ITTO20130594A1 - PROCEDURE FOR MANUFACTURE PRE-CLOSED ABSORBENT HYGIENE-HEALTHCARE ARTICLES AND PRE-CLOSED HYGIENIC-HEALTH ARTICLE - Google Patents

Description

â € œProcedure for manufacturing pre-closed absorbent sanitary articles and pre-closed sanitary articlesâ €

TEXT OF THE DESCRIPTION

Field of invention

The present invention relates to absorbent sanitary products and has been developed with particular attention to the possible application to pre-closed absorbent sanitary products, wearable as panties.

A typical example of absorbent sanitary products of this type is represented by baby diapers commonly referred to as â € œtraining pantâ €.

Description of the state of the art

For many years now, the solution adopted almost uniformly by all manufacturers in the sector has been to create these products in the form of shaped elements according to a general hourglass conformation, with a central body in which there is a composite structure absorbent designed to absorb body fluids and two parts of the anterior and posterior extremities respectively, which extend laterally. The product is worn giving it a general U-shape and bringing the median section of the central body up to the area where the user's legs are inserted. The end parts are extended around the user's waist by connecting the side edges opposite each other by means of adhesive labels, or stickers, normally repositionable, or similar closing elements, in such a way as to be able to close the product around the body of the user.

These products have traditionally been manufactured and sold in an open condition, that is, leaving it to those who apply the product the task of arranging it around the user's body and closing it according to a general panty conformation in the terms mentioned above.

Over the last few years there has been a renewed interest in diapers of the type currently known as â € œtraining pantâ €. These are diapers of the type illustrated, for example, in US-A-4,610,680, intended to be packaged and sold in a pre-closed condition. As extracted from the package, the product has a conformation substantially similar to that of a panty. The pre-closed product is worn by sliding it along the user's legs according to criteria essentially similar to those followed for wearing a panty. Taking into account the specific use for which the pre-closed product is intended, it is then envisaged that the product can be removed without having to slide it again along the legs of the user.

To this end, the pre-closed product can be made in such a way that it can be torn apart (according to the criteria illustrated in the document US-A-4,610,680), or by ensuring that the pre-closed product can be opened along the sides of the life line, i.e. in correspondence with those that can be defined as the `` side flaps '' (as is the case for traditional diapers, packaged and sold in an open condition), for example by providing for the use of adhesive labels or stickers , of button panels, groups of push buttons or, according to a particularly successful solution, providing for the use of micro-hook closure structures (also called â € œVelcro closuresâ €).

The use of these closure elements must be combined with the need, to which reference was already made, to ensure that the â € œtraining pantâ € diaper is made and packaged in a closed condition, so as to to wear it like a normal panty.

Various patent documents deal with the problem of applying these closure elements in the context of an industrial cycle that can be implemented with the high production rates typical of the sector.

For this purpose, reference can be made, for example, to documents US-A-5,855,574, US-A-6,210,388, US-A-6,409,858, US-A-6,477,628 and US-A-6,461,344.

These documents, which however do not exhaust the overview on the subject, address the problem of the application of the aforementioned closing elements, bringing primary attention to the functionality of the final product.

At least some of these documents naturally take into account the need to manufacture the related products with the typical cadences of industrial manufacturing. For this reason they suggest, in different ways, to resort to continuous manufacturing processes, in which the products are built starting from the single component parts, preferably operating on a continuous chain of products destined to be separated from each other, thus arriving at the formation of single products only in the final stages of the process.

However, especially as regards the application of the aforementioned closing elements, the solutions described in these previous documents do not take into due account various problems likely to assume considerable importance both at the level of realization and at the level of use of the products in question.

First, the application of a closure element (or part of such element) on a belt, web or chain of sanitary products in the course of manufacture, with said belt, web or chain moving with a linear speed even quite high, it can expose the aforementioned element, when the same is not completely anchored to the tape, the web or the chain on which it is applied, to waving phenomena, capable of causing the element itself is positioned incorrectly for subsequent processing operations, in particular as regards possible cutting operations.

In addition, it is necessary to take into account the fact that the cutting operation intended to separate the individual sanitary products, or the type of connection of the side edges used, can lead to the formation of friction elements or surfaces which, if not adequately shielded, they can be at the origin of inconveniences that can even be rather annoying, for example skin irritation or lacerations, because they are directed directly towards the user's body.

Again, it is important to avoid that the user (think typically of a child, even a very small one) can, with the application of even a modest force, open the flaps on the hips and cause the unwanted opening of the € ™ closing element, in particular in the case of absorbent products designed to be resealable.

Several patent documents specifically address the problem of making sanitary products that are pre-closed (ie closed), resealable and repositionable. Examples of these documents include, for example, US-A-2004/0225271, WO-A-2004/098478, EP-A-570 980, US-A-2004/0186451, US-A-2004/0193135, WO-A- 03/024377, WO-A-03/024372 and WO-A-03/003923, and WO-A-01/70155.

These state-of-the-art provisions of pre-closed sanitary products do not, however, ensure truly satisfactory results for at least one of several reasons, namely:

- in some cases, the “front” and “rear” portions of the product are connected to the lifeline by tab elements, which are partially or completely arranged inside the product; if not properly shielded, they can cause skin irritation or lacerations, as they are directed directly towards the user's body;

- to be satisfactory, the repositionability characteristic (i.e. the possibility of varying the position to which the front and rear portions of the product lifeline are connected) should preferably be obtained by acting on tab elements extending from the rear portion of the product lifeline, and can be selectively connected in different positions on the front portion; the opposite arrangement is in fact decidedly impractical;

- in still other arrangements, the front and rear portions of the product lifeline are connected by welding areas in the form of lateral â € œfinsâ €, which protrude radially from the product; these protruding fins represent an important negative factor in products such as â € œtraining pantâ €, which try to reproduce as much as possible the appearance of normal panties; furthermore, these protruding fins may possibly favor an unwanted opening of the product by the user;

- a further factor to be taken into consideration consists in the fact that the sanitary products in question can consist not only of baby diapers but also of pads for incontinence in adults, essentially in the form of enlarged versions of baby diapers ; the respective packages of these adult products tend to be excessively large in size.

