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EP-4059482-B1 - A TRANSVERSELY EXTENSIBLE CONTINUOUS ELASTIC LAMINATE, AND A METHOD FOR PRODUCING THE SAME

EP4059482B1EP 4059482 B1EP4059482 B1EP 4059482B1EP-4059482-B1

Inventors

  • Gualtieri, Diego
  • CIPRIANI, ALESSANDRO

Dates

Publication Date
20260506
Application Date
20210319

Claims (15)

  1. A transversely extensible continuous elastic laminate (50) comprising: - a first and a second continuous web (10, 30) extending along a longitudinal direction (X), having respective pleated central portions (12, 32) having pleats (52, 54) parallel to said longitudinal direction (X) and respective first and second non-pleated edge portions (14, 34, 16, 36) on opposite sides of said pleated central portions (12, 32), - a continuous elastic tape (18) extending in said longitudinal direction (X), and sandwiched between said pleated central portions (12, 32) of said first and second web (10, 30), wherein said elastic tape (18) is elastically stretchable in a transversal direction (Y) transversal to said longitudinal direction (X), and wherein said continuous elastic tape (18) is joined to the first and second web (10, 30) by a pattern of spot welds (40), and - at least one row of tabs (58) protruding in said transversal direction (Y) beyond at least one of said non-pleated edge portions (14, 34, 16, 36), said tabs (58) being made of a non-woven material and having micro-hook fastening formations (22) integrally formed in the non-woven material forming said tabs (58).
  2. The transversely extensible continuous elastic laminate of claim 1, wherein said at least one row of tabs (58) includes a continuous edge portion (26) of a non-woven material extending in said longitudinal direction (X) and joined to one of said non-pleated edge portions (14, 34, 16, 36) of said first and second web (10, 30) by said pattern of spot welds (40), said tabs (58) transversely extending from said continuous edge portion (26), being connected to each other by said continuous edge portion (26) and being spaced apart from each other in said longitudinal direction (X) .
  3. The transversely extensible continuous elastic laminate of claim 1, wherein said at least one row of tabs (58) is formed by a portion of said first or second continuous web (10, 30).
  4. The transversely extensible continuous elastic laminate of claim 1, comprising a first and a second tab chain (66) of non-woven material having respective continuous longitudinal edge portions (26) joined to respective first and second non-pleated edge portions (14, 16, 34, 36) of the first and second continuous web (10, 30) and fixed thereto by said pattern of spot welds (40), and respective tabs (58) extending from the respective continuous longitudinal edge portions (26).
  5. The transversely extensible continuous elastic laminate of claim 4, wherein in each of said continuous tab chains (66) the respective tabs (58) are spaced apart from each other in said longitudinal direction (X) and wherein the tabs (58) of the two continuous tab chains (66) are offset with respect to each other.
  6. An elastic side panel for absorbent sanitary articles, comprising: - a first and a second web (10, 30), having respective pleated central portions (12, 32) having pleats (52, 54) parallel to a first direction (X), and respective first and second non-pleated edge portions (14, 34, 16, 36) on opposite sides of said pleated central portions (12, 32), - an elastic tape (18) sandwiched between said pleated central portions (12, 32) of said first and second web (10, 30), wherein said elastic tape (18) is elastically stretchable in a second direction (Y) transversal to said first direction (X), wherein said elastic tape (18) is joined to the first and second web (10) by a pattern of spot welds (40), and - a tab (58) protruding in said transversal direction (Y) beyond at least one of said non-pleated edge portions (14, 34, 16, 36), said tab (58) being made of a non-woven material and having a micro-hook fastening formation (22) integrally formed in the non-woven material forming said tab (58).
  7. The elastic side panel of claim 6, comprising a support web (20) of a non-woven material including an edge portion (26) joined to one of said non-pleated edge portions (14, 34, 16, 36) of said first and second web (10, 30) and fixed thereto by said pattern of spot welds (40), said edge portion (26) having in said first direction (X) the same length as said non-pleated edge portion (14, 34, 16, 36), the support web (20) including an integral tab (58) extending from said edge portion (26).
  8. The elastic side panel of claim 6, wherein said tab (58) is integrally formed with said first and/or second web (10, 30).
  9. An absorbent sanitary article comprising an absorbent central body and two or four elastic side panels (60) according to any of claims 6-8 fixed to two opposite longitudinal edges of said central body.
  10. A method for producing a continuous transversely extensible elastic laminate (50) comprising: - feeding in a longitudinal direction (X) two first continuous webs (10), the two first continuous webs (10) being spaced from each other in a transverse direction (Y) and having respective central portions (12) and respective first and second edge portions (14, 16) on opposite sides of the respective central portions (12), - feeding in said longitudinal direction (X) two continuous elastic tapes (18), - elastically stretching said two continuous elastic tapes (18) in a transverse direction (Y) transversal to said longitudinal direction (X), and applying said two continuous elastic tapes to respective central portions (12) of said two first continuous webs (10) while stretched in said transversal direction (Y), - feeding in said longitudinal direction (X) a continuous support web (20) of a non-woven material having two continuous edge portions (26), the continuous support web (20) having a micro-hook formation (22) integrally formed in the non-woven material forming said support web (20), - applying said two continuous longitudinal edge portions (26) of said support web (20) to respective first edge portions (14) of said two first continuous webs (10), - feeding in said longitudinal direction (X) two second continuous webs (30) spaced from each