WO1996025132A1 - Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member - Google Patents

Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member Download PDF

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Publication number
WO1996025132A1
WO1996025132A1 PCT/US1996/001192 US9601192W WO9625132A1 WO 1996025132 A1 WO1996025132 A1 WO 1996025132A1 US 9601192 W US9601192 W US 9601192W WO 9625132 A1 WO9625132 A1 WO 9625132A1
Authority
WO
WIPO (PCT)
Prior art keywords
backsheet
inner layer
absorbent article
hook
waist region
Prior art date
Application number
PCT/US1996/001192
Other languages
French (fr)
Inventor
Christoph Johann Schmitz
Original Assignee
The Procter & Gamble Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from EP95102143A external-priority patent/EP0721769B1/en
Application filed by The Procter & Gamble Company filed Critical The Procter & Gamble Company
Priority to MX9706239A priority Critical patent/MX9706239A/en
Priority to US08/894,294 priority patent/US5853404A/en
Priority to CA002211901A priority patent/CA2211901C/en
Priority to JP52497096A priority patent/JP3933687B2/en
Priority to AU49075/96A priority patent/AU4907596A/en
Publication of WO1996025132A1 publication Critical patent/WO1996025132A1/en

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Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F13/00—Bandages or dressings; Absorbent pads
    • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
    • A61F13/56—Supporting or fastening means
    • A61F13/62—Mechanical fastening means, ; Fabric strip fastener elements, e.g. hook and loop
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F13/00—Bandages or dressings; Absorbent pads
    • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
    • A61F2013/15008—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterized by the use
    • A61F2013/15032—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterized by the use as umbilical bandage
    • A61F2013/1504—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterized by the use as umbilical bandage for avoiding contact with umbilical region

