2% relative humidity, with the test samples conditioned in this environment for at least 2 hours prior to testing.

[0136] The clamps used to hold the test specimens are lightweight (<80 grams), vise-like clamps with a semi-cylindrical steel gripping surface at least 40 mm wide and rubber-coated steel. The clamps are mounted on a universal test frame and are installed such that they are aligned horizontally and vertically with each other.

[0137] Test specimens taken from raw material rolls or sheets, or from material layers removed from absorbent articles, are measured. When removing material layers from absorbent articles, care is taken to avoid contaminating or deforming the layer during the process. The removed layer should be free of residual adhesive and any fibers that may have transferred from the underlying layer. To ensure the removal of all adhesive and any transferred fibers, the layer is immersed in a suitable solvent that will dissolve the adhesive and release any transferred fibers present without adversely affecting the material itself. One such solvent is THF (tetrahydrofuran, CAS 109-99-9, for general purposes, available from any readily available source). After solvent immersion, the material layer is allowed to air dry thoroughly to prevent excessive stretching or other deformation of the material. After the material has dried, test specimens are prepared as follows: Test specimens are cut from an area of ​​the test material that is free of any creases or wrinkles. 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 a similar manner.

[0138] Prepare the general test frame as follows. Set the initial clamp-to-clamp spacing to a nominal gauge length of 80 mm, then zero the clamps. Program the test frame to move the clamps closer together with an intentional 1 mm relaxation to ensure no preload on the test specimen at the start of the test. (During this movement, the specimen will become relaxed between the clamps.) Next, the clamps will be moved away at a relaxation rate of 1 mm / s until a relaxation preload of 0.05 N is exceeded. (At this point, the clamp position signal is used to calculate the sample relaxation, adjusted gauge length, and strain is capped at zero, 0.0). The clamps will then be moved away at a rate of 1 mm / s until the sample breaks or exceeds the instrument's extension limit.

[0139] The test specimen is inserted into the clamp so that its long axis is parallel to and centered with the movement of the clamp. The test begins and force (“load”) and displacement data are continuously collected at a data acquisition rate of 100 Hz.

[0140] Plot a load (N) versus displacement (mm) curve. Determine the peak load from the curve, and then determine the fracture sensitivity as follows. After reaching the peak load, determine the clamp position where the load signal decreases by 75%, and record this as the final specimen length (Lf), accurate to 0.01 mm. The initial specimen length is defined by the clamp position when a relaxation preload of more than 0.05 N is applied, and this value is recorded as the initial specimen length (Li), accurate to 0.01 mm. Calculate the percentage of fracture strain as follows, and record it, accurate to 1%.

[0141] % Fracture strain = ((Lf–Li) / Li) 100

[0142] Repeat the procedure for all five repeated test specimens in a similar manner. Calculate the arithmetic mean of the fracture strain % for the five repeated test specimens and report it as fracture strain %, accurate to 1%.

[0143] Wet and dry CD and MD 3-point bending method

[0144] The flexural properties of the absorbent article test samples were measured on a universal constant-speed extension test frame equipped with a load sensor (suitable instrument being the MTS Alliance using TestSuite software, purchased from MTS Systems Corp., Eden Prairie, MN, or equivalent), with the measured force within 1% to 99% of the load sensor's limits. The test was performed on both dry and wet test specimens. The intent of this method is to simulate the deformation in the xy-plane produced by the wearer of the absorbent article during normal use. All tests were performed in a room controlled at 23°C ± 3°C and 50% ± 2% relative humidity.

[0145] The bottom clamp consists of two cylindrical rods, each 3.175 mm in diameter and 110 mm in length, made of polished stainless steel. Each rod has frictionless roller bearings at both ends. These two rods are horizontally mounted, aligned front to back, and parallel to each other. The top radii of the rods are vertically aligned and allow free rotation about the diameter of the cylinder via the frictionless bearings. Furthermore, the clamp allows the two rods to move horizontally away from each other on a track, enabling the establishment of a gap between them while maintaining their orientation. The top clamp consists of a third cylindrical rod, also made of polished stainless steel, with a diameter of 3.175 mm and a length of 110 mm, and frictionless roller bearings at both ends. When in the proper position, the rods of the top clamp are parallel to and aligned front to back with the rods of the bottom clamp, and centered between the rods of the bottom clamp. Both clamps include an integrated adapter adapted for mounting in the appropriate position on a universal test frame and locking in place such that the movement of the rods is orthogonal to the movement of the test frame crossbeam.

[0146] Set the gap (“span”) between the bars of the lower clamp to 25mm ± 0.5mm (center to center of bar), with the upper bar centered at the midpoint between the lower bars. Set the gauge length (bottom of the top bar to top of the lower bar) to 1.0cm.

[0147] The thickness (“caliper”) of the test specimen is measured using a manually operated micrometer equipped with a pressure foot capable of applying a stable pressure of 0.1 psi ± 0.01 psi. This manually operated micrometer is a heavy-duty instrument with readings accurate to 0.01 mm. A suitable instrument is the Mitutoyo Series 543ID-C Digimatic, or equivalent, purchased from VWR International. The pressure foot is a flat, circular, movable surface with a diameter not exceeding 25.4 mm. The test specimen is supported by a horizontal, flat reference platform, which is larger than and parallel to the surface of the pressure foot. The micrometer is zeroed against the horizontal, flat reference platform. The test specimen is placed on the platform, centered below the pressure foot. The pressure foot is lowered manually at a rate of 3 ± 1 mm / s until the full weight of the pressure is applied to the specimen. After 5 seconds, the thickness is recorded as the caliper, accurate to 0.01 mm.

[0148] Prepare the test fluid for measuring wet test samples by adding 100.0 g of sodium chloride (reagent grade, any convenient source) to 900 g of deionized water in a 1 L Erlenmeyer flask. Stir until the sodium chloride is completely dissolved.

[0149] Prior to testing, absorbent sample specimens were conditioned for two hours at 23℃±3℃ and 50%±2% relative humidity. Dry test specimens were taken from a sample area free of any seams, creases, or wrinkles, ideally from the center of the absorbent (the intersection of the longitudinal and transverse centerlines). Dry specimens were prepared for MD (longitudinal) bending by cutting them 50.8 mm wide along CD (transverse; parallel to the transverse axis of the sample) and 50.8 mm long along MD (parallel to the longitudinal axis of the sample), maintaining their orientation after cutting, and marking the body-facing surface (or the surface intended to face the finished product). Dry specimens were also prepared for CD (longitudinal) bending by cutting them 50.8 mm wide along MD (transverse; parallel to the transverse axis of the sample) and 50.8 mm long along CD (parallel to the longitudinal axis of the sample), maintaining their orientation after cutting, and marking the body-facing surface (or the surface intended to face the finished product). As described in this article, the thickness of the test specimen was measured and recorded as the dry specimen thickness, accurate to 0.01 mm. Now, the mass of the test specimen was measured and recorded as the dry mass, accurate to 0.001 g. This was calculated by dividing the mass (g) by the area (0.002581 m²). 2 The basis weight of the sample is calculated and recorded as the dry sample basis weight, accurate to 0.01 g / m³. 2 By measuring the sample basis weight (g / m³) 2 Divide the sample thickness (mm) by the quotient, then divide the quotient by 1000 to calculate the bulk density of the sample, and record it as the dry sample density, accurate to 0.01 g / cm³. 3 Five repeat dry test specimens were prepared in a similar manner. The absorber core was removed, separating it from the rest of the specimen. The thickness of the absorber core was measured as described herein and recorded as the dry absorber core thickness, accurate to 0.01 mm. The mass of the absorber core was now measured and recorded as the dry mass, accurate to 0.001 g. This was calculated by dividing the mass (g) by the area (0.002581 m²). 2 The basis weight of the absorber core is calculated and recorded as the dry absorber core basis weight, accurate to 0.01 g / m³. 2 By measuring the absorption core weight (g / m³) 2 Divide the quotient by the absorber core thickness (mm), then divide the quotient by 1000 to calculate the average density of the absorber core structure, and record it as the dry absorber core density, accurate to 0.01 g / cm³. 3 In a similar manner, five repeatable dry test absorber cores were prepared.

[0150] The wet test specimen was initially prepared in the exact same manner as the dry test specimen, with the test fluid added just before testing, as described below. First, the thickness and mass of the dry specimen were measured as described herein and recorded as the initial thickness (accurate to 0.01 mm) and initial mass (accurate to 0.001 g). Next, the dry specimen was completely immersed in the test fluid for 60 seconds. After 60 seconds, the specimen was removed from the test fluid and held vertically for 30 seconds to allow any excess fluid to drip off. As described herein, the thickness and mass of the wet specimen were now measured and recorded as the wet specimen thickness (accurate to 0.01 mm) and wet specimen mass (accurate to 0.001 g). If necessary, the mass of the test fluid in the test specimen was calculated by subtracting the initial mass (g) from the wet specimen mass (g) and recording it as the test specimen fluid volume (accurate to 0.001 g). The test must be performed within 10 minutes after the wet test specimen is removed from the test fluid. Five replicate wet test specimens were prepared in a similar manner.

