Patent Application
20220192898
The disclosure relates to an absorbent article comprising a liquid-permeable topsheet, a liquid impermeable backsheet and an absorbent core positioned intermediate the liquid permeable topsheet and the liquid impermeable backsheet.
Wearable and disposable absorbent articles, for example in the form of diapers, incontinence articles and feminine hygiene pads offer the benefit of receiving and containing urine, feces and/or other bodily exudates (e.g. menses, mixture of feces and urine, mixture of menses and urine, etc.) are well known in the art. Such articles are used to absorb, distribute and store various types of body exudates while providing a high level of comfort and sense of dryness to the wearer during use.
A conventional disposable absorbent article in the form of a diaper is normally designed with an absorbent core which is sandwiched between a topsheet and a backsheet. The article is arranged along a longitudinal axis and along a transversal axis which extends in a perpendicular direction in relation to the longitudinal axis. Furthermore, the article can be divided into a front portion, a back portion and a crotch portion.
When a user of absorbent article exudates fecal material (e.g. runny bowel movement, a mixture of bowel movement and urine, etc.) it is important that the absorbent article can handle the bodily exudates i.e. absorb and retain the fecal material within the absorbent article. Absorbent articles can efficiently handle this by having proper fit around the waist and the legs of the user, by having proper absorption of the bodily exudates and/or by having means for preventing fecal materials to leak out of the absorbent article.
Means for preventing fecal materials to leak out are frequently used in the art. One method is to prevent leakage of fecal material by providing a pocket on the back part of the absorbent article for collecting fecal material and avoid leakage through the waist of the user. The drawback with pockets and other means for prohibiting leakage of fecal materials is that during a rapid flow of bodily exudates the means for preventing leaks may not efficiently prohibit the fecal materials to be gathered and retained within the absorbent article. This problem occurs often when the flow of fecal material is high and/or when the absorbent core is expanded. A higher flow of fecal material often occurs when a person suffers from a virus or bacterial infection, allergic reaction or when performing a medicine cure, drinking breastmilk or a breastmilk substitute etc. The absorbent core may be expanded during the exudate of the fecal material if the user of an absorbent article for example has urinated prior to exudation of the fecal material.
Accordingly, there is an interest to provide means for retaining fecal materials within the absorbent article more efficiently i.e. means that prohibit the fecal materials to leak out of the waist of the diaper despite of the flow of the fecal material and/or despite the state of the absorbent core of the absorbent article.
A previously known absorbent article of the above-mentioned kind is disclosed in the patent document EP2750648A1. This document discloses an incontinence article of pants-type for holding bodily excretions. The rear end area of the absorption structure is covered by a flat-material section which is joined inseparably to the crotch portion to form a pocket.
Even though the article disclosed in EP2750648A1 fulfills certain requirements related to preventing fecal materials to leak, there is still a need for further improvements in order to provide an absorbent article being able to provide this feature in a more efficient manner.
The present disclosure is based on the insight that the ability of an absorbent article such as for example a diaper to avoid leakage may be challenged under certain conditions.
The present disclosure relates to an absorbent article comprising a liquid-permeable topsheet, a liquid impermeable backsheet and an absorbent core positioned intermediate the liquid permeable topsheet and the liquid impermeable backsheet, each layer having a skin-facing side and a garment-facing side, wherein said absorbent core comprises a thickness, said absorbent article being arranged along a longitudinal axis and a transversal axis extending in a perpendicular direction in relation to the longitudinal axis, and said absorbent article defining a front portion having a front edge, a back portion having a back edge and a crotch portion intermediate said front portion and said back portion, wherein said back portion of said absorbent article further comprises a transversally extending capture layer, wherein said capture layer comprises an outboard transversal edge facing said back edge and two longitudinal edges being sealed to any part of said absorbent article, wherein said capture layer further comprises an inboard transversal edge facing said front edge, said inboard transversal edge being unsealed for gathering of feces, wherein said capture layer is positioned to at least partially cover the skin-facing side of the topsheet, wherein said absorbent core comprises at least one thickness, wherein at least said back portion of said absorbent article further comprises at least one centrally oriented zone in said absorbent core, said zone comprising a thickness, wherein said zone is at least partially recessed, resulting in said zone having a generally lower thickness in relation to the thickness of surrounding parts of the absorbent core.
