Multi-layered absorbent article

Abstract

An absorbent article for menstrual and / or incontinence purposes, having a unique two-layer acquisition and absorbent structure. The cover layer includes a natural material, a treated natural material, a synthetic material, or combinations thereof. The absorbent core includes an airlaid having cellulose fibers and SAP. The absorbent article includes various absorbent properties that are improved while including a reduced amount of cellulose fibers in the absorbent core.

Description

MULTI-LAYERED ABSORBENT ARTICLECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application Ser. No. 63 / 604,954, filed on December 1, 2023, the contents of which are incorporated by reference in its entirety herein.BACKGROUND

[0002] The present disclosure relates to an absorbent article for menstrual and / or incontinence purposes. Specifically, the present disclosure relates to absorbent articles such as ultra- thins or liners.

[0003] Current absorbent products can be bulky and lack flexibility or sufficient absorption properties; such deficiencies lead to discomfort for a user when wearing the absorbent product. Current absorbent products can be difficult to manufacture and / or costly, as they require multiple components often made by different manufacturers.SUMMARY

[0004] An absorbent article for menstrual or incontinence purposes is provided, such as a napkin, including a pad, liner, maxi or ultra-thin product. The absorbent article has a cover layer, and absorbent core structure, and a backsheet that is generally hydrophobic thereby preventing moisture from travelling through the absorbent article and onto the underlying garment (underwear, pants, etc. .. . ) The absorbent article optionally includes a transfer layer. In other embodiments, the properties of the transfer layer have been designed into the cover layer and / or the absorbent core. In such latter embodiments, the overall thickness of the pad is optionally reduced. In such latter embodiments, the overall thickness of at least one of the cover layer and the absorbent core is increased such that the thickness of the layer is greater than priorart products but still achieves a reduced thickness product. While such embodiments as contemplated throughout the present disclosure could be used in numerous forms to achieve a reduction in thickness, an ultra-thin or liner is preferred.

[0005] In ultra-thin embodiments, the absorbent article has a length, width and thickness, where the length is between about 160 mm to about 320 mm, and the width varies between about 70 mm to about 140mm (at its widest portion). The total thickness of the cover, the optional transfer layer, and the absorbent core, is between about 2.5 mm and about 4.0 mm, or between about 2.5 mm and about 3.5 mm, and more preferably between 2.8 mm and about 3.3 mm. The cover, the optional transfer layer, and absorbent core, has a total weight of between about 6 g and about 13 g, or between about 6.4 g and about 8.4 g, or between about 8.4 g and about 10.4 g, or between about 11 g and about 13 g.

[0006] In maxi embodiments, the absorbent article has a length, width and thickness, where the length is between about 300 mm to about 340 mm, and the width varies between about 140 mm to about 160 mm (at its widest portion). The total thickness of the cover, the optional transfer layer, and the absorbent core, is between about 5 mm and about 13.0 mm. or between about 4 mm and about 12 mm, or about 9 mm. The cover, the optional transfer layer, and absorbent core, has a total weight of between about 10 g and about 15 g, or between about 10 g and about 13 g, or between about 12 g and about 13 g.

[0007] In some embodiments, the cover layer is a spunbound or spunlace material. In some embodiments, the cover layer is imaged spunlace that is hydroentangled. In some embodiments, the cover layer has a uniquely configured image or pattern. In some embodiments, the cover layer is a hot through air (HTA) nonwoven material. Optionally, the cover layer is apertured.

[0008] The cover layer includes natural fibers, treated natural fibers (e.g., lyocell). nonwoven fibers and / or synthetic fibers. In one embodiment, the cover layer includes a blend of fibers. In some embodiments, fibers are blended together. For instance, natural fibers and / ortreated fibers are blended. In some embodiments, polypropylene, polyester, and / or polyethylene fibers are blended together. For instance, polyester and polypropylene fibers are blended, or polyethylene and polypropylene fibers are blended. In some embodiments, natural, treated natural, and / or synthetic fibers are blended. In some embodiments, hydrophilic and hydrophobic fibers are blended. Such ratios of fibers can be from about 1 :3 to about 3: 1 , respectively, or said differently, between about 25% - 35% to about 75% - 65%, and between about 65% - 75% to about 25% - 35%, respectively. In some embodiments, the ratio of fibers can be approximately even, about 1 : 1, or about 50% each.

[0009] The cover has a basis weight (gsm) of less than about 35 gsm, or between about 18 gsm and about 35 gsm, or between about 28 gsm and about 33 gsm.

[0010] An absorbent core is an airlaid structure, or optionally includes an airlaid layer that is optionally a multi-bonded airlaid composed of pulp, and SAP. Other materials are optionally included (e.g., nonwoven layers, bicomponent fibers (BICO) and / or glue). In some embodiments, the absorbent core construction further includes a binder material such that the absorbent core can be made and transported to final assembly of the absorbent article. Such binders include dispersion binders. Some dispersion binders include latex, vinyl acetate and / or ethylene. Some dispersion binders of the present disclosure are aqueous polymer dispersions. The dispersion binder is applied throughout the entirety of the absorbent core, or at least along the bottom layer and top layer.

[0011] In some embodiments, the absorbent core construction relies on hydrogen bonds to maintain the absorbent core in a unitary structure. In some embodiments, hydrogen bonds and a binder material maintain the absorbent core in a unitary structure.

