MANUFACTURING METHOD FOR AN ABSORBENT ARTICLE COMPRISING A POCKET AND ABSORBENT ARTICLE BEING PRODUCIBLE THEREBY

Abstract

A manufacturing method is provided. According to a first step (100), the method comprises providing a backsheet layer, a cover strip layer, and an absorbent core layer in order to manufacture an absorbent article comprising a pocket being accessible from the non-absorbent side of the absorbent article. Then, according to a second step (101), the method comprises cutting an opening into the backsheet layer. In this context, the cutting is speed-synchronized with respect to the provision of the backsheet layer in such a manner that the opening is placed at the same position for every absorbent article. Furthermore, according to a third step (102), the method comprises placing the cover strip layer between the backsheet layer and the absorbent core layer.

Claims

1. A manufacturing method for manufacturing an absorbent article (17, 18) comprising a backsheet layer (11) on the garment facing side of said absorbent article (17, 18) and a pocket being accessible from the garment facing side of the absorbent article (17, 18) through an opening of the backsheet layer (11), the manufacturing method comprising the steps of: providing a backsheet layer (11), a cover strip layer (12), and an absorbent core layer (13), cutting an opening into the backsheet layer (11), and placing the cover strip layer (12) between the backsheet layer (11) and the absorbent core layer (13), wherein the cutting is speed-synchronized with respect to the provision of the backsheet layer (11) in such a manner that the opening is placed at the same position (21) for every absorbent article (17, 18) in a sequence of absorbent articles, or wherein in the case that the absorbent article (17, 18) further comprises a pattern on the backsheet layer (11), the backsheet layer (11) is speed-controlled with respect to the positioning of the pattern in such a manner that the opening is placed at the same position (21) relatively to the pattern for every absorbent article (17, 18) in a sequence of absorbent articles.

2. The manufacturing method according to claim 1, wherein the pattern is arranged in such manner onto the backsheet layer (11) that the same portion of the pattern is positioned in the same way for every absorbent article (17, 18), and/or wherein the pattern comprises a conductive pattern especially being applied onto the backsheet layer (11) by means of printing and/or spraying and/or laminating conductive material onto the backsheet layer (11) and/or a non-conductive pattern especially being applied onto the backsheet layer (11) by means of printing and/or embossing.

3. The manufacturing method according to claim 1 or 2, wherein the pattern comprises an ink, preferably a carbon-based ink and/or a conductive polymer-based ink, wherein the ink especially comprises at least one of graphene, graphite, nano-carbon-tubes, polyacetylene, polypyrrole, polyaniline and copolymers thereof, poly(pyrrole)s (PPY), polyanilines (PANI), poly(thiophene)s (PT), poly(p-phenylene sulfide) (PPS), poly(p-phenylene) (PPP), Poly(acetylene)s (PAC), Poly(p-phenylene vinylene) (PPV), poly(3,4-ethylenedioxythiophene) (PEDOT), poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), or any combination thereof.

4. The manufacturing method according to any of the claims claims 1 to 3, wherein the pattern is applied onto the backsheet layer (11) prior to converting the backsheet layer (11), or wherein the pattern is applied within the same or another manufacturing process onto the backsheet layer (11) with the aid of a pattern application unit, wherein the pattern application unit is especially synchronized at least with the process step of cutting the opening into the backsheet layer (11).

5. The manufacturing method according to any of the claims 1 to 4, wherein with the aid of a visual control unit, the positioning of the pattern on the backsheet layer (11) relatively to the opening of said backsheet layer (11) is visually controlled to determine a first offset value (x) and/or a second offset value (y) by processing visual inspection data, wherein the first offset value (x) is especially adapted to quantify the deviation of said positioning in converting direction of the backsheet layer (11), and/or wherein the second offset value (y) is especially adapted to quantify the deviation of said positioning in the direction perpendicular to the converting direction of the backsheet layer (11), and/or wherein the visual control unit especially comprises a camera and/or an optical sensor.

6. The manufacturing method according to claim 5, wherein the first offset value (x) is used to drive the speed-control of the backsheet layer (11).

