RU2810779C2 - Absorbent product and use of non-woven material in absorbent product - Google Patents

Abstract

FIELD: absorbent products.

SUBSTANCE: invention is related to an absorbent article (10, 20, 300, 500, 600) containing an absorbent core (101, 501, 60) located between a liquid-permeable top sheet (520, 620) and a liquid-impermeable bottom sheet (521, 621), and a receiving distribution layer (522, 622) located between said top sheet (520, 620) and said absorbent core (101, 501, 601), wherein the absorbent core (101, 501, 601) contains an absorbent material selected from group consisting of cellulose fibres, superabsorbent polymers and combinations thereof, wherein said absorbent core (101, 501, 601) comprises at least one interconnected channel (106) free of said absorbent material, said channel (106) having a length, extending along the longitudinal axis (48), and the absorbent core (101, 501, 601) having a length extending along the specified longitudinal axis (48), and the length of the specified channel (106) is from 10% to 95% of the length of the specified absorbent core (101, 501, 601).

EFFECT: according to the invention, the receiving distribution layer (522, 622) contains a layer of spunbond and/or carded nonwoven material comprising synthetic fibres, wherein said synthetic fibres are contained in an amount greater than 80 wt.% relative to the weight of the specified receiving distribution layer (522, 622), wherein said receiving distribution layer (522, 622) has a base weight of from 10 to 50 g/m².

15 cl, 31 dwg, 7 tbl

Description

Field of technology to which the invention relates

This invention relates to the field of technology related to absorbent personal care products. In particular, the present invention relates to an absorbent core that can be used in an article to absorb body fluids and exudates, such as urine and feces, or blood, menstrual fluid and vaginal fluids. More particularly, the present invention relates to absorbent garments such as disposable diapers or absorbent panties, disposable diapers or incontinence panties that are configured to collect and contain fecal matter and avoid leakage, or sanitary napkins or pads that are configured to collect and contain blood , menstrual flow, urine, vaginal fluids and avoid leaks.

State of the art

The invention relates to an absorbent core for an absorbent article, in particular for personal care products, to absorbent articles containing said absorbent core, and to methods for producing said absorbent core. In particular, it relates to cores containing one or more channels inside.

For a long time, the absorbent core has been the subject of significant improvement and innovative developments to overcome problems such as improved absorption and distribution of liquids, as well as comfort, and the need for further improvement still exists. Such needs are always present among today's demanding consumers. The following description provides some important information related to this topic.

EP 1077052 A1 and EP 1078617 A2 disclose a sanitary napkin that undergoes controlled deformation in response to lateral compression during use. This sanitary napkin has preferential bending zones along the longitudinal axis formed by perforating, scoring, scoring or embossing.

EP 1959903 B1 discloses a urological pad having two fold lines dividing the absorbent core material into a central portion and two longitudinal side portions for better fit to the user's body. Fold lines are created by the compression process of the absorbent material.

EP 2211808 B1 discloses an absorbent core consisting of an upper absorbent core and a lower absorbent core. The upper absorbent core includes folding points that allow the absorbent core to assume a predetermined three-dimensional shape under pressure in the transverse direction. These fold points are cuts or compression lines that do not extend through the entire top core.

EP 1349524 B1 discloses a sanitary napkin comprising at least one fold line defining a central region and two lateral regions allowing the size of the sanitary napkin to be adjusted by folding the sanitary napkin along the fold line. These fold lines are embossing lines.

EP 1267775 B1 discloses a sanitary napkin that conforms to the boundaries of the body. This sanitary napkin contains a front wide part and a back narrow part and at least two fold lines pre-laid along the upper or lower surface of the narrow part. The fold lines can be selected from mechanically pressed lines, chemically bonded line-forming components, thermally formed lines, laser formed lines, glued lines and/or mechanical vibration formed lines.

EP1088536 A2 discloses a sanitary napkin provided with folds allowing the sanitary napkin to be adapted to fit a user's underwear.

US Pat. No. 5,756,039 A discloses an absorbent core comprising individual segments that can be independently replaced by a lifting member. This lifting element ensures that the top layer conforms to the user's body.

US 2006/0184150 A1 discloses a variable flexibility absorbent core that functions as a molded member to improve body conformability. The absorbent core may have lines of reduced bending resistance resulting from material removal, for example in the form of holes or slits.

US 6,503,233 B1 discloses an absorbent article including a combination of downward bending lines and upwardly deviating shaping lines to achieve a better body conforming geometry. The fold lines are formed by embossing the absorbent material. The forming line is obtained through perforation or notches.

US 2015/0088084 A1 discloses a method for producing an absorbent structure with a three-dimensional configuration, including positioning at least a portion of the absorbent structure between opposing surfaces of a mold. At least one of the mold surfaces has a three-dimensional configuration. The three-dimensional configuration of the mold surface is transferred to the absorbent structure, so that the absorbent structure has a three-dimensional configuration corresponding to the three-dimensional configuration of the mold surface.

Application EP3342386A1 discloses an absorbent core including substantially continuous zones of one or more liquid intensive distribution structures and discrete zones of liquid absorption structures surrounding one or more liquid intensive distribution structures, wherein the one or more liquid intensive distribution structures are arranged to distribute liquid across the absorbent core at a rate greater than the rate of distribution of liquid throughout the absorbent core due to said continuous structures absorbing liquid, wherein said continuous zones are located along a direction that is substantially parallel to at least a portion of the perimeter of the core, wherein said portion of the perimeter of the core includes at least a portion of the sides of the core and one of the ends of the core.

Although the channels described in EP3342386A1 are preferred from a liquid handling perspective, there is still a need to further improve perceived dryness while maintaining absorption rates.

The technical objective of this invention is to provide a new absorbent article that utilizes a synergistic combination of a channel-containing core and a selective absorption distribution layer designed specifically to provide high absorption rates as well as exceptional low rewetting that provides the user with an even greater dry feeling from of this product.

Disclosure of the invention

In one aspect, the present disclosure relates to an absorbent article including an absorbent core disposed between a liquid-permeable topsheet and a liquid-impermeable backsheet, and a acquisition distribution layer disposed between said topsheet and said absorbent core, wherein the absorbent core comprises an absorbent material. a material selected from the group consisting of cellulose fibers, superabsorbent polymers, and combinations thereof, wherein said absorbent core comprises at least one interconnected channel not containing said absorbent material, said channel located along a longitudinal axis, and the absorbent core located along the specified longitudinal axis, and the length of the specified channel is from 10% to 95% of the length of the specified absorbent core, and the receiving distribution layer contains a layer of spunbond and/or carded nonwoven material including synthetic fibers, and the specified synthetic fibers are contained in an amount greater than 80 wt. .% relative to said receiving distribution layer, wherein the base weight of said receiving distribution layer is from 10 to 50 g/m ² .

Preferably, the length of said channel is from 30% to 90%, more preferably from 40% to 85%, most preferably from 50% to 80%, of the length of said absorbent core.

In one aspect, the invention relates to the use of a nonwoven material with a relative porosity of less than 9000 l/m ² /s as a receiving distribution layer for an absorbent article including an absorbent core located between a liquid-permeable top sheet and a liquid-impervious back sheet, wherein a receiving distribution layer is disposed between said topsheet and said absorbent core, wherein the absorbent core comprises an absorbent material selected from the group consisting of cellulose fibers, superabsorbent polymers, and combinations thereof, wherein said absorbent core comprises at least one interconnected channel, not containing the specified absorbent material, wherein the specified channel is located along the specified longitudinal axis, and the absorbent core is located along the specified longitudinal axis, and the length of the specified channel is from 10% to 95% of the length of the specified absorbent core.

In one aspect, the invention relates to an absorbent article comprising a front portion, a rear portion, a middle portion disposed between the front portion and a rear portion, a longitudinal axis extending along the length of said core and intersecting said front, middle, and rear portions, an absorbent core width which is perpendicular to said length, and the perimeter includes at least two opposite ends and at least two opposite sides located between said ends, wherein said core is a multi-layer core including at least first and second individual core layers located one on top another, wherein the first core layer contains a first concentration of superabsorbent polymer, and the second core layer contains a second concentration of superabsorbent polymer, wherein the first and/or second core layers include one or more channels, wherein the second core layer includes a first region of superabsorbent polymer particles on surface thereof which is opposite to said first core layer, wherein the first region is arranged in a pattern that substantially follows the shape of the channel(s), at least along a plane formed by the length and width of the core, such that the shape of said channel(s) essentially similar to the form of the indicated figure.

In one aspect, the disclosure relates to an absorbent core including a front portion, a rear portion, a middle portion located between the front portion and a rear portion, and a longitudinal axis extending along the length of said core and intersecting said front, middle, and rear portions, wherein the absorbent the core has a width perpendicular to said length and a perimeter including at least two opposite ends and at least two opposite sides located between said ends, wherein said core is a multi-layer core including at least two individual core layers, wherein wherein the first core layer contains a first concentration of superabsorbent polymer, and the second core layer contains a second concentration of superabsorbent polymer, wherein the first and second concentrations are different, wherein at least said first core layer includes one or more channels, wherein said channel(s) is continuous and interconnected in at least the length and width directions of said core such that at least two portions of the channels extending beyond said length are in fluid communication through a channel connecting portion located closer to said rear portion.

In one aspect, the invention relates to an absorbent core comprising a front portion, a rear portion, a middle portion located between the front portion and a rear portion, and a longitudinal axis extending along the length of said core and intersecting said front, middle, and rear portions, wherein the absorbent the core has a width perpendicular to said length and a perimeter including at least two opposite ends and at least two opposite sides located between said ends, wherein said core includes one or more channels having a first shape when the absorbent core is in dry state, and a second form when the absorbent core is in a wet state, and wherein said first and second forms are different.

In one aspect, the invention relates to an absorbent core including substantially continuous zones of one or more liquid intensive distribution structures and discrete zones of liquid absorption structures surrounding one or more liquid intensive distribution structures, wherein the one or more liquid intensive distribution structures are arranged such that to distribute liquid throughout the absorbent core at a rate greater than the rate of liquid distribution throughout the absorbent core by said discrete liquid absorbent structures, wherein said continuous zones are located substantially parallel to at least a portion of the perimeter of the core, wherein said portion of the perimeter of the core includes at least part sides of the core and one of the ends of the core.

In a further aspect, the invention relates to an absorbent core including: a front portion, a rear portion, an intermediate portion located between the front portion and a rear portion, and a longitudinal axis extending along the length of said core and intersecting said front, intermediate, and rear portions, with wherein the absorbent core has a width perpendicular to said length and a perimeter including at least two opposite ends and at least two opposite sides located between said ends, wherein said core includes one or more substantially interconnected channels extending at least through a portion of the intermediate zone along the length of the core and along at least a portion of said core width from one side of the core to the other, preferably said one or more interconnected channels being symmetrical or asymmetrical about the longitudinal axis.

In a preferred embodiment, the absorbent core comprises at least one of interconnected channels; preferably each of said channels forms a structure with a closed end in the form of a U-shape and preferably an open end in the form of two diverging ends or a funnel shape, preferably the closed end being located towards the rear of the absorbent core and the open end being located towards the front absorbent middle and further from said closed end.

In a further aspect, the invention relates to an absorbent article comprising said core, wherein said article is preferably selected from disposable diapers or panties, disposable incontinence diapers or absorbent panties, sanitary napkins or pads, wherein generally the channels in said core remain visible both before and after use of the product, preferably with the channels being more visible after use than before use of the product.

In yet another aspect, the invention relates to the use of an absorbent core according to the invention in an absorbent article for improved liquid distribution compared to a similar absorbent article including a core that does not contain substantially interconnected channels.

In yet another aspect, the invention relates to the use of an absorbent core according to the invention in an absorbent article providing three-stage liquid distribution, comprising a first liquid distribution at a first rate, a second liquid distribution at a second rate, and a third liquid distribution at a third rate, wherein said first rate is greater than or equal to is equal to said second speed, and said third speed is less than said first speed and less than or equal to said second speed, preferably wherein the driving force of the first liquid distribution is substantially interconnected channels, the driving force of the second liquid distribution is a three-dimensional absorbent material located in the core, and the driving force The third liquid distribution force is a certain amount of superabsorbent polymer dispersed in the three-dimensional absorbent material.

In yet another aspect, the invention relates to a method of producing an absorbent core, comprising the steps of: providing a mold containing a 3D insert, wherein said insert is shaped inversely to the shape of the desired channels, wherein substantially the entire surface of the mold is in fluid communication with a source reduced pressure, excluding the 3D insert, applying a first nonwoven fabric to said shape, applying a three-dimensional absorbent material to at least a portion of said nonwoven fabric, applying a second nonwoven fabric directly or indirectly to the three-dimensional absorbent material, optionally employing a bonding step to form a laminate consisting of said first nonwoven material, said second nonwoven material and said three-dimensional absorbent material disposed therebetween, optionally removing said laminate from the mold to form an absorbent core containing channels the opposite of the shape of said 3D insert, and in which at least During the step of applying the three-dimensional absorbent material, a source of reduced pressure is applied to provide a vacuum force acting on said three-dimensional absorbent material located around the 3D insert to substantially clear its surface of the three-dimensional absorbent material and form channels substantially without containing three-dimensional absorbent material.

Brief description of drawings

In fig. 1 is a schematic top view of an absorbent core according to one of the described embodiments;

in fig. 2 is a schematic top view of an absorbent core according to one of the described embodiments;

in fig. 3 is a schematic top view of an absorbent core according to one of the described embodiments;

in fig. 4 is a schematic top view of absorbent cores according to one of the described embodiments, having various geometric shapes formed by interconnected channels;

in fig. 5 is a general view of an absorbent article according to one of the described embodiments;

in fig. 6 shows a general view of the product according to one of the described embodiments;

in fig. 7 is a schematic top view of an absorbent article according to one of the described embodiments;

in fig. 8 is a schematic top view of an absorbent article according to one of the described embodiments;

in fig. 9 is a general view of an absorbent article according to one of the described embodiments;

in fig. 10 is a general view of a product according to one of the described embodiments;

FIG. 11 is a schematic top view of an absorbent article according to one of the described embodiments;

in fig. 12 is a schematic top view of an absorbent article according to one of the described embodiments;

in fig. 13 is a schematic view of an absorbent article according to one of the described embodiments;

in fig. 14 is a schematic view of an absorbent article according to one of the described embodiments;

in fig. 15A and FIG. 15B is a photograph of molds containing a 3D insert in accordance with one aspect of the present invention;

in fig. 16 shows interconnected channels, the width of which varies along the channels;

in fig. 15A and FIG. 15B is a photograph of molds containing a 3D insert in accordance with one aspect of the present invention;

in fig. 16 shows interconnected channels, the width of which varies along the channels;

in fig. 17A-D show embodiments of the present invention in which the absorbent core is connected to the acquisition and distribution layer;

in fig. 18A-B show the appearance of the channel in a dry state (FIG. 18A) and a wet state (FIG. 18B), respectively;

in fig. 19A-B show photographs of specimens and a test rig for performing suspension shear testing;

in fig. 20A is a cross-sectional view of a core according to one embodiment of the present invention, such as the embodiment shown in FIG. 1;

in fig. 20B is a cross-sectional view of an absorbent article in accordance with one embodiment of the present invention comprising the core shown in FIG. 20A;

in fig. 21A is a cross-sectional view of a core according to one embodiment of the present invention, such as the embodiment shown in FIG. 3;

in fig. 21B is a cross-sectional view of an absorbent article in accordance with one embodiment of the present invention comprising the core shown in FIG. 21A;

in fig. 22 illustrates an absorbent article according to one embodiment of the present invention comprising raised channels (ie, in a wet state);

fig. 23 is a photograph of two identical channel-containing diapers according to Example 9, the only difference being that the diaper indicated as "D" contains the ADL corresponding to pattern A/A', and the diaper indicated as "E" includes includes sample B/B'. The corresponding difference in residual moisture is presented visually.

Carrying out the invention

Unless otherwise indicated, all terms used in the disclosure of the characteristics of the present invention, including technical and scientific terms, have the meaning commonly understood by one skilled in the art to which this invention relates. By means of additional guidance, definitions of terms are included to provide a better understanding of the present invention.

The terms used in the description have the following meanings:

The indefinite articles “a”, “an”, and the definite article “the” used in the description refer to both the singular and plural entities being defined, unless the context clearly indicates otherwise. By way of example, "department" refers to one or more than one department.

As used herein, the term “about” refers to a measurable quantity such as a parameter, quantity, time duration, and so on; it is intended to include variations of +/-20% or less, preferably +/-10% or less, more preferably +/-5% or less, even more preferably +/-1% or less, and even more preferably +/-0.1% or less of the determined value; to the extent such deviations are suitable for implementation in the described disclosure. However, it must be understood that the meaning to which the modifier “about” refers is itself also specifically described.

As used in this disclosure, “comprise,” “containing,” and “comprises,” and “consists of,” are synonymous with “include,” “comprising,” “includes,” or “contains,” “containing,” “contains,” and are inclusive or non-limiting terms that define the presence of, for example, a component described below, and do not exclude or admit the presence of additional, not listed components, features, elements, members, steps, known in the art or described in the present invention.

The expression "weight %" (weight percent), here and throughout the specification, unless otherwise specified, refers to the relative weight of the respective component relative to the total weight of the composition.

The reduction of numerical intervals by limit values includes all numbers and fractions related to a given interval, as well as the given limit values.

"Absorbent article" refers to devices that absorb and retain liquid, and more specifically, refers to devices that are placed close to or in close proximity to the body of the user for the purpose of absorbing and retaining various exudates secreted by the body.

