MXPA06014528A - Disposable absorbent article having backsheet strips - Google Patents

Abstract

A disposable absorbent article includes two laterally opposing longitudinally extending backsheet strips attached to an exterior surface of an absorbent assembly in laterally opposing attachment zones. Each backsheet strip may include a water-impermeable layer and may be extensible. The absorbent assembly includes laterally opposing side flaps which may be formed by folding portions of the absorbent assembly laterally inward. A longitudinally extending elastic gathering member is attached to each side flap adjacent to its proximal edge. When the article is worn, the elastic gathering members contract and raise the side flaps to form side barriers. The absorbent assembly includes an absorbent core that may contain superabsorbent particles, which may be contained inside pockets. A portion of the absorbent assembly such as the portion that lies between the backsheet strip attachment zones may be extensible and may include a water-impermeable layer.

Description

ABSORBENT ARTICLE DISPOSABLE WITH STRIPS IN THE LOWER CANVAS FIELD OF THE INVENTION This invention relates to disposable absorbent articles such as disposable diapers and other articles intended for use in incontinent persons.

BACKGROUND OF THE INVENTION Disposable absorbent articles are designed to absorb and contain body waste in order to prevent soiling of the user's body and clothing as well as the bedding or other objects with which the user is in contact. As the use of disposable absorbent articles has become widespread, their complexity has increased with the incorporation of additional features that are intended to improve their performance and appearance. Along with the increase in complexity, the costs of materials and manufacturing processes have also increased. As a result, the prices at which these items are sold have risen to levels that are inaccessible to many potential buyers around the world. Therefore, there is a need for a simple disposable absorbent article.

BRIEF DESCRIPTION OF THE INVENTION The present invention provides a disposable absorbent article that includes two strips on the lower canvas that extend longitudinally opposite each other. lateral form and which are attached to an outer surface of an absorbent unit in laterally opposed adjustment regions. Each strip of the lower canvas may include a waterproof layer and may be extensible. The absorbent unit includes laterally opposed side flaps which may be formed by portions of the absorbent unit that fold inward in a lateral direction. An elastic shirring member extended in the longitudinal direction is attached to each side flap adjacent its proximal edge. When the article is used, the elastic gathers will contract and lift the lateral fins forming lateral barriers. The absorbent unit includes an absorbent core which may include superabsorbent particles that may be contained within the bags. A portion of the absorbent unit such as the portion that lies between the adjustment zones of the lower canvas strips may be extensible and may include a water impermeable layer.

BRIEF DESCRIPTION OF THE FIGURES In the accompanying figures, similar reference numbers identify the corresponding structural elements, which may or may not be identical in the various illustrative embodiments that are depicted. Some of the figures will have been simplified by omitting selected elements in order to show other elements more clearly. These omissions of elements in some figures are not necessarily indicative of the presence or absence of particular elements in any of the illustrative embodiments, except to the extent explicitly indicated in the corresponding written description. In the figures and in the written description, the lowercase letters appended to the reference numbers indicate, in general, symmetrical elements; for example, Left and right side edges of the absorbent unit 200 are identified by the reference numerals 237a and 237b, respectively. A reference number without a lowercase letter attached identifies all the elements to which that specific reference number corresponds, for example, a lower canvas formed by individual left and right portions can be identified in its entirety by the reference number X, while the left and right portions are identified individually by the respective reference numbers Xa and Xb; in this way, the textual reference to a structure identified with X includes the elements Xa, Xb, and so on. Figure 1 is a plan view of an illustrative disposable absorbent article in the form of a diaper 20, which is presented in its flat, unconstrained state, ie, without the contraction induced by the elastic members. In Figure 1, the inner portion of the diaper 20 that is oriented internally towards the user and makes contact with it is shown facing the viewer. Figure 2 is a plan view of the diaper 20 of Figure 1 in its flat state and without contracting; with the outer portion of the diaper 20 facing outward and further away from the user is shown facing the viewer. Figure 3, Figure 4, and Figure 5 are sectional views of the diaper 20 of Figure 1 and Figure 2 taken in the respective cut lines 3-3, 4-4, and 5-5. In these sectional views, the inner portion of the diaper 20, which faces inwards towards the user and comes into contact with the latter, is shown facing upwards. Figure 6 is a simplified view in lateral elevation of an illustrative diaper 20 placed around the lower torso of a wearer. Figure 7 is a front elevation view of the diaper 20 of Figure 6 placed around the lower torso of a wearer.

Figure 8 is a rear elevation view of the diaper 20 of Figure 6 placed around the lower torso of a wearer. Figure 9 is a plan view of an illustrative fragment of a weft material formed. Figure 10 is a simplified left side elevational view of an illustrative diaper 20 that includes adhesive fastening patches placed around the lower torso of a wearer. Figure 11 is a simplified right side elevational view of the diaper 20 of Figure 10 including adherent holding patches positioned around a user's lower torso. Figure 12 is a simplified plan view of another illustrative disposable absorbent article in the form of a diaper 20, which is shown in its flat, un-collapsed state, with its inner portion facing the viewer. Figure 13 is a simplified plan view of the diaper 20 of Figure 12 with its outer portion facing the viewer. Figure 14 is a perspective view of an illustrative diaper 20, which is shown in its contracted, unstressed state, with its inner portion facing upwards. Figure 15 is a plan view of an illustrative absorbent unit 200, shown separately from the other portions of an illustrative diaper and with its interior portion facing the wearer. Figure 16 is a sectional view of the absorbent unit of Figure 15 taken in section line 16-16. Figure 17 is a sectional view of the absorbent unit of Figure 15 taken in the section line 17-17.

