# Patent

## Title
Absorbing disposable incontinence diaper

## Abstract

A diaper having a main part comprising a front area, a rear area and a crotch area therebetween, wherein the main part comprises an absorbent core, and with rear side sections joined on both sides to the rear area and front side sections joined on both sides to the front area which extend in the transverse direction past lateral front and rear longitudinal edges of the main part, connect the front area and the rear area, wherein, at least on the side facing the crotch area, the front and rear side sections; are designed in such a fashion that they extend at an inclination with respect to the longitudinal direction or are curved for forming leg opening areas, and the front and rear side sections of the front area and rear area differ from each other with respect to at least one primary property.

## Background
This application is a continuation of PCT/EP2008/005571 filed on Jul. 9, 2008 and also claims Paris Convention priority of EP 07 015 141.0 filed on Aug. 2, 2007 the entire disclosures of which are hereby incorporated by reference


BACKGROUND OF THE INVENTION
The present invention concerns a disposable absorbent incontinence diaper with a main part comprising a front area with front lateral longitudinal edges, a rear area with rear lateral longitudinal edges and a crotch area which is disposed therebetween in the longitudinal direction and comes to rest between the legs of a user, wherein the main part comprises an absorbent core, and with rear side sections which are joined on both sides to the rear area, and front side sections which are joined on both sides to the front area. The disposable incontinence diaper is designed for one-time use for adults.
Disposable incontinence diapers of this type are disclosed e.g. in DE102005048868A1. DE102005048868A1 also discloses different designs of the side sections, i.e. the rear side sections are more elastic than the front side sections.
The above-mentioned side sections of disposable incontinence diapers of this type are often formed from a different material than the main part. The side sections, which are often also called “ears” of the disposable incontinence diaper, may be breathable, in particular, permeable to air and water vapor, whereas the main part, which is often also called the chassis, may be impermeable to liquid. For closing the disposable incontinence diaper, the side sections, which are preferably permanently joined to the rear area, are moved to the belly side of the user and detachably connected at that location, either to the outer side of the front area of the main part or to the outer side of the side sections of the front area.
As disclosed in DE102005048868 A1, both the main part as well as the side sections of disposable incontinence diapers of this type have a rectangular shape. DE102004021353A1 also discloses a disposable incontinence diaper of this type. DE102004021353A1 moreover teaches to previously fold the side sections and to hold the prefold through detachable fixation prior to use. The side sections are preferably prefolded in a fast running diaper machine prior to fixation of the side sections to the diaper main part, i.e. the side sections are preferably prefolded and prefixed in this configuration prior to being joined to the diaper main part. Although this incontinence diaper can also be produced at high speed and thereby in a very economical fashion, and the prefolded side sections can preferably be opened by pulling once, the wear comfort of the conventional disposable incontinence diaper is, however, not satisfactory.
SUMMARY OF THE INVENTION
In order to solve this problem, the invention proposes to design the side sections, at least on the side facing the crotch area, in such a fashion that they extend at an inclination to the longitudinal direction or are curved for forming leg opening areas, and to provide the main part, at least in the crotch area, with an hourglass shape, wherein the inclined or curved extension of the side sections and the hourglass-shaped contour of the main part on both longitudinal sides of the disposable incontinence diaper is formed by one single respective separating process, which includes the side sections and the main part. The separating process, which includes the side sections and the main part, is thereby performed at a time at which the front and rear side sections have already been joined to the main part. This ensures that the leg-opening contour of the side sections extends quasi continuously in the crotch area of the main part to form the hourglass contour of the main part at that location. In accordance with the invention, the side sections of the front area and rear area differ with respect to at least one primary property selected from the following group: type of material, basis weight, breathing activity, density, stretchability, closing force, surface extension, thickness, color. This ensures optimization of the side sections with respect to their different functions, which finally further increases the wear comfort of the disposable incontinence diaper.
In accordance with the invention, the separating process also includes the area of the front and rear side edges of the main part, wherein the front side edge of the main part means the section of the side edge of the main part to which the front side sections are joined, and the rear side edge of the main part is that part of the side edge of the main part, to which the rear side sections are joined. In this fashion, the separating process is continuously guided through side section material or main part material to be separated. The leg opening areas are thereby exclusively formed by the edges resulting from one single respective separating process, in particular of one single cut. The diaper can moreover be economically produced, since, despite the optimized leg opening, only little cutting waste is produced.
In accordance with a preferred embodiment, the separating process is a cutting or a punching process. The separating process may, in particular, be effected through knife drums, which are known per se.
The contours of the leg opening areas may have straight sections that extend, in particular, at an inclination with respect to the longitudinal direction of the disposable incontinence diaper and/or curved sections. In a preferred embodiment, the contour of the leg opening areas has only curved sections. The minimum curve radius of the leg opening areas is preferably at least 5 mm, in particular, preferably at least 10 mm. The contour of the leg opening areas preferably comprises curved sections with different curve radii.
It has also turned out to be advantageous to form the front and/or rear side sections from a non-woven material. In particular, all non-woven materials can be used, which contain at least one composition component on the basis of a thermoplastic polymer. The non-woven materials may contain fibers of PE, PP, PET, Rayon, cellulose, PA and mixtures of these fibers. Bi-component or multi-component fibers are also feasible and advantageous. In particular, card webs, spunbonded non-woven materials, water jet-needled non-woven materials, SM non-woven materials, SMS non-woven materials, SMMS non-woven materials and also laminates of one or more of these non-woven material types are advantageous, wherein S stands for spunbonded and M for meltblown non-woven material layers. Spunbonded non-woven materials are particularly preferred, since they have high rigidity in the longitudinal and transverse direction and are thereby particularly resistant to shearing forces exerted on them, which result from engagement of mechanical closing aids, if present. In order to prevent fibers from being torn out of the non-woven composite when the mechanical closure aids are detached, the non-woven component is advantageously provided with an embossed pattern, which preferably binds all fibers of the non-woven component. A thermo-embossing pattern is thereby particularly advantageous, which, in particular, is preferably generated through calendering the non-woven material while adding thermal energy.