7. The manufacturing method according to claim 5 or 6, wherein the second offset value (y) is used to move the backsheet layer (11) with the pattern relatively to the opening and relatively to the cover strip layer (12) in a direction perpendicular to the converting direction in such a manner that the second offset value (y) is reduced towards zero, wherein the relative positioning of said backsheet layer (11) is especially driven by means of a web guiding device for the backsheet layer (11) and/or by a web guiding device for the cover strip layer (12) and/or by a device to move a corresponding cutting device for cutting the opening in a direction perpendicular to the converting direction.

8. The manufacturing method according to any of the claims 1 to 7, wherein the opening of the backsheet layer (11) is cut with the aid of at least one of a rotary knife, a cutting die, a punching tool, a laser cutting tool, a water jet cutting tool, or any combination thereof, and/or wherein the cover strip layer (12) is placed between the backsheet layer (11) and the absorbent core layer (13) in such a manner that the opening of the backsheet layer (11) is at least partly covered by the cover strip layer (12).

9. The manufacturing method according to any of the claims 1 to 8, wherein the width of the cover strip layer (12) is less than the width of the backsheet layer (11) and/or the width of the absorbent article (13), and/or wherein the width of the cover strip layer (12) is wider than the opening of the backsheet layer (11), and/or wherein the cover strip layer (12) comprises or is a liquid barrier.

10. The manufacturing method according to any of the claims 1 to 9, wherein the cover strip layer (12) is non-intermittently placed, or wherein the cover strip layer (12) is intermittently placed, wherein the intermittent placement of the cover strip layer (12) comprises the additional step of cutting the cover strip layer (12) in such a manner that the length of the cover strip layer (12) is less than the length of the backsheet layer (11) and/or the length of the absorbent article (13).

11. The manufacturing method according to any of the claims 1 to 10, wherein the manufacturing method comprises the step of sealing at least two edges, preferably four edges, of the cover strip layer (12) to the backsheet layer (11) especially in such a manner that the sealing pattern is surrounding the opening to form the pocket between said backsheet layer (11) and said cover strip layer (12).

12. The manufacturing method according to claim 11, wherein the step of sealing comprises an adhesive application and/or a welding, preferably an ultrasonic welding, application.

13. The manufacturing method according to any of the claims 1 to 12, wherein the backsheet layer (11) comprises at least one outer layer (11a) and at least one inner layer (11b) being closer to the cover strip layer (12) than the at least one outer layer (11a), wherein at least two, preferably all, layers (11a, 11b) of the backsheet layer (11) are especially laminated to each other, and/or wherein the at least one outer layer (11a) especially covers at least a part of the surface of the at least one inner layer (11b) and/or especially at least surrounds the opening of the backsheet layer (11).

14. The manufacturing method according to claim 10, wherein the at least one outer layer (11a) comprises a substrate, preferably a non-woven substrate, and/or wherein the at least one inner layer (11b) comprises a film, preferably a non-permeable film.

15. An absorbent article comprising a backsheet layer, a cover strip layer, an absorbent core layer, and a pocket being accessible from the non-absorbent side of the absorbent article, the absorbent article being producible by the steps of a method of one of the claims 1 to 14.

Description

[0034] FIG. 1 shows a flow chart of an exemplary embodiment of the inventive manufacturing method;

[0035] FIG. 2 shows a first exemplary embodiment of a production line in accordance with the invention;

[0036] FIG. 3 shows a second exemplary embodiment of a production line in accordance with the invention;

[0037] FIG. 4 shows four exemplary embodiments of forming the pocket by sealing the cover strip to the backsheet in accordance with the invention;

[0038] FIG. 5 shows four exemplary cases of alignment or misalignment with respect to the elements of the absorbent article;

[0039] FIG. 6 shows an exemplary embodiment of an absorbent article with a pattern of conductive and non-conductive elements in combination in accordance with the invention; and

[0040] FIG. 7 shows a flow chart of an exemplary embodiment of the inventive manufacturing method in greater detail.

[0041] Firstly, FIG. 1 shows a flow chart of an embodiment of the inventive manufacturing method. According to a first step 100, the method comprises providing a backsheet layer, a cover strip layer, and an absorbent core layer in order to manufacture an absorbent article comprising a pocket being accessible from the non-absorbent side of the absorbent article. Then, according to a second step 101, the method comprises cutting an opening into the backsheet layer. In this context, the cutting is speed-synchronized with respect to the provision of the backsheet layer in such a manner that the opening is placed at the same position for every absorbent article. Furthermore, according to a third step 102, the method comprises placing the cover strip layer between the backsheet layer and the absorbent core layer.