The at least one zone may extend longitudinally from the back transversal edge of the absorbent core.
Further, said at least one zone may have a lower basis weight in relation to surrounding parts of the absorbent core.
The inboard transversal edge of the capture layer may at least partially overlap the at least one zone.
The at least one zone may further comprise a length, wherein the absorbent core comprises a length, wherein the length-ratio between the at least one zone and the absorbent core may be within the interval 0.04-1.
The at least one zone may further comprise a width and the absorbent core may comprise a width, wherein the width-ratio between the at least one zone and the absorbent core may be within the interval 0.02-0.8, preferably within the interval 0.02-0.28.
The capture layer may comprise at least one transversally extending elastic strand positioned between a pair of sealed layers of material.
Furthermore, the at least one zone may extend along the entire longitudinal length of the absorbent core.
The at least one zone may be fully recessed.
The at least one zone may be shaped generally as a semi-circle, a U-shape, a V-shape, a circular shape, an oval shape or a rectangular shape extending towards the front edge in the longitudinal direction.
The absorbent core may be enclosed by a core cover comprising a top-layer and a bottom-layer, wherein at least a part of the topsheet or an intermediate layer is joined to said top-layer, wherein the top-layer and the bottom-layer are joined together in at least the area comprising the fully recessed zone.
The basis weight of the at least one zone may be within the interval of 0-200 g/m2, wherein the basis weight of surrounding parts of the absorbent core may be within the interval of 50-800 g/m2.
The said at least one zone may be divided in said back portion into two oblong channels extending longitudinally to at least said crotch portion of said absorbent article.
The absorbent article may comprise two centrally oriented zones extending from said back portion to at least said crotch portion.
There is further also provided a method for manufacturing an absorbent article, comprising a liquid-permeable topsheet, a liquid impermeable backsheet and an absorbent core positioned intermediate the liquid permeable topsheet and the liquid impermeable backsheet, each layer having a skin-facing side and a garment-facing side, said absorbent article being arranged along a longitudinal axis and a transversal axis extending in a perpendicular direction in relation to the longitudinal axis, and said absorbent article defining a front portion having a front edge, a back portion having a back edge and a crotch portion intermediate said front portion and said back portion, said method comprising:
Further advantages and advantageous features of the disclosure are disclosed in the following description.
The disclosure will be described in greater detail below with reference to the figures shown in the appended drawings.
Different aspects of the present disclosure will be described more fully hereinafter with reference to the enclosed drawings. The embodiments disclosed herein can, however, be realized in many different forms and should not be construed as being limited to the aspects set forth herein.
The term “absorbent article” refers to a product that is configured to be worn on or around the lower torso of the body of a human wearer. The absorbent article is intended to absorb and/or contain body exudates, such as urine, feces and menses fluid. Absorbent articles include for example open absorbent articles, pant-type absorbent articles and belt-type absorbent articles, being able to be worn without the support from underwear. The absorbent article may be a disposable absorbent article.
The “body facing side” of the absorbent article refers to the side facing the wearer during use and the “garment-facing side” refers to the side facing away from the wearer during use. The garment facing side and the body facing side are thus facing away from one another.
An “open type absorbent article” relates to an absorbent article having fastening elements arranged to connect the front portion with the back portion when the article is being worn.
A “pant type absorbent article” relates to an absorbent article wherein the front portion and back portion are permanently connected prior to use, forming a waist opening and a pair of leg openings.
The term “capture layer” refers to at least one sheet of suitable material arranged on the skin-facing side of the topsheet to form a pocket-like structure. The opening of the pocket is arranged to gather body exudates from a user.
The term “zone” refers to a part of the absorbent core that differs in properties and/or dimensions in relation to surrounding parts of the absorbent core not encompassing the zone.