First elastic elements with a component in the longitudinal direction are moreover advantageously joined to the main body on the side next to the longitudinal edges of the absorbent core. These elastic elements may extend exactly in the longitudinal direction, i.e. in a straight line, or with particular advantage, also follow a given contour along the leg opening. The elastic elements are then curved along the leg opening. In a particular further development of this inventive idea, the elastic elements do not extend into the side sections but are limited to a position within the main part. Second elastic elements, which have, in particular, the shape of so-called upright cuff elements (disclosed e.g. in EP0263720A1) and extend in the first longitudinal direction, may be joined to the diaper main part web. These preferably upright second elastic elements quasi flank a center of the diaper main part or absorbent core. They may be provided in the area of the absorbent core edges, within the absorbent core edges or outside of the absorbent core edges. They form a lateral leakage protection of the disposable incontinence diaper.
In another advantageous further development of the invention, the side sections have an inner side and an outer side, wherein the rear side sections have closing means with, in particular, mechanical closing aids, and wherein the closing means can be detachably fixed at least in some areas both to the outer side of the rear side sections and also to the outer side of the front side sections for proper fixation of the disposable incontinence diaper to the body of a person.
In a further development of this inventive idea, the closing means can be detachably fixed to at least some areas of the outer side of the main part and also of the outer side of the front side sections for proper fixation of the disposable incontinence diaper to the body of a person, wherein the holding forces between the closing means and the outer side of the front side sections are preferably larger than the holding forces between the closing means and the outer side of the main part. For this reason, the user normally fixes the closing means to the front side sections. The holding forces for retention over the belly, determined between the closing means that comprise, in particular, mechanical closing aids and the outer side of the main part are preferably 20-57 N/25 mm, in particular, 25-50 N/25 mm.
The outer side of the main part of the disposable incontinence diaper is preferably formed, at least in some areas, in particular, over the entire surface by a non-woven material. This provides the disposable incontinence diaper with a “textile-like” appearance. In this case, the back sheet of the main part is advantageously formed from a non-woven film material laminate, wherein the non-woven layer is disposed on the outside and the film material layer on the inside facing the absorbent core, such that the non-woven layer forms the outer side of the main part. This ensures that the main part is impermeable to liquid, and also that the diaper is skin-friendly. The film material layer of this non-woven film material laminate is then preferably formed from a one-layered or multi-layered liquid-impermeable film material, which is however preferably breathable, wherein the breathability of the front and/or rear side sections is preferably larger than the breathability of the non-woven film material laminate that forms the back sheet of the disposable incontinence diaper.
In accordance with another particularly preferred embodiment, the rear and/or front, preferably only the rear side sections, have a reinforcing means which, as viewed in the transverse direction, is narrower than a respective side section and is provided at least in an area that bridges the side edge of the main part, i.e. extends over a lateral side edge section of the main part and also over part of the side section in the transverse direction. With respect to design and arrangement of the reinforcing means, reference is made to PCT/EP2007/003733, the full content of which is hereby incorporated by reference.
In accordance with the invention, the rear side sections differ from the front side sections with respect to at least one, in particular at least two, moreover, in particular, at least three and, in particular, at least four primary properties, selected from the following group: type of material, basis weight, breathability, density, stretchability, closing force, surface extension, thickness, color.
Type of material: In particular, when both side section components are formed from a non-woven material, the front side sections are e.g. preferably made from a softer, skin-friendlier non-woven material than the rear side sections, since the front side sections are disposed on the inside when the diaper is properly applied to the body. It may also be advantageous to form the rear side sections from a material having a higher resistance to tensile forces, since the closing means are preferably disposed on the rear side sections and strong tensile forces act on the side sections via the closing means when the diaper is applied. Preferred differentiations with respect to type of material can be realized through the fiber type that is used, the production method of the non-woven material or laminate formation.
Basis weight: the above-mentioned requirements can preferably be obtained at least partially through differentiation of the basis weight, measured in g/m2. The basis weight of the front side sections preferably differs from that of the rear side sections by at least 10%, in particular by at least 20%, and moreover, in particular, by at least 30%. The basis weight of the front and/or rear side sections is preferably 15-60 g/m2, in particular 20-45 g/m2, moreover, in particular 25-40 g/m2 and moreover, in particular 28-35 g/m2.
Breathability: The front and/or rear side sections ((20, 22) are preferably formed by a non-woven material that is permeable to air and/or water vapor. Since the subjective perception of impairment of the wear comfort differs among the target groups (e.g. bedridden patients versus mobile patients), it may be advantageous to improve the breathability of the front or rear side sections. The front side sections preferably differ from the rear side sections with respect to breathability measured as water vapor permeability (WVTR) according to DIN 53 122-1 (Issue: 2001-08) by at least 5%, in particular, by at least 10% and moreover, in particular, by at least 20%. The breathability of the front and/or rear side sections is thereby preferably at least 1000 g/m2/24 h, in particular at least 1500 g/m2/24 h, moreover preferably at least 2000 g/m2/24 h.
Density and thickness: The subjective perception of softness of the side section material and thereby a substantial component of the wear comfort may preferably also be controlled by differentiation of density and/or thickness of the material. The thickness measured in mm, determined with a test pressure of 0.5 kPa and/or the density measured in g/cm2, determined from the values: basis weight and thickness of the material of the front sections differs from the density and/or thickness of the rear side sections by at least 15%, in particular by at least 20% and moreover in particular by at least 25%.
Stretchability: Stretchability in the present case defines the ratio between an increase in length of a side section of the disposable incontinence diaper due to the action of a force, and the original length. During use of such disposable incontinence diapers, forces act on the side sections, in particular, in the peripheral direction, i.e. the transverse direction of the diaper. “Stretchability” thereby means the degree of extension of the side section under the action of a force in the transverse direction of the diaper. This means, the higher the degree of extension, the higher the stretchability. A rear side section is preferably more elastic than a front side section under the action of forces exerted during normal use of the diaper. In particular, according to the test method described in DE102005048868 A1, a rear side section is more elastic than a front side section under the action of a force of 45N. A rear section preferably shows an extension of at least 20%, in particular at least 25% and in particular at least 30% under the action of a force of 45N. A front side section, however, shows only an extension of preferably at most 15%, in particular at most 10% and moreover in particular at most 8% under the action of a force of 45N. At least one rear side section is preferably elastically stretchable at least in the transverse direction. The stretchability of the side section is called elastic when, under the temporary action of a force, an extension of at least 40% is obtained and, when this force is cancelled, an extension (remaining extension) of at most 20% remains. In an advantageous further development of the invention, the elastic stretchability of a rear side section in the transverse direction is at least 40%, in particular at least 50%. According to a further inventive idea, the absolute degree of elastic extension of a rear side section is at least 3 cm, in particular, at least 5 cm, and moreover, in particular, at least 7 cm.