[0012] Super absorbent materials such as super absorbent polymers, include but are not limited to, those commercialized by Nippon Shokubai, BASF, Evonik, and Sumitomo, such asSA55, SA60, SA65, SA65s, and SA70.

[0013] Optionally, the absorbent article includes an odor neutralizer agent that is applied and is expected to remain in the same position (applied to the airlaid). Optionally, the odor neutralizer includes baking soda. Optionally, the odor neutralizer contains one or more of absorbers, adsorbers, and perfume (e g., fragrance).

[0014] In ultra-thin embodiments, the core has a weight of between about 3.3 g and about 6 g, or between about 2.8 g and about 3.8 g, or between about 2.8 and 3.3 g, or between about 3.7 g and about 4.7 g, or between about 3.7 g and about 4.2 g, or between about 5 g and 6 g, or between about 5 and 5.5 g.

[0015] In maxi embodiments, the core has a weight of between about 7.5 g and about 12 g, or between about 8 g and about 10.5 g.

[0016] In ultra-thin embodiments, pulp or cellulose fiber material content is between about 80% and about 95% of the entire absorbent core, or between about 82% and about 92%.

[0017] In maxi embodiments, pulp or cellulose fiber material content is between about 90% and about 98% of the entire absorbent core, or about 95%.

[0018] In ultra-thin embodiments, super absorbent material comprises between about 5% and about 20% of the entire absorbent core, or between about 5% and about 10% of the entire absorbent core.

[0019] In maxi embodiments, super absorbent material comprises between about 2% and about 10% of the entire absorbent core, or about 5% of the entire absorbent core.

[0020] The binder material is between about 0.5% and about 10% of the entire absorbent core, or between about 0.5 % and about 1%.

[0021] The absorbent article includes positioning adhesive applied to the backsheet. The positioning adhesive includes multiple stripes that are covered by one or more pieces of release paper until the absorbent article is ready to be applied to a garment for use. In some embodiments, between 1 and 2 lines of adhesive are applied, such that the stripe(s) run(s) parallel to the length of the absorbent article or is(are) perpendicular to the length. In alternate embodiments,positioning adhesive is applied in a rectangular or square pattern, at least about the ends of the absorbent article.

[0022] In some embodiments, the cover layer and absorbent core are assembled using laminating adhesive. In other embodiments, laminating adhesive is not required for such assembly, rather the products are assembled via heat and / or mechanical crimping.

[0023] Embodiments of the absorbent article as taught by the present disclosure are advantageous over the prior art. For example, the absorbent article has a reduced weight as compared to prior art absorbent articles. Surprisingly, the reduced weight is driven by a reduction in the weight of the cellulose fibers (e.g., fluff pulp) in the core of between about 0.5 g to about 1.0 g over current ultra-thin and maxi products. Such reduction in weight in combination surprisingly provides an absorbent product with improved p-time.

[0024] Additionally, the cover of the present disclosure has an increased thickness. The increased thickness surprisingly provides an absorbent article with improved p-time.

[0025] Additionally, absorbent products of the present disclosure including an increased thickness cover layer and a reduced weight core have improved p-time.

[0026] The p-time for absorbent articles according to the present disclosure is decreased thereby moving fluid away from the cover layer more quickly and into the absorbent core, thereby providing improved dryness to the user. Surprisingly, the p-time is improved despite having a cover layer that is thicker than existing cover layers and an absorbent core that is thinner than existing absorbent cores.

[0027] In some embodiments, the mean p-time is less than about 11 seconds, or less than 10.5 seconds, or between about 6.9 seconds and 10.5 seconds.

[0028] The absorbent article of the present disclosure has a mean rewet that is less than about 0.7 g, or less than 0.66 g, or greater than 0 and less than 0,7 g, or greater than 0 and less than about 0.66 g, or between about 0.55 g and about 0.7 g, or between about 0.55 g and about 0.66 g.

[0029] The absorbent article of the present disclosure has an improved mean absorbency of at least 88 g, or between 88 g and 140 g, or between 88 g and about 110 g, or between about 88 g and about 90 g, or between about 105 g and about 140 g.

[0030] The absorbent article optionally has a simplified manufacturing process. In some embodiments, the absorbent article does not require a transfer layer. As such, only three layers (cover, absorbent core, backsheet) are required. Such simplified structure is advantageous from a cost perspective.

[0031] According to an embodiment of the present disclosure, an absorbent article includes a length, a width, and a thickness, a cover layer, an absorbent core, and a backsheet layer. The absorbent article includes a cover layer having a body facing surface and a lower cover surface opposite to the body facing surface. The cover layer includes cotton fibers. The absorbent article includes a core adjacent to the lower cover surface. The absorbent core includes an airlaid having cellulose fibers and SAP. The cellulose fibers have a weight between about 2.8 g and about 5.5 g. The backsheet layer includes a backsheet upper surface and a garment-facing surface opposite the backsheet upper surface. The backsheet upper surface is at least partially adjacent the absorbent core.

[0032] In some embodiments, the absorbent article has a p-time of between about 6.9 s and about 10.4 s.

[0033] In some embodiments, the absorbent article has a GATS absorbency acquisition rate of between about 0.09 g of water per second and about 0.10 g of water per second.

