Abstract
The present invention relates to rolls of an elongated material and to methods of manufacturing fastening tabs.
Claims
1. A roll of an elongated material, the elongated material comprising first and second major surfaces, two longitudinal edge portions and a central portion provided in the width direction in between the two longitudinal edge portions, the width of each longitudinal edge portion being at most 30% of the total width of the elongated material, wherein each of the two longitudinal edge portions has mechanical fastening elements provided on at least a region of the first major surface along the length of the elongated material, wherein the fastening elements on each edge portion comprise male fastening elements, wherein the central portion comprises an innermost central region, the first major surface of the innermost central region being free of fastening elements, and wherein the second major surface is free of adhesive, and wherein the fastening elements are provided on the roll of elongated material, from which individual tabs can be cut and wherein the roll is a twin roll comprising, along the cross direction, two adjacent fastening tabs and wherein the width of each longitudinal edge portion is at least 13% of the total width of the elongated material.
2. The roll of claim 1, wherein the first major surface of the innermost central region of the central portion is free of adhesive.
3. The roll of claim 1, wherein the width of the innermost central region ranges from about 7% to about 30% (inclusive) of the total width of the elongated material.
4. The roll of claim 1, wherein each of the longitudinal edge portions comprises an outermost edge region whose first major surface is free of fastening elements.
5. The roll of claim 4, wherein the width of each of the outermost edge regions is in the range between 3% and 10% (inclusive) of the total width of the elongated material and wherein the width of each of the outermost edge regions is in the range between 3 mm and 12 mm (inclusive).
6. The roll of claim 1, wherein each of the longitudinal edge portions comprises a fastening region, the fastening elements being provided on the first major surface of each of said fastening regions.
7. The roll of claim 6, wherein the width of each of the fastening regions is in the range between 10% to 27% (inclusive) of the total width of the elongated material and wherein the width of each of the fastening regions is in the range between 10 mm and 30 mm (inclusive).
8. The roll of claim 1, wherein the elongated material is a laminate comprising a carrier web extending over substantially the total width of the elongated material and a fastening material comprising a plurality of fastening elements, wherein each longitudinal edge portion is provided with at least one elongate strip of the fastening material.
9. The roll of claim 8, wherein the at least one elongate strip of the fastening material in each longitudinal edge portion is directly or indirectly affixed to the carrier web via adhesive, ultrasonic welding, or hot air welding or via in-situ lamination.
10. The roll of claim 1, wherein the roll is a planetary roll or a cross wound roll.
Description
[0024] Further preferred features are illustrated with reference to preferred embodiments which are shown in the following Figures, which show:
[0025] FIG. 1 a schematic cross-section of an exemplary embodiment of an elongated material wound in an exemplary roll in accordance to the present invention, said exemplary roll shown in FIGS. 2 and 3;
[0026] FIG. 2 a schematic, partial cross-section of an exemplary embodiment of a roll of an elongated material according to the present invention;
[0027] FIG. 3 a schematic, perspective view of an exemplary embodiment of a roll of an elongated material according to the present invention;
[0028] FIG. 4 a schematic, partial cross-section of another exemplary embodiment of a roll of an elongated material according to the present invention;
[0029] FIG. 5 a schematic perspective view depicting an exemplary embodiment of a method of manufacturing fastening tabs according to the present invention;
[0030] FIG. 6 a schematic cross-section of a fastening tab manufactured according to the present invention attached to a diaper web; and
[0031] FIG. 7 a schematic cross-section of a further exemplary embodiment of an elongated material to be provided in a roll according to the present invention.
[0032] FIG. 3 shows a schematic perspective view of an exemplary embodiment of a roll 1 of an elongated material 2 according to the present invention while FIG. 1 shows a schematic cross-section of a single layer of the elongated material and FIG. 2 shows a schematic, partial cross-section through a number of layers of the elongated material arranged on the roll. As can be appreciated from FIG. 3, the exemplary roll is a planetary roll.
[0033] Referring to FIG. 1, the elongated material 2 includes a carrier web 2a extending over substantially the total width of the elongated material and comprises a first major surface 3 and a second major surface 4, two longitudinal edge portions 5a and 5b and a central portion 6 provided in the width direction in between the longitudinal edge portions 5a and 5b. Each of the two longitudinal edge portions 5a and 5b has mechanical fastening elements 8 provided on at least a region of the first major surface 3. The width of each longitudinal edge portion 5a, 5b is at most 30% of the total width of the elongated material 2. As also shown in the exemplary embodiment, favorably each of the longitudinal edge portions 5a and 5b comprises an outermost edge region 7a and 7b, respectively, whose first major surface 3 is free of fastening elements. These outermost edge regions 7a and 7b may be used as a finger lift in the final fastening tab. In the exemplary embodiment, the remaining regions of the longitudinal edge portions 5a and 5b form fastening regions 8a and 8b, respectively, each comprising fastening elements 8. As shown in the exemplary embodiment, said fastening regions 8a and 8b may be provided with elongate strips of a fastening material 28 along the length of the elongated material, said strips comprising a plurality of fastening elements 8 as can be recognized in FIG. 3. In particular, it can be recognized from FIG. 3 the elongated material includes two elongate strips of fastening material extending along the longitudinal direction of the elongated material. In the exemplary embodiment shown in FIGS. 1 to 3, the strips of fastening material 28 are attached to the carrier web 2a via adhesive 9.
