WO1998037840A1

WO1998037840A1 - Absorbent article with improved shape stability

Info

Publication number: WO1998037840A1
Application number: PCT/SE1998/000235
Authority: WO
Inventors: Anders Gustafsson; Peter Rönnberg; Eva Fransson
Original assignee: Sca Hygiene Products Ab
Priority date: 1997-02-28
Filing date: 1998-02-12
Publication date: 1998-09-03
Also published as: ZA981621B; CO5040076A1; SE9700732D0; SE508538C2; SE9700732L

Abstract

An absorbent article, such as a diaper, an incontinence protector or a sanitary towel, with an essentially elongate shape and with a longitudinal direction and a transverse direction, and comprising an absorption body (4) enclosed between a liquid-permeable cover layer (2) and a liquid-impermeable cover layer (3), and having at least one elastic barrier (31, 32), the elastic barrier (31, 32) comprising a piece of material (9) which can be raised from the liquid-permeable cover layer (2), and an elastic member (19, 20) which is arranged pretensioned. A flexurally rigid shaping element (22) curved in an arch shape is arranged between two edges (7, 8) of the article, the shaping element (22) counteracting the contracting force occurring in the raisable piece of material (9) on account of the pretensioning of the elastic member (19, 20), as a result of which the article has a barrier (31, 32) raised from the liquid-permeable cover layer (2).

Description

ABSORBENT ARTICLE WITH IMPROVED SHAPE STABILITY

TECHNICAL FIELD:

The invention relates to an absorbent article, such as a diaper, an incontinence protector or a sanitary towel, with an essentially elongate shape and with a longitudinal direction and a transverse direction, and comprising an absorption body enclosed between a liquid-permeable cover layer and a liquid-impermeable cover layer, and also having two longitudinal side edges, two transverse end edges, and at least one elastic barrier arranged along one edge of the article, the elastic barrier comprising a piece of material which can be raised from the liquid-permeable cover layer, and an elastic member which is arranged pretensioned in the long direction of the edge.

BACKGROUNDs

A major problem in connection with articles intended to absorb bodily excretions such as urine, faeces or blood, is that the liquid runs out past the edges of the article. In order to counter such leakage from the edges, it has long been customary to provide absorbent articles of this type with elastic edge barriers. The elastic edge barriers are generally obtained by means of elastic members arranged along the edge portions of the article.

The barrier effect is then achieved in two basically different ways. Elastic edge barriers of a first type are intended to form tight elastic seals, for example around the user's legs and waist. Such elastic edge barriers are present on diapers or incontinence protectors which are designed as absorbent underpants or which can be secured together so that when they are used they assume a shape similar to pants. The elastic edges in this case function as elastic cuffs around the user's legs and/or waist. Because the elastic members are pretensioned along the edges of the article, or drawn tight when the article is put on, the-edge portions of the article are held tightly against the user's body.

Elastic barriers of a second type form liquid obstructors raised from the surface of the article. Raised barriers are present, for example, in combination with gasketing edge barriers on diapers and the like for the purpose of controlling the flow of liquid in the article and for increasing the security against leakage. However, a large group of absorbent articles, including certain types of diapers and incontinence protectors as well as sanitary towels, do not have gasketing elastic edge barriers. The articles concerned do not have means for fastening them into a shape similar to pants and it is therefore not possible to produce gasketing elastic seals. Instead, the articles are usually comparatively smaller than the trunk- enclosing diapers and incontinence protectors and are designed to be fitted and supported inside the user's underpants or inside pants or tie-ons specially adapted for the purpose. In order to prevent flow of liquid out past the edges of the article, elevated elastic barriers are often arranged along the edges of the article.

An example of an absorbent article intended to be worn inside a pair of underpants is disclosed in European Patent 0,091,412. The known article is of a conventional type, with an absorption body enclosed in a cover. In order to create raised edge barriers, the article is provided with longitudinal elastic members, arranged at a distance from the absorption body in side flaps formed by cover material. Although such edge leakage barriers do increase security against leakage, there is still a need for improved edge leakage barriers for absorbent articles intended to be supported by outer pants or tie-ons. It has in fact been found that it is difficult to ensure that the elastic barriers are kept lifted during use. Moreover, there is a risk that the elastic members, instead of raising the elastic barriers, contract so much that the article crumples up and loses its shape. There is then a risk of folds or wrinkles forming and of these chafing the user's skin. Another significant risk is that of the article being contracted so much that its ability to take up the excreted bodily fluid is greatly reduced. The risk of considerable deformation of the article is especially great when the article has absorbed bodily fluid. This is because a wet absorbent structure generally has considerably less shape stability and stiffness than in its dry state. Moreover, during use, the article is exposed to the mechanical effects of the forces which arise when the user moves, for example when the user is walking.

