Absorbent article with adhesive patch

Abstract

The present disclosure relates to an absorbent article having a crotch portion and a rear portion, the crotch portion comprising a first front wing and a second front wing extending outwardly from the crotch portion in a transverse direction (x), the aft portion includes a first aft flap and a second aft flap extending outwardly from the aft portion in a lateral direction (x). The first and second front wings each comprise a respective first and second crotch adhesive patch, where each crotch adhesive patch is offset from one another by an offset distance dO in the longitudinal direction (y), and the first and second rear wings each comprise a respective first and second rear adhesive patch, where each crotch adhesive patch is offset from one another by an offset distance dO in the longitudinal direction (y). Wherein the rear adhesive patches are also offset from each other by the same offset distance in the longitudinal direction (y). A method for manufacturing an absorbent article having an offset adhesive patch is also disclosed.

Description

Technical Field

[0001] The present disclosure relates to an absorbent article of the type having a front portion, a rear portion, and a crotch portion disposed between the front portion and the rear portion, the crotch portion having wings extending outwardly from the crotch portion for attaching the article to a user's clothing. Examples of such articles may include incontinence articles, sanitary napkins, panty liners, shields, etc. The present disclosure also relates to a method of making such an article. Background Art

[0002] The general purpose of such absorbent articles is to absorb, distribute and store various types of body exudates while providing a high level of comfort and dryness to the wearer during use of the absorbent article. In addition, such absorbent articles are arranged to prevent the wearer from soiling clothes with body exudates.

[0003] Conventional sanitary napkins are generally designed with a main body, which includes a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent core sandwiched between the top sheet and the back sheet. The main body is arranged along a longitudinal axis and a transverse axis, and the transverse axis extends in a vertical direction relative to the longitudinal axis.

[0004] Furthermore, absorbent articles in the form of sanitary napkins are usually provided with two wings, i.e. two wing-shaped fastening elements, which extend outwardly from the main body in opposite directions and generally along the transverse axis. The purpose of the wings is to allow the sanitary napkin to be fastened to the user's underwear. To this end, the wings are arranged to be folded over the main body and towards the longitudinal axis. In order to allow the sanitary napkin to be fastened to the underwear, each wing is provided with fastening means, such as adhesive material or hook-and-eye type fasteners. In this way, the sanitary napkin can be attached and kept in place in the underwear during use.

[0005] According to the prior art, the wings of the sanitary napkin can be formed in a symmetrical manner, ie such that the entire sanitary napkin can be said to define a symmetrical profile about its longitudinal axis. Alternatively, it is also known that the wings can be formed asymmetrically about the longitudinal axis.

[0006] A previously known absorbent article with asymmetric wings of the above type is known from patent document WO 2019 / 007527. The document shows a sanitary napkin with two wings, which are arranged asymmetrically along opposite sides of the longitudinal edge of the sanitary napkin.

[0007] In some cases, it is desirable to have additional wings or winglets, which can provide additional opportunities for fastening articles to clothing. This is especially true for articles that extend beyond the crotch region of the user and have a considerable forward or backward extension range. In the case of articles to be used at night, additional winglets can be arranged at the rear portion and for being attached to or folded around the buttocks of underwear. This rear winglet or hip winglet can also be fixed with similar devices such as adhesive patches. The example of an absorbent article with both front wing and rear wing is shown in US2004 / 0243087. In this case, adhesive patches are provided on all four wings. Adhesive patches are spaced apart in a rectangular configuration, wherein the left side to patch and the right side to patch are equally spaced apart in the longitudinal direction, and the front patch and the rear patch are equally spaced apart in the transverse direction.

[0008] The manufacture of such articles must of course be highly automated to ensure a cost-effective and consistent product. Conventional production is carried out using continuous webs of topsheet and backsheet material, to which a core is applied to form a precursor web. Adhesive patches are usually applied to a carrier web such as siliconized release paper using a slit coating procedure. They are then applied or transferred to the precursor web, from which a single absorbent article can eventually be cut. The carrier web can be in the form of a single bridging web, carrying adhesive patches for both the left and right flanks. Alternatively, a separate (narrower) carrier web can be provided for the corresponding left and right flanks. This requires less material use.

[0009] For the previous arrangement with four wings, the corresponding adhesive patches have been spaced apart in a rectangular configuration, wherein the left and right pairs of patches are all located at the same corresponding longitudinal position and are equally spaced apart in the longitudinal direction, and in addition, the front and rear patches are equally spaced apart in the transverse direction. This configuration is considered to be important for the smooth operation of the production process. For a single bridging web, the positions of the adhesive patches are fixed relative to each other and can only be adjusted by changing the slit coating procedure. Generally, it is preferred to have only one left slit applicator and one right slit applicator, so the front and rear patches must be aligned. In addition, if a separate left carrier web and a right carrier web are used, the front and rear patches must also be aligned, i.e., spaced equidistantly from the longitudinal axis. However, even if a separate left carrier web and a right carrier web are used, it is still desirable and important that the two webs are mounted on a common axis to ensure that timing accuracy is achieved. Then, this means that the two carrier webs will travel at the same speed, which determines that the spacing between the front and rear patches for the corresponding left and right sides in the longitudinal direction will be the same.