[0042] With respect to the absorbent article, especially the pocket thereof, it is noted that such an absorbent article may exemplarily be used within the following usage scenario:

[0043] Equipping an absorbent article with an integrated sensor and providing an electronic device that needs to be attached to the product to allow the read-out of sensor data. The electronic device needs to be in conductive interconnection to the printed sensor inside the absorbent article and it needs to be securely attached to allow a reliable interconnection and to be protected against unintended loss or removal of the device. For this purpose, the absorbent article may preferably comprise the pocket, wherein at least a part of the electronic device can be inserted and that allows a reliable attachment of the device.

[0044] Generally, the invention is about the process that allows the formation of the pocket for an absorbent article on a scale of mass production. For instance and as an advantage, the construction may especially allow the conductive interconnection between the inserted device and the printed sensor of the absorbent article. Further advantageously, the construction is cost efficient and the manufacturing method or process, respectively, does not sacrifice the speed of a production line.

[0045] Now, the manufacturing method will be explained in greater detail with the aid of the first embodiment of a production line according to FIG. 2 and the second embodiment of a production line according to FIG. 3 in the following. In this context, it might particularly advantageous if at least one, exemplarily each, of the backsheet layer 11, the cover strip layer 12, and the absorbent core layer 13 is provided with the aid of an unwinder as illustrated by FIG. 2 and FIG. 3.

[0046] As it can further be seen from FIG. 2 or FIG. 3, respectively, the process is adding the layer with the cover strip 12 that comes from the corresponding unwinder and that is sealed to the inner side of the backsheet 11, so that the cover strip is placed between the backsheet 11 and the absorbent core 13 (or any other layer that is underneath the backsheet and above the core). In this context, the width of the cover strip 12 is less than the full width of the product or the absorbent article, respectively, but is wider than the opening of the pocket so that, for example, the above-mentioned device fits into the pocket and is surrounded by it, at least partially.

[0047] With respect to the first and the second embodiment of a production line, it is noted that the cover strip or the cover strip layer 12, respectively, can be added with the full length of the product or the absorbent article, respectively (non-intermittent application according to FIG. 2). As an alternative, the cover strip or the cover strip layer 12, respectively, can have a shorter length when it is applied by a cut-and-place application 16 (intermittent application according to FIG. 3).

[0048] It is further noted that said non-intermittent application is especially illustrated by the top view 17 of the product or the absorbent article, respectively, which is shown in FIG. 2, whereas said intermittent application is especially elucidated with the aid of the top view 18 of the product or the absorbent article, respectively, which is shown in FIG. 3. In addition to this, said top views 17, 18 especially illustrate the position for the opening 21.

[0049] Generally, the opening of the backsheet layer 11 is cut with the aid of at least one of a rotary knife, a punching tool, a laser cutting tool, a water jet cutting tool, or any combination thereof. In the case of both FIGS. 2 and FIG. 3, the opening is exemplarily cut with the aid of a cutting die 15. Furthermore, as approximately mentioned above, the cover strip layer 12 may be placed between the backsheet layer 11 and the absorbent core layer 13 in such a manner that the opening of the backsheet layer 11 is at least partly covered by the cover strip layer 12.

[0050] Moreover, as roughly mentioned above, it might be particularly advantageous if the width of the cover strip layer 12 is less than the width of the backsheet layer 11 and/or the width of the absorbent article 13. In addition to this or as an alternative, the width of the cover strip layer 12 may be wider than the opening of the backsheet layer 11. Further additionally or further alternatively, the cover strip layer 12 comprises or is a liquid barrier.

[0051] In the case of both the first embodiment of a production line according to FIG. 2 and the second embodiment according to FIG. 3, the cover strip 12 is sealed to the backsheet 11, after creating the opening in the backsheet 11, by applying a glue pattern on the cover strip 12 or on the backsheet 11 (but preferably on the cover strip 12) through an adhesive application or by means of an ultrasonic welding unit or by a combination thereof.

