FIELD OF THE INVENTION
The present invention is an article such as a garment to be worn on the lower torso of a wearer, such as pants or diapers. The article exhibits snug fit around the legs of a wearer through a particular cooperative arrangement of side panels and a centre strip. The present invention is further a manufacturing method for producing such articles.
Because of the quite complex shape of human bodies, the automated manufacturing of garments is typically a compromise of manufacturing speed versus complexity of the shape of the garment or article.
On one side, very slow machines, which may include sewing and /or even manual intervention for certain steps, can produce quite complex garments such as well fitting pants or underwear, such as described in U.S. Pat. No. 7,155,940 in the context sewing three knitted half-blanks into a panty garment.
The other extreme are for example high speed machines producing disposable articles, such as baby or adult incontinence diapers, training pants and the like at production speeds of several hundred articles per minute or even more. Such articles, however, are much less complex in their design with regard to shape, and whilst the body fit is often somewhat improved by elastic materials, the manufacturing costs are significantly increased. Typically, such articles are manufactured from two-dimensional webs, such as nonwoven or films, by merely overlaying, connecting, and folding. In the early development of disposable diapers, such articles have been manufactured by folding the longitudinal outer side portions of an essentially rectangular web or pad over the mid portion, either as a simple overfold, such as e.g. described in U.S. Pat. No. 3,572,342, or as a double pleat (Z-fold) such as described in U.S. Pat. No. 3,426,756. In the crotch region, the fold was secured by a so called “centre glue”, such that upon use the pad was unfolded in the front and/or rear waist region, but it retained a narrow configuration in the crotch region, thereby approximating an hourglass shape. Further developments introduced the “shaped diapers” by introducing leg cut outs, elastic elements, waist ears etc., etc. Out of the plethora of publications in this area, WO08/118713, WO98/14156, EP0901780A1 may serve as examples showing such contemporary conventional articles.
Recently, “body conforming articles” as well as manufacturing methods for such articles have been described such as in WO06/102974.
Whilst these articles show an improved body fit, particularly in the leg and crotch area, there is still a need for increasing the flexibility in the design and in particular in the material selection and arrangement in the article.
There is also a need for alternative production methods, in particular with regard to adapting existing manufacturing equipment. There is also a need for increased output per converting line.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows an article in the form of a pants style absorbent article.
FIG. 2A to C show schematically an article according to the present invention.
FIG. 3 shows schematically a particular embodiment of the present invention.
FIG. 4 shows schematically a further particular feature of the present invention with regard to connecting regions.
FIG. 5 shows schematically an article comprising unitary side panel and centre as a further particular execution according to the present invention.
FIG. 6 shows schematically an article comprising legs hoops as yet a further particular execution of the present invention.
FIG. 7 shows schematically an article wherein the side panel is folded and glued so as to provide the functionality of a leg hoop.
FIG. 8 shows schematically further embodiments according to the present invention.
FIG. 9A to E show various executions according to the present invention relating to the double pleats.
FIG. 10 shows schematically an article according to the present invention in a pre-use configuration.
FIG. 11A to G show schematically the process steps for forming articles comprising leg hoops in an MD-manufacturing process.
FIG. 12A to D show schematically the process aspects for forming closed articles.
FIG. 13A and B show schematically a setup of a CD- and MD- multi-lane converter,
The same numerals across different figures denote identical features
The present invention relates to articles, typically worn by humans, although not necessarily limited thereto. Within the context of the present invention, the term “article” shall also comprise “pre-cursor of an article”, such as when an unfinished precursor, which is made according to the process described herein is finished such as by adding further elements or features. The articles according to the present invention are preferably shaped so as to adapt well to body contours in particular around the lower torso and around the legs in the upper thigh respectively crotch region. Within the present context, the leg region of a standing wearer extends from the crotch line downwards, whereby the crotch line is defined by the crotch crease or groin adjacent to the pubic area and an essentially horizontal circumferential line through the groin laterally outwardly around the leg.
The articles according to the present invention comprise a front and a rear region, typically corresponding to the waist regions of a wearer, and a crotch region there between, thereby defining the longitudinal orientation if the article. The article further comprises side panel regions, which extend laterally outwardly of the centre piece when the article is in its in-use configuration. In a pre-use configuration, i.e. during manufacturing, or in a folded article after manufacturing, the side panels may be folded so as to or otherwise overlay the centre piece. Between the crotch region and the waist regions, the article comprises hip regions, whereby all these regions correspond to the regions of a wearer during its intended use. The articles may further comprise a left and right leg hoop, which during use encircle the upper thigh of a wearer. The article according to the present invention is essentially symmetrical to its longitudinal centreline. Nonetheless the description may refer to one major part of the article only, say the part which corresponds to the left back body parts of a wearer, but yet the features may be applied to the three other major parts of the article.