[0010] While the fixed rectangular configuration described above is generally acceptable for many absorbent articles, it is not adequately suited for articles that require some asymmetry.Therefore, there is a need for further improvements in articles and processes. Summary of the invention

[0011] According to the present invention, a kind of absorbent article is disclosed, it has a crotch portion and a rear portion, wherein the crotch portion includes the first front wing and the second front wing extending outward from the crotch portion in a transverse direction (x), and the rear portion includes the first rear wing and the second rear wing extending outward from the rear portion in a transverse direction (x). The first front wing and the second front wing each include a corresponding first crotch adhesive patch and a second crotch adhesive patch, wherein the crotch adhesive patch is offset from each other by an offset distance dO in a longitudinal direction (y), and the first rear wing and the second rear wing each include a corresponding first rear adhesive patch and a second rear adhesive patch, wherein the rear adhesive patch is also offset from each other by the same offset distance in a longitudinal direction (y). In this article, the rear wing is referred to as a wing, so as to distinguish them from the wing located in the crotch portion. However, it should be understood that the terms "wing" and "wing" can be used interchangeably. In addition, reference is made to the first and second front wings located on the corresponding left and right sides of the article. With reference to their positions relative to the user's body when in use, these can also be referred to as left and right wings, respectively. The same nomenclature may be used for example for the first and second rear flaps and other parts of the article.

[0012] Absorbent article can be any suitable article intended to be fixed in clothes for absorption purposes. This can include incontinence articles, sanitary napkins, panty liners, shielding pieces, etc. The article can have other conventional structures. Usually, this article includes a liquid-permeable top sheet, a liquid-impermeable back sheet, an absorbent core arranged between the top sheet and the back sheet, and it has a central transverse axis (X) and a central longitudinal axis (Y). The resulting absorbent article includes a front portion, a rear portion, and a crotch portion arranged between the front portion and the rear portion, wherein the length of the absorbent article in the longitudinal direction (y) is limited to the central longitudinal axis between the front edge of the front portion and the rear edge of the rear portion. In an embodiment, the length of the article in the longitudinal direction can be in the range of 150mm to 400mm, preferably 280mm to 327mm. In addition, the front portion and the crotch portion can each include 30% of the total length of the absorbent article in the longitudinal direction (y), and the rear portion can include 40% of the total length.

[0013] Because the offset distance is equal, the repeat distance (dA) between the first crotch adhesive patch and the first rear adhesive patch in the longitudinal direction (y) is equal to the repeat distance (dB) between the second crotch adhesive patch and the second rear adhesive patch in the longitudinal direction (y). About this, the repeat distance is measured from the leading edge of the corresponding adhesive patch. Should be understood that if two patches are of the same size, then no matter where to measure the repeat distance is all the same. By ensuring that the left and right patches all have the same spacing, the placement of adhesive patches during the manufacturing stage can be simplified. This is applicable to left patches and right patches being applied to the common carrier web, and also applicable to the situation that independent left carrier web and right carrier web are used, are installed to common roller or shaft.

[0014] As a result of the offset between the first and second crotch adhesive patches, a greater length of bonding is achieved in the crotch region, because from front to back, the absorbent article is first attached to the left side, then to the right side (or vice versa). The offset between the patches can also help ensure that when folding wings or winglets, the adhesive patches can not be attached to each other. For the offset back patch, due to the asymmetric placement of the back patch relative to the underwear surface, other advantages can also be present. It should be understood that, except for the adhesive patches positioned on the wings and winglets, additional adhesive areas or patches can be provided elsewhere on the back sheet for being connected to underwear.

[0015] The repeat distance will depend on the individual size and shape of the absorbent article.In certain embodiments, the distance (dA, dB) is in the range of 100 mm to 250 mm, preferably 140 mm to 200 mm.

[0016] The offset distance will also depend on the individual size and shape of the absorbent article. In certain embodiments, the offset distance dO is in the range of 10 mm to 40 mm, preferably between 15 mm to 30 mm, more preferably about 20 mm.

[0017] The absorbent article can have any suitable outer contour, which is symmetrical around the longitudinal axis or the transverse axis, or symmetrical around both, or asymmetrical. The present invention is particularly suitable for asymmetric articles, especially articles with asymmetry about the longitudinal axis. In this way, the offset between the left and right adhesive patches can be used to better align the asymmetry of the outer contour. In one embodiment, the first front wing and the second front wing extend outwardly from the crotch portion in an asymmetric manner about the central longitudinal axis (Y). This means that the first front wing and the second front wing are also offset relative to each other along this axis, that is, the first front wing can be positioned more forward (or vice versa) than the second front wing. Each wing can also be asymmetric about the central transverse axis (X).

[0018] In addition, the first rear wing and the second rear wing can have any suitable shape, and can be symmetrical or asymmetrical.In a particular embodiment, the first rear wing and the second rear wing are symmetrical about the central longitudinal axis (Y), and the first forewing and the second forewing are asymmetrical.In other words, the distance between the left forewing and the rear wing will be different from the distance between the right forewing and the rear wing.This causes the overall construction of article, whereby all adhesive patches and forewing are offset at the corresponding left and right sides of article, and the rear wing is not offset.Therefore, the rear adhesive patch will be located at different relative positions on the corresponding rear wing.Because the area of ​​the rear wing is usually larger than forewing, there are more areas where the rear adhesive patch can be acceptably attached thereto, and the edge of the article will not be approached.Therefore, even if the rear wing is not offset, it is also possible to realize the manufacturing benefit of having equal offset between the corresponding left adhesive patch and the right adhesive patch.

