DISPOSABLE HYGIENE ARTICLE WITH IMPROVED FIT
20240016667 · 2024-01-18
Inventors
- Oscar Lipschutz (GÖTEBORG, SE)
- Louise Eliasson (GÖTEBORG, SE)
- Sofia Ekstedt (Göteborg, SE)
- Josefin Sohl (GÖTEBORG, SE)
Cpc classification
A61F13/4704
HUMAN NECESSITIES
A61F13/4756
HUMAN NECESSITIES
International classification
Abstract
Disclosed is a disposable hygiene article having a transverse direction, longitudinal direction and longitudinal centerline, the article having a front portion, crotch portion and rear portion, and including a liquid-permeable topsheet, a liquid-impermeable backsheet, and absorbent core arranged between the topsheet and backsheet, the topsheet and backsheet extending beyond the absorbent core to provide an outer boundary region of the article, the outer contour of the absorbent core being defined by mutually symmetrical mirror-imaged portions about the longitudinal centre line, the core including a neck region, the portion of the core forward of the neck region being defined as a head region and the portion of the core rearward of the neck being defined as the body portion, the article including at least one asymmetrical wing including an outer edge, the at least one asymmetrical wing outer edge meeting the disposable hygiene article at front and rear wing junctions.
Claims
1. Disposable hygiene article having a transverse direction, a longitudinal direction and a longitudinal centre line dividing the article into left-hand and right-hand portions, wherein said article has a front portion, a crotch portion and a rear portion, and said article comprises a liquid-permeable topsheet, a liquid-impermeable backsheet, an absorbent core arranged between the topsheet and the backsheet; wherein the topsheet and the backsheet extend beyond the absorbent core to provide an outer boundary region of the article that surrounds the absorbent core; wherein an outer contour of the absorbent core is defined by mutually symmetrical mirror-imaged portions arranged symmetrically about the longitudinal centre line, and defined by left and right core edge lines, the core extending between a core front edge in the front portion and a core rear edge in the rear portion. wherein the core comprises a neck region at which a transverse width between the left and right core edge lines) is smaller than a transverse width of the core forward of the neck region and a transverse width rearward of the neck region, wherein the portion of the core forward of the neck region is defined as a head region of the core and the portion of the core rearward of the neck is defined as the body portion; wherein the article further comprises at least one asymmetrical wing as seen along any transverse axis of the disposable hygiene article, the asymmetrical wing comprising an outer edge extending in an outward direction from the outer periphery of the disposable hygiene article, wherein the at least one asymmetrical wing outer edge meets the outer periphery of the disposable hygiene article at front and rear wing junctions connected via a wing junction line J.sub.w; wherein the outer edge of said at least one asymmetrical wing comprises a front wing distance point D.sub.f and a rear wing distance point D.sub.r, wherein the front wing distance point D.sub.f is being spaced from the junction line J.sub.w in an outboard transverse direction by a transverse distance J1 of 3 mm; wherein the core further comprises a first front conforming line and a second front conforming line, the first front conforming line being arranged symmetrically with the second front conforming line with respect to a longitudinal or a transverse axis, wherein the first front conforming line extends from an outer free end located on or adjacent to the left outer edge towards an inner end located on or adjacent to the longitudinal centre line along a first diagonal axis CL1 extending in the plane of the disposable hygiene article, and wherein the second front conforming line extends from an outer free end located on or adjacent to the left or right outer edge towards an inner end located on adjacent to the longitudinal centre line along a second diagonal axis CL2 extending in the plane of the disposable hygiene article, the first and the second diagonal axis converging at a convergence point C; wherein the first and second front conforming lines having a smallest transverse distance S therebetween at their closest approach, wherein the transverse distance S is 0 mm;
2. Disposable hygiene article according to claim 1, wherein a first longitudinal distance D.sub.C between the front wing distance point D.sub.f of said at least one asymmetrical wing and the convergence point C, as measured along the longitudinal centerline, is between 5-30 mm, preferably between 10-25 mm, and most preferably between 13-20 mm.
3. Disposable hygiene article according to claim 1, wherein said wing junction line J.sub.w corresponding to the wing length is between 50-110 mm, preferably between 75-100 mm, and most preferably between 85-95 mm.
4. Disposable hygiene article according to claim 1, wherein the width M between the left and right core edge lines in the neck region is between 30-60 mm, preferably between 32-42 mm.
5. Disposable hygiene article according to claim 1, wherein a front wing junction width W.sub.fwj between the left and the right front wing junctions, as seen in the transverse direction T, is between 75-95 mm, more preferably between 80-90 mm, and most preferably between 85-87 mm.