Thus, an article according to the present invention comprises a front region, a rear region and a crotch region there between, thereby defining a longitudinal (x-) and width (y-) direction and a longitudinally extending centre line of the article. A centre strip extends from the front region through the crotch region to the rear region, exhibiting a first and a second longitudinally extending side margin and a first and a second surface. The articles comprise at least a first and a second rear, optionally a first and a second front side panel connected to the centre piece in connecting regions, respectively wherein each of the side panels exhibit a first and second longitudinally extending side margin and a first and a second surface. The centre piece connecting regions extend essentially along the side margins of the centre piece in the rear region and optionally front region of the centre piece and the side panel connecting regions extend essentially along the first side margins of the side panels,
At least in the pre-use configuration, the centre piece and the side panels may be positioned such that their second surfaces are oriented towards each other and the first side margin of the first rear side panel is connected to the first side margin of the centre piece and the first) side margin of the second rear side panel is connected to the second side margin of the centre piece. Optionally the first side margin of the first front side panel is connected to the first side margin of the centre piece and the first side margin of the second front side panel is connected to the second side margin of the centre piece. Through this arrangement, the second side margins of the first and second rear and optionally front side panels extend towards and optionally beyond the longitudinally extending centre line of the centre piece, but not to the connecting region of the respective opposite side panel.
FIG. 10 shows an article respectively a pre-cursor there for according to the present invention in a pre-use configuration, having a centre piece 1010 with side panels 1055 connected thereto. Although a first (2318) and a second (2328) rear as well as a first (2312) and a second (2322) front side panel are shown, the latter ones are not necessary for the invention to function. The centre piece has a second surface, here shown as article's outer surface 1021 oriented towards the viewer and first opposite surface (1022), which will be oriented towards the user in the in-use configuration (e.g. a topsheet surface). The side panels are shown as individual web pieces connected to the centre piece in the connection regions 1123, here shown as straight lines, which may be glue lines or regions, or which may be ultrasonic or heat pressure bonding lines or regions. These connection regions extend essentially along a first (1011) and an opposite second (1017) longitudinally extending side margin of the centre piece 1010 at least in the rear region and—as shown in FIG. 10—also in the front regions and the corresponding connecting regions of the side panels along a first longitudinally extending side margin of the side panels. The sidepanels overlay the centre piece with the second of their surfaces oriented towards the centre piece such that the facing surfaces of the centre piece and the side panel are corresponding surfaces during use, i.e. as shown in FIG. 10, the outer surface 1021 of the centre piece is oriented towards the viewer whilst the surface of the side panels oriented towards the viewer will be the inner surface oriented towards the user during use. Considering the first rear side panel 2318, the second longitudinally extending side margin 4070 is positioned away from the first longitudinally extending side margin 1011 of the centre piece towards the longitudinally extending centre line 1005 or beyond, but not into, the connecting region of the second rear side panel.
Optionally, the side panels may be folded or even be multiply folded, such as in an “accordion” or “leporello” type of fold. Optionally, the sidepanels are composed of more than 1 web, connected to each other along connecting regions by butt or overlapping connections.
Such a pre-cursor can be readily converted into a finished article, such as by adding further features, such as closure tapes or by connecting the first front and rear and second front and rear side panels so as to form a pants style article, or it may already present an article except for not being in its “ready to use” or “in use” configuration.
The article may be further converted by overfolding longitudinal sections of the centre piece towards the centre line of the article such that the first (or wearer oriented) surfaces are oriented towards each other. In the crotch region, this overfold may be stabilized by connecting the surfaces to each other, such as by conventional glue bonding
In a particular embodiment, the article can be adapted to fit particularly well to the body contours during use, which may be achieved by a particular folding of the side margins of a centre strip and laterally outwardly extending side panel regions in a double pleated or Z-fold configuration. In the making of the article at least one of the pleats has been affixed such as by connection lines or regions e.g. by adhesive or heat bonding. There are a number of options for the arrangement of the double pleats, used materials, and the affixing, as further explained with FIG. 9A to E. Therein is exemplarily shown the embodiment of an absorbent article such as a taped diaper and one of the rear parts is depicted in a schematic cross-sectional view. As shown in FIG. 9A(1), the core 1035 is enveloped between a topsheet 1025 and a backsheet 1045, together forming the centre strip. As shown, topsheet and backsheet run as a composite into the double pleat 1190 towards the first pleat tip 1193, where they terminate. A separate side panel material 1055 has been overfolded, and the non-folded part runs laterally outwardly towards a closure element, e.g. a closure tape 1150. The longitudinal fold of the side panel forms the second pleat tip 1195, from where it further runs towards the first pleat tip where it terminates. In this first pleat 1192, the side panel is affixed to the topsheet/backsheet laminate in a butt-type attachment, such as by the first attachment 1120 (as solid line). An optional contour attachment 1123 (as dotted line), as will be described further, may be placed in the first pleat. This contour attachment may be integral with or even identical with the first attachment. The embodiment as shown in FIG. 9A(2) differs in that the optional contouring attachment is in the second pleat. FIG. 9A (3) and (4) show equivalent embodiments, except that the pleating is done in the opposite direction.