[0019] Should be understood that the offset between the left and right adhesive patches can be different from the offset between the left and right front wings.Therefore, the front adhesive patches can also be located at different relative positions on the corresponding front wings.

[0020] As mentioned above, absorbent article can have any suitable structure that is conventionally applicable to such article.In one embodiment, the extension range of absorbent core in the plane of longitudinal axis and transverse axis is smaller than the extension range of backsheet and / or topsheet.Then, the body-facing surface of backsheet can be preferably joined to the surface facing clothes of topsheet at the periphery.In one embodiment, topsheet can have substantially the same extension range in the plane of longitudinal extension and transverse extension of absorbent article, and the marginal area of ​​absorbent article is joined together.But, do not exclude that backsheet may have larger extension range than topsheet, and vice versa.

[0021] According to selected materials, top sheet and back sheet can be joined by conventional means. Particularly, they can be joined by adhesive, heat sealing, embossing and / or ultrasonic treatment.

[0022] The absorbent article may further comprise a liquid acquisition sheet arranged between the top sheet and the absorbent core. Such acquisition layers are generally known and may be particularly suitable for quickly receiving and temporarily storing discharged liquid before the discharged liquid is absorbed by the absorbent core.

[0023] According to the present disclosure, the adhesive patch can be of any suitable type, suitable for being releasably attached to the user's clothing without damaging or otherwise marking the intended function of the clothing. The term "adhesion" is not intended to be limited to glue, but may also include other adhesive materials, such as hook-shaped micro-fasteners. Preferred adhesive materials are those that can be applied as coatings using slit coaters currently installed in existing production lines. These include pressure-sensitive adhesives, which include cold-pressed adhesives. The adhesive patch may also be deposited by any other suitable means, including spray application, delivery nozzles, transfers, etc.

[0024] Depending on the application method, the adhesive patch can have any specific form. In one embodiment, the crotch adhesive patch and the rear adhesive patch are roughly rectangular in shape. This can be the external shape of the patch, which itself can be composed of a separate adhesive point or a thin strip of adhesive. In particular, the length of the crotch adhesive patch in the longitudinal direction (y) is in the range of 10 to 50 mm, preferably in the range of 30 to 46 mm, and the width in the transverse direction (x) is in the range of 4 to 20 mm, preferably in the range of 8 to 15 mm.

[0025] The length of the rear adhesive patch in the longitudinal direction (y) may be in the range of 10 to 50 mm, preferably in the range of 20 to 30 mm, and the width in the transverse direction (x) may be in the range of 4 to 20 mm, preferably in the range of 8 to 15 mm. In one embodiment, the length of the crotch adhesive patch in the longitudinal direction (y) may be greater than the length of the rear adhesive patch in the longitudinal direction (y). Then, the shorter rear adhesive patch can better fit in the area of ​​the rear wing, despite their offset.

[0026] Crotch adhesive patch and rear adhesive patch can be arranged substantially parallel to the central longitudinal axis (Y). This is usually the case when applying adhesive patches using slit coating technology in a process where the machine direction is aligned with the longitudinal axis. In addition, the adhesive patches can each be spaced apart from the central longitudinal axis (Y) by a spacing distance, and the spacing distance d1 of the first crotch adhesive patch is equal to the spacing distance d2 of the first rear adhesive patch, and the spacing distance d3 of the second crotch adhesive patch is equal to the spacing distance d4 of the second rear adhesive patch. By aligning the front adhesive patch and the rear adhesive patch, a relatively narrow carrier width can be used for each of the corresponding left and right groups of adhesive patches, and a single slit coater can be used.

[0027] In some embodiments, the spacing distances d1 and d2 may be different from the spacing distances d3 and d4. In other words, the left adhesive patch and the right adhesive patch may not be positioned at the same lateral position on the article. This may be preferred or necessary in order to optimally position the adhesive patch relative to the corresponding wing.

[0028] The first and second back wings may also have any suitable size and shape depending on the intended user and garment. The wings extend outwardly from the central longitudinal axis (Y) in the transverse direction by a distance dF, and the first front wing and the second front wing extend outwardly by a distance dW. In a preferred embodiment, dF is equal to or greater than dW.

[0029] The position of all adhesive patches is preferably sufficient distance from the edge of the absorbent article. It is usually not desirable to place the adhesive patch outside the outline of the article during the manufacturing process, even if tolerance is allowed. According to some manufacturing methods, the outer contour can be cut, including any outwardly extending part of the adhesive patch. However, it may not be desirable to make the cutting edge of the adhesive patch coincide with the edge of the article, because this may be lifted or peeled off during use. Preferably, the minimum distance between any adhesive patch and the outer contour of the absorbent article is 5mm, preferably 10mm.

