WO2009136822A1

WO2009136822A1 - Hygienic undergarment and method for manufacturing the hygienic undergarment

Info

Publication number: WO2009136822A1
Application number: PCT/SE2008/050508
Authority: WO
Inventors: Carina Hedlund
Original assignee: Sca Hygiene Products Ab
Priority date: 2008-05-05
Filing date: 2008-05-05
Publication date: 2009-11-12

Abstract

The invention relates to an hygienic undergarment and a method for manufacturing a hygienic undergarment (1) from a substrate web (23). The hygienic undergarment (1) comprises, in a longitudinal direction (X), a front panel (3), a back panel (4) and a central panel (5) therebetween. The hygienic undergarment (1) is delimited in the longitudinal direction (X) by a first laterally (Y) extending edge (6) in the back panel (4) and a second laterally (Y) extending edge (7) in the front panel (3). Elastic means (18) are positioned on the substrate web (23) along a path (22; 22a, 22b, 22c) and first parts (20) of the substrate web (23) comprising a part of the elastic means (18) are removed in a transition area (X1; X2) between the front panel (3) and the central panel (5) and/or the back panel (4) and the central panel (5).

Description

TITLE

HYGIENIC UNDERGARMENT AND METHOD FOR MANUFACTURING THE HYGIENIC UNDERGARMENT

TECHNICAL FIELD

The invention refers to a hygienic undergarment and a method for manufacturing the hygienic undergarment from a substrate web.

BACKGROUND ART

In the field of absorbent articles such as diapers and incontinence articles, it is known to manufacture a diaper that allows for being formed about a user's body when in use. A typical absorbent article comprises a front panel, a back panel and a central panel therebetween, and also comprises a liquid impermeable backsheet and an absorbent body. The forming is made by the user or a helper placing the central panel in the groin area and then folding the front panel over the lower abdominal and the back panel over the lower back of the body. The front panel is then attached to the back panel over the each side of the user's body for forming side panels and leg openings. The leg openings are delimited by a curved edge portion comprised in the central panel. The curved edge portion comprises elastic means that have been arranged in such a way that when the absorbent article is put in place, the elastic means are elastically stretched and thus form a tight edge portion around the user's leg due to the retraction force of the elastic means. The tight edge portion is important for hindering leakage in the area.

When manufacturing such an absorbent article, various techniques are known, for example in WO9604874, but common for all is the trade off between speed in the production line, advanced products, advanced machines, and the cost for production. The speed is dependent on the type of equipment used and on how the absorbent article is assembled. One bottleneck in the production line is the step of applying the elastic means along the curved edge portion since the elastic means must have the correct tension, the correct position and must be attached to the backsheet (or any other suitable part of the absorbent article) with a suitable attachment means.

Furthermore, in most absorbent articles it is sometimes desirable not to have elastic means in the side panels since this would cause the side panels to crease. It is thus a problem to apply elastic means in a continuous process with high speed.

Hence, there exists a need for an improved method for manufacturing an absorbent article comprising leg elastics.

DISCLOSURE OF INVENTION

The invention relates to a method for manufacturing a hygienic undergarment from a substrate web. The hygienic undergarment comprises in a longitudinal direction, a front panel, a back panel and a central panel therebetween. The hygienic undergarment is delimited in the longitudinal direction by a first lateral edge in the back panel and a second lateral edge in the front panel and is delimited in the lateral direction by a first longitudinal edge having an extension from the first lateral edge to the second lateral edge and a second longitudinal edge having an extension from the first lateral edge to the second lateral edge.

The method comprises the steps of:

-positioning the elastic means on the substrate web along a path extending in the longitudinal direction from the first lateral edge in the back panel to the second lateral edge in the front panel, the path being curved in the central panel;

-removing first parts of the substrate web comprising a part of the elastic means in a transition area between the front panel and the central panel and/or the back panel and the central panel. The removal of the first parts eliminates the elastic means in the transition area which gives a better fit of the hygienic undergarment during application (putting it on) and during use. The removal of the first parts also allows for high speed when positioning the elastic means since the method according to the invention allows for the elastic means to be positioned in an easy pattern since the "wrong" part then is removed anyway. The "wrong" part means a part of the hygienic undergarment where elastic means are not wanted.