The state of the art also includes European patent application EP-A-1 523 968.

Purpose and summary of the invention

The object of the present invention is to provide an arrangement capable of ensuring a truly satisfactory solution to the problems set forth above.

According to the present invention, this object is achieved thanks to a pre-closed sanitary article defined in claim 4 and to a process for making a pre-closed sanitary product defined in claim 4.

The solution described at the same time leads to the manufacture of a pre-closed sanitary product in which, among other things:

- the front and rear portions of the product are connected at the lifeline by tab elements which are completely on the external side of the product, not exposed towards the user's body; consequently, these connecting / closing elements are absolutely not capable of causing skin irritation or lacerations on the user;

- the reclosability / repositioning feature is obtained by acting on the tab elements that extend from the rear portion of the product lifeline, and can be selectively connected in different positions on the front portion, thus making it possible to adjust the length of the line life of the product, with the aim of â € œadaptingâ € the product to the size and habits of the user;

- the front and rear portions of the product are connected at the lifeline through connecting / closing elements which are completely â € œleveledâ € (i.e. free of noteworthy protrusions) with respect to the external surface of the product, ensuring that the product has a completely similar appearance to the appearance of normal panties;

- the product, in the form distributed to the public, can be folded to reduced dimensions; this allows a corresponding reduction in the size of the relative package, which is particularly advantageous and appreciated in the case of pads for incontinence in adults. In addition, the product in the folded form has a small portion of its internal surface facing outwards.

Brief description of the drawings

The invention will now be described, by way of non-limiting example only, with reference to the attached drawings, in which:

- figure 1 is a general perspective view of a sanitary product as described at the same time;

- figure 2 is a cross-sectional view along the line II-II of figure 1;

Figure 3 is a general perspective view of an alternative embodiment of a sanitary product;

- figure 4 is a schematic and partial representation of a part of the manufacturing process of a sanitary product as illustrated in figure 3;

Figure 5 illustrates a closure element applicable to two sanitary products of the type illustrated in Figure 1 or Figure 3, included in a chain of products during manufacturing;

- figure 6 is a schematic representation of a part of the manufacturing process of a sanitary product as illustrated in figure 1,

Figure 7 illustrates the resulting product of the process steps illustrated in Figure 6;

Figure 8 is a cross-sectional view along the Y-Y line of Figure 6;

- figure 9 is a cross-sectional view along the line IX-IX of figure 7;

- figure 10 is a representative view of how it is possible to package a product according to the present invention;

- figure 11 is a representative view of how a product according to the present invention can be deployed to be worn by the user, and

- figure 12 is a representative view of a package of sanitary products, arranged as shown in figure 10.

Detailed description

In figures 1 and 3, pre-closed absorbent sanitary products of the type currently called â € œtraining pantâ € are indicated as a whole with reference 1.

Essentially, the manufacture of such a pre-closed product involves the manufacture of a blank or â € œblankâ € in the form of a flat element, formed for example with a general hourglass configuration, with a central body 2, in which it is foreseen an absorbent composite structure designed to absorb body fluids, and two extremity parts, one front 3 and one rear 4. The hourglass-shaped flat element is then given a general U-shaped or V-shaped configuration, as illustrated in figure 1, bringing the middle section narrower than the central body 2 (contextually called â € œforking portionâ € of the product) up to the area where the user's legs will be inserted during use.

The front and rear parts 3 and 4 are connected at their opposite side edges to form a pre-closed, i.e. closed, annular waist portion, whereby the product 1 assumes a general shape resembling the typical form of normal underwear. In this way, the product is suitable for wearing by a user, with the central body 2 extending on and around the user's â € œcrotchâ € area, while the waist portion formed by the front and rear 3 and 4 connected at their opposite side edges surrounds the user's waist.

On the basis of manufacturing criteria that are well known to those skilled in the art, the hourglass-shaped blank from which product 1 is obtained can typically consist of:

- a top or inner sheet (compared to the normal conditions of use of the product 1) permeable to liquids, usually called â € œtopsheetâ € (TS), on which a pair of elasticized side barriers can be placed, indicated with 6 in figure 4 , which extend in the direction from one of the edges of the topsheet to the opposite edge, and a pair of elastic or elasticized formations, indicated with 5 in the attached figures, placed centrally on the ends of said edges, in a direction orthogonal to said elasticized barriers;

- a backsheet (BS) impermeable to liquids, i.e. a lower or external sheet or laminate (compared to the normal conditions of use of the product 1), on which a pair of elastic or elastic formations can be arranged, indicated with 7 in figures 1 and 3, extending in the direction from one of the edges of said backsheet to the opposite edge; And

- an absorbent structure (AS) to absorb body fluids, enclosed, ie sandwiched, between said topsheet and said backsheet.

Those skilled in the art are well aware that the elements just described constitute a fundamental structure, to which other additional elements can be added according to design principles well known in the field.

For example, the elastic or stretch formations (see point 5 in figures 1 and 3) are typically arranged centrally on the ends of the topsheet edges, with the aim of ensuring the adherence of the diaper's waistline to the abdomen of the user, while the elastic or elastic formations (generically indicated by 7 in figures 1 and 3) that extend in the direction from one of the edges of the topsheet and / or the backsheet to the opposite edge have the purpose of ensuring adherence passages for the legs to the user's legs.