[0034] In any of the embodiments contemplated herein, the absorbent article may be an ultra-thin article.

[0035] In any of the embodiments contemplated herein, the absorbent article has a p-time of between about 6.9 s and about 9.9 s.

[0036] In any of the embodiments contemplated herein, the absorbent article has a mean rewet of between about 0.55 g and about 0.66 g.

[0037] In any of the embodiments contemplated herein, the absorbent article is a regular ultra-thin. The regular ultra-thin includes a weight of cellulose fibers between about 2.5 g and about 3.3 g.

[0038] In any of the embodiments contemplated herein, the absorbent article is a super long ultra-thin. The super-long ultra-thin includes a w eight of cellulose fibers betw een about 3.7 g and about 4.3 g.

[0039] In any of the embodiments contemplated herein, the absorbent article is an overnight ultra-thin. The overnight ultra-thin includes a weight of cellulose fibers between about 5 g and about 5.5 g.

[0040] In any of the embodiments contemplated herein, the absorbent article has a ratio of cellulose material to SAP of between about 4: 1 and about 6: 1.

[0041] In any of the embodiments contemplated herein, the absorbent core includes about 82% to about 92% cellulose material.

[0042] In any of the embodiments contemplated herein, the absorbent core includes between about 8% and about 18% SAP.

[0043] The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. For example, aspects and / or embodiments of the present disclosure may include any one or more of the individual features or elements disclosed above and / or below alone or in any combination thereof. These features and elements as well as the operation thereof will become more apparent in light of the followingdescription and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting.BRIEF DESCRIPTION OF THE DRAWINGS

[0044] FIG. 1 shows an illustration of a top view of an embodiment of the present disclosure;

[0045] FIG. 2 shows an illustration of a top view of a regular absorbent article embodiment of the present disclosure:

[0046] FIG. 3 shows an illustration of a schematic view of an embodiment of the absorbent article of the present disclosure; and

[0047] FIG. 4 shows an illustration of a schematic view of an embodiment of the absorbent article of the present disclosure.DETAILED DESCRIPTION

[0048] As exemplified in FIGS. 1 - 4 . an absorbent article (10) is provided. The absorbent article has a length (14), a width (15), and a thickness (16). and generally includes a top-most (or body-facing) surface (11), often referred to as a cover layer (11). As exemplified in FIGS. 3-4, the absorbent article (10) has a backsheet (or barrier layer) (18) opposite the cover layer (11), and generally facing a garment worn by the user. The absorbent article (10) has an absorbent core (20) structure between the cover layer (11) and the backsheet (18). Optionally, absorbent article (10) has a transfer layer (25) between the cover layer (11) and absorbent core (20).

[0049] The absorbent article (10) has many shapes, but as shown and preferably for at least ultra-thin products and maxi products, a dog-bone, peanut-shape, hourglass, and / or barbell shape is provided. Alternative shapes include generally cylindrical, elliptical, thong-shaped, and / or hybrids thereof.

[0050] Optionally, absorbent articles (10) included colored portions (24) to denote absorbent areas, enhance the perception of depth of the absorbent article (10), and / or assist in masking fluids that ingratiate the absorbent article (10). Colored portions (24) are on the upper surface (12) of the cover layer (11), lower surface (13) of the cover layer (1 1), or on / within the absorbent core (20). Colored portions (24) can be varying colors but are preferably a darker color that is easier to see and optionally masks bodily discharge. Such colors are red, blue, violet, and / or green.

[0051] The cover layer (11) has a body facing surface (12) and a lower cover surface (13) opposite the body facing surface (12). The body facing surface (12), when used, is directed towards the body of a user such that the body facing surface (12) is at least partially in contact with the user, or at minimum, is the first portion of the absorbent article (10) that is ingratiate with bodily discharge such as fluid. Such fluid includes, for example, urine and / or menses.

[0052] In some embodiments, the cover layer (11) is a spunbound or spunlace material. The cover layer (11) is optionally apertured. The cover layer (11) includes, natural (e.g., cotton fibers, hemp fibers, those derived from wood and grass such as birch, oak, pine, bamboo, etc.), treated natural fibers (e.g., lyocell fibers such as those sold under the name TENCEL and / or VEOCEL by LENZING), nonwoven fibers and / or synthetic fibers. The cover (11) is optionally a treated natural fiber such as lyocell, where such lyocell fiber is optionally treated to be hydrophobic (e.g., VEOCEL). Some treated natural fibers include treatments that biodegrade (e.g., N-methylmorpholine N-oxide, “NMMO”) with the natural fiber such that the fiber is biodegradable and / or compostable. The cover layer (11) optionally has bicomponent fibers that are PE / PP.

[0053] In one embodiment, the cover layer (11) includes 100% of a single type of fiber(e.g., 100% cotton fiber, 100% lyocell fiber, 100% nonwoven fiber, 100% synthetic fiber), and optionally a small percentage of fiber finish. In an alternative embodiment, the cover layer (11) includes a blend of fibers (e.g., natural fibers, treated natural fibers such as lyocell, and / ornonwoven fibers, and / or synthetic fibers). In some embodiments, polypropylene, polyester, and / or polyethylene fibers are blended together. For instance, polyester and polypropylene fibers are blended, or polyethylene and polypropylene fibers are blended. Such ratios of fibers can be from about 1 :3 to about 3: 1, respectively, or said differently, between about 25% - 35% to about 75% - 65%, and between about 65% - 75% to about 25% - 35%, respectively. In some embodiments, the ratio of fibers can be approximately even, about 1: 1, or about 50% each.