Here "hygienic undergarment" means a product intended to be used by a user for the purpose of taking care of bodily exudates such as urine, menstrual fluids or excrement. An absorbent article can be formed by an absorbent body being attached or integrated in or at least positioned in connection to the substrate web in the production line; or can be formed by the absorbent body being added to the hygienic undergarment before use. In the former case the hygienic undergarment together with the absorbent article forms an absorbent article such as a diaper, incontinence product or any other suitable absorbent article. In the latter case the substrate web has been formed in the production line to comprise the panels described above and the substrate web has then been cut into separate hygienic undergarments and the absorbent body is intended to be applied by the user in the hygienic undergarment before use. The hygienic undergarment is here used as a supporting garment for the absorbent body. The supporting garment can for example be used as a supporting garment in a swim ware or as a support garment for an absorbent article such as a diaper, incontinence products or the like. It should be noted that the hygienic undergarment may be formed from a material being suitable as a backsheet or may comprise a number of different layers, for example an absorbent body positioned on a liquid impermeable backsheet. In addition to the hygienic undergarment and the absorbent body, the absorbent article may comprise a number of different layers for example one or more topsheets arranged to be worn closest to the body of a user. The absorbent body is then positioned between the backsheet, i.e. the hygienic undergarment, and the topsheet.

If the hygienic undergarment comprises a topsheet, the topsheet may be comprised in the substrate web and the elastic means may be positioned on the topsheet, i.e. the substrate web, before the topsheet is attached to the backsheet.

In a first embodiment of the invention the removal of the first parts forms the two curved edge portions comprising the elastic means in addition to the removal of the part of the elastic means. Hence, the removal of the first parts forms a curved part comprised in the first longitudinal edge and a corresponding curved part comprised in the second longitudinal edge.

In a second embodiment of the invention the substrate web already comprises the two curved edge portions comprising the elastic means and wherein the removal of the first parts are made in the curved edge portions.

One benefit of the invention according to both embodiments is that the elastic means can be continuously positioned on the substrate web in a simple manner since the elastic means can be removed in the transition area.

According to the invention, the hygienic undergarments are manufactured in a continuous process, wherein the substrate web is a continuous web travelling in a machine direction and comprising a series of hygienic undergarments. According to one example the undergarments are arranged in the following pattern: the front panel of a first hygienic undergarment is followed by the front panel of a second hygienic undergarment and the back panel of the second hygienic undergarment is followed by the back panel of a third hygienic undergarment; or arranged in the following pattern: the front panel of a first hygienic undergarment is followed by the back panel of a second hygienic undergarment and the front panel of the second hygienic undergarment is followed by the back panel of a third hygienic undergarment. According to another example the longitudinal edges of the hygienic undergarments are positioned next to each other in the substrate web.

According to one example of the invention the path starts at a first position defined by the lateral direction and the longitudinal direction when the hygienic undergarment is in an essentially flat state, wherein the path stops at a second position defined by the lateral direction and the longitudinal direction when the hygienic undergarment is in an essentially flat state.

According to one example, the second position is essentially equal to the first position in the cross-machine direction. The starting point for a lay-out-device must be essentially the same for each new hygienic undergarment in the continuous process in order to get essentially identical products.

It is a problem to apply elastic means in a continuous process with high speed when trying to avoid elastic means in the transition area since there must be either a very difficult change in direction for the elastic web in the transition area or the lay-out-device device used must position elastic means batch wise only in the curved path. The first alternative demands advanced machines and/or a slow pace, and the second alternative gives a slow operation.

