MXPA00000040A - Body adhering disposable absorbent articles having an increased fit for the body anatomy - Google Patents

Abstract

A tridimensional disposable absorbent article having a body facing surface and a garment facing surface, a longitudinal symmetry plane, a front end edge and a rear end edge, and comprising a liquid pervious topsheet, a backsheet joined to said topsheet and an absorbent core intermediate the backsheet and the topsheet. The absorbent core has a front portion, a central portion and a rear portion, and comprises a longitudinally oriented ridge in the central and rear portion having a profile that provides for an increased body fit. The article is intended for direct attachment to the skin of the wearer and comprises an adhesive on the body facing surface.

Description

DISPOSABLE ABSORBING ITEMS ADHERING TO THE BODY THAT HAVE AN ADJUSTMENT INCREASED BY ANATOMY FROM THE USER FIELD OF THE INVENTION The present invention relates to disposable absorbent articles. Disposable absorbent articles are considered as absorbent devices designed to be used externally of the body by a user and to receive fluids discharged from the body. In particular, the present invention relates to disposable absorbent sanitary napkins, menstruation pads, incontinence inserts, and panty liners that are capable of providing improved fit for the body and reduced drip by equalizing non-planar surfaces and non-linear grooves. of the body. Disposable absorbent articles comprise an absorbent core having a front portion, a central portion and a rear portion, and comprise a seam oriented longitudinally in the central and rear portions having a slope that slopes backward. The disposable absorbent articles are intended for direct attachment to the user's skin and comprise an adhesive on the surface facing the body.

BACKGROUND OF THE INVENTION In its basic form, disposable absorbent articles comprise an absorbent core interposed between a permeable element that contacts the body (alternatively referred to as a backsheet). Of course, the absorbent element must receive and contain the fluids discharged from the body. The element that makes contact with the body must provide comfortable contact and dry feeling with the body surfaces, while allowing free passage of fluids in the absorbent element. The lining barrier must prevent fluids, which are expelled or escaping from the absorbent element, from soiling the user's garment. The major disadvantages of known absorbent articles to be used externally of the body, eg, dripping, wet / dirty feeling, discomfort, refer to the poor fit to the body achieved by these articles which are substantially flat before being used and then must be squeezed or bend in the correct way to follow the surface of the body or, alternatively, they are molded before use, but anyway they need to improve in order to obtain a better fit with the complex shapes of the user's anatomy. In addition, most known disposable absorbent articles should be applied to the panty, and are typically fixed with an adhesive, and this does not facilitate a good fit with the anatomy of the body, also due to differences in usage habits and styles. of panties. With respect to disposable sanitary napkins, several attempts have been made in the art to improve body contact with the wearer, and thus absorb fluids when unloading and minimize dirt, by means of a sanitary napkin having an anatomically shaped configuration with the ability to adapt to the anatomy of the body.

In female users, this type of sanitary napkin tries to make contact with and absorb menstruation immediately as it leaves the lobby. Sanitary napkins that conform to the body are known in the art, both those that are flat before use and that must be adapted and molded during use to match the anatomy of the wearer, and those that are adapted before use. In the European patent application EP 971 1 0735.4, filed on July 1, 1 997, disposable absorbent articles, in particular sanitary napkins, have been described, which are provided before being used with an improved three-dimensional structure capable of adapting to the different shapes complex female body anatomy comprising non-linear grooves and non-planar surfaces, in order to provide improved fit to the body and comfort, and reduced drip. Said disposable absorbent articles comprise a seam oriented longitudinally in the central and rear portions with a declivity that slopes backwards, and preferably they should be for direct application to the user's body. The three-dimensional items in accordance with EP 971 10735.4 are able to adapt so close to the anatomy of the body that they are very comfortable for the user and provide a good fit upon use provided they remain in place during the time of use. So far they can be improved in that they remain in place during their use. Due to their particular structure, these articles are in fact able to achieve a much closer contact with the body of the user, in comparison with the flat products and formed in a known three-dimensional way, and since preferably they should be for direct application to the body of the user, can improve by incorporating on its surface that faces the body of an adhesive for fixing topical adhesive to the body of the user in the area where body fluid absorption is desired. The use of traditional means to secure the article to the underwear, although possible in this type of three-dimensional articles, in fact, does not particularly support the benefits of the particular close fitting product during use, since even small relative movements between the garment and the body that are unavoidable during the time of use will affect the product and will tend to move it, at least to some degree, from its preferred position in close contact with the anatomy. In addition, this effect will also be influenced by the style of the panties and the habits of the user. Therefore, the incorporation of an adhesive to the body on the body-facing surface of a three-dimensional article in accordance with EP 971 1 0735.4 is advantageous in particular, since it provides an article having an improved ability to adjust and conform to the anatomy, with firm and stable contact with the user's body. In addition, the best fit and comfort of these three-dimensional items by themselves are able to improve the effectiveness of any known body adhesive incorporated in the article, since in the direct application to the body, these articles can be adjusted much more efficiently in the position correct in comparison with known three-dimensional items, thus minimizing the possibility of the article adhering to the body in an incorrect position.

At the same time, the adjustment very close to the body that can be achieved by this type of three-dimensional items makes the articles adjust in the same way every time, substantially with any user, and therefore, the location of an acquisition zone in the article it is much more predictable compared to known products, where an acquisition point can not be precisely defined. This allows the placement of a body adhesive on a larger portion of the surface facing the body of the article, or in any case at most suitable locations in order to make the article stay in place when used, thus achieving better contact with the user's body without interfering with the absorption and acquisition properties of the article. Body adhesive compositions such as those described in the European patent application EP 971 1 0727.1 can be advantageously used in combination with the three-dimensional disposable absorbent articles, since they provide painless removal of the absorbent articles, without residue of adhesive in the body of the user. Even more preferable, the advantages for body adhesives described in the European patent application EP 971 10730.5 can be used in the context of the present invention. Therefore, an object of the present invention is to provide disposable three-dimensional absorbent articles, in particular sanitary napkins, having a structure capable of conforming to the different complex shapes of the female anatomy body comprising non-linear grooves and non-planar surfaces, which must be for direct application to the body of the user, and are fixed to the skin of the user by means of a body adhesive composition applied to the surface facing the body of the article, preferably without causing discomfort to the user during the application and in particular during the removal of the absorbent article. Another object of the present invention is to provide a three-dimensional disposable absorbent article that can be more easily adhered in the correct position in the wearer's body. Another object of the present invention is to provide three-dimensional disposable absorbent articles that are used in such close proximity to the wearer's area that emanates liquid that they are minimized or losses of liquid are eliminated outside of the absorbent area. For disposable absorbent articles used in the crotch area of a wearer, this would result in improved security against dirt from the surrounding skin tissue and clothing. Still another object of the present invention is to provide a three-dimensional disposable absorbent article that is affixed to the wearer's skin by means of a body adhesive that provides painless removal of the absorbent article and no residue of adhesive on the wearer's body upon removal.

BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a three-dimensional disposable absorbent article having a body-facing surface and a garment-facing surface, a plane of longitudinal symmetry, a front end edge and a trailing end edge, which it comprises a liquid permeable top sheet, a back sheet attached to the top sheet and an intermediate absorbent core between the top sheet and the back sheet, the absorbent core comprising a front portion, a central portion and a back portion. The surface that faces the body defines a line formed by the intersection of the surface that looks at the body with the plane of symmetry, the line being present in a system of the Cartesian plane x and within the plane of symmetry, with the x axis defined by the two points of intersection of the plane of longitudinal symmetry with the front end edge and the rear end edge, and with the surface facing the body facing positive values and, the line with a first derivative with respect to said Cartesian system xy. The article is such that at least one value of the first derivative of the line in the central portion of the absorbent core is greater than at least one value of the first derivative of the line in the rear portion of the absorbent core. The article further comprises in at least part of the body facing surface an adhesive for fixing topical adhesive to a user of the article.

BRIEF DESCRIPTION OF THE DRAWINGS Although the specification concludes with claims that point in particular and distinctly claim the present invention, it is believed that the present invention will be better understood from the following description along with the following drawings: Figure 1 is a perspective view of a modality of a sanitary napkin according to the present invention; Figure 2 is a cross-sectional view of the sanitary napkin of Figure 1 on line 2-2; Figure 3 is a top view of the sanitary napkin of Figure 1; Figure 4 is a curve taken from an anatomical section of the body of a user, schematically representing the central non-linear groove of the female anatomy as seen in the lateral direction; Figures 5a, 5b and 5c are cross-sectional views of the sanitary napkin of Figure 1 on lines 5a-5a, 5b-5b and 5c-5c, respectively. Figure 6 is a perspective view of an alternative embodiment of a sanitary napkin according to the present invention, seen from the side that is away from the user in use.

DETAILED DESCRIPTION OF THE INVENTION This invention relates to three-dimensional disposable absorbent articles that exhibit absorption for body fluids, protection of the user's garments from soiling, and improved physical comfort for the user, which are also easy to produce and pack and which they exhibit improved fit to the body and better adaptation to the user's anatomy by providing a three-dimensional structure capable of equalizing the non-linear grooves and non-planar surfaces of the female body. The articles are applied directly to the skin of a user. Disposable absorbent articles are described below with reference to a sanitary napkin or menstruation pad. The term "sanitary napkin", as used herein, refers to an article that women use externally of the body and adjacent to the pudendal region and that must absorb and contain various body fluids that are discharged from the body (eg, example, vaginal discharges, menstruation and / or urine) and that should be discarded after a single use. However, it should be understood that the present invention is also applicable to other feminine hygiene or menstruation products such as panty liners, or other absorbent articles such as incontinence pads, and the like. The term "use", as used herein, refers to the period that begins when the absorbent article actually comes into contact with the user's anatomy. The terms "attached" or "fixed", as used herein, encompass configurations by which a first member is directly connected to a second member and configurations by which a first member indirectly connects to a second member by connecting the first member to intermediate members who in turn connect to the second member. As used herein, the term "pudendo (a)" refers to the externally visible female genitalia and is limited to the labia majora, labia minora, clitoris, and vestibule. Figure 1 is a perspective view of a sanitary napkin 20 of the present invention with its three-dimensional structure before use, with most of the portion of the sanitary napkin 20 facing or contacting the user, facing towards the observer. By saying "before use", it is meant that the sanitary napkin 20 of the present invention is provided with a three-dimensional structure before it is actually used. However, the sanitary napkin can be packaged in a folded planar configuration, subsequently unfolded to obtain the three-dimensional shape just before use. As best shown in Figure 2, the sanitary napkin 20 comprises a liquid permeable upper sheet 22, a liquid impermeable back sheet 23 joined with the upper sheet 22, and an absorbent core 24 positioned between the topsheet 22 and the backsheet 23. The sanitary napkin 20 has two surfaces, a surface that faces or makes contact with the body 20a and a surface that faces or makes contact with the garment 20b. The surface contacting the body 20a should be used adjacent the user's body, while the garment surface 20b is on the opposite side and should be directed towards the underwear when the sanitary napkin 20 is used, for example, against the same. Corresponding body and garment facing surfaces can also be identified in each individual layer constituting the sanitary napkin 20, for example, in the absorbent core 24. The sanitary napkin 20 has a plane of longitudinal symmetry S. The term "longitudinal", as used herein, it refers to a line, axis or direction in the sanitary napkin 20 that is generally aligned with (eg, approximately parallel to) a vertical plane that divides a user standing in halves of the left body and right when using the sanitary napkin 20. The plane of symmetry S of the sanitary napkin 20 substantially corresponds to this vertical plane that divides the user standing up. Although it is preferred that the sanitary napkin 20 be divided exactly by the plane of longitudinal symmetry S into two symmetrically equal halves, it is not excluded that the two halves are not specular. The term "transverse", as used herein, refers to a direction that is generally perpendicular to the plane of longitudinal symmetry S. the term "longitudinally oriented" refers to a direction, as seen in Plan view, included within ± 45 degrees, of the plane of longitudinal symmetry S; the term "transversely oriented" refers similarly to any other direction, as seen in plan view. The terms "front" and "rear", as used herein, refer to portions that face the front and back of the user's body, respectively, when the sanitary napkin 20 is used. The sanitary napkin 20 has a periphery 30, which is defined by the outer edges of the sanitary napkin 20. The longitudinal edges 31 of the sanitary napkin 20 are aligned with the longitudinal symmetry plane S, and the end edges of the sanitary napkin 20 comprise a front end edge 32a and a rear end edge 32b. The absorbent core 24 of the sanitary napkin has a front portion 40, a central portion 42 and a rear portion 44, each preferably corresponding to approximately one third of the total length of the absorbent core 24. Also the front, middle and rear portions , corresponding, can be identified respectively in the sanitary napkin 20. The sanitary napkin 20 of the present invention is three-dimensional, since it is provided before being used with a three-dimensional structure that must match the complex body shapes of the female anatomy. The three-dimensional structure preferably has a structural three-dimensionality, by "structural three-dimensionality" it is meant that the structure can not be completely flattened on a flat surface while maintaining its integrity, that is, without crushing or crushing in any case. In other words, the three-dimensional structure can not be achieved by simply folding or folding an initially flat article, but it is inherently due to the absorbent article in accordance with the present invention. The three-dimensional sanitary towel 20 of the present invention preferably has a substantially constant thickness, which is more preferably less than 5 mm; therefore, the sanitary napkin can be considered the thin type. While the topsheet, backsheet and absorbent core can be assembled in a variety of well-known configurations (including so-called "tube" products or side flap products), Figure 1 shows a preferred embodiment of the sanitary napkin. wherein the topsheet 22 and the backsheet 23 have dimensions of length and width generally larger than those of the absorbent core 24. The topsheet 22 and the backsheet 23 extend beyond the edges of the absorbent core 24 to thus forming the periphery 30 of the sanitary napkin 20. The upper sheet 22 is comfortable, soft and non-irritating to the wearer's skin. In addition, the topsheet 22 is permeable to liquid, which allows the liquid (eg, menstruation and / or urine) to penetrate through its thickness. A suitable top sheet 22 can be manufactured from a wide scale of materials such as woven and nonwoven materials; polymeric materials such as open formed thermoplastic films, open plastic films, and hydroformed thermoplastic films; porous foams; cross-linked foams; crosslinked thermoplastic films; and thermoplastic fabrics. Suitable woven and nonwoven materials may be comprised of natural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g., polymer fibers such as polyester, polypropylene or polyethylene fibers); or a combination of natural and synthetic fibers. A preferred top sheet comprises an open formed film. Open-formed films for the topsheet are preferred as they are permeable to body fluids and not yet absorbent and have a reduced tendency to allow liquids to re-pass and re-wet the wearer's skin. In this way, the surface of the formed film that is in contact with the body, remains dry, thus reducing dirt from the body and creating a more comfortable feeling for the user.