The term “topsheet” refers to a fluid pervious body facing structure that may be sufficiently liquid-permeable to allow discharged body fluids to penetrate through its thickness. The topsheet may be suitably manufactured from a material which is compliant and soft-feeling to the skin of the wearer. The topsheet may consist of a single layer or have a laminate structure comprising a plurality of layers, for example, two or more layers. The layers may be made of the same material, or some or all the layers may be made of different materials. The topsheet material may be of a nonwoven, a film or a laminate thereof or of a foam. The material may be of thermoplastic synthetic or natural fibers, or a mixture thereof. Natural fibers may be e.g. cotton or pulp fibers and synthetic fibers may be e.g. of a polyester such as PET or a polyolefin such as polyethylene or polypropylene, or a combination of these fibers. The nonwoven may be formed by a variety of different processes, such as spun bonding, air laying, melt blowing or bonded carded web formation processes. The nonwoven layer may be made of an SMS (spun bond/melt blown/spun bond) or SS (spun bond/spun bond) nonwoven material of polypropylene or bicomponent fibers of polypropylene and polyethylene, or of a combination of such materials. The topsheet layer or layers may be apertured or non-apertured and may have imparted hydrophilic properties to improve liquid drainage of the structure. The topsheet may have a basis weight in the range of 5-50 g/m2.
The term “backsheet” refers to the sheet which is facing away from the user during use and is opposite to the body facing topsheet layer of the absorbent article. The backsheet may be a liquid-impermeable or fluid repellant structure. The backsheet material may be of a breathable or non-breathable material such as a of a film, a nonwoven or a laminate thereof, or a foam. The backsheet may have a laminate structure comprising a liquid barrier film and a nonwoven layer arranged on top of each other, wherein the nonwoven layer is arranged at an outer side away from the wearer of the absorbent article when worn. The backsheet may be elastic in any direction.
The film may be of a thermoplastic polymer, e.g. a polyester such as PET or of polyolefins such as of polyethylene or polypropylene, or a mixture thereof. It may be a single layer film or a multi-layer film.
The nonwoven may be of thermoplastic polymer material fibers or filaments e.g. a polyester such as PET or of polyolefins such as of polyethylene or polypropylene, or a mixture thereof. The nonwoven may be formed by a variety of different processes, such as spun bonding, air laying, melt blowing or bonded carded web formation processes. The nonwoven layer may be made of an SMS (spun bond/melt blown/spun bond) or SS (spun bond/spun bond) nonwoven material of polypropylene or bicomponent fibers of polypropylene and polyethylene, or of a combination of such materials.
Forming the liquid barrier film of a plastic material, such as a thermoplastic film material, allows for a particularly good printability of the liquid barrier sheet. The liquid barrier sheet may also contain cellulose fibers.
The liquid barrier film may consist of a single layer or have a laminate structure with a plurality of layers, e.g., two or more layers, three or more layers, or four or more layers. The layers of the laminate structure may be laminated, bonded or attached to each other, for example, by thermo and/or mechanical bonding, such as thermo-sealing, ultrasonic bonding, such as ultrasonic welding, an adhesive or adhesives, stitching or the like.
The liquid barrier sheet may be a breathable microporous film. The microporous film may be made of a material comprising at least two basic components, namely a thermoplastic elastomeric polyolefin polymer and a filler. These components and, in some embodiments, additional other components may be mixed together, heated and subsequently extruded into a mono-layer or multi-layer film using any one of various film-producing processes, such as cast embossed, chill and flat cast, and blown film processes.
The term “absorbent core” refers to the unit placed intermediate the topsheet and the backsheet. The absorbent core can be of any conventional kind. Examples of common absorbent materials used in absorbent cores are cellulosic fluff pulp, tissue layers, highly absorbent polymers (so called superabsorbents), absorbent foam materials, absorbent nonwoven materials or the like. It is common to combine cellulosic fluff pulp with superabsorbent polymers (SAP) in an absorbent core.