One example of a machine that can be used for positioning of the elastic means thanks to the invention is a simple lay-out-device working in the lateral direction only and is arranged to vary the lateral position of the elastic means. Since the substrate web moves in the machine direction at the same time as the lay-out-device moves in the cross-machine direction, the elastic means can be positioned in a curved pattern.

The invention also relates to a hygienic undergarment comprising, in a longitudinal direction, a front panel, a back panel and a central panel therebetween. The hygienic undergarment is delimited by a first lateral edge in the back panel and a second lateral edge in the front panel. The central panel comprises two curved edge portions comprising elastic means. The invention is characterized in that a part of the elastic means in the curved edge portions has been removed by removal of first parts of the hygienic undergarment comprising a part of the elastic means in a transition area between the front panel and the central panel and/or the back panel and the central panel.

The benefit of the invention is an improved fit of the hygienic undergarment during application and use.

BRIEF DESCRIPTION OF DRAWINGS

The invention will be described below with reference to a number of drawings, in which:

Figure 1 schematically shows a hygienic undergarment, according to the invention, in the form of an absorbent article, such as a diaper or incontinence article;

Figure 2 schematically shows a first embodiment of the removal of the first part according to the invention;

Figure 3 schematically shows an enhanced part of figure 2;

Figure 4 schematically shows a second embodiment of the removal of the first part according to the invention;

Figure 5 schematically shows a third embodiment of the invention of the removal of the first part;

Figure 6 schematically shows an enhanced part of figure 5;

Figure 7 schematically shows a fourth embodiment of the invention;

Figure 8 schematically shows a continuous production line for the absorbent article according to the invention; Figure 9 schematically shows a block diagram for the method according to the invention;

Figure 10 schematically shows removal of the first part according to figure 3 on a substrate web without an absorbent body;

Figure 11 schematically shows removal of the first part according to figure 4 on a substrate web without an absorbent body, and in which;

Figure 12 schematically shows a continuous production line for the absorbent article according to the invention.

EMBODIMENT(S) OF THE INVENTION

Figure 1 shows a hygienic undergarment 1 in the form of an absorbent article

2, such as a diaper or incontinence article, manufactured with a method according to the invention. With reference to figures 1-9, the description of the hygienic undergarment 1 and the method for manufacturing the hygienic undergarment 1 is made with reference to the absorbent article 2, but it is to be understood that the description is valid also for the hygienic undergarment

1 without any absorbent body.

The absorbent article 2 comprises, in a longitudinal direction X, a front panel

3, a back panel 4 and a central panel 5 therebetween. The absorbent article

2 is in the longitudinal direction delimited by a first lateral edge 6 in the back panel 4 and a second lateral edge 7 in the front panel 3 The absorbent article

2 is in a lateral direction Y delimited by a first longitudinal edge 8 having an extension from the first lateral edge 6 to the second lateral edge 7 and a second longitudinal edge 9 having an extension from the first lateral edge 6 to the second lateral edge 7 on each side of the absorbent article 2. The front panel 3 comprises, in the lateral direction Y, two first side portions 10 and a first mid portion 11 therebetween. The back panel 4 comprises, in the lateral direction Y, two second side portions 12 and a second mid portion 13 therebetween. Figure 1 shows that the absorbent article 2 comprises a backsheet 14, a topsheet 15 and an absorbent body 16 therebetween. The backsheet 14 is advantageously liquid impermeable, but may be breathable. Breathable means that moist air can diffuse through the backsheet 14 from within the absorbent article 2 to the ambient air but is also liquid impermeable. The backsheet 14 may comprise one or many layers of the same or different materials. In figure 1 the backsheet is formed from a substrate web (ref. 24 in fig. 2) in a process for producing the hygienic undergarment.

The division of the absorbent article 2 into panels and portions does not refer to strict physical parameters as such, but are used in order to facilitate the description of the invention. The division may thus depend on the design of the absorbent article. In figures 1-11 the panels refer to the backsheet.