BRIEF DESCRIPTION OF THE INVENTION:

With the present invention, however, an absorbent article is provided which is of the type mentioned at the outset, and in which article the problems associated with the previously known articles of this kind have been substantially eliminated.

An article designed according to the invention is distinguished primarily by the fact that a flexurally rigid shaping element is arranged between two edges of the article, alongside the elastic barrier and with a main direction of extension coinciding with the direction of extension of the elastic barrier, the shaping element having an arched portion between the edges, which portion is curved in the direction away from the liquid-permeable cover layer and counteracts the contracting force arising in the raisable piece of material on account of the pretensioning of the elastic member, whereby the article has a barrier extending along the edge and raised from the liquid-permeable cover layer.

Further embodiments and features will be evident from the attached patent claims.

DETAILED DESCRIPTION OF THE INVENTION:

In order to achieve a full barrier effect with a barrier which has been lifted up with the aid of an elastic member pulling together the material of the barrier, the elastic member needs to be tensioned. According to the invention, this is achieved using a shaping element which counteracts the contracting force of the elastic member. A barrier with very good ability to adapt to changes in the stretching and contracting forces which occur in the elastic member during use is obtained if the raisable piece of material in the barrier has, before contraction, at least the same length as the shaping element in the direction of extension of the barrier.

The shaping element must have high flexural strength so that the tensile forces from the elastic member do not give rise to breaks or folds in the shaping element. Sufficient flexural resistance can be achieved, for example, by laminating a plurality of components whose combined rigidity is sufficiently high, or by using a separate rigidity-enhancing component, such as an insert made of flexurally rigid plastic or metal.

It is possible to use stiffening elements of extremely high rigidity. Such a stiffening element can be made, for example, of any type of metal or hard plastic which remains essentially unaffected by the tensile forces from the elastic member and by the forces which occur during use of the article. Such an extremely rigid stiffening element must be preformed in such a way that, upon manufacture of the article, it has been given a curvature which approximately corresponds to the curvature of the user's body in the region in question.

However, although a static shaping element affords a satisfactory function, a shaping element with a certain flexibility is preferable, for several reasons. A flexible shaping element can, for example, consist of or comprise a flexurally rigid but flexible rail, rod, pipe, or similar elongate body made of plastic, metal, or the like. Several such shaping elements can of course be included in one and the same article, for example several flexurally rigid bands or rods arranged in parallel, crossed, or angled in relation to each other.

The material in the shaping element should include at least one component which, during use of the absorbent article, will remain essentially unaffected in terms of the properties which are important to its function as a shaping element. These include the flexural rigidity, flexural elasticity and mechanical stability of the shaping element. It is therefore not appropriate to use shaping elements which consist entirely of a material which loses its rigidity when it becomes wet, or through mechanical action during use. This does not mean that the shaping element cannot consist of or comprise absorbent material. For example, a flexurally rigid, flexurally elastic shaping element of plastic can be laminated with layers of absorbent fibre material or can have a portion which is absorbent and which softens upon absorption. In the latter case, however, the shaping element must retain sufficient rigidity in the direction of extension which coincides with the elastic barrier. An example of one such shaping element is an elongate shaping element which is intended to counteract the contracting force in elastic barriers arranged along the side edges of an absorbent article. Such a shaping element can have longitudinal absorbent portions, on condition that a contiguous longitudinal portion with sufficient rigidity remains even after wetting.

Flexible, flexurally elastic, but rigid, shaping elements can be manufactured in a flat form and can be given a desired curvature in conjunction with the shaping element being secured to the article. The tensile force in the elastic member or members intended to cooperate with the shaping element should in this case be balanced against the flexural rigidity of the shaping element, so that the shaping element, by pretensioning of the elastic members, is given a curvature which approximates to the curvature of the lower part of the user's trunk. The shaping element can be arranged on or in the article by the manufacturer. Alternatively, the shaping element is arranged by the user, or his/her carer, at the time of use. This provides the advantage of the article being able to be packed in an essentially flat configuration, or folded up, a fact which increases its manageability and saves space and packaging material. A further possibility is that only part of the shaping element is secured to the article, so that the article can be packed essentially flat, and the shaping element is clamped inside the article only at the time of use.

In addition to raising the elastic edge barriers, the shaping element according to the invention curves the article in the direction away from the user. In this way, a space is formed between the user's body and the article, which space permits exchange of air and in addition can serve as a liquid-accommodating reservoir for bodily fluid which has not yet managed to be absorbed into the article. It is of course possible to create raised barriers in accordance with the invention both along the side edges of an absorbent- article and on one or both end edges.