Naturally, as is known to those skilled in the art, a substantially equivalent structure for an absorbent sanitary product of the pre-closed type can comprise, as illustrated by way of example in Figure 3, a central body 2 and two front end parts 3 and rear 4 distinct from each other and joined together with known means to form article 1. In this case the central body 2 can typically comprise an upper or inner sheet permeable to liquids, or topsheet, a lower or outer impermeable sheet to liquids, or backsheet, and an absorbent structure enclosed between them. The two parts of the front 3 and rear 4 ends can be made up of a sheet or a laminate. The product illustrated in figure 3 can also comprise additional elements similarly to what has already been described in relation to the product illustrated in figure 1, such as for example elastic or elasticized formations and / or barriers 7 which extend along the lateral edges of the central body 2, for ensure the adherence of the passages for the legs to the user's legs, and elastic or elastic formations 5 arranged on the front 3 and / or rear 4 extremities, with the aim of ensuring the adherence of the life line to the body of the user. In particular, the product illustrated in Figure 3, typically obtained from the chain of blanks illustrated in Figure 4, shows the elastic or elasticized formations 5 which extend substantially over the entire surface of the two front end parts 3 and rear 4, unlike of the product of Figure 1, where the elastic or elastic formations 5 extend substantially near the waist edges of the front 3 and rear parts 4. In general, in a pre-closed sanitary product according to the present invention, such as for example illustrated in figures 1 and 3, it is possible to identify for each component element of the product a topsheet or internal surface, such as the surface that, in use, faces the user's body, and a backsheet or external surface , such as the surface which under normal conditions of use is turned towards the outside, regardless of whether these surfaces correspond a distinct sheet of material, for example typically a backsheet or topsheet material, or the respective internal or external surface of a single sheet of material.

Similarly to what was previously described, a pre-closed sanitary product in the alternative configuration illustrated in Figure 3 can be made starting from a chain of blanks or â € œblankâ € as illustrated in Figure 4, which can typically be processed according to a process analogous to what is illustrated in figure 6, and as will be described in greater detail below.

In the finished pre-closed product 1, the front and rear parts 3 and 4 are connected at their mutually opposite side edges to form an annular closed waist portion of the product 1, typically by means of label connection / closure groups indicated at 10 , which have a generally stratified structure, which will be described in greater detail below. One of these groups 10 is provided at each side (left-right) of the waist region of product 1, respectively.

In addition to ensuring that product 1 - which intends to be of the â € œpre-closedâ € type â € “as presented to the user (and as initially worn by the user) is â € œclosedâ € around to the waist portion as standard panties, groups 10 typically allow the product to be opened when it is worn (for example to check if the user is still dry or clean), then being able to close it around the user's body, also adjusting the length of the waist portion to adapt in the best way to the size and preferences of the wearer.

Figure 6 illustrates hourglass-shaped flat elements (â € œblankâ €) of the type described above (including an absorbent AS structure sandwiched between a topsheet TS and a backsheet BS), and substantially corresponding to the finished product illustrated in Figure 1, connected with a cross arrangement in a chain. As will be clear to those skilled in the art, the absorbent structure AS closed between topsheet TS and backsheet BS is schematically represented in a simplified way in figure 6, but it can include further elements, such as for example elasticized side barriers of the type indicated with 6 in figure 4 , where the absorbent structure is represented in more detail, highlighting its constituent elements. Specifically, Figure 6 illustrates a chain of these hourglass-shaped blanks, which advance from left to right and undergo cascade forming and machining operations, which lead to the formation of a chain of panty-like products.

As indicated, the general hourglass configuration of the blanks or blanks that make up this chain is the result of the generally enlarged shape of the lateral extremities with respect to the sides of the central portion (or the area that remains adherent to the body) of each sanitation product. In each product there are parts S, which are carved according to a general arched pattern (ie the notches where the legs are introduced); these are the parts which, in product 1 closed to form a pair of panties, constitute the openings for the user's legs.

The blanks are joined together at the lateral ends of the front and rear portions to form the chain. For this reason, in the chain of blanks represented at the top left in Figure 6, the notched parts S of the adjacent blanks are joined together to form approximately elliptical openings in the otherwise continuous body of the chain itself.

As will be clear to the person skilled in the art, the process described here can be modified in a known way and adapted to alternative embodiments of the pre-closed sanitary article to be worn like a panty, such as the product 1 having the configuration illustrated in figure 3, typically obtained from a chain of blanks as shown in figure 4.

In a first folding station (indicated schematically with 100, and of any type known for the purpose in the sector of the manufacture of sanitary articles), the external ends of the backsheet BS are folded towards the inside of the chain of blanks or blanks, to â € œcatchâ € the corresponding ends of the absorbent structure AS and of the topsheet TS on the opposite longitudinal sides F1 and F2 of the chain. The elastic elements 5, indicated in figure 4 and also in figure 6, can be applied in one of the ways known in the art, not illustrated for simplicity.

In two successive bending stations, in the positions indicated schematically as 104 and 106, the chain of blanks is subjected to two further bending operations. In the additional bending operations carried out in point 104 and point 106 the longitudinal sides F1 and F2, and therefore the end parts 3 and 4 of the blanks in the chain, are folded towards the inside of the blanks, in particular towards the portion of â € œcrotchâ € (ie the portion between the leg openings), ie the end parts 3 and 4 of the blanks in the chain are folded against the inner or topsheet surface of the crotch portion. This takes place along fold lines B which are located approximately halfway up the vertical height of the finished product 1 (see also Figures 1 and 3). The additional folding operations performed at points 104 and 106 give the products in the chain a general so-called C shape, as best seen in the cross-sectional view of Figure 8.

Typically, after the bending operation performed at point 100, a first element or component 10a of the closing assembly 10 is applied on the side F2 at point 108. The application of the component 10a on the side F2 takes place, in a known way, for example by adhesive or thermal bonding. A second element or complementary component 10b of the connection group 10 is similarly applied, for example, to the point 109 on the flank F1. With reference to the embodiment illustrated in Figure 6, and with respect to the observer's point of view, the first and second elements 10a and 10b of the connection assembly 10 are applied respectively on the sides F2 and F1 of the chain of blanks facing towards the bottom, that is, in other words, on the underside of the chain of blanks. The sides F1 and F2 are subsequently brought to face upwards, as a consequence of the bending operations carried out at points 104 and 106.

It will be easily noted that `` upwards '' and `` downwards '' are used at the same time to facilitate the understanding of the present description, and in no way should they be interpreted in a limiting sense of the scope of the invention: in fact, The bending / forming processes illustrated in Figure 6 can be performed in any orientation in space.