However, the absorbent body 16 may at least partly be comprised in the panels 2, 4, 5 as can be seen in figures 1-8 or may be added to the backsheet after manufacture of the hygienic undergarment as can be seen in figures 10 and 11.

Figure 1 shows that the central panel 5 comprises two curved edge portions 17 comprising elastic means 18. The two curved edge portions 17 are comprised in the first longitudinal edge 8 and the second longitudinal edge 9 respectively. The elastic means 18 have been applied on the backsheet 14 when the absorbent article 2 has been brought into a splayed position. The elastic means 18 has also been attached to the backsheet in the central panel with suitable attachment means, for example glue, welding, mechanical bonding, etc. Figure 1 shows the elastic means 18 in a contracted state which causes the central panel 5 to get creased. The creased curved edge portions 17 allows for the absorbent article 2 to achieve a snug fit about a user's leg when used, because the elastic means 18 and the creased backsheet 14 can be stretched about the user's leg when put on and the contraction force of the elastic means 18 forces the curved edge portion 17 to a snug fit that hinders leakage. In order to allow for the curved edge portions 17 to be creased, the elastic means 18 may be applied on the backsheet in a pre-tensioned state when the absorbent article 2 has been brought into a splayed position. However, the elastic means 18 may be applied on the backsheet in a relaxed state but is then manipulated, for example by heat or light or any other suitable method, in such a way that the elastics means shrinks or changes state in another way so that the elastic means retracts and creates the creases.

The absorbent article 2 is intended to be formed by the user or a helper by placing the central panel 5 in the groin area of the user and then folding the front panel 3 over the lower abdominal and the back panel 4 over the lower back of the body. The front panel 3 is then attached to the back panel 4 over the each side of the user's body for forming side panels 19 and leg openings. The side panels 19 are formed by a part of the back panel and a part of the front panel being attached to each other. In figure 1 the first side portions 10 are supposed to be attached to the second side portions 13, or vice versa, for forming the side panels 19. Each leg opening is delimited by each curved edge portion 17 comprised in the central panel 5.

One important part of the absorbent article 2 according to the invention is that the elastic means 18 shall not exist or at least shall not apply any forces on the absorbent article 2 in the transition area X1 between the central panel 5 and the front panel 3. The reason is that the absorbent article 2 does not conform well against the body of the user if the elastic means 18 applies forces in the transition area X1. It should be noted that if the elastic means 18 are positioned in the transition area X1 without being fastened, the transition area X1 is subject to external forces during use, due to body movement, so that the elastic means 18 are affected and then involuntarily applies forces in the transition area X1 when the user moves. Furthermore, another disadvantage of having elastic means 18 present in the transition area X1 is that the elastic means 18 will cause the front panel 3 to wrinkle during the step of putting on the absorbent article 2. In figure 1 the elastic means 18 do not exist in the transition area X1 because that a part of the elastic means 18 in the curved edge portions 17 have been removed by removal of first parts (reference number 20 in figures 2-8 and 10- 12) of the absorbent article 2 comprising a part of the elastic means 18 in the transition area X1.

Figures 2-3 schematically show one embodiment of the removal of the first parts 20 according to the invention. Figure 3 is an enhancement of figure 2 showing one absorbent article 2, and where it is shown that the removal of the first parts 20 form the two curved edge portions 17 comprising the elastic means 18 in addition to the removal of the part of the elastic means 18 in the transition area X1.

Figure 2 shows the absorbent article in a splayed position. In figure 2 "splayed" refers to the hygienic undergarment 1 being in an essentially flat state, but "splayed" also refers to the hygienic undergarment being in an essentially flat state but bent over an axis, for example a roll.

Figure 2 shows that elastic means 18 are laid out on the hygienic undergarment 1 by use of a lay-out-device 21 along a path 22 extending essentially in the longitudinal direction X. The path 22 starts at a first position P1 defined by the lateral direction Y and the longitudinal direction X when the absorbent article 2 is in an essentially flat state, wherein the path 22 stops at a second position defined by the lateral direction Y and the longitudinal direction X when the absorbent article is in an essentially flat state, and wherein the second position P2 is essentially equal to the first position P1.