The flexural resistance of the shaping element should be adapted so that it can be curved by the elastic members into a shape which approximates to the shape which the absorbent article is expected to have during use. When using a flexurally elastic shaping element, this is takes the form, after pretensioning of the elastic members, of an arched spring element extending between two edges of the article. As a result of the flexural elasticity and resilience of the shaping element, the shape of the article is adapted during use to the body position and movements of the user. The rigidity needed to achieve a certain shape of the absorbent article cannot be stated exactly since it is dependent on a number of different factors. As the skilled person will immediately appreciate, the material of the shaping element, as well as its configuration, material thickness, size, etc., is of importance, as is the choice of material and configuration of the elastic members. Of course, the size of the expected category of user of a given absorbent article also comes into play, since the shape of the user's body determines the ideal curvature of the article. For example, the curvature from abdomen to buttocks is greater in a child than it is in an adult user of an absorbent article.

The absorbent article can be provided with securing members for securing the article in the user's underpants, in a tie-on, or the like. For example, securing members in the form of self-adhesive material can be arranged on the outside of the article, i.e. on that surface which is intended to be directed towards the underpants during use. Other suitable securing members, which can be used alone, or together with self-adhesive material or hook-and-loop surfaces on the outside of the article, are securing flaps arranged on the side edges of the article. Such securing flaps extend along at least a portion of each side edge of the article, the securing flaps being intended, during use, to be folded around the leg edges of the user's underpants and being provided with means for securing the flaps on the outside of the underpants. Suitable means for securing the flaps on the outside of the underpants are, for example, adhesive surfaces, hook-and-loop surfaces, snap fasteners, or the like. It is also possible to use securing flaps of the type which automatically clamp around the side edges of the underpants. Examples of such securing flaps are given in WO 92/07537 and WO 92/07536, which publications describe securing flaps which are arranged on the underside of an absorbent article, with the free ends of the flaps being directed in towards the longitudinal centre line of the article. Such securing flaps function especially well in combination with a flexurally rigid article which is curved lengthways, since the curvature contributes to holding the securing flaps pressed against the underside of the article.

BRIEF DESCRIPTION OF THE FIGURES:

The invention will be described in greater detail below, with reference to the illustrative embodiments which are shown in the attached drawings, where:

Fig. 1 shows a diaper according to a first embodiment of the invention, viewed from the side which, during use, is directed towards the user; Fig. 2 shows an incontinence protector according to the invention, viewed from the side which, during use, is directed towards the user;

Figure 3 is a section along the line III-III through the incontinence protector in Figure 2;

Figure 4 is a section along the line IV-IV through the incontinence protector in Figure 2 ;

Figure 5 shows a sanitary towel according to the invention, viewed from that side which, during use, is directed towards the user, and

Figures 6 to 9 show different designs of shaping elements according to the invention.

DETAILED DESCRIPTION OF EMBODIMENTS:

The diaper 1 shown in Figure 1 comprises an absorption body 4 enclosed in a cover 2, 3. The cover 2, 3 consists of a liquid-permeable cover layer 2 and a liquid-impermeable cover layer 3. The cover layers 2, 3 are connected to each other around the edges 5 - 8 of the diaper, for example by adhesive bonding, stitching or welding with heat or ultrasound.

The liquid-permeable cover layer 2 expediently consists of a soft, skin-compatible and flexible material of the type which is customarily used as surface material for absorbent articles. Examples of such materials are perforated plastic films, nonwoven textiles or materials, nets of textile or plastic, produced by knitting, crocheting, braiding, casting, or the like, and of course conventional woven textile materials. The liquid-permeable cover layer 2 can be made up of a single material layer or consist of two or more layers -of identical or different materials.

The liquid-impermeable cover layer 3 can be of any soft and conformable material with sufficient resistance to liquid penetration. Examples of suitable materials are thin, flexible plastic films, dense nonwoven materials, hydrophobicized textile materials or paper layers, liquid- permeable materials with a liquid-impermeable coating, or the like.

The absorption body 4 can also be of any type suitable for the purpose. Thus, the absorption body 4 can be made up of one or more layers of absorbent fibres such as cellulose fluff pulp, rayon, cotton or the like, and tissue material, nonwoven material, foam or other absorbent or nonabsorbent components .