Suitable formed films are described in the U.S. Patent. No. 3,929,135, issued to Thompson on December 30, 1975; Patent of E.U.A. No. 4,324,246, issued to Mullane et al. On April 13, 1982; Patent of E.U.A. No. 4,342,314, issued to Radel et al. On August 3, 1982; Patent of E.U.A. No. 4,463,045, issued to Ahr et al. On July 31, 1984; and Patent of E.U.A. No. 5,006,394, issued to Baird on April 9, 1991. A preferred top sheet for the absorbent article of the present invention is a formed film described in one or more of the above patents and marketed in sanitary napkins by The Procter & Gamble Company of Cincinnati, Ohio as "DRI-WEAVE".

The upper sheets which do not have a homogeneous distribution of liquid passage, but only a portion of the upper sheet comprising liquid passage are also contemplated by the present invention. Typically said upper sheets would have the liquid passages oriented so as to result in a centrally permeable upper sheet and peripherally impermeable to liquids. In a preferred embodiment of the present invention, the exposed body or surface of the formed top sheet of film is hydrophilic in order to aid in liquid transfer through the upper sheet faster than if the body surface were not hydrophilic, for thus decreasing the likelihood that the menstrual fluid will flow out of the upper sheet instead of flowing in and absorbed by the absorbent core. In a preferred embodiment, surfactant is incorporated into the polymeric materials of the formed film topsheet as described in the PCT application WO 93/09741. Alternatively, the body surface of the topsheet can be made hydrophilic by treating it with a surfactant such as is described in US Pat. 4,950,254.

Another alternative is the so-called hybrid upper sheets incorporating fibrous structures and the type of film structures useful in particular of said hybrid upper sheets described in the PCT applications WO 93/09744; WO 93/11725 or WO 93/11726. When referring to the top sheet, a multilayer or single layer structure is contemplated. The hybrid top sheet mentioned above is a multilayer design as such, but other multilayer top sheets such as primary and secondary top sheet designs are also considered. The absorbent core 24 may be any absorbent means that is capable of absorbing and retaining liquids (e.g., menstruation and / or urine). The absorbent core 24 can be manufactured in a wide variety of sizes and shapes (e.g., rectangular, oval, hourglass, asymmetric, etc.) and a wide variety of liquid absorbent materials commonly used in sanitary napkins and other articles. absorbers such as wood pulp which is generally referred to as air felt. Examples of other suitable absorbent materials include cellulose filler, modified intertwined cellulose fibers (such as those described in US Patent No. 5,217,445, issued to Young et al. On June 8, 1993), capillary channel fibers (ie. , fibers having intra-fiber capillary channels such as those described in U.S. Patent No. 5,200,248, issued to Thompson et al. on April 6, 1993), absorbent foams (such as those described in U.S. Patent No. 5,260,345, issued to DesMarais et al. On November 9, 1993 and U.S. Patent No. 5,268,244, issued to DesMarais et al. On December 7, 1993), thermally bonded air-laid materials (such as those described in the PCT publication. WO 95/10996, entitled "Catamenial Absorbent Structures Having Thermally Bonded Layers for Improved Handiing of Menstrual Fluids and Their Use Catamenial Pads Having Improved Fit and Comfort" presented to name of Richards and others), absorbent sponges, synthetic fibers, polymeric fibers, solidifying agents in polymer gel forming hydrogel, swamp moss, tissue including wraps and sheets of fabric, or any equivalent material or combinations of materials. Suitable absorbent cores comprising foams are described in European applications 0 598 833, 0 598 823 and 0 598 834. Suitable absorbent cores comprising tissue sheets with particles of solidifying agents in hydrogel-forming polymer gel comprised therein, describe in international patent applications WO 94/01069 and WO 95/17868. The configuration and construction of the absorbent core can also vary (for example, the absorbent core may have gauge zones that vary, for example, that are thicker in the center), hydrophilic gradients, superabsorbent gradients, or base weight acquisition zones of lower density and lower average; or may comprise one or more layers or structures. However, the total absorbent capacity of the absorbent core must be compatible with the leading design and the intended use of the sanitary napkin. In addition, the size and absorbent capacity of the absorbent core can be varied to accommodate different uses such as incontinence pads, pant liners, regular sanitary napkins, or sanitary napkins for the night. Preferably, the absorbent articles of the present invention are sanitary napkins that are uniform in thickness. The backsheet 23 and the topsheet 22 are positioned adjacent to the garment facing surfaces 20b and the body facing surface 20a, respectively, of the absorbent core 24 and are preferably attached thereto and to each other by means of fixation (not shown) such as those well known in the art. For example, the backsheet 23 and / or the topsheet 22 can be secured to the absorbent core 24 or to each other by a uniform continuous layer of adhesive, a patterned adhesive layer, or an array of separate lines, spirals or patches of adhesive. adhesive. The adhesives that have been discovered are satisfactory, they are manufactured by H.B. Fuller Company of St. Paul, Minnesota under the designation HL-1258 or H-2031. The attachment means will preferably comprise an open-pattern network of filaments of adhesive as described in US Pat. No. 4,573,986, entitled "Disposable Waste-Containment Garment", which was issued to Minetola et al. On March 4, 1986. A fixing means as an example of an open-pattern network of adhesive filaments comprises several lines of adhesive filaments wound in a spiral pattern as illustrated by the apparatus and methods shown in the US Patent 3,911,173, issued to Sprague, Jr., on October 7, 1975; the Patent of E.U.A. 4,785,996, issued to Zieker et al. On November 22, 1978; and the U.S. Patent. 4,842,666, issued to Werenicz on June 27, 1989. Alternatively, the fixing means may comprise heat links, pressure links, ultrasonic links, dynamic mechanical links, or any other suitable means of attachment or combinations of these fixing means as they are known in the art. The backsheet 23 is impervious to liquids (e.g., menstruation and / or urine) and is preferably fabricated from a thin plastic film, although other flexible liquid impervious materials may also be used. In use, the backsheet 23 is interposed between the absorbent core 24 and the wearer's underwear. The function of the backsheet 23 is to prevent exudates that can be expelled from or inadvertently passing the absorbent core 24, contacting or soiling the wearer's underwear. In this manner, the backsheet 23 may comprise a woven or non-woven material, polymeric films such as polyethylene or polypropylene thermoplastic films, or mixed-body materials such as a film-coated nonwoven material. Preferably, the backsheet is a polyethylene film having a thickness of about 0.012 mm to about 0.015 mm. Exemplary polyethylene films are manufactured by Clopay Corporation of Cincinnati, Ohio, under the designation P18-0401 and by Ethyl Corporation, Visqueen Division, of Terre Haute, Indiana, under the designation XP-39385. The backsheet 23 is preferably embossed and / or mat finished to provide an appearance more to the type of clothing. In addition, the backsheet 23 can allow vapors from the absorbent core 24 to escape (i.e., can breathe) even preventing the exudates from passing through the backsheet 23. As illustrated in Figures 1 and 2, the sanitary napkin 20 before using a three-dimensional structure with a longitudinally oriented seam 50 in the central and rear portions 42, 44 of the absorbent core 24, so that the line of intersection 46 of the plane of longitudinal symmetry S with the surface facing the body 20a has a slope that slopes backward, ie towards the rear end edge 32b, in the central portion 42 and in the portion rear 44 of the absorbent core 24. This can be seen more clearly in Figure 2, where the longitudinal sectional view of the sanitary napkin 20 shows the intersecting line 46 with its declining slope in the central and rear end portions 42 , 44.