[0030] As mentioned above, each adhesive patch can be applied using a carrier web. Preferably, the carrier web is in the form of a release material, such as siliconized paper, which is retained on the adhesive patch as a release cover when manufacturing is complete. A single release cover can cover all adhesive patches. Alternatively, left and right release covers can cover corresponding left and right adhesive patches. More preferably, an independent release cover can be present on each adhesive patch.

[0031] The rear wing can extend outward laterally, but can also extend backward. In one embodiment, this causes the rear edge of the absorbent article to have an incision between the corresponding last extension of the first rear wing and the left rear wing. The incision can have an arcuate shape extending between the first rear wing and the second rear wing. In one embodiment, the rear incision has a maximum depth (dR) in the range of 10mm to 20mm, preferably 12mm to 15mm relative to the line (XR) of the last point of the first rear wing and the second rear wing. Additionally or alternatively, the rear incision has the shape of a shallow isosceles triangle, forming an angle in the range of 18 to 30 degrees, preferably 20 to 22 degrees, relative to the central longitudinal axis (Y). The presence of the incision can be conducive to removing excess material between the buttocks area. This can improve comfort during use and increase the flexibility of the product towards the user's body. In addition, if the shape of the incision matches the front edge of the front part in shape, the effective cutting out of the absorbent article can be allowed.

[0032] The present invention also relates to a method of manufacturing an absorbent article, comprising:

[0033] conveying a continuous front body web in a longitudinal direction, the continuous front body web comprising at least a backsheet and an absorbent core and having left and right lateral edges;

[0034] providing a continuous carrier web structure;

[0035] repeatedly applying the front and rear adhesive patches to respective left and right sides of the carrier web structure, wherein the left front adhesive patch is offset in the longitudinal direction from the right front adhesive patch, and the left rear adhesive patch is offset in the longitudinal direction from the right rear adhesive patch;

[0036] bonding the carrier web structure and the precursor web together to attach the adhesive patch to the precursor web; and

[0037] Individual absorbent articles are cut from the front body web, the individual articles having wings, and wherein the adhesive patches are located on the wings.The absorbent article may be an article as defined above or below.

[0038] In some embodiments, the carrier web structure includes a left carrier web and a right carrier web, and the left front adhesive patch and the left rear adhesive patch are arranged on the left carrier web, and the right front adhesive patch and the right rear adhesive patch are arranged on the right carrier web. This allows less material to be used because the carrier web can be limited to the corresponding width of the adhesive patch.

[0039] In a particular embodiment, the carrier web is a release paper, and the method comprises cutting the carrier web into individual release papers, each carrying a corresponding adhesive patch, before attaching the patch to the precursor web. The cutting can be performed in a conventional manner, for example by rotating a knife against a transport roller, whereby the transport roller is also used to attach the adhesive patches together with their respective individual release papers to corresponding locations on the precursor web.

[0040] In one embodiment, the distance between successive adhesive patches is constant. This means not only that the distance between the front adhesive patch and the rear adhesive patch is the same for the left and right sides, but also that it is the same as the distance between the rear adhesive patch on the first absorbent article and the front adhesive patch on the subsequent article. This arrangement simplifies the synchronization between the adhesive applicator and the conveying device for the corresponding width. This is particularly desirable for the situation where the adhesive patch is applied by the slit coating of the liquid adhesive material.

[0041] Cutting out individual absorbent articles from the front body web may be done with or without loss of material between the front and rear edges of adjacent articles. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The features and advantages of the present disclosure will be understood by referring to the following drawings of various exemplary embodiments, in which:

[0043] Figure 1A A plan view of a sanitary napkin according to one embodiment of the present invention is shown;

[0044] Figure 1B Shows Figure 1A A plan view of a sanitary napkin showing certain dimensions;

[0045] Figure 2 A cross-sectional view taken at the central transverse axis X is shown. Figure 1A A cross-section of a sanitary napkin; and

[0046] Figure 3 A schematic diagram of a machine for manufacturing absorbent articles according to the invention is shown. DETAILED DESCRIPTION

[0047] Various aspects of the present disclosure will be described more fully below with reference to the accompanying drawings. However, the embodiments disclosed herein may be implemented in many different forms and should not be construed as limited to the aspects set forth herein.

[0048] First reference Figure 1A , shows a plan view on the top sheet of an absorbent article in the form of a sanitary napkin 1 made according to one embodiment of the present invention. The sanitary napkin 1 is based on an absorbent structure for absorbing body exudates from the wearer so as to provide the wearer with a feeling of dryness, comfort and odorlessness.

[0049] from Figure 1A As will be appreciated, sanitary towel 1 comprises a main body 2 with a top sheet 3 permeable to liquid and a back sheet 4 impermeable to liquid. Sanitary towel 1 also comprises an absorbent core 5 sandwiched between top sheet 3 and back sheet 4. Top sheet 3 is arranged on the surface of sanitary towel 1, i.e., on a side facing the wearer. Back sheet 4 is arranged on the downside of sanitary towel 1, i.e., on a side facing the wearer's underwear (not shown). In addition, top sheet 3 and back sheet 4 all extend laterally along the entire periphery 20 of main body 2 outside the absorbent core 5.