6. Disposable hygiene article according to claim 1, wherein a rear wing junction width W.sub.rwj between the left and the right rear wing junctions, as seen in the transverse direction T, is between 85-95 mm, more preferably between 87-93 mm, and most preferably between 88-91 mm.
7. Disposable hygiene article according to claim 1, wherein said second front conforming line 102 extends from an outer end located on or adjacent to the right outer edge towards an inner end located on or adjacent to the longitudinal center line.
8. Disposable hygiene article according to claim 7, wherein the first and second front conforming lines form at least a first front V having two arms extending from outer free ends located on or adjacent to the left and right core edge lines (8, 9) towards inner ends located on or adjacent to the longitudinal centerline, said inner ends separated by the distance S=0 at the closest approach V.sub.tip1, and wherein the closest approach V.sub.tip1 is positioned forward of the outer free ends of the arms.
9. The disposable hygiene article according to claim 1, said core (6) further comprising a first and a second rear conforming line.
10. The disposable hygiene article according to claim 9, wherein the first and second rear conforming lines form a rear V having two arms extending from outer free ends located on or adjacent to the left and right core edge lines towards inner ends located on or adjacent to the longitudinal centerline A, separated by the distance S0 at the closest approach, and wherein the closest approach is positioned rearward of the outer free ends of the arms.
11. The disposable hygiene article according to claim 1, wherein said core further comprises a third and a fourth front conforming lines forming a second front V having two arms extending from outer free ends located on or adjacent to the left and right core edge lines towards inner ends located on or adjacent to the longitudinal centerline A, separated by the distance S=0 at the closest approach V.sub.tip2, and wherein the closest approach V.sub.tip2 is positioned rearward of the outer free ends of the arms.
12. The disposable hygiene article according to claims 8, wherein said closest approach V.sub.tip1 of said inner ends of said first front V, and said closest approach V.sub.tip2 of said inner ends of said second front V coincide.
13. The disposable hygiene article according to claim 11, where a distance D.sub.v between the tip of the first front V V.sub.tip1 and the tip of the second front V V.sub.tip2 is between 0-10 mm, preferably between 2-6 mm and most preferably between 3-5 mm.
14. The disposable hygiene article according to claim 1, wherein said second front conforming line 102 extends from an outer end located on or adjacent to the left outer edge towards an inner end located on or adjacent to the longitudinal center line.
15. The disposable hygiene article according to claim 1, wherein said first and second front conforming lines are either a groove or a channel with a depth corresponding to 25% or more of a no-load thickness of the absorbent core, such as from 25% to 100% of the no-load thickness of the absorbent core, or a low density region in which the low density region has a density corresponding to 50% or less of the density of the absorbent core, the no-load thickness or the density of the absorbent core being measured in an area of the absorbent core being adjacent to first or second conforming line.
16. The disposable hygiene article according to claim 1, wherein said core comprises a first region comprising a head part and two leg portions extending symmetrically about the centre line in a longitudinal direction of the article, and wherein said absorbent core further comprises a second region at least partially surrounded by said first region, and wherein the second region has an average density which is at least 20%, preferably at least 30% and most preferably at least 50% lower than the average density of the first region.
17. Disposable hygiene article according to claim 16, wherein the two leg portions start and diverge from a common leg portion start point in the crotch portion and extend over a portion of the crotch portion towards separate leg portion endings in the rear portion, and wherein the second region extends between said leg portions in the transverse and longitudinal direction from the leg portion start point to an endpoint in the rear portion, and whereby a distance between facing sides of the respective leg portions in the transverse direction varies in the longitudinal direction, and a maximum distance between the facing sides of the respective leg portions in the transverse direction is in the crotch portion located at a position in the longitudinal direction corresponding to a position of a crotch point, and wherein said facing sides of the respective leg portions converge backwards in the longitudinal direction such that said distance is reduced from said maximum distance to a minimum distance.
18. Disposable hygiene article according to claim 1, wherein said at least one asymmetrical wing is formed with an outer edge comprising a wing positioning profile coinciding with a section of the outer edge, wherein the wing positioning profile is formed from a wave having a baseline X.sub.wp and a longitudinal axis Y.sub.wp perpendicular to the baseline X.sub.wp, said wave starting from the front wing junction and extending outwards, the wave consisting of a concave curve having a trough and a convex curve having a peak, the wing positioning profile ending at a wing positioning profile end point where said wave no longer coincides with said outer edge.
19. Disposable hygiene article according to claim 18, wherein the peak of the convex curve is located forward of the through of the concave curve as seen in the longitudinal direction y.
20. Disposable hygiene article according to claim 18, wherein the baseline X.sub.wp of the wave is placed perpendicular on the longitudinal centerline A of the disposable hygiene article.