[0151] The general-purpose test frame used for the flexural bending test was programmed to move the clamps such that the top clamp moved downward relative to the lower clamp at a rate of 1.0 mm / s until the upper rod contacted the top surface of the specimen with a nominal force of 0.02 N, and then continued for another 12 mm. The clamps were then immediately returned to the original gauge length at a rate of 1.0 mm / s. Force (N) and displacement (mm) data were continuously collected at 100 Hz throughout the test.

[0152] Load the dry test specimen so that it spans the two bottom bars and is centered below the top bar, with its sides parallel to the bars. For MD bending, the MD direction of the test specimen is perpendicular to the length of the three bars. Begin the test and continuously collect force and displacement data.

[0153] Plot the force (N) versus displacement (mm). Determine the maximum peak force from the graph and record it as the dry MD peak load, accurate to 0.01 N. Now calculate and record the maximum slope of the curve between the initial force and the maximum force (during the loading portion of the curve), accurate to 0.1 units. Calculate the modulus as follows and record it as the dry MD modulus, accurate to 0.001 N / mm. 2 .

[0154] CD or MD Dry or wet flexural modulus (N / mm) 2 = (slope × (span)) 3 )) / (4×sample width×(sample thickness) 3 ))

[0155] The bending stiffness is calculated as follows and recorded as dry MD bending stiffness, accurate to 0.1 N / mm. 2 .

[0156] CD or MD Dry or wet bending stiffness (N mm) 2 = Modulus × Moment of Inertia

[0157] Wherein the moment of inertia (mm) 4 = (sample width × (sample thickness)) 3 )) / 12

[0158] The procedure was repeated for all five replicate dry test specimens in a similar manner. For each parameter in the parameters, the arithmetic mean of the five replicate dry test specimens was calculated and reported as the dry specimen “thickness” (accurate to 0.01 mm) and the dry specimen basis weight (accurate to 0.01 g / m³). 2 ), dry sample density (accurate to 0.001 g / cm³) 3 Peak load of dry CD or MD (accurate to 0.01N), flexural modulus of dry CD or MD (accurate to 0.001N / mm). 2 ) and dry CD or MD bending stiffness (accurate to N mm) 2 ).

[0159] Now, repeat the entire procedure for all five replicates of the wet test specimens, and report the results as wet CD or MD peak load (accurate to 0.01 N) and wet CD or MD flexural modulus (accurate to 0.001 N / mm²). 2 ) and wet CD or MD bending stiffness (accurate to N mm) 2 ).

[0160] Wet and dry CD super-sensitive 3-point bending method

[0161] The CD (lateral) bending characteristics of the test specimens were measured using an ultrasensitive 3-point bending test on a universal constant-speed extension test frame equipped with a load sensor suitable for measuring forces (the appropriate instrument being the MTS Alliance instrument using TestSuite software, purchased from MTS Systems Corp., Eden Prairie, MN, or equivalent). The test was performed on both dry and wet test specimens. The intent of this method is to simulate the deformation in the xy-plane produced by the wearer of the absorbent material during normal use. All tests were performed in a room controlled at 23°C ± 3°C and 50% ± 2% relative humidity.

[0162] The ultrasensitive three-point bending method aims to maximize the force signal-to-noise ratio when testing materials with very low bending forces. This is achieved by using a highly sensitive load cell (e.g., 5 N), a small span (the load is proportional to the cube of the span), and a wide specimen width (the total load measured is proportional to the width). The fixture is designed so that bending measurements are performed under tension, allowing for minimal fixture mass. 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 low as possible.

[0163] See Figures 12A to 12C The load sensor 1001 is mounted on the fixed clamp of the universal test frame. The ultra-sensitive clamp 1000 consists of three thin blades made of a lightweight, rigid material (such as aluminum or equivalent). Each blade has a thickness of 1.0 mm, rounded edges, 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), which are cut out to form a blade material with a height h of 5 mm along its horizontal edge. The two outer blades 1003a and 1003b are horizontally mounted to the movable clamp of the universal test frame, aligned parallel to each other with their horizontal edges vertically aligned. The span s between the two outer blades 1003a and 1003b is 5 mm ± 0.1 mm (inner edge to inner edge). The center blade 1002 is mounted on the fixed clamp of the universal test frame as a load sensor. When in place, the center blade 1002 is parallel to the two outer blades 1003a and 1003b, and centered on the midpoint between the outer blades 1003a and 1003b. The blade fixture includes integrated adapters adapted to be mounted in the appropriate positions on the universal test frame and locked in place such that the horizontal edge of the blade is orthogonal to the movement of the universal test frame crossbeam.

[0164] Prepare the test fluid for measuring wet test samples by adding 100.0 g of sodium chloride (reagent grade, any convenient source) to 900 g of deionized water in a 1 L Erlenmeyer flask. Stir until the sodium chloride is completely dissolved.

[0165] Prior to testing, samples were conditioned for two hours at 23℃±3℃ and 50%±2% relative humidity. Dry test specimens were taken from areas of the sample free of any seams, creases, or wrinkles. Dry specimens were prepared for CD bending (i.e., bending perpendicular to the transverse axis of the sample) by cutting the sample along CD (transverse; parallel to the transverse axis of the sample) to a width of 50.0 mm and along MD (longitudinal; parallel to the longitudinal axis of the sample) to a length of 100.0 mm, maintaining their orientation after cutting, and marking the surface facing the body (or the surface intended to face the finished product). Five duplicate dry test specimens were prepared in a similar manner.

[0166] The wet test specimens were initially prepared in the exact same manner as the dry test specimens, followed by the addition of the test fluid just before testing, as described below. The dry specimens were completely immersed in the test fluid for 60 seconds. After 60 seconds, the specimens were removed from the test fluid and held vertically for 30 seconds to allow any excess fluid to drip off. The test must be performed within 10 minutes of removing the wet test specimens from the test fluid. Five replicate wet test specimens were prepared in a similar manner.

[0167] The general-purpose test frame was programmed such that the movable chuck was set to move at a rate of 1.0 mm / s in the direction opposite to the fixed chuck. The chuck movement began with the specimen 1006 lying flat on the outer blades 1003a and 1003b without deflection, and continued as the inner horizontal edge of the cavity 1005 in the central blade 1002 contacted the top surface of the specimen 1006, further extending by an additional 4 mm of chuck movement. The chuck stopped at 4 mm and then immediately returned to zero at a rate of 1.0 mm / s. Force (N) and displacement (mm) were collected at 50 Hz throughout the process.

[0168] Before loading the test specimen 1006, the outer blades 1003a and 1003b move toward the central blade 1002, and then past the central blade, until a gap C of approximately 3 mm exists between the inner horizontal edges of the cavities 1004a and 1004b in the outer blades 1003a and 1003b and the inner horizontal edge of the cavity 1005 in the central blade 1002 (see [link to test specimen 1006]). Figure 12CThe specimen 1006 is placed within the gap C such that it spans the inner horizontal edges of cavities 1004a and 1004b in the outer blades 1003a and 1003b, oriented such that the MD (short side) of the specimen is perpendicular to the horizontal edges of the blades and the body-facing surface of the specimen is upward. The specimen 1006 is centered between the outer blades 1003a and 1003b. The outer blades 1003a and 1003b are slowly moved along a direction opposite to the fixed clamp until the inner horizontal edge of cavity 1005 in the central blade 1002 contacts the top surface of the specimen 1006. The test begins, and force and displacement data are continuously collected.

[0169] Force (N) versus displacement (mm) was plotted. The maximum peak force was recorded, accurate to 0.001 N. The area under the curve from the load start to the maximum peak force was calculated and recorded as bending energy, accurate to 0.001 N. mm. The recovery energy is calculated as the area under the curve of the force unloading from the maximum peak to 0.0 N, and recorded as the recovery energy, accurate to 0.001 N. mm. In a similar manner, the entire test sequence was repeated for a total of five dry test specimens and five wet test specimens.

[0170] For each test specimen type (dry and wet), calculate the arithmetic mean of the maximum peak forces among similar specimens, accurate to 0.001 N, and record them as dry peak load and wet peak load, respectively. For each test specimen type (dry and wet), calculate the arithmetic mean of the bending energy among similar specimens, accurate to 0.001 N. mm, and reported as dry bending energy and wet bending energy respectively. For each test specimen type (dry and wet), the arithmetic mean of the recovery energy among similar specimens was calculated, accurate to 0.001N. mm, and reported as dry recovery energy and wet recovery energy respectively.

[0171] Wet and dry coalescing compression methods

[0172] The compression-convexity test method uses a universal constant-speed extension test frame equipped with a load sensor (suitable instrument is the MTS Alliance, using TestSuite software, purchased from MTS Systems Corp., Eden Prairie, MN, or equivalent) to measure the force-displacement behavior of an intentionally “convex” absorbent article test sample during five cycles of load application (“compression”) and load removal (“recovery”), with the measured force within 1% to 99% of the limits of the load sensor. The test is performed on both dry and wet test specimens, the wet specimen being calibrated with a specified amount of test fluid. The method is intended to simulate the deformation in the z-plane of the crotch area of ​​the absorbent article or its components when worn by a wearer during sit-to-stand movements. All tests are conducted in a room controlled at 23°C ± 3°C and 50% ± 2% relative humidity.