In another execution, at least one material of the centre piece may extend continuously across the centre piece and the side panel regions, such as the topsheet, or backsheet, or the topsheet/backsheet composite. Thus, as shown in FIG. 9A (5) to (8), and in analogy to FIG. 9A(1) to (4), the double pleating may be executed forward or backwardly, and the first attachment shown as solid line 1120 is positioned in the first or second pleat. The contouring attachment shown as dotted line 1123 fixation may be placed in either or both of the pleats. The contouring attachment may also be integral or identical with the first attachment 1120, as indicated with the further options depicted in FIG. 9C.
Optionally, the (front and/or rear) sidepanels may be composed of more than one web which partly overlay each other and are attached to each other as described above, and—non-limiting—depicted in FIG. 9D and E.
Optionally and further enhancing the adapting to the body contours, the contouring attachment can be executed such as by shaped or contoured attachment, such as adhesive or heat bonded lines or regions. Upon donning and wearing the article, this creates an effect very similar to the one of darting or tucking in tailoring. This shaped attachment can be achieved such as by a curved attachment line, or by predetermined irregularly shaped attachment regions. Thus, when considering an article in its in-use configuration—i.e. when the centre piece to side panel connection is cross-directionally pulled out—the distance between the longitudinal centreline and the innermost demarcation line of the innermost of the contour attachment lines or regions is different in the hip regions from the corresponding distance in at least one of the waist or hoop regions. In the present context, the term “innermost” refers to the position relative to the longitudinal centre line of the article.
Optionally, the present invention can very suitably be used for designing articles, such as disposable absorbent articles, comprising a so called secondary topsheet for separating faeces from the skin of the wearer.
In yet a further option, the present invention allows designing of pants or pants-style structures comprising well fitting leg hoops.
The present invention relates to articles which may be closed pants or pants-style articles or to articles, which are open products, and which may be brought into a closed pants-style form upon donning The present invention further relates to pre-forms of such articles, which may require addition of certain elements or performance of certain process steps to be functional as an article.
The general features of a pants-style article are depicted in FIG. 1, showing exemplarily for closed pants, such as an absorbent article, such as so called training pants, an article 1000 having a front waist region 1012 and a rear waist region 1018 connected by a crotch region 1015, thereby defining a longitudinal (x-) direction 1001 of the article. A width (y-) direction 1002 of the article corresponds to the right-left orientation on a wearer. Typically, the thickness (z-direction) of the articles is much smaller than the length and width, and extends perpendicularly thereto.
The articles according to the invention exhibit a wearer oriented, or inner surface 1020, in the context of disposable articles such as diapers also referred to as the topsheet side, and an opposite or outer surface 1021, in the context of disposable article also often referred to as backsheet side.
Such pants-style articles may be closed by side closure means, here shown as a butt-type side seam 1105 with connecting points 1107. In this butt-type seam the inner surfaces of the front and back regions are contacting each other and bonded to each other, such that outer margins of the webs form the distal end of the seam and extend outwardly away from the wearer during use.
Within the present context, the orientations relative to the article during its use are also applied to an article prior to the wearing. For most articles, the determination of longitudinal respective cross-directional orientation and of inner and outer surfaces can be straightforwardly deduced from the intended use by a skilled person. For certain articles, such as articles constructed of essentially one sheet of material, or designed symmetrically in the front and back, the orientation may be defined so as to provide the best comfort for the wearer, such as determined by outwardly lying butt seams.
Articles according to the present invention may have absorbent elements, as is the case for disposable absorbent articles such as baby or adult incontinence diapers, or for training pants and the like. Such articles may also be designed without integral absorbent elements, but may be combined with separate absorbent elements, such as when pants are used in combination with absorbent pads for the use in the context of adult incontinence or for feminine hygiene. Such articles may also be designed with no or relatively little absorbency, and may be used as disposable, or limited re-use underwear. Articles having no or only little absorbent capacity may be designed to withstand at least a limited amount of wash cycles without disintegrating.
In the case of pants or pants style structures these may be manufactured as completely closed pants—either permanently or releasably—or in an opened configuration, such as conventional baby or adult incontinence diapers. Such articles are closed to form a pants-style structure by the user or a caretaker upon donning of the article.
Pants-style articles according to the present invention comprise a centre strip and side panels. Both the centre strip and the side panels have major inner surfaces (i.e. predominantly oriented towards the wearer during use) and major opposite surfaces generally oriented away from the wearer. Within the present description, the term “major” surface refers to the orientation of a surface of a material or an article, which does not exclude, that certain portions of the material or surface are oriented differently, such as when a part of the material is folded away. No more than 50% of the material, typically less than about 25% and often less than about 10% of the total material should exhibit an orientation different from the major surface.
It is a particular design element of pants-style articles according to the present invention that due to the double pleating the side panels may be connected to the centre strip with their opposite surface oriented towards the opposite surface of the centre strip, e.g. backsheet side to backsheet side. This has particular advantages during the use of the article, as upon closing of the sides of the article either during manufacturing or by the user the lower section of the side panels cooperates with the crotch region of the centre strip to allow snug fit around the legs of the wearer.