The declining slope of said intersection line 46 can be expressed mathematically if said intersection line 46 is consid in a Cartesian system x and in the plane of symmetry S, whthe x-axis is defined by the two points of intersection of the plane of intersection. longitudinal symmetry S with the front end edge 32a and the trailing end edge 32b of the sanitary napkin 20, which corresponds substantially to the points indicated by numerals 32a and 32b in the cross-sectional view of the sanitary napkin 20 illustrated in figure 2 , and whn the surface facing the body 20a looks towards positive values y. With respect to this system of axes, one can form the first derivative of the line of intersection 46. According to the present invention, the first derivative of this line 46 in the longitudinal direction has at least one value that is larger in the central portion 42 of the absorbent core 24 having at least one value at the rear portion 44 of the absorbent core 24. This includes the preferred case, illustrated in Figures 1 and 2, whn the intersection line 46 is always inclined toward the rear end edge 32b with two difft slopes in the central portion 42 and in the rear portion 44, and also alternative embodiments whn, for example, the intersection line 46 slopes upward in the central portion 42 and downward in the portion back 44.

Consecutive values of the first derivative of the intersecting line 46 can continuously fall towards the trailing end edge 32b, which implies that the intersecting line 46 has a curved profile with a continuously declining slope, or, alternatively, the first derivative it can assume difft discrete values on the length of the intersecting line 46. For example, it can be constant in the case of the embodiment illustrated in Figures 1 and 2, whn the intersecting line 46 is formed by two substantially rectilinear portions that they have constant slopes, with a change of slope at a point 48 of the intersecting line 46 positioned whthe central portion 42 of the absorbent core 24 fuses the back portion 44. An intersecting line 46 with the profile described above, provides the sanitary napkin 20 of the present invention with a longitudinally oriented seam 50 in the central and rear portions 42, 44 of the absorbent core 24 having a longitudinal non-linear profile that must match in use the central non-linear groove of the female anatomy extending from the labia majora to the perineum and in the gluteal groove, and approximately the shape schematically indicated in the portions central and rear 42 ', 44' corresponding to the curve G, which also show a corresponding front portion 40 ', illustrated in figure 4, whthe equalization profile of an intersection line 46 in an illustrated sanitary napkin is also shown in figures 1 and 3.

The profile of the longitudinally oriented seam 50 as defined by the intersecting line 46 with its slope going down backwards, can provide the sanitary napkin 20 with an adjustment to the improved user's body. In the preferred embodiment shown in FIG. 1, when going from front to back, the front portion of the seam 50, with a substantially constant slope, should adjust the groove between the labia majora. The subsequent portion of the seam 50 that fills the central and rear portions 42, 44 of the absorbent core 24, with its change in slope, has a profile that is capable of equalizing in use the concave portion downwardly of the central nonlinear slot of the female anatomy in the region that goes from the back of the labia to the perineum, in order to achieve continuous contact with the body. This provides better comfort and more effective interception of fluids as the body releases them. Finally, the rear portion of the longitudinally oriented seam 50, still belonging to the rear portion 44 of the absorbent core 24 and with a constant slope in the embodiment of Figure 1, should extend between the buttocks, but due to its lighter slope, compared to the front portion of the seam, it is able to make contact with the body without causing any tension between the anatomy and this portion of the sanitary napkin, which in turn would cause discomfort, and / or prevent the desired substantially continuous contact between seam 50 and the user's anatomy over all the length of the non-linear groove that extends from the labia majora to the gluteal groove.

In other words, a seam 50 with a profile having a slope that slopes backwards, can obtain more in its non-linear groove, as indicated schematically in Figure 4. The seam 50 with the profile indicated by the line 46 in fact it is able to follow the profile of the groove, indicated by the curve G, by extending beyond the line, indicated by the dotted line in figure 4, which connects two points on the central groove of the surface of the body where the Sanitary towel makes contact with the anatomy, for example, the two points where the sanitary napkin makes contact with the body in correspondence of the front and rear portions of the seam. A seam formed with a linear profile as those known in the art, can not extend beyond this line, since said seam corresponds substantially to this line, and thus can not provide a continuous contact with the body over the entire length of the line. sewing In the embodiment of the present invention illustrated in Figures 1 and 2, the three-dimensional sanitary towel 20 preferably has a low constant thickness that is less than 5 mm, wherein the three-dimensional structure is provided without the use of humps or regions of different thickness, and is an inherent aspect of the sanitary napkin 20, rather than an aggregate aspect, achieved, for example, by bending or joining an initially planar structure. As shown in the embodiment of the present invention illustrated in FIGS. 1 and 2, the front portion 40 of the absorbent core 24 is preferably concave upward, in order to better conform to the user's anatomy in the pubic region. The sanitary napkin 20 illustrated in FIGS. 1 and 2 shows a particularly preferred configuration for the front, central and rear regions 40, 42 and 44 of the absorbent core 24. As seen in cross section, the frontal, central and rear regions of the absorbent core 24 respectively have a V-shape, a W-shape, and an inverted V-shape, as best shown in Figures 5a, 5b and 5c, are illustrated in Figure 1 5b-5b and 5c-5c, respectively. These different shapes provide the sanitary napkin 20 with more capacity to conform to the user's anatomy in a direction substantially perpendicular to the plane of symmetry S already defined. The V shape of the front portion 40 and the inverted V shape of the rear portion 44 are fused together gradually in the central portion 42, where the resulting shape W is predisposed to fit in the area of the labia majora and peri . In use, the longitudinally oriented seam 50 must adjust the longitudinal center groove as described above, while the side portions 51 bent upward can equal the thigh wrinkles, ie, the two grooves that are formed between the body and the body. the legs, typically in the area where the elastic of the panties makes contact with the body. In the preferred embodiment of the present invention illustrated in Figures 1 and 2, the sanitary napkin 20 is provided with an increased capacity to conform to the anatomy of the user than that given simply by the known differentiated transverse shape of the different portions of the absorbent core. 24. The three-dimensional structure of the sanitary napkin 20 before being used, is such that the width of the angle? of the inverted V-shaped portion increases towards the trailing end edge 32b of the sanitary napkin 20 starting from a minimum preferred value to a position corresponding to the fusion of the rear portion 44 with the central portion 42 of the absorbent core 24, in where it substantially corresponds to the angle ß of the central inverted V-shaped part of the W-shaped central portion 42, which in turn is substantially constant over the entire length of this portion 42. Therefore, the rear portion of the seam 50, typically placed in use between the buttocks, its inverted V shape can be more easily extended during product use without being restricted, in order to provide the sanitary napkin with a better adaptation to the user's configuration. A similar feature is preferably provided in the V-shaped front portion 40 of the absorbent core 24, wherein the angle A of the V increases its width toward the front end edge 32a of the sanitary napkin 20 from a minimum preferred value in a point corresponding to the fusion of the front portion 40 with the central portion 42. This would allow the portion of the sanitary napkin 20 that is closer to the front end edge 32a to be more easily flattened in the transverse direction during use, in order to accommodate the relatively flat front of the pubis, at the same time providing a global concave shape to effectively follow the surface of the pubis. The angles of the V-shaped central portion 40 and / or the inverted V-shaped rear portion 44 of the absorbent core 24, and consequently of the entire sanitary napkin 20, can therefore increase towards respective end edges 32a and / or 32b to values of about 180 °, in order to better accommodate the user's anatomy without inducing any substantial tension in the structure, thus providing a better fit and comfort. The preferred aspect of the angles increasing towards respective end edges in the inverted V and V-shaped portions is achieved by giving the front portion 40 and / or the rear portion 44 of the absorbent core 24 a bowl-shaped structure with any means known to one skilled in the art. For example, in the sanitary napkin 20 of the present invention illustrated in FIGS. 1 and 2, this is achieved by cutting a narrow V-shaped portion of material centered over the longitudinal centerline of the initially flat front portion 40 and back portion. 44 of the absorbent core 24, and of the topsheet 22 and the backsheet 23, and with substantially the same length of the front portion 40 and the rear portion 44, and then join the cut edges with known means, for example, by thermal link, on the connecting lines identified as 52 and 54 in Figure 3. The final three-dimensional structure illustrated in Figures 1 and 2 is then achieved by properly folding the non-planar sanitary napkin 20, for example, over the lines of preferential bending, formed in the absorbent core 24 by means of, for example, partial enhancements or cuts, such as the highlights 56 in Figure 3, as can be determined by the person skilled in the art. AC. The presence of this preferred aspect in the sanitary napkin of the present invention illustrated in FIGS. 1 and 2, can be ensured by transversally folding the sanitary napkin 20 in order to over impose the front portion 40 or the rear portion 44 of the absorbent core on the central portion 42 on a bent line approximately in the unfolded sanitary napkin corresponds to a line separating, respectively, the front portion 40 or the rear portion 44 of the central portion 42; in both cases, the fold line will show an angle instead of being rectilinear. In an alternative embodiment of the present invention, a three-dimensional shape similar to that illustrated in Figures 1 to 5c can also be achieved by having in a disposable absorbent article an elastic insert with the desired shape, for example, between the back sheet and the absorbent core. The insert may comprise, for example, only in the central and rear portions of the absorbent core, where the seam with the desired profile must be provided, or it may extend over the entire length of the absorbent article, in order to provide its full shape . The elastic insert can be made of any suitable known material, for example, absorbent or non-absorbent material, and can be produced, for example, by thermofixing to obtain the desired three-dimensional shape, preferably with a constant thickness. The insert can completely provide the three-dimensional structure, or it can alternatively contribute to creating and maintaining said structure in an already formed absorbent article. In accordance with the present invention, the three-dimensional absorbent article, for example, sanitary napkin 20, is applied directly to the wearer's skin. The three-dimensional structure of the absorbent article and its ability to mold and adjust the anatomy of the user, allow the article to remain in place during use, preferably without the need for additional means to secure the article to a garment. In particular, sanitary napkins are applied in the genital region of a typically female user around the liquid discharge area. The word "skin" according to the present invention not only refers to the specific skin of the user, but includes the snotty tissue as well as the hair typically found in the genital region of users of sanitary napkins.