It is conventional in absorbent articles to have an absorbent core comprising layers of different properties with respect to liquid receiving capacity, liquid distribution capacity and storage capacity. The thin absorbent bodies, which are common in for example baby diapers and incontinence articles, often comprise a compressed mixed or layered structure of cellulosic fluff pulp and superabsorbent polymers. The size and absorbent capacity of the absorbent core may be varied to be suited for different absorbent article sizes or different uses such as for infants or for adult incontinent persons. The term “absorbent core” as discussed herein, does not encompass the core cover. The form of the absorbent core may be varied, as will be discussed herein.
With initial reference to
As shown in
Further, an acquisition and distribution layer (ADL) may be arranged as an intermediate layer between the absorbent core 4 and the topsheet 2. The acquisition layer may be adapted to quickly receive and temporarily store discharged liquid before it is absorbed by the absorbent core 4. The polymer materials of the ADL may be non-absorbent materials which do not retain any fluid in the material itself. The function of the ADL is to provide the absorbent article 1 with temporary fluid holding capacity and to distribute fluid in the article. As the polymer materials in the fluid flow control structure may be hydrophobic and may have a wetting angle (θ) of 90° or close to 90° implying that they have no or very low wettability when contacted with aqueous fluids. The components of the fluid flow control structure may be treated to lower the wetting angle and render them hydrophilic, i.e. wettable by body fluids. A perfectly wettable material has a wetting angle (θ) of 0°. Any commonly known method for rendering a hydrophobic material hydrophilic may be used, such as treatment with surfactants, plasma or corona treatment, etc. A hydrophilic material facilitates liquid penetration and draining, thus maintaining free volume capacity for the next gush of liquid. An ADL may be composed of for example air laid, nonwoven, high loft nonwoven or foam materials. An air laid may be produced with fluff, wood pulp, and here the fluff fibres are dispersed into a fast-moving air stream and condensed onto a moving screen by means of pressure and vacuum. The ADL may be of a non-perforated nonwoven material or a perforated material.
As disclosed in
Furthermore, the absorbent article 1 may have a pair of standing gathers, which extend upwardly generally about respective side edges of the absorbent core 4 at the side of the topsheet 2. Such a standing gather defines a barrier or wall at the respective side edges of a central crotch portion 7 of the absorbent article 1, which acts to prevent or retard lateral flow of body fluidic material such as urine or fluidic fecal material.
The standing gathers may run substantially parallel to the longitudinal edges at the crotch portion 7 in a longitudinal direction of the absorbent article 1. The standing gathers may contain elastics and may include an elastic material, such as an elastic thread, yarn or ribbon material, and may be elastically gathered at least in their center portions, which provide means for a good fit so as to prevent any leakage. The standing gathers may extend in the longitudinal direction y over the entire length of the absorbent article 1. It will be appreciated, however, that, the standing gathers may be shorter.
Furthermore, at least one longitudinal leg elastic element 24 may be arranged in the crotch portion 7 at each longitudinal side that may extend at a side outside each one of the standing gathers along the longitudinal direction y thereof. Each longitudinal side may at least in part be made of the standing gather sheet material. Upon use of the absorbent article 1, the elastic elements may provide that the longitudinal sides are elastically gathered and serve as leg elastic, which in turn provides an extra leakage barrier and a good fit to the wearer.