An exemplary design according to one embodiment of the present invention is shown in FIG. 2, showing a precursor of an article during a manufacturing step. It is symmetrical along its longitudinal centreline 1005. FIG. 2A exhibits a top view of the inner surface 1020 of a precursor 1000 according to the present invention (i.e. the general orientation towards a wearer). The precursor is shown during its manufacturing as a segment of a continuous web still connected at the segment demarcation lines 1009 to a leading segment 1000′ and trailing segment 1000″. The segment may correspond to a finished article just prior to its final cutting step. As shown, the article may be an open type diaper—here shown with upper (waist) closure tapes 1157 and lower (leg) closure tapes 1152 and with corresponding tapes 1157′ and 1152′ for a leading segment.
Along the longitudinal centreline 1005 of the article 1000, the precursor has a front 1012, rear 1018 region and a crotch region 1015 positioned there between. As also can be seen in the cross-sectional views in FIG. 2B, the precursor has a centre strip 1010, here shown as a composite of a topsheet 1025, a backsheet 1045 and a core 1035 enveloped there between. The elements of the centre strip may be suitably connected to each other, such as by gluing, as well known in the art.
The precursor as shown has four side panels 1055 connected to the centre strip extending in the front and back laterally outwardly of the centre strip, here shown longitudinally coextensive with the centre strip, thusly forming front 1013 and rear 1019 margin of the article, as shown in the figure coinciding with the segment demarcation line 1009. The precursor further comprises side panel hoop regions 1174 extending in the side panel regions from the cross-directionally extending crotch margin away from this margin and centre piece hoop regions 1172 essentially connecting these along the longitudinally extending side margins in the crotch region. Further, the precursor comprises hip regions 1178 essentially positioned between the hoop regions and the waist regions.
As can be seen in the cross-sectional views AA and BB, the centre strip is folded along longitudinal foldlines 1007. The width of this folded-over portion determines the size of the overlap area in which centre strip and side panels can be connected. As such it also influences the contour adapting effect of the side panel to centre strip connection, as being discussed in more detail herein below. For a baby size product, the overlap may be between 3 and 50 mm, for an adult size product it may be between 3 and 100 mm
The side panels are connected to the centre strip via connecting regions, here shown by side panel attachment lines 1120 (shown as a dotted line in the top-view, as they are not visible therein, and as xx in the cross-sectional view). The connecting regions as indicated in FIG. 4 extend preferably between 0 and 10 cm inwardly of the longitudinally extending side margins. Preferably the inwardly oriented (i.e. towards the longitudinal centre line) perimeter of the connection region has a varying distance to the longitudinally extending side margins and/ or centre line.
The centre piece and the side panels are connected so as to form a double pleated (or Z-) fold. In the cross-sectional view (BB)*, which otherwise shows the same features as (BB), this is indicated for one side of the article by the thick dashed line 1190, with a first pleat 1192 and a second pleat 1194 with the respective first pleat tip 1193 and second pleat tip 1995. Attachment glue is positioned in the first pleat 1192. This embodiment shows the second pleat tip 1195 as a fold line of the centre piece material, whilst the first pleat tip 1193 is formed by a butt-type attachment of two materials (i.e. centre piece and side panel), looking as if the pleat tip of a continuous material would be clipped off.
In this design, the side panels 1055 are oriented such that they exhibit a first major surface 1052 oriented towards the wearer and in the top view FIG. 2A shown facing upwardly. Similarly, the centre strip has the major wearer oriented surface of the topsheet 1022 facing upwardly in the cross-directional mid portion of the centre strip, whilst this surface is partly covered by the longitudinally folded side portions of the centre strip, where the opposite surface of the backsheet 1047 (hatched in the top view) faces upwardly. Further variants of this design are shown in e.g. FIG. 8 and FIG. 9A(9) and (10). Therein, a wider topsheet 1025 is folded around the longitudinal side edges of the centre strip, and the folded over regions are attached to the backsheet 1045 by means of a bond line or area essentially parallel to the longitudinal centreline of the article, the folded over parts of topsheet 1025 would be considered part of the backsheet. In a further embodiment, wherein a wider topsheet 1025 is folded around the longitudinal side edges of the centre strip, the folded over regions are attached to the backsheet 1045 by means of a shaped bond area 1125 as depicted in FIG. 4, and to the side panel by means of an essentially straight bond line or area, the folded over part of the topsheet is considered to be part of the side panel.
Thus, the connecting of the side panels to the centre strip is performed by attaching the majorly outwardly oriented surface of the side panel to the majorly outwardly oriented surface of the backsheet. It should be noted, that these connected portions belong to the majorly outwardly oriented surfaces, even though these may have a differing orientation during or after the connecting. Thus, the side panel and the centre strip are connected to each other in a butt-type seam 1110 (in FIG. 2C). This is a particular advantage, as it allows a broader selection and/or easier bonding means or tools for the side panel and backsheet materials, respectively.