other in said transverse direction (Y) and having respective central portions (32) and respective first and second edge portions (34, 36) on opposite sides of the respective central portions (32), - applying said two second continuous webs (30) to respective first continuous webs (10) and sandwiching said two continuous elastic tapes (18) between respective central portions (12, 32) of said first and second webs (10, 30), - joining to each other said two first and second webs (10, 30), said two elastic tapes (18) and the edge portions (26) of the support web (20) by a pattern of spot welds (40) while said two elastic tapes (18) are stretched in said transversal direction (Y), and - cutting the support web (20) along at least one continuous undulated cutting line (42) passing through said micro-hook formation (22) so as to form two separate continuous transversely extensible elastic laminates (50), wherein each of said continuous transversely extensible elastic laminates (50) has a respective pleated central portion (12, 32) having pleats (52, 54) parallel to said longitudinal direction (X) and respective first and second non-pleated edge portions (14, 34, 16, 36) on opposite sides of said pleated central portions (12, 32).
  11. A method for producing a continuous transversely extensible elastic laminate (50) comprising: - feeding in a longitudinal direction (X) a first continuous web (10), - feeding in said longitudinal direction (X) two continuous elastic tapes (18) parallel to each other and spaced from each other in a transverse direction (Y) transversal to said longitudinal direction (X), - elastically stretching said two continuous elastic tapes (18) in a transverse direction (Y), and applying said two continuous elastic tapes (18) to respective portions of said first continuous web (10) while stretched in said transversal direction (Y), - feeding a second continuous web (30) of a non-woven material in said longitudinal direction (X), the second continuous web (30) having a micro-hook formation (22) integrally formed in the non-woven material forming said second continuous web (30), - applying said second continuous web (30) to the first continuous web (10) and sandwiching said two continuous elastic tapes (18) between respective portions of said first and second webs (10, 30), - joining to each other said first and second web (10, 30) and said two elastic tapes (18) by a pattern of spot welds (40) while said two elastic tapes (18) are stretched in said transversal direction (Y), - cutting said first and second webs (10, 30) along at least one continuous undulated cutting line (42) passing through said micro-hook formation (22) so as to form two separate continuous transversely extensible elastic laminates (50), wherein each of said continuous transversely extensible elastic laminates (50) has a respective pleated central portion (12, 32) having pleats (52, 54) parallel to said longitudinal direction (X) and respective first and second non-pleated edge portions (14, 34, 16, 36) on opposite sides of said pleated central portions (12, 32).
  12. A method for producing a continuous transversely extensible elastic laminate (50) comprising: - feeding in a longitudinal direction (X) a first continuous web (10) having a central portion (12) and first and second edge portions (14, 16) on opposite sides of the central portion (12), - feeding in said longitudinal direction (X) a continuous elastic tape (18), - elastically stretching said continuous elastic tape (18) in a transverse direction (Y) transversal to said longitudinal direction (X), and applying said continuous elastic tape to the central portion of said first continuous web (10) while stretched in said transversal direction (Y), - feeding in said longitudinal direction (X), a continuous support web (20) of a non-woven material having a micro-hook formation (22) integrally formed in the non-woven material forming said support web (20), - cutting the continuous support web (20) along at least one continuous undulated cutting line (42, 44) passing through said micro-hook formation (22) so as to form two separate tab chains (66) having respective continuous longitudinal edge portions (26) and respective tabs (58) having respective integral micro-hook formations (22), - applying said two continuous longitudinal edge portions (26) of said continuous tab chains (66) to respective first edge portions (14, 16) of said first continuous web (10), - feeding in said longitudinal direction (X) a second continuous web (30) having a central portion (32) and first and second edge portions (34, 36) on opposite sides of the central portion (52), - applying said second continuous web (30) to the first continuous web (10) and sandwiching said continuous elastic tape (18) between respective central portions (12, 32) of said first and second webs (10, 30), and - joining to each other said first and second webs (10, 30), said elastic tape (18) and said two continuous longitudinal edge portions (26) of said continuous tab chains (66) by a pattern of spot welds (40), so as to form a continuous transversely extensible elastic laminate (50), wherein said continuous transversely extensible elastic laminate (50) has a pleated central portion (12, 32) having pleats (52, 54) parallel to said longitudinal direction (X) and first and second non-pleated edge portions (14, 34, 16, 36) on opposite sides of said pleated central portions (12, 32).
  13. The method of claim 10 or 11, wherein said at least one continuous undulated cutting line (42, 44) forms in each of said continuous transversely extensible elastic laminates (50) a row of tabs (58) connected to each other by a respective continuous longitudinal edge portion (26) and spaced apart from each other in said longitudinal direction (X).
  14. The method of any of claims 10, 11, or 12, wherein said micro-hook formation (22) is integrally formed in said non-woven material by locally liquifying or fluidifying the non-woven material and inserting the liquified or fluidified non-woven material into cavities of a molding roller (29).
  15. The method of claim 14, wherein locally liquifying or fluidifying the non-woven material is obtained by subjecting the non-woven material to ultrasonic compression or to thermomechanical compression.