In order to increase the absorption capacity, the absorption body 4 can contain so-called superabsorbents, which are polymer materials, usually present in the form of particles, flakes, fibres, or the like, and with the ability to absorb several times their own weight of bodily fluid and form an aqueous gel. Superabsorbents can be present as one or more layers or areas in the absorption body 4 or can be mixed with other absorption materials, such as cellulose fluff pulp or absorbent fibre wadding of another type. Moreover, the superabsorbents can of course be arranged in a nonabsorbent supporting structure, for example a fibre layer of nonabsorbent fibres.

Arranged outside the liquid-permeable cover layer 2 is a barrier layer 9. The barrier layer 9 is intended to be directed towards the user when the diaper is in use and is secured to the liquid-permeable cover layer 2 along the edges 5-8 of the diaper, using one of the above-mentioned joining methods. The barrier layer 9 also has an opening 10 through which bodily fluid can pass inwards to the liquid- permeable cover layer 2 and onwards to the absorption body 4 of the diaper. The opening 10 is comparatively large and covers most of that surface of the diaper which, during use, is intended to be directed towards the user.

The material in the barrier layer 9 can comprise one or more layers of nonwoven, plastic film, paper, woven or knitted or cast material. The barrier layer 9 is advantageously liquid-impermeable, or at least hydrophobic, so that it resists liquid penetration. Moreover, the barrier layer 9 is preferably gas-permeable and vapour- permeable, since the diaper is in this way able to breathe, a fact which contributes to increased wear comfort.

The diaper 1 has an essentially rectangular shape, with two longitudinal side edges 5, 6 and two transverse end edges 1 , 8. The side edges 5, 6 run together with the end edges 7, 8, as a result of which the diaper has four corners 11- 14. The diaper can also be divided in the longitudinal direction according to the intended positioning in relation to the user's body. In this case the diaper has a crotch portion 15, which is that part of the diaper which, during use, is intended to be arranged in the crotch region, between the user's legs, and two end portions 16, 17 which, during use, are intended to be directed forwards and, respectively, rearwards on the user.

By making an opening 10 in the barrier layer 9, a liquid- accommodating pocket 18 is formed between the barrier layer 9 and the liquid-permeable cover layer 2, along the edges of the diaper. An elastic member 19, 20 running in the longitudinal direction of the diaper is arranged between a corner 11, 12 at one end portion 16 and the corresponding corner 13, 14 at the other end portion 17 on both sides of the opening 10. The elastic members 19, 20 are secured to the barrier layer 9 by means of adhesive bonding, welding, stitching, or in any other suitable manner, and can be arranged on the inside or outside of the layer 9 or between two layers included in the layer 9. The inside in this context is that surface of the barrier layer 9 which is directed towards the liquid-permeable cover layer 2, while the outside is that surface which is directed away from the liquid-permeable cover layer 2.

The elastic members 19, 20 used can be, for example, elastic filaments, bands, or the like, consisting of rubber, foam material, elastic nonwoven material, or laminates in which at least one incorporated component is elastic. In addition, the barrier layer 9 can itself comprise elastic material, in which case special elastic members 19, 20 are not necessary.

Moreover, a shaping element 22 in the form of two flexurally rigid parts, for example rods, pipes, bands, or the like, is arranged between end portions 16, 17 of the diaper. A first part 23 of the shaping element 22 extends from a corner 11, at a first end portion 16 of the diaper, to the diagonally opposite corner 14 at the other end portion 17 of the diaper. The second part of the shaping element 22 is arranged between the two remaining corners 12, 13 of the diaper. In this way, the two parts 23, 24 of the shaping element 22 cross each other at the crotch portion 15 of the diaper.

In the diaper 1 shown in Figure 1, the two parts 23, 24 of the shaping element 22 cross centrally at the crotch portion 15. Such a design has the advantage that the shaping element 22 can serve as barriers against urine and faeces mixing on the surface of the diaper. Keeping urine and faeces separate prevents bacteria from the faeces breaking down the urea in the urine, as a result of which there is less risk of bad smell and skin irritation caused by the products of decomposition of the urine. The shaping element 22 also constitutes an extra barrier against uncontrolled flow of liquid across the surface of the diaper.

The shaping element 22 is held in the diaper 1 by means of the fact that the ends 25-28 of its two parts 23, 24 are inserted under the barrier layer 9 at the corners 11-14 of the diaper. The ends 25-28 of the shaping element 22 are thus introduced into the pocket 18 which is formed between the barrier layer 9 and the liquid-permeable cover layer 2.

The diaper can be supplied to the user in the state illustrated, with the shaping element arranged in the pocket 18 under the barrier layer 9. However, the shaping element 22 can alternatively be supplied unassembled, in which case the user or his/her carer arranges the shaping element 22, in the manner shown, when the diaper is being put on.