This has to be seen in contrast to “conventional” designs as well as to the “body conforming article designs”, wherein the inwardly oriented surface of the side panel is connected to the outwardly oriented surface of the backsheet, or the outwardly oriented surface of the topsheet. If the side panel in conventional products is placed between top- and backsheet, its outwardly facing side is connected to the inwardly facing side of the backsheet, and its inwardly facing side is connected to the outwardly facing side of the topsheet. In contrast to the early pleated “centre glue” designs with an attachment glue in the crotch region, the present invention achieves different effects by affixing the pleats between centre piece and (unitary or separate) side panels outside of the crotch region. Thus, at the latest upon donning of an article according to the present invention, the waist panels are positioned so as to encircle the waist of a wearer, and is further affixed with closure means, such as tapes, here shown as an upper tape system 1152 which may close the article around the waist, and a lower tape system 1157 for closing the article around the legs.
When pulling the article tight in the front and rear waist regions, such as upon donning, the double pleat fold of the centre strip and/or side panel will partly unfold, according to the contour attachment pattern between centre strip and side panel, thus allowing to use the desired width of the combined centre strip and side panels for encircling hips and waist.
In a particular embodiment, the side panels reach well into the crotch region of the article, i.e. below the crotch line on a standing wearer, such that the gap between the crotch portions 1056 of the side panel is relatively small. The optimal dimension of this gap depends on the overall size of the article, and in case of an article fitting babies, such as a baby diaper, in which an overall waist circumference may range from about 350 mm to 700 mm, or be about 450 mm, the gap may be from about 70 mm to about 180 mm, or even between about 100 mm and 140 mm. In case of an article fitting adults where the waist circumference may range from about 700 mm to about 2100 mm, or be in the range of about 1000 mm, the gap may be less than about 290 mm, such as in a range of about 200 mm to about 260 mm. Such a “long” side panel provides a particularly advantageous interaction with the crotch portion of the centre strip and the closure system as it will cooperatively with these elements provide a snug fit around the upper thigh. The leg closure systems as may be made by tapes or by the side seam will inevitably pull the inwardly folded area of the centre strip outwardly and against the inner leg, thus forming an essentially triangularly shaped folded over area 1058 at the lower edge of the folded over side panel attachment area, such that this triangle 1058 is positioned with its inner surface against the inner leg. As indicated in FIG. 2C this generates a snug fit around the leg, maintaining good contact between the leg and the centre strip side areas.
Thus, a product design according to the present invention allows to broaden the selection of side panel and backsheet materials and provides a simple, and well fitting design compared to conventional and to the recently published “body conforming” articles.
Instead of folding the centre strip and combining it with an unfolded side panel, the skilled reader will readily recognize for particular embodiments that the double pleated fold may be achieved by leaving the centre strip unfolded and combining with a side panel, where the side margins are folded over so as to allow attachment of the respective outer surfaces to each other, as shown in FIGS. 9 (36) to (38), without any limitations to these particular embodiments. Thus, comparing this to the design shown in FIG. 2B (BB)*, the pleat would look as if the other tip of the double pleat would be clipped off.
As shortly described in the above, the side panels may be essentially unitary with the centre strip, i.e. these may be made from the same web material without requiring particular connecting or at least comprise one material, which extends over both regions. In this case, the double pleated longitudinal folding may be executed in two variants, differing in the direction of the fold relative to the inner surface 1020 respectively outer surface 1021 of the article. The “upward Z-fold” can be seen in the lower part of FIG. 5A, which may correlate to the left part of the article during use. It will be mirrored symmetrically in the upper part in the figure, respectively right part in the article. The fold is such that—relative to the centre region around the longitudinal centre line 1005 of the article—the laterally outward regions are folded such that the major topsheet surfaces are upwardly folded onto each other. Conversely, for the “downward inverted-Z fold” (looking like a mirrored “Z” as can be seen in the lower part of FIG. 5B, the major backsheet surfaces are folded downwardly onto each other.
In this case of the unitary design, the general connecting of the centre piece and the side panels can be considered to be already given by this unitary material. In order to affix the pleat, the attachment may be achieved such as by an attachment glue 1120 (see FIGS. 9 A(5) to (9), which may be integral with, identical with, or separate from the contour attachment.
In either of the options as shown in FIG. 5, the attachment of the pleats may be executed as lines but may preferably be executed as connecting regions 1125, thereby creating the bulging effect as described herein above in the context of non-unitary side panels. The butt seam connection as shown for the non-unitary designs is effectively replaced by a further longitudinal fold line 1115 in FIG. 5. The connection between the side panels and the centre strip will form a “butt-type” seam (1110 as indicated in FIG. 2C) for a non-unitary side panel, and a kind of dart-type seam (as known from sewing) for the unitary execution. The two kinds of seam function essentially in the same way—and when pulling the article at its waist circumference, the unconnected parts of the folds will partly unfold along essentially straight or slightly curved lines formed by the side panel and the centre strip connected by the butt-seam or dart-seam. Thus, a butt-type seam looks like a particular execution of a dart-type seam, for which the outer end of the dart is cut open.