[0173] Test equipment in Figures 13 to 14B The bottom fixing clamp 3000 consists of two matching sample clamps 3001, each 100 mm wide, mounted on its own movable platforms 3002a, 3002b. The clamps have 110 mm long "blades" 3009 that abut against a 1 mm thick hard rubber surface 3008. When closed, the clamps are flush with the inner side of their respective platforms. The clamps are aligned so that they hold unconvinced samples horizontally and orthogonally to the tension axis of the tension tester. The platforms are mounted on guide rails 3003, which allow them to move horizontally from left to right and lock into place. The guide rails have adapters 3004 compatible with the tension tester's bracket, enabling the platforms to be fixed horizontally and orthogonally to the tension axis of the tension tester. The upper clamp 2000 is a cylindrical plunger 2001 with an overall length of 70 mm and a diameter of 25.0 mm. The contact surface 2002 is flat and has no curvature. The plunger 2001 has an adapter 2003 that is compatible with the support of the load sensor, which can fix the plunger orthogonal to the tension axis of the tension tester.

[0174] Before testing, condition the test samples at 23℃±3℃ and 50%±2% relative humidity for at least 2 hours. Prepare the test specimens as follows. When testing a complete absorbent product, remove any release paper (if present) from any women's underwear adhesive on the garment-facing side of the product. Lightly apply talcum powder to the adhesive to reduce any stickiness. If hoops are present, cut them off with scissors so as not to interfere with the top sheet or any other underlying layers of the product. Place the product on the worktable with the body-facing surface facing up. Mark the intersection of the longitudinal and transverse center lines on the product. Use a rectangular die or equivalent cutting device to cut a specimen 100mm longitudinally by 80mm transversely, centered at the intersection of the center lines. When testing a layered or multilayered component of an absorbent product, place the layered or multilayered component on the worktable and oriented it to integrate into the finished product, i.e., identify the body-facing surface and the transverse and longitudinal axes. Use a rectangular die or equivalent cutting device to cut a specimen 100mm longitudinally by 80mm transversely, centered at the intersection of the center lines. Measure and record the mass of the sample, accurate to 0.001 grams. This is done by dividing the mass (g) by the area (0.008m²). 2 The basis weight of the sample is calculated and recorded as the basis weight, accurate to 1 g / m³. 2 .

[0175] The sample can be analyzed in both wet and dry conditions. Dry samples require no further preparation. Prepare the test fluid for metering the wet test sample by adding 100.0 g of sodium chloride (reagent grade, any convenient source) to 900 g of deionized water in a 1 L Erlenmeyer flask. Stir until the sodium chloride is completely dissolved. Meteringly add a total of 7 mL of the test solution to the wet sample, as detailed below.

[0176] Use a calibrated Eppendorf pipette to add the liquid dose, spreading the fluid over the entire body-facing surface of the specimen within a timeframe of approximately 3 seconds. Test the wet specimen 10.0 min ± 0.1 min after applying the dose.

[0177] Program the tension tester to zero the load sensor, then lower the upper clamp at 2.00 mm / s until the plunger contact surface contacts the sample and the reading at the load sensor is 0.02 N. Zero the clamp. Program the system to lower the clamp by 15.00 mm at 2.00 mm / s, then immediately raise the clamp by 15.00 mm at 2.00 mm / s. Repeat this cycle for a total of five cycles, without any delay between cycles. Collect data at a frequency of 50 Hz during all compression / decompression cycles.

[0178] Position the left platform 3002a 2.5 mm (distance 3005) from the side of the upper plunger. Lock the left platform in place. Platform 3002a will remain fixed throughout the experiment. Align the right platform 3002b 50.0 mm (distance 3006) from the fixing clamp. Raise the upper probe 2001 so that it does not obstruct the loading of the sample. Open both clamps 3001. See also Figure 14A Place the dry specimen in the fixture with its longitudinal edge (i.e., the 100mm long edge). With the dry specimen centered laterally, secure both edges firmly in the fixture. See [link to fixture]. Figure 14B Move the right platform 3002b 20mm toward the fixed platform 3002a to achieve a 30.0mm gap between the left and right clamps. When positioning the movable platform, allow the dry specimen to bend upwards. Now manually lower the probe 2001 until the bottom surface is approximately 1cm above the top of the bent specimen.

[0179] Begin testing and continuously collect force (N) versus displacement (mm) data for all five cycles. Plot the force (N) versus displacement (mm) curves individually for each cycle. Representative curves are shown below. Figure 15A From this curve, determine the maximum dry compressive force for each cycle, accurate to 0.01 N, then multiply by 101.97 and record, accurate to 1 gram-force. (TD-E2) / (TD-E1) Calculate the "% dry recovery" between the "first cycle" and the "second cycle" and record it to an accuracy of 0.01%, where TD is the total displacement and E2 is the elongation on the second compression curve, which exceeds 0.02 N. Similarly, calculate it as (TD-E1) / (TD-E1). Calculate the % dry recovery between the first and other cycles and record it, accurate to 0.01%. See also Figure 15B The dry compression energy of cycle 1 is calculated based on the area under the compression curve (i.e., area A+B), and recorded to an accuracy of 0.1 N. mm. The dry energy loss from cycle 1 is calculated based on the area between the compression and decompression curves (i.e., area A) and recorded to an accuracy of 0.1 N. mm. Calculate the dry recovery energy of cycle 1 based on the area under the decompression curve (i.e., area B) and report it to an accuracy of 0.1 N. mm. Similarly, calculate the dry compression energy (N) for each of the other cycles. mm), dry energy loss (N) mm) and dry recovery energy (N) (mm), and record the data, accurate to 0.1 N. mm. In a similar manner, a total of five replicate dry test specimens were analyzed for each parameter as described above, including basis weight, and the arithmetic mean between the five dry replicates was reported.

[0180] The entire procedure is now repeated for a total of five wet test specimens. The results of each of the five cycles are reported as the arithmetic mean of the following values ​​among the five wet repetitions: maximum wet compressive force for each cycle (accurate to 1 gF), wet compressive energy for each cycle (accurate to 0.1 N). mm), wet energy loss per cycle (accurate to 0.1N). mm), wet recovery energy per cycle (accurate to 0.1N). mm) and the wet recovery % for each cycle. Of particular importance are the fifth-cycle wet recovery energy and the fifth-cycle wet recovery % characteristics from this test method.

[0181] CD cyclic elongation to 3% strain method

[0182] The cyclic tensile and recovery response of absorbent article specimens was measured using a universal constant-rate elongation test frame for ten cycles of sustained load application (“elongation”) and load removal (“recovery”). The test specimen was cycled ten times to 3% of the engineering strain and then returned to zero engineering strain. For each cycle, the 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”) were calculated and reported. The intent of this method is to understand the ability of a specimen to be stretched in the xy-plane due to body forces and then recover to its original state. All measurements were performed in a laboratory maintained at 23°C ± 2°C and 50% ± 2% relative humidity, with the test specimens conditioned in this environment for at least 2 hours prior to testing.

[0183] A suitable universal constant-speed extension test frame is an MTS Alliance or equivalent that interfaces with a computer running TestSuite control software (purchased from MTS SystemsCorp, Eden Prairie, MN). The universal test frame is equipped with a load sensor, and the force being measured is within 1% to 99% of the sensor's limits. The clamps used to hold the test specimen are lightweight (<80 grams) vise-like clamps with a blade or serrated edge clamping surface at least 40 mm wide. The clamps are mounted on the universal test frame and are installed such that they are horizontally and vertically aligned with each other.

[0184] Test specimens are taken from rolls or sheets of raw material or from a layer of material removed from an absorbent article. When cutting the material layer from the absorbent article, care is taken not to contaminate or deform the layer during the process. The removed layer should be free of residual adhesive and any fibers that may have transferred from the underlying layer. To ensure the removal of all adhesive and any transferred fibers, the layer is immersed in a suitable solvent that will dissolve the adhesive and release any transferred fibers present without adversely affecting the material itself. One such solvent is THF (tetrahydrofuran, CAS 109-99-9, for general purposes, available from any readily available source). After solvent immersion, the material layer is allowed to air dry thoroughly in a manner that prevents excessive stretching or other deformation of the material. After the material has dried, the test specimen is obtained. The test specimen is cut from any area of ​​the test material free of creases or wrinkles. The test specimen is 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 specimens from absorbent articles of different sizes and widths, the total specimen length (L) 总计 The results may vary from product to product, therefore the results will be 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 expected longitudinal axis). Specimen width (w) = 25.4 mm. Measure and record the total specimen length (L). 总计 (Accurate to 0.1 mm). Prepare five repeat test specimens in a similar manner.

[0185] The thickness (t) of the test specimen is measured using a manually operated micrometer equipped with a pressure foot capable of applying a stable pressure of 0.1 psi ± 0.01 psi. This manually operated micrometer is a heavy-duty instrument with readings accurate to 0.01 mm. A suitable instrument is the Mitutoyo Series 543 ID-C Digimatic, or equivalent, purchased from VWR International. The pressure foot is a flat, circular, movable surface with a diameter not exceeding 25.4 mm. The test specimen is supported by a horizontal, flat reference platform, which is larger than and parallel to the surface of the pressure foot. The micrometer is zeroed against the horizontal, flat reference platform. The test specimen is placed on the platform, centered below the pressure foot. The pressure foot is lowered manually at a rate of 3 ± 1 mm / s until the full weight of the pressure is applied to the specimen. After 5 seconds, the thickness is recorded as the specimen thickness (t), accurate to 0.01 mm.