[0054] Optionally, the first fiber is a first lyocell fiber and the second fiber is a second lyocell fiber that is different from the first lyocell fiber. Optionally, the first fiber is a first natural fiber and the second fiber is a second natural fiber that is different from the first natural fiber. Optionally, the first fiber is a treated natural fiber and the second fiber is an untreated natural fiber. Optionally, the first fiber is an untreated natural fiber and the second fiber is a treated natural fiber.

[0055] In some embodiments, the cover layer (11) has a basis weight that is between about 18 gsm and about 50 gsm, or between about 18 gsm and about 35 gsm, or between about 27 gsm and 33 gsm. or between about 28 gsm and about 32 gsm, or between about 29 gsm and about 31 gsm, or about 30 gsm.

[0056] In some embodiments, the cover layer (11) is an imaged spunlace that is hydroentangled. In some embodiments, the cover layer (11) has a uniquely configured image or pattern. Cover materials are sold by manufacturers such as Glatfelter, Suominen, Fitesa, and Shalag.

[0057] In some embodiments, the cover layer (11) is embossed. The embossing has one or more protrusions (26) separated by one or more channels (27). The protrusions (26) are raised on the body facing surface (12) with respect to a cover layer base height. In some embodiments, the embossing forms a pattern. In some embodiments, the cover layer (11) has an embossed pattern, the one or more protrusions (26) and the one or more channels (27) in such embossed pattern being a repeating pattern across at least a portion of the absorbent article (10), such as afirst end region (43), a second end region (44), and / or a central region (45), and / or a first lateral region (46), a central length region (48), and / or a second lateral region (47) that is opposite the first lateral region (46). In some embodiments, the embossed pattern is a repeating pattern across substantially the entirety of the absorbent article (10).

[0058] In some embodiments, the cover layer (1 1) has protrusions (26) and channels (27) forming an embossed pattern that is optionally a repeating pattern across at least a portion of the absorbent article (10), such as a first end region (43), a second end region (44), and / or a central region (45), and / or a first lateral region (46), a central length region (48), and / or a second lateral region (47) that is oppositeto a respective opposite region. In some embodiments, the pattern is a repeating pattern across substantially the entirety of the absorbent article (10). The protrusions (26) in the cover layer (11) are separated by channels (27) between about 2 mm and about 10 mm, or between about 2 mm about 5 mm. The protrusions (26) each have a protrusion height of between about 0.1 mm and about 1 mm. Each side (49) of the protrusions (26), or in the exemplary embodiment.) has a protrusion length (50) of between about 5 mm and about 80 mm. or between about 5 mm and about 10 mm, or between about 60 mm and about 80 mm. The width / diameter (39) of each protrusion (26) is between about 2 mm and about 20 mm, or between about 5 mm and about 10 mm.

[0059] The absorbent core (20) is an airlaid structure, wherein material is deposited onto a substrate. The absorbent core (20) has an upper core surface (21) that is adjacent the lower cover surface (13), and a lower core surface (23) that is adjacent the backsheet upper surface (17). Absorbent core (20) structures optionally can be purchased from manufacturers such as EAM and Glatfelter.

[0060] In absorbent core (20) embodiments having fiber material and super absorbent material, the ratio of cellulose fiber (e.g., fluff pulp) to super absorbent material is between about 6: 1 and about 4: 1. Cellulose fiber (e.g., fluff pulp) material content is between about 80% and about 98% of the entire absorbent core (20), or between about 82% and about 95%. Superabsorbent material comprises between about 5% and about 20% of the entire absorbent core (20), or between about 8% and about 18% of the entire absorbent core (20).

[0061] The absorbent core (20) optionally includes binder material (e.g., glue) that is between about 0.5% and about 1% of the total weight of the absorbent core (20).

[0062] Glue is used as a binder material for the absorbent core (20). One type of binder material is a dispersion binder. The dispersion binder is latex, vinyl acetate and / or ethylene. Some dispersion binders of the present disclosure are aqueous polymer dispersions.

[0063] Pulp in the absorbent core (20) is treated or untreated, or a mixture of both treated and untreated. Such pulp is sold by, for example, manufacturers GP Cellulose or International Paper.

[0064] Cellulose fibers, and also bicomponent fibers (e.g.. PE-PET) are sold by. for example. GP Cellulose or International Paper.

[0065] Super absorbent material used in the absorbent core (20) is sold by Sumitomo. Nippon Shokubai, BASF, and Evonik. For example, some super absorbent polymer grades sold by Sumitomo include SA55, SA60. SA65, SA65s, SA70. Super absorbent material is between about 25% and about 40% of the total weight of the absorbent core (20).