By simple manipulation of both parts 23, 24 of the shaping element 22, it is possible to control where the parts 23, 24 will cross each other on the diaper. Thus, the user himself/herself can determine whether the crossover 30 will be moved forwards or rearwards on the diaper. The position of the crossover 30 can be determined on the basis of what the user feels will be most comfortable and what is judged to give the best shape to the diaper or the best function.

The object of arranging a rigid shaping element 22 inside the diaper 1 is to produce a counter force to the elastic members 19, 20 arranged on the barrier layer 9 in a pretensioned manner. In this way, the diaper is given the desired, curved shape in the longitudinal direction, at the same time as the edges around the opening 10 in the barrier layer 9 are -lifted up from the liquid-permeable cover layer 2 by the tensile force in the elastic members 19, 20. In this way, raised elastic barriers 31, 32 are formed along the side edges 5, 6 of the diaper.

In a conventional diaper of the type which is supported by a pair of underpants, or a tie-on, where there is no counter force to the elastic members, there is a considerable risk of the elastic members being drawn together so much that the diaper crumples up into a shape which is disadvantageous both in terms of fit and with respect to absorption. Another disadvantage of these diapers is that those portions of the barrier layer 9 which are provided with elastic are folded in across the liquid- permeable surface layer 2 and come to bear against its surface instead of forming raised barriers. When this happens, the surface area available for receiving liquid is reduced, and there is an obvious risk of liquid running out along the outside of the barrier layer. Because a diaper without a shaping element 22 lacks shape stability, the elastic portions of the barrier layer 9 can also be folded out towards the side edges 5, 6 of the diaper, level with the liquid-permeable cover layer, as a result of which the risk of leakage out past the side edges obviously increases radically.

The shaping element 22 counteracts undesired deformation of the diaper 1 and keeps it stretched both in the longitudinal direction and in the transverse direction. By choosing a shaping element 22 made of a material which is flexurally rigid, but which still has certain pliability under the forces which it is subjected to by the elastic members 19, 20 and during use, a diaper is obtained which, during use, continuously adapts to the movements of the user's body and to the consequent changes in the tension of the elastic members. In this way, the raised barriers 31, 32 are at al-1 times held in contact with the user's body and seal against leakage past the side edges 5, 6 of the diaper. According to the invention, an elastic edge leakage protection is thus obtained which much resembles the tight seal which, in conventional absorbent articles, can only be produced by the article being secured, in the manner of pants, around the user's waist and legs, or suspended from a strap, or a girdle.

It is not possible to give exact values regarding the rigidity of the shaping element 22 since this has to be weighed against the tensile force of the elastic members 19, 20 such that a desired shape and barrier effect are obtained. It is, however, expedient to choose a material which has flexural elasticity, so that the shaping element 22 at all times adapts to the changes which occur in the shape of the diaper and to changes in the extension of the elastic members 19, 20. It is also important that the shaping element 22 does not crack, fold or break in response to the forces to which it is subjected during use. The shaping element 22 should be of a material which is essentially unaffected by moisture or liquid in the diaper. It is particularly important here that the shaping element 22 is wet-resistant in terms of rigidity, pliability and other parameters which influence its shape and function as the force-accommodating member of the diaper.

The incontinence protector 200 shown in Figures 2 to 4 has a liquid-permeable cover layer 202, a liquid-impermeable cover layer 203, and an absorption body 204 enclosed between the cover layers 202, 203. The liquid-permeable cover layer 202 consists, for example, of a layer of nonwoven material or of perforated plastic film, net material, or the like. The liquid-impermeable cover layer 203 can consist of a liquid-impermeable plastic film, a nonwoven layer which has been coated with a liquid- obstructing material, or some other flexible material layer which has the ability to resist liquid penetration. It is generally an advantage if the liquid-impermeable cover layer 203 has a certain breathability, i.e. allows passage of water vapour through the layer 3. In addition, it is not necessary for the cover layers 202, 203 to consist of single material layers, and instead laminates of two or more layers of identical or different material can be used.

The two cover layers 202, 203 have a somewhat greater planar extent than the absorption body 204 and extend a short distance beyond the absorption body 204 around the whole of its periphery. The cover layers 202, 203 are connected to each other within the projecting portions 229, for example by means of adhesive bonding or welding with heat or ultrasound.

As in the previous illustrative embodiment, the absorption body 204 can be of any type suitable for the purpose.