Figure 2 shows that the back panel 4 comprises two parallel straight paths 22a and the front panel 3 comprises two parallel straight paths 22b and that the central panel 5 comprises two essentially identical curved paths 22c for forming leg elastics along the longitudinally extending edges 8, 9 of the central panel 5. The straight paths 22a, 22b are positioned in that part of the back panel 4 and front panel 3 that are intended to be used as side panels (ref. 19, fig. 1 ) as described in connection to figure 1. In figures 1 and 2 the straight paths 22a, 22b do not comprise attachment means for the elastic means 18 since in some embodiments of the invention it is not desirable to have creased side panels. In figure 1 the path 22 makes a turn in the first part 20 in order to terminate the curved path 22c in the central panel 5 and to follow the straight path 22b in the front panel 3.

Figure 2 shows a part of a continuous substrate web 23 comprising two hygienic undergarments 1 with an absorbent body 16 positioned on the substrate web 23 for manufacturing of an absorbent article 2. The substrate web 23 runs in a machine direction X and the elastic means are positioned on the substrate web by the lay-out-device performing lateral Y movement in order to adjust the position of the elastic means along the path 22. The movement of the substrate web 23 in the machine direction X together with the lateral adjustment of the elastic means 18 give the possibility for the lay- out-device to follow both straight 22a, 22b and curved 22c paths.

Figure 2 shows that the first parts 20 are removed by a removing device 24. The removing device 24 may use any known technique for separating the first part 20 from the substrate web 23, for example, mechanical cutting, milling, shearing, etc., or use of laser or ultrasonic techniques or any other suitable techniques. The substrate web 23 may for example be guided between a cutting roll and an anvil roll.

Figure 4 shows a second embodiment of the removal of the first part 20 according to the invention. Figure 4 shows that the absorbent article 2 already comprises two curved edge portions 17 comprising the elastic means 18 when the first parts 20 are removed. Hence, the removal of the first parts 20 is made in the already existing curved edge portions 17.

Figure 5 shows a third embodiment of the invention of the removal of the first parts 20. As in figure 3, figure 5 shows that the removal of the first parts 20 forms the two curved edge portions 17 comprising the elastic means 18 in addition to the removal of the part of the elastic means 18 in the transition area X1. Furthermore, in figure 5 the removal of the first part also removes the elastic means 18 in a second transition area X2 between the central panel 5 and the back panel 4.

Figure 6 is an enhanced part of figure 5 showing one absorbent article 2.

Figure 7 shows a fourth embodiment of the invention. As in figure 4, figure 7 shows that the absorbent article 2 already comprises two curved edge portions 17 comprising the elastic means 18 when the first parts 20 are removed. Hence, the removal of the first parts 20 are made in the already existing curved edge portions 17. In figure 7 the removal of the first parts 20 comprises removal of several first parts 20 for removing the elastic means 18 in the first transition area X1 and in a second transition area X2 between the central panel and the back panel.

Figure 8 shows a continuous production line for the absorbent article 2 according to the invention.

Figure 8 shows that the absorbent articles 2, i.e. the hygienic undergarments 1 , are manufactured in a continuous process comprising a continuous web 23 travelling in a machine direction X and comprising a series of absorbent articles 2 arranged in the following pattern: the front panel 3 of a first absorbent article 2 is followed by the back panel 4 of a second absorbent article 2 and the front panel 3 of the second absorbent article 2 is followed by the back panel 4 of a third absorbent article 2. The series of absorbent articles 2 can also be arranged in the following pattern: the front panel 3 of a first absorbent article 2 is followed by the front panel 3 of a second absorbent article 2 and the back panel 4 of the second absorbent article 2 is followed by the back panel 4 of a third absorbent article 2. A combination of the two series described is also possible.