Figure 18 is a sectional view of an illustrative absorbent unit 200 showing the details of an illustrative absorbent core having particles of superabsorbent material within the bags. Figure 19 is a sectional view of an illustrative absorbent unit 200 having an additional base sheet 226, taken on a line of section corresponding to section line 4-4 in Figure 1. Figure 20 is a view in Another illustrative disposable absorbent article plant in the form of a diaper 20, which is shown in its flat state without contracting, with its inner portion facing the viewer. Figure 21 is a plan view of another illustrative disposable absorbent article in the form of a diaper 20, which is shown in its flat, un-collapsed state, with its inner portion facing the viewer. Figure 22 is a plan view of a diaper 20 of Figure 21 in its flat, un-collapsed state, with its outer portion facing the viewer. Figure 23 is a sectional view of the diaper 20 of Figure 21 and Figure 22 taken on the section line 23-23, with its inner portion facing upwards. Figure 24 is a plan view of another illustrative disposable absorbent article in the form of a diaper 20, which is shown in its flat, un-collapsed state, with its inner portion facing the viewer.

DETAILED DESCRIPTION OF THE INVENTION In this description, the following terms have the following meanings: The term "absorbent article" refers to a device that absorbs and contains liquid and, more specifically, refers to a device that is placed against or close to the body of the user to absorb and contain the various exudates discharged from the body. The term "diaper" refers to an absorbent article that is generally worn by infants and incontinent persons around the lower torso in such a manner that it surrounds the wearer's waist and legs and is specifically adapted to receive and contain waste. urinary and fecal The term "disposable" refers to the nature of the absorbent articles which, in general, are not intended to be washed, or, failing that, to be restored or reused as an absorbent article, that is, the intention is that they be discarded after a only use and preferably, recycled, converted into fertilizer or otherwise, discarded in a manner compatible with the environment. The term "longitudinal" refers to a direction that goes from one edge of the waist to the opposite edge of the waist of the article, usually parallel to the maximum linear dimension of the article. Directions within ± 45 ° of the longitudinal direction are considered "longitudinal". The term "lateral" refers to a direction that goes from a lateral edge to the opposite lateral edge of the article, usually at right angles to the longitudinal direction. Directions within ± 45 ° of the lateral direction are considered "lateral". The term "disposed" refers to an element that is united and located in a specific place or located in a unitary structure with other elements. The term "attached" refers to elements that are connected or joined by clamping, adhesion, binding, etc. by any suitable method for the elements to join together and their constituent materials. Many are known suitable methods for holding elements together, including adhesive bonding, pressure bonding, thermal bonding, mechanical fastening, etc. These fastening methods can be used to link elements together over a certain area continuously or intermittently. The term "adherent" refers to the ownership of a material that, once placed, adheres to itself but does not adhere significantly to other materials. The terms "water-permeable" and "water-impermeable" refer to the penetrability of the materials in the context of the intended use of the disposable absorbent articles. Specifically, the term "water permeable" refers to a layer or stratified structure having interconnected pores, openings and / or voids that allow liquid water to pass through its thickness in the absence of a pressing force. On the other hand, the term "waterproof" refers to a layer or a stratified structure through whose thickness liquid water can not pass in the absence of a pressing force. A layer or stratified structure which is impermeable to water as Definition can be permeable to water vapor, that is, "permeable to water vapor". This stratified layer or structure permeable to water vapor is commonly known in the industry as "permeable". As is well known in the industry, a common method for measuring the water permeability of materials commonly used in absorbent articles is a hydrostatic pressure test, also called a hydrostatic head test or simply a "hydro head" test. The compendiums of suitable methods, well known for hydrostatic pressure testing, are approved by INDA (formerly the International Nonwovens and Disposable Association), now known as the Association of the Nonwoven Fabrics Industry (Association of the Non-Woven Fabrics Industry) and EDANA (European Disposables And Nonwovens Association). The terms "proximal" and "distal" refer, respectively, to the location of an element relatively near or far from the center of a structure, for example, the proximal edge of a longitudinally extending element and located closer to the axis longitudinal than the distal edge of the same element in relation to the same longitudinal axis. The terms "inside" and "outside" refer, respectively, to the location of an item to be placed against or toward a user's body when the absorbent article is used and the location of an item to be placed against or toward any clothing that It is used on the absorbent article. The synonyms of "inner" and "outer" include, respectively, "internal" and "external" and also "inside" and "outside." Also, when the absorbent article is oriented so that its interior is upward; for example, when it is extended when preparing it to place the user on top of it; Synonyms include "upper" and "lower" and "upper" and "lower", respectively.