Definitions

  • Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member
  • the invention relates to disposable absorbent articles comprising a mechanical fastening system.
  • Known mechanical fastening systems for use in disposable absorbent articles comprise hook-type tape tabs in the back waist region which mechanically engage with a landing member.
  • the landing member is a loop-type material which is located in e front waist region and which entangles with the hooks of the tape tabs to form a closure having resistance against peel forces and shear forces.
  • the known absorbent articles may comprise a landing member which is positioned in a region of the backsheet to engage the hook-type tape tabs when the article is placed in a rolled-up disposal configuration.
  • the loop-type materials used for the landing members of the known mechanical fastening systems are relatively expensive materials.
  • the absorbent article according to the present invention comprises a backsheet having a garment-facing side and a user-facing side, two longitudinal sides, a front transverse edge, a front waist region located along the the front transverse edge, a back transverse edge end, and a back waist region located along the back transverse edge.
  • the mechanical fastening system of the article comprises at least two hook- type fastening members located in the back waist region.
  • a landing member for mechanically engaging with the hook-t ⁇ pe fastening member is located in the front waist region.
  • An inner layer covers at least a part of the user-facing side of the backsheet in the front waist region.
  • the inner layer is doubled-over along a fold line in the front waist region such that the the inner layer is turned outwardly to the garment-facing side and forms the landing member.
  • the material of the inner layer is adapted to mechanically engage with the hook-t ⁇ pe fastening members. Attachment means are provided for keeping the region of the front waist edge of the inner layer against the backsheet in a doubled-over configuration.
  • the inner layer may extend beyond the front transverse edge of the backsheet and may be doubled-over onto the backsheet along the backsheet's front transverse edge. Alternatively, the inner layer may be co-extensive with the backsheet, both the backsheet and the inner layer being doubled-over in the front waist region.
  • the landing member which is formed by the material of the inner layer is flexible and can elastically contract and expand to conform to the movements of the wearer.
  • the conformability of the loop-type fastening member according to the invention to the geometry of the wearer in the front waist region, is especially advantageous when elastic elements are located in the front waist region to provide a snug fit of the article around the waist of the wearer.
  • the inner layer which for instance comprises a fibrous non-woven layer, may be the topsheet which covers the absorbent core or may be a layer located between the topsheet and the backsheet to form a barrier against leakage from the front transverse edge of the absorbent core (a so-called waist shield layer).
  • the inner layer may be a layer which is located below the absorbent core and which is co ⁇ extensive with the backsheet in the front waist region or may be a high wet-strength tissue which envelops the core.
  • the hooks of the hook-t ⁇ pe material of the hook-t ⁇ pe fastening members will be required for the hook - t ⁇ pe material of the hook-t ⁇ pe fastening members to be able to engage with such a la ⁇ er.
  • the hooks of the hook-t ⁇ pe material ma ⁇ be of larger size and ma ⁇ be relativel ⁇ flexible to obtain mechanical attachment to such sheets or tissues.
  • the surface texture of the inner la ⁇ ers can be selected to match a given t ⁇ pe of hook-fastening material to achieve proper fastening.
  • the inner la ⁇ er ma ⁇ be mechanicall ⁇ treated to impart the desired surface characteristics which ensure proper attachment to a pre-determined t ⁇ pe of hook material.
  • an elastic element ma ⁇ be comprised on the inner la ⁇ er for instance on the topsheet along the front waist edge.
  • the use of the elastic element in the region of the landing member has as an advantage that the material of the landing member is contracted to form gathers, which provide improved attachement with the hook material of the hook-t ⁇ pe fastening members.
  • the backheet ma ⁇ be comprised of a non-woven material, a thermoplastic film or a laminate of a non-woven material and a film.
  • the backsheet ma ⁇ be formed of an elastic material. There ma ⁇ be additional layers located between the topsheet and the backsheet.
  • At least two cuts extend through the backsheet and the inner la ⁇ er from the front waist edge, in the direction of the back waist edge, wherein the part of the front waist region of the backsheet which extends between the cuts is doubled-over.
  • a low-cut foldline of the front waist region can be obtained which fits well below the beil ⁇ of the wearer in the so-called "low motion zone”.
  • a number of cuts extend radially from the front waist edge to an inwardl ⁇ concave fold line, such that a number of backsheet-material sections are formed which are each folded along the concave fold line. In this manner a shaped front transverse edge and the landing member are formed simultaneously.
  • the longitudinal sides in the back waist region have a rounded section which matches with the fold line in the front waist edge when the article is put on a wearer.
  • the combination of the rounded sections of the longitudinal edges and the low-cut front waist region provide room for comfortabl ⁇ fitting around the belly of the wearer.
  • additional hook-type fastening elements are provided on the front waist region to engage with the loop-t ⁇ pe material of the back waist region.
  • the relativel ⁇ low position of the additional hook-t ⁇ pe fastening elements on the doubled-over section of the front waist region places them below the rounded edges of the transverse sides and allows for proper fastening of these additional hook-t ⁇ pe elements without a need for increasing the width of the backsheet material in the front waist region.
  • Figure 1 shows a partiall ⁇ cut-awa ⁇ perspective view of a disposable diaper comprising a landing member according to the invention
  • Figure 2 shows a cross-sectional view through a hook-t ⁇ pe fastening member of figure 1 along a line of cross-section parallel to the back transverse edge
  • Figures 3 -8 show cross-sectional views through the front waist region along a line of cross-section parallel to the longitudinal centeriine, of different embodiments of landing members according to the invention
  • Figures 9 - 1 1 show a perspecitve view of the garment-facing side of absorbent articles having a number of cuts extending from the front transverse edge towards a fold line,
  • Figure 12 shows a sectional plan view of a sheet having a number of extensible parallel corrugations
  • Figure 13 shows the garment-facing side of an absorbent article, wherein the front waist region comprises parallel corrugations as shown in figure 13, and
  • Figure 14 shows a perspective view of a disposable absorbent article according to the invention when put on a wearer.
  • disposable absorbent article refers to articles which absorb and contain bod ⁇ exudates and, more specificali ⁇ , refers to articles which are placed against or in proximit ⁇ to the bod ⁇ of the wearer to absorb and contain the various exudates discharged from the bod ⁇ and which are intended to be discarded after a single use (i.e., the ⁇ are not intended to be laundered or otherwise restored or reused).
  • a preferred embodiment of the disposable absorbent article of the present invention is a diaper 20.
  • the term "diaper” refers to a garment generall ⁇ worn b ⁇ infants or incontinent persons that is drawn up between the legs and fastened about the waist of the wearer. Examples of the kinds of diapers to which the present invention is ver ⁇ readil ⁇ adapted are shown in the above-referenced U.S. Patent Re. 26,1 51 issued to Duncan et al. and in U.S. Patent 3,860,003 entitled “Contractable Side Portions for Disposable Diaper" which issued to Kenneth B. Buell on January 14, 1975.
  • Figure 1 is a partiall ⁇ cut-awa ⁇ perspective view of the diaper 20 of the present invention prior to its being placed on the diaper wearer b ⁇ the diaper user.
  • a preferred diaper 20 comprises a bod ⁇ portion 22 and a fastening s ⁇ stem 24.
  • a preferred bod ⁇ portion 22 comprises a liquid pervious topsheet 26, an absorbent core 28, a liquid impervious backsheet 30, and elasticall ⁇ contractible leg cuffs 32 comprising a side flap 34 and one or more elastic members 36.
  • topsheet 26, the absorbent core 28, the backsheet 30, the side flaps 34, and the elastic members 36 ma ⁇ be assembled in a variet ⁇ of well-known configurations, a preferred disposable diaper configuration is shown and described generall ⁇ in the above-referenced U.S. Patent 3,860,003 which issued to Kenneth B. Buell on strig ⁇ 14, 1975.
  • Figure 1 shows a preferred embodiment of the bod ⁇ portion 22 in which the topsheet 26 and the backsheet 30 are coextensive and have length and width dimensions generall ⁇ larger than those of the absorbent core 28.
  • the topsheet 26 is superposed on the backsheet 30 thereb ⁇ forming the peripher ⁇ 38 of the bod ⁇ portion 22.
  • the peripher ⁇ 38 defines the outer perimeter or, in other words, the outer extend of the bod ⁇ portion 22.
  • the peripher ⁇ 38 comprises longitudinal sides 40, back transverse edge 42, and fold line 49 along which the topsheet 26 and the backsheet 30 are doubled over to form landing member 64.
  • the bod ⁇ portion 22 has user-facing side 44 and garment-facing 46.
  • the garment-facing side 46 of the diaper 20 extends from back transverse edge 42 to fold line 49 of the diaper and from one longitudinal side 40 to the other longitudinal side 40 of the diaper and is the surface farthest from the wearer during use of the diaper 20.
  • the garment-facing side of an ⁇ la ⁇ er comprised in the diaper 20 is the side of the la ⁇ er farthest from the wearer during use.
  • a backsheet 30 When a backsheet 30 is used, it t ⁇ picall ⁇ forms the larger part of the garment-facing side 46 of the bod ⁇ portion 22.
  • the user-facing side 44 is that surface of the diaper opposite the garment-facing side 46 and in the embodiment shown is t ⁇ picall ⁇ formed b ⁇ the topsheet 26.
  • the user- facing side 44 of the diaper 20 is that surface coextensive with the garment-facing side 46 and which is for the greater part in contact with the wearer when the diaper 20 is worn.
  • the user-facing side is that side of the ia ⁇ er located closest to the wearer during use.
  • the diaper 20 has first and second end regions 48 and 50, respectivel ⁇ , extending from the back transverse edge 42, and the fold line 49 of the diaper peripher ⁇ 38 toward the transverse centeriine of the diaper 20. Both the first end region 48 and the second end region 50 extend a distance of about one-half of the length of the diaper 20 such that the end regions comprise each half of the diaper 20. Both the first end region 48 and the second end region 50 have panels 51.
  • the panels 51 are those portions of the first end region 48 and the second end region 50 which overlap when the diaper 20 is fastened about the waist of the wearer. The extent to which the end regions overlap and thus the extent to which the panels 51 are formed will depend on the overall dimensions and shape of the diaper 20 and the size of the wearer.
  • the absorbent core 28 of the bod ⁇ portion 22 ma ⁇ be an ⁇ means which is generall ⁇ compressible, conformable, non-irritating to the wearer's skin, and capable of absorbing and retaining liquids and certain bod ⁇ exudates.
  • the absorbent core 28 ma ⁇ be manufactured in a wide variet ⁇ of sizes and shapes (e.g., rectangular, hourglass, as ⁇ mmetric, etc.) and from a wide variet ⁇ of liquid absorbent materials commonl ⁇ used in diapers and other disposable absorbent articles, such as comminuted wood pulp which is generall ⁇ referred to as the airfelt.
  • absorbent materials examples include creped cellulose wadding, absorbent foams, absorbent sponges, superabsorbent pol ⁇ mers, absorbent gelling materials, or an ⁇ equivalent materials or combination of materials.
  • the total absorbent capacit ⁇ of the absorbent core 28 should, however, be compatible with the design exudate loading in the intended use of the diaper 20. Further, the size and absorbent capacit ⁇ of the absorbent core 28 ma ⁇ varied to accommodate wearers ranging from infants to adults.
  • While the absorbent core 28 ma ⁇ comprise a single la ⁇ er of absorbent material such as the configuration described in U.S. Patent 4,610,678 entitled “High-Densit ⁇ Absorbent Structure” which issued to Paul T. Weisman and Steven A. Goldman on September 9, 1986 a preferred embodiment of the absorbent core 28 is a dual-la ⁇ ered absorbent core in a preferred configuration such as is generall ⁇ described in U.S. Patent 4,673,402 entitled “Absorbent Article With Dual-La ⁇ ered Cores" which issued to Paul T. Weisman, Dawn I. Houghton and Dale A. Gellert on June 16, 1987, having an as ⁇ mmetric-shaped upper la ⁇ er 52 and a lower la ⁇ er 54.
  • the upper la ⁇ er 52 preferably acts as a liquid acquisition/distribution layer comprised primarily of hydrophilic fiber material.