[0066] The backsheet (18) has a backsheet upper surface (17) that is opposite the backsheet garment facing surface (19). The backsheet upper surface (17) is adjacent the absorbent core (20) and more specifically, the lower core surface (23) of the absorbent core (20). The backsheet garment facing surface (19) is typically positioned adjacent the undergarment worn by a user. The backsheet garment facing surface (19) optionally has releasable adhesive enabling temporary attachment to the undergarment, such that the backsheet garment facing surface (19) can be separated from the undergarment when absorbent article (10) needs to be replaced.

[0067] In some embodiments, one or more wings (22) extend outwardly from the lateral edges (42) and are attachable to the undergarment. The wings (22) have a releasable adhesiveenabling the wings (22) to temporarily adhere to the undergarment such that the wings (22) can be separated from the undergarment when absorbent article (10) needs to be replaced. In embodiments having releasable adhesive on the backsheet garment facing surface (19) and / or wings (22), the releasable adhesive is covered by release paper and / or an overwrap to keep the absorbent article (10) from sticking to other items prior to use.

[0068] The absorbent article (10) has a length (14), width (15) and thickness (16) (note: while shown inf FIG. 3 in an exploded view, the thickness (16) regards the thickness of the absorbent article (10) when assembled and ready for use by a consumer), where the length (14) is between about 160 mm to about 340 mm, and the width (15) varies between about 70 mm to about 160 mm (between its nanowest portion (15a) and its widest portion (15b)). In ultra-thin embodiments, the total thickness (16) of the cover (11), the optional transfer layer (25). the absorbent core (20). and the backsheet (18) is between about 2.5 mm and about 4.0 mm, or between about 2.5 mm and about 3.5 mm, and more preferably between 2.8 mm and about 3.3 mm. In maxi embodiments, the total thickness of the cover (11), the optional transfer layer (25). and the absorbent core (20), is between about 5 mm and about 13.0 mm, or between about 4 mm and about 12 mm, or about 9 mm. The cover (11), the optional transfer layer (25) the absorbent core (20), and the backsheet (18) has a total weight of between about 6 g and about 15 g, or between about 6.4 g and about 8.4 g, or between about 8.4 g and about 10.4 g, or between about 11 g and about 13 g. or between about 10 g and about 13 g, or between about 12 g and about 13 g-

[0069] The absorbent article (10) includes ultra-thin and maxi embodiments having varying sizes - regular, super, long, extra-long, etc.. Such ultra- thin and maxi embodiments include varying purposes such as those for daily use and those for overnight use.

[0070] Procedure for Measuring Fluid Penetration Time (P-time)

[0071] Fluid Penetration Time is measured by placing a sample to be tested under a Fluid Penetration Test orifice plate. The orifice plate consists of a 7.6 cm X 25.4 cm plate of 1.3 cmthick polycarbonate with an elliptical orifice in its center. The elliptical orifice measures 3.8 cm along its major axis and 1.9 cm along its minor axis. The orifice plate is arranged on the product sample to be tested at a corresponding location on the absorbent article from which the 37 mm X 37 mm test specimen. The longitudinal axis of the elliptical orifice is arranged parallel to the longitudinal axis of the product to be tested.

[0072] SPTF 1C (non-Newtonian Synthetic Menstrual Fluid) was used for the following procedure.

[0073] Weigh and add 15.7 g of Sodium Chloride (USP grade or equivalent) and 0.16 g of FD&C Blue Dye #1 from BF Goodrich, in a 1 liter volumetric flask. Add distilled water to dissolve, then fill-up to volume. Insert the magnetic stirrer and mix for 20 minutes on the stirring plate.

[0074] An automatic pipette or equivalent containing 7 ml of test fluid is held over the orifice plate such that the exit of the syringe is approximately 3 inches above the orifice. The syringe is held horizontally, parallel to the surface of the test plate. The fluid is then expelled from the syringe at a rate that allows the fluid to flow in a stream vertical to the test plate into the orifice and a stopwatch is started when the fluid first touches the sample to be tested. The stopwatch is stopped when a portion of the surface of the sample first becomes visible above the remaining fluid within the orifice. The elapsed time on the stopwatch is the Fluid Penetration Time in seconds. The average Fluid Penetration Time (FPT) is calculated from taking the average of three product samples.

[0075] Procedure for Measuring Rewet Potential

[0076] The three product samples used for the Fluid Penetration Time (FPT) procedure described above are used for the Rewet Potential test described below.

[0077] The rewet potential is a measure of the abi li ty of an absorbent article to hold liquid within its structure when an absorbent article contains a relatively large quantity of liquid and issubjected to external mechanical pressure. The rewet potential is determined and defined by the following procedure.

[0078] The apparatus for the Rewet Potential test is the same as that set forth above with regard to the FPT test and further includes a quantity of 2 inch X 4 inch rectangles of Ahlstrom 631 Filter Paper from Ahlstrom Group Helsinki, Finland, Whatman 4 Filter Paper from Whatman, Inc. Clifton, NJ or equivalent and a weighing machine or balance capable of weighing to an accuracy of + / -0.001 g, a quantity of said Whatman paper, a standard weight of 2.22 kg (4.8 pounds) having dimensions 5.1 cm (2 inches) by 10.2 cm (4.0 inches) by approximately 5.4 cm (2. 13 inches) which applies a pressure of 4. 14 kPa (0.6 psi) over the 5. 1 by 10.2 cm (2 inches by 4 inches) surface.