In order to provide fixation of the article in accordance with the present invention to the user's skin, a certain area is provided on the side of the top sheet of the article facing the user, with a topical fixing adhesive also referred to as a body adhesive. A three-dimensional disposable absorbent article in accordance with the present invention, such as sanitary napkin 20, with its improved ability to conform and conform greatly to the user's anatomy, will remain in close contact with the body, and will be provided by the incorporation of a body adhesive on at least part of its surface that faces the body with particular stability during use. The direct adhesion to the skin of the user of the three-dimensional article that fits and molds the body in its optimal position with respect to the anatomy during use, independent of the relative movements between the body and the garment, since it is preferably provided Fixed connection between the article and the garment. This also eliminates the influence of different types of underwear and habits of use in the fit to the body of the article in use. Since the three-dimensional disposable absorbent articles in accordance with the present invention can achieve a closer fit with the anatomy of the body than the known three-dimensional articles, due to their particular shape and their ability to conform to the body, the combination of a body adhesive with an article of the present invention has another advantage, that the article is easily placed, and therefore, it has to adhere to the body, in the optimal position, thus minimizing the risk of adhesion in incorrect positions. As regards the distribution of body adhesive on the body-facing surface 20a of the absorbent article 20, various designs are contemplated: for example, as illustrated in Figures 1 to 3, the body adhesive can be provide as a continuous strip 70 over the peripheral edge of the top sheet, so that a central area of the article is left without adhesive. This will facilitate the positioning of the article, so that the liquid-permeable upper sheet without adhesive thereon is placed adjacent the orifice that emanates liquid from the body, so that the liquid is immediately transported in the absorbent structure of the absorbent article without the possibility of dripping or dirt. However, it is not necessary that the body adhesive be provided in a closed circle around the periphery of the top sheet, but that it be provided in areas of increase such as discrete points or lines, so that the decoupling between the different places Fixation provides additional comfort to the user of said items. It may be preferred to distribute the body adhesive in portions of the body-facing surface 20a of the article 20 that have low relative movement with respect to the body during use, for example, in the front portion 40 of the article, which corresponds in use to the body. pubis of the user. In general, the adjustment to the very close body of the sanitary napkin 20 of the present invention provides a much more predictable location of the area of the surface facing the body 20a of the article intended to be actually reached by the fluids of the body according to leave the body Therefore, it is possible to more accurately distribute the body adhesive in a generally peripheral area of the body-facing surface 20a leaving only a central area of said body-facing surface 20a free of adhesive, wherein said area central is the area of the surface facing the body 20a that should be closer to the orifice that emanates fluid from the body, ie, typically adjacent to the labia majora during the use of the article. The placement of body adhesive on a relatively large portion of the body facing surface 20a of the absorbent article 20 of the present invention, stays better in its place in the article during use, without interfering negatively with the absorption and fluid acquisition capabilities of the article itself. Although any type of body adhesive known in the art according to the present invention may be used, body adhesive compositions such as those described in European patent applications EP 97110727.1 and EP 97110730.5 are particularly preferred, since their specific physical, rheological and adhesive characteristics provide for a painless removal of the absorbent article, while ensuring that no adhesive residue remains on the user's skin or hair. As indicated in EP 97110727.1, the materials useful as body adhesives according to the present invention have rheological characteristics which are measured at a reference temperature of 37 ° C as body temperature and on a frequency scale. It has been discovered that when applying an article with a body adhesive, the contact of the adhesive is formed at a low frequency, while disunity occurs at the speed of removing the article. This speed is expressed as a frequency at 100 rad / s while the low frequency to form the adhesive bond has been found to be in the order of 1 rad / s. Therefore, the frequency scale to be used in accordance with the present invention is between 1 and 100 rad / s. The following series of characteristics must be satisfied: in the frequency scale the variation of the percentage of the elastic modulus G'37 is less than or equal to 150%, preferably less than 100% and more preferable less than 80% of G'37 at 1 rad / s, preferably the variation is less than 10000 Pa in absolute terms. in the frequency scale the variation of the viscous modulus G "37 is not greater than 10000 Pa, preferably not greater than 5000 Pa, more preferable not greater than 1000 Pa. - the value of the ratio G'37 / G" 37 per at least for the frequency scale 1 rad / s to 100 rad / s should preferably be unit or above, more preferably 1.6 or above and most preferably 3.3 or above, preferably not exceeding approximately 50. The rheological behavior can also be related to the values of the Transition Temperature Vitrea Tg. For body adhesives according to the present invention, Tg preferably must be less than -15 ° C, more preferably less than -20 ° C and most preferably less than -25 ° C. In order to meet these requirements of the rheological and physical characteristics of a body adhesive, the following formulation criteria can also be used. It should be noted that most of the compositions useful as a body adhesive have a substantially gel-like structure and are preferably gels. This derives from the fact that: - the prevailing behavior is a liquid material at room temperature a macromolecular or polymeric component is present in minor amounts against the plasticizer. It forms, in the preferred modalities, a three-dimensional network caused by physical or chemical bonds between the molecules. Particularly useful physical links are those that are present in systems containing Thermoplastic Block Elastomers. More specifically, the compositions comprise: from 0.5 to 20%, preferably 5% to 15%, by weight of a macromolecular polymeric substance or a mixture of said substances soluble or swelling in the plasticizer mentioned below. As non-limiting examples, said macromolecular or polymeric substances can be natural and / or synthetic such as natural gums or derivatives, such as natural gums and gelatins, their derivatives and alginates; polyacrylics; polyvinyl alcohol; polyethylene oxide; polyvinylpyrrolidone (PVP) or polyvinyl ethers, their copolymers and derivatives; cellulose derivatives; Thermoplastic elastomers of Block Copolymer and preferably Copolymers in Block of Styrene and more preferably the hydrogenated grades Styrene / Ethylene-Butylene / Styrene (SEBS). Styrene / lsoprene / Styrene (SIS), and Stir l / Eti le non-Propylene / Esti rol (SEPS). - from 51 to 99.5% by weight of a plasticizing substance or a mixture of plasticizing substances, which are liquid at room temperature. As non-limiting examples, the plasticizer may be water, various alcohols (such as in particular glycerol), glycols, polyglycols, liquid polybutenes, natural or synthetic oils such as vegetable oils, mineral oils or combinations thereof. from 0 to 600% by weight of the macromolecular polymer substance of a tackifying resin whose main scope is to adapt the Tg especially in systems based on synthetic polymers, from 0 to 10% by weight and more preferably from 0 to 5% by weight of substances to facilitate and stabilize gel solidification of hydrophilic or hydrophobic liquid plasticizers. These can be for oil systems, for example, the C8 to C22 fatty acids, their metal salts and their polyoxyl derivatives; lanolin derivatives; silica; bentonite, montmorillonite and its derivatives; polyamides, waxes or mixtures thereof. Additives known in the art as preservatives, antioxidants, anti UV, pigments, mineral fillers, rheology modifiers, etc., can also be comprised in amounts of up to 10% each.