Absorbent articles include, but are not limited to, diapers, adult incontinence pants, potty training pants, diaper holders and pads, sanitary napkins, etc., as well as surgical dressings and sponges. The absorbent articles preferably include a longitudinal axis and a transverse axis perpendicular to said longitudinal axis. The longitudinal axis is usually selected in the direction from the front of the product to the rear in relation to the worn product, and the transverse axis is usually selected in the direction from the left side of the product to the right in relation to the worn product.

Disposable absorbent articles may include a liquid permeable topsheet, a backsheet coupled to the topsheet, and an absorbent core positioned and supported between the topsheet and the backsheet. The topsheet is effectively permeable to liquids to be retained or stored by the absorbent article, and the backsheet may or may not be substantially impermeable or otherwise effectively impervious to the intended liquids. The absorbent article may also include other components such as liquid wicking layers, liquid absorption layers, liquid distribution layers, transmission layers, barrier layers, wrap layers and the like, as well as combinations thereof. Disposable absorbent articles and components thereof may function to provide a body-facing surface and a clothing-facing surface.

An absorbent article such as a diaper includes a front waist region, a back waist region, an intermediate region connecting the front and back waist regions. As used herein, reference to a “front” region refers to the portion of an absorbent article that, in use, is typically positioned at the front of a subject, such as an infant or an adult. Reference to a “rear” region refers to a portion of an absorbent article that, in use, is typically positioned behind the subject, such as an infant or adult, and reference to an “intermediate” region refers to a portion that, in use, is typically positioned between the legs of a subject, such as an infant. or adult. The interstitial region is the region into which liquid is typically repeatedly ejected within the structure of the absorbent article.

The above-mentioned "front", "back or bottom" and "intermediate" portions of the absorbent core generally refer to areas of the absorbent core in close proximity to corresponding areas of the absorbent article. For example, the "front" core portion is the portion closest to the front of the subject's body while being worn, the "back or bottom" core portion is the portion closest to the rear or lower portion of the subject's body while being worn, and " The "intermediate" region is the middle portion of the absorbent core located between the "front" and "back or bottom" portions.

Preferably, the diaper includes a liquid-permeable "top sheet", a liquid-impervious "bottom sheet", and an "absorbent medium" located between the top sheet and the bottom sheet. The topsheet, backsheet, and absorbent medium can be made from any material known to one skilled in the art.

The top sheet is typically located on or near the body-facing surface of the article, while the bottom sheet is typically located on or near the garment-facing surface of the article. The article may optionally include one or more separate layers in addition to the backsheet that are located between the backsheet and the absorbent medium. The top sheet and the bottom sheet are fastened or otherwise connected together in a functional manner.

An "absorbent medium" or "absorbent core" is an absorbent structure located between the topsheet and the backsheet of an absorbent article, at least in the intermediate region of the absorbent article, and is capable of absorbing and retaining liquid body exudates. The size and absorbent capacity of the absorbent medium must be compatible with the size of the intended wearer and the volume of fluid encountered during the intended use of the absorbent article. Additionally, the size and absorbency can be customized to suit users from infants to adults. The absorbent media can be manufactured in a wide variety of shapes (eg, rectangular, trapezoidal, T-shaped, I-shaped, hourglass, etc.) and a wide variety of materials. Examples of commonly encountered absorbent materials are cellulose wadding, fabric layers, highly absorbent polymers (so-called superabsorbent polymer particles (SAP)), absorbent foams, absorbent nonwovens, or the like. Typically, the absorbent material combines cellulose wadding with superabsorbent polymers.

The "acquisition and distribution layer", "ADL" or "discharge control portion" refers to a sublayer, which is preferably a non-woven discharge layer, located under the top sheet of the absorbent product, which accelerates the transfer and improves the distribution of liquids across the absorbent core. Typically, the ejection control portion is less hydrophilic than the retention portion and is capable of quickly collecting and holding liquid ejections for a period of time and transferring that liquid from the point of release to other parts of the absorbent structure, particularly the retention portion. This configuration helps prevent leakage and accumulation of liquid in the portion of the absorbent garment facing the user's skin, thereby reducing the user's feeling of wetness. Preferably, the ejection control part is located between the top sheet and the holding part.

As used herein, the term "bulk density" refers to the mass of a material per unit volume. Bulk density is usually expressed in mass/volume units (for example, grams per cubic centimeter). The bulk density of flat, typically two-dimensional materials, such as fibrous nonwoven webs, can be calculated from thickness measurements and basis weight of the sample. The sample thickness is determined using a Model 49-70 thickness gauge from TMI (Testing Machines Incorporated) of Amityville, New York (alternatively, a J 100/A portable thickness gauge can be used). Thickness is measured using a 6.45 cm (2 in.) diameter circular support under an applied pressure of about 1.38 x 10 ³ Pa (about 0.2 pounds per square inch (psi)). The base weight of the sample is determined primarily in accordance with ASTM D-3776-9 with the following modifications: 1) the sample is trimmed to a 4" x 4" (10.16 cm x 10.16 cm) square and 2) a total of 9 samples are weighed.

As used herein, the term "specific volume" refers to the reciprocal bulk density of a material, measured as volume per unit mass, and can be expressed in cubic centimeters per gram.

As used herein, the term "average pore size" refers to a measurement of the average pore diameter determined by the fluid displacement method using a Coulter Porometer and Coulter POROFIL® test fluid from Coulter Electronics Limited, Luton, England. The average pore size is determined by wetting the test sample with a very low surface tension liquid (ie Coulter POROFIL®). Air pressure is applied to one side of the sample. After some time, as air pressure increases, the capillary attraction of the liquid in the largest pores is overcome, pushing the liquid out and allowing air to pass through the sample. With a further increase in air pressure, smaller and smaller pores will be released. The flow rate versus pressure can be derived for a wet sample and compared with the results for a dry sample. The average pore size is measured at the point at which the curve representing the 50% flow rate for a dry sample as a function of pressure intersects the curve representing the flow rate for a wet sample as a function of pressure. The diameter of a pore that opens at a given pressure (i.e., the average pore size) can be determined using the following equation:

Pore diameter (µm) = (40τ)/pressure

where τ = surface tension of the liquid, expressed in mN/m; pressure is the applied pressure expressed in millibars (mbar), and the extremely low surface tension of the liquid used to wet the sample leads to the conclusion that the contact angle formed by the liquid on the sample is approximately zero.

As used herein, the term "adhesive" is intended to mean any suitable hot-melt, water-based, or solvent-based adhesive that can be applied to the surface of the film layer in a desired pattern or grid of adhesive regions to form the film-nonwoven laminate of the present invention. Accordingly, suitable adhesives include conventional hot melt adhesives, contact adhesives, and curing adhesives (ie, polyurethane).

As used herein, the term “adhesive bonding” means a bonding process that results in bonding through the use of an adhesive. Application of the adhesive can be accomplished in a variety of ways, such as crevice application, spray application, and other topical application methods. In addition, such an adhesive can be applied to the inside of a product component and then pressure applied to it so that when the second product component comes into contact with the product to which the adhesive is applied, an adhesive bond is formed between the two components.

As used herein, the term “air-spun web” refers to a material comprising cellulosic fibers, such as cellulose wadding fibers, separated, for example, by a hammer mill, and then applied to a porous surface in the absence of a significant amount of binder fibers. For example, a typical example of an air-molded material is Airfelt, used as the absorbent core in many types of diapers.

As used herein, the term “dry air-spun web” is a fibrous structure produced primarily by a process involving the application of air-entrained fibers to a substrate, typically in the presence of binder fibers, and typically followed by densification and thermal bonding. In addition to traditional "thermally bonded air-spun structures" (structures formed in the presence of a non-tacky binder material and subsequently thermally bonded), the term "dry air-spun" as used herein may also include a coform obtained by combining air-entrained dry dispersed cellulose fibers. with still tacky synthetic meltblown polymer fibers. In addition, the air-spun web to which a binder material is subsequently added may be considered within the meaning of the term "dry-air-spun" according to the present disclosure. The binder may be added to the air-spun web in liquid form (i.e. in the form of an aqueous solution or melt) using spray guns, directional injection or impregnation, vacuum application, foam impregnation, etc. Solid binder particles can also be added by mechanical or pneumatic methods.

As used herein, the term “hot air bonded nonwoven” is a nonwoven structure formed primarily by a process that involves treating the surface of the nonwoven with heated air. During the air bonding process, heated air passes through holes in a chamber above the nonwoven material. Unlike hot ovens, which force air through the material, the hot air bonding process uses negative suction pressure to force air through an open conveyor apron that holds the nonwoven fabric as it moves through the oven. Blowing air through the material allows for rapid and uniform heat transfer to minimize distortion of the nonwoven fabric. The bonding agents used in the hot air bonding process include crystalline bonding fibers and powders that, when melted, form molten droplets across the entire cross-section of the nonwoven fabric. As the material cools, bonding occurs at the points where these droplets are located.

As used herein, the term "bonded" includes configurations in which the top sheet is directly connected to the bottom sheet by attaching the top sheet directly to the bottom sheet, and configurations in which the top sheet is connected to the bottom sheet by attaching the top sheet to intermediate components , which in turn are attached to the bottom sheet. The top sheet and the bottom sheet may be attached to each other by joining methods such as adhesive bonding, ultrasonic welding, thermal bonding, or any other bonding methods known in the art. For example, a uniform continuous layer of adhesive, a layer of adhesive applied in a pattern, adhesive sprayed in a pattern, or a series of discrete lines, swirls, or dots of construction adhesive may be used to attach the top sheet to the bottom sheet. It should be understood that the connection methods described above can also be used to interconnect and assemble other various components of the described product.

The terms "back region" and "posterior back region" are used interchangeably herein and refer to the area of an absorbent article in contact with the user's back while the absorbent article is being worn.

The term "backsheet" refers to the material forming the outer cover of the absorbent article. The backsheet prevents exudates contained in the absorbent structure from wetting items such as sheets and outerwear in contact with the disposable absorbent article. The backsheet may be a single layer of material or may be a composite layer consisting of multiple components arranged in a row or laminated. The backsheet may be the same or different in different parts of the absorbent article. At least in the region of the absorbent medium, the backsheet includes a liquid impervious material in the form of a thin polymer film, such as a polyethylene or polypropylene film, a nonwoven material coated with a liquid impermeable material, a hydrophobic nonwoven material resistant to liquid penetration, or a polymer film laminate and nonwoven material. The backsheet material may be breathable to allow water vapor to escape from the absorbent material while preventing liquids from penetrating through it. Examples of breathable backsheet materials include porous polymer films, nonwoven laminates composed of spunbond and meltblown layers, and laminates composed of porous polymer films and nonwovens.

As used herein, the terms "abdominal region" or "anterior abdominal region" are synonymous and refer to the area of the absorbent article that comes into contact with the user's abdomen while the article is being worn.

The term "blend" means a mixture of two or more polymers, while the term "alloy" means a subclass of mixtures in which the components are immiscible but have been compatibilized.

As used herein, the terms "skin-facing", "body-facing" or "body-side" surface mean the surface of a product or component intended to be close to or in contact with the wearer's body during normal use, while "external", "body-facing" out" or "garment facing" surface is on the opposite side and is intended to face away from the wearer's body during normal use. Such outer surface may be positioned to face or contact the wearer's underwear while the absorbent article is being worn.

"Bound" refers to joining, gluing, tying, attaching, etc. at least two elements. Two elements will be considered to be connected when they are connected directly to each other or indirectly to each other, for example, if each of them is directly connected to intermediate elements.

The term "breathable" refers to films that have a water vapor transmission rate (WVTR) of at least 300 grams/m² over 24 hours.

“Card web (or ply(s) or nonwoven web)” refers to webs made from staple fibers that are passed through a stripper or plucker that opens and aligns the staple fibers in the machine direction to produce an overall machine-oriented fibrous nonwoven web. The web is then secured by one or more of several known bonding methods. Bonding of nonwoven fabrics can be accomplished in a number of ways: powder bonding, in which a powdered adhesive is spread over the web and then activated, usually by heating the web and adhesive with hot air; canvas bonding, in which hot calender rolls or bonding equipment are used to bond the fibers ultrasonic welding, usually in a localized bonding pattern, although the web can be bonded over its entire surface if desired, air bonding, which involves passing air hot enough through the web to soften at least one of the components of the web, chemical bonding with using, for example, latex adhesives that are applied to the web, for example by spraying, and compaction by mechanical methods such as stitching and hydraulic coupling. Thus, carded thermally bonded nonwoven fabric refers to carded nonwoven fabric that is thermally bonded.

As used herein, the term “cellulosic” is intended to include any material containing cellulose as a major component, and specifically containing at least 50 weight percent cellulose or a cellulose derivative. Thus, the term includes cotton, regular wood fibers, non-wood cellulose fibers, cellulose acetate, cellulose triacetate, chemical cellulose fiber, thermomechanically treated wood pulp, chemically treated wood pulp, debonded wood pulp, plant silk or bacterial cellulose.

"Body" refers to the underlying component of an absorbent article onto which the remaining structure of the article is gradually applied or superimposed, for example, in the case of a diaper, the structural elements that give the diaper the shape of a short pants or pant when configured to be worn, such as a backsheet, a topsheet , or a combination of top sheet and bottom sheet.

The term “coform” as used herein is intended to describe a blend of meltblown fibers and cellulosic fibers produced by air-spinning a meltblown polymeric material while simultaneously blowing air-suspended cellulose fibers into a stream of meltblown fibers. The coform material may also include other materials such as superabsorbent particles. Meltblown fibers containing wood fibers are collected on a forming surface, such as a perforated conveyor belt. The forming surface may include a gas-permeable material, such as a spunbond fabric material, placed on the forming surface.

“Expression” refers to the process or result of pressing when force is applied to an object, resulting in an increase in the density of the object.

The term “comprising predominantly” does not exclude the presence of additional materials that do not significantly affect the desired characteristics of the composition or product. Examples of such materials include, but are not limited to, pigments, antioxidants, stabilizers, surfactants, waxes, flow activators, solvents, microparticles and substances added to improve the processability of the composition.

The diaper may include "retain flaps" or "protective bumpers". It is believed that retention valves are particularly suitable for containing fecal matter and preventing the lateral flow of liquid discharges until such liquid discharges are absorbed by the absorbent article. There are many types of retention valve designs known. Such retention flaps typically include a leading edge intended to be attached to the absorbent article and an opposing distal edge which is not typically attached to the absorbent article along at least a portion of its length. An elastic component is typically located adjacent the distal edge to hold the retention flap in an upright position and maintain a seal between the distal edge of the retention flap and the user's body during wear. The elastic component is typically located between two layers of material such that the elastic does not come into contact with the user's body. Retaining valves can be made from a variety of materials, such as polypropylene, polyester, cellulosic fiber, nylon, foams, polymer films, molded films and resilient foams. Retaining valves can be made in a number of ways. For example, retaining flaps can be woven, non-woven, spunbond, carded, molded, blown, etc.

The diaper may include sealing pads around the legs. "Seal pads" around the legs help prevent body exudates from leaking when the user applies compressive force to the absorbent article. In particular, the rigidity of the leg seals prevents the leg openings of the absorbent article from twisting and bunching, which can lead to leaks. In addition, the elasticity and fit of the leg seals ensures that the body facing surface of the leg seals will provide a proper seal against the user's body. The physical properties of leg liners, such as density and stiffness, also contribute to the formation of a gap between the body-facing liner, the outer surface and absorbent core, and the wearer's body during wear. Accordingly, a free volume is created between the user's body and the body-facing pad and absorbent core to help retain body exudates.

The "continuous belt" may be an elastomeric, fabric-like, non-woven fibrous material, such as an elastomeric stretch bonded laminated web or an elastomeric meltblown web. By appropriate selection of materials, the continuous belt can be given temporary inelasticity, for example as in compression. If elasticity is temporarily inhibited, the elastic material of which the belt is composed can be activated, for example by heat treatment, to restore elasticity.

"Conventional thermoplastic adhesive" means a composition typically containing several components. These components typically include one or more polymers to provide cohesive strength (e.g., aliphatic polyolefins such as poly(ethylene-co-propylene) copolymer, ethylene-vinyl acetate copolymers, styrene-butadiene or styrene-isoprene block copolymers, etc.), a resin or similar substance (sometimes called a tackifying agent) to provide cohesive strength (e.g., hydrocarbons distilled from petroleum distillates, rosins and/or rosin esters, terpenes derived from, for example, wood or citrus fruits, etc.) optionally waxes, plasticizers and other viscosity (i.e. flow) modifiers (examples of such materials include, but are not limited to, mineral oil, polybutene, paraffinic oils, ester synthetic oils, etc.) and/or other additives, including, but not limited to, antioxidants or other stabilizers. A typical thermoplastic adhesive formulation may contain from about 15 to about 35 weight percent polymer or polymers to impart cohesive strength, from about 50 to about 65 weight percent resin or other tackifying agent or tackifying agents, from more than zero to about 30 weight percent plasticizer or other viscosity modifier, and optionally less than 1 weight percent stabilizer or other additive. It should be understood that other adhesive compositions containing other weight percentages of these components are possible.

The term "density" or "concentration" when applied to an absorbent material, particularly a SAP layer, refers to the amount of absorbent material divided by the surface area of the layer covered by the absorbent material.

As used herein, the term "diaper" refers to an absorbent article typically worn by infants on the lower part of the body.

The term "disposable" is used here to describe absorbent articles that are generally not intended to be washed or otherwise recovered or reused as an absorbent article (that is, they are intended to be discarded after a single use and, preferably, to be recycled for reuse, compost or otherwise dispose of in an environmentally acceptable manner).

As used herein, the term "elastic resistance" describes an elastic force that resists an applied tensile force, causing the material possessing it to contract before regaining a free configuration in response to the tensile force.