21. Disposable hygiene article according to claim 18, wherein a distance W2 between the front wing distance point D.sub.fr and the peak of the convex curve of the wing positioning profile, as measured along the baseline X.sub.wp, is between 8-30 mm, preferably between 10-25 mm, and most preferably between 10-20 mm.
22. Disposable hygiene article according to claim 18, wherein a distance W1 between the front wing distance point D.sub.fr and the wing positioning profile end point, as measured along the baseline X.sub.wp, is between 13-35 mm, preferably between 16-25 mm.
23. Disposable hygiene article according to claim 18, wherein a height H between the through of concave curve and the peak of the convex curve of the wave, as measured along the longitudinal axis Y.sub.wp of said wave, is between 1-5 mm.
24. Disposable hygiene article according to claim 18, wherein the outer edge of said wing further comprises a rounded section formed with an arc of a circle and coinciding with the rounded section and having a defined radius r, said rounded section extending between a first point of the outer edge and a second point along said outer edge where said arc no longer coincides with said outer edge, wherein said radius r is within the interval of 40-500 mm.
25. Disposable hygiene article according to claim 18, wherein the outer edge of said wing further comprises two or more rounded sections formed with an arc of a circle and coinciding with the rounded section, each of said first and second arcs having a defined first and second radius, said first radius being within the interval of 40-500 mm and said second radius being within the interval of 40-500 mm.
26. Disposable hygiene article according to claim 18, wherein said outer edge includes at least one straight section.
27. Disposable hygiene article according to claim 18, wherein said wing defines a lower straight line along a lower edge section, wherein the lower straight line defines an angle with respect to a transverse axis X1 perpendicular to the longitudinal centerline A, the magnitude of the angle being between 30-60 degrees.
28. Disposable hygiene article according to claim 18, wherein said wing defines a lower straight line along a lower edge section, wherein the lower straight line defines an angle with respect to a transverse axis X1 perpendicular to the longitudinal centerline, the magnitude of the angle being between 5-30 degrees.
29. Disposable hygiene article according to claim 1, wherein said disposable hygiene article comprises a second asymmetrical wing as seen along any transverse axis of the disposably hygiene article, and wherein the first and the second asymmetrical wing are asymmetrical with respect to each other as seen along the longitudinal centerline.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] The present invention will be further explained hereinafter by means of non-limiting examples and with reference to the appended drawing wherein:
[0039]
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
DETAILED DESCRIPTION
[0047] The present disposable hygiene article is an absorbent article aimed for personal hygiene and may be for example a sanitary towel, a panty liner, or an incontinence pad. Such articles are commonly used for acquisition and storage of bodily exudates such as urine, faeces or menstrual fluid. The absorbent article is disposable, which means that it is intended to be used only once and disposed thereafter, rather than being cleaned and re-used. The absorbent article may suitably be a sanitary towel, and the design of the article is particularly suitable for sanitary towels.
[0048]
[0049] The article 1 comprises a front portion 2, a crotch portion 3, and a rear portion 4. The article 1 comprises a liquid-permeable topsheet 30, a liquid-impermeable backsheet 31, and an absorbent core 6 arranged between the topsheet 30 and the backsheet 31. The surface area of the topsheet 30 and the backsheet 31 extends beyond the surface area of the absorbent core 6 to provide for an outer boundary region 11 of the article surrounding the absorbent core 6. An outer contour of the absorbent core 6 is defined by mirror-imaged left and right core edge lines 8, 9, and the absorbent core 6 is delimited by a core front edge 7 in the front portion 2 and a core rear edge 10 in the rear portion 4.
[0050] The front portion 2 comprises a pair of front portion longitudinal side edges 2A and 2B which are connected by a front end edge 2C. The front portion longitudinal side edges 2A and 2B in
[0051] As shown in
[0052] In
[0053] The first region 12 comprises in the front portion 2 a head portion 14 and two leg portions 52, 53 extending symmetrically about a centre line A and in a longitudinal direction y of the article 1, starting from a leg portion start point a0 in the crotch portion 3 and extending over a portion of the crotch portion 3 towards separate leg portion endings 58, 59 in the rear portion 4. The outer contour of the head portion 14 is defined by two mirror-imaged substantially convex lines in respect to the longitudinal centre line A. The convex lines converge towards the core rear edge 10 and the first region rear edge 60 so as to define a neck for the first region 12, i.e. so as to define the narrowest width M in the transverse direction x for the first portion 12 between left and right first region edge lines 61, 62. The narrowest width M may be at the location of a transition 5, which is an area located between the front portion 2 and the crotch portion 3. Alternatively the narrowest width M is located in the front portion 2 and the transition 5 is located in the longitudinal direction between the narrowest width M and a transversal line crossing the start point a0 for leg portions 52 and 53 of the core.