[0079] For purposes of the test procedure set forth herein, the same three product samples used for the FPT test should be used for the Rewet Potential Test. After the test fluid is applied within the orifice plate in the FPT test described above, and as soon as the cover layer (11) of the product sample first appears through the top surface of the fluid, the stopwatch is started, and an interval of 5 minutes is measured.

[0080] After 5 minutes have elapsed, the orifice plate is removed, and product sample is positioned on a hard level surface with the cover layer facing upwards.

[0081] A fifteen-layer stack of the pre- weighed filter paper is placed on and centered over the wetted area and the standard 2.22 kg weight is placed on top of the filter paper. The filter paper and the weight are arranged over the absorbent article (10) such that they are centered over the area to which the fluid was applied. The filter paper and the weight are arranged such that their longer dimensions are aligned with the longitudinal direction of the product. Immediately after placing the paper and weight on the product, the stopwatch is started and after a 3-minute interval has elapsed the standard weight and filter paper are quickly removed. The wet weight of the filter paper is measured and recorded to the nearest 0.001 grams. The rewet value is thencalculated as the difference in grams between the weight of the wet 15 layers of filter paper and the dry 15 layers of filter paper.

[0082] The measurement should have at least three replicates and, if necessary, the weight is wiped clean before each run. The average rewet value (R) is then calculated from the three measured values and this rewet value (R) may then be used in the Absorbency Index (Al) equation set forth above.

[0083] Procedure for Measuring the Average Thickness of a Absorbent Article

[0084] The apparatus required to measure the thickness of the absorbent article (10) sample is a footed dial (thickness) gauge with stand, available from Ames (e.g., model LG1820- 1-04 or equivalent), with a 57 g dead weight, a foot surface area of 1.129" diameter contact (1 sq. in.) at a pressure of 0.1 psig and a readout accurate to 0.001". A digital type apparatus is preferred. If the absorbent article (10) sample is individually folded and wrapped, the sample is unwrapped and carefully flattened by hand. The release paper is removed from the absorbent article (10) sample and it is repositioned back gently across the positioning adhesive lines so as not to compress the sample, ensuring that the release paper lies flat across the absorbent article (10) sample. Flaps (if any) are not considered when taking the thickness.

[0085] Release paper is placed under the foot of the thickness gauge. The gauge is then re-zeroed (e.g., tared) by removing the thickness of the release paper from the measurements. The gauge should read 0.00 mm (or 0.000"). The release paper is repositioned properly on the adhesive strip of the gauge so that there are no folds in the release paper. The foot of the gauge is raised, and the absorbent article (10) sample is placed on the anvil such that the foot of the gauge is approximately centered on the location of interest on the product sample. When lowering the foot, care must be taken to prevent the foot dropping onto the absorbent article (10) sample or undue force being applied. A load of 0.1 p.s.i.g. is applied to the absorbent article (10) sample and the read out is allowed to stabilize for approximately 3 seconds. The thicknessreading is then taken to the nearest 0.02 mm (or 0.001”). This procedure is repeated for at least three absorbent article (10) samples and the average thickness is then calculated.

[0086] Procedure for Measuring Average Absorbent Capacity (AC)

[0087] The absorbent article (10) samples were further tested to determine the average absorbent capacity (AC) of the absorbent article (10) samples. The test method for determining the average absorbent capacity (AC) is set forth below.

[0088] At least three new absorbent article (10) samples are required to the conduct the average absorbent capacity test described below.

[0089] The average absorbent capacity test is conducted on the product sample. A 1% saline solution is prepared at 23 degrees Celsius, plus or minus 1 degree Celsius. The Total Absorbent Capacity (“AC”) is the weight of the wet absorbent article (10) sample minus the dry absorbent article (10) sample. To perform the AC test, the absorbent article (10) sample wrapper is removed (if any). If the absorbent article (10) sample is folded, flatten-out the product sample as much as possible. The absorbent article (10) sample is then weighed after the scale is property tared. The weight of the absorbent article (10) sample in the dry state is then recorded.

[0090] The absorbent article (10) sample is submerged in a saline solution (1%) for 10 minutes, and then hung so that saline can freely drip for 2 minutes. The weight of the wet absorbent article (10) sample is then recorded.

[0091] Test Method: Protocol for Gravimetric Absorption Testing System (GATS)

[0092] GATS uses a patent-based method to reliably determine absorption characteristics. By employing a sensitive scale, slide, and software, the GATS can run either horizontal or vertical absorption studies by manipulating test plates. Either or both the capillary and structural liquid intake of a desired substrate can be assessed by GATS. The GATS is commercially available from MK Systems.

[0093] The GATS is widely used in the many industries, including nonwoven, tissue, paper towel, textile, and powder based areas. Any solid material that absorbs liquid can bemeasured with the GATS, using a method that takes user variability out of testing. After each test has been completed, data is then downloaded to a PC. The liquid source is automatically refilled.

[0094] Briefly, the GATS monitors the rate at which a liquid is absorbed onto a test plate. Tests are started either by solenoid action or by the placement of a sample onto the plate. An internal microprocessor takes several readings of the scale's output every second. The test stops when the flow rate drops below a predetermined rate or a predetermined time.