[0186] Prepare a general test frame as follows. Set the initial clamp-to-clamp spacing to a nominal gauge length (L) shorter than the total specimen length. 标称 ), and allows the sample to be securely clamped at both ends (i.e., L 标称 <L 总计Then the clamps are zeroed. The test frame is programmed to move the clamps closer together with an intentional 1mm relaxation to ensure there is no pre-tension on the test specimen at the start of the test. (During this movement, the specimen will become relaxed between the tension clamps.) Next, the clamps will be moved away at a relaxation rate of 1mm / s until a relaxation preload of more than 0.05N is achieved. At this point, the following holds true: 1) The clamp position signal (mm) is defined as the specimen relaxation (L). 松弛 2) The initial gauge length (L0) is calculated as the nominal gauge length plus the relaxation L0 = L 标称 +L 松弛 The units are in millimeters. 3) The chuck extension (ΔL) is set to zero (0.0 mm). 4) The chuck displacement (mm) is set to zero (0.0 mm). At this position, the engineering strain is zero, 0.0. The engineering strain is calculated as the length change (ΔL) divided by the initial length (L0). Engineering strain = ΔL / L0. For one test cycle, the clamps are moved away at an initial speed of 1 mm / s until the engineering strain endpoint exceeds 0.03 mm / mm, and then the clamps are moved towards each other at an initial speed of 1 mm / s until the chuck return position when the chuck signal becomes less than 0 mm. This test cycle is repeated until a total of 10 cycles are completed.

[0187] The test specimen is inserted into the clamp so that its long axis is parallel to and centered with the movement of the clamp. The test begins and time, force, and displacement data are continuously collected at a data acquisition rate of 100 Hz.

[0188] Plot the load (N) versus displacement (mm) for all ten cycles. For each cycle, perform the following: Record the peak load to an accuracy of 0.01 N. Calculate the peak energy (E). 峰值 The area under the load-displacement curve from the start of the cycle to the strain endpoint of 0.03 mm / mm (during the loading portion of the cycle) is recorded, accurate to 0.01 N. mm. Calculate the return energy (E) 返回 The area under the load-displacement curve from the strain endpoint of 0.03 mm / mm to the chuck return at 0 mm (during the unloading portion of the cycle) is recorded as the recovery energy, accurate to 0.01 N. mm. Normalized peak energy (NE) 峰值 The calculation is the peak energy divided by the initial length, where NE 峰值 =E 峰值 / L0, and record it, accurate to 0.01mN. Return the normalized energy (NE). 返回 The calculation is the return energy divided by the initial length (NE). 返回 =E 返回 / L0), and record it, accurate to 0.01mN. NE 峰值 and NE 返回 The unit is millinewtons (mN).

[0189] Now plot the stress (σ) versus strain curves for all ten cycles, and perform the following operations for each cycle. (In N / mm) 2 The engineering stress in units is the load divided by the cross-sectional area of ​​the specimen, where the cross-sectional area is the specimen width (w) multiplied by the thickness (t), σ = load / (w) For the line between the point of minimum force and the point of maximum force (during the loading portion of the cycle), determine the modulus or the slope of the stress-strain curve and record it as the modulus, accurate to 0.01 N / mm. Calculate the stiffness by multiplying the modulus by the specimen thickness and record it as tensile stiffness, accurate to 0.01 N / mm. The strain of the test specimen at the start of the cycle is defined as the strain when the cycle exceeds a relaxation preload of 0.05 N (during the loading portion of the cycle) and recorded as the initial strain of the cycle, accurate to 0.01 mm / mm. The strain of the test specimen at the end of the cycle is defined as the strain when the load becomes less than the 0.05 N preload of the cycle (during the unloading portion of the cycle) and recorded as the permanent strain, accurate to 0.01 mm / mm. In a similar manner, now repeat the entire procedure for all five repetitions.

[0190] For each of the ten cycles, the arithmetic mean of the values ​​of the five repeated test specimens is calculated for each parameter and reported as peak load (accurate to 0.01 N), normalized peak energy (accurate to 0.01 mN), normalized recovery energy (accurate to 0.01 mN), tensile stiffness (accurate to 0.01 N / mm), initial strain of the cycle (accurate to 0.01 mm / mm), and permanent strain (accurate to 0.01 mm / mm).

[0191] Methods for measuring pattern spacing and area at structural bonding sites

[0192] On images of absorbent article samples acquired using a flatbed scanner, the spacing between discrete structural bonding sites used to create the quilted pattern on the absorbent article sample, and the total area occupied by the sum of these elements in a specified region of the sample, were measured. The scanner was capable of scanning in reflective mode at a resolution of 2400 dpi and 8-bit grayscale. A suitable scanner was the Epson Perfection V750 Pro, or equivalent, from Epson America Inc., Long Beach, CA. The scanner interacted with a computer running an image analysis program. A suitable program was ImageJ v. 1.52, National Institute of Health, USA, or equivalent. The sample images were distance-calibrated against a ruler image acquired by NIST. To achieve maximum contrast, the samples were backed against an opaque, uniformly colored black background before image acquisition. All tests were performed in a conditioning chamber maintained at approximately 23°C ± 2°C and approximately 50% ± 2% relative humidity.

[0193] Prepare each test sample as follows. Remove the absorbent material from any existing packaging paper. If the material is folded, gently unfold it and smooth out any wrinkles. If wings are present, extend them, but keep the release paper intact. Condition the test samples for 2 hours at a temperature of approximately 23°C ± 2°C and a relative humidity of approximately 50% ± 2%.

[0194] Obtain the image as follows. Place the ruler on the scanning bed with its orientation parallel to the side of the scanner glass. Acquire an image of the ruler (calibration image) in reflective mode at a resolution of 2400 dpi (approximately 94 pixels / mm) and 8-bit grayscale. Save the calibration image as an uncompressed TIFF file. After obtaining the calibration image, remove the ruler from the scanner glass and scan the test sample under the same scanning conditions as follows. Place the test sample in the center of the scanner glass and hold it in place, if necessary, so that it lies flat with the body-facing surface of the sample facing the scanner glass surface. Orient the sample so that the entire sample is within the glass surface. Place a black background on top of the sample, close the scanner lid, and acquire a scan image of the entire sample with the same settings as for the calibration image. Save the sample image as an uncompressed TIFF file.

[0195] The following analysis is performed on the sample image. Open the calibration image file in the image analysis program and use the imaging ruler to calibrate the image resolution to determine the number of pixels per millimeter. Now open the sample image in the image analysis program and set the distance scale using the image resolution determined from the calibration image. Now visually inspect the pattern of embossed elements present on the sample in the image and identify the pattern area to be analyzed. For example, an absorbent article can be divided into three equal-length areas in the longitudinal direction, such as the front third area (area 1), the middle third area (area 2), and the rear third area (area 3). Use the image analysis tool to draw a shape along the outer perimeter of the first discrete area to be analyzed. Measure the area of ​​this first area and record it as the total area of ​​area 1, accurate to 0.01 mm. 2 Now, measure the area of ​​each individual, discrete embossing element located inside the perimeter of zone 1 as follows. Draw a minimum boundary circle around each individual embossing element such that no part of the embossing element lies outside the boundary circle. Now measure the area of ​​the boundary circle of the embossing element and record the area of ​​the embossing element, accurate to 0.01 mm. 2 Similarly, the area of ​​each embossed element, including the portion of the embossed element located within zone 1, is measured and recorded to an accuracy of 0.01 mm. 2 Now, sum the areas of all embossed elements in zone 1 and record the total embossed element area of ​​zone 1, accurate to 0.01 mm. 2 The total area of ​​embossed elements in zone 1 is divided by the total area of ​​zone 1, then multiplied by 100, and recorded as the percentage of the total area of ​​zone 1 occupied by the embossed elements. The spacing between each discrete embossed element in zone 1 is measured as follows. As described herein, the distance from the center of the smallest boundary circle drawn around the discrete embossed element in zone 1 to the center of the smallest boundary circle drawn around the nearest neighbor discrete embossed element in zone 1 is measured and recorded as the embossed spacing, accurate to 0.01 mm. In a similar manner, this is repeated for all adjacent embossed elements in zone 1, and each distance is recorded to an accuracy of 0.01 mm. The arithmetic mean of all measured embossed spacings between the nearest neighbors in zone 1 is now calculated and recorded as the embossed spacing of zone 1, accurate to 0.01 mm.

[0196] In a similar manner, the entire procedure was repeated for each additional zone containing embossed elements present on the test sample, and marked accordingly as zone 2, zone 3, etc.

[0197] Nonwoven thickness-pressure method

[0198] The thickness of the test specimen is measured as the distance between the reference platform on which the specimen rests and the pressure foot on which a specified amount of pressure is applied to the specimen over a specified time. For the purposes of this paper, two different confining pressures (7 g / cm²) are used. 2 and 70g / cm 2Thickness was measured and reported. All measurements were performed in a laboratory maintained at 23°C ± 2°C and 50% ± 2% relative humidity, and the test specimens were conditioned in this environment for at least 2 hours prior to testing.