Description of Illustrative Diaper Modalities As shown in Figures 1, 2, 3, 4, and 5, an end portion of the illustrative diaper 20 is configured as an anterior waist region 36; the longitudinally opposite end portion is configured as a rear waist region 38, and an intermediate portion is configured as a crotch region 37. The basic structure of the diaper 20 includes an absorbent unit 200, which has a leading edge 236, a trailing edge 238, a left side edge 237a, a right side edge 237b, an inner surface 202, and an outer surface 204. A shaft longitudinal 42 extends through the midpoints of the leading edge 236 and of the trailing edge 238 and a lateral axis 44 extends through the midpoints of the left lateral edge 237a and the right lateral edge 237b. The absorbent unit 200 has side flaps 247a and 247b laterally opposed, which are described in detail later. The basic structure of the diaper 20 also includes two strips of the bottom sheet extending in the longitudinal direction and laterally opposed, referred to as the left strip of the bottom sheet 100a and the right strip of the bottom sheet 100b. The strips of the lower canvas have their respective left edge of the anterior waist 136a and right edge of the anterior waist 136b, left edge of the posterior waist 138a and right edge of the rear waist 138b, proximal edge of the left strip 156a and proximal edge of the waist. right strap 156b, left inner surface 102a and right inner surface 102b, left outer surface 104a and right outer surface 104b. Together, the two strips of the lower panel define a left side edge 137a and a right side edge 137b of the diaper 20. As shown in Figures 2, 3, 4, and 5, the strips 100a and 100b of the lower canvas and the canvas The lower cover 25 of the absorbent unit 200 are joined in longitudinally opposite, laterally extending adjustment zones, such as the illustrative adjustment zones 220a and 220b. As shown in Figures 6, 7, and 8, when the diaper 20 is worn over the wearer's lower torso, the anterior waist edges 136a and 136b of the strips of the lower canvas, the leading edge 236 of the absorbent unit, the posterior waist edges 138a and 138b of the strips of the lower canvas, and the trailing edge 238 of the absorbent unit surround the user's waist, the side edges 137a and 137b surround the user's legs, the crotch region 37 is located usually between the user's legs, and the absorbent unit 200 extends from the anterior waist region 36 through the region of the crotch 37 to the posterior region of the waist 38. A portion or the total of each strip of the lower canvas may be formed of an elastically extensible material or materials. Alternatively, or additionally, a portion or all of each of the strips of the lower canvas may be made extensible to a greater degree than the inherent extensibility to the material or materials used to manufacture the lower canvas strip. In the same way, a portion or all of the absorbent unit can be made of an elastically extensible material or materials. Alternatively, or additionally, a portion or all of the absorbent unit may be extensible to a degree greater than the extensibility inherent in the material or materials used to make the absorbent unit. Such additional extensibility may be desirable to allow the diaper 20 to fit the wearer's body when the diaper is in movement. The additional lateral extensibility may be particularly desirable to allow the wearer of the diaper to extend the anterior region of the waist and / or the posterior region of the waist to encircle the wearer's waist, i.e. to adapt the measurement of the waist and the waist. fit from a diaper to an individual user. This lateral extension in the waist region or regions may provide the diaper, in general, with an hourglass shape and impart a perfect fit appearance when worn over the body. In addition, greater extensibility may be desirable to minimize the cost of the diaper, since a relatively smaller amount of material is needed when it becomes extensible, as described above. To provide a better fit at the user's waist, in some embodiments additional lateral extensibility is provided in the absorbent unit 200 only between the laterally opposed adjustment areas 220a and 220b, wherein the absorbent unit 200 and the strips 100a and 100b of the canvas lower are joined together instead of be attached to the absorbent unit. The additional extensibility in the strips of the lower canvas and / or absorbent unit can be provided in different ways. For example, the material or materials used to manufacture the strips of the lower canvas and / or absorbent unit can be folded by any of the many known methods. Alternatively, all or a portion of the lower canvas strips and / or absorbent unit may be made of a formed weft material or laminated and formed weft materials such as those described in U.S. Pat. no. 5,518,801, issued May 21, 1996 in the name of Chappell et al. An illustrative fragment 300 of this type of formed weft material 305 is shown in Figure 9. This formed weft material 305 includes different laterally extending regions 310 in which the original material has been altered by embossing or other method of deformation to generate a pattern of crests 312 and alternating valleys 314 oriented generally in the longitudinal direction. The formed web material 305 also includes unchanged laterally extending regions 316 located between the altered regions 310 that extend laterally. This type of formed weft material 305 may extend laterally beyond its original dimension with the application of a relatively smaller force than is required to extend the same material to the same extent, when it is undeformed. In particular, the application of opposing divergent forces generally directed perpendicular to the crests 312 and valleys 314 extends the weft material formed along an axis between the opposing forces and generates a strength of resistance and contraction mainly in non-uniform regions. altered 316. This strength of resistance is relatively less than the resistance force that is generated by the same material in its undisturbed form when it extends to the same degree, at least to an extent to which the crests and valleys in the altered regions flatten and begin to contribute to the resistance force. Accordingly, those formed weft materials exhibit an extensible behavior similar to that of traditional elastic materials, with the range of extensibility suitable for absorbent articles, but they can be made from relatively cheaper materials that are not inherently elastic and therefore, using them can be advantageous in terms of the manufacturing cost of the absorbent articles. In addition, the different portions of the strips of the lower canvas and / or of the absorbent unit can be formed to have different ranges of extensibility and / or be extensible to a greater or lesser degree when they are subject to a given level of opposite tension forces i.e. , so that they can extend relatively more or less easily. This differential extensibility may be convenient, for example, so that one of the waist regions or both may extend relatively more in the lateral direction or with relatively greater ease compared to the crotch region.