[0050] In the illustrated embodiment, the acquisition layer 13 is arranged between the absorbent core 5 and the top sheet 3. The acquisition layer 13 can be, for example, in the form of an air-laid layer, a spunlace layer, a high loft, a foam or any other type of material layer that can be used in absorbent articles to act as a liquid acquisition and absorption layer. The acquisition layer 13 is suitable for quickly receiving and temporarily storing the discharged liquid before the discharged liquid is absorbed by the absorbent core 5. Such an acquisition layer 13 can be composed of, for example, an air-laid nonwoven, a spunlace nonwoven, a high loft nonwoven or a foam material. Air-laid nonwovens can be produced with fluff, wood pulp, and here, the fluff fibers are dispersed into a fast-moving airflow and condensed onto a moving screen by means of pressure and vacuum. The web can be bonded with a resin and / or a thermoplastic resin dispersed in the pulp. The web can be thermally bonded (by heat), latex-bonded (by adhesive) or multi-bonded (a combination of thermal bonding and latex bonding) or mechanically bonded (high compression and high temperature, bonded by hydrogen bonding). The grammage of the airlaid nonwoven may be, for example, 50-100 gsm.

[0051] Top sheet 3, back sheet 4 and absorbent core 5 can be made of any material suitable for its specific purpose, as will be discussed in further detail below.In addition, above-mentioned layer 3,4,5 can be connected to each other by any conventional means, for example by adhesive, thermal bonding or ultrasonic bonding.

[0052] Furthermore, although not shown in the drawings, the sanitary napkin 1 may be constructed in such a way as to have different material layers, densities or material compositions as viewed along a horizontal plane of the sanitary napkin 1 , ie in addition to being constructed with different layers in a vertical direction.

[0053] like Figure 1A As shown, the sanitary napkin 1 can be divided into a front portion 6, a rear portion 7 and a crotch portion 8. The front portion 6 is intended to be oriented in the direction of the abdomen of the wearer during use of the sanitary napkin 1. In addition, the sanitary napkin 1 has a longitudinal extension along the central longitudinal axis Y in the longitudinal direction Y from a front edge 21 in the front portion 6 to a rear edge 22 in the rear portion 7. It also has a transverse extension along the central transverse axis X in the transverse direction X between the left edge 23 and the right edge 24.

[0054] In addition, according to an embodiment, the sanitary napkin 1 is formed with two front wings 9A, 9B, which are configured to fasten the sanitary napkin 1 to the underwear of the wearer. More specifically, the sanitary napkin 1 includes a first front wing 9A and a second front wing 9B, each of which extends outward from the main body 2 in opposite directions. The wings 9A, 9B extend generally in the direction of the transverse axis X. In addition, the wings 9A, 9B are provided with crotch adhesive patches 11A, 11B, which are configured to fasten the wings 9A, 9B to the underwear when the wings 9A, 9B are folded under the main body 2 in the direction toward the longitudinal axis Y. It should be noted that the crotch adhesive patches 11A, 11B are arranged on the lower side of the sanitary napkin 1, connected to the base 4 and only shown in shadow.

[0055] like Figure 1A As shown, the two wings 9A, 9B are arranged in an asymmetrical manner about the longitudinal axis Y. Both wings are located in the crotch portion 8, but the first front wing 9A is closer to the front portion 6 and the second front wing 9B is closer to the rear portion 9B. Such wings and their advantages are described, for example, in WO2019 / 008091, the content of which is fully incorporated herein.

[0056] The sanitary napkin 1 is also provided with two rear wings 10A, 10B, which can also be fastened to the wearer's underwear. These include a first rear wing 10A and a second rear wing 10B. The rear wings 10A, 10B extend outwardly and rearwardly from the main body 2. The wings 10A, 10B are provided with rear adhesive patches 12A, 12B also located on the backsheet 4 side of the sanitary napkin 1.

[0057] Crotch adhesive patch 11A, 11B and rear adhesive patch 12A, 12B are located on their respective wings 9A, 9B and wing 10A, 10B at positions that ensure that they are spaced apart from periphery 20. In particular, adhesive patches are spaced apart from central longitudinal axis (Y) by a spacing distance d. The first crotch adhesive patch 11A is at a spacing distance d1. The first rear adhesive patch 12A is at a spacing distance d2. The second crotch adhesive patch is located at a spacing distance d3, and the second rear adhesive patch 12B is located at a spacing distance d4. In the illustrated embodiment, the first crotch adhesive patch 11A and the first rear adhesive patch 12A are aligned in the longitudinal direction x, wherein d1 equals d2 and d3 equals d4. In addition, in the illustrated embodiment, d1 equals d3, so it will be understood that all adhesive patches are equally spaced apart from central longitudinal axis Y.

[0058] Figure 1B is with Figure 1A 1. The view of similar sanitary napkin 1, and for more clearly illustrating the corresponding size and position of some articles. It can be seen that the first crotch adhesive patch 11A and the second crotch adhesive patch 11B are offset relative to each other. The first crotch adhesive patch 11A is positioned to be more offset distance d0 towards the front edge 21 than the second crotch adhesive patch 11B. It should be noted that the offset distance d0 ensures that the first crotch adhesive patch 11A falls in the first front wing 9A, and the second crotch adhesive patch 11B falls in the second front wing 9B. The first crotch adhesive patch 11A and the second crotch adhesive patch 11B are both separated by a minimum spacing dM from the periphery 20.