The elastic means 18 are positioned by a lay-out-device 21 varying the lateral position of the elastic means and the substrate web 23 is separated into separate absorbent articles 2 by a separation device 24. Figure 8 shows that the hygienic undergarment 1 is manufactured in three consecutive steps; the elastic means 18 are positioned on the substrate web, the first parts 20 are removed and the substrate web 23 is separated into separate hygienic undergarments 1/absorbent articles 2.

With reference to figure 8, figure 9 shows a block diagram for the method according to the invention.

The method comprises the steps of:

Block 901 :

-positioning elastic means along a path extending in the longitudinal direction from the first lateral edge in the back panel to the second lateral edge in the front panel, the path being curved in the central panel for forming leg elastics;

Block 902:

-removing first parts of the absorbent article comprising a part of the elastic means in a transition area between the front panel and the central panel and/or the back panel and the central panel.

Block 903:

-separating the substrate web into separate hygienic undergarments/absorbent articles

The method according to the invention is not limited to these three steps 901- 903, but additional steps can be added, for example the positioning of the absorbent body may be made before, during or after any of the three steps 901-903. Furthermore, the second step 902 and the third step 903 may be done at the same time, or the third step 903 may be done before the second step 902. One further example of an additional step is positioning a topsheet over the absorbent body. Figure 10 schematically shows removal of the first part 20 according to figure 3 on a substrate web 23 without an absorbent body. Figure 10 thus shows manufacturing of the hygienic undergarment 1 according to any one of figures 1-9 but with the difference that the absorbent body is not present in the hygienic undergarment 1. The hygienic undergarment 1 can be used as a support garment for an absorbent body being positioned in the hygienic undergarment 1 by a user before use. The hygienic undergarment 1 can also be used as a backsheet in an absorbent article according to figures 1-9 where the absorbent body has been positioned in the hygienic undergarment during the manufacturing process of the absorbent article.

Figure 11 schematically shows removal of the first part according to figure 4 on a substrate web without an absorbent body. Reference is made to figures 1-10 with regard to method for manufacturing, use and advantages.

Figure 12 schematically shows a continuous production line for the hygienic undergarment 1 according to the invention. Figure 12 shows an absorbent article 2 as described in connection to any one of, or a combination of, figures 1-11. In figure 12 the hygienic undergarments 1 are positioned side by side in the substrate web 23, but figures 1-11 shows the lateral edges 6, 7 positioned side by side. In figure 12 "side by side" refers the longitudinal edges 8, 9 of the hygienic undergarments 1 being positioned next to each other in the substrate web 23. One scenario is that the first longitudinal edge 8 of a first hygienic undergarment 1 is positioned next to the second longitudinal edge 9 of a second hygienic undergarment 1. Hence, the front panel 3 of the first hygienic undergarments 1 is positioned next to the front panel 3 of the hygienic undergarments 1 and the described pattern repeats itself along the substrate web in the machine direction Y. Another scenario is that the first longitudinal edge 8 of a first hygienic undergarment 1 is positioned next to the first longitudinal edge 8 of a second hygienic undergarment 1 and that the second longitudinal edge 9 of the second hygienic undergarment 1 is positioned next to the second longitudinal edge 9 of a third hygienic undergarment 1. Hence, the front panel 3 of the first hygienic undergarments 1 is positioned next to the back panel 4 of the hygienic undergarments 1 and that the back panel 4 of the hygienic undergarments 1 is positioned next to the front panel 3 of the third hygienic undergarment 1 , and the described pattern repeats itself along the substrate web in the machine direction Y.

In figure 12 the lay out device 21 positions the elastic means 18 along two paths 22, each starting in one side portion 10, 12, traversing the central panel 5 in the lateral direction and continue in side portion 10, 12 on the other side, in the lateral direction Y of the hygienic undergarment 1. Figure 12 shows that each elastic means 18 is laid out in a Zigzag pattern starting in the back panel 4 and finishing in the front panel 3, or starting in the front panel 3 and finishing in the back panel 4. In figure 12, the path 22 is essentially straight 22a in the back panel and essentially straight 22b in the front panel and curved 22c in the central panel. Figure 12 also shows that the elastic means 18 crosses each other in the central panel 5, and the reason is to obtain a flow in the lay out process in order to create the curved leg elastics being described in connection to figures 1-11.