Closing force: The closing force of the side sections defines the holding force between the closing means of the rear side sections and the outer side of the side sections. The holding forces between the closing means and the outer side of the rear side sections are thereby preferably smaller than the holding forces between the closing means and the outer side of the front side sections. This advantageously permits the user to preferably fix the closing means to the front side sections, which considerably improves the fit and wear comfort of the diaper. The holding forces mentioned above and below are preferably determined as holding forces for retention over the belly. The holding forces for retention over the belly are to be determined according to the test method described in EP06022450.8. The holding forces for retention over the belly determined between the closing means which comprise, in particular, mechanical closing aids, and the outer side of the front side sections are preferably 58-90 N/25 mm, in particular, 60-80 N/25 mm. The holding forces for retention over the belly between the closing means comprising, in particular, mechanical closing aids, and the outer side of the rear side sections are preferably smaller than the holding forces for retention over the belly between the closing means and the outer side of the front side sections. They are preferably also at least 15 N/25 mm, in particular, at least 30 N/25 mm.
The mechanical closing aids preferably comprise conventional Velcro hook elements. In another embodiment, at least one closing means, preferably all closing means also comprise an adhesive closing aid, in particular, an adhesive zone, e.g. as disclosed in EP06022450.8.
Surface extension: In a further advantageous development of the invention, the rear side sections have a larger surface extension than the front side sections, which is preferably larger by at least 10%, in particular by at least 15%. The length of the rear side sections, i.e. their extension in the longitudinal direction of the diaper may be at least 10 cm, in particular, at least 15 cm, in particular at least 18 cm and moreover, in particular, at least 22 cm. It is also advantageous for the length of the rear side sections to be at least 10%, in particular, at least 15%, moreover, in particular, at least 20% and moreover, in particular, at least 22% of the overall length of the disposable incontinence diaper. The overall length of the disposable incontinence diaper is preferably 50 to 120 cm, in particular 60 to 110 cm, and moreover, in particular 70 to 110 cm. The front side sections also advantageously have a shorter extension in the longitudinal direction than the rear side sections, in particular, by at least 5%, in particular by at least 10% and moreover, in particular, by at least 15% and, in particular, at most 50%. In a further advantageous development of the invention, the width of the side sections, i.e. the extension of the side sections past the side edge of the diaper main part is 10 to 40 cm, in particular 12 to 30 cm, in particular 13 to 25 cm. The front side sections preferably have the same width as the rear side sections.
Color: It may also be advantageous to differentiate between the front and the rear side section with respect to color in order to show the user the function of the front side sections as the preferred area of application of the closing means.
The invention also claims a method for producing an inventive disposable incontinence diaper. A main part web is thereby initially supplied in the longitudinal direction, wherein the main part web may preferably comprise a non-woven material and/or an absorbent core material and/or a back sheet material. The back sheet material may, in particular, be a film material or a liquid-impermeable non-woven material or a non-woven film material laminate. Moreover, a first side section web, which forms rear side sections, is supplied in the longitudinal direction, and a second side section web forming front side sections is supplied in the longitudinal direction. The materials of the first and second side section webs differ from each other with respect to at least one primary property. Closing means are preferably joined to the first side section web. Two first and/or two second side section webs are preferably supplied in the longitudinal direction, which are advantageously formed in an upstream method step in which a first material web and/or a second material web are divided in the longitudinal direction. First and second sections are separated from a first and a second side section web in a direction transverse to the longitudinal direction. The sections separated from a first side section web are then joined to a section of the main part web that forms the respective rear area, for forming the rear side sections, and the sections that are separated from the second side section web are joined to a section of the main part web that forms a respective front area, for forming the front side sections. The sections are preferably joined in a clocked manner to an endless non-woven material web of the main part web, wherein the non-woven material web forms a side of the disposable incontinence diaper to be produced that faces the body. The material openings are finally formed to obtain the inclined or curved shape of the side sections and the hourglass-shaped contour of the main part on both longitudinal sides of the disposable incontinence diaper for generating leg opening areas in one single respective separating process, performed, in particular, as a cutting or punching process. The separating process thereby preferably includes the main part even in the area of the front and rear side edge of the main part, i.e. that area where the side sections have been previously joined to the main part. The separating process is preferably guided along a line that has straight and/or curved sections, in particular, exclusively curved sections. This line is preferably guided in such a fashion that, starting from a point A on the side edge of the front side sections, it initially extends in a curved fashion to the inside towards the crotch area to a point B of the front side edge of the main part, then into the main part, and then further through the crotch area of the main part, and subsequently in a curved fashion to the outside through a point C of the rear side edge of the main part and finally to a point D on the side edge of the rear side sections. The line is thereby preferably guided on its path from point A to point D in a continuous fashion through side section or main part material that is to be separated. The line is thereby preferably not guided through the absorbent core, such that the absorbent core edges remain at a distance from the leg-opening contour. One single tangent can thereby preferably be disposed at any point of the line between the points A and D, i.e. the slope of the curve or straight sections can be uniquely determined, wherein the points A and D are excluded from this condition. A knife drum preferably realizes this separating process.
In accordance with a preferred embodiment of the method, the main part web is separated through the sections in a direction transverse to the longitudinal axis for forming separate disposable incontinence diapers.
It has turned out to be advantageous to produce the disposable incontinence diapers in such a fashion that the rear area of one disposable incontinence diaper follows the rear area of the other disposable incontinence diaper and the front area of one disposable incontinence diaper follows the front area of another disposable incontinence diaper, when the disposable incontinence diapers are supplied successively in the longitudinal direction. In this case, one section that is separated from the side section webs in a direction transverse to the longitudinal direction preferably forms the side sections of two successively supplied disposable incontinence diapers.
Further features, details and advantages of the invention can be extracted from the enclosed claims and the drawing and following description of preferred embodiments of the invention.



BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a top view of an inventive disposable incontinence diaper;
FIG. 2 shows a further top view of the inventive disposable incontinence diaper according to FIG. 1;
FIGS. 3a, 3b shows a schematic view of an inventive production method;
FIG. 4 shows a schematic view of the steps of an inventive production method.



DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 schematically shows a top view of the inner side, i.e. the side of a disposable absorbent incontinence diaper 2 facing the body in the unfolded flat state. The disposable incontinence diaper 2 comprises a main part 4 with a front area 6, a rear area 8 and a crotch area 10 disposed therebetween in the longitudinal direction. An absorbent core 12 is furthermore indicated, which is usually disposed between the chassis-forming materials of the main part 4, i.e., in particular, between a liquid-permeable top sheet 11 formed from a non-woven material, and a substantially liquid-impermeable back sheet 13 of the main part 4, which is formed from a film material. The back sheet 13 may also be formed from a liquid-impermeable non-woven material or a non-woven film material laminate, wherein the non-woven layer is disposed to rest on the outside and the film material layer on the inside facing the absorbent core. This provides the disposable incontinence diaper 2 with a “textile-like” appearance. First elastic elements 60 are joined to the main part 4, between top sheet 11 and back sheet 13, on the side next to the longitudinal edges of the absorbent core 12. The elastic elements 60 substantially extend in the longitudinal direction, i.e. have a considerable component in the longitudinal direction, wherein they extend in a curved fashion along the leg opening area section to be associated with the crotch area 10. The disposable incontinence diaper 2 also comprises front side sections 22 and rear side sections 20, which are joined as separate non-woven material components to both sides of the main part 4. The side sections 20, 22 are permanently connected to chassis-forming materials of the main part 4, i.e. for example to the back sheet 13 and/or the top sheet 11 in an overlapping area 18 which is shown with hatched lines. These overlapping areas at which the side sections are permanently connected to the main part are hereby defined as “seams”. The side sections 20, 22 extend in the transverse direction 30 past the front and rear longitudinal edges 42, 41 of the main part. Front and rear longitudinal edges 42, 41 of the main part in accordance with the present invention define those longitudinal edge areas of the main part to which the side sections are joined and past which they extend. The longitudinal extension of the front and rear side edges of the main part 42, 41 thereby also define the longitudinal extension of the front area 6 and of the rear area 8 of the disposable incontinence diaper 2 (illustrated in FIG. 1). The side sections 20, 22 are designed and determined to be connected to each other when the disposable incontinence diaper 2 has been applied in order to form a hip area of the hygiene article, which is continuous in the peripheral direction. Towards this end, the side sections 20, 22 provided on each side of the main part 4, are connected to each other. Mechanical closing means 32, in particular, comprising mechanical closing aids such as Velcro hooks, are thereby provided on the rear side sections 20, which can be detachably fixed to the outer side of the front and rear side sections 20, 22. The closing means can preferably also be detachably fixed to the outer side of the main part. The front side sections 22 and also the rear side sections 20 are formed from a non-woven material, in the present case a PP spunbonded non-woven material. The basis weight of the non-woven material of the front side sections is 30 g/m2. The thickness of the fibers that form the non-woven material is 2dtex. The outer and inner sides of the spunbonded non-woven material have an embossed pattern 14, which is only schematically indicated in FIG. 1. The joining areas generated by hot embossing calendering are formed by a plurality of lines, i.e. by two groups of lines that extend parallel within each group, wherein the lines of one group intersect with those of the other group at an angle of 33 degrees in order to form a regular diamond pattern, such that interconnected diamond-shaped loop areas 15, which are disposed like islands, are surrounded by linear joining areas 16. The lines that form the joining areas 16 have a width of 1.0 mm and an embossing depth of 0.6 mm in the case shown. The separation between two neighboring lines, extending in parallel, of both groups of lines is 4.7 mm. The joining surface, i.e. the sum of the surface of all joining areas 16 with respect to the overall surface of the joining pattern (joining areas plus loop areas) is 32%. The closing means 32 of the rear side sections 20 can be brought into safe engagement with these loop areas 15. The holding forces for retention over the belly between the closing means 32 and the outer side of the front side sections 22 are preferably at least 58 N/25 mm.
The basis weight of the non-woven material of the rear side sections 20 is 25 g/m2 in the example shown. An embossed pattern that forms loop areas and joining areas is not provided. The holding forces for retention over the belly between the closing means 32 and the outer side of the rear side sections 20 are therefore smaller than the holding forces for retention over the belly between the closing means 32 and the outer side of the front side sections 22. They are preferably nevertheless at least 15 N/25 mm. As is illustrated in FIG. 1, the rear side sections 20 also have a larger surface extension than the front side sections 22.
The front and rear side sections therefore differ from each other with respect to at least three of their primary properties, i.e. basis weight, closing force and surface extension.
Due to the difference in closing force between the front and rear side sections, the user will prefer to fix the closing means 32 to the front side sections 22, which is favorable for the fit of the diaper.
As is also illustrated in FIG. 1, the leg opening areas 50 are formed by front and rear side sections 20, 22 that are curved towards the crotch area, and by the hourglass-shaped contour of the main part 4. Hourglass-shaped contour of the main part means in this case any narrowing shape of the main part 4 in the crotch area 10, i.e. any shape, including shapes that are not curved or not exclusively curved, wherein the crotch area 10 of the main part 4 has a shorter extension in the transverse direction 30 than the front area 6 and/or the rear area 8 of the main part.