[0059] The first rear adhesive patch 12A and the second rear adhesive patch 12B are also offset relative to each other by the same offset distance dO, whereby the second rear adhesive patch 12B is closer to the rear edge 22. In this case, it should be noted that the rear flaps 10A, 10B are symmetrical about the longitudinal axis Y. However, the area of ​​the rear flaps 10A, 10B is sufficient so that the rear adhesive patches 12A, 12B can be positioned without being close to the perimeter 20, but rather spaced at least the minimum spacing dM from the perimeter.

[0060] Between the rear flaps 10A, 10B, the rear edge 22 is provided with a cutout 30 having an arcuate shape. The cutout 30 corresponds generally to the shape of the front edge 21, as will be explained further below. The rear cutout 30 has a maximum depth dR relative to a baseline XR joining the rearmost points of the first rear flap 10A and the second rear flap 10B. The rear cutout 30 generally has the shape of a shallow isosceles triangle, forming an angle α of approximately 20 degrees relative to the central longitudinal axis (Y).

[0061] Figure 2is a cross-sectional view looking forward at the transverse axis X shown in Figure 1. The absorbent core 5 is sandwiched between the top sheet 3 and the back sheet 4. As mentioned above, the acquisition layer 13 is arranged between the absorbent core 5 and the top sheet 3. Furthermore, two wings 9A, 9B are shown, which are provided with adhesive patches 11A, 11B applied on their underside, i.e. on the side not facing the wearer.

[0062] exist Figure 1A , 1B Not visible in but in Figure 2 , the adhesive patches 11A, 11B are covered with release paper layers 19A, 19B which are present when the sanitary napkin 1 is in its unused state. When the sanitary napkin 1 is to be used, the user removes the release paper layers 19A, 19B so that the sanitary napkin 1 can be fastened to underwear.

[0063] The nature and design of the various layers and components forming part of the sanitary napkin 1 will now be described in more detail with reference primarily to FIGS. 1 and 2 .

[0064] According to one embodiment, the top sheet 3 is formed by a fluid permeable nonwoven fabric or film made of thermoplastic synthetic fibers. The top sheet 3 is sufficiently liquid permeable to allow discharged body fluids to penetrate the thickness of the top sheet 3. In addition, the top sheet 3 is suitably made of a material that is compliant and feels soft to the wearer's skin.

[0065] According to different embodiments, the top sheet 3 can be made of various web materials, such as nonwoven films, foams or combinations of the above materials. The top sheet 3 can also be perforated.

[0066] In addition, backsheet 4 is made of a liquid-impermeable and breathable layer, such as a polymer film, such as a polyethylene or polypropylene film. According to different embodiments, the material that can be used for backsheet 4 includes a thin and flexible fluid-impermeable plastic film or a fluid-impermeable nonwoven material, a fluid-impermeable foam and a fluid-impermeable laminate.

[0067] According to the embodiment shown in the drawings, the backsheet 4 is formed by a single layer, but may alternatively be formed by a multilayer structure (i.e. a laminate), at least one of which is fluid-impermeable. In addition, the backsheet 4 may optionally be elastic in any direction. In addition, backsheet materials that are not completely liquid-impermeable but only resistant to fluid penetration may also be used, particularly in the case where the sanitary napkin 1 is expected to absorb relatively small amounts of body exudates.

[0068] According to further embodiments, the backsheet 4 may be breathable, which means that air and vapor can pass through the backsheet 4. Furthermore, the backsheet 4 may optionally have a garment-facing outer surface of a textile material, such as a nonwoven material.

[0069] The absorbent core 5 may be formed from one or more layers of fibers comprising cellulose fluff pulp. According to alternative embodiments, the absorbent core 5 may be made of any suitable absorbent or fluid-absorbent material known in the art, such as foams, fiberfills and similar materials. As mentioned above, different types of material layers, such as airlaid, hydroentangled and high-loft materials, may be used alone or in combination, depending on the desired properties and field of use of the sanitary napkin 1 in question.

[0070] According to one embodiment, the absorbent article 1 is a liner, in which case the absorbent core 5 may be made of only one thin material, such as a nonwoven layer.

[0071] According to another embodiment, the absorbent core 5 comprises a suitable amount of superabsorbent particles. Such superabsorbent materials are well known in the field of absorbent articles and consist of water-swellable and water-insoluble materials that are able to absorb large amounts of fluid when forming a hydrogel. Normal superabsorbent materials are able to absorb at least 10 times their own weight of fluid. According to one embodiment, the amount of superabsorbent particles is at least 10% by weight, i.e. relative to the total weight of the absorbent core 5.

[0072] Superabsorbent is mixed into the material of the absorbent core 5. The absorbent core 5 may also contain components for improving the properties of the absorbent core 5. Some examples of such components are binder fibers, fluid dispersion materials, fluid acquisition materials, etc., as known in the art. According to one embodiment, the mixture of cellulosic fluff pulp and superabsorbent is mixed throughout the absorbent core 5 in a generally uniform manner.