[0199] The thickness was measured using a manually operated micrometer equipped with a stable pressure (7 g / cm³). 2 and 70g / cm 2 The pressure foot is applied to the test specimen. The manually operated micrometer is a heavy-duty instrument with readings accurate to 0.01 mm. A suitable instrument is the Mitutoyo Series 543 ID-C Digimatic, or equivalent, from VWR International. The pressure foot is a flat, circular, movable surface with a diameter smaller than the test specimen, capable of applying the required pressure. A suitable pressure foot has a diameter of 25.4 mm; however, smaller or larger pressure feet can be used depending on the size of the specimen being measured. The test specimen is supported by a horizontal, flat reference platform that is larger than and parallel to the surface of the pressure foot. The system is calibrated and operated according to the manufacturer's instructions.

[0200] Test specimens taken from raw material rolls or sheets, or from material layers removed from absorbent articles, are measured. When removing material layers from absorbent articles, care is taken to avoid contaminating or deforming the layer during the process. The removed layer should be free of residual adhesive and any fibers that may have transferred from the underlying layer. To ensure the removal of all adhesive and any transferred fibers, the layer is immersed in a suitable solvent that will dissolve the adhesive and release any transferred fibers present without adversely affecting the material itself. One such solvent is THF (tetrahydrofuran, CAS 109-99-9, for general purposes, available from any readily available source). After solvent immersion, the material layer is allowed to air dry thoroughly to prevent excessive stretching or other deformation of the material. Once the material is dry, a test specimen is obtained from an area free of creases or wrinkles, and it must be larger than the pressure foot.

[0201] In order to achieve 7g / cm 2 To measure the thickness under confining pressure, first zero the micrometer relative to a horizontal, flat reference platform. Place the test specimen on the platform, with the test position centered below the pressure foot. Gently lower the pressure foot at a rate of 3.0 mm ± 1.0 mm per second until full pressure is applied to the test specimen. Wait 5 seconds, then record the thickness of the test specimen to an accuracy of 0.01 mm. Repeat this process for a total of ten test specimens. Calculate the thickness at 7 g / cm³. 2 The arithmetic mean of all thickness measurements obtained under the confining pressure is reported as 7 g / cm³. 2 The thickness is accurate to 0.01mm.

[0202] In order to achieve 70g / cm 2 To measure the thickness under confining pressure, first zero the micrometer relative to a horizontal, flat reference platform. Place the test specimen on the platform, with the test position centered below the pressure foot. Gently lower the pressure foot at a rate of 3.0 mm ± 1.0 mm per second until full pressure is applied to the test specimen. Wait 5 seconds, then record the thickness of the test specimen to an accuracy of 0.01 mm. Repeat this process for a total of ten test specimens. Calculate the thickness at 70 g / cm³. 2 The arithmetic mean of all thickness measurements obtained under the confining pressure is reported as 70 g / cm³. 2 The thickness is accurate to 0.01mm.

[0203] Touch and rewet method

[0204] The touch-rewetting method is a quantitative method for measuring the mass of a liquid that flows from an absorbent article test sample while a specified weight has been applied for a specified duration. The sample has been metered with a specified volume of artificial volatile oil (AMF; as described herein). All tests were performed in a laboratory maintained at 23°C ± 2°C and 50% ± 2% relative humidity.

[0205] Use a syringe pump equipped with a disposable syringe to meter the addition of the test sample. A suitable pump is a Perfusor. ® Compact S (purchased from B. Braun) or equivalent, and must be able to accurately dispense AMF at a rate of 42 ml / min. A disposable syringe with sufficient volume (e.g., BD Plastipak 20 mL) is connected to a flexible tube with a 3 / 16" inner diameter (e.g., Original Perfusor). ® The tubing (purchased from Brau, or equivalent) was prepared as described herein and brought to room temperature (23°C ± 2°C) before use in this test. Before starting the measurement, the syringe was filled with AMF and the flexible tubing was filled with the liquid, and the dispensing rate (42 ml / min) and volumetric volume (4.0 mL ± 0.05 mL) were verified according to the manufacturer's instructions. The flexible tubing was then mounted vertically above the test sample, with the tip of the tubing 19 mm above the surface of the test sample. Note that the AMF must be removed from the syringe and thoroughly mixed every 15 minutes.

[0206] The rewetting weight assembly consists of an acrylic plate and stainless steel weights. The acrylic plate measures 65mm x 80mm and is approximately 5mm thick. Together with the acrylic plate, the stainless steel weights provide a combined mass of 2 pounds (907.19g) to apply a pressure of 0.25 psi below the surface of the acrylic plate.

[0207] For each test sample, five 4-inch x 4-inch filter papers were used as the rewetting substrate. Prior to testing, the filter papers were conditioned at 23°C ± 2°C and 50% ± 2% relative humidity for at least 2 hours. Suitable filter papers had a basis weight of approximately 139 gsm, a thickness of approximately 700 micrometers, an absorption rate of approximately 1.7 seconds, and were available from Ahlstrom-Munksjo North America LLC, Alpharetta, GA VWR International as Ahlstrom Grade 989 or equivalent.

[0208] Prepare the test samples according to the following steps. Before testing, condition the test samples at 23℃±2℃ and 50%±2% relative humidity for at least 2 hours. Remove the test samples from all packaging, being careful not to press or pull the products during handling. Place the test samples on a horizontal, rigid, flat surface and gently smooth out any creases. Determine the test location as follows: For symmetrical samples (i.e., when divided laterally along the midpoint of the sample's longitudinal axis, the front of the sample has the same shape and size as the rear), the test location is the intersection of the midpoint of the sample's longitudinal axis and the midpoint of the transverse axis. For asymmetrical samples (i.e., when divided laterally along the midpoint of the sample's longitudinal axis, the front of the sample does not have the same shape and size as the rear), the test location is the intersection of the midpoint of the sample's longitudinal axis and the transverse axis located at the midpoint of the sample's wing. Prepare a total of three test samples.

[0209] Place the test sample on a level, flat, rigid surface, with the previously identified test position centered directly below the tip of the flexible tube. Adjust the height of the tube so that it is 19.0 mm above the test sample surface. Start the pump to dispense 4.0 mL ± 0.05 mL of AMF at a rate of 42 ml / min. Once the AMF has been fully dispensed, start a 10-minute timer. Now obtain the mass of five filter papers and record it as a dry mass accurate to 0.001 g. After 10 minutes, place the five pre-weighed filter papers on the test sample, centering the stack in the metering position. Now place the acrylic plate at the center of the top of the filter papers, with the long side of the plate parallel to the longitudinal axis of the test sample. Now carefully lower the stainless steel weight centered above the acrylic plate and immediately start a 30-second timer. After 30 seconds, gently remove the rewetting weight and acrylic plate and set aside. Obtain the mass of five filter papers and record it as a wet mass accurate to 0.001 g. Subtract the dry weight from the wet weight of the filter paper and record the result as rewetting, accurate to 0.001 g. Wipe away any residual test liquid from the bottom of the acrylic plate before testing the next sample. Repeat the test for a total of three replicate samples in a similar manner.

[0210] Calculate the arithmetic mean of rewetting in the three repeated test samples and report it as “touch rewetting”, accurate to 0.001 g.

[0211] Preparation of Artificial Menstrual Fluid (AMF)

[0212] Artificial blood serum (AMF) is a mixture of defibrinated sheep blood, phosphate-buffered saline solution, and a mucilage component. AMF is prepared to have a viscosity between 7.15 centistokes and 8.65 centistokes at 23°C.

[0213] Measure the viscosity of AMF using a low-viscosity rotational viscometer (a suitable instrument is the Cannon LV-2020 rotational viscometer with a UL adapter from Cannon Instrument Co., State College, PA, or an equivalent instrument). Select an appropriate spindle size within the viscosity range and operate and calibrate the instrument according to the manufacturer's instructions. Measurements should be performed at 23°C ± 1°C and 60 rpm. Report results to an accuracy of 0.01 centistokes.

[0214] The reagents required for AMF preparation include: defibrinated sheep blood with a cell hematocrit of 38% or greater (collected under sterile conditions, purchased from Cleveland Scientific, Inc., Bath, OH, or equivalent); gastric mucin with a viscosity of 3-4 centistokes when prepared as a 2% aqueous solution (crude form, sterile, purchased from American Laboratories, Inc., Omaha, NE, or equivalent); 10% v / v lactic acid aqueous solution; 10% w / v potassium hydroxide aqueous solution; disodium hydrogen phosphate (reagent grade); sodium chloride (reagent grade); sodium dihydrogen phosphate (reagent grade); and distilled water, each purchased from VWR International or equivalent sources.

[0215] The phosphate buffered saline solution consists of two separately prepared solutions (solution A and solution B). To prepare 1 L of solution A, add 1.38 g ± 0.005 g sodium dihydrogen phosphate and 8.50 g ± 0.005 g sodium chloride to a 1000 mL volumetric flask, and add distilled water. Mix thoroughly. To prepare 1 L of solution B, add 1.42 g ± 0.005 g disodium hydrogen phosphate and 8.50 g ± 0.005 g sodium chloride to a 1000 mL volumetric flask, and add distilled water. Mix thoroughly. To prepare the phosphate buffered saline solution, add 450 mL ± 10 mL of solution B to a 1000 mL beaker and stir at low speed on a stirring plate. Insert a calibrated pH probe (accurate to 0.1) into the beaker containing solution B, and while stirring, add enough solution A to bring the pH to 7.2 ± 0.1.

