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EP-4740922-A2 - ABSORBENT ARTICLE WITH CHANNELS AND METHOD FOR MANUFACTURING THEREOF

EP4740922A2EP 4740922 A2EP4740922 A2EP 4740922A2EP-4740922-A2

Abstract

An absorbent article comprising a liquid pervious topsheet, a liquid impervious backsheet, and an absorbent core comprising an absorbent material between a top core wrap sheet and a back core wrap sheet, said absorbent core being positioned in between said topsheet and said backsheet, said absorbent core having a first and second side edge, a front edge and a rear edge, wherein the absorbent core is provided with a plurality of attachment zones where the top core wrap sheet is attached to the back core wrap sheet, and where substantially no absorbent material is present, wherein, seen in a longitudinal direction of the absorbent core, looking from the front edge to the rear edge, the absorbent core comprises subsequently a first, second, third, fourth and fifth zone.

Inventors

  • VAN INGELGEM, WERNER
  • SMET, STEVEN
  • Derycke, Tom
  • VERDUYN, Dries

Assignees

  • Drylock Technologies NV

Dates

Publication Date
20260513
Application Date
20180514

Claims (15)

  1. An absorbent article comprising a liquid pervious topsheet, a liquid impervious backsheet, and an absorbent core (130) comprising an absorbent material between a top core wrap sheet and a back core wrap sheet, said absorbent core being positioned in between said topsheet and said backsheet, said absorbent core having a first and second side edge (131, 132), a front edge (133) and a rear edge (134), wherein the absorbent core is provided with a plurality of attachment zones (140, 150, 160, 170) where the top core wrap sheet is attached to the back core wrap sheet, and where substantially no absorbent material is present, wherein, seen in a longitudinal direction of the absorbent core, looking from the front edge to the rear edge, the absorbent core comprises subsequently a first, second, third, fourth and fifth zone (Z1, Z2, Z3, Z4, Z5); wherein the absorbent core comprises a front part (130a) extending between the front edge and a transverse crotch line (L) of the absorbent core, and a rear part (130b) extending between the rear edge and the transverse crotch line of the absorbent core; wherein said first, second and third zone extend in the front part of the absorbent core and said fourth and fifth zone extend in the rear part; wherein in said first and fifth zone substantially no permanent attachment zones with a liquid guidance or distribution function are present; wherein said second zone comprises at least a first elongate front attachment zone (130, 140) of the plurality of attachment zones, said first front attachment zone extending from an edge of the first zone in the direction of the third zone; wherein at least said fourth zone comprises at least a first rear elongate attachment zone (160, 170) of the plurality of attachment zones, said first rear attachment zone extending from an edge of the fifth zone in the direction of the third zone; wherein at least one of said second, third and fourth zone comprises a bridge zone (B) allowing a liquid flow between the first and the second side edge by capillary action through the absorbent material and/or by mass flow.
  2. The absorbent article of claim 1, the bridge zone extends between the first front attachment zone and the first rear attachment zone, such that upon wetting of the absorbent material, a front and rear channel are created at said first front and rear attachment zone, respectively, wherein the bridge zone extends between said front and rear channel; wherein a minimum distance between the first front attachment zone and the first rear attachment zone is preferably larger than 3 mm more preferably larger than 5 mm.
  3. The absorbent article of any one of the previous claims, wherein the first rear elongate (160) attachment zone extends into the third zone.
  4. The absorbent article of any one of the previous claims, wherein a distance between the transverse crotch line and a transverse center line extending perpendicular on the longitudinal direction of the absorbent core, through the middle of the absorbent core, is smaller than 10%, more preferably smaller than 5% of the length of the absorbent core.
  5. The absorbent article of any one of the previous claims, wherein the first zone extends over a length corresponding with at least 5%, preferably at least 10% of the length of the absorbent core seen in the longitudinal direction; and/or wherein the fifth zone extends over a length corresponding with at least 10% of the length of the absorbent core seen in the longitudinal direction, preferably at least 20%, more preferably at least 25%.
  6. The absorbent article of any one of the previous claims, wherein the second, the third and/or the fourth zone each extends over a length corresponding with at least 10% of the length of the absorbent core seen in the longitudinal direction, preferably at least 15%.
  7. The absorbent article of any one of the previous claims, wherein said second zone comprises a second front attachment zone (150) extending next to the first attachment zone (140), seen in the longitudinal direction, wherein preferably the first front attachment zone and the second front attachment zone are arranged symmetrically with respect to a longitudinal center line of the absorbent core; wherein the distance between the first and the second front attachment zone is between 15 and 70% of the width of the absorbent core, more preferably between 20 and 50%.
  8. The absorbent article of any one of the previous claims, wherein said fourth zone comprises a second rear attachment zone (170) extending next to the first rear attachment zone (160), seen in the longitudinal direction, said second rear attachment zone extending preferably into the third zone, wherein preferably the first rear attachment zone and the second rear attachment zone are arranged symmetrically with respect to a longitudinal center line of the absorbent core; wherein preferably the distance between the first and the second rear attachment zone is between 5 and 60% of the width of the absorbent core, more preferably between 10 and 40%.
  9. The absorbent article of any one of the previous claims, wherein the bridge zone extends from a first portion of the absorbent core, preferably in the second or third zone, to a second portion of the absorbent core, preferably in the second or third zone, wherein the first portion is defined between the first side edge and a longitudinal center axis (CL) of the absorbent core and the second portion is defined between the second side edge and the longitudinal center axis (CL) of the absorbent core.
  10. The absorbent article of claim 7 and 8, wherein a first smallest distance (d12) between the first and the second front attachment zone is bigger than a second smallest distance (d34) between the first and the second rear attachment zone.
  11. The absorbent article of claim 7 and 8, wherein the first and the second front attachment zone extend in a longitudinal direction of the absorbent core over a length (11) which is less than the length (l3) of the first and second rear attachment zone.
  12. The absorbent article according to any one of the previous claims, wherein the length of the first front attachment zone is larger than 5% of the length of the absorbent core; preferably larger than 10%, more preferably larger than 15%; and/or wherein the length of the first rear attachment zone is larger than 5% of the length of the absorbent core; preferably larger than 10%, more preferably larger than 15%.
  13. An absorbent article of any one of the previous claims, wherein said plurality of attachment zones are permanent attachment zones which remain attached when wetted.
  14. The absorbent article of any one of the previous claims, wherein said plurality of attachment zones extend, seen in the transverse direction of the absorbent core, over the transverse distance which is at least 1 mm, preferably at least 3 mm, more preferably at least 4 mm, even more preferably at least 5 mm, most preferably at least 6 mm.
  15. The absorbent article of any one of the previous claims, wherein said bridge zone comprises one or more temporary attachments between the top and back core wrap sheet which are configured to detach when wetted; and/or wherein said bridge zone comprises at least one permanent attachment zone in a direction from the first to the second side edge; and/or wherein said bridge zone comprises absorbent material.