[0054] As shown in the drawings, the absorbent core 6 further comprises a second region 50. The leg portions 52 and 53 have facing sides 54, 55, which together with a first region rear edge 60 define an outer contour for the second region 50 of the core 6. The second region 50 comprises a centre region 45 and a rear section 46. The portions of the facing sides that oppose each other in the rear section 46 are denoted with reference numerals 54 and 55 in
[0055] The crotch point is defined as a middle point of the centre region 45, which is located in a wetting area centrally in the crotch portion 3 of the article. The wetting area is the area where the liquid is initially expected to hit the article. In connection with articles adapted to absorb blood, such as sanitary napkins, it has been found that the crotch point should be located at the point being in contact with introitus. A longitudinal distance between a transversal line drawn between two points at opposite edges 61, 62 of the first region 12 of the core 6 at the point where the first region 12 has its narrowest width M, and the crotch point 80 may be about 57 mm when an average distance is calculated. This distance is indicated by reference sign d.sub.CP in
[0056] The facing sides 54, 55 of the respective leg portions 52, 53 converge backwards in the longitudinal direction y such that said distance ax is reduced from the maximum distance a1 to a minimum distance a2 between the rear parts 54, 55 of the facing sides.
[0057] The second region 50 is at least partially surrounded by the first region 12 and extends between the leg portions 52, 53 in the transverse direction x and in the longitudinal direction y from the leg portion start point a.sub.0 in the crotch portion 3 to a longitudinal endpoint al defining the extension of the leg portions 52, 53 in the rear portion 4. The leg portion start point a.sub.0 is located in the centre line A so that a symmetrical leg shape can be provided in each longitudinal portion I and II. A distance ax between facing sides 54, 55 of the respective leg portions 52, 53 in the transverse direction x varies in the longitudinal direction y. In this way portions having different extensions in the transverse direction are provided to improve the fit and the absorbent properties in the article. The facing sides 54, 55 of the respective leg portions 52, 53 converge backwards towards the rear edge of the article in the longitudinal direction y such that said distance a.sub.x is reduced from said maximum distance a.sub.1 to a minimum distance a.sub.2. The minimum distance is preferably located outside the wetting area located in the crotch portion and is located in the rear portion 4 of the article 1.
[0058] The centre region 45 of the second region 50 is located in the crotch portion 3, and a rear section 46 starts in the crotch portion 3 and extends into the rear portion 4 of the article 1. The second region 50 is surrounded by the first region 12, except in the first region rear edge 60 area of the core 6. The second region 50 suitably covers from 10-50%, such as from 20-40% of a total area of the core 6. The length of the second region 50 extending along the centre line A between the leg start point a0 an endpoint al in the rear portion 4 may vary greatly depending on the size of the article, but can be for example from 80 to 220 mm. The rear section 46 may have a length varying from for example 30-110 mm. The centre region 45 may have a length varying from for example 50-110 mm. The rear section 46 has a narrower width or extension in the transverse direction x than the centre region 45 or at least a portion of the centre region 45. The rear section 46 can have a lower average density of absorbent material than the centre region 45. Also the article in the rear section 46 has a lower stiffness than in the first region 12. Alternatively, the centre region 45 and the rear section 46 have substantially the same density. Thus, also the stiffness of the centre region 45 and the rear section 46 may be substantially the same.
[0059] The second region 50 which comprises the centre region 45 extending symmetrically about the centre line A, has a longer extension in the longitudinal direction y than in the transverse direction x. Suitably, the centre region has an oval shape or a shape of a parallelogram with edges being located along the centre line A and thus the centre region 45 extends longitudinally and symmetrically about the centre line A. The second region 50 further comprises a longitudinally and symmetrically about the centre line A extending rear section 46. The rear section 46 is in contact with the centre region 45 and can overlap with the centre region 45. Further, the rear section 46 is limited by the facing sides 54, 55 of the respective leg portions 52, 53 and the first region rear edge 60. The facing sides 54, 55 adjacent the rear section 46 can be curved or they can be straight and extend generally parallel to each other (as shown in
[0060] Generally, the absorbent core 6 has an asymmetrical shape in the longitudinal extension y, but the first and second longitudinal portions I, II are symmetrical in the transverse extension x about the centre line A. The core 6 may have different shapes, but the circumferential edges of the core 8,9 define a shape in which a head portion 13 and at least one neck area, i.e. an area with smaller width in the transverse direction x, is located in the front portion 2 or in the transition area 5 of the core 6. In this way, the article 1 can better conform to the body shape in the area where the front portion 2 transitions to the crotch portion 3. Practically this means i.a. that the article 1 can bend in a transversal direction x more easily in the area of the neck portion. Therefore, the front portion 2 and the core head portion 14 can bend towards the user and thus the front portion 2 can better cover the pubic regions of the wearer while the crotch portion 3 is able to locate close to the genital area of a female wearer. Also the article 1 will better be held in its position during the use. The neck area of the core 6 may be the same where the first region 12 of the core 6 has its narrowest width M or it may be distanced from that.