[0216] The mucus component was a mixture of phosphate-buffered saline solution, potassium hydroxide solution, gastric mucin, and lactic acid solution. The amount of gastric mucin added to the mucus component directly affected the final viscosity of the prepared AMF. To determine the amount of gastric mucin required to obtain AMF within the target viscosity range (7.15 cP–8.65 cP at 23°C), three batches of AMF with different amounts of gastric mucin were prepared in the mucus component. The required precise amount was then extrapolated from the concentration-viscosity curve using a three-point least-squares linear fit. The successful range for gastric mucin was typically between 38 g and 50 g.

[0217] To prepare approximately 500 mL of the mucus component, 460 mL ± 10 mL of the previously prepared phosphate-buffered saline solution and 7.5 mL ± 0.5 mL of a 10% w / v potassium hydroxide aqueous solution were added to a 1000 mL heavy-duty glass beaker. The beaker was placed on a hot plate with stirring, and the temperature was raised to 45 °C ± 5 °C while stirring. A predetermined amount of gastric mucin (± 0.50 g) was weighed and slowly sprinkled into the previously prepared liquid, which had reached 45 °C, without agglomeration. The beaker was covered and mixing continued. The temperature of the mixture was raised to above 50 °C but not exceeding 80 °C over 15 minutes. Heating was continued for 2.5 hours while maintaining this temperature range and with gentle stirring. After 2.5 hours, the beaker was removed from the hot plate and cooled to below 40 °C. Then, 1.8 mL ± 0.2 mL of a 10% v / v lactic acid aqueous solution was added and thoroughly mixed. The mucus component mixture was autoclaved at 121 °C for 15 minutes and cooled for 5 minutes. Remove the mixture of viscous components from the autoclave and stir until the temperature reaches 23℃±1℃.

[0218] The temperature of the sheep blood and mucus components should be maintained at 23°C ± 1°C. Using a 500mL graduated cylinder, measure the volume of the entire batch of previously prepared mucus components and add it to a 1200mL beaker. Add an equal volume of sheep blood to the beaker and mix thoroughly. Using the viscosity method described above, ensure that the viscosity of the AMF is between 7.15 cP and 8.65 cP. If not, dispose of the batch and prepare another batch as needed to adjust the mucus components.

[0219] Unless intended for immediate use, qualified AMF should be refrigerated at 4°C. After preparation, AMF can be stored in an airtight container at 4°C for up to 48 hours. AMF must be brought to 23°C ± 1°C before testing. Discard any unused portions after testing.

[0220] Example / Data

[0221] The following data and examples (including comparative examples) are provided to help illustrate the upper and lower nonwoven layers and / or absorbent articles described herein. The illustrative structures are given for purposes of illustration only and should not be construed as limiting the scope of this disclosure, as many variations are possible without departing from the spirit and scope of the invention.

[0222] Nonwoven material testing

[0223] A series of measurements were performed on the nonwoven material to evaluate its ability to be used as an upper and / or lower nonwoven layer in the absorbent core structure described herein. Samples A through G are embodiments according to this disclosure. Comparative sample H is a comparative embodiment. Samples A through G and comparative sample H are described in Table 1 below.

[0224] Samples A to G and comparative sample H were evaluated using the CD cyclic elongation to 3% strain method, fracture strain method, wet and dry CD ultrasensitive three-point bending method, and nonwoven thickness-pressure method. The results are shown in Table 2.

[0225] Table 1: Description of Nonwoven Materials

[0226]

[0227] 1 Purchased ATB Z87G-40 from Xiamen Yanjan New Material Co. (China)

[0228] 2 With Sawasoft ® 53FC041001 was purchased from Sandler GmbH (Germany).

[0229] 3 With Sawasoft ® 553FC041005 (Option 82) was purchased from Sandler GmbH (Germany).

[0230] 4 Purchased Aura 20 from Xiamen Yanjan New Material Co. (China)

[0231] 5 Purchased from Jacob Holms Industries (Germany) under license number S25000541R01.

[0232] 6 Purchased from PFN nonwovens Czech SRO (Czech Republic) using PFNZN 18G BICO8020 PHI 6.

[0233] 7 The PEGZN25 BICO7030 Phobic was purchased from PFN nonwovens Czech SRO (Czech Republic).

[0234] 8 Purchased from DunnPaper (USA) for 3028.

[0235] Table 2 :

[0236]

[0237] It is believed that nonwoven materials suitable for the upper and / or lower nonwoven layers can be strained (elongated) by balanced stretching and substantially return to their initial state, thereby helping the absorbent core structure and / or absorbent article to recover from deformation during body movement. Particularly suitable nonwoven materials for the upper nonwoven layer can provide fluid handling properties that effectively deliver fluids deep into the inner core layer, thus helping to provide a close and comfortable fit to the body when feeling dry. To achieve this, suitable nonwoven materials for the upper nonwoven layer exhibit a relatively low density (e.g., at 7 g / cm³). 2 The pressure is 0.03 g / cm³. 3 Up to 0.07 g / cm 3 This allows fluid to be effectively drained from the upper nonwoven layer into the underlying core layer. Furthermore, a suitable nonwoven material for the upper nonwoven layer is required even under high body compressive forces (i.e., 70 g / cm³). 2 Even under pressure, it can maintain a relatively fluffy thickness, so that the fluid residing in the inner core layer will not be discharged from the absorbent core structure, thus avoiding a wet feeling on the body.

[0238] Samples A through C and E were found to be suitable materials for the upper and / or lower nonwoven layers. Specifically, samples A through C and E exhibited a permanent strain of 0.013 mm / mm or less, indicating that the material can elongate and recover, and has a fracture strain greater than 10% before tearing. Samples A through C and E also required relatively low bending energy (less than 1.6 N). (proven by dry bending energy of mm), while with a value greater than 0.03N. The dry recovery energy from bending was mm. Samples A to C and E showed a recovery energy of 7 g / cm. 2 0.03 g / cm under pressure 3 Up to 0.07 g / cm 3 The relatively low density and at 7 g / cm³ 2 The thickness of these materials, ranging from 0.80 mm to 1.21 mm under pressure, demonstrates that they are porous and have a more open fiber network structure, which can contribute to effective fluid handling performance.

[0239] Sample D was found to have a permanent strain of 0.016 mm / mm, demonstrating that the material may significantly elongate during manufacturing and / or use without returning to its initial state. Simultaneously, Sample D was found to be highly compressible under body pressure, such as 70 g / cm³. 2 The thickness of 0.19 mm demonstrates that the material will become denser under body compression and may not adequately expel fluid through the inner core. Samples F and G exhibit less than 0.03 N. The dry recovery energy of mm indicates that the material may not be able to recover from deformation, making it unsuitable for use as an upper nonwoven layer. However, when combined with the upper nonwoven layer described herein, samples D, F, and G may be suitable materials for the lower nonwoven layer.

[0240] Comparing sample H, it exhibits a fracture strain of less than 5% and at 70 g / cm². 2 The thickness is less than 0.2 mm. Furthermore, comparative sample H was found to tear upon wetting. Therefore, comparative sample H is insufficient for use as either an upper or lower nonwoven layer.

[0241] For the reader's convenience, Table 3 is provided. Table 3 includes an incomplete list of properties and an incomplete list of corresponding values ​​for each property that the particularly suitable upper nonwoven layer of this disclosure may exhibit.

[0242] Table 3: Upper Nonwoven Layer

[0243]

[0244] Finished product testing

[0245] Absorbent articles were tested to evaluate the impact of short cellulose fibers on core integrity (i.e., core cracking and / or tearing). Samples 1 through 3 represent absorbent articles comprising a top sheet, a bottom sheet, and an absorbent core structure positioned between them as described herein. The absorbent core structures of Samples 1 through 3 contain varying amounts of short cellulose fibers. Samples 4 through 6 represent comparative absorbent articles comprising a top sheet, a bottom sheet, and an absorbent core disposed between them. The absorbent cores of Samples 4 through 6 represent conventional high-basic heavy cellulose cores and contain varying amounts of short cellulose fibers.

[0246] Sample 1 :

[0247] Prepare disposable absorbent products in the form of feminine hygiene pads having the following components:

[0248] Top sheet – The top sheet is a 22.4 gsm polyethylene molded film, which was purchased from Xiamen Yanjan New Material Co. (India) under the serial number DS02-172.

[0249] Upper Nonwoven Layer – The upper nonwoven layer is a 40gsm carded elastic nonwoven fabric containing 60% 2 dtex / 40% 4 dtex blend BiCo (PE / PET), purchased from Xiamen Yanjan NewMaterial Co. (China) as ATB Z87G-40.

[0250] Inner core layer – The inner core layer is a homogeneous mixture of 150 g sm cellulose pulp and 60 g sm superabsorbent granules (purchased from Nippon Shokubai (Japan) using Aqualic CA L-805). The cellulose pulp is 100% SuperSoft purchased from International Paper Company (Memphis, Tn). ® Untreated fluff pulp.

[0251] The lower nonwoven layer is a 18gsm spunbond nonwoven fabric containing 100% 2.0% polypropylene, which was purchased from PFN nonwovens Czech SRO (Czech Republic) as PFNZN 18G 100%PP PHI 6.