Description of the lower canvas strips The diaper 20 includes two strips of the lower canvas extending in the longitudinal direction opposite laterally referred to as the left strip of the lower canvas 100a and the right strip of the lower canvas 100b, as shown in Figures 1, 2. , 3, 4, and 5. The lower canvas strips may be made of a non-woven material, for example, a synthetic non-woven fabric such as polypropylene, polyester or rayon, of thermally bonded or carded filaments. Alternatively or additionally, each strip of the lower panel may include a water impermeable layer that is formed of a suitable material, for example, a polyethylene or other polyolefin film, a microporous ventilated film, a hydrophobic nonwoven fabric, or a film formed by coextruded polyolefin layers. For example, a suitable co-extruded film is that distributed by Clopay Plástic Products Co. of Mason, Ohio, USA. with the designation M18-327. A multilayer bottom sheet strip, such as a sheet of a film and a non-woven fabric may also be suitable and may be oriented with the nonwoven fabric arranged externally to provide the feel and appearance of an outermost layer similar to a non-woven fabric. genre, with the non-woven fabric disposed internally to separate the film from the wearer's skin, or with the non-woven fabrics arranged both externally and internally. The anterior and posterior waist region can be joined in various ways to surround the user's waist and legs. For example, separate fastening devices such as safety pins, separate tapes, a separate strip or strips for tying and / or a separate belt can be used for this purpose. As an alternative, or additionally, fastening elements may be incorporated in the disposable absorbent article that allow a person to place the diaper on the wearer's body without the separate fastening devices or together with any of these. Many of the suitable types of these built-in fasteners are well known, including, for example, tapes, adhesives, tabs of adhesive tape, binding strips, buttons, hooks, loops, snaps, other forms of mechanical fasteners, Adhering patches, etc. Some mechanical fasteners may be adapted to engage with a non-woven fabric, for example, a layer of non-woven fabric of a laminated bottom sheet. The junction between the anterior waist region and the posterior waist region can be reopened and readjusted to regulate the diaper fit on the wearer's body and to be able to see the inside of the diaper without having to remove it from the body. From alternative way, the union can be permanent, that is to sayWhen opening it, a portion of the diaper is destroyed, for example, a portion of the diaper is torn or the fused side seams are broken. Adherent fastening patches can be formed by the application of an adherent material on a substrate. Adhesive material can be applied in any of several patterns, for example, a continuous film, different points, strips, polygons, etc. and / or separate and interconnected geometric elements that describe a grid. Suitable synthetic adherent products are distributed by Andover Coated Products, Incorporated, of Salisbury, Massachusetts, USA. and are described in U.S. Pat. no. 6,156,424, granted on December 5, 2000 in the name of Taylor. Said adhesive fastening patches may be disposed on the outside of the diaper 20. For example, as shown in Figures 1, 2, 3, 5, 10 and 11, the adherent holding patches 110a and 110b may be disposed on the outer surfaces. of the respective lower canvas strips 100a and 100b in the anterior waist region 36. In this illustrative embodiment, the adherent adhesive fastening patches 120a and 120b, operatively complementary, are disposed on the inner surfaces of the respective strips 100a and 100b of the canvas bottom in the back waist region 38. When the diaper 20 is worn as shown in Figures 10 and 11, the adherent patch patches located therein overlap the adherent patch patches located on the outside and the patch patches on the outside. overlapping adherent fasteners serve to adjust the anterior waist region 36 to the posterior waist region 38 on the sides of the diaper 20. The Figure shown in these figures is adapted to hold the back on the front. Alternatively, the above adherent holding patches may be disposed on the inside of the diaper 20 and the subsequent adhesive attaching patches may be disposed on the outside of the diaper 20 in order to adapt the configuration so that the anterior part is held on the back. Alternatively, the adhesive fastening patches may be arranged in a reversible configuration that is adapted to offer the diaper user the two fastening options, ie, the back on the anterior or the anterior on the posterior, in accordance with personal preference. For example, adherent holding patches disposed on the outside and inside of the diaper 20 may allow a backward adherent holding patch to overlap a prior adherent holding patch or the previous one to overlap the posterior. When the underlying portion of the diaper is extensible, it is preferable that the adhesive fastening patches have a similar level of extensibility so as not to limit the underlying extensible portion of the diaper. Alternatively, the adhesive tape tabs may be attached to the diaper 20 and may be used to hold both the rear waist region 38 and the anterior waist region 36 together. For example, as shown in Figures 12 and 13, the tabs of adhesive tape 1 14a and 1 14b, laterally opposite, may be attached to or adjacent to the respective strips 100a and 100b of the lower canvas at the side edges 137a and 137b of the diaper 20. Suitable adhesive tapes are distributed by 3M Corporation of St. Paul, Minnesota, USA, under the designation XMF99121 and by Avery Dennison Corporation, Specialty Tape Division, Mentor, Ohio, USA, under the designation F4416. Optionally, the fastening sheets can also be attached to the diaper 20 and used together with said tabs of adhesive tape. For example, the fastening sheets 1 16a and 1 16b may be attached to the outer surfaces 104a and 104b of the respective strips 100a and 100b of the lower canvas as shown in Figures 12 and 13. When a fastening canvas is provided, the adhesive tape tabs adhere to the fastening canvas to hold both the rear waist region 38 and the back anterior waist region 36. The holding canvas serves to distribute the tension force transmitted by each adhesive tape tab over an area larger than the adherent area of the tongue and can support a portion of the tensile force by releasing itself thus a portion of the force exerted on the underlying portion of the diaper, such as, for example, the strips of the lower canvas. Thus, it may be desirable to incorporate such a clamping canvas, for example, so that it is possible to use a relatively inexpensive and relatively weak material for the underlying portion of the diaper. When mechanical fasteners are used in place of tabs of adhesive tape, the fastening canvas may have a surface or fasteners with that fastener, for example, hoops to which hooks are attached. When the underlying portion of the diaper is extensible, it is preferable that the fastening fabric have a similar level of extensibility so as not to limit the underlying extensible portion of the diaper.