In a further bending station (indicated schematically by 106, and again of any type known for the purpose in the sector of the manufacture of sanitary articles), the chain of blanks is subjected to bending to form a U-shape ( or of V) in the central region, i.e. in the crotch portion 2, which ultimately leads it to assume the C-shape folded on itself, as illustrated in the cross-sectional view of Figure 9 relative to the single product 1 obtained from the chain itself . The bending operation carried out at point 106 brings the opposite longitudinal sides F1 and F2 of the chain, and therefore the respective end parts 3 and 4 of the blanks, to overlap each other, in such a way as to form (based on the criteria described more clearly later) the lifelines of the individual products 1. At the same time, the carved parts S form the passages for the legs in the products themselves.

The various folding operations described above can typically be performed by means of a folding machine which is itself well known in the field of sanitary products. Essentially, these bending machines are capable of running on a moving chain of advancing products, and include a plow forming unit, with a straight bending bar `` ploughshare '', schematically illustrated and indicated with 1001 , 1002 and 1003 in figure 6. The central element of the 'plow' defines the bend or fold line of the fold and the lateral formations that complete the bending movement on either side of the fold line.

Essentially, the purpose of the bending operations performed at point 102 (bending bar 1001) and at point 104 (bending bar 1002) is to â € œcloseâ € the longitudinal sides F1 and F2, therefore the end parts 3 and 4 of the blanks in the chain, and fold them inwards towards the “crotch” portion (ie the portion between the leg openings). This takes place along a folding line B which is approximately halfway up the vertical height of the finished product 1 (see also Figures 1 and 3). The subsequent folding operation performed at point 106 (folding bar 1003) gives the products in the chain a general C-shape closed on itself, as can be seen better in the cross-sectional view of Figure 9.

As a consequence of the folding operation performed at point 106, the two complementary closing elements 10a and 10b are brought into a face-to-face relationship, and are made to adhere (i.e. are connected) to each other, thus `` closing '' the products 1 along their lifeline.

Reference number 110 indicates a pressing device (which includes for example two rollers with reverse rotation) which presses the closing elements 10a, 10b against each other, thus reinforcing the connection between them.

The chain of C-shaped products folded back on itself is finally subjected to a cutting operation, implemented for example in a cutting station, indicated by 112, of a known type, and typically comprising a cutting cutter with a rotating blade . The cutting station 112 operates along a line identified by X-X in figure 6. The same indication appears, for reasons that will become clearer from the following, also in figure 5.

The cutting operation carries out the separation of the products 1, which therefore take on the appearance of single products, which are intended to be sent to a packaging station (not illustrated but of a known type).

The products 1, at the end of the cutting operation performed at the cutting station 112, have the general appearance shown in figures 7 and 9, that is, they are folded with a C-shaped arrangement folded back on itself, with the two end parts 3, 4 folded inwards and flexed around the respective folding lines B against the crotch portion 2, so that the two end parts 3, 4 are one against the other the other at homologous side edges facing each other, with the closing groups 10 sandwiched together. In such an arrangement, the front and rear portions 3, 4 are â € œclosedâ €, that is, folded inwards against the inner or topsheet surface TS of the crotch portion 2, and in effect arranged in the middle of the U-shaped (or V) folded crotch 2, with the respective internal or topsheet surfaces TS facing at least partially towards the internal side of the product 1, i.e., as shown in Figure 7, where they face the internal or topsheet surface of the crotch portion 2, and the respective external or backsheet surfaces BS facing each other and connected by the closing elements 10a, 10b.

The closing elements 10a, 10b allow, in the embodiment illustrated, the implementation of the detachment and new closure function of the product 1, according to methods which allow the identification of the product 1 as pre-closed, detachable and reclosable.

Those skilled in the art will understand that the characteristics and folding methods of the products 1 and the application of the closing elements 10a, 10b (as further described in detail below) are largely independent of the specific characteristics of the embodiment. of products 1. This applies, in particular but not exclusively, as regards the structure (or `` construction '') of product 1, i.e. with regard to the characteristics such as the composition of the backsheet BS and topsheet TS, and of the layers and auxiliary formations normally associated with them, etc.

It will be noted that in the folded C-shape folded on itself illustrated in figure 7, the product 1 has a length P determined by the â € œpassâ € of the cutting operation performed at point 112. The step in question essentially corresponds to the â € œstepâ €. “width” of the front and rear portions 3 and 4 along the user's lifeline, ie approximately half the length of the user's lifeline. In fact, the length P of the product as illustrated in Figure 7 refers to the stretched product, that is to say with the elasticized elements 5 associated with the lifeline of the product (see also Figure 1) kept under tension. In reality, the actual length of the packaged product in the folded or pre-folded condition is at least slightly smaller than the step in question, thanks to the action of the 5 elastic elements associated with the product's lifeline (see 5 in figure 1) which tend to shorten or contract the product. In particular, as will be explained in more detail below, where the action of the elasticized elements 5 is particularly pronounced, for example if they extend substantially in correspondence with the entire surface of the respective front 3 and rear 4 extremity parts, as in the product illustrated in Figure 3, the length of the folded or pre-folded product in a relaxed configuration for packaging is typically less than the length P determined by the pitch. In a particularly preferred embodiment, this length can correspond approximately to the width of the crotch region 2, with the front and rear end regions 3 and 4 substantially retracted inside the crotch region 2 folded into a U (or V) shape, as shown in Figure 10 and explained in more detail below.

On the contrary, the â € ™ heightâ € of the C-folded product folded on itself, that is, the distance between the B-fold lines and the crotch portion 2 in correspondence with the U (or V) fold line, Ã It is equal to a length L3, which is approximately half of the length L2 of the preformed product after the bending operations performed at points 102 and 104 (see figure 6).

The length L2 is in turn approximately equal to half the total length L of the product, measured between the flanks F1 and F2 in the enlarged and flattened product (see again figure 6).

It will be noted that in the exemplary arrangement described here, the C-folded products folded on itself can be grouped to form stacks, which can be inserted into respective box or bag packages of a known type, such as the package 120 illustrated by way of example in figure 12.