[0052] The sealing pattern preferably creates a liquid barrier by sealing the edges of the cover strip 12 and especially by sealing the front- and/or backend of the strip 12 so that in between a pocket area is formed. Such a sealing at front and/or back can create benefits, for example, to have a precise control on how deeply an element such as the above-mentioned device can be inserted (downwards), or to ensure that an element such as said device cannot be inserted in the wrong direction (upwards).

[0053] Alternatively, in case of an non-intermittent cover strip 11 or in case of a cover strip 11 that extends well enough beyond the edges of the absorbent core 13 of the product, the sealing at front and back may be left out because they are not needed to create a liquid barrier in that case. It is noted that for a combination of different intermittent glue traces, a triple shim or multi shim glue applicator can be used. Additionally or alternatively, the subsequent arrangement of standard glue applicators can be used for the same purpose.

[0054] With respect to the above-mentioned sealing, FIG. 4 shows four exemplary embodiments of forming the pocket by sealing the cover strip 12 to the backsheet 11. In this context, each of said four embodiments illustrates the position for the opening 21. The top left embodiment comprises a glue pattern 24 at every edge (more specifically, front, back, and two side edges) especially for the intermittent case, whereas the top right embodiment comprises a glue pattern 24 at every edge (more specifically, front, back, and two side edges) especially for the non-intermittent case.

[0055] Furthermore, the bottom left embodiment of FIG. 4 comprises a glue pattern 24 at two edges (more specifically, front and back) and a welding pattern 25, preferably an ultrasonic welding pattern, at the other two edges (more specifically, two side edges) especially for the intermittent case, whereas the bottom right embodiment comprises a welding pattern 25, preferably an ultrasonic welding pattern, at every edge (more specifically, front, back, and two side edges).

[0056] With respect to said four embodiments according to FIG. 4, it is noted that glue and welding patterns can interchangeably be applicated with regard to each other.

[0057] Again, with respect to FIG. 2 and FIG. 3, the backsheet 11 comprises at least one outer layer with a non-woven substrate 11a and at least one inner layer with a non-permeable film 11b. The film can have breathable properties and it might be printed (both optionally). The laminate of at least one inner layer and at least one outer layer can be created with an inline lamination process.

[0058] Alternatively, the lamination process can be managed in advance, so that the pre-laminated backsheet can be used only on the unwinder for the backsheet film. Further alternatively, it is noted that the backsheet may comprise only one layer which is at least a non-permeable film, preferably a liquid-impermeable film.

[0059] As it can further be seen from both FIG. 2 and FIG. 3, the opening of the pocket is created by the above-mentioned cutting die 15 that follows the backsheet lamination process step (if applicable) and that is placed before the lamination step of the cover strip 12. Through the opening the pocket especially becomes accessible from the outer side of the absorbent article 13. The opening is especially placed at the same position for every product or absorbent article, respectively, by speed synchronization of the cutting die 15.

[0060] As an alternative to the creation of a pocket with an opening at any position within the absorbent article, preferably a diaper, a pocket can be created in the same manner through sealing left, right (and bottom) edges of the cover strip, but with its front edge not sealed and aligned with the front edge of the diaper. This avoids the need for an additional knife installation, but it may have the disadvantages that there is no freedom for where to position the pocket (it can only be accessed at the edge of the product) and that it may be difficult to separate the cover strip from the backsheet to access the pocket (as these thin layers typically stick together by static electricity).

[0061] As a further alternative to the creation of a pocket with an opening as imagined above, the entire part of a backsheet above the intended location of the opening may be removed, leaving only the cover strip as a barrier between the absorbent core and the outside of the product or the absorbent article, respectively, which may lead to several disadvantages.

[0062] Again, with respect to the first embodiment of a production line according to FIG. 2 and the second embodiment according to FIG. 3, it is noted that the backsheet may be printed and/or embossed and the design or pattern, respectively, may preferably be registered with a certain repeat length, especially aiming to have the same portion of the print design positioned in the same way for every single product or absorbent article, respectively, in machine direction. In this context, said machine direction is especially defined as the direction of the production process.

[0063] This may preferably require a registration control. In accordance with FIG. 2 and FIG. 3, the print or the printed and/or embossed pattern, respectively, of the backsheet 11 is monitored by a monitoring device, exemplarily an optical sensing unit 14 such as an eyemark sensor or a camera system. The output of that monitoring device is preferably used to control the speed of a pull roller, so that the speed of that driven pull roller can increase or decrease to shift the print design of the printed film to the right position. The right position ensures that also the other recurrent design elements remain relatively to the print design in the same position; this especially applies to the opening, to the sealing pattern of the pocket and to the position of the absorbent core.