[0252] Film – The film is an 18gsm polypropylene film, which was purchased from Swanson Plastics India (India).

[0253] First, a top sheet is coated with 5gsm adhesive (D3151 NG, HB Fuller). Then, an upper nonwoven layer is deposited onto the top sheet. Simultaneously, the inner core layer is produced in an air-laid process. A flow of cellulose pulp and AGM is carried on a rapidly moving airflow and deposited into three-dimensional pockets on a rotational molding drum with a vacuum below to draw the cellulose and AGM into the pockets in a resting station. The homogenized cellulose and AGM clumps are held under vacuum on the molding drum until they are deposited directly onto the upper nonwoven layer pre-coated with 5gsm adhesive (D3151 NG, HB Fuller), and then sealed with a second remaining nonwoven layer pre-coated with 5gsm adhesive (D3151 NG, HB Fuller) to create the absorbent core. The widths of the upper and lower nonwoven webs are wider than the maximum widths of the shaped cellulose and AGM inner core layers to achieve effective peripheral sealing at the junction of the two nonwoven layers, at least on the leftmost and rightmost sides of the absorbent core structure. A heated embossing unit is used on the manufacturing line to apply pressure to the flexural bonding channel areas. Figure 11B The pattern shown is then applied. The film is then bonded to the outward-facing surface of the lower nonwoven layer using 5gsm adhesive (D3151 NG, HB Fuller).

[0254] Sample 2 :

[0255] Feminine sanitary pads were prepared as in Sample 1, except that the cellulose pulp contained 16% Eucalyptus. ®(Purchased from Suzano, Brazil) and 84% of SuperSoft ® Untreated fluff pulp, both are calculated by weight of cellulose pulp.

[0256] Sample 3 :

[0257] Feminine sanitary pads were prepared as in Sample 1, except that the cellulose pulp contained 32% Eucalyptus. ® (Purchased from Suzano) and 68% of SuperSoft ® Untreated fluff pulp, both are calculated by weight of cellulose pulp.

[0258] Comparison Samples 4 to 7 :

[0259] Prepare disposable absorbent products in the form of feminine hygiene pads having the following components:

[0260] Top sheet – The top sheet is a 22.4 gsm polyethylene molded film, which was purchased from Yanjan (Egypt) under the name MM1-172.

[0261] Core Layer – The core layer is 430gsm cellulose pulp. This cellulose pulp is 100% SuperSoft, purchased from International Paper Company (Memphis, Tn). ® Untreated fluff pulp.

[0262] Film – The film is a 12gsm blown film (3 layers) of a metallocene-LLDPE, LDPE and HDPE composition based on polyolefin resins, which was purchased from RKW Group (Germany) as Theo 12gsm 168mm film.

[0263] First, a stream of cellulose fibers is carried on a rapidly moving airflow and deposited into a three-dimensionally shaped pocket on a rotational molding drum, which has a vacuum underneath to draw the cellulose into the pocket in a resting station. This pocket shape provides the actual physical shape for direct deposition onto a topsheet pre-coated with 4.1 gsm adhesive (D3151 NG, HB Fuller). Deep embossed channels are then applied as described in U.S. Patent No. 11,696,858. These channels are formed by heating, compressing, and embossing the materials of the topsheet and absorbent core toward the backsheet, such that the channel portion of the absorbent article has a higher density than the rest of the liner, which is intended to provide structural wet integrity of the product in use. The product is then sealed with a backsheet pre-coated with 9 gsm adhesive (D3151 NG, HB Fuller).

[0264] Absorbent core integrity is determined by core cracking grading of the pad after it has been worn during menstruation and collected for testing. The core cracking grade is determined by visual inspection of the pad using a lightbox. Recycled pads are graded according to the following scale:

[0265] 1. Good – Consumers may not see the gap (crack or tear), the crack length is 0mm-30mm, the crack width is less than 1mm, and the number of crack locations is less than 3.

[0266] 2. Medium – Consumers may be able to see gaps, with crack length greater than 30mm but less than 60mm, crack width greater than 1mm but less than 2mm, and the number of crack locations is 4-6.

[0267] 3. Severe – Consumers are very likely to detect core breakage, and can see missing or very wide cores, cracks wider than 2mm, and more than 6 crack locations.

[0268] The results are shown in Table 4 below.

[0269] Table 4: Core Integrity

[0270]

[0271] Compared to thicker, high-basicity (i.e., greater than 350 gsm) cellulose pulp-based cores, low-basicity (i.e., 350 gsm or less), low-density cellulose pulp-based absorbent cores have traditionally been considered structurally less stable and have a higher risk of tearing and / or coalescence during use. The inclusion of short cellulose fibers (such as eucalyptus fiber) further increases the challenges to structural integrity in low-basicity, low-density core structures, as these fibers are less physically entangled and more prone to cracking and tearing compared to longer standard southern or northern softwood fibers. Surprisingly, Sample 3, containing the absorbent core structure described herein (which has 32% eucalyptus fiber by weight of cellulose pulp), maintained structural core integrity during use, with only a 20% core integrity failure in the recycled liner.

[0272] High-basic-weight cellulose pulp absorbent cores with greater mass allow for more physical interweaving of fibers and are generally considered to be able to maintain structural shape. However, surprisingly, Sample 6, containing a high-basic-weight (greater than 350 gsm) cellulose pulp core with 32% eucalyptus fiber (and without an upper or lower nonwoven layer), exhibited significant structural breakage of the fiber matrix, with a core integrity failure of 32% in the recycled liner. It is believed that this level of core integrity failure in use may be unacceptable to consumers.

[0273] Unrestricted by theory, it is believed that the absorbent core structure described herein provides structural integrity through the use of an elastic upper nonwoven layer and / or lower nonwoven layer, enabling the absorption core structure to achieve a relatively low density (i.e., 0.045 g / cm³). 3 Up to 0.15 g / cm 3 The use of 32% or more short cellulose fibers. Additional features described herein, such as, for example, peripheral seals, flexural bonding channel areas, and / or structural bonding sites in the left and right lateral regions of the upper and lower nonwoven layers, can help provide additional structural integrity and reduce core tearing and / or coalescence during use.

[0274] Samples 1 through 3 were also tested to evaluate the effect of short cellulose fibers on the ability of the absorbent core structure to compress (simulating compression experienced between the wearer's legs) and return to its original state. Samples 1 through 3 were evaluated according to the wet and dry CD and MD 3-point bending method, the wet and dry coalescing compression method, and the light touch rewetting method as described herein. The results are shown in Table 5.

[0275] Table 5 :

[0276]

[0277] Sample 1, which does not contain short cellulose fibers, showed 15.5 NN. mm 2 The CD dry bending stiffness and the 30% wet recovery in the fifth cycle of wet and dry cohesive compression methods indicate that Sample 1 will be able to maintain its shape in use. The addition of eucalyptus short cellulose fibers (Samples 2 and 3) was found to have no negative impact on the ability of the articles to bend and / or compress and return to their original shape. Samples 2 and 3 were also found to maintain fluid handling properties and draw fluid deep into the absorbent core structure, as demonstrated by a light touch rewetting of 0.10 g.

[0278] It is believed that, in order to provide high body conformation capabilities, the absorbent article of this disclosure can exhibit approximately 7.0 N. mm 2 To approximately 30.0N mm 2 or approximately 10.0N mm 2 Approximately 25N mm 2 The low CD dry bending stiffness (i.e., high flexibility). Furthermore, it is believed that, in order to provide an absorbent article that can be compressed with body movement and return to its original pre-compression state against the user's body, the absorbent article of this disclosure may have approximately 1.0 N. mm to approximately 3.5N The fifth cycle wet recovery energy is mm and / or about 29% to about 40% of the fifth cycle wet recovery. The absorbent article of this disclosure also maintains good fluid handleability, delivering about 0 g to about 0.15 g of low-touch rewetting.

[0279] Combination / Example

[0280] Paragraph A. A disposable absorbent article comprising:

[0281] The absorber core structure includes:

[0282] a. An upper nonwoven layer comprising polymer fibers and having a basis weight of about 30 gsm to about 85 gsm, wherein the upper nonwoven layer includes a first side region and a laterally opposite second side region;

[0283] b. A lower nonwoven layer comprising polymer fibers, wherein the lower nonwoven layer includes a first side region and a laterally opposed second side region; and

[0284] c. An inner core layer comprising a mixture of cellulose pulp and superabsorbent particles, wherein a portion of the inner core layer is disposed between the upper nonwoven layer and the lower nonwoven layer.

[0285] The cellulose pulp contains about 25% to about 70% short cellulose fibers by weight of the cellulose pulp, wherein the short cellulose fibers have an average fiber length of less than about 2 mm, preferably about 0.3 mm to about 2 mm.

[0286] The absorber core structure has a density of approximately 0.045 g / cm³. 3 Approximately 0.15 g / cm³ 3 The average density between;

[0287] The inner core layer is contained within the upper and lower nonwoven layers by sealing a portion of the first and second side regions of the upper nonwoven layer with a portion of the first and second side regions of the lower nonwoven layer at a peripheral seal.