It is one particular benefit of the present invention to allow designing shaped articles, where a bulge adopts well to the body contours. A first execution of this embodiment relates to pants-style structures, such as described in general terms in the above. In order to adapt to the shape of the buttocks, the side panel connecting line (1120 in FIG. 2B) is modified so as to form a connecting region 1125 in FIG. 4 in the back region 1018 of the article. As shown, the shape of this connecting region is such that it is wider towards the rear and the front and narrower in the mid portion thereof The front connecting region 1127 in the front region 1012 of the article may be straight, curvilinear, or a differently shaped connection area. Upon unfolding and donning, this particular connecting will create a bulge shape adapting very well to the buttocks and belly of a wearer.
Typically, for articles with non-unitary side panels the width (i.e. across the y-direction of the article) of the connecting regions 1125 and 1127 will be at least 1 mm, and may often be in the range between 5 mm and 60 mm. The rear connection region 1027 may e.g. be shaped such that it is wider in the waist region compared to the crotch or leg region, and even narrower in between. Thus, the distance between the longitudinal centreline and the contour attachment line respectively the innermost delimitation (i.e. closest to the longitudinal centreline) of the attachment region, which forms the first effective pleating, is different in the hip regions than compared to either or both of the waist or hoop regions. For articles with unitary side panels /centre piece design, the attachment line or region may actually be non-continuous between the waist and the hoop regions, i.e. there may be—and for certain designs preferably is—an interruption thereof, i.e. an attachment free region, such as in the hip region. During use, the pleat is in this region then essentially fully unfolded, whilst the pleats in the waist and/or hoop regions are still maintained, the shape contouring in the hip region is achieved with utmost material use efficiency. When present, the CD-width of the attachment lines or regions may often be ranging up to 60 mm.
A particular embodiment of the present invention, which is further explained by referring to FIG. 7, relates to the design of an article 1000, wherein the leg encircling hoop is formed by parts of the centre piece and parts of the side panel material. To this end, the centre piece 1010 may be laid out flat before the folded side panel material 1055 is added. However, in addition to the side panel glue 1120, which connects the side panel to the centre piece and which may be applied in any of the options as described in the above, the side panel is tacked to itself in the side panel tack regions 1170. In the top view of FIG. 7, the centre piece strip 1010 is shown with its outer surface 1021 facing towards the viewer and the user oriented surface 1025 facing away. As described in the above, four pieces of side panels 1055 are folded and connected to the centre piece by side panel glue, here shown as glue lines 1120 along the full length of the side panel, although glue regions maybe used, too. Further, four side panel tack regions 1170 are shown, here shown in a triangular shape, whilst other shapes or even a connecting line such as a glue bead or ultrasonic welding line would be possible. The panel tack regions are preferably delimited by a line corresponding to a “curvilinear fold line”, indicated by the dotted lines 1176 in FIG. 7 (which develops once the article adopts to a three-dimensional shape, such as described in more detail in WO06/102974), and further by the side panel foldline, and a hypothetical line connecting the lateral outward points of the centre piece where the “curvilinear fold lines” terminate. If the connecting extends significantly beyond this region or lines, it may negatively impact the “improved fit function” of the SP. In these tack regions, the folded side panel material is securely connected to itself, which may be achieved by any conventional tools, such as glue application, welding such as by ultrasonic bonding and the like. A narrow, in use overfolded piece of the folded side panel (shown as a white triangle adjacent to bond area 1170) is attached to the centre piece and follows the inner hoop, so it should not be attached to the other surface of the SP. The function of the tack regions 1170 is to allow the forming of leg encircling hoop made up of the laterally outward portions of the centre piece in the crotch region 1172 and the respective portions of the side panels 1174 as indicated hatched in FIG. 7, which will—upon donning and closing—form a right and left hoop fully encircling the leg with an essentially closed force connection line (not shown).
A further embodiment of the present invention relates to a “detached topsheet”, i.e. to articles wherein “topsheet refers to the uppermost layer, i.e. the layer which is positioned towards the wearer and which is intended to be in contact with the skin of the wearer. The term “detached” refers to the fact, that this layer is only partly connected to the base, with at least a portion in the crotch region along the longitudinal centre line being unattached to the base, but is rather connected to the overfolded side margins of the base. Thus, during use, a pick up connection, such as a glue line or dot, lifts the detached topsheet away from the base, thusly creating space for receiving bodily exudates more efficiently. A first execution of this detached topsheet relates to a so called “BM trap” or “secondary topsheet”. Such features are generally known to a skilled person and are described such as in U.S. Pat. No. 5,037,416, U.S. Pat. No. 5,462,541, or U.S. Pat. No. 6,152,907 or copending patent application GB1007486 (unpublished).