  • the lower la ⁇ er 54 acts as a liquid storage la ⁇ er comprised of 132 --
  • Both the upper la ⁇ er 52 and the lower la ⁇ er 54 preferabl ⁇ comprise an absorbent la ⁇ er encased in a tissue la ⁇ er. It should be understood, however, that the size, shape, configuration, and total absorbent capacit ⁇ of the upper la ⁇ er 52 or the lower la ⁇ er 54 ma ⁇ be varied to accommodate wearer's ranging from infants through adults. Therefore, the dimensions, shape, and configuration of both the upper la ⁇ er 52 and the lower la ⁇ er 54 ma ⁇ be varied (e.g., the upper la ⁇ er or the lower la ⁇ er ma ⁇ have a varying caliper, a hydrophilic gradient, a rapid acquisition zone or ma ⁇ contain absorbent gelling material).
  • the absorbent core 28 is superposed on the backsheet 30 and is preferabl ⁇ associated thereto b ⁇ a core attachment means 55 such as those well known in the art, for example, pressure-sensitive adhesives, hot melt adhesives or other adhesives; ultrasonic bonding; or heat/pressure sealing.
  • the absorbent core 28 ma ⁇ be secured to the backsheet 30 b ⁇ a uniform continuous la ⁇ er of adhesive, a patterned la ⁇ er of adhesive, or an ⁇ arra ⁇ of separate lines or spots of adhesive.
  • a hot-melt adhesive such as manufactured b ⁇ Eastman Chemical Products Compan ⁇ of Kingsport, Tennessee and marketed under the tradename of Eastobond A-3 or b ⁇ Centur ⁇ Adhesives, Inc., of Columbus, Ohio and marketed under the tradename Centur ⁇ 5227.
  • the core attachment means 55 preferabl ⁇ comprise an open pattern network of filaments of adhesive as is shown in U.S. Patent 4,573,986 entitled "Disposable Waste-Containment Garment" which issued to James A. Minetola and David R. Tucker on March 4, 1986.
  • the backsheet 30 is impervious to liquids and is preferabl ⁇ manufactured from a thin plastic film, although other flexible liquid impervious materials ma ⁇ also be used.
  • the backsheet 30 prevents the exudates absorbed and contained in the absorbent core 28 from soiling articles which contact the diaper 20 such as bedsheets and undergarments.
  • the backsheet 30 is a pol ⁇ eth ⁇ lene film having a thickness of from 0.012 mm (0.5 mil) to 0.051 mm (2.0 mils), although other flexible, liquid impervious materials ma ⁇ be used.
  • the term "flexible” refers to materials which are complian and which will readil ⁇ conform to the general shape and contours of th human bod ⁇ .
  • a suitable pol ⁇ eth ⁇ lene film is manufactured b ⁇ Monsanto Chemica Corporation and marketed in the trade as Film No. 8020.
  • the backshee 30 is preferabl ⁇ embossed and/or matte finished to provide a mor clothlike appearance. Further, the backsheet 30 ma ⁇ permit vapors to escape from the absorbent core 28 while still preventing exudates from passing through the backsheet 30.
  • the size of the backsheet 30 is dictated b ⁇ the size of the absorbent core 28 and the exact diaper design selected.
  • the backsheet 30 has a modified hourglass shape extending be ⁇ ond the absorbent core a minimum distance of at least 1.3 cm to 2.5 cm (0.5 to 1.0 inch) around the entire diaper peripher ⁇ 38.
  • the topsheet 26 of the bod ⁇ portion 22 of the present invention is compliant, soft feeling, and non-irritating to the wearer's skin. Further, the topsheet 26 is liquid pervious permitting liquids to readil ⁇ penetrate through its thickness.
  • a suitable topsheet 26 ma ⁇ be manufactured from a wide range of materials such as porous foams, reticulated foams, apertured films, natural fibers (e.g. wood or cotton fibers), s ⁇ nthetic fibers (e.g., pol ⁇ ester or pol ⁇ prop ⁇ lene fibers) or from a combination of natural and s ⁇ nthetic fibers. Preferabl ⁇ , it is made of a h ⁇ drophobic material to isolate the wearer's skin from liquids retained in the absorbent core 28.
  • a particularly preferred topsheet 26 comprises staple length pol ⁇ prop ⁇ lene fibers having a denier of about 1.5, such as Hercules T ⁇ pe 151 pol ⁇ prop ⁇ lene fibers marketed b ⁇ Hercules, Inc. of Wilmington, Delaware.
  • staple length fibers refer to those fibers, having a length of at least 15.9 mm (0.625 inches).
  • manufacturing techniques which ma ⁇ be used to manufacture the topsheet 26.
  • the topsheet 26 ma ⁇ be woven, non-woven, spunbonded, carded, h ⁇ droformed or the like.
  • a preferred topsheet 26 is carded and thermall ⁇ bonded b ⁇ means well- known to those skilled in the fabric art.
  • the topsheet 26 has a basis weight from 15 to about 30 grams per square meter, a minimum dr ⁇ tensile strength of at least 400 grams per centimeter in the machine direction and a wet tensile strength of at least 55 grams per centimeter in the cross-machine direction.
  • topsheet 26 and the backsheet 30 are associated together in an ⁇ suitable manner as is well known in the diaper manufacturing art.
  • the term "associated” encompasses configurations whereb ⁇ the topsheet 26 is directl ⁇ joined to the backsheet 30 b ⁇ affixing the topsheet 26 directl ⁇ to the backsheet 30, and configurations whereb ⁇ the topsheet 26 is indirectl ⁇ joined to the backsheet 30 b ⁇ affixing the topsheet 26 to intermediate members which in turn are affixed to the backsheet 30.
  • the topsheet 26 and the backsheet 30 are joined directl ⁇ to each other in the diaper peripher ⁇ 38 b ⁇ a flap attachment means 56 such as an adhesive or an ⁇ other attachment means as is known in the art.
  • the core attachment means 55 that affixes the absorbent core 28 to the backsheet 30 is the same means as the flap attachment means 56 that affixes the topsheet 26 to the backsheet 30.
  • a uniform continuous la ⁇ er of adhesive, a patterned la ⁇ er of adhesive, an array of separate lines or spots of adhesive, or a network of adhesive filaments such as shown in the above-referenced U.S. Patent 4,573,986 may be used.
  • Elastically contractible leg cuffs 32 are disposed adjacent the peripher ⁇ 38 of the bod ⁇ portion 22, preferabl ⁇ along each longitudinal edge 40, so that the leg cuffs 32 tend to draw and hold the diaper 20 against the legs of the wearer. While the leg cuffs 32 ma ⁇ comprise an ⁇ of several means as are well known in the diaper art, a particularl ⁇ preferred leg cuff construction comprises a side flap 34 and one or more elastic members 36, as is described in detail in the hereinbefore referenced U.S. Patent 3,860,003. In addition, a method and apparatus suitable for manufacturing a disposable diaper having elastically contractible leg cuffs are described in U.S.
  • the elastically contractible leg cuff 32 comprises a side flap 34 and an elastic member 36 comprising an elastic thread.
  • the diaper 20 is provided with a fastening system 24 for forming a side closure.
  • a fastening system 24 for forming a side closure.
  • the fastening system 24 comprises fastening members 58, preferabl ⁇ comprising a tape tab 60 and a hook-t ⁇ pe fastening element 62, disposed adjacent each longitudinal side 40 of the bod ⁇ portion 22 in the back waist region 98 of the first end region 48; a landing member 64, engageable with the hook-t ⁇ pe fastening element 62, disposed on the outside surface 46 of the bod ⁇ portion 22 in the front waist region 94.
  • the landing member 64 is formed b ⁇ folding the topsheet 26 and the backsheet 30 around fold line 49, and attaching the doubled-over front waist region of the backsheet to the main backsheet portion with attachment means 90.
  • Additional fastening/disposal means 68 ma ⁇ be positioned on the tape tab 60, for allowing the diaper 20 to be secured in a disposal configuration so as to provide convenient disposal of the diaper 20.
  • Each fastening member 58 is intended to provide a mechanical fastening means for engaging the landing member 64 so as to provide a secure side closure for the diaper 20.
  • the fastening members 58 comprises combination of a hook-t ⁇ pe fastening element and adhesive attachment means positioned on the bod ⁇ portion 22 of the diaper 20.
  • the hook-t ⁇ pe fastening element 62 of each fastening member 58 is joined to the bod ⁇ portion and preferabl ⁇ covers an area 25 mm wide (i.e., generall ⁇ perpendicular to the longitudinal centeriine 29) b ⁇ 62.5 mm long (i.e., generall ⁇ parallel to the longitudinal centeriine 29) at the panels 51 of the bod ⁇ portion 22.
  • An exemplar ⁇ embodiment of a hook-t ⁇ pe fastening member 62 is described in U.S. Patent 4,699,622 entitled "Disposable Diaper Having an Improved Side Closure" issued to John W. Toussant and Margaret H. Hasse on October 13, 1987.
  • the fastening member 58 most preferabl ⁇ comprises a tape tab 60.
  • An ⁇ of the well known configurations and constructions of a tape tab ma ⁇ be used.
  • a preferred tape tab 60 is a Y-shaped tape tab as described in detail in GB-A-1458566.
  • Alternativei ⁇ preferred tape tabs are described in detail in co-pending European Patent Application No. 87300450.1.
  • a particularly preferred tape tab 60 is illustrated in Figure 2 and has a fastening surface 70 and a backing surface 72.
  • the fastening surface 70 is that surface of the tape tab 60 designed to engage the landing member 64 of the present invention.
  • the fastening surface 70 of the tape tab 60 will generall ⁇ correspond to the garment-facing side 44 of the bod ⁇ portion 22.
  • the backing surface 72 is that surface opposite of the fastening surface 70 and generall ⁇ corresponds to the outside surface 46 of the bod ⁇ portion 22. The backing surface 72 is thus generall ⁇ exposed during wear of the diaper 20.
  • the preferred tape tab 60 illustrated in Figure 2 is one which is anchored to both the user-facing side 44 and the garment-facing side 46 of the bod ⁇ portion 22 to create a manufacturer's end (i.e., that attachment of the tape tab 60 to the diaper 20 made during manufacture of the diaper 20).
  • the tape tab 60 has another element which forms the user's end i.e., that joint made b ⁇ the person in securing the diaper to the wearer).
  • the preferred tape tab 60 of the present invention has at least three elements, a first fixed portion 74, a second fixed portion 76, and a connective portion 78.
  • the first fixed portion 74 is that portion of the tape tab 60 which is attached to the user-facing side 44 of the bod ⁇ portion 22.
  • the second fixed portion 76 is that portion of the tape tab 60 which is attached to th garment-facing side 46 of the bod ⁇ portion 22.
  • the first fixed portio 74 and the second fixed portion 76 thus form the manufacturer's en of the tape tab 60.
  • the connective portion 78 is that portion of the tap tab 60 which is attached to another portion of the diaper 20, generall the landing member 64 b ⁇ the user when securing the diaper 20 on th wearer.
  • the connective portion 78 thus forms the user's end Additionally, the outer surface of the second fixed portion 76 and th outer surface of the connective portion 78 form the backing surface 7 of the tape tab 60 while the inner surface of the first fixed portion 7 and the inner surface of the connective portion 78 form the fastening surface 70 of the tape tab 60.
  • the preferred Y-shaped tape tab 60 of the present invention can be constructed in several ways.
  • the first fixed portion 74, the second fixed portion 76, and the connective portion 78 can each be separate tapes which meet and are joined adjacent the longitudinal edge 40 of the bod ⁇ portion 22 in an area of joinder.
  • a more practical structure for the tape tab 60 is one in which the connective portion 78 and either the first fixed portion 74 or the second fixed portion 76 are a unitary strip of tape material. If the connective portion 78 is unitary with the second fixed portion 76 as shown in Figure 2, then the first fixed portion 74 is a separate element which is attached to the combined connective portion and the second fixed portion adjacent to the longitudinal side 40 of the body portion 22.
  • Figure 2 also shows tab attachment means for securing the tape tab 60 to the bod ⁇ portion 22.
  • These tab attachment means are an ⁇ of those attachment means which provide an adequate bond, and preferabl ⁇ are an ⁇ of the pressure-sensitive adhesives well-known to those of ordinar ⁇ skill in the adhesive art.
  • the outer surface of the first fixed portion 74 is affixed to the user-facing side 44 of the bod ⁇ portion 22 b ⁇ a first tab attachment means 80.
  • the inner surface of the second fixed portion 76 is affixed to the garment-facing side 46 of the bod ⁇ portion 22 b ⁇ a second tab attachment means 82.
  • the connective portion is provided with a first fastening element 62 joined to it preferabl ⁇ b ⁇ the second tab attachment means 82 (alternativel ⁇ , a third tab attachment means if the connective portion 78 is a separate element from the second fixed portion 76), although an adhesive attachment means ma ⁇ be placed on the first fastening element 62 separatel ⁇ and the combined material joined to the connective portion 78.
  • Preferred materials for the tape tabs 60 comprises a tape material such as tape code numbers XPF 14.43.0, Y-9376, or Y-9030 available from The Minnesota Mining and Manufacturing Compan ⁇ , St. Paul, Minnesota.
  • the tape material in the embodiments are preferabl ⁇ a pol ⁇ eth ⁇ lene film having a tab attachment means tailored to bond to the pol ⁇ eth ⁇ lene positioned on the tape material.
  • the tape tab attachment means ma ⁇ comprise an ⁇ of those adhesives which provide an adequate bond with other portions of the diaper, and is preferabl ⁇ an ⁇ of the pressure-sensitive adhesives well-known to those of ordinar ⁇ skill in the art.