When chemical entanglements are formed in the system, an interlacing agent may be present preferably in amounts of up to 5% by weight. Chemical entanglement can also be formed by mutual neutralization of polymers having different functions as in the reaction between acid polyacrylics and polysaccharides. The resulting compositions for body adhesives can be divided into three families according to the nature of the main component, ie liquid plasticizers: 1) Hydrophobic compositions wherein the plasticizer is typically an oil or mixture of oils of vegetable or mineral origin and the polymer is usually a synthetic polymer, preferably an elastomer, soluble or swellable in oil (s). 2) Mixed phase compositions in which hydrophobic and hydrophilic components, possibly in plasticizers and polymers, form two or more separate phases. In such cases, an emulsifier / surfactant is preferably present at a suitable level to form stable emulsions between the incompatible phases. For body adhesives according to the present invention it is preferable that the hydrophobic components prevail against the hydrophilic ones. 3) Hydrophilic compositions wherein typically the plasticizer is water / glycerol / glycols and the like and / or mixtures thereof and the polymer phase is of synthetic (eg, polyacrylic) or natural (eg, natural gums) or mixtures of the same. It is emphasized that, unlike what is already known in the field of medicine and the aforementioned prior art, hydrophilic compositions are not preferred, although Hydrophobic and mixed phase compositions 1) and 2) are preferred in applications of the present invention. This partly depends on technical reasons in the sense that many hydrophilic compositions used in the field of medicine show very low elasticity and cohesion to be useful in the present application. The other reason for preferring hydrophobic or mixed phase compositions is that the application of the present invention in particular in the field of sanitary napkins will include a likelihood that the body adhesive makes contact with the liquid to be absorbed. Since the liquid to be absorbed is of a general aqueous class, contact with a hydrophilic body adhesive would result in some absorption of the body fluids in the body adhesives. Then, this would have the result of changing the rheological characteristics and therefore the function of the body adhesive, causing an unhygienic appearance but would cause the body fluids to remain in direct contact with the skin for an extended period that is typically not desired. by none of the disposable absorbent articles according to the present invention. In addition, this may also constitute a potential disadvantage for the user, since some hydrophilic compositions are potentially good growth media for the growth of many microorganisms including pathogens. In addition, the hydrophilic body adhesive also tends to be perceived as cold and damp, which in the application of a fresh sanitary napkin is not in line with the typical expectations of the consumer. Further problems result from the fact that in particular body adhesives comprising water as the plasticizer, they have a tendency to dry unless sealed in a waterproof package. Disposable absorbent articles in accordance with the present invention may be provided with body adhesive by any of the manners useful in the art. Applying the adhesive to the body facing surface 20a of the absorbent article 20 should not cause major problems for those skilled in the art. For example, the body adhesive can be applied to the desired portion of the body-facing surface 20a of the sanitary napkin 20 of the present invention by spraying it directly onto the topsheet 22. The body adhesive on the article (as is common with adhesives that are secured to the panties) does not need to be protected before use. This protection can be provided by a release liner such as paper treated with silicone or surfactant, with the proviso that this paper is a good release surfactant for the particular selected body adhesive.