Description

Field of the invention The present invention relates to a transversely extensible continuous elastic laminate. The present invention has been developed with particular reference to the production of disposable absorbent sanitary articles, such as, for example, diapers, training pants, absorbent sanitary products for incontinent adults, etc. A transversely extensible continuous elastic laminate may constitute a semi-finished intermediate product which can be used for supplying machines for manufacturing absorbent sanitary articles. The transversely extensible continuous elastic laminate can be cut transversely to produce elastic side panels for absorbent sanitary articles. Discrete left and right fastening tabs could be already attached externally on the elastic laminate. Embodiments of the present invention also relate to an elastic side panel for absorbent sanitary articles. The present invention also relates to methods for producing transversely extensible continuous elastic laminates. Prior art An absorbent sanitary article wearable as a pant typically has a structure that comprises a rectangular-shaped central body or chassis and at least one pair of elastic side panels which extend laterally from opposite sides of the central body in the front or rear section of the central body. The side panels are provided with fastening tabs, typically comprising micro-hooks pads, which can be releasably attached to a front panel for closing the absorbent sanitary article around the waist of the user. EP-A-3213728 discloses a transversely extensible elastic laminate comprising: a first and a second web, having respective pleated central portions, an elastic tape sandwiched between the pleated central portions of the first and second web and elastically stretchable in a transverse direction, and a plurality of fastening tabs spaced apart from each other in a longitudinal direction. The fastening tabs each include a non-woven support web of soft material and a micro-hook pad of relatively rigid thermoplastic material fixed on a surface of the non-woven support web by glue or by welding. The micro-hook pads are produced starting from continuous tapes, usually made of relatively rigid thermoplastic material, having continuous or intermittent micro-hook formations integrally formed thereon. The continuous tape with integrally formed micro-hook formations is cut to form a plurality of discrete micro-hook pads. Such discrete micro-hook pads are spaced by a desired pitch and are fixed in spaced positions on a surface of a continuous non-woven support web. The continuous non-woven support web with the micro-hook pads fixed thereon is then cut to form fastening tabs each including a non-woven support web of soft material and a micro-hook pad of relatively rigid thermoplastic material fixed on a surface of the non-woven support web by glue or by welding. The continuous tapes with integrally formed micro-hook formations is manufactured by suppliers specialized in manufacturing hook-and-loop fasteners. The micro-hook tapes are packaged in reels which are delivered to the manufacturing plants of absorbent sanitary articles. In the machines for manufacturing absorbent sanitary articles the reels of continuous tapes with integrally formed micro-hook formations are unwound, cut, spaced, and fixed to the continuous non-woven support web. All these operations require complex and expensive dedicated equipment which increase the complexity of the machines for manufacturing absorbent sanitary articles. The cost of the continuous tapes with integrally formed micro-hook formations is high, therefore, the dimensions of the micro-hook pads or patches is kept to the minimum possible, which requires complex equipment for cutting the continuous tapes with integrally formed micro-hook formations in very small pieces and for feeding such small pieces with high precision to the continuous non-woven support web. A further drawback of the prior art is that the micro-hook fastening pads are made of relatively rigid thermoplastic material. The user usually perceives unpleasant stiffness during the application of the sanitary article to the wearer. It is not unusual that the user gets scratches or small cuts on the soft skin under the nails due to the contact with sharp and rigid edges of the micro-hook pads. Object and summary of the invention The object of the present invention is to provide a transversely extensible continuous elastic laminate usable to produce elastic side panels for absorbent sanitary articles, which overcomes the problem of the prior art. According to a first aspect of the invention, this object is achieved by a transversely extensible continuous laminate having the features of claim 1. An important feature of the present invention is that the tabs with micro-hook formations can be manufactured in-line in a machine for manufacturing absorbent sanitary articles starting from reels of non-woven material. Therefore, there is no need