[0061] First and second front conforming lines 101, 102 are provided in the core 6. The first front conforming line 101 extends from the left core edge line 8, or from about the left core edge line 8, towards the longitudinal center line A along a first diagonal axis CL1 extending in the plane of the disposable hygiene article. A second front conforming line 102 extends from the right core edge line 9, or from about the right core edge line 9, towards the longitudinal center line A along a second diagonal axis CL2 extending in the plane of the disposable hygiene article. As shown in
[0062] The second front conforming line 102 is configured as a mirror image of the first conforming line 101, as shown in
[0063] As shown in
[0064] An advantage of the present disclosure is that the first and second conforming lines 101, 102 provide preferential folding of the article in a controlled manner. For example, in use the transition 5, or transition area 5, of the absorbent article 1 is positioned between the muscle tendons. The transverse compression of the longitudinal core side edges between the thighs of the user causes the article to crumple or fold. In articles comprising a core of uniform density and thickness, folding of the article occurs in an uncontrolled or unpredictable manner. As the article folds, creases or channels can form, running towards the edges of the article, which may result in leakage.
[0065] By providing conforming lines along which the article can fold or deform when compressed, the position of the folds and creases can be controlled in such a manner that the risk of leakage is minimised. However, the position of conforming lines should be carefully considered to avoid that other properties of the article are not unduly compromised. For example, the conforming lines should not weaken the structure of the article to such a degree that it becomes prone to tearing. In embodiments of the present disclosure, the first and second conforming lines 101, 102 provide preferential folding of the article in a controlled manner, to the edges of the core 6. In particular, the transverse compression of the left and right core edge lines 8, 9 of the core between the tendons allows the front portion 2 to fold along the conforming lines 101, 102 to upwardly in a forward direction towards the user's body. This allows closer, more secure fit of the article 1.
[0066] The first and second conforming lines 101, 102 (and any additional conforming lines) may be provided by means of groove or line compressing the core 6 and optionally a liquid acquisition sheet 37 and/or topsheet 30 with high pressure compression from the topsheet 30 or backsheet side of the article (or both simultaneously). Conforming lines may also be created by removing pulp in said conforming lines to create a so-called channel. Further, a combination of the above-mentioned techniques may be used e.g. by creation of a channel and compressing the core. The backsheet of the article can be retained unacted and the liquid impermeability of the backsheet is not affected and can be maintained.
[0067] The positioning of the conforming lines 101, 102 can be chosen based on the anatomy of the average user, and adapted based on different user groups or different product uses. The dimensions can also be adapted based on the size and shape of the absorbent article into which the conforming lines are incorporated. The dimensions provided above are therefore exemplary dimensions based on the exemplary product shown in
[0068] In
[0069] Further exemplary embodiments of the first and second conforming lines are described with reference to
[0070] In an alternative embodiment shown in
[0071] In yet a further embodiment shown in
[0072] It will become clear that the conforming lines 101, 102 described with reference to
[0073] Turning back to
[0074] In the context of this application, the front wing junctions 19, 20 and the rear wing junctions 21, 22 are defined as follows and with reference to
[0075] The left and right wing 16, 17 further comprise a front wing distance point D.sub.fl, D.sub.fr and a rear wing distance point D.sub.rl, D.sub.rr located on the outer edge 38 of the left and right wing 16, 17. The front and rear wing distance points are spaced apart from the wing junction line J.sub.wL in an outboard transverse direction by a transverse distance J1 of 3 mm. To determine the location of the front and rear wind distance point, one should proceed as follows: an imaginary line K.sub.L, K.sub.R is drawn parallel to the wing junction line JwL, J.sub.wR at a distance J1 of 3 mm outboard of the respective wing junction line J.sub.wL, J.sub.wR. The intersection of the imaginary line K.sub.L, K.sub.R with the outer edge 38 on the forward side of the left and right wing determines the left and the right front wing distance points D.sub.fl, D.sub.fr respectively. Similarly, the intersection of the imaginary line K.sub.L, K.sub.R with the outer edge 38 on the rearward side of the left and right wing determines the left and the right rear wing distance points D.sub.rl, D.sub.rr respectively.