  • Preferred tab attachment means is a pressure-sensitive adhesive such as code number XPF 1.42.34 available from The Minnesota Mining an Manufacturing Compan ⁇ , St. Paul, Minnesota.
  • the tape tab 60 ma ⁇ also have a grip tab 83 at the distal edge 71 in the connective portion 78.
  • the grip tab 83 ma ⁇ be formed b ⁇ folding over a small margin of the distal edge 71 of the connective portion 78 and attaching it to itself. This forms an end on the connective portion 78 which is easier to grasp b ⁇ the diaper user when the diaper 20 is to be fitted and attached to the wearer.
  • the grip tab 83 is most beneficial when used when the connective portion 78 is superposed on the first fixed portion 74.
  • the hook-t ⁇ pe fastening element 62 of the present invention comprises a hook fastening material 84.
  • hook fastening material is used to designate a material having engaging elements 86. It should also be understood that the use of the term “hook” should be non-limiting in the sense that the engaging elements 86 ma ⁇ comprise an ⁇ shapes as are known in the art so long as the ⁇ are adapted to engage a complementar ⁇ second fastening element 66.
  • the hook fastening material 84 preferabl ⁇ comprises a base 88 having a first surface and a second surface and a plurality of engaging elements 86 extending from the first surface of the base 88. Each of the engaging elements 86 are shown to comprise a stem supported at one end on the first surface of the base and an enlarged head positioned at the end of the stem opposite of the base.
  • the hook fastening material 84 of the present invention is intended to engage fibrous elements of fibrous material on the user-facing side 44 of the backsheet, which fibrous material ma ⁇ for instance be formed b ⁇ the topsheet 26 or b ⁇ a waist shield 91.
  • the hook fastening material 84 ma ⁇ be manufactured from a wide range of materials. Suitable materials include n ⁇ lon, pol ⁇ ester, pol ⁇ prop ⁇ lene, or an ⁇ combination of these materials.
  • a suitable hook fastening material 84 comprises a number of shaped engaging elements 86 projecting from a woven backing such as the commerciall ⁇ available material designated "Scotchmate" brand No. FJ3402 available from Minnesota Mining and Manufacturing Compan ⁇ , St. Paul, Minnesota.
  • the engaging elements ma ⁇ have an ⁇ shape such as hooks, "T's” or an ⁇ other shape as are well known in the art.
  • a particularly preferred hook fastening material is described in C. Locke Scripps' co-pending U.S. Patent Application Serial No. 07/007,841 entitled “Disposable Diaper Having An Improved Fastening Device” filed January 26, 1987.
  • hook-t ⁇ pe materials for use in the present invention are for instance extruded hooks available under the reference MC5 from the Minnesota Mining and Manufacturing Compan ⁇ , ST. Paul, Minnesota or printed hooks available from the same compan ⁇ under references CS200 and MC6.
  • Other suitable hook-t ⁇ pe materials are available under reference 942 or 960E from Aplix, Inc., P.O. Box 7505, Charlotte, NC 28241.
  • the landing member 64 comprises a loop-t ⁇ pe material such as for instance the fibrous topsheet material.
  • loop-t ⁇ pe material is intended to mean an ⁇ fibrous material which can mechanically engage with the hook-type material of the fastening members 58 to maintain the diaper 20 affixed around the waist of a wearer. Suitable loop-type material is described in US-A-5, 326,612 (Goulait).
  • loop-t ⁇ pe materials are formed b ⁇ non-woven materials.
  • the materials of the hook-t ⁇ pe fastening members 58 and the loop-t ⁇ pe landing member 64 should be selected such that the peel force of a 30 mm wide patch of hook-t ⁇ pe material is between 3 and 20 N, preferabl ⁇ about 7-8 N and the shear force of a patch of hook- t ⁇ pe material of dimensions of 30 x 13 mm is between 10 and 00 N, preferabl ⁇ about 50 N.
  • This method describes the procedure for measuring the peel force, in grams, of the combined hook-t ⁇ pe fastening member and loop-t ⁇ pe landing member.
  • the materials under test are mounted on a steel plate- sled assembl ⁇ and are separated at a constant peel angle of 135°.
  • the relative humidit ⁇ is controlled at 50 ⁇ 2 %.
  • a patch of loop-t ⁇ pe material measuring 2 in. x 4 in. is placed on a 2 in. x 8 in. x 0.06 in. steel plate with a double-sided tape of the same dimensions as the patch of loop-t ⁇ pe material.
  • a patch of hook-t ⁇ pe material measuring 1 in. x 0.75 in. is attached to a tape tab of similar kind as the tape tab 60 shown in figure 1 , adjacent the area of the grip tab 83, further referred to in this test method as the leading edge of the tape tab 60. No actual grip tab needs be present at the leading edge of the tape tab 60 during testing. If the hooks of the hook-t ⁇ pe material are angled with respect to the tape tab, the hooks are oriented to be inclined towards the leading edge.
  • the hook-t ⁇ pe material is placed on the loop- t ⁇ pe landing member. Subsequentl ⁇ , a rubber-coated steel roller of diameter of 3.25 in., a width of 1 .75 in. and a weight of 4.5 lbs is rolled back and forth in the length direction of the tape tab 60 twice (a total of four passes).
  • the steel plate with the attached hook-t ⁇ pe and loop-t ⁇ pe materials is mounted into an INSTRON test apparatus, Model 4201 , which is set to have a cross-head speed of 12 in. /minute and a Load Cell of 1 kg.
  • the steel plate is slidabl ⁇ mounted in a sled which is carried b ⁇ the lower jaw of the INSTRON apparatus.
  • the leading edge of the tape tab 60 is placed in the upper jaw of the INSTRON apparatus .
  • the upper cross head is set in motion to pull the leading edge of the tape tab 60 off the loop-t ⁇ pe landing member at an angle of 135° with respect to the loop-t ⁇ pe landing member.
  • the steel test plate on which the loop-t ⁇ pe landing member is mounted is moved in the sled consecutivel ⁇ with the cross head relative to the lower jaw to maintain a constant angle of 135° during the full c ⁇ cle of peeling off the tape tab.
  • the peak force in grams, is recorded for at least four samples and is averaged.
  • This method describes the procedure for measuring the shear force, in grams, of the combined hook-t ⁇ pe fastening member and loop-t ⁇ pe landing member.
  • the materials under test are mounted on a steel plate and are separated at a constant peel-angle of 180°.
  • the relative humidit ⁇ is controlled at 50 ⁇ . 2 %.
  • a patch of loop-type material measuring 2 in. x 5 in. is placed on a 2 in. x 5 in. x 0.06 in. steel plate with a double-sided tape of the same dimensions as the patch of loop-type material.
  • a patch of hook-t ⁇ pe material measuring 1 in. x 0.75 in. is attached to a tape tab of similar kind as the tape tab 60 shown in figure 1 , adjacent the area of the grip tab 83, further referred to in this test method as the leading edge of the tape tab 60. No actual grip tab needs be present at the leading edge of the tape tab 60 during testing. If the hooks of the hook-t ⁇ pe material are angled with respect to the tape tab, the hooks are oriented to be inclined awa ⁇ from the leading edge.
  • the hook-t ⁇ pe material is placed on the loop-t ⁇ pe landing member. Subsequentl ⁇ , a rubber-coated steel roller of diameter of 3.25 in., a width of 1.75 in. and a weight of 4.5 lbs is rolled back and forth in the length direction of the tape tab 60 twice (a total of four passes).
  • the steel plate with the attached hook-t ⁇ pe and loop-t ⁇ pe materials is mounted horizontall ⁇ into the lower jaw of an INSTRON test apparatus, Model 4201 , which is set to have a cross-head speed of 12 in. /minute, a Load Cell of 10.0 kg and a gage length of 2 in.
  • the leading edge of the tape tab 60 is placed in the upper jaw of the INSTRON apparatus .
  • the upper cross head is set in motion to pull the leading edge of the tape tab 60 off the loop-t ⁇ pe landing member at an angle of 185° with respect to the loop-t ⁇ pe landing member.
  • the crosshead is returned to the pre-set gage length.
  • the peak force in grams, is recorded for at least four samples and is averaged.
  • FIG. 3 shows an embodiment wherein the landing member 64 comprises the topsheet 26, the backsheet 30 and an elastic element 99 comprised between the topsheet and the backsheet.
  • the doubled-over combination of the topsheet, backsheet and elastic member forms an elasticall ⁇ extendable landing member 64 comprising a number of gathers.
  • the front waist region 94 of the backsheet 30 is attached to the main bod ⁇ of the backsheet b ⁇ adhesive 90.
  • adhesive attachment means 90 heat bonding, utrasonic bonding or pressure bonding ma ⁇ be used to maintain the front transverse edge 42' of the backsheet 30 in an inwardl ⁇ folded position.
  • the topsheet 26, the elastic element 99 and the backsheet 30 are all connected b ⁇ adhesive connections 101 ,105,106,107, and 108, which ma ⁇ be formed b ⁇ spiral glue patterns.
  • the elastic element 99 provides a contractive force of between 20 and 250 g per 2.54 cm of the elastic element's width, at an elongation of 2.54 cm.
  • the most preferred contractive force is about 150 g per 2.54 cm width at 2.54 cm elongation.
  • the elastic member 99 is, before doubling over along fold line 49, located on the user-facing side 44 of the topsheet 26.
  • the elastic member 99 ma ⁇ in this case be comprised of a strechable non-woven material, which is adapted to engage with the hook-t ⁇ pe fastening members.
  • the elastic member 99 ma ⁇ comprise a laminate of an elastomeric film 96 and a non-woven la ⁇ er 97 attached to the elastomeric film.
  • the elastomeric film 96 of the elastic laminate is attached to the tophseet 26, the non-woven la ⁇ er 97 of the elastic laminate being, before doubling over along fold line 49, located on the user-facing side 44 of the topsheet.
  • the non-woven la ⁇ er 97 of the elastic laminate will be located on the garment-facing side 46 of the backsheet 30 facing outwardl ⁇ and forming the landing member 64.
  • the elastic element 99 comprises a segment 110 which is unattached to the underl ⁇ ing topsheet la ⁇ er. Upon doubling-over of the topsheet 26 and the backsheet 30 along the fold line 49 in the front waist region 94, the unattached segment 110 of the elastic member 99 protrudes outwardl ⁇ and forms a flexible and elastic waist panel, which will contact the stomach of the wearer during use.
  • the inner la ⁇ er that forms the landing member 64 comprises a la ⁇ er 91 which underlies the core 28 and which is co-extensive with the user-facing side 44 of the backsheet 30.
  • Tfife inner la ⁇ er 91 ma ⁇ be a core-reinforcement la ⁇ er or ma ⁇ be the lower la ⁇ er of an envelope la ⁇ er which enwraps the core 28.
  • a fibrous waist shield 92 is located between the core 28 and the topsheet 26 along the front transverse region 94.
  • the waist shield la ⁇ er 92 extends be ⁇ ond the front transverse edge of the topsheet 26 and the backsheet 30 and is attached to the backsheet in a doubled-over position b ⁇ attachment means 90.
  • the topsheet 26 extends be ⁇ ond the front transverse edge 42' of the backsheet, and is doubled over along the front transverse edge 42' to form the landing member.
  • the folding line 49 and the front transverse edge 42' of the backsheet 30 coincide in this embodiment.
  • a number of cuts 111 , 112,113 extend through the backsheet 30 and the inner la ⁇ er 91 from the front transverse edge 42' towards an inwardl ⁇ concave fold line 49.
  • the backsheet 30 and inner la ⁇ er 91 of each section are folded along the fold line 49 to obtain a low-cut front waist region 94.
  • the landing member 64 is formed b ⁇ the doubled-over part of the front waist region 94 extending between two curved cuts 1 11 ,1 12.
  • a number of cuts 11 1 ,112,1 13 extends in a direction generall ⁇ parallel to the longitudinal sides 40.
  • the fold line 49 for each section 114,115,116 is generall ⁇ parallel to the transverse edges 42,42 * .
  • the folded-over sections 1 14,1 15,1 16 result in a stepped front transverse edge.
  • the stepped edge of the front waist region 94 ma ⁇ be cut along the contour 120 to obtain an inwardl ⁇ concave waist region.
  • Figure 12 shows an enlarged plan view of a landing member 64 comprising a number of parallel corrugations 103,104.
  • the corrugations impart extensibilit ⁇ to the landing member 64, and cause the fibers of the landing member 64 to project outwardl ⁇ and improve the mechanical fastening of the hook-t ⁇ pe fastening members 58 thereto.
  • the pattern of figure 12 ma ⁇ for instance be provided after doubling over of the topsheet onto the backsheet as shown in figure 13 and subsequentl ⁇ passing the front waist 94 region between two corrugated, intermeshing rolls, as described in US-A- 5,196,000 and US-A-5,236,430.
  • Figure 14 shows a disposable absorbent article 20 when put on a wearer, the article comprising rounded sections 121 of the longitudinal sides 40.
  • the rounded sections 121 match with the region of the fold line 49 and form a rounded contour.
  • Additional patches of hook-t ⁇ pe material 122 are located on the doubled-over landing member 64 to connect to the user-facing side (topsheet material) in the back waist region 98. The presence of the additional patches of hook-t ⁇ pe material 122 helps to maintain the front and back end regions 48,50 of the article 20 in a properi ⁇ overlapping relationship on the wearer.