In principle, the three-dimensional disposable absorbent article in accordance with the present invention is supported on the user by the body adhesive and does not require additional support to remain in place, however, it is possible to provide, for example, a sanitary napkin with a slip-resistant coating on the side of the backsheet in order to prevent the sanitary towel from gradually coming out of its position. Also, although adhesives that are secured to the pantyhose and are not preferred in accordance with the present invention are not desired, they are not excluded in the context of the present invention. In a preferred alternative embodiment, the three-dimensional disposable absorbent article of the present invention may also comprise specific means for supporting and applying it directly to the body, similar to those described in European patent application EP 97110734.7. Figure 6 shows a perspective view of a sanitary napkin 20 substantially equivalent to that illustrated in Figures 1 to 5c, seen from the side that is away from the user during use, i.e. with the garment facing surface 20b towards the user. The sanitary napkin 20 of Figure 6 further comprises means 58 for supporting and applying it located on the garment facing surface 20b and oriented transversely. The means 58 for holding and applying the sanitary napkin 20 are also referred to as a handling aid. Of course, the means 58 for supporting and applying the sanitary napkin 20 of the present invention should also be used by a person caring for the user, for example, a nurse, who handles the sanitary napkin 20 and applies it to the user's body. In the preferred alternative embodiment of Figure 6, the means 58 for supporting and applying the sanitary napkin 20 comprises a strip of elongated elastic film material 58, oriented perpendicular to the plane of longitudinal symmetry S and located on the garment facing surface. 20b of the sanitary napkin 20, in correspondence of the central portion 42 of the absorbent core 24, in an approximately intermediate position longitudinally between the front end edge 32a and the rear end edge 32b of the sanitary napkin 20. The strip 58 is fixed to the backsheet 23 at its two separate ends 60 arranged on opposite sides of the plane of symmetry S, with an intermediate portion 62 attached to said garment facing surface 20b and defining a space 64 intended for the insertion of at least one user's finger to hold and apply the sanitary napkin 20. In the embodiment illustrated in figure 6, wherein the sanitary napkin 20 has the form t Preferred ridging before use, the space 64 is actually comprised between the intermediate portion 62 of the sanitary napkin, which is concave on its garment facing surface 20b, since it corresponds to the seam 50 on the body-facing surface 20 a. Typically, the separated ends 60 of the strip 58 are fixed by known means, for example, with an adhesive, or by thermobonding, to the garment facing surface 20b of the backsheet 23 at intermediate locations between each folded line corresponding to the enhancements 56, and the respective longitudinal edge 31. The user can put the sanitary napkin 20, preferably with the release liner protecting the body adhesive still in place, in the palm of his hand with the surface facing the garment 20b making contact with the hand and with the front end edge 32a facing the wrist, at the same time typically inserting one of its fingers, eg, the middle finger, into the space 64 between the intermediate portion 62 of the strip 58 and the backsheet 23. Therefore, the user can hold the sanitary napkin 20 in his open hand without exerting any force, also due to the elasticity of the preferred material constituting the strip 58, with substantially the front portion of the sanitary napkin 20 in its palm. After the exposure of the body adhesive, typically performed by removing the protective release liner, the application to the body can then be easily performed by the user with a single movement of his open hand, which is simple and understandable as putting an empty hand on the body. In addition, the movements of the hand and fingers allow the user to completely control the manipulation of the sanitary napkin 20 during its application to the body, using the sensitivity of the touch of the fingers to find the correct position for the sanitary napkin 20. In In particular, in the preferred embodiment of the present invention, the finger inserted into the space 64 is substantially aligned with the seam 50 on the surface facing the body 20a of the sanitary napkin 20, and can therefore provide guidance to control the placement of the towel 20 in the anatomy of the body, that is, with the seam 50 appropriately registered with the longitudinal non-linear groove of the female anatomy extending from the labia majora to the gluteal groove. The front portion of the seam can be easily identified by the user with his finger inserted in the space 64, and used as a reference for directing the sanitary napkin in an optimal position on the body. The operating aid 58 of the preferred alternative embodiment of FIG. 6 allows one to take advantage of the body adhesive on the surface facing the body 20a of the sanitary napkin 20 of the present invention, particularly when it is preferably provided as a peripheral area of the sanitary napkin 20 of the present invention. the top sheet, so that an area of the article is left without adhesive. In fact, the user can more easily direct the sanitary napkin 20 to the correct place by means of the operating aid 58 without touching the surface facing the body 20a of the towel comprising the body adhesive 70, further reducing the risk that the body adhesive sticks to the skin of the user in the wrong place before having properly placed the sanitary napkin 20. The operating aid constituted by the strip 58 also allows an easy removal of the hand once the sanitary napkin 20 is in place, without impairing or modifying the position of the towel 20. Since in the preferred embodiment of the present invention described so far, the three-dimensional sanitary towel 20 does not comprise a system that is secured to the panty, but uses a body adhesive for holding the sanitary napkin 20 surely in contact with the body of the user, the operating aid of the present invention illustrated in the figure 6 also preferably allows easy removal and, possibly, a subsequent reapplication of the sanitary napkin 20 of the body in order to use the bath, or to make a review of the product, or in any case in order to finally dispose of the product. In fact, the wearer can easily grasp the sanitary napkin 20 while using it by placing his hand in substantially the same manner as for the application, with one of his fingers inserted into the space 64 between the unattached portion 62 of the strip 58 and the back sheet 23. Therefore, the sanitary napkin 20 can be removed from the body and safely held by the user; the driving aid can also be used to temporarily store the sanitary towel, for example, when using the bath, in the user's hand, without the need to actually hold it with the fingers, or to exert any force on it. The operating aid constituted by the strip 58 allows in any case the user to handle / manipulate the sanitary napkin 20 when making contact with its surface facing the garment 20b only, thus avoiding any possible contact with the body adhesive on the surface which looks to the body 20a, and further protecting the user's hand from a surface facing the possibly dirty body 20a. In absorbent articles having a three-dimensional shape before use, such as the sanitary napkin 20 in the preferred embodiment described above, the operating aid may also preferably contribute to maintaining the three-dimensional shape of the article during use, for example, in case of body movements that can damage the proper fit of the product, or when in general there is a risk of changing the three-dimensional shape that fits the body. Otherwise, the operating aid, for example, constituted by the strip 58 illustrated in FIG. 6, remains aligned or bent or loose on the surface facing the garment 20b of the product and does not impair the operation of the product. In alternative embodiments, the handling aid may be constituted by more than one strip of material, or by one or more threads, while the material may also be non-elastic. The operating aid can also be constituted by a strip arranged as a loop and applied to the surface facing the garment 20b of the article, or by a series of loops, which must allow the insertion of at least one finger of the user. The operating aid can also be activated by the user, for example, by applying to the garment facing surface of the absorbent article just before use; alternatively, a handling aid, for example, constituted by a strip 58 can be detached, for example, at one of its ends from the garment-facing surface of the absorbent article and then replaced in a different place, in order of, for example, controlling or partially adapting a three-dimensional shape already provided in the absorbent article, or to modify the available space 64 for the insertion of at least one finger of the user. Therefore, a handling aid preferably constituted by a strip 58 can be attached to the garment facing surface 20b of the absorbent article, either at one or both ends 62, for example, by means of a releasable adhesive, or of a hook or loop type mechanical insurance, such as that manufactured under the trade name VELCRO. A handling aid in the form of a loop can be modified by the user in order to change the diameter of the loop, and thus the space available for the insertion of the finger. The operating aid of the present invention does not necessarily extend over the entire width of the absorbent article, in order to define a suitable space for the insertion of at least one finger of the user, which is capable of achieving a sufficiently firm fit with said user. at least one finger As illustrated in the preferred embodiment of Figure 6, the operating aid does not extend in the longitudinal direction over a major portion of the length of the disposable absorbent article; preferably, it extends over less than 10% of said length, a narrow strip with a width being more preferably extending in said longitudinal direction of approximately 1 cm. The absorbent article of the present invention may further comprise an odor control material for controlling unpleasant odors associated with absorbed body fluids. Any known odor control agent or any combination thereof that may be included in a disposable absorbent article, including other materials such as binders and / or substrates, may be comprised in the absorbent article of the present invention as the odor control material. Absorbent structure, for example, active carbon coated with or in addition to the other odor control agents, in particular zeolite or clay materials, may be incorporated into the absorbent structure. The odor control material may be incorporated into the absorbent article by methods known in the art, for example, laminate or in the absorbent core or mixed with the absorbent core, and in any desired form, for example, as discrete particles. The incorporation of odor control material in the absorbent articles of the present invention is particularly advantageous, since the application of the absorbent article directly to the user's skin by means of the body adhesive can provide an odor seal that prevents odors of the liquid absorbed or formed from the absorbed liquid reach beyond the absorbent article. The absorbent articles of the present invention, in particular sanitary napkin 20, have a length that can vary between typical values commonly used for different sizes of said absorbent articles intended for substantial external deposition adjacent to the wearer's body. In particular, the central and rear portions 42 and 44 of the absorbent core 24 do not have a length that is smaller than the total maximum length of the major lips of an average user.