Such designs refer to articles, which during use provide a separation of faeces from the skin of the wearer, in particular in the genital region. The present design achieves this separation by including a secondary topsheet in the crotch region, overlaying (towards the wearer) the primary topsheet. This secondary topsheet may be positioned forward and/or backwards of the anal opening during use. It is affixed to the primary topsheet or the base along its longitudinal edges and optionally its front edge and/or rearward edge.
FIG. 3 shows an article 1000 corresponding to the one of FIG. 2 (with respective features being not referenced in FIG. 3), but further comprising a secondary topsheet 1065 which is positioned on top of the primary topsheet 1025 cross-directionally inwardly of the longitudinal fold lines of the centre strip 1007, such that the folded over portions of the centre strip overlay the secondary topsheet (henceforth the perimeter of the secondary topsheet shown as dashed line in the top view). In this design a secondary topsheet fixation glue 1130 is positioned along the longitudinal margins 1064 and the forward margin 1066.
In this design a secondary topsheet pickup glue 1140 is positioned on top of the secondary topsheet. Optionally a secondary topsheet slit or opening 1069 may extend along the longitudinal centre line from the rearward edge forwardly towards the genitals, but preferably not into the area of the genitals. Alternatively, the secondary topsheet may also be fixed along its rearward edge against the primary topsheet. In this case it needs to be equipped with a slit or opening in the anal area.
Upon donning, the snug fit around the legs will appear, but at the same time the secondary topsheet will be lifted away from the primary topsheet by action of secondary topsheet pick up glue 1140, and the side areas close to the slit or opening in the secondary topsheet will be held against the legs of the wearer by the lower side panel areas transferring forces into the inner leg area of the centre strip side areas, thusly creating the aforementioned “BM trap”, which can separate the faeces from the skin and genitals in the mid and front region of the article. The fixation of the opening or slit side margins to the leg surrounding centre strip side areas effectively causes the product width to self-adjust between the legs of the wearer.
In yet a further embodiment the articles comprise a donning aid, which may be a strip of web material, such as described for a secondary topsheet, and which is attached analogously thereto.
A further execution of the “detached topsheet” relates to a unitary topsheet, which is attached to the base in one part of the article, i.e. either the front or the back region longitudinally towards a discontinuity in the crotch region. The discontinuity is preferably executed as a cross-directionally extending cut or slit in the topsheet, but may also be an opening therein. On the opposite side of the discontinuity, i.e. towards the rear or front respectively, the topsheet is not connected to the base, but lifted by the pick up connection. Thereby, an opening is formed during use. If the forward part of the discontinuity is lifted during use, the BM trap, as described in the above may be formed. If the rearward part of the discontinuity is lifted, a urine receiving opening may be formed, particularly adapted to receive urine for a person in a supine position. A skilled person will readily realize, that the base needs to satisfy certain requirements with regard to having a surface adapted to be potentially in contact with the wearer, but also with regard to retaining ingredients such as fluff or superabsorbent materials therein. Also, the liquid handling properties of the layers may need certain adjustments such as with regard to liquid permeability—or lack thereof.
The articles according to the present invention may comprise absorbent elements, whereby the particular design allows particular executions as separate elements may be incorporated. Such absorbent elements are positioned between the outermost layer, often referred to as the backsheet, and the layer, which is positioned towards the wearer, often referred to as the topsheet. A first absorbent element is attached to the outermost layer at least in the crotch region, whilst a second element is attached to the innermost layer at least in the crotch region such that in the in-use configuration the second element is lifted away at least in a portion along the longitudinal centre line. Thus, as described for the detached topsheet, an opening may be formed during use such as for receiving faeces, if the secondary core is terminating in the perineal region and extends forwardly. Similarly, the secondary core may terminate in the perineal region during use but extend rearwardly, such that it can readily receive urine loading e.g. in a back-lying position of a wearer. In such variants, the secondary core may also function like a stiffening element as described herein above.
When considering the projection of the first and second absorbent elements onto the outermost layer, they may overlay, overlap in the crotch region or be spaced apart, though a gap in this projection should not be excessive.
Generally, there are no particular requirements for the absorbent elements. The first and the second absorbent element may be of the same type of material, and may—for example—be off the same roll of absorbent material.