[0064] Furthermore, the printed backsheet may also be controlled to stay in the right position in cross-direction. In this context, said cross-direction is especially defined as the direction perpendicular to the machine direction, within the plane of the product or the absorbent article, respectively. A device being configured to control the position of the respective web in cross-direction such as a web guide can control and adjust the position of the substrate according to the edges of the substrate.

[0065] Alternatively, the web guide or said device, respectively, can control and adjust the position of the substrate according to the print on that substrate by using an identification device such as a camera system that identifies the cross-directional position of the print relatively to the general center line. This method is advantageous because a print may sometimes not be exactly centered against the edges of its substrate. The web-guiding element ensures that the print in cross-direction remains in the same position relatively to the arrangement of other elements, such as the sealing pattern of the pocket or the position of the opening to said pocket.

[0066] Moreover, with respect to the above-mentioned printed and/or embossed pattern, FIG. 5 shows said pattern 22 or design, respectively, within the scope of four exemplary cases of alignment or misalignment with respect to the elements of the product or the absorbent article, respectively. In this context, each of said four embodiments illustrates the position for the opening 21 and the general center line 23.

[0067] As it can be seen from FIG. 5, according to the top left embodiment, all elements of the product are at correct position, whereas in accordance with the top right embodiment, the printed and/or embossed pattern 22 is not centered on the substrate. Furthermore, according to the bottom left embodiment, the substrate is shifted from the center line 23, whereas the printed and/or embossed pattern 22 is shifted against the target position in machine direction in accordance with the bottom right embodiment of FIG. 5.

[0068] Now, with respect to FIG. 6, an exemplary embodiment of an absorbent article, especially in the form of a diaper, in accordance with the invention is illustrated.

[0069] Exemplarily, according to FIG. 6, the inventive pattern comprises a non-conductive pattern 22 and a conductive pattern 26. For instance, with the aid of the non-conductive pattern 22, the respective product type and/or the size of the product may be shown.

[0070] Finally, FIG. 7 presents a flow chart of an exemplary embodiment of the inventive manufacturing method in greater detail.

[0071] As it can be seen from FIG. 7, the method comprises the step of a lamination of backsheet layers 200.

[0072] Before said lamination step 200, a backsheet inner layer with the inventive pattern, exemplarily a segmented pattern, is provided according to step 206. In this context, it is noted that there may exist an optional inline process for applying said pattern or segmented pattern, respectively, on the backsheet layer or the backsheet inner layer, respectively, in accordance with the optional step 205.

[0073] Further optionally, before the lamination step 200, a backsheet outer layer may be provided according to step 207.

[0074] After said lamination step 200, the speed for the backsheet layer is controlled according to step 201 especially with the aid of the inventive first offset value (x). Furthermore, in accordance with step 202, the cross direction for the backsheet is controlled especially with the aid of the inventive second offset value (y).

[0075] Moreover, in accordance with step 203, a cutting die is exemplarily used to make or cut the opening. It is further noted that according to step 204, a vision control system may be used for an inspection of the backsheet layer with the inventive pattern, exemplarily the segmented pattern, and the inventive opening.

[0076] Said vision control system may especially provide the input for correction, exemplarily the first offset value x, for the above-mentioned step 201 and/or the input for correction, exemplarily the second offset value y, for the abov-mentioned step 202.

[0077] Furthermore, according to step 208, a cover strip layer is provided. With respect to said cover strip layer, a cut and place processing may optionally be performed for an intermittent application of the cover strip layer in accordance with the optional step 209.

[0078] Moreover, before an absorbent core is provided according to step 211, a lamination of the cover strip layer and the backsheet layer is performed in accordance with step 210.

[0079] While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. Numerous changes to the disclosed embodiments can be made in accordance with the disclosure herein without departing from the spirit or scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above described embodiments. Rather, the scope of the invention should be defined in accordance with the following claims and their equivalents.

[0080] Although the invention has been illustrated and described with respect to one or more implementations, equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In addition, while a particular feature of the invention may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application.