Figure 10 shows in particular a stack of products 1 folded, or pre-folded, and grouped for packaging, of a type corresponding to the product illustrated in Figure 3, that is, showing the elasticized elements 5 substantially extended to the entire surface of the respective parts of the front and rear ends 3 and 4. The products correspond in particular to that shown in Figure 3, and in this case, as explained above, the action of the elastic elements 5 on the product 1 in the folded and relaxed condition makes ¬ that the parts of the front 3 and rear 4 ends joined together are substantially retracted inside the crotch region 2 folded in a U (or V) shape. In this way the approximate width Pâ € ™ of the stack is significantly smaller than the width P of the fully extended product, determined by the production step, and can approximately correspond to the width of the forking portion. Such an arrangement has a twofold advantage. First of all, the product in a folded and relaxed condition for packaging has a smaller lateral footprint, which allows for the creation of smaller packages. Secondly, the product in the folded and relaxed condition has an extremely small, if not entirely negligible, portion of its internal surface, or topsheet surface, in particular of the front and rear end parts 3 and 4, facing the Exterior, thus reducing the risk of contamination of said surface destined, in use, to come into contact with the user's body.

As illustrated schematically in Figure 10, these stacks can have a width approximately equal to Pâ € ™, a height approximately equal to L3 and a length A given by the number of products 1 in the stack. Example values of Pâ € ™, L3 and A are respectively 130-150 mm, 130-140 mm and (in the case and example of a package with 16 pieces) 320 mm, respectively.

Note that a value of 130-140 mm for L3 also allows for a significant reduction in package size compared to standard packages, including U- or V-folded products.

The products 1 can be removed from the package and handled by the user in the C-folded configuration folded on itself illustrated in figure 11, i.e. by opening the front and rear portions 3 and 4, and consequently necessarily also the corresponding front and back of the crotch portion. In particular, figure 11, compared with figure 10 with the products 1 grouped for packaging in a folded and relaxed condition, shows the front and rear end parts 3 and 4 already extracted at least partially laterally outside the folded crotch portion U (or V). The upper sections folded inside the front and rear portions 3 and 4 can then be unfolded upwards, as illustrated schematically by the two arrows in figure 11. In this way the product 1 is brought back to its desired panty configuration , similar in this case to the product illustrated in figure 3, after a sort of â € œextroversionâ € movement of the C-folded product 1 folded back on itself when packaged. At this point it is possible for the user to insert the legs into the openings S.

It will be noted that the “extroversion” movement just described brings the connecting / closing elements (groups) 10 back to the outside of the product, which avoids any unwanted interaction with the user's skin.

In a possible alternative arrangement (not illustrated), the `` extroversion '' movement just described can be performed automatically (by known means) at the end of the manufacturing process, schematically represented in figure 6. In that case, the movement just described that brings the connecting / closing elements (groups) back to the outside of the product 1 is performed before the product is packaged. The advantages described above in terms of size reduction are not obtained if this possible alternative arrangement is used, as the products are packaged exactly as standard pre-closed products are currently packaged. An advantage for the user is in this case that the user no longer has to perform the `` extroversion '' movement, as the connecting / closing elements (groups) 10 are already on the external side of the product when it is extracted from the package.

The process described with reference to Figures 6 to 9 allows an efficient manufacture of hygienic products of the panty type, which are closed along the lifeline by elements (groups) of connection / closure 10 with tabs, destined to be finally arranged at the € ™ exterior of the product.

Experts in the field will easily notice that the use of such a procedure is by no means limited to the connecting / closing elements (groups) 10 which:

- they are composed of complementary elements 10a, 10b applied on one of the sides F1 and F2 and then connected following the completion of the folding process in the shape of a C folded on itself of the products,

- when they are applied on the advancing chain of the preformed product, they actually comprise (as explained in more detail below) two symmetrical portions or parts, which ultimately are intended to be cut along the X-X axis, to form two sections which then act as connecting / closing elements for two adjacent products 1 in the chain, after these products have been separated to manufacture individual products 1 (cutting station 112 of Figure 6).

Specifically, the solution described with reference to figures 6 to 10 can be used, among other things, with reference to closing / fastening elements which:

- they are made up of a single component, applied on one of the sides F1 or F2 and subsequently fixed to the other of the sides F1 or F2 when the process of folding the C-shaped folded on itself of the products 1 is completed, also by means of permanent fastening systems, for example by means of adhesive or heat-sealing, that is, open only by tearing the closing / fastening element, but not reclosable and repositionable, and / or

- they are applied (as a two-part group, or as a one-part group, as explained above) as single pieces on a respective product 1 at one end of a portion, the front and / or the rear and, in as such, they are not subjected to any cutting action at point 112.

The folding process in the shape of a C folded back on itself exemplified in figure 6 is applied to a chain of products 1 worked in a `` crisscross '' way, i.e. with the individual â € œblankâ € configured as an hourglass that extend crosswise with respect to to their direction of advancement. The same process can be applied (using known means) also to products processed in the `` direction of the machine '', i.e. to a chain of products connected through the extremity regions of the front and rear portions 3 and 4, i.e. with the hourglass-shaped individual â € œblankâ € that extend lengthwise with respect to their direction of advancement.

Naturally, as will be clear to those skilled in the art, what described above can be applied with routine modifications to the production process of a pre-closed sanitary article having end parts 3 and 4 and a crotch portion 2 with an alternative structure compared to that illustrated in Figure 1, such as the product illustrated in Figure 3, with the end parts 3 and 4 distinct from the fork portion 2, obtainable from a chain of blanks as illustrated in Figure 4.

In the exemplary embodiment illustrated here, the connecting / closing elements 10 (hereinafter the possible segmentation into two components 10a, 10b will no longer be explicitly mentioned for the sake of simplicity) are subjected to cutting when the chain of products illustrated in figure 6 is subjected to cutting along the line X-X at station 112. The elements 10 are also cut along a median or basically median plane, thus being divided into two parts or halves. Of these halves, a first half remains associated with the end B1 of a product 1, by connecting the two corresponding sides F1, F2, and a second half remains associated with the end B2 of the immediately adjacent product, also in this case by connecting the two corresponding sides F1, F2.

If we look in particular at product 1, which can be seen in the far right part in figure 6, we can understand how the closure of the lifeline of the product in question is ensured, at the end B1, by means of the first half of an element 10 and, at the end B2, by means of the second half of another element 10, which was previously cut in station 112.