[0076] The presence of the neck region 13 allows the disposable hygiene article 1 to bend more easily in a transversal direction x in the area of the neck portion. Since the left and right wing 16, 17 secure the disposable hygiene article 1 in the crotch region of the underwear of the user, the position of the left and right front wing distance points D.sub.fl, D.sub.fr in relation to the neck determines the position of the neck portion in the user's underwear. As shown in
[0077] The crotch portion 3 of the article 1 is located adjacent to the front portion 2 in the longitudinal direction. In use, the crotch portion 3 lies between the legs of the user and covers a female user's genital region. In a sanitary napkin of the type shown in
[0078] The disposable hygiene article 1 in
[0079] The right wing in
[0080] In
[0081] In
[0082] The outer edge 38 of the wing 17 in
[0083] Generally, each of the fastening wingsreferred to as wings in the present disclosure 16 and 17 is provided with fastening means in the form of at least one adhesive area which is applied on the underside of each wing 16, 17, i.e. on the side which does not face the wearer.
[0084] The advantages of the present invention can be achieved with minimal disruption to or modification of known manufacturing techniques. In a production method suitable for manufacturing articles according to the invention, a liquid-permeable topsheet material layer, a liquid-impermeable backsheet material layer, and an absorbent material layer are fed into the manufacturing equipment. The core is arranged to be positioned in between the topsheet material layer and the backsheet material layer. An optional acquisition material layer is arranged to be positioned between the topsheet material layer and the absorbent material layer. In
[0085] The disposable hygiene article of the present disclosure comprises an absorbent core, which is indicated in the figures with reference sign 6. The absorbent core is the absorbent structure of the article which acquires and stores bodily fluids. The absorbent core may be of any conventional kind. Examples of commonly occurring absorbent materials are cellulosic fluff pulp, tissue, 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 in an absorbent core. Superabsorbent polymers are water-swellable, water-insoluble organic or inorganic materials capable of absorbing at least about 20 times their own weight of an aqueous solution containing 0.9 weight percent of sodium chloride. Organic materials suitable for use as a superabsorbent material can include natural materials such as polysaccharides, polypeptides and the like, as well as synthetic materials such as synthetic hydrogel polymers. Such hydrogel polymers include, for example, alkali metal salts of polyacrylic acids, polyacrylamides, polyvinyl alcohol, polyacrylates, polyacrylamides, polyvinyl pyridines, and the like. Other suitable polymers include hydrolyzed acrylonitrile grafted starch, acrylic acid grafted starch, and isobutylene maleic anhydride copolymers and mixtures thereof. The hydrogel polymers are preferably lightly cross-linked to render the material substantially water insoluble. Preferred superabsorbent materials are further surface cross-linked so that the outer surface or shell of the superabsorbent particle, fibre, flake, sphere, etc. possesses a higher crosslink density than the inner portion of the superabsorbent. The superabsorbent materials may be in any form suitable for use in absorbent composites including particles, fibres, flakes, spheres, and the like. A high absorption capacity is provided by the use of high amounts of superabsorbent material. Thin absorbent cores which are common in for example sanitary napkins, baby diapers and incontinence guards, 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 suit different product types, such as sanitary napkins for adult incontinent persons or panty liners.
[0086] Generally, the core can be of unitary construction, whereby for example the manufacturing process can be simplified. The phrase unitary construction in the present context is intended to mean that the absorbent core is constructed from essentially one type of material, this being essentially the same material, or essentially the same combination of two or more materials throughout the absorbent core. Variations in density and concentration of the material may occur, but these are limited to those which may be obtained without incorporation of regions which have been formed separately and then physically joined to each other. For example, when the absorbent core comprises a matrix of hydrophilic fibres and superabsorbent material as described above, the relative concentrations of superabsorbent material and fibres may be different in different parts of the core. However, the absorbent core of unitary construction does not comprise layers or laminates of different composition. Likewise, variations in the density or concentration of various components across the longitudinal direction, the transverse direction or the thickness direction of the absorbent core are acceptable, yet the core should not comprise areas or layers of different composition which are formed separately and later joined together.
[0087] A suitable technique for manufacturing the absorbent cores of the present disclosure is mat-forming through an air-laying process. In the process an air-permeable mould is provided. Fibrous material is air-laid into the mould and the mould is filled, whereby an absorbent core is produced in with a desired amount of fibrous material.