The terms “elastic”, “elastomer”, “elasticity” and their derivatives used in the description describe the ability of various materials and objects possessing it to undergo reversible deformation under the influence of tension, for example, in a compressed or stretched state, in at least one direction, when a force is applied to a given material, and return almost to its original dimensions at rest, that is, in the absence of a given force, without rupture or damage. Preferably, it refers to a material or composite that is capable of elongating in at least one direction by at least 50% of its free length, and which will return, in the absence of applied tension, at least 40% of its elongation. Accordingly, in the absence of applied tension at 50% elongation, the material or composite shortens to a free length of no more than 130% of its original length. Examples of suitable elastomeric materials include polyester-polyamide block copolymers, polyurethanes, A-B-A and A-B synthetic linear block copolymers, chlorinated rubber/EVA blends, EPDM rubbers, EPM rubbers, blends EPDM/EPM/EVA, etc.

The term “elasticated” refers to a material, layer or substrate that is not inherently elastic but has been rendered elastic, for example by bonding an elastic material, layer or substrate thereto.

"Elongation" means the ratio of the stretch of a material to the length of that material before elongation (expressed as a percentage), represented as follows: "Draw" means the change in length of a material due to stretching (expressed in units of length).

As used herein, the term "extensible" means elongable in at least one direction, but not necessarily recoverable.

The term "fabric" is used in the description to describe all types of woven, knitted and non-woven fiber fabrics.

"Retention means" such as Velcro fasteners are typically applied to the back waist region of the diaper to provide a mechanism for holding the diaper on the wearer. Restraints such as Velcro fasteners, clasps, pins, straps, hooks, buckles, Velcro fasteners (e.g., VELCRO® type fasteners), etc. can be used and are typically applied to the sides of the rear waist region. diaper to provide a mechanism for holding the diaper around the user's waist in a comfortable manner. Velcro fasteners can be any type of fastener known in the art and are typically used at the edges of the diaper. For example, adhesive retainers, mechanical retainers, Velcro retainers, fasteners, pins, or buckles may be used alone or in combination. For example, the retainers may be adhesive retainers designed to be releasably adhered to a portion of the attachment zone attached to the front waist portion of the diaper to provide a re-attachable adhesive retention system.

The term "finished" or "finished" when used in relation to a product means that the product has been produced in a suitable manner for the relevant purpose.

The term "flexible" refers to materials that bend easily and can easily conform to the overall shape and contours of the user's body.

As used herein, the term "protective clothing" means any type of clothing that can be worn. It includes diapers, potty training panties, incontinence products, surgical gowns, industrial overalls, underwear, briefs, shirts, jackets, etc.

Many known superabsorbent polymer particles exhibit gel blocking properties. “Gel blocking” occurs when superabsorbent polymer particles become wet and the particles swell enough to prevent liquid from moving to other areas of the absorbent structure. Therefore, wetting of other areas of the absorbent component occurs as a result of a very slow diffusion process. In practical terms, this means that the absorption of liquids by the absorbent structure is much slower than the rate at which they are released, especially in high flow situations. Leaks from an absorbent article can occur long before the SAP particles in the absorbent component are close to full saturation or before the liquid is able to diffuse or be absorbed past the “blocking” particles into the rest of the absorbent component. Gel blocking can be a particularly serious problem if the superabsorbent polymer particles do not have adequate gel strength and become deformed or disintegrate under stress as the particles swell with the absorbed liquid.

The term "graphic" includes, but is not limited to, any type of design, image, sign, figure, code, word, pattern, etc. For a product such as potty training panties, the graphic design will typically include objects associated with little boys and little girls, such as colorful trucks, airplanes, balls, dolls, bows, or the like.

"Hydraulic bonding process" refers to the production of non-woven fabrics. This method involves directing a series of water jets onto a fibrous web placed on a moving conveyor belt. Jets of water are passed downward through a mass of fibers and upon contact with the surface of the tape, the jets rebound and break. The released energy causes the mass of fibers to intertwine.

The term “highly absorbent substance” refers to substances that are capable of absorbing at least 10 times their own weight in liquid. The highly absorbent material may include gelling agents such as superabsorbent polymers. Superabsorbent polymers are water-swelling, water-insoluble organic or inorganic substances capable of absorbing an aqueous solution containing 0.9 weight percent sodium chloride in an amount at least 20 times their own weight. Absorbent gelling agents can be natural, synthetic and modified natural polymers and substances. In addition, the absorbent gelling agents may be inorganic substances such as silica gels or organic compounds such as cross-linked polymers. The term "cross-linked" refers to any method of effectively converting normally water-soluble substances into substances that are substantially insoluble but water-swellable. Such methods may include, for example, entanglement by physical means, crystalline domains, covalent bonds, ionic complexes and associations, hydrophilic associations such as hydrogen bonds, and hydrophobic associations such as van der Waals bonds. Examples of synthetic absorbent gelling polymers include alkali metal and ammonium salts with poly(acrylic acid) and poly(methacrylic acid), poly(acrylamides), poly(vinyl ethers), copolymers of maleic anhydride with vinyl ethers and alpha-olefins, poly( vinylpyrrolidone), poly(vinylmorpholinone), poly(vinyl alcohol), as well as mixtures and copolymers based on them. Other polymers suitable for use in the absorbent structure include natural and modified natural polymers such as hydrolyzed acrylonitrile-grafted starch, acrylic acid-grafted starch, methylcellulose, carboxymethylcellulose, hydroxypropylcellulose and natural gums such as alginates, xanthan gum, bean gum wood, etc. It is also possible to use mixtures of natural and wholly or partly synthetic absorbent polymers. Synthetic absorbent gelling agents are typically xerogels that form hydrogels when wet. However, the term "hydrogel" has generally been used to describe both wetted and non-wetted forms of the substance. A substance with high absorption capacity can have many geometric shapes. In general, it is preferable that the highly absorbent material be in the form of discrete particles. However, the highly absorbent material may be in the form of fibers, flakes, rods, spheres, needles, spirals or semi-spirals, cubic, rod-like, polyhedral or the like. It is also possible to use conglomerates of particles of a substance having a high absorption capacity. The highly absorbent material may be present in the absorbent core in an amount of from about 5 to about 100 weight percent, and desirably from about 30 to about 100 weight percent, based on the total weight of the absorption core. The distribution of the highly absorbent material in different parts of the absorbent core may vary depending on the intended end use of the absorbent core. The highly absorbent material can be arranged as a generally discrete layer in a matrix of hydrophilic fibers. Alternatively, the absorbent core may include a laminate of the fibrous web and the highly absorbent material, or other suitable methods of localized retention of the highly absorbent material in a localized area may be used.

"Velcro" refers to complementary retention means comprising a "hook" portion and a "loop" portion and allows for reattachment. As used herein, the term "hook" refers to any element that is capable of interlocking with another element, the so-called "loop" part. The term "hook" is not limited to "hooks" in their usual sense, but covers all forms of interlocking elements that engage in either one or two directions. Likewise, the term "loop" is not limited to "loops" in their usual sense, but also includes any structure capable of interlocking with a "hook" retainer. Examples of “loop” materials are fibrous structures such as nonwovens.

The term "hydrophilic" describes the fibers, or the surface of the fibers, wetted by aqueous liquids in contact with the fibers. The degree of wetting of materials can in turn be described in terms of the contact angles and surface tension of the liquids and materials involved. The term "wettable" is intended to refer to a fiber whose contact angle when wetted by a liquid such as water, synthetic urine, or a 0.9 weight percent aqueous salt solution in air is less than 90°, whereas the terms "hydrophobic" or “non-wettable” describes fibers whose contact angles are greater than or equal to 90°.

As used herein, the term “impervious” generally refers to articles and/or components that are substantially incapable of passing through water-containing liquid at a pressure of 1.0 kPa or less. Preferably, the impermeable article or element does not allow water-containing liquid to pass through it at a pressure of 3.4 kPa or less. More preferably, the impermeable article or element does not allow water-containing liquid to pass through it at a pressure of 6.8 kPa or less. A product or element that is not impermeable is permeable.

The term "composite" is used to refer to different parts of one single element, rather than separate structures attached or placed together, or placed next to each other.

The terms "connect", "connection", "connected" or variations thereof, when used to describe the relationship between two or more elements, mean that the elements can be connected to each other in any suitable manner, for example, heat welding, ultrasonic welding, bonding , firmware or the like. In addition, the elements may be connected directly to each other, or between them there may be one or more elements that are all connected to each other.

The term "plane-parallel state" is intended to refer to an article when it is flattened to a flat state or flattened to a substantially flat state and used, as opposed to when the article is otherwise formed, for example, when the article is folded or shaped during use or for its use by the user.

"Laminate" refers to elements attached to each other to form a layered structure.

The term "layer" can refer to, but is not limited to, any type of substrate such as woven fabric, non-woven fabric, films, laminates, composites, elastomeric materials or the like. The layer may be liquid and air permeable, air permeable but liquid impermeable, both air and liquid impermeable, or the like. When used in the singular, it can have a dual meaning - for one element or for many elements.

The intermediate region of the absorbent article preferably includes opposing longitudinal side portions comprising two elasticized, longitudinally extendable leg cuffs. Leg cuffs are typically designed to conform to the wearer's legs while worn and serve as a mechanical barrier to lateral leakage of body exudates. The leg cuffs are elasticized with leg elastics. The diaper may also include a front waistband and a back waistband. Materials suitable for use as leg elastics are known to those skilled in the art. Examples of such materials include threads or tapes of polymeric elastomeric material adhered to the cuff of the diaper when in a stretched state, or attached to the diaper when the diaper is folded so that elastic compressive forces are imparted to the cuff. Examples of appropriate for the use of elastomeric materials include polyester-polyamide blocksopolymers, polyurethanes, synthetic linear blockopolymers of the A-B-A and A-B type mixture/EVA (ethylene-vinyl acetate), EPPPM-based rubbers, EPM-based rubber (ethylene). propylene monomer) , EPDM/EPM/EVA mixtures, etc.

"Liquid" means a substance and/or material, other than a gas, that is fluid and capable of taking on the internal shape of the container into which it is poured or placed.

“Longitudinal” is the direction parallel to the maximum linear dimension of the product.

The term "meltblown fibers" means fibers produced by extruding flattened thermoplastic material through the thin, usually round capillaries of an extruder die, as molten strands or filaments into a high-velocity gas stream (such as air), which thins the filament strands of the molten thermoplastic material, reducing them diameter, which can approach the diameter of microfiber. Typically, the average meltblown fiber diameter is up to approximately 10 microns. After fiber formation, the meltblown fibers are carried away by a high-velocity gas flow and deposited on a receiving surface to form a web of randomly scattered meltblown fibers.

The term "inelastic" refers to any material that does not fall within the definition of "elastic" above.

The term "non-woven fabric or web" means a sheet material whose structure consists of individual fibers or threads that are intertwined, but not in a regular manner, such as in the case of knitting or weaving processes. Nonwoven fabrics or webs have been produced by a variety of methods, such as melt blown methods, spin bonding methods, and bonded carded web methods.

“Underpants” refers to clothing that has a hole for a waistband and two holes for the legs, similar to shorts, swim trunks, or the like. The garments described may or may not have a hand-tearable side seam.

The terms “particle”, “particles”, “microparticle”, “microparticles” and so on mean that the substance as a whole is in the form of discrete units. These units may include granules, powders, spheres, fines, or the like, as well as combinations thereof. The particles may have any desired shape, such as cubic, rod-like, polyhedral, spherical or hemispherical, rounded or semi-rounded, angular, irregular, etc. Shapes with the largest maximum size/minimum size ratio, such as needles, flakes and fibers, are also considered for inclusion herein. The terms "particle" or "microparticle" may also include agglomerates containing more than one individual particle, microparticle or the like. In addition, a particle, microparticle, or any desired agglomerate thereof may include more than one type of material.

The term "polymer" generally includes, but is not limited to, homopolymers, copolymers, such as block, graft, random and alternating copolymers, terpolymers, etc., as well as mixtures and modifications thereof. In addition, unless otherwise specifically limited, the term "polymer" includes all possible geometric configurations of a given substance. These configurations include, but are not limited to, isotactic, syndiotactic, and statistical symmetry types.

By "packaged" as used herein, it is meant that one or more absorbent articles are packaged as a single unit prior to storage.

"Cellulose wadding" or "fluff pulp" refers to a material made from cellulose fibers. These fibers can be either natural or synthetic, or a combination of both. This material is usually lightweight and has absorbent properties.

The term "reattachable" refers to the property of two elements being capable of being releasably bonded, separated, and then reattached without significant permanent deformation or rupture.

The "holding portion" or "liquid absorbent layer" represents a portion of the absorbent medium. This portion may include a matrix of hydrophilic fibers, such as a fluff pulp web, mixed with particles of a highly absorbent material. In particular structures, the retention portion may include a mixture of superabsorbent hydrogel particles and synthetic meltblown polymer fibers, or a mixture of superabsorbent particles with a fibrous coform material comprising a mixture of natural fibers and/or synthetic polymer fibers. The superabsorbent particles may be a substantially homogeneous mixture with hydrophilic fibers, or a heterogeneous mixture. For example, the concentration of superabsorbent particles may vary unevenly over a large portion of the absorbent structure, with lower concentrations toward the body side of the absorbent structure and relatively higher concentrations toward the outer side of the absorbent structure. The superabsorbent particles may also be arranged as a typically discrete layer within a matrix of hydrophilic fibers. In addition, two or more different types of absorbent may be selectively located at different locations within or along a given fiber matrix.

As used herein, the term “sheet” or “sheet material” refers to woven materials, non-woven fabrics, polymer films, polymer web-like materials and polymer foam sheets.

The absorbent article may also include side panels. The "side panels" may be of any shape, such as, but not limited to, square, rectangular, triangular, circular, and trapezoidal. They can be connected to the respective opposing parts of the rear region by known methods such as heat welding or gluing. The side panels may also be formed integrally with the rear portion by extending outwardly and bonding a respective top layer and/or bottom layer and/or absorbent medium into projections shaped like the side panels. Preferably, the side panels are produced by forming a laminate of a nonwoven material layer, a thermoplastic film layer and an elastic material layer. A layer of elastic material can be sandwiched between a layer of nonwoven material and a thermoplastic film using adhesive layers. The nonwoven layer may consist of natural fibers, synthetic fibers, or a mixture of natural fibers and synthetic fibers. The thermoplastic film layer can be made of polyethylene or polypropylene.

The term "spunbond fibers (or nonwoven layer(s)" refers to fibers produced by extruding molten thermoplastic polymers into filaments or filaments from a plurality of relatively thin, usually round, spinneret capillaries and then rapidly drawing and folding the extruded filaments using pull-out or other known pulling mechanisms to impart molecular orientation and physical strength to the threads. The average diameter of spunbond fibers is usually 15-60 microns or more. The die can be either a large die containing several thousand holes per meter of width or a series of small dies, for example containing only 40 holes.

As used herein, the term spunbond meltblown spunbond (SMS) nonwoven fabric refers to a multi-layer composite layer comprising a web of meltblown fibers sandwiched between and bonded to two layers of spunbond. The SMS nonwoven fabric can be produced inline by sequentially applying a first layer of spunbond fibers, a layer of meltblown fibers, and a second layer of spunbond fibers onto a moving porous receiving surface. The assembled layers can be held together by passing them through a clamping device formed by two rollers, which can be heated or unheated, and smooth or patterned. Alternatively, the individual spunbond and meltblown layers can be pre-fabricated, optionally bonded, and arranged individually, for example by winding the fabrics onto winding rollers. The individual layers can be layered later and bonded together to form an SMS nonwoven fabric. Additional layers of spunbond or meltblown can be included in the SMS fabric, for example, spunbond-meltblown-meltblown-spunbond (SMMS), etc.

"Staple fibers" refer to commercially available fibers with a diameter of from less than about 0.001 mm to about more than 0.2 mm; they are manufactured in several different forms, such as short fibers with a length of about 10 to 50 mm, and long fibers with a length in excess of 50 mm, preferably up to 100 mm.

By "tensile" is meant that a material is capable of expanding beyond its original size in at least one dimension when subjected to a tensile force (ie stretch) applied in one direction of that dimension without rupture of the material. A stretch of, for example, 50% means that a material having an original length of 100 mm has reached a length of 150 mm. The stretch can be unidirectional, bidirectional or multidirectional. The specific tensile properties of a material can vary along any of the tensile vectors. The term may include elastic materials as well as non-woven materials, which may be stretchable in nature, but not necessarily in an elastic manner. Such nonwoven materials can be made to behave in an elastic manner by bonding them to elastic films.

By "channels" it is meant that the structure (eg, the absorbent core) includes recessed areas defining visible channels or passages that typically extend along the longitudinal axis of the core and have a depth in a direction perpendicular to the longitudinal axis. The term "visible" in the present description means that which is clearly visible to the naked eye, and typically that the channels are generally greater than 1 mm wide, preferably from 5 mm to 50 mm, more preferably from 8 mm to 40 mm , more preferably from 10 mm to 30 mm, even more preferably from 10 mm to less than 25 mm.

By “interconnected” is meant that said structure (eg, channels) forms a substantially continuous path, for example, from a first end of a channel to a second end of the same channel.

By “substantially” is meant at least a major part of said structure. For example, in relation to interconnected channels, "substantially interconnected" means that the majority of the channels are interconnected and can generally be traced along a straight and continuous path from one end of the channel to the other end of the channel, with said ends (also referred to herein as end positions) may be spaced apart in the transverse direction of the core and located closer to part of the perimeter of the core, preferably its sides.

By “directly on” is meant that said property extends to said structure such that the two components are in direct contact with each other for at least a significant portion of said structure.

By "not directly on" is meant that said property extends to said structure, but in such a way that the two components are not in direct contact with each other for at least a significant portion of said structure. For example, a nonwoven fabric not directly applied to a three-dimensional absorbent material includes an additional layer of material between said nonwoven fabric and said three-dimensional absorbent material.