Similarly, in product 1 immediately following, the closure of the lifeline is ensured, at the end B2, by the second half of the element 10, the first half of which closes at the end B1 the product more valley and, at the end B1 (actually not visible in the drawings, as this end is shown while it is still completing the folding process with a general C shape folded on itself of the product), from the second half of another Item 10.

Figure 5 represents a possible embodiment of closing elements in the form of endless strip elements, comprising two symmetrical portions which can be separated by performing the cut along the X-X axis. Such a strip element can be segmented to make two closure elements 10 (possibly including two complementary portions 10a and 10b) which can be applied on a chain of products 1 as illustrated in figure 6, and then cut (at point 112) along the X-X axis, to manufacture two separate portions, which serve as closure / fastening elements for two adjacent products 1. For additional details and alternative embodiments on the possible use of these strip closure elements, please refer to to the European patent application EP-A-1 523 968, already cited above.

The embodiment of the closing element 10 represented by way of example in Figure 5 corresponds to a basic configuration that can be used in the product 1 illustrated in Figure 1 or in Figure 3.

The closing element 10 shown in Figure 1 or 3 comprises as a basic component a strip of laminar material, for example a non-woven fabric, for example of the type normally called SMS, folded according to a general omega configuration.

In practice, the strip in question includes:

- a base branch 11, which extends basically symmetrically around the imaginary line X-X, along which the element 10 is then destined to be cut in the separation operation performed in the cutting station or cutting unit 112 previously described;

- two intermediate branches 12, each of which is bent on the base branch 11 so as to return towards the line X-X (without reaching it, to prevent unwanted effects of the cut when the closing element 1 is divided in two halves along the plane X-X); And

- two distal branches 14, turned up again on the intermediate branches 12; typically, the distal branches 14 extend with their terminal edges approximately at the outer edges of the base branch 11 and of the loops or elbows which connect the intermediate branches 12 with the edges of the base branch 11.

Naturally, the choice of having the distal portions 14 extend with their end edges approximately in correspondence with the outer edges of the base portion 11 is not to be considered in any way imperative. The distal sections 14 can in fact be made in such a way as to be of equal length, both more â € œshortâ € and more â € œlongâ € with respect to the corresponding portions of the base branch 11. The same is also true in relation to the intermediate sections 12.

The whole strip that constitutes the branches 11, 12 and 14, or at least a portion thereof in correspondence with the branches 14, can be elastically extensible. The manufacture and application of such a resilient material is well known in the sanitation industry.

Reference 16 indicates a layer of glue, intended to fix the intermediate branches 12 (that is to apply them in a stable way) to the homologous parts of the base layer or base branch 11. This preferably takes place by means of further layers 18, preferably in non-material material. tissue. The layers 18 are arranged, again with specular symmetry with respect to the X-X axis, to each form a sort of inner lining which extends around the external surface of the flexed portion between one of the intermediate branches 12 and the distal branch 14 which starts From it.

Extending through each layer 18 along its cusp line, i.e. on the imaginary line separating the intermediate branch 12 and the distal branch 14 extending therefrom, to which layer 18 serves as a lining, is a line of weakening 18a (obtained for example with a line of perforations or a line of material that is easier to tear, for example a thinner material). Each layer 18 can therefore be selectively torn on the weakening line 18a, as detailed below.

Each layer 18 is fixed at its opposite ends:

- to the base branch 11, through an extension of the layer of glue 16, and to the intermediate branch 12, through a layer of glue 20; And

- to the distal layer 14, through a layer / strip of glue 22.

The layers of glue 16, 20 and 22 can for example be hot melt glue or another type commonly used for connecting laminar products, such as in particular non-woven fabrics in the sanitary products industry. .

The reference number 21 indicates temporary sealing formations, which can fix the intermediate branches 12 to the corresponding distal branches 14. These temporary sealing formations can be made with the application of â € œalways greenâ € or â € œpressure points of glue. -sensitiveâ € or through thermo-mechanical welding points (heat sealing).

The reference numbers 23 indicate two openable connection formations, arranged at the ends of the distal branches 14. The openable connection formations 23 are arranged facing outwards of the general omega shape of element 10 and, in the embodiment preferred here, they are made up of reclosable groups of the "micro-hooks" type (or with hooks and loops), of the type commonly known as "Velcro closure". The use of different types of openable connection formations 23 (for example of the adhesive type) which serve the same purpose is however within the scope of the invention.

In a particularly preferred embodiment, if hook and loop formations are used, the `` hooks '' portion 23a is carried (i.e. fixed with adhesive) by the distal branch 14, while the `` loop '' portion 23b is It is intended to be fixed (again for example by means of adhesive at point 25) to the product chain 1, and specifically to the front portions 3 of adjacent products 1 in the chain illustrated in figure 8.

An opposite arrangement (ie with the â € œanseâ € 23b portion carried by the distal branch 14 and the â € œhooksâ € 23a portion fixed to the product 1) is possible. However, the arrangement of the portion of hooks 23a on the distal branch 14 is advantageous in that, at least in some cases, the `` anse '' portion 23b can simply be constituted by the surface of the anterior portion 3 of the product 1, worked in such a way to present the necessary loop structure. Arrangements for providing such a surface with a fabric-like structure having loops are known in the art.

Similarly, reference 26 indicates the possibility of adhesively connecting the base branch 11 to the product chain 1, and specifically to the rear portions 4 of adjacent products 1 in the chain illustrated in Figure 8.

On the basis of the previous description of figure 5, it is easy to understand that the subdivision of the element indicated with 10 as a whole into two components, such as those marked by 10a and 10b in figure 6, is preferably achieved by incorporating the component indicated as 10a all the elements illustrated in Figure 5, with the exception of the hooked portions 23b of the openable formations 23, while the looped portions 23b are incorporated in the component indicated with 10b.

In this case, the action of the pressure rollers 110 essentially comprises the connection and fixing of the hook portions and the loop portions 23b of the openable formations 23.

On the contrary, if a one-piece arrangement is preferred for applying the elements 10, a preferred solution consists in first applying the complete element 10 on the front portions 3 of the products 1, and then making (for example in correspondence with the rollers 110) fixing the base branch 11 to the rear portions 4 of the products 1.