The outboard transversal edge 9 and the two longitudinal edges 10, 11 of the capture layer are sealed to any part of the absorbent article 1. It may be sealed by bonding technique such as glue, mechanical bonds, thermal bonds or any other suitable sealing method. Based on this, the outboard transversal edge 9 and the two longitudinal edges 10, 11 may be sealed to any part of the back portion 5 of the absorbent article 1 such as to the topsheet 2 or the standing gathers or a combination thereof. The inboard transversal edge 12 is not sealed to any part of the absorbent article 1 or may be partially sealed to any part of the absorbent article 1. Based on this, the capture layer 8 is constructed to function as a pocket, having three sealed side edges, and one unsealed edge. It should be noted that the inner parts of the capture layer 8 has to be at least partially unsealed in order for the pocket-function to operate i.e. all edges except the inboard transversal edge 12 are sealed and the other portions of the capture layer 8 form a cavity/pocket for collection of body exudates. The advantage of this construction is that the capture layer 8 is able to gather bodily exudates from a user flowing towards the back edge 15 of the absorbent article 1, thereby preventing unwanted leakage. As disclosed in
The capture layer 8 may comprise of at least one transversally extending elastic strand positioned intermediate at least one pair of sealed layers of sheet material, this structure may be achieved when the elastic layer is stretched in at least one direction before laminating it together with two or more inelastic layers. After the tension is removed from the elastic layer it can freely retract to its un-tensioned state. The capture layer 8 may consist of a first sheet and a second sheet and at least one elastic strand of an elastomeric construction with adhesive composition adhered between the first facing sheet and the second facing sheet. Further, the pair of sealed layers of sheet material could be two or more sheets placed upon one another or consist of a folded structure. Furthermore, if the absorbent article 1 is in the form of a pant diaper the capture layer 8 may be a part of the waist section of the absorbent article 1, in other words, the front region 5 and back region 6 of the pant-diaper being permanently connected prior to use may also form a pocket on the back portion 5 of the absorbent article 1. The capture layer 8 may be corrugated. The capture layer 8 comprises a garment facing side, and a skin-facing side. The material of the capture layer may be a nonwoven material, a film, a laminate, an elastic film, an elastic laminate or a combination thereof. An example of a material combination for the structure of the capture layer 8 is that the garment facing side of the capture layer 8 consists of a film and the skin-facing side of the capture layer 8 consists of a nonwoven material. The benefit of such a material formation is that the film may be more liquid-impermeable and hence help the body exudates to stay within the pocket. Further, the benefit of having a nonwoven layer on the skin-facing side of the capture layer 8 is more comfortable against the skin of the user of the absorbent article 1.
The inboard transversal edge 12 of the capture layer 8 may have different forms, such as a transversal line as shown in
As seen in
Further, the elastic side panels 18, 19 may be an extension of the capture layer 8 where the capture layer 8 is one sheet with fastening means 23 on its both distal ends located at the longitudinal edges of the capture layer 8, in other words, the elastic side panels 18, 19 and the capture layer 8 may be one interconnected elastic sheet structure that is extending transversally over the width of the absorbent article 1 and further extending transversally outside said width to form the pair of elastic side panels 18, 19. The benefit of having the capture layer 8 and the pair of elastic side panels 18, 19 on one sheet could be that the production and assembly costs of the diaper will be lower since the diaper will require less material and processes during manufacturing.
As shown in
The benefit of having a lower basis weight in the zone 13 compared to surrounding parts of the core 4 is that the zone 13 may achieve a generally lower thickness t1 compared to the thickness t2 in surrounding parts of the absorbent core 4 by having a lower basis weight.
The thickness may be measured under a pressure of 0.5 kPa, using a thickness gauge foot with dimensions 50×50 mm. The thickness is measured on several spots to obtain a representative mean.
The benefit of having a centrally oriented zone 13 with a generally lower thickness t1 compared to the thickness t2 of surrounding parts of the absorbent core 4 is that firstly, the gluteal cleft is centrally located on the body, hence the central location of the zone 13, further the generally lower thickness t1 of the zone 13 results in the pocket formed under the capture layer 8 having more volume to more efficiently gather bodily exudates. Furthermore, when a user wears the absorbent article 1 and subsequently puts pressure on the absorbent core 4 by means of sitting, lying down or any other way, the at least partially recessed zone 13 will contribute to being exposed to a lower pressure N/m2 compared to the surrounding parts of the absorbent article 1, in other words, the force per m2 will be lower in the area of the zone 13 compared to the surrounding parts of the absorbent article 1. This may result in that the surrounding parts of the absorbent article 1 will have a pressure receiving function, as a consequence, the bodily exudates will be prevented to flow in the surrounding parts of the absorbent core 4 and instead flow into the zone 13 and further into the pocket i.e. beneath the capture layer. Hence, the zone acts as a pressure-relieving area. Since the zone area 13 is exposed to a lower pressure and situated centrally, the bodily exudates will tend to flow within the zone area 13 and further into the pocket. Furthermore, generally when a user uses an absorbent article 1 and for instance is sitting down, the least amount of pressure on the absorbent article 1 from the user stems from the groove of the rear of the user, hence when a user exudates fecal material, it tends to flow within the groove of the rear of the user. Based on this, having the zone 13 at least partially aligned with said groove, will create a distance below the garment-facing side of the capture layer 8 and further help fecal material to more efficiently enter the pocket.