The continuity of the leg opening 50 is formed by one single cut on each side, which includes the side sections 20, 22 as well as the main part 4, and is thereby continuously guided through side edge or main part material to be separated. This is even more clearly shown on the left hand side of FIG. 2 that shows the right-hand leg opening area in the applied state. The material openings 62 shown in hatched lines are formed from previously rectangular side sections and the main part 4 that is initially provided with straight side edges that extend parallel to each other in the longitudinal direction 28, through one single curved cut along a line 7 for obtaining the curved shape of the side sections 20, 22 and the hourglass-shaped contour of the main part 4. It is shown in detail that the intersecting line 7 extends starting from a point A on the side edge of the front side sections 22 in a curved shape to the inside towards the crotch area 10 at first to a point B of the front side edge 42 of the main part 4, then into the main part 4, then further through the crotch area 10 of the main part 4, and then subsequently in a curved shape to the outside through a point C of the rear side edge 41 of the main part 4, and finally to a point D on the side edge of the rear side sections 20. One can see that the intersecting line 7 is not guided through the absorbent core 12, such that the absorbent core edges remain at a distance from the leg-opening contour. In the case shown, the contour of the leg opening area has exclusively curved sections, wherein the curve radius is obviously not constant, i.e. the leg opening contour as a whole does not have a circular shape but comprises sections with different curve radii. The curve radius on the outside in a section AB that extends to the side edge of the side sections is thereby considerably larger than in a section CD that includes point C. The curve radius at any point of the leg opening contour is preferably at least 5 mm, preferably at least 10 mm. Apart from points A and D (these are both end points of the intersecting line 7 and therefore of the leg opening contour, and therefore also end points of the side edges of the side sections 20, 22) one single tangent can be applied at any point of the intersecting line 7.
For reasons of clarity, FIG. 2 shows the left-hand leg opening area (at the right-hand side of the figure) as in FIG. 1, i.e. without illustrating the position of the cut.
FIGS. 3a, 3b schematically show an inventive method for producing the disposable incontinence diaper shown in FIGS. 1 and 2. FIG. 3a thereby shows the supply and transport of a first endless material web 50a in the longitudinal direction L, wherein the material web 50a has side edges 52a which extend parallel to each other in a straight line. Closing means 32 have previously been joined to both sides of the yet endless material web 50a. The positions of the imaginary lines of the later separating cuts for forming individual rear side sections 20 of the disposable incontinence diaper to be produced are designated with reference numeral 8a. The first material web 50a is initially divided in the longitudinal direction L into two first side section webs 51a. Rectangular first sections 66a are subsequently separated from both side section webs 51a in a direction transverse to the longitudinal direction L, wherein later in the production process of the disposable incontinence diaper, sections of each side section web 51a are separated for joining either only the left-hand or only the right-hand side edge of an endless main part web 70.
FIG. 3a moreover shows the supply and transport of a second endless material web 50b in the longitudinal direction L, wherein the material web 50b has side edges 52b, which extend in a straight line parallel to each other. The position of the imaginary lines of the later singling cuts for forming individual front side sections 22 of the disposable incontinence diaper to be produced have reference numeral 8b. The second material web 50b is initially also divided in the longitudinal direction L into two second side section webs 51b. Rectangular second sections 66b are subsequently separated in a direction transverse to the longitudinal direction L from both side section webs 51b, which are joined to the left or respectively right-hand side edge of an endless main part web later in the production process of the disposable incontinence diaper as is described in more detail below. In the case shown, the sections 66a have a larger extension in the longitudinal direction L than the sections 66b. 
The first and second rectangular sections 66a, 66b are then supplied to an endless main part web 70 which is conveyed in the longitudinal direction L, as is illustrated in FIG. 3b. In the case shown, the main part web 70 comprises a non-woven material and an absorbent core material, i.e. an endless non-woven material web 71 that forms the top sheet, i.e. a side of the disposable incontinence diaper to be produced that faces the body, with straight parallel extending side edges 72 and an endless number of successively disposed and spaced apart absorbent cores 12, which have been previously disposed thereon. The absorbent cores 12 contain a mixture of super-absorbent materials (SAP) and fluffed cellulose fibers. The sections 66a, 66b are alternately fixed with dual use to both sides of the non-woven material, i.e. the side edges 72 of the main part web 70. In this connection, only sections to be joined to the left-hand side edge of the main part web or sections to be joined to its right-hand side edge are separated from one of the respective side section webs 51a, 51b. Separating of the sections 66a, 66b from the side section webs 51a, 51b, supply to the main part web 70 and subsequent joining of the sections 66a, 66b to both side edges 72 of the main part web is preferably performed using devices called slip-cut or also cut-and-place-units which are known to the expert per se and are not shown in FIGS. 3a, 3b. 
The illustrated imaginary lines of the later singling cuts 80 show that each separated section 66a, 66b forms the side sections 20, 22 of two successively supplied disposable incontinence diapers 2. Towards this end, the disposable incontinence diapers 2 are produced in such a fashion that, when the disposable incontinence diapers are supplied successively in the longitudinal direction L, the rear area 8 of one disposable incontinence diaper joins the rear area 8 of the other disposable incontinence diaper and the front area 6 of one disposable incontinence diaper joins the front area 6 of the other disposable incontinence diaper.