The main advantage of this arrangement consists in the fact that, after being applied on the front portion 3 of the products 1, the element 10 moves with the product chain in a closed and autonomous structure, without free portions that can extend so uncontrolled and â € œflankingâ € from the product as it advances.

To summarize, element 10 comprises two parts which are fundamentally symmetrical with respect to the intermediate plane X-X, each of these parts comprising in turn:

- a base branch 11, which can be connected (at point 26) to the rear end part 4 of the product; And

- a distal branch 14, which can be connected (at point 23) to the frontal extremity part 3.

The base branch 11 and the distal branch 14 are connected to each other according to a general book configuration, which opens towards the outside of the element 10. The dorsal parts of the said book connection configurations between the base branch 11 and the distal branches 14 are arranged at a certain distance from said intermediate plane X-X, so that the two basically symmetrical parts, comprising the element 10, are joined together by means of the base branch 11 so as to form a single body. This single body can be cut in the intermediate plane X-X to separate the two basically symmetrical parts, each of which is able to connect mutually opposite sides of the end parts 3, 4 of a respective absorbent sanitary product 1.

The cross-sectional view of Figure 2 highlights the results of applying the process described with reference to Figure 8, using a closure element 10 of the type illustrated in Figure 5.

Specifically, Figure 2 is a horizontal sectional view through the product 1 worn by a user, with the front portion 3 and the rear portion 4 of the product illustrated in the lower and upper portion of the figure, respectively. Furthermore, only the reference numbers of the fundamental parts of the closing / fixing assembly 10 are reproduced in figure 2.

To facilitate understanding, the arrangement of the parts illustrated for example on the right side of the product 1 illustrated in figure 2 can be considered the one obtained by taking the portion of figure 5 which is on the right side of the X-X axis, and spreading and moving backwards the anterior and posterior portions 3 and 4 of the relative product 1.

Consequently, the two portions 3 and 4 are connected by two elements which extend as a bridge between them.

The first of these elements comprises the layer 18, which has:

- the first end fixed to the rear portion 4 through the adhesive layer 26, the base branch 11 and the adhesive layer 16, and

- the other end fixed to the front portion 3 through the adhesive layer 25.

More specifically, the said first end of the layer 18 is sandwiched between the base branch 11 and the adjacent intermediate branch 12, and is firmly fixed to each other by means of the adhesive layers 16 and 20. The layer 18 thus forms a bond that firmly connects the front and rear portions 3 and 4, to keep the products 1 in the closed condition typical of pre-closed products such as â € œtraining pantâ €. Such a firm bond can be broken, thus opening product 1, tearing the layer at the line of weakening 18a. The force necessary to obtain this result can be adjusted by selecting the characteristics (ie the thickness) of the layer 18 and / or the characteristics (for example the size and number of perforations per unit of length) of the weakening line 18a.

The last bridge elements previously mentioned include the combination of the intermediate and distal branches 12 and 14 of the element 10, and have:

- the first end (essentially formed by the intermediate branch 12) fixed to the rear portion 4 through the adhesive layer 26, the base branch 11 and the adhesive layers 12 and 16, and

- the other end (essentially composed of the distal branch 14) which can be connected in a detachable and repositionable way to the anterior portion 3 through the openable formations 23 (for example with hooks and loops).

In product 1, as initially presented and worn by the user in a closed configuration similar to a panty, the front and rear portions 3 and 4 are therefore firmly connected at the product lifeline 1, by means of both bridge elements previously mentioned.

When the need to open the product 1 emerges (for example to check if the wearer is still clean and dry), the formations 23 are opened by separating the complementary portions 23a and 23b. This result can be obtained by exerting a moderate force, as is the case, for example, with the hook-and-loop fasteners in the shape of a strip that are now widespread in sports shoes.

After the opening of the formations 23, the front and rear portions 3 and 4 are connected only by the layer 18. This can be broken along the line of weakening 18a, thus opening the product 1. This operation can be easily done with one moderate effort, while the tearing of the line of weakening 18a ensures that the two resulting portions of the layer 18, connected to the anterior portion 3 and the posterior portion 4 of the product 1, are separated precisely along the line 18a, essentially in correspondence with the distal margins of the anterior portion 3 and of the posterior portion 4, without the unwanted formation of irregular breaking lines.

After opening the product 1 (for example to check it while it is worn), the product 1 can be closed or fixed again, with the further possibility of adapting the size of the product to the user. This result can be obtained by selectively increasing or decreasing the length of the product lifeline, by selectively varying the position in which the hook element 23a engages the opposite loop element 23b, carried or constituted by the external surface of the anterior portion 3.

In other words, in the illustrated embodiment, the distal branch 14 carrying the element 23a can be fixed on the anterior portion 3 in a plurality of different positions (typically forming a continuum), so that the length of the lifeline of the product 1 is selectively varied.

This is typically done by placing the hook element 23a closer to, or further away from the rear portion 4, depending on the need to increase or decrease the waistline, to give the product a tighter or looser fit around the body. of the user.

The solutions described above lead to the manufacture of a sanitary product in which, among other things:

- the front and rear portions 3, 4 of the product are connected at the lifeline by tab elements which (see in particular figure 2) are completely arranged on the external side of the product, not exposed towards the user's body ; consequently, these connecting / closing elements are absolutely not capable of causing irritation or skin lacerations of the user;

- the preferred reclosability / repositioning feature is obtained by acting on the distal branches 14, i.e. on elements which extend from the rear portion 4 of the product and can be selectively connected (through the hook and loop elements 23) in different positions on the portion front 3;

- the front and rear portions 3, 4 of the product are connected at the lifeline through connecting / closing elements which are totally â € œleveledâ € (i.e. without any noteworthy protrusions) with the external surface of the product (see again figure 2), making sure that the product has a completely similar aspect to the aspect of normal panties;

- the product, as it is distributed to the public, can be folded to small dimensions, as illustrated in figure 10; this allows to obtain a corresponding reduction in the dimensions of the relative package, as exemplified in figures 10 and 12, which is particularly advantageous and appreciated in the case of diapers for incontinence in adults.