[0034] Elongate strips of the fastening material may be directly or indirectly attached via adhesive, ultrasonic welding, and/or hot air welding. In addition it will be appreciated that fastening elements may also be provided in different patterns. For example each of the fastening regions may be provided with two or more (e.g. four) separate elongate strips of fastening material, each running along the length of the elongated material so that the resulting tabs include two or more patches of fastening elements with areas free of fastening elements in between the patches. Alternatively each of the fastening regions may be provided with at least one elongate strip of fastening material that is provided in the form of a reticulated mechanical fastener comprising multiple strands of fastening materials attached and/or integral to each other at bridging regions of fastening material. Examples of such a reticulated mechanical fastener are described in detail in WO 2012/112768 A1. Specific reference is made to this document, which is incorporated by reference herein in its entirety, in particular with regard to the structure of such reticulated mechanical fasteners and the manufacturing thereof.
[0035] This is best understood by reference to FIG. 7 showing a schematic cross-section of another exemplary embodiment of an elongated material to be provided in a roll according to the present invention. The exemplary embodiment shown in FIG. 7 includes an elongated material 2 comprising a first major surface 3 and a second major surface 4, two longitudinal edge portions 5a and 5b and a central portion 6 provided in the width direction in between the longitudinal edge portions 5a and 5b and including a innermost central region 6a. Each of the two longitudinal edge portions 5a and 5b includes fastening regions 8a and 8b comprising either multiple elongate strips of fastening material with mechanical fastening elements 8 or one elongate strip of fastening material that is provided in the form of a reticulated mechanical fastener comprising multiple strands of fastening materials attached and/or integral to each other at bridging regions of fastening material. In this embodiment, the elongate strips of fastening material 28 are attached directly to the carrier web 2a via e.g. ultrasonic welding and/or hot air welding.
[0036] The fastening elements may comprise male fastening elements which are, e.g., selected from the group consisting of hook fasteners, mushroom-shaped fasteners, stem-shaped fasteners, cup-shaped fasteners, T-shaped fasteners and mixtures thereof.
[0037] Carrier webs may be single-layered or multi-layered. They may comprise a film, a nonwoven, a textile (e.g. woven or knitted), a foamed material or combinations thereof, e.g. in the form a laminate (such as multilayer film laminate, multilayer nonwoven laminate or a film-nonwoven laminate). The layer(s) of carrier webs may made of various substances such as, for example, polypropylene, polyvinylchloride, polyethylene terephthalate, polyethylene, polyolefin copolymers or blends of polyolefins such as, for example, a blend of polypropylene, low density polyethylene and/or linear low density polyethylene. Carrier webs are desirably between 30 microns and 500 microns in thickness, and more desirably between 40 and 150 microns.
[0038] Returning to FIGS. 1 to 3, it can be seen that in the exemplary embodiment depicted in FIGS. 1 to 3, the first major surface 3 of the entire central portion 6 is free of fastening elements. As mentioned above, at least the innermost central region of the central portion is free of fastening elements so that such portion or at least a part of such portion thereof can be used to affix tab(s) obtained from such roll to absorbent article(s) or precursor materials. This can be readily appreciated from FIG. 5 which shows a schematic perspective view depicting an exemplary embodiment of a method of manufacturing fastening tabs where adhesive is applied onto the innermost central region 6a of the central portion 6. The method will be discussed in more detail below. In the exemplary embodiment shown in FIGS. 1 to 3, it can be seen that the first major surface 3 across the entire width of the central portion 6 is also free of adhesive.
[0039] As mentioned above in favorable embodiments, the innermost central region is free of adhesive. In addition while it may be desirable that the first major surface of the entire central portion is free of fastening elements, the first major surface of the central portion in regions outside the innermost central region, in particular just adjacent to the two longitudinal edge portions, may include adhesive for example to provide for fastening tabs including a so-called “anti-flagging feature”. This is best understood by reference to the exemplary embodiment shown in FIG. 7. In particular in exemplary elongated material shown in FIG. 7 the first major surface 3 across the entire central portion 6 is free of fastening elements. In addition, while the first major surface 3 across the innermost central region 6a is free of adhesive, it can be seen that the first major surface of the central portion in two side regions outside the innermost central region, in particular just adjacent to the two longitudinal edge portions, may be provided with an adhesive 29 to provide for an “anti-flagging feature” in the resulting fastening tabs.