The zone 13 may be formed by compression of the absorbent core 4. The zone 13 may be formed by having a higher concentration of SAP on the surrounding parts of the zone 13 than on the zone area 13 in the absorbent core 4. The zone 13 may have a SAP concentration within the range of 0-40%, wherein the surrounding parts of the absorbent core 4 may have a SAP concentration within the range of 20-100%. Based on the above, the absorbent article 1 may comprise an unused state and a expanded state, wherein the thickness t1 of said zone 13 and the thickness t2 of the surrounding parts of the absorbent core 4 may be generally equal during the unused state of said absorbent article 1, wherein the thickness t2 of said surrounding parts of the absorbent core 4 may be generally greater than the thickness t1 of said zone when said absorbent core 4 is in a expanded state. In other words, the zone 13 may be constructed to have the same thickness t1 as the surrounding parts of the absorbent core 4 during its unused or dry state i.e. t1=t2. During swelling of the absorbent core 4, the zone 13 will achieve a lower thickness compared to surrounding parts of the absorbent core i.e. t2>t1. The unused state of the absorbent core 4 is the state where the absorbent article 1 is dry and no bodily exudates have been absorbed by the absorbent article 1. The expanded state is when the SAP in the absorbent core 4 have absorbed any bodily exudates.
The zone 13 may comprise a length l1 and the absorbent core 4 may comprise a length l2. The length l1 of the zone and the length l2 of the absorbent core 4 may be the same, in other words, said zone 13 may extend along the entire longitudinal length of the absorbent core 4, this is further disclosed in
The length-ratio between said zone 13 and said absorbent core 4 may be within the interval 0.04-1. The length-ratio is measured by dividing the length of the zone 13 with the length of the absorbent core 4. Further the zone 13 may comprise a width w1 and the absorbent core 4 may comprise a width w2, wherein the width-ratio between said zone 13 and said absorbent core 4 may be within the interval 0.02-0.8, preferably within 0.02-0.28. The width-ratio is measured by dividing the width of the zone 13 with the width of the absorbent core 4.
The absorbent article 1 of
Further, the inboard transversal edge 12 of said capture layer 8 may at least partially overlap said zone 13. This is further shown in
The absorbent article 1 may have two centrally oriented zones 13 extending from said back portion 6 to at least said crotch portion 7 as depicted in
The absorbent articles 1 shown in
The invention may be an array of disposable pant-type absorbent articles 1 comprising two or more sizes. Absorbent articles 1 in the array may be manufactured and/or distributed by a single manufacturer, under a common brand name and/or under a common tradename or trademark. In certain embodiments, the array comprises absorbent articles 1 of different sizes. Additionally, or alternatively, the array may comprise absorbent articles 1 suited for different wearer and/or purchaser segments.
There is also provided a method for manufacturing an absorbent article 1 comprising a liquid-permeable topsheet 2, a liquid impermeable backsheet 3 and an absorbent core 4 positioned intermediate the liquid permeable topsheet 2 and the liquid impermeable backsheet 3, each layer having a skin-facing side and a garment-facing side, wherein said absorbent core 4 comprises a thickness t2, said absorbent article 1 being arranged along a longitudinal axis y and a transversal axis x extending in a perpendicular direction in relation to the longitudinal axis y, and said absorbent article 1 defining a front portion 5 having a front edge 14, a back portion 6 having a back edge 15 and a crotch portion 7 intermediate said front portion and said back portion, said method comprising:
The disclosure may be varied within the scope of the appended claims. For example, the absorbent article may further include leg elastics, prints, apertures, embossments, waist elastics etc as known to the skilled man in the art depending of the type of absorbent article intended.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/SE2019/050550 | 6/11/2019 | WO | 00 |