Use of the term "substrate" includes, but is not limited to, woven or non-woven fabrics, porous films, ink-permeable films, papers, composite structures or the like.

Superabsorbent materials suitable for use in the present disclosure are known to those skilled in the art, and can be in any usable form, such as particles, fibers, and mixtures thereof. Generally speaking, the "superabsorbent material" may be a water-swellable, typically water-insoluble, hydrogel-forming polymeric absorbent material capable of absorbing at least about 15, suitably about 30, and possibly about 60 times or more of its own weight in physiological saline solution (eg, saline solution containing 0.9 wt.% NaCl). The superabsorbent material may be biodegradable or bipolar. The hydrogelling polymer absorbent material can be prepared from an organic hydrogelling polymeric material, which may include natural substances such as agar-agar, pectin and guar gum, modified natural substances such as carboxymethylcellulose, carboxyethylcellulose and hydroxypropylcellulose, and synthetic hydrogelling polymers. Synthetic hydrogel-forming polymers include, for example, alkali metal salts of polyacrylic acid, polyacrylamides, polyvinyl alcohol, ethylene-maleic anhydride copolymers, polyvinyl ethers, polyvinylmorpholinone, vinyl sulfonic acid polymers and copolymers, polyacrylates, polyacrylamides, polyvinylpyridine, etc. Other suitable hydrogel-forming polymers include hydrolyzed acrylonitrile-grafted starch, acrylic acid-grafted starch, and isobutylene-maleic anhydride copolymers, and mixtures thereof. Hydrogel-forming polymers can be slightly cross-linked to render the material substantially insoluble in water. Crosslinking can be accomplished, for example, by radiation, or by the formation of covalent, ionic, van der Waals, or hydrogen bonds. The superabsorbent material may suitably be included in a particular storage or retention portion of the absorbent system and may optionally be used in other components or portions of the absorbent article. The superabsorbent material may be included in the absorbent layer of the absorbent article according to the present invention in an amount of up to about 60% by weight. Typically, superabsorbent material, if present, is included in an amount of from about 5% to about 40% by weight, based on the total weight of the absorbent layer.

"Superabsorbent polymer particles" or "SAP" refers to water-swelling, water-insoluble organic or inorganic materials that are capable, under the most favorable conditions, of absorbing a mass of at least about 10 times their own mass, or at least about 15 times their own weight, or at least about 25 times their own weight, in an aqueous solution containing 0.9 weight percent sodium chloride. In absorbent products such as diapers, incontinence diapers, etc. the particle size is usually from 100 to 800 µm, preferably from 300 to 600 µm, most preferably from 400 to 500 µm.

The term "target zone" refers to the area of the absorbent core that is particularly desirable for initial contact with the majority of the ejected fluid, such as urine, menses, or feces. Specifically, for an absorbent article using one or more spillage receiving points, the target spillage receiving area refers to an area of the absorbent core extending to a distance equal to 15% of the total length of the composite article from each spillage receiving point in both directions.

"Extension" involves a unidirectional force tending to cause a stretch in the body, or a countervailing force in the body that opposes that stretch.

The term "thermoplastic" is intended to describe a material that softens when heated and returns to substantially its original state when cooled to room temperature.

The term "topsheet" refers to a liquid-permeable sheet of material forming the inner surface of an absorbent article and which, when in use, is placed in direct contact with the user's skin. The top layer is typically used to seal the user's skin from the liquid retained by the absorbent structure. The top layer may include a nonwoven material such as spunbond, meltblown, carded, water jet bonded, hydraulically bonded, etc. Suitable nonwoven materials may consist of man-made fibers such as polyester, polyethylene, polypropylene, rayon, cellulose man-made fiber, etc., or natural fibers such as wood pulp fiber or cotton fiber, or mixtures of natural and man-made fibers. In addition, the top layer material may consist of two types of fibers that can be bonded together in a specific bonding pattern. Other examples of topsheet materials include foams, perforated polymer films, laminates made from nonwovens and perforated polymer films, etc. Materials suitable as topcoat materials should be soft and non-irritating to the skin, and easily permeable to body fluids such as urine or menstrual fluid. The inner coating may further vary in different parts of the absorbent article. The topsheet fabrics may be composed of a substantially hydrophobic material, and the hydrophobic material may optionally be treated with a surfactant or otherwise treated to impart a desired level of wettability and hydrophilicity.

"Potty training panties" are used for children at the potty training stage, and are popular with mothers and caregivers. Potty training panties typically include a top sheet, a bottom sheet, an absorbent medium between the top sheet and the bottom sheet, and side seams securing portions of the side edges of the panty to form waist and leg openings.

As used herein, the term “transverse” or “lateral” refers to a line, axis or direction lying in the plane of the absorbent article and generally perpendicular to the longitudinal direction.

“Ultrasonic welding” refers to a technology that joins two materials by melting them under the heat generated by ultrasonic vibrations, and then layering them on top of each other so that the molten materials flow and fill the gap between the two unexposed parts of the two these materials, respectively. When cooled and molded, the two materials are bonded to each other.

"Dry state" refers to a state in which the absorbent article is not yet saturated with exudates and/or liquid.

"Wet state" refers to a state in which the absorbent article is saturated with exudates and/or liquid. Typically, the absorbent article will contain at least 30 ml, preferably at least 40 ml, even more preferably at least 50 ml, most preferably from 60 ml to 800 ml of exudate and/or liquid.

The term "water-swellable, water-insoluble" is intended to refer to a material that, when exposed to excess water, swells to equilibrium volume but does not go into solution. Thus, it is understood that a water-swelling, water-insoluble material generally retains upon water adsorption its original identity or physical structure, but in a highly expanded state, and thus must have sufficient physical integrity to resist the flow of adjacent particles and merging with them.

By "wrapping material" as used herein is meant a bendable material, preferably a sheet material, the thickness of which is less, preferably much less than its width and length, such as sheet, film or foil. In a particularly preferred embodiment, said wrapping material can be rolled.

As used herein, the term “concentration” (for example, of superabsorbent polymer) means the amount of said material divided by the surface area of said layer (which area is typically in the plane of the length and width of the core) on or within which said material is located. . It can be determined by standard weighing and sizing methods known in the art and can be expressed in g/mm ² .

As used herein, the term “substantially U-shaped” is meant to mean any shape that visually resembles a “U” shape, such as a “V-shape,” a semicircle, and the like.

As used herein, the term "individual cellulose fibers" means cellulose fibers that are not part of the substrate (e.g., nonwoven layer) and are sufficiently distinct from and/or physically separated from it, typically in the form of cellulose fibers that are enclosed within , but are located separately from the specified substrate. For clarity, cellulose fibers present in the substrate (eg, nonwoven fabric layer) are not included in its meaning.

As used herein, the term “substantially follows the shape of the channel(s)” means that said element has an overlapping shape that is visually similar to the shape of the channel(s).

As used herein, the term “superabsorbent polymer fibers” refers to fibers derived from superabsorbent polymers (as opposed to particles derived from them). Examples of fibers suitable for use in the present invention are selected from the fibers of Example 1, Example 2, Example 3 and/or Example 4 (page 5, lines 1-46) of application EP3190216A1, incorporated herein by reference. These fibers are usually used to produce non-woven fabrics according to the same mentioned application.

Next, embodiments and methods according to the present disclosure will be described. It should be understood that the technical features described in one or more embodiments may be combined with one or more other embodiments without departing from the purpose of the invention and without generalizing them. Absorbent core

The absorbent cores 101, 501, 601 according to the present invention may include: a front portion 122, a rear portion 124, a middle portion 126 located between the front portion 122 and the rear portion 124, and a longitudinal axis located along the length of said core 101, 501, 601 and intersecting said front, middle and rear portions 122, 126, 124, an absorbent core 101, 501, 601 having a width extending perpendicular to said length and a perimeter including at least two opposite ends 102, 103, and at least two opposing sides 104, 105 located between said ends 102, 103, wherein said core 101, 501, 601 is a multi-layer core comprising at least two separate core layers 502, 503, 602, 603, wherein the first core layer 502 , 602 comprises a first concentration of superabsorbent polymer 504, 604, and a second core layer 503, 603 comprises a second concentration of superabsorbent polymer 504, 604, wherein said first and second concentrations are different, wherein at least said first core layer 502, 602 includes one or more channels 106, wherein said channel(s) 106 are continuous and interconnected along at least the length and width of said core 101, 501, 601 such that at least portions of two channels 107, 108 extending beyond said length are within fluid connection via a channel connecting portion 109 located close to said rear portion 124.

The advantage of this arrangement is that the core achieves synergistic and efficient liquid distribution and absorption, with the shape of the channels providing instantaneous redistribution of liquid along the length and width of the core, especially from the front to the back of the product, and the multi-layer structure of the core with varying concentrations superabsorbent polymer allows for more efficient absorption of these liquids along a multifold path and reduces the risk of gel blocking.

Preferably, said channel(s) 106 do not extend beyond any of the edges constituting the perimeter of the absorbent core 101, 501, 601.

Preferably, the connecting portion of the channel 109 forms a substantially U-shaped bend, preferably at the location where the first layer of the core 502, 602 contains one channel 106. This shape allows the liquid distribution properties of the core to be optimized.

Preferably, channel(s) 106 includes one connecting portion of channel 109 such that a continuous region of superabsorbent polymer is formed around said channel(s) (typically in the core length/width plane) and typically does not enclose portions of said channel(s) 106 completely incorporating the region of superabsorbent polymer. This configuration allows for optimal fluid distribution while limiting the risk of over- and under-saturated regions in the core, and also reduces the risk of delamination of the layers connected to each other to form the channel(s).

Preferably, at least one of the interconnected channels 106, preferably each of said channels 106, takes the form of an open end in the form of two diverging ends in the shape of an hourglass, and with a closed end located opposite it formed by the connecting part of the channel 109, preferably where the open end is located closer to the front part 122 of the absorbent core 101 and further from the specified closed end. Benefits include faster fluid distribution from the front to the back of the product.

Preferably, the first core layer 502, 602 includes at least one wrapping substrate 505, 506, 605, 606, within which a superabsorbent polymer is located, and wherein the top wrapping material layer 505, 605 is adhered to the bottom wrapping material layer 506, 606 in areas of said cores that include channel(s) 106, preferably such that said channel(s) 106 preferably does not contain superabsorbent polymer 504, 604 (i.e. less than 1 wt.%, preferably less than 0.5 wt.%, more preferably less than 0.1 wt%, even more preferably less than 0.05 wt%, most preferably less than 0 wt% by weight of the insulating substrate). This ensures that fluids can flow quickly along the channel without swelling/absorption slowing their movement.

Preferably, the first core layer 502, 602 also contains individual cellulose fibers 507, 607 in admixture with superabsorbent polymer 504, 604, and where the second core layer 503, 603 does not contain said individual cellulose fibers 507, 607. This configuration allows for additional "localized" » liquid distribution through individual cellulose fibers that conduct liquid to the superabsorbent polymer dispersed therein for subsequent absorption and entrapment by the latter.

Preferably, the second core layer 503, 603 contains substantially no wool, but rather comprises a nonwoven carrier comprising a top carrier layer 508, 608 and a bottom carrier layer 509, 609, and a superabsorbent polymer therebetween, wherein said superabsorbent polymer is in the form of particles immobilized in said carrier, and wherein the upper carrier layer 508, 608 is a carded nonwoven fabric made from staple fiber or spunbond meltblown spunbond nonwoven material, and wherein said bottom carrier layer 509, 609 is a carded nonwoven fabric made from staple fiber or nonwoven fabric spunbond meltblown spunbond (preferably where said top and bottom layers of the carrier are different), preferably where the top and bottom layers of the carrier are mechanically bonded to each other, preferably by hydraulic interlocking, preferably where the top layer of the carrier 508, 608 consists of staple fibers permeable to particles of superabsorbent polymer , and the bottom carrier layer 509, 609 consists of a nonwoven material hydraulically bonded to said top carrier layer 508, 608. This configuration allows for a wool-free core layer comprising immobilized superabsorbent particles that maintain their position, thereby limiting the volume of the product and maximizing the absorption and liquid-locking properties of a given layer.

Preferably, the second core layer 503, 603 does not contain a wrapping material, but rather contains a single layer of nonwoven carrier having a superabsorbent polymer immobilized thereon or therein, wherein the nonwoven carrier layer is porous and the superabsorbent polymer is particulate and immobilized by mechanical action such such as ultrasound, one or more adhesives, and combinations thereof. This configuration has been found to have the advantage of reducing the additional volume and raw material required to produce the core. In particular, by trapping the particles in the substrate, for example using ultrasound, such immobilization can be achieved without treatment with chemical adhesives and thus subsequently also reduce the risk of chemical contamination and/or the need for multiple/additional layers to enclose said particles in wrapping material.

Preferably, the second concentration of superabsorbent polymer 504, 604 may be greater than the first concentration of superabsorbent polymer 504, 604, preferably wherein said second concentration is at least 1.5, preferably 2 times, the first concentration. This creates benefits such as a reduced risk of gel blocking.

Preferably, the second core layer 503, 603 is located below the first carrier layer 502, 602, and wherein said second carrier layer 503, 603 includes a first region of superabsorbent polymer particles 504 on its surface that is opposite to said first core layer 502, 602, wherein said the first region is arranged in a pattern that substantially follows the shape of the channel(s) 106, at least along a plane defined by the length and width of the core, such that the shape of the channel(s) 106 substantially matches the shape of the pattern. Typically, where the first region of superabsorbent polymer particles is the only region of the second core layer 503, 603 containing superabsorbent polymer particles, preferably where the second core layer 503, 603 contains superabsorbent polymer fibers different from the fibers in said first region, wherein said the first region does not contain said superabsorbent polymer fibers. This configuration allows for the dual performance of maximizing absorption effects on the core surface, as well as obtaining a multisensory (eg, visual and tactile) signal of core saturation.

Typically, the second core layer 503, 603 does not contain cellulose fibers and preferably consists of superabsorbent fibers or a mixture of superabsorbent fibers (described in the present invention) and synthetic fibers.

Preferably, the second core layer 503, 603 has a smaller plane size corresponding to the length and width of the core than the first core layer 502, 602. This allows the balance between production needs and application, as well as raw material costs, to be optimized.

Absorbent cores 101 according to the present disclosure may include: a front portion 122, a rear portion 124, a middle portion 126 located between the front portion 122 and a rear portion 124, and a longitudinal axis located along the length of said core 101 and intersecting said front, intermediate, and a rear portion 122, 126, 124, wherein the absorbent core 101 has a width perpendicular to said length and a perimeter including at least two opposing ends 102, 103 and at least two opposing sides 104, 105 located between said ends 102, 103, wherein the absorbent core 101 includes one or more, optionally substantially interconnected channels 106 having a first shape when the absorbent core 101 is in a dry state, and a second shape when the absorbent core is in a wet state, and wherein said first and second shapes are different. The inventors have found that this configuration provides a more effective alternative to standard visual wetness indicators that use a simple color change to provide such an indication. Indeed, the change in channel shape in dry/wet conditions provides not only an immediate visual indication, but also a tactile one, combining both sensations to provide the caregiver with a clear warning that a given absorbent article needs to be replaced.

In one embodiment, the first and second shapes are visually distinguishable and positioned to provide a visual and/or tactile indication that said core is saturated with exudates.

Preferably, the absorbent core includes one substantially interconnected channel 106 in a dry state, and more preferably, multiple (usually two) individual channels 206 in a wet state.

In one embodiment, the interconnected channel 106 includes a U-shaped bend near the rear end of the absorbent article and the first/second terminal ends 110,111 near the front of the absorbent article, generally in a dry state, and in a wet state (ie, when saturated with exudates and/or or liquid), the channel is divided into a plurality (preferably two) of individual channels 206, and typically said individual channels 206 do not have said U-bend.

In a preferred embodiment, as shown in FIG. 18A, when dry, the interconnected channel 106 includes first/second terminal ends 110,111 arranged in a divergent manner to form an open and/or funnel-shaped end opposite a closed end formed by a U-shaped bend. The advantage of this form is to increase the speed, first of all, of liquid distribution in the early stages of ejection.

When wet, the channel described above is positioned to change its shape, as shown in FIG. 18B, where one interconnected channel is converted into a plurality (preferably two) of unconnected channels substantially free of said U-bend. Preferably, the shape of the channels in the wet state is similar to their shape in the dry state, except for the absence of a U-shaped bend, so that one channel (in the dry state) becomes two channels (in the wet state). This typically occurs by breaking the connection that forms the U-shaped portion of the channel as the absorbent material expands to absorb liquid.

Such a change in shape can be achieved in various ways, which will be described below as preferred, although not limiting, embodiments.

In one embodiment, the core includes at least one wrapping substrate enclosing one or more absorbent materials; preferably, said absorbent material is selected from the group consisting of superabsorbent polymers, cellulose fibers, and combinations thereof, and wherein the top layer of wrap material is adhered to the bottom layer of wrap material to form interconnected, absorbent-free channel(s) 106 (typically dry). Typically, the areas where the top and bottom layers are not bonded have absorbent material between them (usually separating the top layer and the bottom layer), and the areas where the top and bottom layers are bonded together contain virtually no absorbent material. forming channels in the absorbent core material. Preferably, the bonded top and bottom layers of wrap material include a first bond in at least two separate areas of the channel(s) 106, and a second bond in at least one other region of the channel(s) 106 connecting the at least two separate area, and wherein said second bond is provided in such a way that it is broken by liquid saturation and/or expansion of the absorbent material, while the first bond is provided in such a way as to remain unaffected by liquid saturation and/or expansion of the absorbent material, preferably wherein said the other area is a U-shaped bend of the channel(s). More preferably, the channel is configured such that when dry, one or more, preferably one, interconnected channel 106 is visible, and when wet, multiple, preferably two, separate channels 206 are visible. However, it is obvious that the presence of a wrapping layer (although preferred) ) is not necessary to achieve this effect, and other methods can be considered, such as similarly bonding the top layer directly or indirectly to the bottom layer without the need for a wrapping material (thus the same features described above can be exhibited/replaced by top layer/bottom layer instead of wrapping material).