In a particular execution the first and a second absorbent element are positioned onto a carrier web, such as a nonwoven web, which may be suitable as topsheet. The first and the second element may have be cut and spaced off a single roll of absorbent material. Alternatively, they may come from two different rolls, and may have different composition and/or dimensions. In a further alternative, one or both of the elements may have be formed “on-line”, such as by a conventional core forming apparatus. The two elements may be positioned onto one web carrier or two web supports, which may move at differential speed, such that the leading edge of the slightly faster moving trailing element may have overlapped the trailing edge of the slightly slower leading element, such that the two elements are delivered to the other elements of the articles in an overlapping (or shingled) positioning. The carrier web between the elements can be folded in the longitudinal direction in a Z-folded manner. If the two elements are placed in the “detached topsheet” design as described in the above, and one of the elements is connected to the base in the crotch region whilst the other one is lifted, the carrier may form the opening and may be adapted to allow passage of liquids, like urine of faeces to penetrate through, such as by longitudinally extending slits between the elements. The cross-directionally extending edges of the elements may be straight in the cross-direction, but alternatively, they may have varying shapes, such as rounded, or angled, or chevron like. A skilled person will readily realize that also the trailing edge of the leading element may overlie the leading edge of the trailing element. A further particular embodiment of the design has side panels, which are connected by a so called “perf\'n pop” feature. This refers to a connection between a first and a second side panel, which can withstand the processing/manufacturing steps, but which can be readily separated by a user e.g. upon donning. Alternatively, this connection may already be separated at a final process step in the manufacturing. A “perf\'n pop” connection as such is well known for a skilled person. Typically, it is produced e.g. by treating a material such as by an interrupted separation line. Whilst some product options produced by such perf\'n pop processes may not show any difference in use as compared to products made from separate side panels, this design offers more process flexibility, particularly as far as side panel design options are concerned.
In any of the options for the side panels, these may be made of a single material, or a composite material. Such a material may have varying properties, such that strength or elasticity is higher e.g. in the waist region than in the crotch or leg region. Such a composite may be a multi-layer design, such as elastic strands being affixed between non-woven materials. Such a composite may also be composed of materials having differing properties in a side-by-side arrangement, optionally connected to each other by a butt type, or an overlapping connection.
It should be noted, that they are variants of the present design principle, which are considered to be covered by the present invention.
Instead of the two tape system shown in the above, the article may comprise a multiplicity of tapes, or a single tape system. Optionally, two tapes may be connected at their distal ends, whilst the opposite ends are connected to the waist and the leg regions respectively.
Further, the article may comprise leg elastics extending longitudinally, which may be sandwiched in a conventional way between topsheet and backsheet adjacent to the longitudinal margins. Optionally, the elastics are folded into foldlines along the lateral margins of the secondary topsheet, or sandwiched between the secondary topsheet and the wearer facing surface of the base.
Further, the topsheet and backsheet materials may have differing widths, and one material may be folded along a further longitudinal folding line over the longitudinal edge of the other material.
Optionally, the topsheets may comprise a skin care composition, such as a lotion as well known in the art.
In yet a further embodiment, pants or pants-style articles may comprise leg hoops, such as described in general terms in WO06/102974. FIG. 6 shows an article corresponding to one as shown in FIG. 2 (and hence duplicate numerals are partly omitted), additionally showing leg hoops 1160, which are folded over in their crotch region 1165 positioned in the crotch region 1015 of the article, such that a first leg hoop surface 1161(hatched) is visible in FIG. 6, but are not folded over in the outwardly extending front 1162 and rear 1168 extensions, where the opposite leg hoop surface 1169 can be seen in FIG. 6.
In a second aspect, the present invention relates to the manufacturing of absorbent articles, which may be well employed for producing certain articles described above especially at high production speed. It is a particular benefit of the invention that for many of the embodiments shown, all components forming the precursor/article can be stacked up such that they do not exceed the limits of the centre piece. This allows respective machines to generate an output of 600 to 2400 pieces per minute, at web speeds of about 300 m/minute, or even more than 1000 to 4000 articles per minute, corresponding to manufacturing web speeds of more than 500 m/minute, for articles with a length of around 500 mm.
It is well known in the art, that articles may be produced such that the orientation during production is aligned with the longitudinal direction of the article during use (“MD process”). Alternatively, in the so-called “CD process” the machine direction during production is perpendicular to the longitudinal orientation of the article during use.
Whilst the present invention is applicable to both a MD- and a CD- process, it should be noted, that for the purpose of the present explanation, the terms “longitudinal” (or x-direction), cross-directional (or y-direction), “inner” surface respectively direction, “opposite” surface respectively direction are defined in relation to a ready to use article, as described in the above.
The process of manufacturing comprises the step (a) of providing one or more essentially endless webs, which are to be converted into the articles. A first web may comprise an essentially endless series of segments such as pre-forms of articles, still being connected to each other. These pre-forms may essentially have all required elements or components to form the articles, or some components may be added in course of the described process or thereafter. Thus the first web may comprise one or more centre strips. One or more second web(s) may be provided from which the side panels can be formed. Each of the pre-forms has a front, a rear, and a mid region corresponding to the orientation during use.
In the MD process variant, the front regions of the article may correspond to a leading or trailing portion of the web segments. For simplicity, the present discussion assumes that a front region corresponds to a leading portion of the segments of the web.
In the CD process variant, the front regions of the article may correspond the a left or right portion of a segment of the web, and the leading and trailing portions of the segments of the web correspond to left or right portions in the product. In case of a dual-lane setup, a centre piece strip may be twice as wide (in the MD variant) or twice as long (in the CD variant) as the respective centre piece in the finished article.