[0073] According to other embodiments, the absorbent core 5 can be a homogeneous structure, or can be a layered structure with laminates of the same or different materials. Each absorbent layer can have a uniform thickness, or the thickness can be varied in different parts of the layer. Moreover, the basis weight and components of the absorbent core 1 can vary within such an absorbent layer.

[0074] Furthermore, as known to a person skilled in the art, the various layers of the sanitary napkin 1 may be suitably attached by means of layers of adhesive material. These adhesive layers are not shown in the drawings.

[0075] About adhesive patch 11A, B and 12A, B, the adhesive material used can be any one of a large amount of commercially available pressure-sensitive adhesives, including cold pressure-sensitive adhesives, such as acrylate adhesives, usually combined with tackifiers such as polyterpenes (polyterpenes), or fast-setting thermoplastic adhesives (or hot melt adhesives) such as styrene and butadiene copolymers. Other ingredients can be included, such as fillers, antioxidants and pigments. Adhesive patch can also include double-sided tape or another type of adhesive. Adhesive can be applied to the negative film with various patterns, such as spots, squares, single complete or discontinuous lines or multiple complete or discontinuous lines, which can be parallel or non-parallel. Other patterns are also possible. Suitably, pressure-sensitive adhesive is a pressure-sensitive hot melt adhesive. As will be further described below, adhesive can be sprayed or slit-coated to the surface facing clothes of the negative film in corresponding wings or wing regions, or is first applied to release paper layer 19A, 19B.

[0076] Figure 3 is a schematic diagram of a machine 100 for manufacturing an absorbent article according to the present invention, such as the sanitary napkin 1 described in Figures 1 and 2 above.

[0077] The machine 100 comprises a main conveying path 102 which delivers a precursor web 104 in a process direction y corresponding to the longitudinal direction of the sanitary napkin 1. The precursor web 104 comprises a topsheet 3 and a backsheet 4, wherein a core 5 and an acquisition layer 13 are preassembled together. The assembly of these elements is generally conventional and is not further described as it does not form part of the present invention.

[0078] The machine 100 also has left and right carrier rollers 108A and 108B, which deliver left and right carrier webs 112A and 112B of release paper to a slot coating station 114. The delivery speed is controlled by left and right feed rollers 113A and 113B mounted to rotate on a common shaft 110. At the slot coating station 114, left and right slot coating nozzles 115A and 115B deliver adhesive material to the left and right carrier webs 112A and 112B. The left and right slot coating nozzles 115A and 115B are arranged to deliver adhesive material in an offset manner, so that the adhesive material is delivered to the left carrier web 112A before the right carrier web 112B as offset adhesive patches 11A, 11B and 12A, 12B. The left and right carrier webs 112A, 112B are advanced to a delivery roller 118 where they are cut by a rotary cutter 120 into individual release paper layers 19A, 19B, each carrying a respective adhesive patch 11A, 11B. The delivery roller 118 is a conventional vacuum roller which, once the release paper layers 19A, 19B have been cut, retains the release paper layers 19A, 19B on its surface by suction. It also serves as an anvil against which the rotary cutter 120 can cut.

[0079] On further rotation, the transport rollers 118 engage the adhesive patches 11A, 11B with the front body web 104, whereby the alignment means ensure that the adhesive patches 11A, 11B are correctly aligned with the areas of the front body web 104 designated to become the front wings 9A, 9B.

[0080] Subsequently, the front body web 104 passes through a vacuum cylinder 124 which engages with an outer contour cutter 122 to cut around the periphery 20 of the main body 2 to form the sanitary napkin 1 .

[0081] Thus, the present disclosure has been described by reference to the embodiments discussed above. It should be appreciated that these embodiments are susceptible to various modifications and alternative forms well known to those skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims

1. An absorbent article, comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, an absorbent core arranged between the top sheet and the back sheet, a central transverse axis (X) and a central longitudinal axis (Y), wherein the absorbent article comprises a front portion, a rear portion and a crotch portion arranged between the front portion and the rear portion, and the length of the absorbent article in the longitudinal direction (y) is limited between the front edge of the front portion and the rear edge of the rear portion at the central longitudinal axis, the crotch portion comprises a first front wing and a second front wing extending outwardly from the crotch portion in the transverse direction (x), the rear portion comprises a first rear wing piece and a second rear wing piece extending outwardly from the rear portion in the transverse direction (x), characterized in that The first front wing and the second front wing each include a corresponding first and second crotch adhesive patch, wherein the crotch adhesive patches are offset from each other by an offset distance dO in the longitudinal direction (y), and the first back wing and the second back wing each include a corresponding first and second back adhesive patch, wherein the back adhesive patches are also offset from each other by the same offset distance in the longitudinal direction (y).

2. The absorbent article according to claim 1, wherein the repetition distance (dR) between the first crotch adhesive patch and the first rear adhesive patch and between the second crotch adhesive patch and the second rear adhesive patch in the longitudinal direction (y) is in the range of 100 mm to 250 mm, preferably in the range of 140 mm to 200 mm.

3. The absorbent article according to any one of the preceding claims, wherein the offset distance (dO) is in the range of 10 mm to 40 mm, preferably between 15 mm and 30 mm, more preferably about 20 mm.