[0088] Generally, the absorbent core 6 has an asymmetrical shape in the longitudinal extension y, but the first and second longitudinal portions I, II are symmetrical in the transverse extension x about the centre line A. The core 6 may have different shapes, but the circumferential edges of the core 8,9 define a shape in which a head portion 14 and at least one neck area, i.e. an area with smaller width in the transverse direction x, is located in the front portion 2 or in the transition area 5 of the core 6. In this way, the article 1 can better conform to the body shape in the area where the front portion 2 transitions to the crotch portion 3. Practically this means i.a. that the article 1 can bend in a transversal direction x more easily in the area of the neck portion. Therefore, the front portion 2 and the core head portion 13 can bend towards the user and thus the front portion 2 can better cover the pubic regions of the wearer while the crotch portion 3 is able to locate close to the genital area of a female wearer. Also the article 1 will better be held in its position during the use. Furthermore, and referring again to
[0089] After the absorbent core 6 is produced, it can be pattern-compressed so that an absorbent core having regions with different densities is produced. Compressing may take place using any known means. The average density of the fibrous material in the low-compressed or non-compressed absorbent core corresponds to the average density of the absorbent core in the regions of lower average density, i.e. the second region 50. The absorbent core outside these regions, i.e. in the first region 12, is then compressed while within these regions, the core remains uncompressed.
[0090] Thus, the first region of the core is compressed more than the second region. Alternatively or additionally the first region is embossed to solely provide the higher compression or to further increase compression grade obtained by compression. If the compression and embossing are separate steps, the step of embossing of an embossing pattern can be performed simultaneously or subsequently with the compression to areas providing the first region. The embossing pattern is suitably visible through the top sheet. The compression and embossing can be performed through the topsheet or the backsheet side of the core.
[0091]
[0092] The absorbent article 1 according to the present disclosure may include a liquid acquisition sheet 37, which acts as a liquid distribution layer. The acquisition layer 37 can have different shapes, and can be adapted to suit the shape of the absorbent core. The acquisition layer 37 may extend 1-15 mm beyond the outer edge of the core 6 (preferably around the entire periphery of the core 6). In some embodiments, the acquisition layer 37 may extend up to 50 mm in certain regions of the absorbent article 1. This configuration can provide neat edges at the periphery of the article. The liquid acquisition sheet 37 is located between the topsheet 30 and the core 6 and is suitably placed on top of the absorbent core. The liquid acquisition sheet 37 is adapted to quickly receive and temporarily store discharged liquid before it is absorbed by the absorbent core 6. Such acquisition distribution layers may be composed of for example airlaid nonwoven, spunlace nonwoven, high loft nonwoven or foam materials. The nonwoven material may be hydrophilic. A hydrophilic material may be obtained by adding a surfactant.
[0093] An air laid nonwoven can 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 web can be bonded with resin and/or thermal plastic resin dispersed within the pulp. The web can be thermobonded (by heat), latex bonded (with adhesive) or multibonded (a combination of thermo and latex bonding) or mechanically bonded (high compression and temperature, bonding by hydrogen). The grammage of the airlaid nonwoven can suitably be from 50 to 100 gsm.
[0094] A high loft material is a nonwoven material and may be substantially free from absorbing fibres and superabsorbent material. The high loft nonwoven material may comprise thermoplastic polymer fibres, and may be selected from but not limited to, polyesters, polyamides and polyolefins such as polyethylenes (PE) and polypropylenes (PP), and may be a mixture of any of these. The high loft material refers to low density bulky fabrics, as compared to flat, paper-like fabrics. High loft webs are characterised by a relatively low density. This means that there is a relatively high amount of void space between the fibres. The high loft nonwoven fibrous layer of the invention may typically have a density below 0.200 g/cc (200 kg/m3), in particular ranging from 0.015 g/cc to 0.150 g/cc (15 kg/m3 to 150 kg/m3), in particular from 0.030 g/cc to 0.100 g/cc (30 to 100 kg/m3), for example 0.065 g/cc (65 kg/m3). The average density can be calculated by dividing the basis weight of the high loft layer by its thickness measured at a pressure of 0.5 kPa (see the method details further below). Normally the thickness of high loft materials is more than about 0.5 mm, such as more than 1 mm or suitably 1.5-2.0 mm, and the solid content is low, usually less than 15% by volume. The high loft nonwoven layer may advantageously be a spunmelt nonwoven. Spunmelt is a generic term describing the manufacturing of nonwoven webs directly from thermoplastic polymers. It encompasses 2 processes and the combination of both: spunlaid (also known as spunbond) nonwoven and meltblown nonwoven. In a spunlaid process, polymer granules are melted and molten polymer is extruded through spinnerets. The continuous filaments are cooled and deposited on to a conveyor to form a uniform web. Some remaining temperature can cause filaments to adhere to one another, but this cannot be regarded as the principal method of bonding. The spunlaid process has the advantage of giving nonwovens greater strength, but raw material flexibility is more restricted. Co-extrusion of second components is used in several spunlaid processes, usually to provide extra properties or bonding capabilities. In meltblown web formation, low viscosity polymers are extruded into a high velocity airstream on leaving the spinneret. This scatters the melt, solidifies it and breaks it up into a fibrous web. The liquid acquisition sheet material may be of a spunbonded material and may be a spunbond-meltbond-spunbond (SMS) material. The high loft nonwoven layer may in particular have a thickness ranging from 0.30 mm to 2.00 mm, for example 1.0 mm as measured at a pressure of 0.5 kPa (according to the test method referred to in PCT Application No. PCT/SE2017/050612). The grammage, i.e. basis weight of the high loft material may for example range from 15 gsm to 500 gsm, in particular from 30 gsm to 200 gsm, such as 30-90 gsm, for example 64 gsm.