[0095] Typically, the test plate is attached to a vertical leveling mechanism. This prevents the formation of excess hydrostatic head during a test. The test plate is lowered at the same rate at which the liquid level in the reservoir drops. This eliminates the effects of gravity, providing a truer profile of the material's absorptive characteristics. The balance is very accurate (+ / -0.001 g). This accuracy and precision provides the necessary discrimination for an accurate profiling of the absorbency of a given material.

[0096] Key External References Pertaining to the GATS System.

[0097] The American Society for Testing and Materials (ASTM) actually suggests using the GATS for standard absorption testing. A key ASTM reference is: American Society for Testing and Materials (ASTM) D 5802-95, Standard Test Method for Sorption of Bibulous Paper Products (Sorption Rate and Capacity Using Gravimetric Principles). Test method ASTM D5802-95 was followed, except as noted on the next page.

[0098] Modifications for the Study of Rate of Absorbency by Absorbent Articles.

[0099] The dry mass of the absorbent article (10) is measured using a tared scale.

[0100] All tests were made at zero hydrostatic head, which means that the test stopped automatically when the absorbent article (10) was saturated and did not absorb fluid further. The fluid used was distilled water. The fluid was allowed to be absorbed by the test specimen.

[0101] The tests were performed on GATS with the absorbent article (10) placed cover side down over the orifice of the GATS system. No pressure was applied such that the test specimen could expand during absorption of fluid.

[0102] The new regular [sized liner] ultra-thin absorbent article (10) samples as taught by the present disclosure, as tested by the above-noted methods, having similar overall length (14) and width (15) dimensions as current control regular [sized] ultra-thin samples. Thirty samples of current product and new absorbent article (10) samples were tested for P-time and rewet.

[0103] With similar overall size, such absorbent article (10) samples of the present disclosure achieved improved P-time, while having a lower absorbent core (20) weight. The standard deviation for P-time on the control regular ultra-thin absorbent article (10) sample was 2.028, and the standard deviation for P-time on the new regular ultra-thin absorbent article (10) samples was between 1.695 and 2.574.

[0104] With similar overall size, such absorbent article (10) samples of the present disclosure achieved improved absorbency while having a lower absorbent core (20) weight. Regular sized ultra-thin absorbent article (10) samples of the present disclosure have an absorbency of between about 88.789 g and about 89.955 g. Control (current) regular ultra-thin absorbent article (10) samples have an absorbency of between about 83.337 g.

[0105] Five absorbent article (10) samples of regular ultra-thin products were tested under the GATS procedure and have an average acquisition rate of 0.0975 g of water per second, and an average absorbent capacity of 33.37 g. The absorbent articles (10) of the present disclosure have a GATS average acquisition rate of between about 0.09 g of water per second and about 0. 1 g of water per second. The absorbent articles (10) of the present disclosure have a GATS average absorbent capacity of betw een about 33 g and about 34 g.

[0106] In one embodiment, an airlaid absorbent article (10) having a length (14), a width(15), and a thickness (16), comprises: a cover layer (11) having a body facing surface (12) and a lower cover surface (13) opposite to the body facing surface (12); and an absorbent core (2)adjacent to the lower cover surface (13), the absorbent core (20) including cellulose fibers (e.g., fluff pulp) and SAP; a backsheet layer (18) having a backsheet upper surface (17) and a garmentfacing surface (19) opposite the backsheet upper surface (17). The absorbent article (10) has a p-time of between about 6.9 s and about 10.4 s. The absorbent article (10) has a GATS absorbency acquisition rate of between about 0.09 g of water per second and about 0.10 g of water per second.

[0107] The terms ‘'substantially”, '‘generally” and / or “about” as contemplated herein are used with the appreciation that small variations in dimensions are within the present disclosure. Such small variations can include variations due to manufacturing tolerances and / or expansion / contract! on and or wear of parts subjected to varying conditions (e.g., pressure, force, temperature, etc.), up to and including a 10% variance of the nominal dimension.

[0108] While the principles of the disclosure have been described above in connection with specific apparatuses and methods, it is to be clearly understood that this description is made only by way of example and not as limitation on the scope of the disclosure. Specific details are given in the above description to provide a thorough understanding of the embodiments. However, it is understood that the embodiments may be practiced without these specific details.

[0109] It is noted that the embodiments may be described as a process which is depicted as a flowchart, a flow diagram, a block diagram, etc. Although any one of these structures may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be rearranged. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc.

[0110] The singular forms "a," "an," and "the" refer to one or more than one, unless the context clearly dictates otherwise. For example, the term "comprising a specimen" includes single or plural specimens and is considered equivalent to the phrase "comprising at least one specimen." The term "or" refers to a single element of stated alternative elements or a combination of two or more elements unless the context clearly indicates otherwise. As usedherein, "comprises" means "includes." Thus, "comprising A or B," means "including A or B, orA and B," without excluding additional elements.

[0111] It is noted that various connections are set forth between elements in the present description and drawings (the contents of which are included in this disclosure by way of reference). It is noted that these connections are general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. Any reference to attached, fixed, connected or the like may include permanent, removable, temporary, partial, full and / or any other possible attachment option.