Description of the absorbent unit As shown in Figures 1, 2, 3, 4 and 5, the absorbent unit 200 has right and left side flaps 247a and 247b laterally opposed. The side flaps are formed by folding portions of the absorbent unit toward the longitudinal axis 42, to form the respective side flaps 247a and 247b and the side edges 237a and 237b of the absorbent unit 200. Alternatively, the side flaps can be formed by joining one or more additional layers to the absorbent unit 200 in each or adjacent to each of the respective side edges 237a and 237b. In embodiments where the side flaps are formed by joining one or more additional layers to the unit absorbent, each of the additional layers may be joined with its axis laterally distally or adjacent to it. In embodiments where the portions of the absorbent unit 200 are folded inward in the lateral direction to form the side flaps 247a and 247b, the absorbent unit 200 may be folded slightly or may be folded along a portion of each of its edges laterals 237a and 237b. For example, it may be convenient to form pleats along portions of the side edges 237a and 237b in the crotch region 37 to impart a better finish to the diaper 20. Alternatively, or in addition to folding, a portion of each of the folded side flaps 247a and 247b adjacent the side edges 237a and 237b may be attached to the interior surface 202 of the absorbent unit 200 to achieve a similar result. The side flaps may overlap the absorbent core 250, i.e., the proximal edges 255a and 255b of the side flaps may extend laterally inward of the respective left side edges 257a and right 257b of the absorbent core 250. Alternatively, the flaps laterals do not overlap the absorbent core. The lateral fins are preferably permeable to water vapor, ie they are permeable at least in the crotch region 37, where they form side barriers when the diaper is used, as described in detail below. In the illustrative diaper 20 shown in Figure 1, the absorbent unit 200 extends the total length of the strips 100a and 100b of the lower canvas between the anterior waist edges 36a and 136b and the posterior waist edges 138a and 138b. This type of configuration may be convenient to minimize the amount of waste material and the difficulty associated with the manufacture of the diaper 20, especially when the method used to manufacture the diaper 20 requires the introduction of the material or materials for the absorbent unit 200 in the form of a continuous web or of several continuous frames. This configuration may also be convenient to isolate the user's skin from the lower canvas strips. Alternatively, the absorbent unit 200 may be shorter and its extension may be less than the total length of the strips of the lower canvas. This configuration may be convenient to minimize the total amount of material used and the cost of the diaper 20. Each side flap 247a and 247b is attached to the inner surface 202 of the absorbent unit 200 in adjustment zones located on the leading edge 236 and subsequent 238 or adjacent to these. For example, in the diaper 20 shown in Figure 1, the left side flap 247a is attached to the inner surface 202 of the absorbent unit 200 in the adjustment zones 251 a and 251 c, while the right side flap 247b is joined to the inner surface 202 in the adjustment zones 251 by 251 d. The adjustment zones may have equal or unequal areas. Between the adjustment zones, the proximal edges 255a and 255b of the side flaps 247a and 247b are free, ie they are not adjusted to the inner surface 202 of the absorbent unit 200. Also between the adjustment zones, each side flap preferably includes an elastic flap member extendable in the longitudinal direction attached in a position adjacent the proximal edge of the lateral flap. For example, in the diaper 20 shown in Figure 1, the elastic strands 267a and 267b are bonded adjacent the respective proximal edge 255a and 255b of the side flaps. The elastic member of the flap may be within folded hems, such as the hems 271 a and 271 b shown in Figure 4. Alternatively, the elastic member of the flap may be disposed between two layers of the absorbent or bonded unit. on a surface of the absorbent unit where it is exposed. When the elastic fin members are stretched, the proximal edges of the lateral fins may extend to the non-contracted flat length of the absorbent unit, as shown in Figure 1. When they are unstressed, they tend to contract to gather the portions of the proximal edges to which these members are attached. For example, when the illustrative diaper 20 is unstretched, as shown in Figure 14, the elastic strands 267a and 267b contract to gather the proximal edges 255a and 255b of the side flaps 247a and 247b. The forces of contraction of the elastic strands cause the anterior waist region 36 and the posterior waist region 38 to pull each other together, and thereby, the absorbent unit 200 or the entire diaper 20 flexes into a "U" shape. "whose interior is formed by the interior portions of the diaper. Since the proximal edges between the adjustment zones are free, the contraction forces of the elastic strands lift these proximal edges 255a and 255b of the side flaps 247a and 247b, away from the inner surface 202 of the absorbent unit and thus elevate the lateral fins to a position that allows them to serve as lateral barriers. The lateral spacing of the raised proximal edges is selected so that the bodily waste from the lower part of the user's torso is deposited in the space between the raised lateral fins. The width of each side flap 247a and 247b becomes the height thereof when the free portion of its proximal edge is raised and the side flap is raised. Preferably, the selected height allows the raised proximal edges 255a and 255b to conform to the folds of the user's legs forming seals that prevent the escape of body waste deposited in the diaper. As shown in Figures 15, 16 and 17, the absorbent unit 200 includes an absorbent core 250 for absorbing and retaining liquid body waste. The absorbent core 250 has a leading edge 256, a trailing edge 258, a left side edge 257a, a right side edge 257b, an inner surface 252 and an outer surface 254.