Arranged on the outside of the liquid-impermeable cover layer 203 there is a securing member 235 in the form of an elongate area of self-adhesive material. Before use, the securing member 235 is preferably covered by a removable protective layer (not shown in the drawing) of paper, plastic film or the like, treated with a release agent. Instead of the adhesive configuration shown here, in the form of an elongate area of adhesive, a number of other configurations of the adhesive can be used, such as transverse bands, spots, full-surface coating, etc. Other types of securing members can alternatively be used, such as hook-and-loop surfaces, snap fasteners, girdles, special underpants, or the like. An incontinence protector 200 of the type shown is primarily intended for use by persons with relatively minor incontinence- problems and is therefore of such a size that it can easily be fitted in the crotch area of a pair of ordinary underpants. The securing member 235 in this case serves to hold the incontinence protector in place inside the underpants during use.

The incontinence protector 200 is essentially hourglass- shaped, with broader end portions 216, 217 and a narrower crotch portion 215, situated between the end portions 216, 217. The crotch portion 215 is that part of the incontinence protector which is intended, during use, to be arranged in the user's crotch region and to serve as the main receiving area for the bodily fluid which is excreted into the incontinence protector. The incontinence protector additionally has two transverse, rounded end edges 207, 208, and two longitudinal, curved side edges 205, 206 running between the end edges 207, 208.

Moreover, an elastic member 219, 220 is arranged along each side edge 205, 206 of the incontinence protector. The elastic members 219, 220 are of the same type as in the previously described illustrative embodiment and are secured, for example, by means of being adhesively bonded or welded to one or both cover layers 202, 203 in the projecting portions 229 of the cover layers 202, 203. The elastic members 219, 220 are secured to the cover material in the extended state. In the example shown, the elastic members 219, 220 are arranged between the two cover layers 202, 203. However, it is possible instead to arrange the elastic members on the outside of one or both cover layers . In addition, the elastic members 219, 220 can alternatively consist of elastic bands which are folded around the side edges 205, 206 of the incontinence protector. The purpose of the elastic members 219, 220 is to pull the material in the projecting cover portions 229 together, so that raised -side barriers 231, 232 are formed on both sides of the absorption body 204.

In order to keep the side barriers 231, 232 raised during use, and in order to give the incontinence protector an anatomically adapted shape, curved in the longitudinal direction, a shaping element 222 is arranged between the absorption body 204 and the liquid-impermeable cover layer 203. The shaping element 222 is expediently anchored to the liquid-impermeable cover layer 203 and/or to the absorption body 204, for example by means of adhesive bonding or welding.

The shaping element 222 is ladder-shaped and has two sub- elements 223, 224 which run in the longitudinal direction of the incontinence protector, along the side edges 205, 206. The shaping element 222 additionally has four transverse sub-elements 241 - 244 which are intended to counter deformation of the incontinence protector in the transverse direction.

The shaping element 222 expediently consists of flexurally elastic plastic, metal, or the like. For example, the shaping element 222 can be cast, or stamped out from a plastic sheet, or a metal plate. The design of the shaping element 222 gives it a resilient resistance to compression in the transverse direction, but still permits a certain adaptation of the width of the incontinence protector to the space between the user's legs. Moreover, the rigidity of the shaping element 222 is adapted to the contracting forces of the elastic members 219, 220, so that crumpling of the incontinence protector and collapse of the raised side barriers 231, 232 is avoided. The contracting force of the elastic members 219, 220 curves the incontinence protector longitudinally, as can best be seen from Figure 4. By adapting the rigidity of the shaping element 222 to the tensile- force of the elastic members 219, 220, a curvature is obtained which approximates to the shape of the user's body in the crotch region.

The sanitary towel 500 shown in Figure 5 represents a further example of an article according to the invention. The sanitary towel 500 has the same basic design as the incontinence protector 200 shown in Figure 2 and thus has an absorption body 504 enclosed in a cover 502, 503. The two cover layers 502, 503 form a contiguous joining edge 529 around the absorption body 504. At the crotch portion 515 of the sanitary towel, the cover layers 502, 503 project outwards and thus form securing flaps 545, 546 on both sides of the absorption body 504.

The securing flaps 545, 546 are provided with a securing member 547, 548, for example an adhesive, or in the form of a hook-and-loop surface. When in use, the securing flaps 545, 546 are folded around the leg edges of the user's underpants and are secured to the material on the outside of the underpants with the aid of the securing members 547, 548. Securing flaps 545, 546 of this type fulfil several functions. On the one hand, they ensure that the sanitary towel sits firmly anchored in the underpants, and, on the other hand, they hold the sanitary towel stretched between the leg edges of the underpants and thereby counteract deformation. The securing flaps 545, 546 also cover the leg edges of the underpants and thus in themselves constitute an edge leakage protection.