Directly after joining the sections 66a, 66b, an endless back sheet web 73, in particular a film material web, which forms the back sheet 13 of the diaper to be produced, is supplied to the main part web 70. The back sheet web 73 has a width that corresponds to the non-woven material web and side edges, which also extend in a straight line parallel to each other. In an application and joining station (only schematically indicated by arrow 9), the back sheet web 73 is supplied from the top to the main part web 70 in a centered fashion such that the absorbent core comes to rest between the back sheet web and non-woven material web, and the back sheet web and non-woven material web are directly connected to each other outside of the contour of the absorbent core 12 through conventional joining methods, such as gluing, thermal welding or ultrasound welding.
A laminate, in particular, a non-woven film material laminate web could also be supplied to the main part web 70 as the back sheet web 73. In this case, the non-woven material layer of the laminate would preferably be disposed on the outside and the film material on the inside towards the absorbent core 12.
FIG. 3b shows that, in the further course of the process for producing the disposable incontinence diaper after joining the sections 66a, 66b and the back sheet web 73 to the main part web 70, the leg opening areas 50 are formed on both longitudinal sides of the main part web, which are provided with sections 66a, 66b, for obtaining a curved shape of the side sections 20, 22 and the hourglass-shaped contour of the main part 4. This is effected by a knife drum (not shown) on each side in the form of one single continuous cut which, as explained in more detail above with respect to FIG. 2, is guided continuously through side section material or main part material to be separated, such that a continuous leg opening area 50 is generated that is formed exclusively by the edges of this single cut.
In a further method step shown in FIG. 3b, the still endless web, which is provided with the leg openings 50, is further supplied towards a singling station 75 (not shown in detail) where a separating cut is performed substantially transversely to the supply direction L which corresponds to the longitudinal direction 28 of the disposable incontinence diaper 2 to be produced, e.g. also using a rotating knife drum or a punching tool. The position of the separating cut is indicated in the figures by reference numeral 80. It is performed in such a fashion that it extends in each case through the applied sections 66a, 66b, i.e. the web is separated in a transverse direction through the sections 66a, 66b. 
In the described case (shown in FIG. 3b), at the time at which the sections 66a, 66b are joined, the main part web 70 already comprises a composite of non-woven material 71 and absorbent cores 12 which are disposed thereon.
In accordance with a further inventive idea, it would also be feasible and particularly advantageous (as schematically shown in the side view of FIG. 4) to initially separate the double-purpose sections 66a, 66b from the side section webs 51a, 51b in a clocked fashion, in particular, using so-called slip-cut-units 94, and to join them to both side edges of a main part web 70a, which consists at that time exclusively of the non-woven material web 71 forming the top sheet of the disposable incontinence diaper to be produced. Only subsequent thereto the, in particular, still endless first composite 90 of non-woven material web 71 and sections 66a, 66b is connected to the further diaper components. In this case the, in particular, still endless first composite 90 of the non-woven material web 71 and the sections 66a, 66b is preferentially supplied to a second composite 91 of an, in particular, endless back sheet web 73 that forms the back sheet of the diapers to be produced, in particular, an endless film material or non-woven film material laminate web, and discrete successive, spaced apart absorbent cores 12 which are disposed on this web, and the first composite 90 is joined with the second composite 91. The first composite 90 and the second composite 91 could advantageously be joined by supplying the components to a pressing and joining gap 93 of a rotating roller pair 92a, 92b (illustrated in FIG. 4). The absorbent cores 12 are thereby disposed between the back sheet web 73 and the non-woven material web 71 and the non-woven material web 71 is connected directly to the back sheet web 73 outside of the contour of the absorbent core 12 and joined therewith. This is preferably followed by forming the leg opening areas and subsequent thereto singling the disposable incontinence diapers as is described with reference to FIG. 3b (not shown in FIG. 4).
In an alternative method process (not shown), the first composite could also be initially supplied to a web of successive, spaced apart, discrete absorbent cores, or these absorbent cores could be disposed on the first composite in a clocked fashion and fixed thereon, if necessary. Subsequent thereto or also almost at the same time, a back sheet web, in particular, an endless film material or non-woven film material laminate web forming the back sheet of the diapers to be produced, may be supplied to the main part web which comprises at that time the first composite of non-woven material web and sections 66a, 66b, and the absorbent cores, and be connected to the main part web. This is followed, in turn, by formation of the leg opening areas and subsequent thereto singling of the disposable incontinence diapers as described with respect to FIG. 3b. 
The present invention thereby provides, for the first time, a disposable incontinence diaper with front and rear side sections that are joined to the main part and differ from each other with respect to at least one of their primary properties, wherein the disposable incontinence diaper has continuous leg opening areas, i.e. leg opening areas which are exclusively formed by the edges formed by one single respective separating process, in particular, one single cut, such that the disposable incontinence diaper has a perfect fit and superior wear comfort and is furthermore economic and simple to produce with minimum cutting waste.