The absorbent unit 200 may include a top cover fabric disposed in a face-to-face configuration with the interior surface 252 of the absorbent core 250, in addition to a bottom cover fabric disposed in a face-to-face configuration with the exterior surface 254 of the absorbent core. 250 and the inner surfaces 102a and 102b of the respective strips 100a and 100b of the lower canvas. The upper cover fabric and the lower cover fabric can be joined to contain the absorbent core 250 therebetween, thereby forming the absorbent unit 200. For example, in the illustrative absorbent unit 200 shown in Figures 15, 16 and 17, the canvas upper cover 24 and lower cover fabric 25 are joined at side edges 237a and 237b of absorbent unit 200 or adjacent to these forming adjustment zones 29a and 29b. The upper cover canvas is permeable to water and allows liquid body waste to pass through its thickness to the absorbent core. The upper cover fabric is preferably formed of a soft material that does not irritate the wearer's skin, for example, a synthetic nonwoven fabric such as polypropylene, polyester or rayon of thermally bonded or carded filaments. The lower cover canvas may include a water permeable layer of any suitable material, for example, of the same material used for the upper cover canvas. A portion or the total of any of the cover canvases, top or bottom, may be permeable to water vapor, i.e., permeable. Alternatively or additionally, the lower cover canvas may include a liquid impermeable layer formed of a suitable material, for example, a polyethylene or other polyolefin film, a microporous ventilated film, a hydrophobic nonwoven fabric or a film formed by layers coextruded polyolefins. For example, a suitable co-extruded film is that distributed by Clopay Plástic Products Co. of Mason, Ohio, USA with the designation M18-327. A lower multilayer cover web, such as a sheet of a film and a nonwoven fabric may also be suitable and may be oriented with the nonwoven fabric arranged externally to provide the feel and appearance of an outermost layer similar to a non-woven fabric. genre, with the non-woven fabric disposed internally to separate the film from the wearer's skin, or with the non-woven fabrics arranged both externally and internally. The upper cover canvas and the lower cover canvas may have the same length and width. Alternatively, one or more of the edges of one of the cover canvases may be left distal to the respective edge or edges of the other cover canvas. For example, the upper cover canvas may have the longitudinal length necessary only to cover the absorbent core and to join the lower cover fabric, adjacent to the leading or trailing edge of the absorbent core, while the lower cover fabric may extend longitudinally further beyond the upper covering canvas, towards the edges of the waist of the strips of the lower canvas or adjacent to them. This longitudinally extending lower cover web can serve to isolate the user's skin from a portion of the lower canvas strips when, for example, when using the diaper, the contact between the skin and the film of the lower canvas can be uncomfortable. Similarly, the upper cover fabric may have the required lateral extent only to cover the absorbent core, or to join the lower cover fabric adjacent the left or right lateral edge of the absorbent core. The lower cover canvas may extend laterally beyond the upper cover canvas. For example, in the illustrative absorbent unit 200 shown in Figure 4, the upper cover fabric 24 extends laterally just beyond the side edges 257a and 257b of the absorbent core 250 and is attached to the lower cover fabric 25 in FIG. this area. The lower cover fabric 25 in this illustrative absorbent unit extends laterally beyond the upper cover fabric 24 and is folded to form the side flaps 247a and 247b. The absorbent unit and the lower canvas strips may be bonded together at any part or all of the length of the absorbent unit. Preferably, the absorbent unit is attached on its outer surface to the strips of the lower canvas in the adjustment zones 220a and 220b extending in the longitudinal direction and opposite laterally shown in Figures 2, 3, 4, 5, 13, 15, 16, 17 and 19. The portions of the strips of the lower canvas that lie outside this joining pattern are not limited by the attachment to the absorbent unit and, therefore, remain extensible. For example, a relatively narrow longitudinally extending adjustment zone, such as, for example, the left adjustment zone 220a, allows the greater part of the width of the strip of the left lower canvas 100a to be freely extended and thus allows extension of the strip of the lower left panel 100a in the lateral direction. Within the range of the adjustment zones, the absorbent unit may be attached to the strips of the lower canvas continuously or intermittently. For example, a film of an adhesive can be applied continuously over the entire area of the adjustment zones and then used to continuously join the absorbent unit to the strips of the lower canvas. As an alternative example, an adhesive can be applied in discontinuous form within the boundaries of the adjustment zones and within them, in the form of dots, strips, beads, spirals, etc., and then used to join the absorbent unit to the strips of the lower canvas. The absorbent core may be attached to the lower cover fabric anywhere or in the entire area of the absorbent core. Preferably, the absorbent unit is attached by its outer surface to the lower cover fabric in a pattern of cruciform union, that is, in a union pattern that is formed or arranged in the form of a cross or "+". The cruciform union pattern can be contiguous, that is, all its portions can be touched or connected throughout the pattern in an uninterrupted sequence or it can have missing portions and therefore lack of continuity but still be organized so that the shape of the pattern total is cruciform. An illustrative cruciform and contiguous joint pattern 210 is shown in Figures 15, 16 and 17. When an adhesive is used for bonding, the amount required in a cruciform joint pattern may be less than that required in a bonding pattern. extensive. In addition, the portions of the lower cover canvas that lie outside this cruciform joining pattern are not limited by the attachment to the absorbent core and, therefore, remain extensible. In particular, a relatively narrow portion 212 of a cruciform joining pattern 210, extending in the longitudinal direction, such as that shown in Figures 15 and 17, leaves most of the width of the lower covering web 25 of the region. of the anterior waist 36 and of the rear waist region 38 freely extensible and, thus, allows in these regions the extension of the lower cover canvas 25 in the lateral direction. A relatively wide extended portion in lateral direction 214 of a cruciform joining pattern 210 such as that shown in Figures 15 and 16 prevents the portion of the lower cover canvas 25 in the crotch region 37 where the core is attached. absorber 250 deviates from the absorbent core 250 in that region and, thereby, contributes to the high lateral fins fulfilling their function. For example, if the lower cover fabric in the crotch region 37 could be deflected freely laterally, the raised side flaps 247a and 247b could be distorted, no longer effective to stay in contact with the body, or they could be placed in wrong Within the reach of the cruciform joint pattern, the absorbent core may be attached to the lower cover fabric continuously or intermittently. By For example, a film of an adhesive can be applied continuously over the entire area of the cruciform joint pattern and then used to continuously bond the absorbent core to the lower cover canvas. As an alternative example, an adhesive can be applied discontinuously at the boundaries of the cruciform joint pattern and within them, in the form of dots, strips, beads, spirals, etc., and then used to join the absorbent core to the canvas of lower coverage. The absorbent core 250 includes a storage component 272 for absorbing and retaining liquid body waste. Known materials suitable for the storage component of the absorbent core include cellulose fibers in the form of ground wood pulp, commonly known as "air felt", layers or canvases of synthetic or natural fibrous material or materials, one or more polymers superabsorbents, etc. These absorbent materials can be used separately or in combination. Many known materials can be used in the form of separate or loose elements, that is, in the form of fibers, granules, particles, and the like. This different form of absorbent material can be immobilized by means of an adhesive that joins the different pieces to form a coherent layer, or that joins the different pieces to a layer of substrate, or that joins the different pieces together and to the layer of the substrate to the Same time. The absorbent core may include an acquisition component in addition to one or more storage components. The absorbent component of the absorbent core serves to acquire the deposited liquid body waste and transfer it to the storage component of the absorbent core. Any porous absorbent material that permeans and separates liquid body wastes from the component or storage components can be used to make the absorption component. The preferred materials for making the absorption component they include synthetic fiber materials, open cell polymeric foam materials, fibrous materials of non-woven fabrics, cellulosic materials of non-woven fabrics and various combinations of cellulosic and synthetic materials of non-woven fabrics. For example, the absorption component can be made with one or more wefts of non-woven fabric of synthetic fibers, including polyester, polypropylene and polyethylene, natural fibers including cotton and cellulose, mixtures of those fibers or equivalent materials or combinations of materials. Examples of such absorption materials are described in more detail in U.S. Pat. no. 4,950,264 issued to Osborn on August 21, 1990. High non-woven fabric absorption materials suitable for use in the absorption component of the present