In addition to the securing flaps 545, 546, the sanitary towel can of course, like the incontinence protector shown in Figures 2 - 4, be provided with a securing member arranged on the liquid-impermeable cover layer 503. Longitudinal elastic edge barriers 531, 532 are arranged along the side edges 505, 506 of the sanitary towel, a short distance inside the edges of the absorption body 504. The edge barriers 531, 532 are formed by a separate barrier layer 509 arranged across each securing flap 545, 546 and across a portion of the sanitary towel nearest and inside each side edge 505, 506, outside the liquid-permeable cover layer 502. The barrier layer 509 is thus intended to be facing the user during use. Elastic members 519, 520 are secured to the liquid-permeable cover layer 502 to form the raised edge barriers 531, 532.

In order to counteract undesired deformation caused by the tensioning of the elastic members and the force which occurs during use, a shaping element 522 is arranged between the liquid-impermeable cover layer 503 and the absorption body 504, in a manner corresponding to the incontinence protector 200 which was described in connection with Figures 2 - 4. The shaping element is curved longitudinally by the elastic members 519, 520 and thus gives the sanitary towel an anatomically adapted shape, at the same time as the elastic barriers 531, 532 are kept raised and in contact with the user's body during use.

The shaping element 522 is slightly hourglass-shaped and is therefore narrowest at the crotch portion 515 of the sanitary towel. In this case, the shaping element 522 expediently has a width which, at the crotch section 515, is between 1 and 4 cm and preferably about 3 cm. Measurements have in fact shown that there is a critical area of limited space in the groin region between two muscle groups which run from inside the pelvic floor and down along each thigh. The distance between the two muscle groups has been found, in the genital region, to be surprisingly similar in all individuals, regardless of body shape and girth. Thus, the distance between a user's thighs is obviously influenced by fatness, while the distance between the" muscle groups in the user's crotch area is essentially the same, regardless of whether the user is thin, of normal weight or overweight.

It was found from these measurements that the factor which determines whether a user experiences discomfort in the form of pressure, or chafing against the inner sides of the thighs, is whether the absorbent article has a width which, in the critical area, markedly exceeds the distance between the muscle groups in the groin region. This distance has been found to be between about 30 mm and 35 mm. It has also been shown that an article with a width which, during use, exceeds 40 mm in the critical area is found by most users to be uncomfortable to wear. By contrast, discomfort is seldom experienced from an absorbent article pressing against or pushing aside fatty tissue which may be present in the genital region.

In the case of a soft, formable absorbent article, the limited space at the user's crotch means that the article is compressed in an uncontrolled manner between the user's legs and folded in order to fit between the thighs. However, if one component in the absorbent article has such rigidity that it cannot easily be compressed by the forces which normally occur during use, compression can of course only take place to a limited extent. It is therefore important, for reasons of comfort, that the width of the absorbent article in the crotch portion does not exceed the critical value which can be tolerated by the user.

The fact is of course that it is the width the article has during use which is relevant in assessing whether or not there is a risk of chafing. Soft components which deform during use thus do not contribute to the width of the article during use as much as do comparatively unyielding components .

The material which is used for the shaping element 522 is advantageously so rigid that it is not deformed transversely by the compressing forces which occur between the user's thighs. It is therefore important that the width of the shaping element 522, at least within that part which, during use, is intended to be arranged in the critical area between the user's legs, does not exceed 40 mm and preferably does not exceed 35 mm.

Figures 6 - 9 show a number of different possible designs of shaping elements according to the invention. A shaping element, for example of one of the types shown in Figures 6 - 9, can be firmly anchored in an absorbent article, for example by being connected to a component in the article, or by being arranged within the absorption body of the article. Alternatively, the shaping element can be connected to the article in a removable manner, as has been described in the context of the diaper shown in Figure 1. In the case of absorbent articles which do not have suitable pockets for holding a shaping element, other types of securing arrangements can of course be used. For example, hook-and-loop surfaces on the shaping element can cooperate with hook-and-loop surfaces on the absorbent article. Other types of cooperating securing members can also be used, such as snap fasteners, buttons, eyelets, hooks, or the like.

The invention must not be regarded as being limited to the embodiments described herein, and instead a number of further variants and modifications are possible within the scope of the attached patent claims. For example, it is possible to combine materials and components in several different ways without deviating from the invention as set out in the patent claims. The invention also covers all conceivable combinations of the illustrative embodiments described.