The first and second bonds may include first and second adhesives, respectively. The first and second adhesives are different, for example, the second adhesive is selected so that it dissolves upon contact with a liquid at body temperature (about 37°C), for example, it may be contact hot melt adhesives with a low melting point (i.e., with a melting point of about 40 °C) type 3798LM sold by 3M Company. The first adhesive can be selected from hot melt adhesives that maintain adhesive strength even in contact with liquid at body temperature (i.e. have a melting point above 60°C, preferably above 70°C, even more preferably above 90°C), such as Technomelt DM Cool 110 Dispomelt (also known as Dispomelt Cool 110), sold by Henkel AG & Co. KGaA, or VV290F, sold by Savare' Specialty adhesives. In the configuration described above, the second adhesive can be applied in the U-bend area, while the first adhesive can be applied in all other areas of the channel.

In an alternative embodiment to that described above, the same adhesive can be used along the entire channel, but in areas that must be released when wet, less pressure is applied when applying the bonding force between the substrates. For example, the pressure applied to a U-bend may be less (preferably half as much) than the pressure applied to all other sections of the channel.

Although the embodiments described above are examples of obtaining channels of various shapes in a dry/wet state, other ways of achieving the configuration of the invention can be considered and accordingly, the present application should not be limited in this way, for example, the first and second bonding may provide the first and a second bond strength, respectively, where the first bond strength is greater than the second bond strength. The term "bonding strength" used is preferably defined herein as "peel strength".

Typically, the peel strength of the first bond is greater than 5 g/mm, preferably greater than 6 g/mm, even more preferably 7 g/mm to 50 g/mm, and the peel strength of the second bond is below 5 g/mm, preferably from 0 .1 g/mm to 4 g/mm, more preferably 0.2 g/mm to 3.5 g/mm, even more preferably 0.3 g/mm to 3 g/mm, where the peel strength is usually determined according to the American Society for Testing and Materials (ASTM): D1876-72, "Standard Test Methods for Peel Resistance of Adhesives (T-Peel Test)", which is incorporated herein by reference.

In a preferred embodiment, the first fastener has a first hanger shear value, and the second bond has a second hanger shear value, where the first hanger shear value is greater than the second hanger shear value, wherein the hanger shear value is determined using the shear determination test described herein in suspension. Preferably, the first suspension shift value is greater than 14 minutes (min), preferably 15 min to 40 min, more preferably 20 min to 35 min, even more preferably 22 min to 29 min. Preferably, the first value of the suspension shift is less than 14 minutes, preferably from 0.5 minutes to 10 minutes, more preferably from 1 minute to 5 minutes.

Absorbent cores 101 according to embodiments of the present disclosure may include: a front portion 122, a rear portion 124, an intermediate portion (also referred to herein as a "middle portion") 126 located between the front portion 122 and the rear portion 124, and a longitudinal axis directed along the length said core 101 and intersecting said front, intermediate and rear portions 122, 126, 124, wherein the absorbent core 101 has a width perpendicular to said length and a perimeter including at least two opposite ends 102, 103 and at least two opposite sides 104, 105 located between said ends 102, 103, wherein the absorbent core 101 comprises one or more substantially interconnected channels 106 extending through at least a portion of the intermediate portion 126 (preferably at least 60%, more preferably at least through 70%, even more preferably at least 80% of the intermediate portion, extending substantially parallel to the longitudinal axis) along the long side of the core and along at least a portion of said core width, typically along and substantially parallel to the longitudinal axis, and from one side a core [eg, first side 104] to another [eg, second side 105], wherein preferably said one or more substantially interconnected channels 106 are symmetrical or asymmetrical along the longitudinal axis.

The advantage of this configuration of interconnected channels is to achieve faster distribution of fluid throughout the core compared to a core containing no such interconnected channels or a core containing only non-interconnected channels. This helps limit oversaturation of the core in the area of liquid ejection. Without wishing to be bound by theory, it is believed that by allowing the liquid to spread through the core and immediately move away from the point of release, the user will experience a feeling of dryness and skin comfort, as well as a feeling of longer-lasting dryness.

The described longitudinal axis of the core may be substantially parallel to the longitudinal direction 48 and can be used interchangeably (as shown in FIG. 11 and FIG. 12), and the described core width or transverse axis of the core may be substantially parallel to the lateral direction 49 (also referred to in the description as a transverse axis) and can be used interchangeably in the description (as shown, for example, in Fig. 11 and Fig. 12).

In one embodiment, the one or more interconnected channels are shaped to effectively drain fluid away from the discharge region, typically by shaping them such that there is a distance gradient between the opposing surfaces of the interconnected channels, preferably by giving them a funnel shape.

In one embodiment, the channels form a geometric pattern within the absorbent core and along a plane parallel to the longitudinal axis of said core, said geometric pattern being selected from the group consisting of half hourglass, V-shape, U-shape, in the form of a sector of a circle, and their combinations. Meanwhile, “half-hourglass shape” means an hourglass shape with only one end; Examples of shapes are shown in Fig. 4.

In one embodiment, the channels include, preferably consist of, a first nonwoven fabric bonded to a second nonwoven fabric by one or more adhesives. Preferably, the adhesive is applied in zones located across the width of the channels to form zones, preferably alternating zones, of varying bond strength in the laminated nonwoven fabric structure. For example, the first nonwoven fabric may be bonded to the second nonwoven fabric in at least three zones along the width of the channel. Such a configuration may include a first bonding zone, a second bonding zone, a third bonding zone, wherein the second bonding zone is located between the first and third bonding zones along the width of the channel (for example, along an axis parallel to the width of the core and perpendicular to the longitudinal axis of the core), where the bond strength the second gluing zone is greater than the bonding strength of the first and third gluing zones. Examples of methods for achieving such high bond strength in the second zone include using larger amounts of adhesive in that zone, applying more mechanical pressure to that zone, or using a different type of adhesive, and other methods are also contemplated to provide stronger bonding of the nonwoven webs in that region.

In one embodiment, the bond strength in the first and third zones is less than the tensile force generated by the absorbent material located adjacent to the channel when wet, so that the first and second nonwoven webs can be separated in these zones, and where the bond strength in the second zone is higher than a tensile force generated by the absorbent material proximate the channel when wet, such that the first and second nonwoven webs may not separate in said area when the absorbent material becomes wet and generally swells, but may instead remain firmly attached. The advantage of this configuration is that in dry conditions a prominent channel is visible from the top side of the product and/or core, providing wide channels which are further useful for carrying more liquid through the channels, especially during initial/early ejection. In addition, this configuration does not allow for bonding in the first and third regions, for example, when SAP swells, so that when they expand, more volume is available (and can prevent early saturation or suboptimal absorption), while the second zone usually resists such expansion and , thus ensuring the integrity of the channels even when wet.

In a preferred embodiment, the first nonwoven fabric and/or the second nonwoven fabric, preferably the second nonwoven fabric, are elastic nonwoven materials (for example, containing an elastic material such as Vistamaxx polymer from ExxonMobil, or other suitable polymers capable of imparting elasticity to the nonwoven fabric) . The advantage of this embodiment is that the nonwoven web wraps better and more easily around the 3D insert when vacuum is applied and allows for subsequent attachment to the first nonwoven web at a location corresponding to the position of the 3D insert backing (opposite its projecting apex). This has the advantage of limiting the formation of reservoirs of collected fluid or depressions in the channels.

The cores described in the disclosure have a substantially straight perimeter such as that shown in FIG. 1 and fig. 2, or may include symmetrical concave portions in the middle region, as shown in FIG. 3. In the latter embodiment, the concave portions may coincide with and/or be located in the intermediate region to provide better ergonomics and fit to the user's foot. In any of the embodiments of these core shapes, it is preferred that said cores are symmetrical at least along their longitudinal axes. Regardless of the core geometry, it is understood that the same or similar channels can be used interchangeably.

In one embodiment related to FIG. 1 according to FIG. 3, at least one and preferably each interconnected channel 106 includes: a first channel portion 107 extending substantially along a longitudinal axis proximate a first side 104 of the core 101, a second channel portion 108 extending substantially along a longitudinal axis proximate a second side 105 of the core 101, and at least one, preferably only one, connecting channel portion 109 in fluid communication with said first and second channel portions 107, 108. This configuration has the advantage of rapidly distributing liquid along more than one axis of the absorbent core, typically along both its longitudinal axis and its transverse axis in order to maximize the absorption capacity of the absorbent core over its entire surface area. Additionally, this geometry improves the foldability of the core and thus allows for a better and more comfortable fit to the subject's skin (with the addition of additional elastic material closer to said portions of the channels).

Thus, the connecting part of the channel 109 of at least one of the interconnected channels, where this connecting part of the channel is in fluid connection with the specified first and second parts of the channels 107, 108, preferably forms the specified closed end in the form of a U-shaped bend, preferably wherein the first and second portions of the channels 107, 108 diverge from the longitudinal axis along a portion of the interconnected channel 106, generally extending from a U-shaped bend, thereby at least partially forming a funnel-shaped interconnected channel adjacent the closed end.

The first and second channel portions may be substantially linear or have a substantially curved profile, preferably selected from concave or convex, or may include a combination of said linear and curved profiles. In a preferred embodiment, the first and second channel portions are concave in shape and generally symmetrical at least along the longitudinal axis.

The first and second channel portions may extend through at least a major portion, preferably the entire length of the intermediate portion along the longitudinal axis, and typically extend substantially parallel to the sides of the core, defining its perimeter.

In the most preferred embodiment, each interconnected channel described herein includes only one connecting channel portion 109, typically forming the top of the interconnected channel. This embodiment has the advantage of quickly distributing the liquid throughout the core, while minimizing the risk of blockages that might otherwise occur if patches of wetted areas were instead formed.

Preferably, the connecting portion of the channel 109 extends substantially along the width of said core 101, preferably forming a closed end within the surface of said core 101 along a plane parallel to the longitudinal axis, and preferably located opposite the open end formed by the non-connecting first and second terminal positions 110, 111 of the interconnected channel 106, preferably the first and second portions of the channels 107, 108, respectively, wherein typically said non-connecting first and second terminal positions 110, 1a11 are located at some distance from each other and close to the first and second sides 104, 105 of said core of 101, accordingly, even more preferably, said terminal positions 110, 111 are turned away from each other to form a funnel-shaped geometric open shape between them. Without wishing to be bound by theory, it is suggested that this geometry allows for the formation of a “funnel” and the accumulation of more liquid where it is needed, and effectively distributes it out of the accumulation area.

In one embodiment, and preferably in combination with the preceding embodiment, the interconnected channel includes unconnected first 110 and second 111 terminal positions, whereby the first terminal position 110 extends to the first core side 104, and/or the second terminal position 111 extends to the second core side 105, as, for example, shown in FIG. 3. In this case, the entire width of the absorbent core can be covered by a channel, which guarantees more efficient liquid distribution.

In one embodiment, the closed end has a substantially curved shape, preferably forming a convex figure between the first and second channel portions 107, 108, or has a substantially linear shape, preferably forming a straight or triangular figure between the first and second channel portions 107, 108. The closed end may be formed by the connecting portion of the channel 109. This shape has the advantage of increasing the surface area in contact with adjacent areas of the three-dimensional absorbent material, facilitating greater absorption of distributed liquid escaping from areas of typically high saturation.

In one embodiment, the first distance d ₁ between the first part of the channel 107 and the second part of the channel 108, the second distance d ₂ between the first part of the channel 107 and the second part of the channel 108, where the first distance d ₁ is closer to the front part 122 of the core 101, and the second the distance d ₂ is closer to the rear portion 124 of the absorbent core 101, and where the first distance d ₁ is greater than the second distance d ₂ , preferably where the first distance d ₁ is at least 1.5d ₂ , more preferably from 1.8d ₂ to 3d ₂ . The advantage is the rapid and efficient distribution of liquid from an area of typically high saturation towards areas of typically low saturation.

In one embodiment, the core comprises a first nonwoven web, typically in the form of a backsheet, a second nonwoven fabric, typically in the form of a topsheet, and three-dimensional absorbent material disposed between the first and second nonwoven webs to form a laminated absorbent core, typically wherein the three-dimensional the absorbent material includes a fibrous web, typically containing air-spun fibers, and preferably includes a predetermined amount of superabsorbent polymer dispersed therein.

In the most preferred embodiment, the interconnected channel 106 is substantially free of three-dimensional absorbent material and preferably free of superabsorbent polymer. Without wishing to be bound by theory, it is believed that absorbent materials slow down liquid distribution relative to the efficiency of such channels; indeed, as absorbent materials absorb liquid, they swell and/or become saturated, effectively reducing the amount of liquid that could pass through them. The exclusion of such materials from the channels allows for the maintenance of a highly efficient fluid distribution system that operates substantially independently of the intake/absorption mechanism of adjacent areas.

In a preferred embodiment, the core includes a plurality of substantially interconnected channels, preferably arranged in a substantially concentric manner, for example as shown in FIG. 4E. The advantage of this is the exponential efficiency of fluid distribution and channel formation, particularly as adjacent areas become more saturated and or swollen.

In one embodiment, as shown in FIG. 4C and 4D, the core also includes one or more non-coupled channels, preferably at least a portion thereof arranged in a concentric manner relative to the substantially interconnected channel. The advantage of this is the effective additional local uniform distribution of the liquid. In addition, it is hypothesized that swelling of areas adjacent to the channels may create visually noticeable patterns that more clearly convey the perception of the effectiveness of the entire core surface for liquid absorption.

Preferably, the substantially interconnected channels 106 have a constant or variable depth, measured along an axis perpendicular to both the longitudinal axis and an axis extending along the width of the core 101, preferably wherein the cross-section of said channels is selected from the group including curved, polygonal shapes, or a combination of them.

In the preferred embodiment illustrated in Figure 16, the width of the interconnected channel(s) 106 may vary along the channel. Preferably, the width of the channels decreases from the terminal positions 110, 111 towards the connecting part of the channel 109. This is shown in FIG. 16, where the width 210a of the channel 106 adjacent the first terminal position 110 and the width 210b of the channel 106 adjacent the second terminal position 111 are greater than the width 211a of the channel 106 in the first part of the channel 107 and the width 211b of the channel 106 in the second part of the channel 108, which are larger, than the width 212 of the channel 106 in the connecting portion 109. Such variability in the width of the channel portions results in faster distribution. Without wishing to be bound by theory, the inventors believe that varying the width increases capillary effects which promote more efficient fluid transfer from the front to the back of the absorbent article.

It will be appreciated that a number of alternative shapes can be used for the channels described herein, examples of which are shown in FIGS. 4 and fig. 16, without going beyond the scope of the embodiments of the invention described herein.

Additionally, the present disclosure relates to an absorbent core 101 including substantially continuous zones of one or more large volume liquid distribution structures 112 and continuous or discrete zones of liquid absorbent structures 113, 114 surrounding one or more large volume liquid distribution structures 112. a liquid volume wherein one or more large volume liquid distribution structures 112 are arranged to distribute liquid across the absorbent core 101 at a rate that exceeds the rate of liquid distribution across the absorbent core by said discrete liquid absorbent structures 113, 114, and where said continuous zones extend substantially parallel to at least a portion of the perimeter of the core 101, wherein said portion of the core perimeter comprises at least a portion of the sides 104, 105, preferably at least a portion of both sides 104, 105 of the core 101, and one of the edges 102, 103 of the core 101 ( preferably only one edge 103), with edge 103 preferably located close to the rear portion 124. Advantages of this embodiment include separating the absorbent regions of the core by liquid distribution regions that effectively distribute liquid evenly across the surface of the core using the mechanism described above, and also providing a visual perception of efficiency.

In one embodiment, the liquid distribution structures are shaped to effectively conduct liquid away from the ejection area, typically by forming a shape having a gradient of distance between opposing surfaces of said structures, preferably forming a funnel-shaped profile substantially defined by one or more liquid absorbing structures .

In one embodiment, the large volume liquid distribution patterns form a geometric shape throughout the absorbent core and along a plane parallel to the longitudinal axis of said core, said geometric shape being selected from the group consisting of a half hourglass shape, V- shaped, U-shaped, shaped like a sector of a circle, and their combinations. By “half-hourglass shape” we mean an hourglass shape with only one end, such as that shown in FIG. 4B.

In a preferred embodiment, the one or more large volume liquid distribution structures comprise, preferably consist of, at least two nonwoven webs bonded together (e.g., by an adhesive), and the zones of the liquid absorption structures comprise a three-dimensional absorbent material (such as cellulose wadding and/or fibrous web, typically containing air-spun fibers, typically of the cellulose type) and/or superabsorbent polymer (usually in the form of a plurality of discrete particles that can be distributed throughout the three-dimensional absorbent material or directly agglomerated on one or more areas at least between two non-woven fabrics).

Preferably, said liquid distribution structures include the substantially interconnected channels described in the preceding embodiments, and the liquid absorbent structures include the three-dimensional absorbent material and/or superabsorbent polymer described in the preceding embodiments.

Absorbent Products

The absorbent articles 10, 20, 300, 500, 600 of the present disclosure include a core 101, 501, 601 positioned between a liquid-permeable topsheet 520, 620 and a liquid-impervious backsheet 521, 621, and typically an acquisition distribution layer 522 , 622 described in the disclosure, which is located between said top sheet 520, 620 and said core 101, 501, 601. Preferably, the back sheet includes an imprint or graphic image visible from the side of said article facing the garment, which substantially follows the shape and/or contour of the channel(s) 106. The advantage of the latter feature is to further emphasize the visual perception of the presence of such a channel and its location in the absorbent product.