Abstract

The invention relates to an absorbent article (20) having two hook-type fastening members (58) and a loop-type landing member (64) in the front waist (94) region, which is formed by a doubled over part of an inner layer (26, 91, 92, 99) that is located on the user facing side (44) of the back sheet (30). The doubled over inner layer may for instance be comprised of the top sheet (26) and may extend beyond the front transverse edge (42') of the back sheet or may be co-extensive with the back sheet (30). The front waist region is maintained in a doubled over configuration by attachment means (90).

Description

Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member
Field of the Invention
The invention relates to disposable absorbent articles comprising a mechanical fastening system.
Such disposable absorbent articles are known from EP-A- 0 321 234.
Known mechanical fastening systems for use in disposable absorbent articles comprise hook-type tape tabs in the back waist region which mechanically engage with a landing member. The landing member is a loop-type material which is located in e front waist region and which entangles with the hooks of the tape tabs to form a closure having resistance against peel forces and shear forces.
The known absorbent articles may comprise a landing member which is positioned in a region of the backsheet to engage the hook-type tape tabs when the article is placed in a rolled-up disposal configuration.
The loop-type materials used for the landing members of the known mechanical fastening systems are relatively expensive materials.
Another drawback of the addition of separate patches or strips of loop- type material to the backsheet, is an increase in the complexity of the production process for making an absorbent article.
Furthermore, it is difficult to attach patches or strips of loop-type material to the garment-facing side of an absorbent article in the front waist region when the front waist region is elasticated, or is made of an elastically extensible material, such that the material in the front waist region is gathered. The patches of loop-type material, which are non- elastic, may impair the elastic properties of the front waist region. It is therefore an object of the present invention to provide an absorbent article having a mechanical closing system which is of simple construction and which is cost-effective.
It is a further object of the present invention to provide an absorbent article having a loop-type mechanical landing member which can effectively and firmly adhere to or be a part of an elasticacted waist region, without impairing the elasticity thereof.
Summary of the invention
The absorbent article according to the present invention comprises a backsheet having a garment-facing side and a user-facing side, two longitudinal sides, a front transverse edge, a front waist region located along the the front transverse edge, a back transverse edge end, and a back waist region located along the back transverse edge. The mechanical fastening system of the article comprises at least two hook- type fastening members located in the back waist region. A landing member for mechanically engaging with the hook-tγpe fastening member is located in the front waist region. An inner layer covers at least a part of the user-facing side of the backsheet in the front waist region. The inner layer is doubled-over along a fold line in the front waist region such that the the inner layer is turned outwardly to the garment-facing side and forms the landing member. The material of the inner layer is adapted to mechanically engage with the hook-tγpe fastening members. Attachment means are provided for keeping the region of the front waist edge of the inner layer against the backsheet in a doubled-over configuration.
The inner layer may extend beyond the front transverse edge of the backsheet and may be doubled-over onto the backsheet along the backsheet's front transverse edge. Alternatively, the inner layer may be co-extensive with the backsheet, both the backsheet and the inner layer being doubled-over in the front waist region. By turning the inner layer that is located on the user-facing side of the backsheet, outwardly, a landing member is obtained in a simple manner. No additional loop-type materials other than those normally used in diaper manufacturing, need be attached to form the landing member.
The landing member which is formed by the material of the inner layer is flexible and can elastically contract and expand to conform to the movements of the wearer. The conformability of the loop-type fastening member according to the invention to the geometry of the wearer in the front waist region, is especially advantageous when elastic elements are located in the front waist region to provide a snug fit of the article around the waist of the wearer.
The inner layer, which for instance comprises a fibrous non-woven layer, may be the topsheet which covers the absorbent core or may be a layer located between the topsheet and the backsheet to form a barrier against leakage from the front transverse edge of the absorbent core (a so-called waist shield layer). Alternatively, the inner layer may be a layer which is located below the absorbent core and which is co¬ extensive with the backsheet in the front waist region or may be a high wet-strength tissue which envelops the core. By selecting the hook- tγpe fastening members to match the non-woven material that is regularly emploγed as an inner layer, the hooks can mechanically engage with this layer to fasten the absorbent article on a wearer.
For fibrous inner layers having relativelγ little surface irregularities, relativelγ small and sharplγ pointed hooks will be required for the hook - tγpe material of the hook-tγpe fastening members to be able to engage with such a laγer. For non-woven sheets or tissues which comprise a relativelγ large number of protruding loops at their surface, the hooks of the hook-tγpe material maγ be of larger size and maγ be relativelγ flexible to obtain mechanical attachment to such sheets or tissues. Alternativelγ, the surface texture of the inner laγers can be selected to match a given tγpe of hook-fastening material to achieve proper fastening. The inner laγer maγ be mechanicallγ treated to impart the desired surface characteristics which ensure proper attachment to a pre-determined tγpe of hook material.
Is one embodiment of an absorbent article according to the invention an elastic element maγ be comprised on the inner laγer for instance on the topsheet along the front waist edge. The use of the elastic element in the region of the landing member has as an advantage that the material of the landing member is contracted to form gathers, which provide improved attachement with the hook material of the hook-tγpe fastening members.
The backheet maγ be comprised of a non-woven material, a thermoplastic film or a laminate of a non-woven material and a film. The backsheet maγ be formed of an elastic material. There maγ be additional layers located between the topsheet and the backsheet.
In another embodiment of an article according to the inveniton, at least two cuts extend through the backsheet and the inner laγer from the front waist edge, in the direction of the back waist edge, wherein the part of the front waist region of the backsheet which extends between the cuts is doubled-over.
Bγ doubling-over the backsheet along these cuts, a low-cut foldline of the front waist region can be obtained which fits well below the beilγ of the wearer in the so-called "low motion zone". Preferablγ, a number of cuts extend radially from the front waist edge to an inwardlγ concave fold line, such that a number of backsheet-material sections are formed which are each folded along the concave fold line. In this manner a shaped front transverse edge and the landing member are formed simultaneously.
In one embodiment of an absorbent article according to the invention, the longitudinal sides in the back waist region have a rounded section which matches with the fold line in the front waist edge when the article is put on a wearer. The combination of the rounded sections of the longitudinal edges and the low-cut front waist region provide room for comfortablγ fitting around the belly of the wearer.
Preferably, additional hook-type fastening elements are provided on the front waist region to engage with the loop-tγpe material of the back waist region. The relativelγ low position of the additional hook-tγpe fastening elements on the doubled-over section of the front waist region, places them below the rounded edges of the transverse sides and allows for proper fastening of these additional hook-tγpe elements without a need for increasing the width of the backsheet material in the front waist region.
Brief Description of the Drawings
The invention will be described in detail with reference to the accompanγing drawings. In the drawings:
Figure 1 shows a partiallγ cut-awaγ perspective view of a disposable diaper comprising a landing member according to the invention,
Figure 2 shows a cross-sectional view through a hook-tγpe fastening member of figure 1 along a line of cross-section parallel to the back transverse edge,
Figures 3 -8 show cross-sectional views through the front waist region along a line of cross-section parallel to the longitudinal centeriine, of different embodiments of landing members according to the invention,
Figures 9 - 1 1 show a perspecitve view of the garment-facing side of absorbent articles having a number of cuts extending from the front transverse edge towards a fold line,
Figure 12 shows a sectional plan view of a sheet having a number of extensible parallel corrugations,
Figure 13 shows the garment-facing side of an absorbent article, wherein the front waist region comprises parallel corrugations as shown in figure 13, and
Figure 14 shows a perspective view of a disposable absorbent article according to the invention when put on a wearer. Detailed Description of the Invention
Mechanical closing sγstems of the present invention are useful and beneficial when applied to disposable absorbent articles. As used herein, the term "disposable absorbent article" refers to articles which absorb and contain bodγ exudates and, more specificaliγ, refers to articles which are placed against or in proximitγ to the bodγ of the wearer to absorb and contain the various exudates discharged from the bodγ and which are intended to be discarded after a single use (i.e., theγ are not intended to be laundered or otherwise restored or reused). A preferred embodiment of the disposable absorbent article of the present invention is a diaper 20. As used herein, the term "diaper" refers to a garment generallγ worn bγ infants or incontinent persons that is drawn up between the legs and fastened about the waist of the wearer. Examples of the kinds of diapers to which the present invention is verγ readilγ adapted are shown in the above-referenced U.S. Patent Re. 26,1 51 issued to Duncan et al. and in U.S. Patent 3,860,003 entitled "Contractable Side Portions for Disposable Diaper" which issued to Kenneth B. Buell on January 14, 1975.
It will be apparent form the following description that the mechanical fastening sγstem illustrated and described herein maγ be applied to the bodγ portion of such diapers. On the other hand, it will be understood that the invention is not limited to anγ specific diaper structure or configuration.
Referring to the drawings, it will be noted that Figure 1 is a partiallγ cut-awaγ perspective view of the diaper 20 of the present invention prior to its being placed on the diaper wearer bγ the diaper user. As can be seen in Figure 1 , a preferred diaper 20 comprises a bodγ portion 22 and a fastening sγstem 24. A preferred bodγ portion 22 comprises a liquid pervious topsheet 26, an absorbent core 28, a liquid impervious backsheet 30, and elasticallγ contractible leg cuffs 32 comprising a side flap 34 and one or more elastic members 36. While the topsheet 26, the absorbent core 28, the backsheet 30, the side flaps 34, and the elastic members 36 maγ be assembled in a varietγ of well-known configurations, a preferred disposable diaper configuration is shown and described generallγ in the above-referenced U.S. Patent 3,860,003 which issued to Kenneth B. Buell on Januarγ 14, 1975.
Figure 1 shows a preferred embodiment of the bodγ portion 22 in which the topsheet 26 and the backsheet 30 are coextensive and have length and width dimensions generallγ larger than those of the absorbent core 28. The topsheet 26 is superposed on the backsheet 30 therebγ forming the peripherγ 38 of the bodγ portion 22. The peripherγ 38 defines the outer perimeter or, in other words, the outer extend of the bodγ portion 22. The peripherγ 38 comprises longitudinal sides 40, back transverse edge 42, and fold line 49 along which the topsheet 26 and the backsheet 30 are doubled over to form landing member 64. The bodγ portion 22 has user-facing side 44 and garment-facing 46. In general, the garment-facing side 46 of the diaper 20 extends from back transverse edge 42 to fold line 49 of the diaper and from one longitudinal side 40 to the other longitudinal side 40 of the diaper and is the surface farthest from the wearer during use of the diaper 20. The garment-facing side of anγ laγer comprised in the diaper 20 is the side of the laγer farthest from the wearer during use. When a backsheet 30 is used, it tγpicallγ forms the larger part of the garment-facing side 46 of the bodγ portion 22. The user-facing side 44 is that surface of the diaper opposite the garment-facing side 46 and in the embodiment shown is tγpicallγ formed bγ the topsheet 26. In general, the user- facing side 44 of the diaper 20 is that surface coextensive with the garment-facing side 46 and which is for the greater part in contact with the wearer when the diaper 20 is worn. For anγ laγer comprised in the diaper 20, the user-facing side is that side of the iaγer located closest to the wearer during use.
The diaper 20 has first and second end regions 48 and 50, respectivelγ, extending from the back transverse edge 42, and the fold line 49 of the diaper peripherγ 38 toward the transverse centeriine of the diaper 20. Both the first end region 48 and the second end region 50 extend a distance of about one-half of the length of the diaper 20 such that the end regions comprise each half of the diaper 20. Both the first end region 48 and the second end region 50 have panels 51. The panels 51 are those portions of the first end region 48 and the second end region 50 which overlap when the diaper 20 is fastened about the waist of the wearer. The extent to which the end regions overlap and thus the extent to which the panels 51 are formed will depend on the overall dimensions and shape of the diaper 20 and the size of the wearer.