## Claims

1. A disposable absorbent incontinence diaper for wear by a user, the diaper comprising:
a main part having a front area with a first front lateral longitudinal edge and a second front lateral longitudinal edge, a rear area with first rear lateral longitudinal edge and a second rear lateral longitudinal edge and a crotch area disposed between said front area and said rear area in a longitudinal direction, said crotch area resting between legs of the user, said main part also having an absorbent core;
a first front side section having an inner side and an outer side;
a second front side section having an inner side and an outer side;
a first rear side section having an inner side and an outer side;
a second rear side section having an inner side and an outer side;
a first front seam disposed between and joining said first front side section to said front area proximate to said first front lateral longitudinal edge, said first front side section thereby protruding in a transverse direction past said first front lateral longitudinal edge;
a second front seam disposed between and joining said second front side section to said front area proximate to said second front lateral longitudinal edge, said second front side section thereby protruding in a transverse direction past said second front lateral longitudinal edge;
a first rear seam disposed between and joining said first rear side section to said rear area proximate to said first rear lateral longitudinal edge, said first rear side section thereby protruding in a transverse direction past said first rear lateral longitudinal edge;
a second rear seam disposed between and joining said second rear side section to said rear area proximate to said second rear lateral longitudinal edge, said second rear side section thereby protruding in a transverse direction past said second rear lateral longitudinal edge;
a first closing means attached to said first rear side section, said first closing means having first closing aids, wherein a releasable holding force generated between said first closing means and said outer side of said second rear side section is less than a closing force generated between said first closing means and said outer side of said first front side section when closing the diaper; and
a second closing means attached to said second rear side section, said second closing means having second closing aids, wherein a releasable holding force generated between said second closing means and said outer side of said first rear side section is less than a closing force generated between said second closing means and said outer side of said second front side section when closing the diaper, wherein said first front side section, said main part and said first rear side section share a common first continuous outer edge defining a first leg opening, said first continuous outer edge slanting inwardly through said first front side section towards said crotch area and intersecting said first front seam before travelling into said crotch area of said main part and subsequently curving outwardly to cut through said first rear seam and slant outwardly through said first rear side section, wherein said second front side section, said main part and said second rear side section share a common second continuous outer edge defining a second leg opening, said second continuous outer edge slanting inwardly through said second front side section towards said crotch area and intersecting said second front seam before travelling into said crotch area of said main part and subsequently curving outwardly to cut through said second rear seam and slant outwardly through said second rear side section, said first and said second outer edges thereby being formed by one single respective separating process to impart an hour-glass contour to the disposable absorbent incontinence diaper.

2. The disposable absorbent incontinence diaper of claim 1, wherein said front and rear side sections are formed from or comprise a non-woven material.

3. The disposable absorbent incontinence diaper of claim 1, wherein said separating process is a cutting or punching process.

4. The disposable absorbent incontinence diaper of claim 1, wherein said first and said second outer edges have straight sections, straight sections extending at an inclination with respect to said longitudinal direction, and/or curved sections.

5. The disposable absorbent incontinence diaper of claim 1, wherein said first and said second outer edges exclusively comprise curved sections.

6. The disposable absorbent incontinence diaper of claim 1, wherein a tangent can be applied at any point of said first and said second outer edges.

7. The disposable absorbent incontinence diaper of claim 1, wherein a minimum curve radius of said first and said second leg openings is at least 5 mm.

8. The disposable absorbent incontinence diaper of claim 1, wherein said first and said second leg openings have curved sections with different curve radii.

9. The disposable absorbent incontinence diaper of claim 8, wherein said first elastic elements extend into neither said first and said second front side sections nor said first and said second rear side sections.

10. The disposable absorbent incontinence diaper of claim 1, further comprising first elastic elements having a component in said longitudinal direction and joined to said main part on a side next to longitudinal edges of said absorbent core.

11. The disposable absorbent incontinence diaper of claim 10, wherein said first elastic elements extend in a curved fashion along said first and said second leg openings.

12. The disposable absorbent incontinence diaper of claim 1, wherein said main part has an inner side and an outer side and said first closing means can be detachably fixed at least in some areas to both said outer side of said main part and also to said outer side of said first front side section, wherein said second closing means can also be detachably fixed at least in some areas to both said outer side of said main part and also to said outer side of said second front side section, for proper fixing of the disposable incontinence diaper to the user.

13. The disposable absorbent incontinence diaper of claim 12, wherein holding forces between said first closing means and said outer side of said first front side section are larger than holding forces between said first closing means and said outer side of said main part and holding forces between said second closing means and said outer side of said second front side section are larger than holding forces between said second closing means and said outer side of said main part.

14. The disposable absorbent incontinence diaper of claim 1, wherein holding forces for retention over a belly determined between said first or said second closing means or of said first or said second closing aids and an outer side of said main part are 20-57 N/25 mm.

15. The disposable absorbent incontinence diaper of claim 1, wherein holding forces for retention over a belly determined between said first or said second closing means or between said first or said second closing aids and an outer side of said first or said second front side sections are 58-90 N/25 mm.

16. The disposable absorbent incontinence diaper of claim 1, wherein said first and said second closing aids comprising Velcro hooks.

17. The disposable absorbent incontinence diaper of claim 16, wherein at least one of said first and said second closing means comprises an adhesive closing aid or an adhesive zone.

18. The disposable absorbent incontinence diaper of claim 1, wherein outer side of said main part is, at least in some areas or over a full surface thereof, formed by a non-woven material.

19. The disposable absorbent incontinence diaper of claim 1, further comprising a back sheet formed from a non-woven/film laminate, wherein a non-woven material comes to rest on an outside and a film material comes to rest on an inside facing said absorbent core such that said non-woven material forms an outer side of said main part.