invention can be obtained from Polymer Group, Inc., (PGI), 450 N.E. Blvd, Landisville, New Jersey 08326, USA, identified with the material code 98920. In Figures 15, 16 and 17, this absorption component of the absorbent core 290 is shown overlapped to the storage component of the absorbent core 272. A separation web 292 of, for example, a fabric or a non-woven fabric material may be disposed between the storage component of the absorbent core 272 and the absorbent component of the absorbent core 290 to ensure that no portion of the gel formed by a superabsorbent polymer comes in contact with the user's skin. This separation web 292 may extend laterally beyond the side edges 257a and 257b of the absorbent core 250, and the upper cover web 24 may be joined to the separation web 292. In this distribution, the liquid body waste deposited on the web of The top cover 24 passes through the thickness of the latter so that the absorbent component of the absorbent core 290 absorbs them and then passes through the thickness of the separation canvas 292 completely or partially so that the storage component of the core absorbent 272 absorb and retain them. As shown in Figure 18, in some illustrative embodiments, a storage component of the absorbent core 272 may include the distinct shape of an absorbent material immobilized in the pouches formed of a layer of a thermoplastic material, such as a hot-melt adhesive that is in intermittent contact and adheres to a substrate canvas while deviating from the substrate canvas in the bags. Absorbent core components that have such structures and are suitable for storing liquid body wastes are described in U.S. patent applications. co-pending and assigned jointly. 10 / 776,839 and 10 / 776,851, both filed on February 1, 2004 in the name of Ehrnsperger et al. A storage component of the illustrative absorbent core 272 having that structure is shown in Figure 18. In this storage component of the absorbent core 272, the particles 270 of a superabsorbent polymer are contained within the pockets 280 formed by a layer 275 of a thermoplastic material. The storage component of the absorbent core can include particles of a superabsorbent polymer and air felt and the two materials can be inside pouches formed by the layer of the thermoplastic material. Alternatively, as shown in Figure 18, a storage component of the illustrative absorbent core may not contain air felt and therefore may be relatively thinner and more flexible to improve user comfort. In addition, the particles of the superabsorbent polymer can be immobilized more easily in the absence of the air felt. As shown in Figure 18, the layer 275 of the thermoplastic material intermittently contacts and adheres to a substrate canvas 274 in the adjustment areas 282. Between the adjustment areas 282, the layer 275 deviates from the substrate canvas. 274 to form the bags 280. Layer 275 may have the form a fiber canvas of the thermoplastic material through which the body waste can pass so that the particles 270 of the superabsorbent polymer absorb them. In Figure 18 a single thermoplastic layer cover sheet 276 is shown on layer 275 of the thermoplastic material. Alternatively, this cover sheet 276 may be omitted. In another alternative shown in Figure 18, but without the cover layer of thermoplastic layer 276, the two storage components of the absorbent core may be overlapped with a storage component of the inverted absorbent core, so that the respective substrate canvases are distally opposed to each other. In that combination of storage components of the absorbent core, one or both of the distally opposed substrates may respectively serve as one or both of the upper and lower cover canvases of the absorbent unit. Alternatively, the absorbent unit may include a separate bottom cover fabric, disposed between the absorbent core and the interior surface of the bottom sheet and / or a separate top cover fabric, disposed within the interior of the absorbent core. The absorbent unit may include an additional bottom sheet of a film or other waterproof material to improve protection against leakage. For example, as shown in Figure 19, an additional bottom sheet 226 of a film or other water impervious material can be fitted within the absorbent unit between the lower cover fabric 25 and the absorbent core 250. Alternatively, the canvas of additional base can be adjusted to the absorbent unit on the outside of the lower cover canvas. This additional base cloth may extend laterally to a smaller distance from the left side edge 237a, and from the right side edge 237b or both edges of the absorbent unit 200, as shown in Figure 19, or it may extend laterally to overlap to one or both side edges of said unit. When said additional base canvas is joined within the absorbent unit between the lower cover canvas and the absorbent core, the additional base canvas can be joined to the lower cover canvas in a cruciform joining pattern similar to that shown in Figure 15, thus leaving the portions of the lower cover canvas that are outside the cruciform joint pattern unattached to the additional base canvas and allowing these portions to be extensible. For example, a laterally extending portion 214 of said cruciform joint pattern is shown in Figure 19. Alternatively or additionally, the additional base canvas of such an embodiment may be attached by said cruciform bonding pattern to the absorbent core, thereby allowing that portions of the additional base canvas that lie outside the cruciform joint pattern are not attached by attachment to the absorbent core and also that these portions are extensible. In such an embodiment, although the additional base canvas is attached to the lower cover fabric in a non-cruciform joining pattern, the lower cover fabric is not indirectly limited by the absorbent core and, therefore, may be extensible. Description of the article form The finished diaper can have a generally rectangular shape, like that of the illustrative diaper 20 shown in Figures 1 and 2. This generally rectangular configuration can be convenient to minimize the amount of waste material and the difficulty associated with the manufacture of the diaper 20. Alternatively, the diaper may have side edges 137a and 137b that are not straight but curved and / or cut-away, whereby it imparts to the diaper 20 a shape which in plan view is that of an hourglass or an "I". This non-rectangular configuration can be convenient to impart to the diaper 20 the made-to-measure look when used. This non-rectangular configuration may also be convenient to give the impression that the diaper 20 will be comfortable when placed between a user's legs. There are several ways to give a non-rectangular diaper configuration. For example, the laterally distal portions of the diaper can be removed to make its lateral dimension at and adjacent the lateral axis 44 smaller than its lateral dimension at and adjacent to the anterior waist edge 136 and smaller than its lateral dimension at and adjacent the trailing waist edge 138, that is, to make the diaper narrower in the crotch region 37 than at the waist edges. An illustrative form of said non-rectangular configuration of the diaper is shown in Figure 20. As shown in this figure, the portions of the strips 100a and 100b of the lower canvas can be removed to form lateral laterally opposed notches 111a and 111b, while the strips of the lower canvas are left in a continuous arrangement in a longitudinal fashion. Alternatively, a portion of each of the side edges 137a and 137b may be bent laterally inwardly to form a non-rectangular configuration of the diaper. For example, as shown in Figures 21, 22 and 23, the laterally opposite portions 107a and 107b of the strips 100a and 100b of the lower canvas in the crotch region 37 can be folded laterally inwardly to overlap the respective ones. side flaps 247a and 247b and can be attached to the side flaps, for example, in the respective adjustment zones 109a and 109b. Preferably, each of the laterally bent opposite portions 107a and 107b laterally extends only a portion of the path from the respective lateral edge 237a or 237b of the absorbent unit 200 to the longitudinal axis 42, thereby exposing the respective exposed portions 207a and 207b of the lateral fins, which form side barriers when the diaper is used, according to described above, especially when the lateral barriers are permeable. As another alternative, the strips of the lower canvas can be arranged discontinuously and in the longitudinal direction to form a diaper configuration of non-rectangular shape. For example, as shown in Figure 24, the strips of the lower canvas may be separated into a left strip of the previous lower canvas 100a, a left strip of the lower rear canvas 100c, a right strip of the previous lower canvas 100b, and a strip right of the lower backsheet 100d, and each of these strips of the lower canvas may extend laterally beyond the side edges 237a and 237b of the absorbent unit 200, thus imparting the diaper 20 an "I" shape. The exhibits of all the patents, the patent applications and the patents granted on the basis of them, in addition to all the corresponding published foreign patent applications, and all the publications listed and / or cited in this description are hereby incorporated into the present as a reference. Specifically, it is not admitted that any of the documents or any combination of documents incorporated herein by reference, show or expose the present invention. Although particular embodiments or individual features of the present invention have been illustrated and described, it will be obvious to those skilled in the industry that various other changes and modifications may be made thereto without departing from the spirit and scope of the invention. Furthermore, it should be evident that it is possible to perform all combinations of these embodiments and features and that they may result in preferred embodiments of the invention. Therefore, the following claims attempt to cover all changes and modifications that are within the scope of this invention.