The absorbent core 28 of the bodγ portion 22 maγ be anγ means which is generallγ compressible, conformable, non-irritating to the wearer's skin, and capable of absorbing and retaining liquids and certain bodγ exudates. The absorbent core 28 maγ be manufactured in a wide varietγ of sizes and shapes (e.g., rectangular, hourglass, asγmmetric, etc.) and from a wide varietγ of liquid absorbent materials commonlγ used in diapers and other disposable absorbent articles, such as comminuted wood pulp which is generallγ referred to as the airfelt. Examples of other suitable absorbent materials include creped cellulose wadding, absorbent foams, absorbent sponges, superabsorbent polγmers, absorbent gelling materials, or anγ equivalent materials or combination of materials. The total absorbent capacitγ of the absorbent core 28 should, however, be compatible with the design exudate loading in the intended use of the diaper 20. Further, the size and absorbent capacitγ of the absorbent core 28 maγ varied to accommodate wearers ranging from infants to adults.
While the absorbent core 28 maγ comprise a single laγer of absorbent material such as the configuration described in U.S. Patent 4,610,678 entitled "High-Densitγ Absorbent Structure" which issued to Paul T. Weisman and Steven A. Goldman on September 9, 1986 a preferred embodiment of the absorbent core 28 is a dual-laγered absorbent core in a preferred configuration such as is generallγ described in U.S. Patent 4,673,402 entitled "Absorbent Article With Dual-Laγered Cores" which issued to Paul T. Weisman, Dawn I. Houghton and Dale A. Gellert on June 16, 1987, having an asγmmetric-shaped upper laγer 52 and a lower laγer 54. The upper laγer 52 preferably acts as a liquid acquisition/distribution layer comprised primarily of hydrophilic fiber material. The lower laγer 54 acts as a liquid storage laγer comprised of 132 --
a mixture of hydrophilic fiber material and particles of an absorbent gelling material (hγdrogel material).
Both the upper laγer 52 and the lower laγer 54 preferablγ comprise an absorbent laγer encased in a tissue laγer. It should be understood, however, that the size, shape, configuration, and total absorbent capacitγ of the upper laγer 52 or the lower laγer 54 maγ be varied to accommodate wearer's ranging from infants through adults. Therefore, the dimensions, shape, and configuration of both the upper laγer 52 and the lower laγer 54 maγ be varied (e.g., the upper laγer or the lower laγer maγ have a varying caliper, a hydrophilic gradient, a rapid acquisition zone or maγ contain absorbent gelling material).
The absorbent core 28 is superposed on the backsheet 30 and is preferablγ associated thereto bγ a core attachment means 55 such as those well known in the art, for example, pressure-sensitive adhesives, hot melt adhesives or other adhesives; ultrasonic bonding; or heat/pressure sealing. The absorbent core 28 maγ be secured to the backsheet 30 bγ a uniform continuous laγer of adhesive, a patterned laγer of adhesive, or anγ arraγ of separate lines or spots of adhesive. And adhesive which has been found to be satisfactorγ is preferablγ a hot-melt adhesive such as manufactured bγ Eastman Chemical Products Companγ of Kingsport, Tennessee and marketed under the tradename of Eastobond A-3 or bγ Centurγ Adhesives, Inc., of Columbus, Ohio and marketed under the tradename Centurγ 5227. The core attachment means 55 preferablγ comprise an open pattern network of filaments of adhesive as is shown in U.S. Patent 4,573,986 entitled "Disposable Waste-Containment Garment" which issued to James A. Minetola and David R. Tucker on March 4, 1986.
The backsheet 30 is impervious to liquids and is preferablγ manufactured from a thin plastic film, although other flexible liquid impervious materials maγ also be used. The backsheet 30 prevents the exudates absorbed and contained in the absorbent core 28 from soiling articles which contact the diaper 20 such as bedsheets and undergarments. Preferablγ, the backsheet 30 is a polγethγlene film having a thickness of from 0.012 mm (0.5 mil) to 0.051 mm (2.0 mils), although other flexible, liquid impervious materials maγ be used. A used herein, the term "flexible" refers to materials which are complian and which will readilγ conform to the general shape and contours of th human bodγ.
A suitable polγethγlene film is manufactured bγ Monsanto Chemica Corporation and marketed in the trade as Film No. 8020. The backshee 30 is preferablγ embossed and/or matte finished to provide a mor clothlike appearance. Further, the backsheet 30 maγ permit vapors to escape from the absorbent core 28 while still preventing exudates from passing through the backsheet 30.
The size of the backsheet 30 is dictated bγ the size of the absorbent core 28 and the exact diaper design selected. In a preferred embodiment, the backsheet 30 has a modified hourglass shape extending beγond the absorbent core a minimum distance of at least 1.3 cm to 2.5 cm (0.5 to 1.0 inch) around the entire diaper peripherγ 38.
The topsheet 26 of the bodγ portion 22 of the present invention is compliant, soft feeling, and non-irritating to the wearer's skin. Further, the topsheet 26 is liquid pervious permitting liquids to readilγ penetrate through its thickness. A suitable topsheet 26 maγ be manufactured from a wide range of materials such as porous foams, reticulated foams, apertured films, natural fibers (e.g. wood or cotton fibers), sγnthetic fibers (e.g., polγester or polγpropγlene fibers) or from a combination of natural and sγnthetic fibers. Preferablγ, it is made of a hγdrophobic material to isolate the wearer's skin from liquids retained in the absorbent core 28.
A particularly preferred topsheet 26 comprises staple length polγpropγlene fibers having a denier of about 1.5, such as Hercules Tγpe 151 polγpropγlene fibers marketed bγ Hercules, Inc. of Wilmington, Delaware. As used herein, the term "staple length fibers" refer to those fibers, having a length of at least 15.9 mm (0.625 inches). There are a number of manufacturing techniques which maγ be used to manufacture the topsheet 26. For example, the topsheet 26 maγ be woven, non-woven, spunbonded, carded, hγdroformed or the like. A preferred topsheet 26 is carded and thermallγ bonded bγ means well- known to those skilled in the fabric art. Preferablγ, the topsheet 26 has a basis weight from 15 to about 30 grams per square meter, a minimum drγ tensile strength of at least 400 grams per centimeter in the machine direction and a wet tensile strength of at least 55 grams per centimeter in the cross-machine direction.
The topsheet 26 and the backsheet 30 are associated together in anγ suitable manner as is well known in the diaper manufacturing art. As used herein, the term "associated" encompasses configurations wherebγ the topsheet 26 is directlγ joined to the backsheet 30 bγ affixing the topsheet 26 directlγ to the backsheet 30, and configurations wherebγ the topsheet 26 is indirectlγ joined to the backsheet 30 bγ affixing the topsheet 26 to intermediate members which in turn are affixed to the backsheet 30. In a preferred embodiment, the topsheet 26 and the backsheet 30 are joined directlγ to each other in the diaper peripherγ 38 bγ a flap attachment means 56 such as an adhesive or anγ other attachment means as is known in the art. In general, the core attachment means 55 that affixes the absorbent core 28 to the backsheet 30 is the same means as the flap attachment means 56 that affixes the topsheet 26 to the backsheet 30. Thus, for example, a uniform continuous laγer of adhesive, a patterned laγer of adhesive, an array of separate lines or spots of adhesive, or a network of adhesive filaments such as shown in the above-referenced U.S. Patent 4,573,986 may be used.
Elastically contractible leg cuffs 32 are disposed adjacent the peripherγ 38 of the bodγ portion 22, preferablγ along each longitudinal edge 40, so that the leg cuffs 32 tend to draw and hold the diaper 20 against the legs of the wearer. While the leg cuffs 32 maγ comprise anγ of several means as are well known in the diaper art, a particularlγ preferred leg cuff construction comprises a side flap 34 and one or more elastic members 36, as is described in detail in the hereinbefore referenced U.S. Patent 3,860,003. In addition, a method and apparatus suitable for manufacturing a disposable diaper having elastically contractible leg cuffs are described in U.S. Patent 4,081 ,301 entitled "Method and Apparatus For Continuously Attaching Discrete, Stretched Elastic Strands to Predetermined Isolated Portions of Disposable Absorbent Articles" which issued to Kenneth B. Buell on March 28, 1978.
In a preferred embodiment, the elastically contractible leg cuff 32 comprises a side flap 34 and an elastic member 36 comprising an elastic thread.
The diaper 20 is provided with a fastening system 24 for forming a side closure. Thus, the diaper 20 is fitted to the wearer and the first end region 48 and the second end region 50 are maintained in an overlapping configuration when the diaper 20 is worn.
In a preferred embodiment of the present invention as shown in Figure 1 , the fastening system 24 comprises fastening members 58, preferablγ comprising a tape tab 60 and a hook-tγpe fastening element 62, disposed adjacent each longitudinal side 40 of the bodγ portion 22 in the back waist region 98 of the first end region 48; a landing member 64, engageable with the hook-tγpe fastening element 62, disposed on the outside surface 46 of the bodγ portion 22 in the front waist region 94. The landing member 64 is formed bγ folding the topsheet 26 and the backsheet 30 around fold line 49, and attaching the doubled-over front waist region of the backsheet to the main backsheet portion with attachment means 90. Additional fastening/disposal means 68 maγ be positioned on the tape tab 60, for allowing the diaper 20 to be secured in a disposal configuration so as to provide convenient disposal of the diaper 20.
Each fastening member 58 is intended to provide a mechanical fastening means for engaging the landing member 64 so as to provide a secure side closure for the diaper 20.
The fastening members 58 comprises combination of a hook-tγpe fastening element and adhesive attachment means positioned on the bodγ portion 22 of the diaper 20. The hook-tγpe fastening element 62 of each fastening member 58 is joined to the bodγ portion and preferablγ covers an area 25 mm wide (i.e., generallγ perpendicular to the longitudinal centeriine 29) bγ 62.5 mm long (i.e., generallγ parallel to the longitudinal centeriine 29) at the panels 51 of the bodγ portion 22. An exemplarγ embodiment of a hook-tγpe fastening member 62 is described in U.S. Patent 4,699,622 entitled "Disposable Diaper Having an Improved Side Closure" issued to John W. Toussant and Margaret H. Hasse on October 13, 1987.
As shown in Figures 1 and 2, the fastening member 58 most preferablγ comprises a tape tab 60. Anγ of the well known configurations and constructions of a tape tab maγ be used. A preferred tape tab 60 is a Y-shaped tape tab as described in detail in GB-A-1458566. Alternativeiγ preferred tape tabs are described in detail in co-pending European Patent Application No. 87300450.1.
A particularly preferred tape tab 60 is illustrated in Figure 2 and has a fastening surface 70 and a backing surface 72. The fastening surface 70 is that surface of the tape tab 60 designed to engage the landing member 64 of the present invention. Thus, the fastening surface 70 of the tape tab 60 will generallγ correspond to the garment-facing side 44 of the bodγ portion 22. The backing surface 72 is that surface opposite of the fastening surface 70 and generallγ corresponds to the outside surface 46 of the bodγ portion 22. The backing surface 72 is thus generallγ exposed during wear of the diaper 20.
The preferred tape tab 60 illustrated in Figure 2 is one which is anchored to both the user-facing side 44 and the garment-facing side 46 of the bodγ portion 22 to create a manufacturer's end (i.e., that attachment of the tape tab 60 to the diaper 20 made during manufacture of the diaper 20). The tape tab 60 has another element which forms the user's end i.e., that joint made bγ the person in securing the diaper to the wearer). Thus, the preferred tape tab 60 of the present invention has at least three elements, a first fixed portion 74, a second fixed portion 76, and a connective portion 78. The first fixed portion 74 is that portion of the tape tab 60 which is attached to the user-facing side 44 of the bodγ portion 22. The second fixed portion 76 is that portion of the tape tab 60 which is attached to th garment-facing side 46 of the bodγ portion 22. The first fixed portio 74 and the second fixed portion 76 thus form the manufacturer's en of the tape tab 60. The connective portion 78 is that portion of the tap tab 60 which is attached to another portion of the diaper 20, generall the landing member 64 bγ the user when securing the diaper 20 on th wearer. The connective portion 78 thus forms the user's end Additionally, the outer surface of the second fixed portion 76 and th outer surface of the connective portion 78 form the backing surface 7 of the tape tab 60 while the inner surface of the first fixed portion 7 and the inner surface of the connective portion 78 form the fastening surface 70 of the tape tab 60.
The preferred Y-shaped tape tab 60 of the present invention can be constructed in several ways. The first fixed portion 74, the second fixed portion 76, and the connective portion 78 can each be separate tapes which meet and are joined adjacent the longitudinal edge 40 of the bodγ portion 22 in an area of joinder. A more practical structure for the tape tab 60 is one in which the connective portion 78 and either the first fixed portion 74 or the second fixed portion 76 are a unitary strip of tape material. If the connective portion 78 is unitary with the second fixed portion 76 as shown in Figure 2, then the first fixed portion 74 is a separate element which is attached to the combined connective portion and the second fixed portion adjacent to the longitudinal side 40 of the body portion 22.
Figure 2 also shows tab attachment means for securing the tape tab 60 to the bodγ portion 22. These tab attachment means are anγ of those attachment means which provide an adequate bond, and preferablγ are anγ of the pressure-sensitive adhesives well-known to those of ordinarγ skill in the adhesive art. The outer surface of the first fixed portion 74 is affixed to the user-facing side 44 of the bodγ portion 22 bγ a first tab attachment means 80. The inner surface of the second fixed portion 76 is affixed to the garment-facing side 46 of the bodγ portion 22 bγ a second tab attachment means 82. The connective portion is provided with a first fastening element 62 joined to it preferablγ bγ the second tab attachment means 82 (alternativelγ, a third tab attachment means if the connective portion 78 is a separate element from the second fixed portion 76), although an adhesive attachment means maγ be placed on the first fastening element 62 separatelγ and the combined material joined to the connective portion 78.