[0040] Returning to the exemplary embodiment shown in FIGS. 1 to 3, in particular to the illustration of FIG. 2, the elongated material 2 is wound up on a roll 1, in the form of a planetary roll, e.g. comprising a roll core 1a. Since the thickness of the elongated material 2 is largest in the fastening regions 8a and 8b, which comprise the fastening elements 8, contact between adjacent layers of the elongated material 2 being wound up on a roll 1 is, in essence, provided in these fastening regions 8a and 8b. Since these fastening regions 8a and 8b are provided at or close to the side edges of the elongated material 2 and thus the roll 1, the roll reveals enhanced stability, in particular during unwinding and handling. Furthermore, penetration of dust and dirt particles is effectively prohibited and/or reduced due to the presence of at the fastening regions 8a and 8b at or close to the edges of the roll.
[0041] As mentioned above, the roll may also favorably be provided in the form of a cross wound roll. FIG. 4 shows a schematic, partial cross-section of such a roll. The elongated material 2 of the embodiment shown in FIG. 4 is the same as that shown in FIGS. 1 to 3. As can be appreciated from a comparison of FIG. 2 and FIG. 4, instead of winding the elongated material directly on top of itself, the elongated material is wound helically back and forth across the width of the roll, in particular onto a roll core 1a. It will be appreciated from FIG. 4, the positioning of the fastening regions 8a and 8b at or close to the side edges of the elongated material 2 desirably allows for a transverse offset in the next winding of elongated material (and thus crossing winding of the elongated material), since at least one of fastening regions of the next winding can be positioned between those of the previous winding. It will also be appreciated from a comparison of FIGS. 2 and 4 that the cross wound roll is wider than the planetary roll, which further facilitates roll stability. In addition as mentioned above, for a given roll diameter, the provision of a cross wound roll allows for longer roll lengths relative to a planetary roll.
[0042] FIG. 5 schematically shows an exemplary embodiment of a method of manufacturing fastening tabs and of fixing said fastening tabs at their manufacturer's end to an absorbent article or to an absorbent article precursor material. In particular, FIG. 5 depicts the manufacture of fastening tabs and the affixing of the generated fastening tabs to an absorbent article precursor material 11, which may be a diaper or incontinence brief precursor web. As can be seen, a roll 1 of an elongated material 2, such as the roll shown in FIG. 3, is provided. The elongated material 2 is unwound from the roll 1 and an adhesive 19 is applied onto the first major surface 3 of the innermost central region 6a of the central portion 6 by an adhesive applicator head 10. The elongated material 2 is then slit along its length through the innermost central region 6a by means of a cutting tool 15 which also slits through the adhesive 19 provided on the first major surface 3 of the innermost central region. Thus, the elongated material 2 is divided into two endless sheets or strips of tab material, which are essentially mirror images of one another. Each of the two elongated strips of tab material comprises one of the two longitudinal edge portions 5a and 5b and a section of the central portion 6. Each of the two elongated strips are then cut in the cross direction in order to provide fastening tabs 14, each having a user's end and a manufacturer's end. In the exemplary embodiment shown in FIG. 5, each of the two elongated strips of fastening tab material is fixed to a vacuum wheel 12 and cut by a cutting wheel 13 into individual fastening tabs 14 while being kept in place on the vacuum wheel 12. The individually cut fastening tabs 14 are kept in place by the vacuum wheel 12 until they are applied to the diaper or incontinence brief precursor web 11. As shown in FIG. 5, as the web 11 moves forward (from left to right in the Figure) the fastening tabs 14 are affixed pair-wise at an appropriate interval to the web 11 using the adhesive 19 applied previously onto the first major surface 3 of the innermost central region of the central portion 6. As is evident from FIG. 5, the provision of the user's ends of the fastening tabs to be cut from the elongated material in the outer edge portions of the elongated material also allows for an easier application of the cut fastening tabs to a web, because the cut fastening tabs may be applied directly to the web in their orientation as cut without having to be flipped or rotated by 180°. FIG. 6 shows a schematic cross-section through the diaper or incontinence brief precursor web 11 with the fastening tabs 14 being affixed to the web via the adhesive 19 in the manufacturer's ends 14b with the user's ends 14a extending outwardly away from the web. As can be appreciated from FIG. 6, since the adhesive 19 is provided to the very edge of the tab in the manufacturer's end 14b, the edge of the tab is cleanly adhered to the web with no remaining flap of non-adherent tab material.
[0043] It is to be mentioned that although not as favorable as the exemplary method shown in FIG. 5, one could alternatively apply adhesive after the slitting step and prior to cutting step, i.e. apply adhesive at or close to each of the innermost edge regions of the two elongated strips of fastening tab material generated upon slitting.
[0044] It will be appreciated that the fastening tabs may be attached to absorbent articles per se or to alternative absorbent article precursor materials. In regard to the latter, for example, fastening tabs 14 may be instead, affixed to an ear web, said ear web may, in turn, be affixed to a diaper or incontinence brief precursor web.
[0045] The fastening tabs may also be affixed to the absorbent articles or absorbent article precursor materials by other techniques such as ultrasound welding, hot-air welding or the like. In such cases, one would dispense with the step of applying adhesive onto the first major surface of the elongated material e.g. as shown in FIG. 5.