Preferably, when saturated with exudates, the first region of the second core layer 503, 603 swells to form one or more projections 525 that are visible from the garment side of the article, said projections substantially following the shape of one or more channels 106, as rule to indicate to the caregiver that the absorbent article is saturated and should be replaced. This has the advantage of providing a clear, multi-sensory warning that the absorbent article should be replaced.

Preferably, the print or graphic includes a plurality of shades, with the darkest shade located such that when said article 10, 20, 300, 500, 600 is in a wet state, said darkest shade is at the top of each of the one or more protruding parts 525. The advantage of this is that gradual warning is provided, since as the size of the protruding parts increases during the swelling process, the darker shade becomes more obvious (visually) until a state of full saturation/increase.

In one aspect of the present invention, the absorbent core may include the core 101 described above, which article is preferably selected from disposable diapers or panties, disposable incontinence diapers or absorbent panties, sanitary napkins or pads, and typically the channel (s) in said core remain visible both before and after use of the article and have a first shape when the absorbent core 101 is in a dry state and a second shape when the absorbent core is in a wet state, said first and second shapes being different. Preferably, the channel(s) are visible from the clothing side and/or the skin side of the product, preferably visible when looking at the back sheet of the product from the clothing side. Preferably, the channels in said core remain visible both before and after use of the article, and preferably the channels are more visible after use of the article than before.

In one embodiment, the absorbent article includes a topsheet and a backsheet directly or indirectly enclosing a core, wherein at least one of the backsheet or topsheet has a different color from the core, preferably wherein the backsheet has a color different from the topsheet and core so that the channels can be visually distinguished from the topsheet side of the product.

Receiving and distribution layer

One particular component preferably used in the absorbent articles described in the disclosure is an acquisition and distribution layer (ADL). The ADL may be located on the body-facing side of the absorbent core, between the topsheet and the absorbent core of the absorbent article, and more preferably in close proximity to, or even in good contact with, the body-facing side of the absorbent core. The use of ADLs in combination with the liquid distribution structures and/or interconnected channels of the present invention results in extremely efficient distribution of liquids from the ejection region throughout the absorbent core, while achieving an excellent subjective dryness sensation.

In one embodiment, the acquisition distribution layer 522, 622 for use in the present invention includes a layer of spunbond and/or carded, preferably carded, thermally bonded nonwoven material comprising synthetic fibers, wherein said synthetic fibers are present in an amount greater than 80% by weight of said acquisition. distribution layer 522, 622, and wherein the basis weight of said receiving distribution layer 522, 622 is from 10 to 50 g/ ^m2 , preferably from 15 to 40 g/ ^m2 , more preferably from 18 to 35 g/ ^m2 , even more preferably from 20 to 30 g/ ^m2 , most preferably from 21 to 25 g/ ^m2 .

Preferably, the specific volume of the receiving distribution layer 522, 622 is less than 11.4 cm ³ /g, preferably less than 11.3 cm ³ /g, more preferably from 5.5 cm ³ /g to 11.2 cm ³ /g, more more preferably 8.5 cm ³ /g to 11.17 cm ³ /g. Preferably, the specific volume within these ranges allows the disadvantages associated with sponge-type re-wetting to be limited while still providing high reception rates when coupled to the channel-containing cores described in this invention.

Preferably, the synthetic fibers are contained in an amount greater than 90% by weight, preferably from 95% to 100% by weight, based on the weight of said receiving distribution layer 522, 622.

Preferably, the acquisition distribution layer 522, 622 consists of synthetic fibers and preferably does not contain cellulose fibers, more preferably wherein said acquisition distribution layer 522, 622 is treated, for example with a surfactant, to render said layer 522, 622 hydrophilic. Preferably, the synthetic fibers include, preferably consist of, polypropylene fibers. Preferably, dryness perception is increased by further eliminating cellulosic fibers from the ADL.

In one embodiment, the acquisition distribution layer 522, 622 consists of preferably a single layer spunbond or carded nonwoven material and does not contain layers of hot air bonded, dry air bonded, and/or meltblown nonwoven material.

Preferably, the receiving distribution layer 522, 622 has an average pore size of from 15 μm to 200 μm, preferably from 30 μm to 150 μm, more preferably from 45 μm to 130 μm, even more preferably from 55 μm to 110 μm, even more preferably from 60 µm to less than 100 µm, even more preferably from 65 µm to 95 µm, even more preferably from 70 µm to 90 µm. Without wishing to be bound by theory, if the pore size is too small, the nonwoven material will retain more liquid and will have reduced efficiency in terms of liquid removal, on the other hand, if the pore size is too large, the nonwoven material will not have the necessary absorbent properties to still provide acceptable liquid distribution throughout the core.

Preferably, the acquisition distribution layer 522, 622 includes a first center-located C _ADL and the absorbent core 101, 501, 601 includes a second center-located C _c , with the acquisition distribution layer 522, 622 positioned asymmetrically over the absorbent core 101, 501, 601 such that the first center-located C _ADL and the second center-located C _c are offset at least along the longitudinal axis 48, preferably where the receiving distribution layer 522, 622 is located so that it does not overlap with a portion of the channel 106, which extends transversely along an axis substantially perpendicular to said longitudinal axis 48. The advantage of this configuration is the reduction of raw material costs due to the fact that the ADL is placed where it is needed most and, in addition, due to the fact that part of the channel remains open (especially the U-shaped bend of the channel), the speed of fluid flow through the channel from front to back is not disturbed.

Preferably, the receiving distribution layer 522, 622 has a relative porosity of less than 9000 l/m ² /s, preferably from 1000 l/m ² /s to 8000 l/m ² /s, preferably from 2000 l/m ² /s to 7000 l /m ² /s, more preferably from 3000 l/m ² /s to 5000 l/m ² /s, most preferably from 3500 l/m ² /s to 4500 l/m ² /s. Preferably, nonwovens whose relative porosity is within these ranges reduce the sponge effect while maintaining good liquid distribution efficiency.

The inventors have found that liquid distribution in embodiments of an absorbent article according to some aspects of the present invention that include an ADL may depend on the relative size and location of the ADL relative to the liquid distribution structure, and in particular, the interconnected channels in the absorbent core.

FIGS. 17A-D illustrate embodiments including ADL 201 and its relative size and location relative to interconnected channels 106. FIG. 17A shows an embodiment in which the ADL 201 covers the entire channel(s) 106. Such a configuration is already an improvement over the prior region configurations since the combined effects of the ADL and the interconnected channel result in a significant improvement in the distribution of liquids throughout the absorbent core. However, the inventors have found that certain configurations further improve the efficiency of liquid distribution; these configuration options are shown in FIGS. 17B-D and will be discussed further below.

In fig. 17B shows a preferred embodiment in which the ADL 201 of the already interconnected channel 106 is positioned such that the first 110 and second 111 terminal positions extend beyond the side edges 202, 203 of the ADL.

In fig. 17C shows a preferred embodiment in which the ADL 201 is positioned such that the connecting portion of the channel 109 extends beyond the rear edge 204 of the ADL. The connecting portion of the channel 109 preferably includes or is shaped like a U-bend.

In fig. 17D illustrates a preferred embodiment in which the ADL 201 of the already interconnected channel 106, and is positioned such that the first 110 and second 111 terminal positions extend beyond the side edges 202, 203 of the ADL, and in which the ADL 201 is positioned such that the connecting portion channel 109 extends beyond the trailing edge 204 of the ADL. The connecting portion of the channel 109 preferably includes or is shaped like a U-bend.

A common feature of the configurations presented in Figures 17B-D is that some extreme points of the interconnected channel 106 are not covered by ADL and are thus closer to the user. Without wishing to be bound by theory, the inventors believe that these extreme points are very important to the operation of the interconnected channel 106 in distributing liquids from the ejection zone to areas of the absorbent core that normally remain unaffected, or at least partially exposed, to liquid ejections. By not covering some or all of the endpoints with the ADL, fluid inflow and/or fluid outflow for the interconnected channel is expected to be maximized. In addition, these embodiments make it possible to use a smaller ADL and therefore a smaller volume of raw materials in the absorbent article.

Methods of manufacture and use

The present invention also relates to a method for making an absorbent core, which may include the steps of:

i. providing a mold containing within a 3D insert, wherein said 3D insert has a shape inverse to the shape of the desired channels, wherein substantially the entire surface of the mold is in fluid communication with a source of reduced pressure, excluding the 3D insert,

ii. applying the first non-woven fabric to the specified form,

iii. applying a three-dimensional absorbent material to at least a portion of said nonwoven material,

iv. applying the second nonwoven fabric directly or indirectly to the three-dimensional absorbent material,

v. optionally employing a bonding step to form a laminate comprising said first nonwoven, said second nonwoven web and said three-dimensional absorbent material disposed therebetween,

vi. optionally removing said laminate from the mold to provide an absorbent core including channels having a shape inverse to that of said 3D insert, and

wherein at least during step iii, a source of reduced pressure is provided to create a vacuum force resulting in substantially removing said three-dimensional absorbent material around the 3D insert from its surface and forming channels substantially free of said three-dimensional absorbent material. Such a process has been found to be effective in forming channels substantially free of said three-dimensional absorbent material, compared to methods that employ embossing (i.e., creating channels of high-density/densified three-dimensional absorbent material) or material removal methods. which include the removal of three-dimensional absorbent material from the preformed core structure, which inevitably results in the presence of some amount of three-dimensional absorbent material, which may adversely affect the effective/uniform distribution of the liquid during the saturation process.

In fig. 15A and FIG. 15B shows an example of a shape including the 3D insert described above.

In one embodiment, the mold includes a plurality of perforations or holes on the surface, typically forming channels arranged to be in fluid communication (preferably air) with a source of reduced pressure. Preferably, the 3D insert is located on top of and/or above said mold surface including a plurality of perforations or holes, and said 3D insert does not contain said perforations or holes and includes a solid component not in fluid communication with source of low pressure.

Preferably, the 3D insert has a transverse shape selected from the group consisting of square, rectangle, oval, semicircle, and combinations thereof.

More preferably, the 3D insert has the same or variable depth throughout its perimeter.

In one embodiment, the 3D insert is 3D printed, preferably made from a material selected from alumina, or made from metal and manufactured by milling or casting.

In a preferred embodiment, the bonding step comprises applying an adhesive to the surface of a second nonwoven web and bonding said web to said first nonwoven web and/or three-dimensional absorbent material, wherein the adhesive is preferably applied in continuous or discrete discrete strips aligned with said channels. , such that the resulting laminated core includes adhesive-rich regions and adhesive-poor regions, wherein adhesive-rich regions are substantially located along said channels and adhesive-poor regions are located in portions of the core other than specified channels. This embodiment has the advantage of limiting the risk of the absorbent material sticking together within the channels and of bonding the top sheet and back sheet of nonwoven material to each other fairly directly at the locations of these channels.

In one embodiment, the adhesive is applied in zones across the width of the channels so as to form zones, preferably alternating zones, of varying bond strength between layers. For example, the first nonwoven fabric can be bonded to the second nonwoven fabric in at least three zones along the width of the channel. Such a configuration may include a first adhesive zone, a second adhesive zone, and a third adhesive zone, wherein the second adhesive zone is located between the first and third adhesive zones along the width of the channel (for example, along an axis parallel to the width of the core and perpendicular to the longitudinal axis of the core), where the bond strength of the second adhesive zone exceeds the bond strength of the first and third adhesive zones. Examples of methods for achieving such higher bond strength in the second zone include using larger amounts of adhesive in that zone, applying greater mechanical pressure to that zone, or using a different type of adhesive, while other methods are also contemplated, provided that this results in stronger adhesion between non-woven fabrics in a given area.

In one embodiment, the bond strength in the first and third zones is less than the tensile force generated by the absorbent material adjacent the channel when wet, such that the first and second nonwoven webs can separate in said zones when wet, and where the bond strength in the second zone exceeds the tensile force , generated by the absorbent material located near the channel when wet, so that the first and second nonwoven fabrics may not separate in the specified area when the absorbent material swells, but, on the contrary, may remain firmly attached. The advantage of this configuration is that, when dry, a prominent channel is visible from the top sheet of the product and/or core, providing wide channels, which are also useful for carrying more fluid through the channels, especially during initial/early release of fluid. In addition, such a configuration later prevents bonding in the first and third regions, for example, when SAP swells, so that more volume is available for their expansion (and to prevent early saturation or suboptimal absorption), while usually the second zone resists such expansion and thus ensures the integrity of the channels even when wet.

In a preferred embodiment, the first nonwoven fabric and/or the second nonwoven fabric, preferably the second nonwoven fabric, are elastic nonwoven materials (eg, containing an elastic material such as Vistamaxx polymer from ExxonMobil). The advantage of this embodiment is that the nonwoven web wraps better and more easily around the 3D insert when vacuum is applied and allows for subsequent attachment to the first nonwoven fabric at a location corresponding to the position of the base of the 3D insert (opposite its protruding apex). This has the advantage of limiting the formation of reservoirs of accumulated liquid or drainage within the channels.

More preferably, the channels are formed substantially only by said vacuum force and in the absence of additional mechanical action such as embossing.

In one embodiment, the adhesive is used such that, after lamination, the bonded first and second nonwoven webs at the channel locations are substantially flush with the non-bonded portions of the second nonwoven web, thereby limiting the formation of liquid retention areas in the final laminated core. This embodiment has the advantage of preventing the formation of fluid-containing areas that may reduce the subject's comfort level.

The shape described above may be within the circumference of a rotating drum device, said drum device typically comprising a plurality of said shapes around its circumference. Said drum device can be integrated into existing apparatuses for producing absorbent core laminates. The advantage of such a simple configuration is that it allows such new absorbent cores to be manufactured in a simple and efficient manner without the significant capital investment required to substantially modify major parts of existing core manufacturing equipment.

The invention also relates to the use of the absorbent core described in the previous sections in the absorbent article described above for improved liquid distribution compared to the same absorbent article containing a core substantially free of interconnected channels.

In addition, the present invention relates to the use of the absorbent core described in the previous sections in the absorbent article described above to provide a three-stage liquid reception, typically including a first liquid distribution at a first rate, a second liquid distribution at a second rate, and a third distribution fluid at a third velocity, wherein said first velocity is greater than or equal to said second velocity, and said third velocity is less than said first velocity and less than or equal to said second velocity, preferably wherein the driving force for the first fluid distribution is substantially interconnected channels, the driving force the second liquid distribution is the three-dimensional absorbent material contained in the core, and the driving force of the third liquid distribution is a certain amount of superabsorbent polymer dispersed in the three-dimensional absorbent material. Without wishing to be bound by theory, it is believed that the new cores described herein, incorporating the described new configuration of interconnected channels, achieve a unique and first-of-its-kind separate distribution of liquid and absorption system, whereby, firstly, the channels provide rapid distribution /removal of liquid from the ejection area followed by further distribution from adjacent surfaces of the channels to other parts of the core through the three-dimensional absorbent material and, finally, the superabsorbent polymer dispersed in the three-dimensional absorbent material, under the influence of the liquid, begins to absorb said liquid, at the same time swelling, providing allowing the three-dimensional absorbent material to distribute and transfer more of said liquid to the superabsorbent polymer.

Suspension Shear Test Method:

The core (unused, i.e. in a dry state) comprising the channel described above is cut into several samples measuring approximately 5 cm x 10 cm, as shown in FIG. 19A (as shown in the Figure, sample 3 represents the U-shaped part of the channel, and samples 1 and 2 represent the other parts of the channel). Each sample is then kept at room conditions (usually an oven at 25°C and 40% RH for at least 12 hours).

The top and bottom substrates of each sample are peeled off up to (and not including) the channel location (the place where both the top and bottom substrates are secured to each other), and the bottom substrate is secured using a stationary clamp, and the top substrate is secured using a second clamp from which weights with a total mass of 109 g are suspended for each sample (as shown in Fig. 19B).

After this, the time interval from the moment the load is applied until the moment when a complete rupture between the upper/lower substrates occurs (that is, at the moment the load falls) is recorded. The last time reading represents the gimbal shift value.

The invention is further described by way of the following non-limiting examples, which further illustrate the invention and are not intended and should not be construed as limiting the scope of the invention. The examples provided provide further embodiments and structural technical features that can be included (singly or in combination) in absorbent articles according to the present disclosure. However, it should be understood that alternative structural features may be used without departing from the patentability of the present invention.

Reception time testing method:

The following test is carried out to determine the fluid intake time of the diaper.

A mass of 8 kg is loaded into the core of the diaper. A certain amount of NaCl solution is poured into the diaper using a special funnel and the absorption time is measured. This procedure is repeated a total of four times, with a 5-minute interval after each injection.

Solutions used: demineralized water (conductivity < 5 µS/cm), colored NaCl solution (0.9%) [9 g sodium chloride, analytical grade NaCl. dissolved in 991 g of demineralized water and colored with food coloring that does not contain table salt].

Equipment used: foam mat covered with hook material, 8 kg weight with funnel on top (base area 100 mm x 300 mm, approximately 0.4 psi), digital clock (accuracy 1 sec per 20 min), scales (accuracy ± 0.01 g), filter paper according to Hy-Tec (100 mm x 300 mm; Schleicher & Schuell type 604); Baker.

Sample preparation: At least four unused diapers were tested. The mass of each sample was determined and recorded. Weighted filter paper (10 pieces) to study the flow through the bottom sheet was placed on foam mats before fixing the samples on them. The insertion point was marked on the diaper according to the position according to gender, i.e. in the center of the diaper for a girl, 2.5 cm closer to the front for the universal version and 5 cm closer to the front for the boy. Then the filter paper was placed so that its center was at the injection point.