4. An absorbent article according to any one of the preceding claims, wherein the first front wing and the second front wing extend outwardly from the crotch portion in an asymmetrical manner about the central longitudinal axis (Y) and preferably also about the central transverse axis (X).

5. The absorbent article according to any one of the preceding claims, wherein the first and second rear flaps are symmetrical about the central longitudinal axis (Y).

6. An absorbent article according to any one of the preceding claims, wherein the absorbent core extends less in the plane of the longitudinal axis and the transverse axis than the back sheet and / or the top sheet, the body-facing surface of the back sheet preferably being joined to the garment-facing surface of the top sheet at the periphery.

7. An absorbent article according to any one of the preceding claims, wherein the back sheet and the top sheet have substantially the same extension in planes extending longitudinally and transversely of the absorbent article, and the edge areas of the absorbent article are joined together by embossing and / or ultrasonic treatment.

8. An absorbent article according to any one of the preceding claims, wherein the crotch adhesive patch and the rear adhesive patch are generally rectangular in shape.

9. An absorbent article according to any one of the preceding claims, wherein the length of the crotch adhesive patch in the longitudinal direction (y) is greater than the length of the rear adhesive patch in the longitudinal direction (y), preferably in the range of 10 to 50 mm, preferably in the range of 30 to 46 mm, and the width in the transverse direction (x) is in the range of 4 to 20 mm, preferably in the range of 8 to 15 mm.

10. An absorbent article according to any one of the preceding claims, wherein the length of the rear adhesive patch in the longitudinal direction (y) is in the range of 10 to 50 mm, preferably in the range of 20 to 30 mm, and the width in the transverse direction (x) is in the range of 4 to 20 mm, preferably in the range of 8 to 15 mm.

11. The absorbent article according to any one of the preceding claims, wherein the crotch adhesive patch and the rear adhesive patch are arranged substantially parallel to the central longitudinal axis (Y).

12. An absorbent article according to any one of the preceding claims, wherein the adhesive patches are each spaced apart from the central longitudinal axis (Y) by a spacing distance d, and the spacing distance d1 of the first crotch adhesive patch is equal to the spacing distance d2 of the first rear adhesive patch, and the spacing distance d3 of the second crotch adhesive patch is equal to the spacing distance d4 of the second rear adhesive patch.

13. The absorbent article according to claim 12, wherein the interval distances d1 and d2 are different from the interval distances d3 and d4.

14. An absorbent article according to any one of the preceding claims, wherein the first rear wing and the second rear wing extend outwardly from the central longitudinal axis (Y) in the transverse direction by a distance dF, and the first front wing and the second front wing extend outwardly from the central transverse axis (Y) by a distance dW, and dF is equal to or greater than dW.

15. An absorbent article according to any one of the preceding claims, wherein the minimum distance between the adhesive patch and the outer contour of the absorbent article is 5 mm, preferably 10 mm.

16. An absorbent article according to any one of the preceding claims, wherein each said adhesive patch is provided with a respective release cover.

17. An absorbent article according to any one of the preceding claims, wherein the length in the longitudinal direction is in the range of 150 mm to 400 mm, preferably 280 mm to 320 mm.

18. The absorbent article according to any one of the preceding claims, further comprising a liquid acquisition sheet disposed between the topsheet and the absorbent core.

19. The absorbent article according to any one of the preceding claims, wherein the rear edge is provided with a cutout having an arcuate shape between the first and second rear flaps.

20. The absorbent article according to any of the preceding claims, wherein the front portion and the crotch portion each comprise 30% of the total length of the absorbent article in the longitudinal direction (y), and the rear portion comprises 40% of the total length.

21. A method of making an absorbent article, comprising: conveying a continuous front body web in a longitudinal direction, the continuous front body web comprising at least a backsheet and an absorbent core and having left and right lateral edges; providing a continuous carrier web structure; repeatedly applying front and rear adhesive patches to respective left and right sides of the carrier web structure, wherein the left front adhesive patch is offset from the right front adhesive patch in the longitudinal direction, and the left rear adhesive patch is offset from the right rear adhesive patch in the longitudinal direction; bringing the carrier web structure and the precursor web together to attach the adhesive patch to the precursor web; and Individual absorbent articles are cut from the front body web, the individual articles having wings, and wherein the adhesive patches are located on the wings.

22. The method according to claim 21, wherein the carrier web structure comprises a left carrier web and a right carrier web, and the left front adhesive patch and the left rear adhesive patch are arranged on the left carrier web, and the right front adhesive patch and the right rear adhesive patch are arranged on the right carrier web.

23. A method according to claim 21 or claim 22, wherein the carrier web is a release paper and the method comprises cutting the carrier web into individual release papers, each carrying a respective adhesive patch, before attaching the patch to the precursor web.

24. A method according to any one of claims 21 to 23, wherein the distance between consecutive adhesive patches is constant.

25. A method according to any one of claims 21 to 24, wherein the adhesive patch is applied by slot coating of a liquid adhesive material.

26. The method according to any one of claims 21 to 25, wherein the absorbent article is an article according to any one of claims 1 to 20.

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