[0288] Paragraph B. The disposable absorbent article according to paragraph A, wherein the short cellulose fiber is selected from the group consisting of maple, oak, eucalyptus, poplar, beech, birch, paulownia, bamboo, industrial hemp fiber, acacia, wheat straw, rice straw, corn husk, and combinations thereof.

[0289] Paragraph C. The disposable absorbent article according to paragraph A or B, wherein the disposable absorbent article comprises about 15% to about 50% by weight of the inner core layer of superabsorbent particles.

[0290] Paragraph D. A disposable absorbent article according to any one of paragraphs A to C, wherein the lower nonwoven layer has a basis weight of about 7 gsm to about 40 gsm, preferably about 10 gsm to about 35 gsm, more preferably about 15 gsm to about 20 gsm.

[0291] Paragraph E. A disposable absorbent article according to any one of paragraphs A to D, wherein the absorbent article has a strength of about 7.0 N as measured by the wet and dry CD and MD 3-point bending method. mm 2 To approximately 30.0N mm 2 The CD dry bending stiffness, and the fifth cycle wet recovery, as measured by wet and dry cohesive compression methods, is between approximately 29% and approximately 40%.

[0292] Paragraph F. A disposable absorbent article according to any one of paragraphs A to E, wherein the upper nonwoven layer is a breathable bonded nonwoven, a needle-punched nonwoven, a carded nonwoven, or a spunlace nonwoven.

[0293] Paragraph G. The disposable absorbent article according to paragraphs A to F, wherein the polymer fibers of the upper nonwoven layer have a short fiber length of about 10 mm to about 100 mm.

[0294] Paragraph H. A disposable absorbent article according to paragraphs A to G, wherein the absorbent article has a dry thickness of about 2.0 mm to about 6.0 mm as measured by the wet and dry CD and MD 3-point method.

[0295] Paragraph I. The disposable absorbent article according to paragraphs A to H, wherein the polymer fiber of the upper nonwoven layer is selected from polyethylene terephthalate, polypropylene, polylactic acid, bicomponent fibers comprising polyethylene / polypropylene or polyethylene / polyethylene terephthalate, and combinations thereof.

[0296] Paragraph J. The disposable absorbent article according to paragraphs A to I, wherein the polymer fiber of the lower nonwoven layer is selected from polyethylene terephthalate, polypropylene, polylactic acid, bicomponent fibers comprising polyethylene / polypropylene or polyethylene / polyethylene terephthalate, and combinations thereof.

[0297] Paragraph K. The disposable absorbent article according to paragraphs A to J, wherein the polymer fiber of the upper nonwoven layer has a fiber diameter of about 2.0 dtex to about 10.0 dtex.

[0298] Paragraph L. The disposable absorbent article according to paragraphs A to K, wherein the polymer fibers of the lower nonwoven layer have a fiber diameter of about 1.0 dtex to about 5.0 dtex.

[0299] Paragraph M. A disposable absorbent article according to paragraphs A to L, wherein the absorbent article has a light touch rewetting capacity of 0 g to about 0.15 g as measured by the light touch rewetting method.

[0300] Paragraph N. A disposable absorbent article according to paragraphs A to M, wherein the inner core layer contains superabsorbent particles of about 20 gsm to about 125 gsm.

[0301] Paragraph O. A disposable absorbent article according to paragraphs A to N, wherein the inner core layer comprises about 125 gsm to about 350 gsm of cellulose pulp.

[0302] Paragraph P. According to the disposable absorbent article described in paragraphs A to O, the disposable absorbent article further includes a top sheet and a bottom sheet; wherein the absorbent core structure is disposed between the top sheet and the bottom sheet;

[0303] Paragraph Q. The disposable absorbent article according to paragraphs A to P, wherein at least one of the upper nonwoven layer and the lower nonwoven layer comprises a polymer selected from the group consisting of: recyclable polymer resins, biodegradable polymers, biopolymers, and combinations thereof.

[0304] Paragraph R. The disposable absorbent article according to paragraphs A to Q, wherein the polymer fiber of the upper nonwoven layer comprises about 60% to about 100% synthetic fiber and 0% to 40% regenerated cellulose fiber including rayon.

[0305] The dimensions and values ​​disclosed herein should not be construed as strictly limited to the precise numerical values ​​cited. Rather, unless otherwise specified, each such dimension is intended to represent the stated value and the range surrounding its functional equivalent. For example, a dimension disclosed as “40 mm” is intended to represent “approximately 40 mm”.

[0306] Unless expressly excluded or otherwise limited, every reference cited herein, including any cross-references or related patents or applications, is incorporated herein by reference in its entirety. Reference to any reference is not an endorsement of it as prior art to any disclosed or protected art herein, nor is it an endorsement of any such invention, either on its own or in combination with any one or more references. Furthermore, where any meaning or definition of a term in this invention conflicts with any meaning or definition of the same term in referenced documents, the meaning or definition given to that term in this invention shall prevail.

[0307] While specific embodiments of the invention have been illustrated and described by way of example, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, it is intended that all such changes and modifications falling within the scope of the invention be covered by the appended claims.

Claims

1. A disposable absorbent article, the disposable absorbent article comprising: Top film; negative; and An absorbent core structure disposed between the top sheet and the bottom sheet, wherein the absorbent core structure comprises: a. An upper nonwoven layer comprising polymer fibers and having a basis weight of 30 gsm to 85 gsm, wherein the upper nonwoven layer comprises a first side region and a laterally opposite second side region. b. A lower nonwoven layer comprising polymer fibers, wherein the lower nonwoven layer includes a first side region and a laterally opposed second side region; and c. An inner core layer comprising a mixture of cellulose pulp and superabsorbent particles, wherein a portion of the inner core layer is disposed between the upper nonwoven layer and the lower nonwoven layer. The cellulose pulp contains 25% to 70% short cellulose fibers by weight of the cellulose pulp, wherein the short cellulose fibers have an average fiber length of less than 2 mm. The absorber core structure has a density between 0.045 g / cm³. 3 and 0.15g / cm 3 The average density between; The inner core layer is contained within the upper and lower nonwoven layers by sealing a portion of the first and second side regions of the upper nonwoven layer with a portion of the first and second side regions of the lower nonwoven layer at a peripheral seal.

2. The disposable absorbent article according to claim 1, wherein the short cellulose fiber is selected from the group consisting of maple, oak, eucalyptus, poplar, beech, birch, paulownia, bamboo, industrial hemp fiber, acacia, wheat straw, rice straw, corn husk, and combinations thereof.

3. The disposable absorbent article according to claim 1 or claim 2, wherein the disposable absorbent article comprises 15% to 50% superabsorbent particles based on the weight of the inner core layer.

4. The disposable absorbent article according to any one of claims 1 to 3, wherein the lower nonwoven layer has a basis weight of 7 gsm to 40 gsm, preferably 10 gsm to 35 gsm, more preferably 15 gsm to 20 gsm.

5. The disposable absorbent article according to any one of claims 1 to 4, wherein the absorbent article has a strength between 7.0 N as measured by the wet and dry CD and MD 3-point bending method. mm to 30.0N mm 2 The CD dry bending stiffness, and the fifth cycle wet recovery, as measured by wet and dry cohesive compression methods, is between 29% and 40%.

6. The disposable absorbent article according to any one of claims 1 to 5, wherein the upper nonwoven layer is a breathable bonded nonwoven fabric, a needle-punched nonwoven fabric, a carded nonwoven fabric, or a hydroentangled nonwoven fabric.

7. The disposable absorbent article according to any one of claims 1 to 6, wherein the polymer fibers of the upper nonwoven layer have a short fiber length of 10 mm to 100 mm.

8. The disposable absorbent article according to any one of claims 1 to 7, wherein the absorbent article has a dry thickness of 2.0 mm to 6.0 mm as measured by the wet and dry CD and MD 3-point method.

9. The disposable absorbent article according to any one of claims 1 to 8, wherein the polymer fibers of at least one of the upper nonwoven layer and the lower nonwoven layer are selected from polyethylene terephthalate, polypropylene, polylactic acid, bicomponent fibers comprising polyethylene / polypropylene or polyethylene / polyethylene terephthalate, and combinations thereof.

10. The disposable absorbent article according to any one of claims 1 to 9, wherein the polymer fibers of the upper nonwoven layer have a fiber diameter of 2.0 dtex to 10.0 dtex.

11. The disposable absorbent article according to any one of claims 1 to 10, wherein the polymer fibers of the lower nonwoven layer have a fiber diameter of 1.0 dtex to 5.0 dtex.

12. The disposable absorbent article according to any one of claims 1 to 11, wherein the absorbent article has a light touch rewetting of 0 to 0.15 grams as measured by the light touch rewetting method.

13. The disposable absorbent article according to any one of claims 1 to 12, wherein the inner core layer comprises 20 gsm to 125 gsm of superabsorbent particles and 125 gsm to 350 gsm of cellulose pulp.

14. The disposable absorbent article according to any one of claims 1 to 13, wherein at least one of the upper nonwoven layer and the lower nonwoven layer comprises a polymer selected from the group consisting of: recyclable polymer resins, biodegradable polymers, biopolymers, and combinations thereof.

15. The disposable absorbent article according to any one of claims 1 to 14, wherein the polymer fiber of the upper nonwoven layer comprises 60% to 100% synthetic fiber and 0% to 40% regenerated cellulose fiber comprising rayon.

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