Method: The diaper is placed over the filter paper so that leakage occurs through the bottom sheet onto the foam mat. Place an 8 kg weight on the absorbent core so that the mark on the side matches the mark on the diaper. NaCl solution (4 x 70 ml) is poured onto the diaper through a funnel. The time required for the liquid to penetrate the top sheet is determined and recorded. Once the liquid has been absorbed into the diaper, the countdown begins to determine the waiting period. After a 5-minute waiting period, the same amount of liquid is poured into the diaper a second time and the absorption time is again determined and recorded. This procedure is repeated a total of four times. After the fourth 5-minute waiting period, the weight is removed from the diaper and any liquid remaining on the base plate is wiped off.

Based on the results for the products tested, the mean and standard deviation for the absorption time (in seconds) after the fourth addition of liquid is reported as the mean ingestion time.

Method for assessing surface dryness (rewetting):

The following test was carried out to determine the surface dryness of the diaper.

A certain amount of NaCl solution is poured into the diaper at one time from a measuring cylinder. The time required for fluid absorption is recorded.

Two minutes after injection, the rewetting should be determined at a load of 580 g using filter paper, which is weighed before and after testing and the values recorded.

Solutions used: demineralized water (conductivity < 5 µS/cm), colored NaCl solution (0.9%) [9 g sodium chloride, analytical grade NaCl. dissolved in 991 g of demineralized water and colored with food coloring that does not contain table salt].

Equipment used: plastic box (37cm x 26cm x 17cm), metal sheet and magnets, plexiglass plate (25(±1)cm x 20(±1)cm; 580±2g), electronic clock (accuracy 1 s for 20 min), balance (accuracy ±0.01 g), filter paper according to Hytec (14 cm x 19 cm; Schleicher & Schuell 604), measuring cylinder (volume ≥ 100 ml).

Preparation of samples: diapers (at least 5 samples of each) are placed in a transparent box in a curved form, fixed with metal clips at the edges/borders of the box. It is assumed that the core is completely inside the box, and the edges of the core do not extend beyond the walls of the box.

Method: Place 100 ml of NaCl solution in a measuring cylinder and place it over the middle of the diaper. The liquid is quickly poured into the diaper in one go and the countdown begins. One minute after pouring out the liquid, the diaper is placed unfolded on a metal plate using four magnets placed along the edges of the diaper. After a total of two minutes, the pre-weighed filter paper and plexiglass plate are placed in the center of the diaper. The stack of filter paper and plexiglass plate remain on the diaper for 5 seconds. After this, the filter paper is weighed again. The difference in mass of filter paper before and after testing is equal to rewetting in grams. Rewetting is calculated using the following formula: Rewetting [g] = W A - W B

where W B = weight of the filter paper before testing, and W A = weight of the filter paper after testing.

The average rewetting is then reported as the average of all samples tested (values in g).

Breathability testing method:

The following testing method is carried out to determine the air permeability (or "relative porosity" as it is called herein) of nonwoven substrates.

Equipment used: air permeability tester model FX 3300 LABOTESTER III (from Textest AG), equipped with a test head with lot number FX 3300-20 (from Textest AG).

Procedure: Each sample of nonwoven fabric is placed (using the appropriate clamp holder provided in the equipment) as an obstacle to air flow. Due to hydraulic losses, a difference in pressure Δp occurs (between the top and bottom sides of the nonwoven sample). The difference in pressure is recorded using a pressure gauge. The standard assessment (according to EN ISO 9237:1995) is carried out under the following conditions: clamping area 20 cm ² , pressure difference 200 Pa. The measured value can be expressed as air flow rate in liters per square meters per second (l/m ² /s).

Examples

Example 1:

In fig. 5-8 clearly illustrate an example of a disposable diaper, typically designated 20, in accordance with the present invention.

As clearly shown in FIG. 5-7, the diaper 20 is defined by a front waist region 22, a back waist region 24, an intermediate region 26 located between and connecting the front and back waist regions 22 and 24, two opposing side edges 28, an inner surface 30, and outer surface 32. The front waist region 22 includes a portion of the diaper 20 that, when worn, is located in front of the wearer, while the rear waist region 24 includes a portion of the diaper 20 that, when worn, is positioned behind the user. The intermediate region 26 of the diaper 20 includes a portion of the diaper 20 that, when worn, is located between the user's legs and covers the user's lower torso.

The diaper 20 includes an outer cover 34, an absorbent core 36, and a retention system 50. The absorbent core 36 is configured to retain and/or absorb body exudates released by the user. At the same time, the outer cover 34 and the retention system 50 are designed to hold the diaper 20 at the user's waist, hide the absorbent body 36 from view, and give the article the appearance of clothing. The diaper 20 may also include leg elastics 96 and 98 and retention flaps 100 and 102. It should be understood that depending on the intended use of the diaper 20, individual components of the diaper 20 may be optional.

In fig. 5-8 illustrate that the opposing side edges 28 of the diaper 20 are typically defined by the side edges of the outer cover 34, which further define leg openings that may be curved. The waistband edges of the outer cover 34 also define a waist opening that is configured to encircle the user's waist when worn.

In fig. 5-8 clearly show that the absorbent body 36 of the diaper 20 is suitably coupled to the outer cover 34 to form a disposable diaper 20. The absorbent body 36 can be attached to the outer cover 34 by methods known to those skilled in the art. For example, absorbent core 36 may be bonded to outer cover 34 using adhesive, thermal, or ultrasonic bonding techniques known to those skilled in the art. Alternatively, the absorbent body 36 may be connected to the outer cover 34 using conventional fasteners such as buttons, Velcro, adhesive fasteners, and the like. Other components of the diaper 20 may be suitably connected to each other in similar ways.

It is desirable for the absorbent body 36 to be coupled to the outer cover 34 only at or adjacent to the waist edges of the outer cover 34, thereby creating a front attached portion, a rear attached portion, and a loose portion that extends between and connects the attached portions. The unattached portion of the absorbent body 36 remains substantially unattached to the outer cover 34 and is typically configured to fit between the user's legs and at least partially cover the user's lower torso during use. As a result, the loose portion is typically a portion of the absorbent body 36 that is configured to initially receive body exudates of the user during use.

Thus, the absorbent core 36 is coupled to the outer cover 34 in a manner that secures the core 36 in place without adversely restricting the movement of the outer cover 34 during use. Alternatively, the absorbent body 36 may be attached to the outer cover 34 along the entire longitudinal length of the absorbent body 36 or any portion thereof, or only along the outer periphery of the absorbent body 36.

In fig. 5-8 illustrate that the absorbent body 36 of the present invention may include a backsheet 38, a topsheet 40 that is overlapped to the backsheet 38, and an absorbent core 42 that is positioned between the topsheet 40 and the backsheet 38.

The absorbent body 36 is generally comfortable and capable of absorbing and retaining body exudates. The absorbent body 36 can have any of a variety of shapes and sizes. For example, as shown in FIG. 5-8, the absorbent body 36 may be rectangular, I-shaped, or T-shaped. The size and absorbent capacity of the absorbent body 36 must be compatible with the size of the intended wearer and the fluid load generated by the intended use of the diaper 20.

The top sheet 40 of the absorbent body 36, as shown in FIG. 5-8, respectively, is a body-facing surface that is designed to be worn in close proximity to the user's body and is easily deformable, soft to the touch, and non-irritating to the user's skin.

In addition, the top sheet 40 may be less hydrophilic than the absorbent core 42 to provide the user with a relatively dry surface, and may be porous enough to be liquid permeable, allowing liquid to easily penetrate through it. A suitable topsheet 40 can be made from a wide variety of web materials, such as cellular foams, reticulated foams, perforated polymer films, natural fibers (eg, wood or cotton fibers), synthetic fibers (eg, polyester or polypropylene fibers), or combinations of natural fibers. and synthetic fibers. The top sheet 40 is suitably used to help prevent the user's skin from coming into contact with liquids retained in the absorbent core 42 of the absorbent body 36.

The top sheet 40 and the bottom sheet 38 are typically adhered to each other to form a pocket in which the absorbent core 42 is located, providing an absorbent body 36. The top sheet 40 and the bottom sheet 38 can be adhered directly to each other along the outer periphery of the absorbent core 36 by any by methods known to those skilled in the art, such as adhesive, ultrasonic or thermal bonding methods. For example, a uniform continuous layer of adhesive, a patterned layer of adhesive, a spray or melt blown pattern of adhesive, or a series of lines, swirls, or dots of adhesive may be used to attach the top sheet 40 to the bottom sheet 38. It should be noted that both the top sheet 40 and the back sheet 38 should not extend completely beyond the outer boundaries of the absorbent body 36. For example, the back sheet 38 may extend to the outer boundary of the absorbent body 36, while the top sheet 40 may be attached to backsheet 38 within the outer periphery of the absorbent body 36, or more towards the longitudinal centerline of the diaper 20.

The absorbent core 42, as clearly shown in FIG. 5-8 is located between the top sheet 40 and the bottom sheet 38 to form an absorbent core 36. It is desirable that the absorbent core 42 be easily deformable and capable of absorbing and retaining body exudates. The absorbent core 42 can take any of a variety of shapes and is typically a discrete layer within a matrix of hydrophilic fibers. Alternatively, absorbent core 42 may include a laminate of fibrous webs and highly absorbent material or other suitable means for maintaining the highly absorbent material in a localized area.

In fig. 5-8 illustrate that the absorbent body 36 of the disposable diaper 20 may include a pair of retention flaps 100 and 102 configured to provide a barrier to the lateral flow of body exudates. Retaining flaps 100 and 102 may be located along opposing side edges of the absorbent body 36. Each retaining flap defines an attached edge 104 and an unattached edge 106. Each of the containment flaps 100 and 102 may also include at least one elongate elastic member 108 adhered to the unattached edge 106 of the retaining flap 100 and 102, and be configured to facilitate the unattached edge 106 to gather and form a sealing layer against the user's body during wear. The containment flaps 100 and 102 may extend longitudinally along the entire length of the absorbent body 36 or may extend partially along the length of the absorbent body 36. If the length of the containment flaps 100 and 102 is shorter than the length of the absorbent body 36, the containment flaps 100 and 102 can be selectively located at any location along the side edges 38 of the absorbent body 36. In a particular aspect of the present disclosure, retention flaps 100 and 102 extend along the entire length of the absorbent body 36 to better retain body exudates.

Each retention valve 100 and 102 is attached to the side edges 38 of the absorbent body 36 such that the retention valves 100 and 102 provide a barrier to lateral flow of body exudates. The attached edge 104 of each of the retention flaps 100 and 102 is connected to the side edges 38 of the absorbent body 36, while the unattached edge 106 remains unconnected to the absorbent body 36 at least in the intermediate region 26 of the diaper 20. The attached edge 104 of the retention flaps 100 and 102 may be connected to the absorbent body 36 in any of several ways that are well known to those skilled in the art. For example, the attached edge 104 of the flaps 100 and 102 may be attached to the absorbent body 36 by ultrasonic, thermal, or adhesive attachment. In a particular aspect, the unattached edge 106 of each of the retention flaps 100 and 102 r remains disconnected from the side edges 38 of the absorbent body 36 along substantially the entire length of the unattached edge 106 to provide improved efficiency.

Alternatively, as shown in FIG. 4-7, the retaining flaps 100 and 102 may be integral with the bottom sheet 38 or the top sheet 40 of the absorbent body 36.

In addition, the configuration of each retention flap 100 and 102 is such that the unattached edge 106 of the retention flaps 100 and 102 is worn. tends to be positioned some distance from the absorbent body 36, typically in a vertical and perpendicular direction, especially in the intermediate region 26. In FIG. 5-8 clearly show that the unattached edge 106 of each retention flap 100 and 102 is desirably positioned at some distance from the absorbent body 36 during wear, forming a barrier to the lateral flow of body exudates. It is desirable for the unattached edge 106 of each retention flap 100 and 102 to be in contact with the user's body, while the absorbent body 36 may be positioned some distance from the user's body during wear. Typically, the elastic component 108 is coupled to the loose edge 106 of each retention flap 100 and 102 to maintain a certain distance between the loose edge 106 and the absorbent body 36. For example, the elastic component 108 may be coupled to the loose edge 106 in an elastically compressed state such that the compression elastic member 108 causes the unattached edge 106 of the retaining flap 100 and 102 to assemble, or compress and shorten.

The disposable diaper 20 in various aspects of the present disclosure may also include elastic components on the waist edges and side edges 28 of the diaper 20 to further prevent leakage of body exudates and support the absorbent body 36. For example, as illustrated in FIG. 5-8, the diaper 20 of the present invention may include two elastic leg components 96 and 98 attached to opposite side edges 28 in the intermediate region 26 of the diaper 20. The elastic leg components 96 and 98 are generally adapted to conform to the user's feet when in use, to maintain good contact with the user, so as to effectively reduce or eliminate the leakage of body exudates from the diaper 20.

The absorbent article shown in FIG. 9 according to FIG. 12 represents training pants in general form. Absorbent article 10. The longitudinal direction 48 generally extends from the front of the absorbent article to the rear of the absorbent article. The longitudinal direction 48 is opposed by the transverse direction 49. The absorbent article 10 includes a body 12, which consists of a front portion 22, a back portion 24, and an intermediate portion 26. The intermediate portion 26 contains and extends from the front portion 22 to the rear portion 24 an absorbent core 28 .

The absorbent article 10 defines an inner surface that is configured to be placed in close proximity to the body during wear. The absorbent article 10 also includes an outer surface opposite the inner surface. The front and back portions 22 and 24 represent those portions of the product that, when worn, partially cover or encircle the waist or mid-lower torso of the wearer. On the other hand, the intermediate portion 26 is typically located between the user's legs when the absorbent article is worn.

In fig. 9 shows that the absorbent article also includes a first side region 30 and a second side region 34. Side regions 30 and 34 connect the front portion 22 to the back portion 24. The side regions 30 and 34 may also help define leg openings and waist openings.

The side regions 30 and 34 in one embodiment may be made of stretchable or extendable material. In one embodiment, the side regions 30 and 34 are made of elastic material. These side areas provide a tight but comfortable fit to the user's body. The side regions 30 and 34 are also adaptable to different torso sizes.

It is shown that each of the side regions 30 and 34 can be made from a plurality of stretch panels. For example, in the embodiment shown in FIG. 9, each of the side areas 30 and 34 is made of two panels. For example, side region 30 is shown to include a first panel 31 and a second panel 33. Likewise, second side region 34 includes a first panel 35 attached to a second panel 37. Panels 31 and 33 of the first side region 30 are fastened together. forming a first vertical joint area 41, while panels 35 and 37 of the second side region 34 are connected to each other along a second vertical joint area 43. The connection between the panels may be permanent or may be non-release and re-fastenable. If the panels are releasably connected to each other, for example, any suitable mechanical fastening may be used. For example, in one embodiment, the panels may be releasably connected to each other using any suitable adhesive fastening, cohesive fastening, mechanical fastening, or the like. Suitable mechanical fasteners may be made of geometrically shaped interlocking materials such as hooks, loops, pear-shaped, mushroom-shaped, arrow-shaped, ball-on-rod, male and female components, buckles, latches, and the like.

In the embodiment shown in FIG. 9-12, panels 31 and 33 including first side region 30, and panels 35 and 37 including second side region 34 are fastened together by a fastening system 80 that includes lateral opposing first fastening components 82 adapted to be fastening to corresponding second fastening components 84. For example, in one embodiment, the outer and inner surface of each of the fastening components 82, 84 includes a plurality of fastening elements. The fastening elements of the first fastening components 82 are adapted to repeatedly attach and disengage corresponding fastening elements of the second fastening components 84 to secure the absorbent article in its three-dimensional releasably configuration.

For example, in one embodiment, the first fastening components 82 include loop fasteners and the second fastening components 84 include compatible hook fasteners. Alternatively, the first fastening components 82 may include hook fasteners and the second fastening components 84 may include corresponding loop fasteners. In another aspect, the fastener components 82 and 84 may be interlocking same-surface fasteners, or adhesive or coadhesive fasteners, such as adhesive fasteners and the adhesive fastener receiving area and material.

As described above in an alternative embodiment, the panels comprising the side regions may be permanently secured to each other. For example, in FIG. 10 illustrates an alternative embodiment of an absorbent article 10. Like reference numerals have been used to denote the same or similar elements. It is shown that the absorbent article 10 in FIG. 10 includes a first side region 30 containing panels 31 and 33, and a second side region 34 containing panels 35 and 37. First side panel 30 defines a first vertical joint region 41 in which panels 31 and 33 are permanently secured to each other. . Likewise, the second side region 34 defines a second vertical connection region 43 in which the panels 35 and 37 are permanently secured to each other. In this embodiment, the vertical connection areas include seams. For example, the seams can be arranged in any suitable manner. For example, a vertical seam may include a lap seam, a butt seam, or any other suitable configuration. Seams can be obtained by fastening the panels together by any suitable method or method. For example, the panels can be permanently bonded together by ultrasonic, thermal, adhesive and/or pressure bonding. In yet another alternative embodiment, the individual panels can be sewn together.

As shown in FIG. 9 and 10, when the side regions 30 and 34 are in the fastened position, the front and back portions 22 and 24 are connected to each other to form a pant of a 3-dimensional configuration having a waist hole 50 and two leg holes 52. While wearing the absorbent of the article 10, the side regions 30 and 34 thus include portions of the article located at the user's hips and, in one embodiment, define the upper edge of the leg openings 52.