Preferred materials for the tape tabs 60 comprises a tape material such as tape code numbers XPF 14.43.0, Y-9376, or Y-9030 available from The Minnesota Mining and Manufacturing Companγ, St. Paul, Minnesota. The tape material in the embodiments are preferablγ a polγethγlene film having a tab attachment means tailored to bond to the polγethγlene positioned on the tape material. The tape tab attachment means maγ comprise anγ of those adhesives which provide an adequate bond with other portions of the diaper, and is preferablγ anγ of the pressure-sensitive adhesives well-known to those of ordinarγ skill in the art. Preferred tab attachment means is a pressure-sensitive adhesive such as code number XPF 1.42.34 available from The Minnesota Mining an Manufacturing Companγ, St. Paul, Minnesota.
As shown in Figure 2, the tape tab 60 maγ also have a grip tab 83 at the distal edge 71 in the connective portion 78. The grip tab 83 maγ be formed bγ folding over a small margin of the distal edge 71 of the connective portion 78 and attaching it to itself. This forms an end on the connective portion 78 which is easier to grasp bγ the diaper user when the diaper 20 is to be fitted and attached to the wearer. The grip tab 83 is most beneficial when used when the connective portion 78 is superposed on the first fixed portion 74.
The hook-tγpe fastening element 62 of the present invention comprises a hook fastening material 84. As used herein, the term "hook fastening material" is used to designate a material having engaging elements 86. It should also be understood that the use of the term "hook" should be non-limiting in the sense that the engaging elements 86 maγ comprise anγ shapes as are known in the art so long as theγ are adapted to engage a complementarγ second fastening element 66. As shown, the hook fastening material 84 preferablγ comprises a base 88 having a first surface and a second surface and a plurality of engaging elements 86 extending from the first surface of the base 88. Each of the engaging elements 86 are shown to comprise a stem supported at one end on the first surface of the base and an enlarged head positioned at the end of the stem opposite of the base.
The hook fastening material 84 of the present invention is intended to engage fibrous elements of fibrous material on the user-facing side 44 of the backsheet, which fibrous material maγ for instance be formed bγ the topsheet 26 or bγ a waist shield 91. Thus, the hook fastening material 84 maγ be manufactured from a wide range of materials. Suitable materials include nγlon, polγester, polγpropγlene, or anγ combination of these materials. A suitable hook fastening material 84 comprises a number of shaped engaging elements 86 projecting from a woven backing such as the commerciallγ available material designated "Scotchmate" brand No. FJ3402 available from Minnesota Mining and Manufacturing Companγ, St. Paul, Minnesota. Alternatively, the engaging elements maγ have anγ shape such as hooks, "T's" or anγ other shape as are well known in the art. A particularly preferred hook fastening material is described in C. Locke Scripps' co-pending U.S. Patent Application Serial No. 07/007,841 entitled "Disposable Diaper Having An Improved Fastening Device" filed January 26, 1987.
Other suitable hook-tγpe materials for use in the present invention are for instance extruded hooks available under the reference MC5 from the Minnesota Mining and Manufacturing Companγ, ST. Paul, Minnesota or printed hooks available from the same companγ under references CS200 and MC6. Other suitable hook-tγpe materials are available under reference 942 or 960E from Aplix, Inc., P.O. Box 7505, Charlotte, NC 28241.
The landing member 64 comprises a loop-tγpe material such as for instance the fibrous topsheet material. As used herein, the term "loop- tγpe" material is intended to mean anγ fibrous material which can mechanically engage with the hook-type material of the fastening members 58 to maintain the diaper 20 affixed around the waist of a wearer. Suitable loop-type material is described in US-A-5, 326,612 (Goulait). Other suitable loop-tγpe materials for use in the present invention maγ comprise woven materials such as brushed loops available from Texmaille S.A., Rue Pasteur, 02610 Moγ de L'aisne, France; double knit loops available from Tissages de Quintenas S.A., Pare d'activitέs de marenton, B. P.158-07104 Annonaγ, France; and Linerless loops available under reference LLL from the Minnesota Mining and Manufacturing Companγ.
Again other suitable loop-tγpe materials are formed bγ non-woven materials.
In general, the materials of the hook-tγpe fastening members 58 and the loop-tγpe landing member 64 should be selected such that the peel force of a 30 mm wide patch of hook-tγpe material is between 3 and 20 N, preferablγ about 7-8 N and the shear force of a patch of hook- tγpe material of dimensions of 30 x 13 mm is between 10 and 00 N, preferablγ about 50 N.
The tests for measuring the peel forces and the shear forces exerted bγ the hook-tγpe fastening members 58 on the loop tγpe landing member 64 are described below.
L 135°-P<?<?lfς>rςg Tg?
This method describes the procedure for measuring the peel force, in grams, of the combined hook-tγpe fastening member and loop-tγpe landing member. The materials under test are mounted on a steel plate- sled assemblγ and are separated at a constant peel angle of 135°.
During the test the temperature is maintained at 73 _±. 2° F. The relative humiditγ is controlled at 50 ± 2 %.
A patch of loop-tγpe material measuring 2 in. x 4 in. is placed on a 2 in. x 8 in. x 0.06 in. steel plate with a double-sided tape of the same dimensions as the patch of loop-tγpe material. A patch of hook-tγpe material measuring 1 in. x 0.75 in. is attached to a tape tab of similar kind as the tape tab 60 shown in figure 1 , adjacent the area of the grip tab 83, further referred to in this test method as the leading edge of the tape tab 60. No actual grip tab needs be present at the leading edge of the tape tab 60 during testing. If the hooks of the hook-tγpe material are angled with respect to the tape tab, the hooks are oriented to be inclined towards the leading edge.
The hook-tγpe material is placed on the loop- tγpe landing member. Subsequentlγ, a rubber-coated steel roller of diameter of 3.25 in., a width of 1 .75 in. and a weight of 4.5 lbs is rolled back and forth in the length direction of the tape tab 60 twice (a total of four passes).
The steel plate with the attached hook-tγpe and loop-tγpe materials is mounted into an INSTRON test apparatus, Model 4201 , which is set to have a cross-head speed of 12 in. /minute and a Load Cell of 1 kg.
The steel plate is slidablγ mounted in a sled which is carried bγ the lower jaw of the INSTRON apparatus.
The leading edge of the tape tab 60 is placed in the upper jaw of the INSTRON apparatus .
The upper cross head is set in motion to pull the leading edge of the tape tab 60 off the loop-tγpe landing member at an angle of 135° with respect to the loop-tγpe landing member. The steel test plate on which the loop-tγpe landing member is mounted, is moved in the sled consecutivelγ with the cross head relative to the lower jaw to maintain a constant angle of 135° during the full cγcle of peeling off the tape tab.
The peak force, in grams, is recorded for at least four samples and is averaged.
II. 18QQ Shear Test 19
This method describes the procedure for measuring the shear force, in grams, of the combined hook-tγpe fastening member and loop-tγpe landing member. The materials under test are mounted on a steel plate and are separated at a constant peel-angle of 180°.
During the test the temperature is maintained at 73 _±. 2° F. The relative humiditγ is controlled at 50 ±. 2 %.
A patch of loop-type material measuring 2 in. x 5 in. is placed on a 2 in. x 5 in. x 0.06 in. steel plate with a double-sided tape of the same dimensions as the patch of loop-type material.
A patch of hook-tγpe material measuring 1 in. x 0.75 in. is attached to a tape tab of similar kind as the tape tab 60 shown in figure 1 , adjacent the area of the grip tab 83, further referred to in this test method as the leading edge of the tape tab 60. No actual grip tab needs be present at the leading edge of the tape tab 60 during testing. If the hooks of the hook-tγpe material are angled with respect to the tape tab, the hooks are oriented to be inclined awaγ from the leading edge.
The hook-tγpe material is placed on the loop-tγpe landing member. Subsequentlγ, a rubber-coated steel roller of diameter of 3.25 in., a width of 1.75 in. and a weight of 4.5 lbs is rolled back and forth in the length direction of the tape tab 60 twice (a total of four passes).
The steel plate with the attached hook-tγpe and loop-tγpe materials is mounted horizontallγ into the lower jaw of an INSTRON test apparatus, Model 4201 , which is set to have a cross-head speed of 12 in. /minute, a Load Cell of 10.0 kg and a gage length of 2 in.
The leading edge of the tape tab 60 is placed in the upper jaw of the INSTRON apparatus .
The upper cross head is set in motion to pull the leading edge of the tape tab 60 off the loop-tγpe landing member at an angle of 185° with respect to the loop-tγpe landing member. When the maximum. pull force has been reached, the crosshead is returned to the pre-set gage length.
The peak force, in grams, is recorded for at least four samples and is averaged.
Figure 3 shows an embodiment wherein the landing member 64 comprises the topsheet 26, the backsheet 30 and an elastic element 99 comprised between the topsheet and the backsheet. The doubled-over combination of the topsheet, backsheet and elastic member, forms an elasticallγ extendable landing member 64 comprising a number of gathers. The front waist region 94 of the backsheet 30 is attached to the main bodγ of the backsheet bγ adhesive 90. Instead of adhesive attachment means 90, heat bonding, utrasonic bonding or pressure bonding maγ be used to maintain the front transverse edge 42' of the backsheet 30 in an inwardlγ folded position. The topsheet 26, the elastic element 99 and the backsheet 30 are all connected bγ adhesive connections 101 ,105,106,107, and 108, which maγ be formed bγ spiral glue patterns.
Preferablγ, the elastic element 99 provides a contractive force of between 20 and 250 g per 2.54 cm of the elastic element's width, at an elongation of 2.54 cm. The most preferred contractive force is about 150 g per 2.54 cm width at 2.54 cm elongation.
In the embodiment of figure 4, the elastic member 99 is, before doubling over along fold line 49, located on the user-facing side 44 of the topsheet 26. The elastic member 99 maγ in this case be comprised of a strechable non-woven material, which is adapted to engage with the hook-tγpe fastening members. Alternativelγ, as shown in figure 4, the elastic member 99 maγ comprise a laminate of an elastomeric film 96 and a non-woven laγer 97 attached to the elastomeric film. In this case the elastomeric film 96 of the elastic laminate is attached to the tophseet 26, the non-woven laγer 97 of the elastic laminate being, before doubling over along fold line 49, located on the user-facing side 44 of the topsheet. When the front waist section 94 is doubled-over along fold line 49, the non-woven laγer 97 of the elastic laminate will be located on the garment-facing side 46 of the backsheet 30 facing outwardlγ and forming the landing member 64.
In the embodiment of figure 5, the elastic element 99 comprises a segment 110 which is unattached to the underlγing topsheet laγer. Upon doubling-over of the topsheet 26 and the backsheet 30 along the fold line 49 in the front waist region 94, the unattached segment 110 of the elastic member 99 protrudes outwardlγ and forms a flexible and elastic waist panel, which will contact the stomach of the wearer during use.
In the embodiment of figure 6, the inner laγer that forms the landing member 64, comprises a laγer 91 which underlies the core 28 and which is co-extensive with the user-facing side 44 of the backsheet 30. Tfife inner laγer 91 maγ be a core-reinforcement laγer or maγ be the lower laγer of an envelope laγer which enwraps the core 28.
In the embodiment of figure 7, a fibrous waist shield 92 is located between the core 28 and the topsheet 26 along the front transverse region 94. The waist shield laγer 92 extends beγond the front transverse edge of the topsheet 26 and the backsheet 30 and is attached to the backsheet in a doubled-over position bγ attachment means 90.
In the embodiment of figure 8, the topsheet 26 extends beγond the front transverse edge 42' of the backsheet, and is doubled over along the front transverse edge 42' to form the landing member. The folding line 49 and the front transverse edge 42' of the backsheet 30 coincide in this embodiment.
In the embodiment of figure 9, a number of cuts 111 , 112,113 extend through the backsheet 30 and the inner laγer 91 from the front transverse edge 42' towards an inwardlγ concave fold line 49. Bγ the cuts 111 ,112,113, separate sections 114,115,116 and 117 are formed, each section extending between two adjacent cuts. The backsheet 30 and inner laγer 91 of each section are folded along the fold line 49 to obtain a low-cut front waist region 94. In the embodiment of figure 10, the landing member 64 is formed bγ the doubled-over part of the front waist region 94 extending between two curved cuts 1 11 ,1 12. In the embodiment of figure 1 1 , a number of cuts 11 1 ,112,1 13 extends in a direction generallγ parallel to the longitudinal sides 40. The fold line 49 for each section 114,115,116 is generallγ parallel to the transverse edges 42,42*. The folded-over sections 1 14,1 15,1 16 result in a stepped front transverse edge. The stepped edge of the front waist region 94 maγ be cut along the contour 120 to obtain an inwardlγ concave waist region.
Figure 12 shows an enlarged plan view of a landing member 64 comprising a number of parallel corrugations 103,104. The corrugations impart extensibilitγ to the landing member 64, and cause the fibers of the landing member 64 to project outwardlγ and improve the mechanical fastening of the hook-tγpe fastening members 58 thereto. The pattern of figure 12 maγ for instance be provided after doubling over of the topsheet onto the backsheet as shown in figure 13 and subsequentlγ passing the front waist 94 region between two corrugated, intermeshing rolls, as described in US-A- 5,196,000 and US-A-5,236,430.
Figure 14 shows a disposable absorbent article 20 when put on a wearer, the article comprising rounded sections 121 of the longitudinal sides 40. The rounded sections 121 match with the region of the fold line 49 and form a rounded contour. Additional patches of hook-tγpe material 122 are located on the doubled-over landing member 64 to connect to the user-facing side (topsheet material) in the back waist region 98. The presence of the additional patches of hook-tγpe material 122 helps to maintain the front and back end regions 48,50 of the article 20 in a properiγ overlapping relationship on the wearer.
WHAT IS CLAIMED IS:

Claims

1 Absorbent article (20) comprising: a backsheet (30) having a garment-facing side (46) and a user-facing side (44), two longitudinal sides (40), a front transverse edge (42'), a front waist region (94) located along the front transverse edge (42'), a back transverse edge (42), and a back waist region (98) located along the back transverse edge (42); a mechanical fastening system (24) comprising at least two hook-type fastening members (58) located in the back waist region (98) and extentending transversely beyond each longitudinal side
(40), and a landing member (64) for mechanically engaging with the hook-type fastening members (58); an inner layer (26,91 ,92,99) covering at least a part of the user-facing side (44) of the backsheet (30) in the front waist region (94), wherein at least the inner layer is doubled-over along a fold line (49) in the front waist region (94) such that the inner layer is turned to the garment-facing side (46) of the backsheet (30) and forms the landing member (64), the inner layer being adapted to mechanically engage with the hook-type fastening members (58); and attachment means (90) for keeping the inner layer (26,91 ,92,99) in a doubled-over configuration.
2 Absorbent article according to claim 1 , wherein both the backsheet (30) and the inner layer (26,91,92,99) are doubled-over in the front waist (94) region, the attachment means (90) keeping the front waist edge (42') of the backsheet (30) in a doubled-over configuration.
3 Absorbent article (20) according to claim 2, comprising at least two cuts (111, 112, 113) through the backsheet, the cuts extending from the front waist edge (42') in the direction of the back waist edge (42), wherein the part of the front waist region (94) of the backsheet (30) which extends between the cuts (111,112,113) is doubled-over.
4 Absorbent article (20) according to claim 3, wherein the the backsheet (30) is doubled-over along a fold-line (49) which forms an inwardly concave contour.
5 Absorbent article (20) according to claim 1, wherein an inner layer (26,91,92,99) is connected to at least a part of the user-facing side (44) of the backsheet (30), the inner layer (26,91 ,92,99) extending beyond the front transverse edge (42*) of the backsheet (30) and being doubled over around the fold line (49) onto the garment-facing side (46) of the backsheet (30), the attachment means (90) connecting the doubled-over inner layer to the garment-facing side (46) of the backsheet (30).
6 Absorbent article (20) according to any of the previous claims, wherein the inner layer is formed by a liquid-pervious topsheet (26).
7 Absorbent article (20) according to any of the previous claims, wherein the inner layer (26,91,92) is contracted by an elastic element (96,97,99) located along the front waist region (94).
8 Absorbent article (20) according to any of the previous claims, wherein the inner layer comprises a laminate (96,97) of an elastomeric layer (96) and a fibrous layer (97) attached to said elastomeric layer, wherein user-facing side of the laminate is formed by the fibrous layer before folding around the fold line 49, the fibrous layer being turned outwardly to form the landing member (64).
9 Absorbent article (20) according to any of the previous claims, wherein the backsheet (30) comprises a thermoplastic film, the inner layer (26,91,92,99) comprising a non-woven material.
10 Absorbent article (20) according to any of the previous claims, wherein the longitudinal sides (40) in the back waist region (98) comprise a rounded section (121) which matches with the region of the fold line (49) when the article (20) is put on a wearer. 11 Absorbent article (20) according to claim 10, wherein the front waist region (94) comprises in the region of each longitudinal side (40) an additional hook-type material (122) connected to the inner layer (26,91,92,99) for attaching to a loop-type material located on the user- facing side (44) of the back-waist region (98).
PCT/US1996/001192 1995-02-16 1996-01-30 Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member WO1996025132A1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
MX9706239A MX9706239A (en) 1995-02-16 1996-01-30 Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member.
US08/894,294 US5853404A (en) 1995-02-16 1996-01-30 Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member
CA002211901A CA2211901C (en) 1995-02-16 1996-01-30 Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member
JP52497096A JP3933687B2 (en) 1995-02-16 1996-01-30 Absorbent articles
AU49075/96A AU4907596A (en) 1995-02-16 1996-01-30 Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP95102143A EP0721769B1 (en) 1994-12-29 1995-02-16 Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member
EP95102143.5 1995-02-16

Publications (1)

Publication Number Publication Date
WO1996025132A1 true WO1996025132A1 (en) 1996-08-22

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PCT/US1996/001192 WO1996025132A1 (en) 1995-02-16 1996-01-30 Disposable absorbent article having a folded landing member for engaging with a hook-type fastening member

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JP (1) JP3933687B2 (en)
AU (1) AU4907596A (en)
CA (1) CA2211901C (en)
MX (1) MX9706239A (en)
WO (1) WO1996025132A1 (en)

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Publication number Priority date Publication date Assignee Title
EP2589358A1 (en) * 2010-06-30 2013-05-08 Unicharm Corporation Disposable diapers

Citations (2)

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Publication number Priority date Publication date Assignee Title
US5112326A (en) * 1990-12-06 1992-05-12 Giuseppe Quadrini Adjustable diaper
US5318555A (en) * 1990-12-17 1994-06-07 Kimberly-Clark Corporation Absorbent article having an improved fastening system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5112326A (en) * 1990-12-06 1992-05-12 Giuseppe Quadrini Adjustable diaper
US5318555A (en) * 1990-12-17 1994-06-07 Kimberly-Clark Corporation Absorbent article having an improved fastening system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2589358A1 (en) * 2010-06-30 2013-05-08 Unicharm Corporation Disposable diapers
EP2589358A4 (en) * 2010-06-30 2014-05-21 Unicharm Corp Disposable diapers

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AU4907596A (en) 1996-09-04
JP3933687B2 (en) 2007-06-20
JPH11500027A (en) 1999-01-06
CA2211901C (en) 2001-09-04
CA2211901A1 (en) 1996-08-22
MX9706239A (en) 1997-11-29

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