[0095] According to a further variant, the liquid acquisition sheet 37 is a spunlace, also referred to as spunbond, nonwoven material. A spunlace nonwoven product is derived from a process of entangling a web of loose fibres through multiple rows of jets of water at high pressure; this process entangles the fabrics and interlinks the fibres. There are several terms for spunlace nonwoven fabric or spunlaced, such as jet entangled, needled, hydrogenentangled or hydraulic, but the term spunlace or spunlaced is the most popular in the nonwoven industry. The raw material for the acquisition sheet can be polypropylene (PP), polyethylene (PE) polyester (PET), polyamide (PA), cellulosic fibres or a combination of these and different weights and compositions are possible, such as viscose, polyester, cotton, nylon and microfibre, wherein viscose is the most commonly used raw material. Thus, if a combination of different fibres is used, this can be a mixture of fibres from different polymers, although each fibre can also include different polymers (e.g. PP/PE bi-component fibres or PP/PE copolymers). Where appropriate, the plastic film can consist of PE or PP, PET, PLA or amyl (or, for that matter, any other thermoplastic polymer), or a mixture or copolymers of the aforementioned polymers. The spunlace material usually comprises polypropylene or polyethylene fibres which provide for optimal comfort for the nonwoven material. Other suitable fibres for making the nonwoven material are for example natural fibres such as bamboo, cotton and flax. The grammage of the spunlace nonwoven material can be typically from 30-80 gsm.
[0096] The topsheet may include or consist of fibrous nonwoven layer(s) being spunbonded, meltblown, carded, hydroentangled, wetlaid. Suitable nonwoven materials can be composed of natural fibers, such as woodpulp or cotton fibers, synthetic thermoplastic fibers, such as polyolefins, polyesters, polyamides and blends and combinations thereof or from mixtures of natural and synthetic fibers. The materials suited as topsheet material should be soft and non-irritating to the skin and be readily penetrated by body fluid, such as menstrual fluid and urine.
[0097] The backsheet may consist of a thin plastic film, e.g. a polyethylene or polypropylene film, a nonwoven material coated with a liquid impervious material, a hydrophobic nonwoven, which resist liquid penetration. Laminates of plastic films and nonwoven materials may also be used. The backsheet material can be breathable to allow vapor to escape from the absorbent structure, while still preventing liquids from passing through the backsheet material.
[0098] The wing may consist of a seperate material attached to the longitudinal side edges (8, 9) of the outer periphery 18 of the disposable hygiene article 1. A suitable material may be any of the materials listed above in connection with topsheet and backsheet. Alternatively, the wing may consist of an extension of the topsheet or backsheet material, or both.
[0099] Although not shown in the figures, the absorbent article 1 defined above may comprise any attachment means known in the art to allow fastening to undergarments of a wearer. Such means may include a coating of adhesive or friction coating on the garment-facing surface of the article. Furthermore, the article 1 according to the invention comprises attachment flaps (wings) which extend in the transverse direction of the article 1 and are intended to be arranged around the crotch portion on the briefs of the wearer. It is however important that the nature and placement of such attachment means does not significantly interfere with the function of the article 1 in use.
[0100] The sanitary article according to the present disclosure may thus be provided with an adhesive, such as a pressure-sensitive adhesive on the backsheet. The elongated wrapping sheet may be releasably adhered the adhesive-bearing backsheet of the sanitary article. The wrapping sheet may be coated with material which enables the release of the wrapping sheet, such as silicone, so that the wrapping sheet may be peeled away from the adhesive-bearing backsheet of the sanitary article and so that the sanitary article may be attached to an undergarment. The adhesive-bearing region of the backsheet may also be covered with a release paper. The release paper may be attached to the wrapping sheet, for example with a permanent attachment, such that the sanitary article is attached to the wrapping sheet via the release paper.