The path 22 of the elastic means may be U-shaped (not shown), wherein the path 22 is essentially straight 22a, 22b in the front panel 3 and the back panel 4 and curved 22c in the central panel 5 and wherein one path starts and finishes in the back panel 4 and the other path starts and finishes in the front panel 3.

The path 22 of the elastic means may be X-shaped (not shown), wherein the path 22 is essentially straight 22a, 22b, curved or straight and inclining in the front panel 3 and the back panel 4 and curved 22c in the central panel 5 and wherein one path starts in the back panel 4 and finishes in the front panel 3 or vice versa, and wherein the other path starts in the back panel 4 and finishes in the front panel 3 or vice versa. The two paths 22 cross each other in the central panel. As mentioned in connection to figures 1-11 , the first parts 20 comprising a part of the elastic means 18 in the first transition area X1 and/or the second transition area X2 (not shown in figure 12) are removed according to the invention described in connection to any one, or a combination of, figures 1- 11.

The production line in figure 12 differs from the production line described in figures 1-11 with regard to orientation of the hygienic undergarments in the substrate web relative the machine direction Y, which necessitates a different lay out device 21 compared to figures 1-11. In figure 12, the lay out device may comprise two or more lay out devices that can operate both in the longitudinal direction X, here cross-machine direction, and in the lateral direction Y, here machine direction, if a part of the path shall be straight in the longitudinal direction. However, the same type of lay out devices described in connection to figures 1-11 can be used in the process according to figure 12 if diagonal or curved patterns can be allowed in the front panel and the back panel. In figure 12 the lay out device 21 may comprise four lay out devices working in pairs. The two pairs are then advantageously used in such a way that they take turns for laying out the elastic means, i.e. one pair laying out elastic means on one hygienic undergarment and the second pair on the next hygienic undergarment.

The method described in connection to figures 1-12 has the advantage that simple machines can be used in order to position the elastic means. The reason is that the elastic means can be continuously positioned on the substrate web in a simple pattern since the elastic means can be removed in the first and/or the second transition area according to the invention.

The invention is not limited to the embodiment shown in figures 1-12, but may be varied within the scope of the claims. For example, the elastic means may comprise one or several elastic threads of the same or different width, height, girth and material; and the elastic means can apply different retraction forces along different portions of the path for forming the hygienic undergarment.

Claims

ZUUb-UD-UJ18CLAIMS

1. A method for manufacturing a hygienic undergarment (1 ) from a substrate web (23), the hygienic undergarment (1 ) comprising, in a longitudinal direction (X), a front panel (3), a back panel (4) and a central panel (5) therebetween, the hygienic undergarment (1 ) being delimited in the longitudinal direction (X) by a first laterally (Y) extending edge (6) in the back panel (4) and a second laterally (Y) extending edge (7) in the front panel (3),

the method comprises the steps of:

-positioning elastic means (18) on the substrate web (23) along a path (22; 22a, 22b, 22c) extending in the longitudinal direction (X) from the first lateral edge (6) in the back panel (4) to the second lateral edge (7) in the front panel (3), the path (22; 22c) being curved in the central panel (5) for forming leg elastics during use;

-removing first parts (20) of the substrate web (23) comprising a part of the elastic means (18) in a transition area (X1 ; X2) between the front panel (3) and the central panel (5) and/or the back panel (4) and the central panel (5).

2. A method according to claim 1 , wherein the substrate web (23) is brought into a splayed position before positioning the elastic means (18);

3. A method according to claim 1 or 2, wherein the removal of the first parts (20) forms two curved edge portions (17) comprising the elastic means (18) in addition to the removal of the part of the elastic means (18).