20. The disposable absorbent incontinence diaper of claim 19, wherein said film material is single-layered or multi-layered, liquid-impermeable but breathable.

21. The disposable absorbent incontinence diaper of claim 1, wherein said the front and/or said rear side sections are formed by a non-woven material that is permeable to air and/or water vapor.

22. The disposable absorbent incontinence diaper of claim 1, wherein a basis weight of said front and/or said rear side sections is 15-60 g/m2, 20-45 g/m2, 25-40 g/m2 or 28-35 g/m2.

23. The disposable absorbent incontinence diaper of claim 1, wherein a breathability of said front and/or said rear side sections is larger than a breathability of a back sheet.

24. The disposable absorbent incontinence diaper of claim 1, wherein said first and said second front side sections and/or said first and said second rear side sections extend past a side edge of said main part by 10-40 cm.

25. The disposable absorbent incontinence diaper of claim 1, wherein said rear side sections have a surface extension which is larger than that of said front side sections, which is larger by at least 10% or is larger by at least 15%.

26. The disposable absorbent incontinence diaper of claim 1, wherein a length of said first and said second rear side sections or an extension thereof in the longitudinal direction of the diaper is at least 10 cm.

27. A method for producing the disposable incontinence diaper of claim 1 in a longitudinal direction thereof, the diaper having an hourglass-shaped main part, a front area, a rear area, and a crotch area which is disposed therebetween in a longitudinal direction and comes to rest between legs of a user, wherein the main part comprises an absorbent core, with rear side sections joined on both sides to the rear area, and front side sections joined on both sides to the front area, the rear and front side sections extending in a transverse direction past lateral longitudinal edges of the main part to connect the front area and the rear area to each other when the disposable incontinence diaper has been applied, wherein at least a side of the front and rear side sections facing the crotch area extends at an inclination to the longitudinal direction or is contoured, the front and rear side sections differing from each other with respect to at least one primary property selected from the group consisting of: type of material, basis weight, breathability, density, stretchability; closing force, surface extension, thickness, and color, the method comprising the steps of:
a) supplying a main part web in the longitudinal direction;
b) supplying a first side section web forming the rear side sections in the longitudinal direction;
c) supplying a second side section web forming the front side sections in the longitudinal direction;
d) separating the first and second sections from the first and second side section webs in a direction transverse to the longitudinal direction;
e) joining the first sections separated from the first side section web to an area of the main part web which forms one respective rear area of the disposable incontinence diaper for forming the rear side sections;
f) joining the second sections separated from the second side section web to an area of the main part web which forms one respective front area of the disposable incontinence diaper for forming the front side sections; and
g) forming, following steps a) through f), material cut-outs to obtain an inclined or curved shape of the front and rear side sections and the hourglass-shaped contour of the main part on both longitudinal sides of the disposable incontinence diaper for generating leg opening areas.

28. The method of claim 27, wherein the separating process of step g) also includes an area of front and rear lateral longitudinal edges of the main part.

29. The method of claim 27, wherein the separating process of step g) is a cutting or punching process.

30. The method of claim 27, wherein the separating process of step g) is performed along a line, which comprises straight and/or curved sections.

31. The method of claim 30, wherein the line exclusively comprises curved sections.

32. The method of claim 30, wherein the line extends starting from a point on a side edge of the front side sections of the disposable incontinence and curves to an inside towards the crotch area to a point of a front lateral longitudinal edge of the main part, then into the main part, then further through the crotch area of the main part and then in a curved fashion to an outside through a point of a front lateral longitudinal edge of the main part, and finally to a point on a side edge of the rear side sections.

33. The method of claim 32, wherein the line continuously extends through side section material or main part material to be separated.

34. The method of claim 27, wherein the separating process of step g) is performed by means of a knife drum.

35. The method of claim 27, wherein the disposable incontinence diapers are produced in such a fashion that, when being successively supplied in the longitudinal direction, a rear area of one disposable incontinence diaper is followed by a rear area of an adjacent disposable incontinence diaper and a front area of one disposable incontinence diaper is followed by a front area of an adjacent disposable incontinence diaper.

36. The method of claim 27, wherein each section that is separated transversely to the longitudinal direction forms front and rear side sections of two successively supplied disposable incontinence diapers.

37. The method of claim 27, further comprising joining closing means to the first side section web forming the rear side sections.

38. The method of claim 27, wherein two first and/or two second side section webs are formed by dividing a first material web and/or a second material web in the longitudinal direction.

39. The method of claim 27, wherein the main part web comprises a non-woven material and/or an absorbent core material and/or a material forming a back sheet, a film material, or a non-woven/film laminate material.

40. The method of claim 27, wherein the first and second sections are joined in a clocked fashion to an endless non-woven material web of the main part web, wherein the non-woven material web forms a side of the disposable incontinence diaper to be produced, which faces the user.

41. The method of claim 40, wherein at a time when the first and second sections are joined, the main part web consists essentially of the non-woven material web.

42. The method of claim 41, wherein the non-woven material web and the first and second sections that are joined thereto form a first composite, and an endless back sheet web, an endless film material, or non-woven/film material laminate web, which forms a back sheet of the diapers to be produced, forms a second composite together with discrete, successive, spaced-apart absorbent cores disposed on the back sheet web, wherein the first composite is joined to the second composite.

43. The method of claim 42, wherein the first composite is joined to the second composite in such a fashion that the absorbent cores are disposed between the back sheet web and the non-woven material web and the non-woven material web is directly connected to the back sheet web outside of a contour of the absorbent cores.

44. The method of claim 27, wherein the main part web is separated in a direction transverse to the longitudinal direction and extending through the first and second sections for forming singled disposable incontinence diapers.