[0112] No element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112(f) unless the element is expressly recited using the phrase "‘means for.” As used herein, the terms “comprise”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0113] While various inventive aspects, concepts and features of the disclosures may be described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects, concepts, and features may be used in many alternative embodiments, either individually or in various combinations and sub-combinations thereof. Unless expressly excluded herein all such combinations and sub-combinations are intended to be within the scope of the present application. Still further, while various alternative embodiments as to the various aspects, concepts, and features of the disclosures— such as alternative materials, structures, configurations, methods, devices, and components, and so on— may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readilyadopt one or more of the inventive aspects, concepts, or features into additional embodiments and uses within the scope of the present application even if such embodiments are not expressly disclosed herein. For example, in the exemplary embodiments described above within the Detailed Description portion of the present specification, elements may be described as individual units and shown as independent of one another to facilitate the description. In alternative embodiments, such elements may be configured as combined elements. It is further noted that various method or process steps for embodiments of the present disclosure are described herein. The description may present method and / or process steps as a particular sequence. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps descnbed. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible. Therefore, the particular order of the steps set forth in the description should not be construed as a limitation.

Claims

What is claimed is:

1. An absorbent article having a length, a width, and a thickness, comprising: a cover layer having a body facing surface and a lower cover surface opposite to the body facing surface, the cover layer comprising cotton fibers; and an absorbent core adjacent to the lower cover surface, the absorbent core comprising: an airlaid comprising cellulose fibers and SAP, the cellulose fibers having a weight between about 2.8 g and about 5.5 g; and a backsheet layer having a backsheet upper surface and a garment-facing surface opposite the backsheet upper surface; wherein the absorbent article has a p-time of between about 6.9 s and about 10.4 s; and wherein the absorbent article has a GATS absorbency acquisition rate of between about 0.09 g of water per second and about 0. 10 g of water per second.

2. The absorbent article according to claim 1, wherein the absorbent article is an ultra-thin article.

3. The absorbent article according to claim 2, wherein the absorbent article has a p-time of between about 6.9 s and about 9.9 s.

4. The absorbent article according to claim 1. wherein the absorbent article has a mean rewet of between about 0.55 g and about 0.66 g.

5. The absorbent article according to claim 2, wherein the absorbent article is a regular ultra-thin, wherein the weight of the cellulose fibers is between about 2.5 g and about 3.3 g.

6. The absorbent article according to claim 2, wherein the absorbent article is a super long ultra-thin, wherein the weight of the cellulose fibers have is between about 3.7 g and about 4.3 g.

7. The absorbent article according to claim 2, wherein the absorbent article is an overnight ultra-thin, wherein the w eight of the cellulose fibers is between about 5 g and about 5.5 g.

8. The absorbent article according to claim 1, wherein the thickness is between about 2.8 and about 3.3 mm.

9. The absorbent article according to claim 1, wherein a ratio of cellulose material to SAP is between about 4: 1 and about 6: 1.

10. The absorbent article according to claim 1 , wherein the absorbent core comprises between about 82% and about 92% cellulose material.

11. The absorbent article according to claim 1, wherein the absorbent core comprises between about 8% and about 18% SAP.

12. An absorbent article according to any of the preceding claims, having a length (14), a width (15), and a thickness (16), comprising: a cover layer (11) having a body facing surface (12) and a lower cover surface (13) opposite to the body facing surface (12), the cover layer comprising cotton fibers; and an absorbent core (20) adjacent to the lower cover surface (13). the absorbent core (20) comprising: an airlaid comprising cellulose fibers and SAP. the cellulose fibers having a weight between about 2.8 g and about 5.5 g; and a backsheet layer (18) having a backsheet upper surface (17) and a garment-facing surface (19) opposite the backsheet upper surface (17); wherein the absorbent article (10) has a p-time of between about 6.9 s and about 10.4 s: and wherein the absorbent article (10) has a GATS absorbency acquisition rate of between about 0.09 g of water per second and about 0.10 g of water per second.

13. The absorbent article (10) according to any of the preceding claims, wherein the absorbent article (10) is an ultra-thin article.

14. The absorbent article (10) according to any of the preceding claims, wherein the absorbent article (10) has a p-time of between about 6.9 s and about 9.9 s.

15. The absorbent article (10) according to any of the preceding claims, wherein the absorbent article (10) has a mean rewet of between about 0.55 g and about 0.66 g.

16. The absorbent article (10) according to any of the preceding claims, wherein the absorbent article (10) is a regular ultra-thin, wherein the weight of the cellulose fibers is between about 2.5 g and about 3.3 g.

17. The absorbent article (10) according to any of the preceding claims, wherein the absorbent article (10) is a super long ultra-thin, wherein the weight of the cellulose fibers have is between about 3.7 g and about 4.3 g.

18. The absorbent article (10) according to any of the preceding claims, wherein the absorbent article (10) is an overnight ultra-thin, wherein the weight of the cellulose fibers is between about 5 g and about 5.5 g.

19. The absorbent article (10) according to any of the preceding claims, wherein the thickness (16) is between about 2.8 and about 3.3 mm.

20. The absorbent article (10) according to any of the preceding claims, wherein a ratio of cellulose material to SAP is between about 4: 1 and about 6: 1.

21. The absorbent article (10) according to any of the preceding claims, wherein the absorbent core (20) comprises between about 82% and about 92% cellulose material.

22. The absorbent article (10) according to any of the preceding claims, wherein the absorbent core (20) comprises between about 8% and about 18% SAP.

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