Naturally, without prejudice to the principle of the invention, the manufacturing details and the embodiments can vary widely from what has been described and illustrated at the same time, without thereby departing from the scope of the present invention, as defined by the attached claims.

In particular, it will be noted that the implementation details illustrated contextually with reference to each given embodiment are to be interpreted as freely transferable to one or more of the other embodiments illustrated. Furthermore, although the herein preferred embodiments of the invention provide all the structural and functional characteristics previously described with reference to the groups 10, present in both groups currently associated with the product 10, some alternative embodiments of the invention, less preferred, they can provide that these structural and functional characteristics are associated with only one (i.e. with â € œat least oneâ €) of the groups 10. Furthermore, it should be noted that the connection solutions described contextually with reference to adhesive bonding mechanisms can be replaced from equivalent solutions, which foresee, for example, the use of connection mechanisms by means of heat sealing and / or ultrasonic sealing.

For example, the closing groups 10 can be of the permanent type, being that they can be opened only by means of tearing, and not allowing a subsequent closure and possibly repositionability, while maintaining the characteristic of being arranged on the external side of the product 1 and flush with the its external surface, once said product 1 has been returned to its panty configuration, starting from an initial pre-folded C-shaped packaging configuration folded back on itself. For example, with reference to the elements illustrated in Figure 5, a permanent type closure assembly 10 could comprise a distal branch 14 and an intermediate branch 12 arranged symmetrically with respect to the X-X plane and distinct from each other, without being joined by means of a branch base 11. The intermediate branches 12 and the distal branches 14 would be respectively connected to the end parts 4 and 3, with a permanent connection, for example of the adhesive type or by means of heat sealing. Closure groups of this type could be incorporated with routine modifications in a production process such as that illustrated in Figures 4 and 6, leading to the creation of a pre-closed and pre-folded C-shaped sanitary product. same for packaging, having the same functionality described previously in reference to the arrangement of the closing groups on the outside and flush with the surface in the product brought back to the panty configuration by extroversion, but without the feature of reclosability and possibly repositionability.

Naturally, the principle of the invention remaining the same, the details of construction and the embodiments may be widely varied with respect to those described and illustrated without thereby departing from the scope of the invention as defined by the following claims.

Claims (8)

CLAIMS 1. Process for manufacturing a pre-closed hygienic-sanitary article to be worn like a panty, said product (1) comprising two end parts (3, 4) and a crotch portion (2) extending between said end parts (3, 4), in which said two end parts (3, 4) have, on opposite sides of the product (1), pairs of homologous facing side edges connected together by respective closing groups (10) so as to define the lifeline of the product (1), said product (1), said respective end parts (3, 4) and said crotch portion (2) having an external surface and an internal surface, in which the procedure includes the steps of: - manufacturing flat blanks of said products (1), said blanks having an external side with an external surface of the products and comprising two end parts (3, 4) and a crotch portion (2) extending between said two parts end parts (3, 4), in which said end parts (3, 4) have, on opposite sides of the product (1), pairs of homologous side edges facing each other, the process being characterized by the fact that it includes the steps of: - folding (102, 104, 106) said flat blanks of said products (1) into a C-shaped arrangement folded on itself, with said end parts (3, 4) folded along respective fold lines (B) against the internal surface of said fork portion (2), whereby the said two end parts (3, 4) are located one against the other in correspondence with said homologous facing side edges, and - arrange (108, 109) said closing groups (10) sandwiched between the said end parts (3, 4) which are located one against the other near the said homologous facing side edges, so that the said end parts (3, 4) are connected together by respective closing groups (10) so as to define the product lifeline (1), therefore, once the product has been restored to its configuration with the panty with said C-shaped arrangement folded back on itself, said closure groups (10) are arranged on the outer side of the product (1) flush with said outer surface. 2. Process according to claim 1, characterized in that said two end parts (3, 4) have respective topsheet (TS) and backsheet (BS) surfaces, the process comprises the steps of arranging said two end parts ( 3, 4) folded in said C-shaped arrangement folded on itself, with said respective topsheet surfaces partially turned towards the inside of the folded product (1) and said respective backsheet surfaces turned one against the other The other and towards the inside of the folded product (1) and connected by said closing groups (10). 3. Process according to claim 1 or claim 2, characterized in that, in said C-shaped arrangement folded back on itself, said end parts (3, 4) are arranged between said crotch portion (2). 4. Process according to any one of the preceding claims, characterized in that it comprises the step of packaging said folded products (1) in said C-shaped arrangement folded back on itself. 5. Process according to any one of claims 1 to 3, characterized in that it comprises the steps of: - subjecting said products (1) folded in said C-shaped arrangement folded on itself to an extroversion movement, which brings said closing groups (10) on the external side of the products (1), whereby said products ( 1) are returned to a panty package; And - packaging said products (1) brought back to said panty configuration. 6. Pre-closed hygienic-sanitary article to be worn like a panty, pre-folded in the shape of a C folded on itself for packaging, the said product (1) comprising two end parts (3, 4) and a portion of forking (2) extending between said end parts (3, 4), in which said two end parts (3, 4) have, on opposite sides of the product (1), pairs of side edges facing homologous connected together by respective closing groups (10) so as to define the lifeline of the product (1) and the passages for the legs of the user, said product (1), said respective end parts (3, 4) and said crotch portion (2) having an external and an internal side, with respectively an external and an internal surface, wherein said product (1) has said end parts (3, 4) folded along respective fold lines (B) against the internal surface of said crotch portion (2), whereby said end parts (3, 4) they are located one against the other with their respective external surfaces in correspondence with said homologous facing side edges, connected to each other by said respective closing groups (10), therefore, once the product (1) has been returned to its panty configuration from the said pre-folded configuration, the said closing groups (10) are arranged on the external side of the product (1) flush with the said surface external. 7. Article according to claim 6, characterized in that each of said respective closing groups (10) is: - permanently fixed to one of said end parts (3, 4), e - selectively openable and reclosable on the other of said end parts (3, 4). 8. Packaging of pre-closed sanitary articles to be worn as a panty, comprising inside it a plurality of articles according to any one of claims 6 or 7, organized in an ordered stack.