Description

TECHNICAL FIELD The present invention pertains to the technical field of absorbent articles, more preferably disposable personal care articles such as diapers, baby pants, adult incontinent garments, and the like, and to absorbent structures for use in such absorbent articles. More specifically the present invention relates to an absorbent structure comprising an absorbent core between a topsheet and a backsheet. The present invention also relates to a method and apparatus for manufacturing such an absorbent article. BACKGROUND Absorbent articles such as diapers, baby pants, adult incontinent garments and the like, typically comprise an absorbent core, positioned in between a liquid permeable or pervious, hydrophilic or semi hydrophilic topsheet and a liquid impermeable or impervious backsheet. The absorbent core comprises absorbent material that is able to absorb fluid and liquid bodily excretions of the user of the absorbent article. The absorbent material of the absorbent core may be an absorbent particulate polymer material which is dispersed in a matrix of cellulose fibers or fluff pulp in order to prevent the particulate material from aggregating, as well as to prevent gel blocking. Gel blocking can occur when the absorbent particulate polymer material absorbs liquid, as they tend to typically swell and form a gel structure. This gel structure often blocks the further transfer of liquid into the remaining absorbent core. As a result, the liquid may be unable to reach the remaining absorbent particulate polymer material and the efficiency of the overall absorbent article decreases significantly. Existing fluff pulp materials are not suited to cope with rapid, subsequent insults of fluid since they possess limited distribution capacities. Moreover existing fluff pulp materials exhibit a limited capacity of overall liquid intake. Furthermore, existing absorbent cores containing fluff pulp have a limited wet integrity, which leads to the shape and fit of the absorbent article being deformed when e.g. an absorbent article is being worn by a baby which moves around. In recent years, there has been a strong demand for more flexible, thinner, light-weight, absorbent articles to resolve various problems associated with manufacturing, marketing, design, fit, wearing comfort, distribution, garbage disposal, material and energy consumption, transport and storage costs and the like. This lead to the search for and the development and production of absorbent articles of which the absorbent cores contains little to no cellulose fibers or fluff pulp, as the latter tend to be quite bulky, thus rendering generally more thick absorbent cores which reduces the overall wearing comfort of the user of the absorbent article. Hence, various absorbent cores containing little to no cellulose fibers or fluff pulp were developed in the past few years to try and overcome the above drawbacks, whereby the relative high amounts of absorbent polymer materials necessary to replace the absorption, distribution and retention capacity of the excluded cellulose fibers and/or fluff pulp were loaded, distributed and immobilized within these new absorbent cores according to several techniques. However given the ability and capacity of the absorbent core to absorb, transport and retain fluid and liquids is heavily dependent upon the form, position and/or manner wherein these absorbent polymer materials are incorporated within the absorbent core several drawback remained unsolved. In general the substantially heterogeneously distributed absorbent cores having non-continuous compartments and/or clusters of absorbent polymer material have in general proven to be better in coping with the above mentioned problems, nevertheless they also proved to remain unsatisfactory within most of the available absorbent articles. Especially problematic however, were the substantially homogenously distributed absorbent structures having continuous layers of absorbent polymer particulate material given they exhibit a substantially homogenous swollen absorbent polymer material area for second, third and next liquid insults wherein the dry and/or wetted absorbent polymer material layer may actually act as a liquid barrier. These problems and complications are especially prevalent within very flexible, thin, lightweight absorbent structures wherein high amounts of absorbent polymer material are distributed within the absorbent core of the absorbent article. Adding even more, thicker and larger overlying acquisition and dispersing layers did not at all resolve the above cited absorption, distribution and retention problems and moreover made the absorbent articles commercially unviable, environmentally unsustainable and more difficult to manufacture, store and transport. Furthermore an existing problem which has been associated with such absorbent cores containing no or little cellulose fibers or fluff pulp is related to the migration, loss and leakage of the absorben