Claims

PATENT CLAIMS

1. An absorbent article, such as a diaper, an incontinence^* protector or a sanitary towel, with a generally elongate shape and with a longitudinal direction and a transverse direction, and comprising an absorption body (4) enclosed between a liquid-permeable cover layer (2) and a liquid-impermeable cover layer (3), and having two longitudinal side edges (5, 6), two transverse end edges (7, 8), and at least one elongate elastic barrier (31, 32), the elastic barrier (31, 32) comprising a piece of material (9) which can be raised in a direction away from the liquid-permeable cover layer (3), and an elastic member (19, 20) which is arranged with pretension in the longitudinal direction of the barrier (31, 32), c h a r a c t e r i z e d i n that a flexurally rigid shaping element (22) is arranged between two edges (7, 8) of the article, alongside the elastic barrier (31, 32) and with a main direction of extension coinciding with the direction of extension of the elastic barrier (31, 32), the shaping element (22) having an arched portion between the edges (7, 8), which portion is curved in a direction away from the liquid-permeable cover layer ( 2 ) and counteracts the contracting force occurring in the raisable piece of material (9) as a result of the pretension in the elastic member (19, 20), whereby the article has a barrier (31, 32) raised from the liquid-permeable cover layer (2).

2. An absorbent article according to Claim 1, c h a r a c t e r i z e d i n that the shaping element (22) comprises a flexurally elastic material, such as plastic or metal.

3. An absorbent article according to Claim 1 or 2, c h a r a c t e r i z e d i n that the shaping element (22) comprises an absorbent material.

4. An absorbent article according to Claim 3, c h a r a c t e r i z e d i n that the absorbent material is a flexura-lly elastic, flexurally rigid foam material.

5. An absorbent article according to any of Claims 1 to 4, c h a r a c t e r i z e d i n that the shaping element (22) runs in the longitudinal direction of the article, between the two end edges (7, 8) of the article.

6. An absorbent article according to Claim 5, c h a r a c t e r i z e d i n that the article has raised elastic edge barriers along both side edges (5, 6).

7. An absorbent article according to any of the preceding claims, c h a r a c t e r i z e d i n that the shaping element (222) has sub-elements (241-244) running in the transverse direction of the article.

8. An absorbent article according to Claim 7, c h a r a c t e r i z e d i n that the article has raised elastic edge barriers along at least one end edge.

9. An absorbent article according to Claim 6, c h a r a c t e r i z e d i n that the pretensioned elastic members (19, 20) are arranged along both side edges (5, 6) of the article, and in that the shaping element (22) exhibits a longitudinally curved shape as a result of the tensile stress in the elastic members (19, 20).

10. An absorbent article according to any one of the preceding claims, c h a r a c t e r i z e d i n that the two cover layers (202, 203) enclosing the absorption body (204) form a projecting edge portion (229) around the absorption body (204), and in that the elastic members (219, 220) are arranged in the projecting edge portion (229) along the side edges (205, 206) of the article, as a result of which the article has raised edge barriers (231, 232) along the side edges (205, 206), which edge barriers (231, 232) are formed by the projecting edge portion (229).

11. An absorbent article according to any one of the preceding claims, c h a r a c t e r i z e d i n that a barrier layer (9) is arranged across that surface of the liquid-permeable cover layer (2) which is directed away from the absorption body ( 4 ) , the barrier layer ( 9 ) having an opening (10) for passage of bodily excretions in towards the liquid-permeable cover layer (2), and in that the barrier layer (9) has elastic members (19, 20) which run in the longitudinal direction and are arranged on both sides of the opening (10), as a result of which the barrier layer (9) forms raised elastic edge barriers (31, 32) on both sides of the opening (10).

12. An absorbent article according to any of the preceding claims, c h a r a c t e r i z e d i n that the article has a securing member (235; 545, 546) for securing the article on underpants or a tie-on.

13. An absorbent article according to Claim 12, c h a r a c t e r i z e d i n that the securing member comprises securing flaps (545, 546) arranged along each side edge (505, 506) and intended to be folded around the leg edges of a pair of underpants during use of the article.

14. An absorbent article according to any of the preceding claims, c h a r a c t e r i z e d i n that the shaping element (22) consists of two flexurally rigid elongate sub-elements (23, 24) running in the longitudinal direction.

15. An absorbent article according to Claim 14, c h a r a c t e r i z e d i n that the elongate sub- elements (23, 24) are crossed.

16. An absorbent article according to any one of the preceding claims, c h a r a c t e r i z e d i n that the shaping element (22) is arranged in the article in a removable manner.

17. An absorbent article according to Claim 16, c h a r a c t e r i z e d i n that the article has pockets (18) in which end portions (25-28) of the shaping element (22) are held in a removable manner.

18. An absorbent article according to any of the preceding claims, c h a r a c t e r i z e d i n that the shaping element (22) is firmly secured to one of the components included in the article.