Claims (9)

1. A disposable diaper having an anterior waist region, a posterior waist region and a crotch region between the waist regions; the diaper comprises: An absorbent unit having an inner surface and an outer surface and lateral fins that extend longitudinally and are laterally opposite; each side flap has longitudinally opposite ends and a longitudinally extending proximal edge; each side flap is attached adjacent its ends to the inner surface of the absorbent unit and has a longitudinally extending elastic gathering member attached adjacent its proximal edge such that when it relaxes, the elastic shirring member contracts and lift the proximal edge away from the inner surface of the absorbent unit, thereby lifting the side flap to form a lateral barrier; characterized in that it has two strips of the bottom sheet extending longitudinally opposite one another which are attached to the outer surface of the absorbent unit, wherein at least a portion of the absorbent unit between the strips of the bottom sheet or at least one of the strips strips of the lower canvas is extensible in lateral direction.

The disposable diaper according to claim 1, further characterized in that the extensible portion comprises a weft material that includes at least two distinct altered regions extending in the lateral direction, each of which contains a pattern of ridges and valleys. alternating ones oriented in generally longitudinal direction generated by a deformation of the weft material and also contains an unaltered region located between the altered regions, so that the The deformed weft material may extend in a lateral direction to a given extent by applying a force relatively less than that necessary to extend the same weft material in the same direction to the same extent as before the deformation.

3. The disposable diaper according to any of the preceding claims, further characterized in that at least a portion of one of the waist regions extends laterally to a greater degree than at least a portion of the crotch region in such a way that a The lateral extension of one of the waist regions or a waist region and the crotch region imparts an hourglass shape to the disposable diaper.

The disposable diaper according to any of the preceding claims, further characterized in that the absorbent unit includes an absorbent core and a lower cover fabric having at least one portion that is disposed on the outside of the absorbent core and laterally opposed portions. of the lower cover fabric which are folded laterally inwards to form the respective lateral fins.

The disposable diaper according to any of the preceding claims, further characterized in that the strips of the lower canvas are attached to the absorbent unit in adjustment zones extending in the longitudinal direction and opposing laterally.

The disposable diaper according to any of the preceding claims, further characterized in that it comprises at least one fastening element for securing both the anterior waist region and the posterior waist region in order to surround the waist and legs of a user, wherein the clamping element is adapted to open and re-clamp.

7. The disposable diaper according to claim 6, further characterized in that the fastening element includes an adherent fastening element.

The disposable diaper according to any of the preceding claims, further characterized in that it comprises adherent fastening elements disposed on the inner surface of the disposable diaper and on an outer surface of the disposable diaper so that the anterior waist region can be secured over the disposable diaper. the posterior waist region or the posterior waist region may alternatively be secured over the anterior waist region to surround a user's waist and leg.

9. The disposable diaper according to any of the preceding claims, further characterized in that the absorbent unit comprises a storage component of the absorbent core that does not contain air felt.