As described above, the base 12 may, in one embodiment, include an outer layer 40 and a top sheet 42, as shown particularly in FIG. 11 and 12. Depending on the embodiment, the outer layer 40 and the top sheet 42 may consist of a single piece of material or may consist of several pieces of material joined together. The top sheet 42 may be attached to the outer layer 40 by application using, for example, adhesives, ultrasonic welding, heat sealing, pressure bonding, or other standard methods. The top sheet 42 may be suitably attached to the outer layer 40 along the perimeter of the base 12 to form a front waist seam 62 and a rear waist seam 64. The top sheet 42 may also be attached to the outer layer 40 to form two side seams 61. The top sheet 42 may be generally adapted, that is, positioned relative to other components of the absorbent article 10 so as to face the user's skin when worn. As described above, the base 12 also includes an absorbent core 28 positioned between the outer layer 40 and the top sheet 42 for absorbing body fluids excreted by the user.

According to the present disclosure, the absorbent article 10 also includes one or more elongated waistbands designed to enhance the appearance of the product, to improve the fit, and/or to make the product more like actual undergarments. As shown in the figures, for example, absorbent article 10 may include a back waistband 56, a front waistband 54, or may include both a front waistband and a back waistband. For example, the back band 56 is shown to extend across the entire rear portion 24 of the base 12 and terminate at each end of the side edges 30 and 34.

It is intended that the present disclosure is not limited to any previously described embodiment, and that certain modifications may be added to the manufacturing example presented without departing from the appended claims. For example, although the above example refers to the embodiments shown in FIGS. 5 according to FIG. 8, similar structures may be present in other embodiments as shown in FIG. 9 according to FIG. 12, and other feminine hygiene items, for example, such as those shown in FIG. 13 and fig. 14. Additionally, while the examples and figures relate to diapers and pant diapers for infants, they are also applicable to incontinence diapers and panties for adults, albeit with some structural changes that will be obvious to one skilled in the art. technology.

Example 2:

Regarding FIG. 13 and fig. 14, the absorbent articles may be sanitary napkin or sanitary napkin type articles.

The structure of the napkin or pad may vary in design if the core described in the present invention is used. Typically, such a napkin or pad comprises a laminate including a backsheet, an absorbent core (with or without three-dimensional absorbent material), and an optional liquid distribution layer (ADL) located between the topsheet and the absorbent core.

In fig. 14 shows that the interconnected channel 106 may be plural and present substantially concentric circles with respect to each other, and may be inversely shaped with respect to an axis parallel to the width of the core. Although such a pattern is provided as an example for use in a core for a sanitary napkin or pad 300, a similar pattern can also be used and is included in the teaching provided in the disclosure for diaper and panty cores (whether intended for infants or incontinent adults).

Example 3:

Reference - Commercially available infant diapers (junior size) containing a channel-free core containing a mixture of fluff fibers and SAP (sold by Ontex bvba under the name FlexFit) are tested according to the method described above to determine "dose time". A total of 5 diaper samples are tested, each having an acquisition distribution layer (ADL) corresponding to sample A-C described below. The mean reception time and standard deviation (STD) values are presented in Table 1 below.

Sample A – 50 ^gsm basis weight air bonded nonwoven layer (commercially available from TWE Meulebeke bvba and sold under the name DryWeb T28)

Sample B is a layer of spunbond nonwoven fabric containing 100% polypropylene (PP) fibers and having a basis weight of 21 g/ ^m2 (commercially available from Fitesa Italy Srl. and sold under article code ISEW-100 021 FA-S )

Sample C is a layer of carded thermally bonded nonwoven containing 100% polypropylene (PP) fibers and having a basis weight of 30 g/ ^m2 (commercially available from Union Industries SpA and sold under item code T3000PIWT)

Table 1:

Example 3 Average reception time (s) STD for reception time (s) Sample A 106 12 Sample B 346 103 Sample C 262 60

From the results presented in Table 1, it can be seen that for traditional channelless diapers, the average take-up time is very long when using ADL according to samples B and C. Values above 200 are considered unacceptable in the industry (e.g. Hy-Tec target values for baby diapers 01-2019), while values below 200 are considered acceptable (especially for sizes junior/junior+, maxi/maxi+, XL/XL+). In the latter case, the use of such ADLs in modern diapers was abandoned.

Example 4:

Baby diapers (junior size) with a core including a single U-shaped channel, containing no absorbent material therein, comprising a mixture of fluff fibers and SAP, are tested according to the method described above for the method of determining “dose time”. A total of 5 diaper samples are tested, each having an acquisition distribution layer (ADL) corresponding to sample A'-C' described below. The mean reception time and standard deviation (STD) values are presented in Table 2 below.

Sample A' – layer of air bonded nonwoven fabric with a basis weight of 50 g/ ^m2 (commercially available from TWE Meulebeke bvba and sold under the name DryWeb T28)

Sample B' is a layer of spunbond nonwoven material containing 100% polypropylene (PP) fibers and having a basis weight of 21 g/ ^m2 (commercially available from Fitesa Italy Srl. and sold under article code ISEW-100 021 FA- S)

Sample C' - a layer of carded thermally bonded nonwoven containing 100% polypropylene (PP) fibers and having a basis weight of 30 g/ ^m2 (commercially available from Union Industries SpA and sold under article code T3000PIWT)

Table 2:

Example 4 Average reception time (s) STD for reception time (s) Sample A' 19 3 Sample B' 47 9 Sample C' 36 2

From the results of Table 2, it is clear that the introduction of a channel-containing core allows for a significant reduction in dosing time, with ADLs according to Samples B' and C' providing very acceptable performance (especially according to the Hy-Tec thresholds discussed in Example 3).

Example 5:

Control - Commercially available baby diapers (junior size) with a channel-free core comprising a mixture of fluff fibers and SAP (sold by Ontex bvba under the name FlexFit) are tested according to the method described above for the "surface dryness (rewetting)" method. A total of 6 sample diapers are tested, each having an acquisition distribution layer (ADL) corresponding to sample A-C described below. The mean absorption time and standard deviation (STD) values are presented in Table 3 below.

Sample A – 50 ^gsm basis weight air bonded nonwoven layer (commercially available from TWE Meulebeke bvba and sold under the name DryWeb T28)

Sample B is a layer of spunbond nonwoven fabric containing 100% polypropylene (PP) fibers and having a basis weight of 21 g/ ^m2 (commercially available from Fitesa Italy Srl. and sold under article code ISEW-100 021 FA-S )

Sample C is a layer of carded thermally bonded nonwoven containing 100% polypropylene (PP) fibers and having a basis weight of 30 g/ ^m2 (commercially available from Union Industries SpA and sold under item code T3000PIWT)

Table 3:

Example 5 Average rewetting (g) STD for re-wetting (g) Sample A 0.22 0.03 Sample B 0.03 0.01 Sample C 0.02 0.01

The results shown in Table 3 demonstrate lower rewetting efficiency of diapers containing Sample A ADL.

Example 6:

Baby diapers (junior size) with a core comprising a single U-shaped channel containing no absorbent material therein comprising a mixture of fluff fibers and SAP are tested according to the method described above for determining "surface dryness (rewetting)". A total of 6 diaper samples are tested, each having an acquisition distribution layer (ADL) corresponding to sample A'-C' described below. The mean absorption time and standard deviation (STD) values are presented in Table 4 below.

Sample A' – layer of air bonded nonwoven fabric with a basis weight of 50 g/ ^m2 (commercially available from TWE Meulebeke bvba and sold under the name DryWeb T28)

Sample B' is a layer of spunbond nonwoven material containing 100% polypropylene (PP) fibers and having a basis weight of 21 g/ ^m2 (commercially available from Fitesa Italy Srl. and sold under article code ISEW-100 021 FA- S)

Sample C' - a layer of carded thermally bonded nonwoven containing 100% polypropylene (PP) fibers and having a basis weight of 30 g/ ^m2 (commercially available from Union Industries SpA and sold under article code T3000PIWT)

Table 4:

Example 6 Average rewetting (g) STD for re-wetting (g) Sample A' 0.12 0.02 Sample B' 0.03 0.01 Sample C' 0.03 0.01

From the results presented, it can be seen that when ADL is introduced according to patterns B/B' and C/C' into diapers with channel cores, an optimal balance of absorption time (example 4) and rewetting time (example 6) is unexpectedly achieved. The trade-off in absorption time efficiency for channel-containing diapers (Example 4) when selecting samples B/B' and C/C' is much lower compared to non-channel diapers (Example 3), with this trade-off being significantly outweighed by the significant improvement in rewetting to maintain superior perceived dryness. This results in cost-optimal overall performance of the diaper.

Example 7:

ADL according to samples A/A', B/B', C/C' of Examples 3 to 6 are further tested according to the bulk density determination method described above, and the results are presented in Table 5.

Table 5:

Sample Bulk density (g/cm ³ ) Specific volume (cm ³ /g) A/A' 0.087 11.43 B/B' 0.100 10.03 C/C' 0.089 11.17

Example 8:

The ADLs according to Samples A/A', B/B', C/C' of Examples 3 to 6 are further tested for moisture retention. This test includes the following steps: cutting each sample into 245 mm x 80 mm pieces, measuring and recording the dry weight of the sample, immersing each sample in a reservoir of saline solution (similar to the solution described/used in examples 3 to 6 ) and leaving it in the solution for 2 minutes, removing the sample from the reservoir and leaving it to drain excess liquid, fixing one end of the sample with a cantilever clamp, and leaving it hanging by gravity at room conditions for 3 minutes; then re-measure the mass. The difference in mass between the dry condition and the wet test condition gives the mass of liquid retained. This test is repeated at least 3 times for each of the samples. A/A', B/B', C/C' from examples 3 to 6. The results are presented in table 6.

Table 6:

Sample Moisture retention (g) STD(g) A/A' 12.4 1.0 B/B' 3.1 0.1 C/C' 4.7 1.0

From the results presented in Table 6, it can be seen that the ADL according to sample A/A' retains significantly more liquid compared to samples B/B' and C/C'. Without wishing to be bound by theory, it is believed that one reason for the more effectively perceived dryness is due to the sponge effect exerted by the ADL.

Example 9:

Diapers according to examples 3 to 6, containing ADL according to pattern A/A' and B/B', were tested for visual control of residual moisture. This parameter is determined using the following method: pour 150 ml of tap water at a time into a diaper placed in a bowl on a table, record the waiting time and allow the liquid to be absorbed by the diaper for a waiting period of 90 seconds, cover with a softshell cloth (water-repellent hydrophobic fabric , 100% polyester) top sheet on the skin-facing side of the diaper and apply a 4 kg weight for 5 seconds, remove the softshell fabric and visually check whether there are traces of moisture on it. In fig. 23 shows the difference in the appearance of the resulting wetness, with the diaper containing Sample A/A' ADL exhibiting a significantly higher degree of residual moisture compared to the same diaper containing Sample B/B' ADL.

Example 10:

ADL according to samples A/A', B/B', C/C' are tested for relative porosity according to the air permeability testing method described in the disclosure.

Three identical samples of each of samples A/A', B/B', C/C' are cut and trimmed to a size corresponding to a clamping area of 20 cm ² as described in the test method described in the disclosure (and in accordance with ISO 9237:1995 ), calculate the average relative porosity and the corresponding standard deviation (STD) and present the results in Table 7.

Table7:

Sample Relative porosity (l/ ^m2 /s) STD (l/ ^m2 /s) A/A' 9027 17 B/B' 4043 83 C/C' 4433 295

The results presented in Table 7 demonstrate significantly higher relative porosity values for sample A/A' compared to samples B/B' and C/C'. Without wishing to be bound by theory, higher relative porosity values promote capillary action to such an extent that during use it results in a sponge effect affecting the perception of moisture after the release of exudates.

Claims (15)

1. An absorbent article (10, 20, 300, 500, 600) comprising an absorbent core (101, 501, 601) located between a liquid-permeable top sheet (520, 620) and a liquid-impervious back sheet (521, 621) , and a receiving distribution layer (522, 622) located between said top sheet (520, 620) and said absorbent core (101, 501, 601), wherein the absorbent core (101, 501, 601) contains an absorbent material selected from the group consisting of cellulose fibers, superabsorbent polymers and combinations thereof, wherein said absorbent core (101, 501, 601) comprises at least one interconnected channel (106) free of said absorbent material, said channel (106) having a length extending along the longitudinal axis (48), and the absorbent core (101, 501, 601) has a length extending along the specified longitudinal axis (48), and the length of the specified channel (106) is from 10% to 95% of the length of the specified absorbent core ( 101, 501, 601), characterized in that the receiving distribution layer (522, 622) contains a layer of spunbond and/or carded nonwoven material, including synthetic fibers, and said synthetic fibers are contained in an amount greater than 80 wt.% relative to the weight of the specified an acquisition distribution layer (522, 622), wherein said acquisition distribution layer (522, 622) has a basis weight of from 18 to 40 ^gsm , wherein the acquisition distribution layer (522, 622) is located on the body facing side of the absorbent core (101, 501, 601) and in direct contact with the body facing side of the absorbent core (101, 501, 601). 2. The absorbent article according to claim 1, wherein the absorbent core (101, 501, 601) contains one interconnected channel (106). 3. Absorbent product according to any one of paragraphs. 1 or 2, wherein the interconnected channel (106) extends both along a longitudinal axis (48) and along an axis perpendicular to said longitudinal axis (48) to form a substantially U-shaped shape. 4. Absorbent product according to any one of paragraphs. 1-3, wherein the receiving distribution layer (522, 622) has a specific volume of less than 11.4 cm ³ /g, preferably less than 11.3 cm ³ /g, more preferably from 5.5 cm ³ /g to 11.2 cm ³ /g, even more preferably from 8.5 cm ³ /g to 11.17 cm ³ /g. 5. Absorbent product according to any one of paragraphs. 1-4, in which the synthetic fibers are contained in an amount of more than 90 wt.%, preferably from 95 wt.% to 100 wt.% relative to the weight of the specified receiving distribution layer (522, 622). 6. Absorbent product according to any one of paragraphs. 1-5, wherein the receiving distribution layer (522, 622) consists of synthetic fibers and preferably does not contain cellulose fibers, more preferably said receiving distribution layer (522, 622) is subject to treatment, for example with a surfactant, to impart the specified layer (522, 622) of hydrophilic properties. 7. Absorbent product according to any one of paragraphs. 1-6, in which synthetic fibers contain, preferably consist of polypropylene fibers. 8. Absorbent product according to any one of paragraphs. 1-7, wherein the receiving distribution layer (522, 622) is preferably a single layer of spunbond or carded nonwoven material and is devoid of layers of through-air bonded, dry air-spun, and/or meltblown nonwoven materials. 9. Absorbent product according to any one of paragraphs. 1-8, wherein the acquisition distribution layer (522, 622) has a basis weight of 18 to 35 ^gsm , preferably 20 to 30 ^gsm , preferably 21 to 25 ^gsm . 10. Absorbent product according to any one of paragraphs. 1-9, wherein the carded nonwoven layer is a layer of carded thermally bonded nonwoven material. 11. Absorbent product according to any one of paragraphs. 1-10, in which the receiving distribution layer (522, 622) has an average pore size of from 15 μm to 200 μm, preferably from 30 μm to 150 μm, more preferably from 45 μm to 130 μm, even more preferably from 55 μm to 110 μm, even more preferably from 60 μm to less than 100 μm, even more preferably from 65 μm to 95 μm, even more preferably from 70 μm to 90 μm. 12. Absorbent product according to any one of paragraphs. 1-11, wherein the acquisition distribution layer (522, 622) comprises a first center position (C _ADL ), and the absorbent core (101, 501, 601) comprises a second center position (C _c ), wherein the acquisition distribution layer (522, 622) is positioned asymmetrically relative to the absorbent core (101, 501, 601) such that the first center position (C _ADL ) and the second center position (C _c ) are offset at least along the longitudinal axis (48), preferably the receiving the distribution layer (522, 622) is positioned such that it does not block a portion of the channel (106) extending transversely along an axis substantially perpendicular to said longitudinal axis (48). 13. Absorbent product according to any one of paragraphs. 1-12, in which the receiving distribution layer (522, 622) has a relative porosity of less than 9000 l/m ² /s, preferably from 1000 l/m ² /s to 8000 l/m ² /s, preferably from 2000 l/m ² /s to 7000 l/m ² /s, more preferably from 3000 l/m ² /s to 5000 l/m ² /s, most preferably from 3500 l/m ² /s to 4500 l/m ² /s. 14. The use of a nonwoven material having a porosity of less than 9000 l/m ² /s as a receiving distribution layer (522, 622) for an absorbent article containing an absorbent core (101, 501, 601) located between a liquid-permeable top sheet (520, 620) and a liquid impermeable backsheet (521, 621), wherein said acquisition distribution layer (522, 622) is located between said topsheet (520, 620) and said absorbent core (101, 501, 601), wherein the absorbent core (101, 501, 601) contains an absorbent material selected from the group consisting of cellulose fibers, superabsorbent polymers and combinations thereof, wherein said absorbent core (101, 501, 601) contains at least one interconnected channel (106), devoid of said absorbent material, wherein said channel (106) has a length extending along the longitudinal axis (48), and the absorbent core (101, 501, 601) has a length extending along said longitudinal axis (48), with wherein the length of said channel (106) is from 10% to 95% of the length of said absorbent core (101, 501, 601), wherein the receiving distribution layer (522, 622) is located on the body-facing side of the absorbent core (101, 501, 601) and in direct contact with the body facing side of the absorbent core (101, 501, 601). 15. Use according to claim 14, in which the relative porosity is from 1000 l/m ² /s to 8000 l/m ² /s, preferably from 2000 l/m ² /s to 7000 l/m ² /s, more preferably from 3000 l/m ² /s to 5000 l/m ² /s, most preferably from 3500 l/m ² /s to 4500 l/m ² /s, preferably the absorbent product is a product according to any one of claims. 1-13.