4. A method according to claim 1 , wherein the substrate web (23) comprises the two curved edge portions (17) comprising the elastic means (18) and wherein the removal of the first parts (20) are made in the curved edge portions (17).

5. A method according to any one of the previous claims, wherein the path (22; 22a, 22b, 22c) starts at a first position (P1 ) defined by the lateral direction (Y) and the longitudinal direction (X) when the hygienic undergarment (1 ) is in an essentially flat state, wherein the path (22; 22a, 22b, 22c) stops at a second position (P2) defined by the lateral direction (Y) and the longitudinal direction (X) when the hygienic undergarment (1 ) is in an essentially flat state, and wherein the second position (P2) is essentially equal to the first position (1 ) in the lateral direction (Y).

6. A method according to any one of the previous claims, wherein the back panel (4) comprises a straight path (22a) and the front panel (3) comprises a straight path (22b), and wherein the path (22; 22c) makes a turn in the first part (20) in order to terminate the curved path (22c) in the central panel (5) and to follow the straight path (22b) in the front panel (3).

7. A method according to any one of the previous claims, wherein the positioning of the elastic means (18) are made in two paths (22; 22a, 22b, 22c) for forming leg elastics along both the longitudinally extending edges (8, 9) of the central panel (5).

8. A method according to any one of the previous claims, wherein the hygienic undergarment (1 ) comprises attachment means for the elastic means (18) only in the curved path (22; 22c).

9. A method according to any one of the previous claims, wherein the hygienic undergarment (1 ) are manufactured in a continuous process, wherein the substrate web (23) is a continuous web travelling in a machine direction (X) and comprising a series of hygienic undergarments (1 ) arranged in the following pattern: the front panel (3) of a first hygienic undergarment (1 ) is followed by the front panel (3) of a second hygienic undergarment (1 ) and the back panel (4) of the second absorbent article (2) is followed by the back panel (4) of a third hygienic undergarment (1 ); or arranged in the following pattern: the front panel (3) of a first hygienic undergarment (1 ) is followed by the back panel (4) of a second hygienic undergarment (1 ) and the front panel (3) of the second hygienic undergarment (1 ) is followed by the back panel (4) of a third hygienic undergarment (1 ); or wherein the first and second longitudinal edges (8, 9) of the hygienic undergarments (1 ) are positioned next to each other in the substrate web (23); or wherein the first longitudinal edges (8) of a first and second hygienic undergarment (1 ) are positioned next to each other in the substrate web (23) and wherein the second longitudinal edges (8) of the second and a third hygienic undergarment (1 ) are positioned next to each other in the substrate web (23).

10. A method according to claim 10, wherein the elastic means (18) is positioned by a lay-out-device (21 ) varying the lateral position of the elastic means (18).

11. A method according to any one of the previous claims, wherein the elastic means (18) are positioned in a pre-tensioned state.

12. A method according to any one of the previous claims, wherein the substrate web (23) constitute a part of a backsheet 14 in the hygienic undergarment (1 ).

13. A method according to any one of the previous claims, wherein the substrate web (23) constitute a part of a topsheet (15) in the hygienic undergarment (1 ).

14. A method according to any one of the previous claims, wherein an absorbent body (2) is positioned on the substrate web (23).

15. An hygienic undergarment 1 comprising, in a longitudinal direction, a front panel (3), a back panel (4) and a central panel (5) therebetween, the hygienic undergarment (1 ) being delimited by a first lateral edge (6) in the back panel (4) and a second lateral edge (7) in the front panel (3), the central panel (5) comprising two curved edge portions (17) comprising elastic means, characterized in that a part of the elastic means (18) in the curved edge portions (17) has been removed by removal of first parts (20) of the hygienic undergarment (1 ) comprising a part of the elastic means (18) in a transition area (X1 ; X2) between the front panel (3) and the central panel (5) and/or the back panel (4) and the central panel (5).