Other alternative means for providing a disposable absorbent article of the preferred three-dimensional structure, other than cutting, joining and folding, already explained, can be achieved by providing an absorbent article with an extensible elastic portion that can be deformed to produce a structure equivalent to the preferred, for example, by stretching it in the transverse direction in the central and rear portions of the absorbent core. In an alternative embodiment of the present invention, the three-dimensional absorbent article may have two fins (not shown) each of which is adjacent to and extends laterally from the lateral edge of the absorbent core. The flaps are configured to cover the edges of the wearer's panties in the crotch region, so that the flaps are disposed between the edges of the wearer's panties and the wearer's thighs. The fins serve to prevent the body and the user's panties from becoming soiled by menstrual fluid, preferably by forming a double wall barrier on the edges of the panty. The fins can be constructed of various materials including materials used for the topsheet 22, backsheet 23, combinations thereof, and can be a sheet with fabric in the center. In addition, the fins can be an element fixed to the main body of the three-dimensional absorbent article or can comprise extensions of the upper sheet 22 and / or back sheet 23. However, it is recommended that the fins have a liquid-impermeable back sheet to prevent bodily fluids that reach the fins dirty the edges of the user's panties.

In accordance with the present invention, a body adhesive may also be applied, for example, at least a portion of the body-facing surface of said fins, in order to cause the fins to adhere to the inner part of the fins. thighs of the user. This would allow the fins to remain outside the leg elastics when the pant is pulled, thus preventing the fins from creasing or bending towards the garment-facing surface of the absorbent article, instead of covering the edges of the panty user. Preferred fins that are suitable or can be adapted to the three-dimensional absorbent article of the present invention are described in the U.S. Patent. No. 4,687,478, issued to Van Tilburg on August 18, 1987; Patent of E.U.A. No. 4,589,876, issued to Van Tilburg on May 20, 1986; and Patent of E.U.A. No. 4,608,047, issued to Mattingly on August 26, 1986. Optionally, the three-dimensional absorbent article may comprise components that naturally surround the sides of a wearer's panties. Sanitary napkins having components that naturally surround the sides of a wearer's panties suitable for use with the three-dimensional absorbent article of the present invention are described in U.S. Pat. No. 5,584,829 entitled "Absorbent Article having Panty Covering Components that Naturally Wrap the Sides of Panties", issued to Lavash et al. On December 17, 1996 and Patent of E.U.A. No. 5,558,663 entitled "Absorbent Articles Having Undercover Covering Components with Zones of Extensibility", issued to Weinberger et al. On September 24, 1996. In another embodiment of the present invention, the three dimensional absorbent article may also comprise side wraps, for example, as described in the European patent application EP 96120739.6. In other embodiments of the present invention, the three-dimensional absorbent article may also comprise additional elements, such as an acquisition layer or a secondary topsheet positioned between the topsheet 22 and the absorbent core 24 or, alternatively, at any other suitable position. Although the disposable absorbent article of the present invention has been described with reference to a sanitary napkin, it can be beneficially used in the context of other disposable absorbent articles such as panty-hose and incontinence articles. The absorbent article disposable in this way can have all those characteristics and parts that are typical for products in the context of their intended use.

Claims (8)

1. - A three-dimensional disposable absorbent article having a body-facing surface and a garment-facing surface, a plane of longitudinal symmetry, a front end edge and a trailing end edge, and comprising a liquid-permeable top sheet, back sheet attached to said upper sheet and an intermediate absorbent core of said upper sheet and said back sheet, said absorbent core has a front portion, a central portion and a rear portion, said surface facing the body defines a line formed by the intersection of said surface that faces the body with said plane of symmetry, said line is present in a Cartesian system xy that is within said plane of symmetry, with the axis x defined by the two points of intersection of said plane of longitudinal symmetry with said front end edge and said rear end edge, and with said surface facing the body facing positive values ivos and, said line has a first derivative with respect to said Cartesian system xy, wherein at least one value of said first derivative of said line in said central portion of said absorbent core is larger than at least one value of said first derivative of said line in said rear portion of said absorbent core, said article characterized in that: it comprises in at least part of said body facing surface an adhesive for fixing topical adhesive of said article to user of said article.

2. A disposable absorbent article according to claim 1, wherein all the values of said first derivative in said central portion are larger than the values of said first derivative in said rear portion.

3. A disposable absorbent article according to claim 1 or 2, wherein said first derivative is constant in said central portion or in said rear portion, or both.

4. A disposable absorbent article according to any preceding claim, wherein the cross section of said article in said front portion is V-shaped defining an angle "a", said central portion being W-shaped defining an angle β, and in said back portion are in the form of an inverted V defining an angle,, wherein the angle α of the V in said front portion increases toward said front end edge, and the angle de of the inverted V in said rear portion increases toward said angle. rear end edge.

5. A disposable absorbent article according to any preceding claim, wherein: said adhesive has an elastic modulus at a temperature of 37 ° C, G'37 and has a viscous modulus at a temperature of 37 ° C, G "37 where G'37 is less than 20,000 Pa, and G" 37 is less than 15,000 Pa, said adhesive is selected to have a dynamic elastic behavior, so that the difference, _G'37, of G'37 at a frequency of 1 rad / sec and G'37 at a frequency of 100 rad / sec is not greater than 150% of G'37 at a frequency of 1 rad / sec, preferably not greater than 10000 Pa, and - said adhesive is selected to have a dynamic viscous behavior, so that the difference, _G "37, of G" 37 at a frequency of 1 rad / sec and G "37 at a frequency of 100 rad / sec is not greater that 10000 Pa, preferably not greater than 5000 Pa, and where the value of the ratio G'37 on G "37 on the frequency scale 1 - 100 rad / s is greater than or equal to 1, preferably greater than or equal to to 1.6 and very preferable greater than or equal to 3.3.

6. A disposable absorbent article according to claim 5, wherein said adhesive is a composition of materials comprising - from 51% to 99.5% by weight of a plasticizer compound or composition that is liquid at 20 ° C; 0.5% to 20% by weight of a polymeric compound or composition that is soluble or can swell in said plasticizer compound or composition; a sticky resin in an amount of 0% to 600% by weight of said polymeric compound or composition.

7. An absorbent article according to claim 5 or 6, wherein said adhesive is at least partially hydrophobic, preferably 80% by weight of said adhesive consists of hydrophobic components and very preferably all the components of said adhesive are hydrophobic.

8. A disposable absorbent article according to any preceding claim, wherein said disposable absorbent article is a sanitary napkin or a pantiprotector, and said body adhesive is provided in a peripheral area of said surface that faces the body leaving at least a central area of said surface facing the adhesive-free body, said central area being that area of said body-facing surface, which is adjacent to the labia majora during the use of said disposable absorbent article. SUMMARY A disposable, three-dimensional absorbent article having a body facing surface and a garment facing surface, a longitudinal symmetry plane, a front end edge and a trailing end edge, and comprising a permeable topsheet to the liquid, a back sheet attached to the top sheet and an intermediate absorbent core to the top sheet and the back sheet. The absorbent core has a front portion, a central portion and a rear portion, and comprises a longitudinally oriented flange in the central and posterior portion, having a profile that provides an adjustment to the increased body. The article is intended for direct attachment to the user's skin and comprises an adhesive on the surface facing the body. cm1570q.p &g