Note: Descriptions are shown in the official language in which they were submitted.
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ABSORBENT ARTICLE WITH ELASTICALLY EXTENSIBLE LANDING MEMBER
Field of the Invention
The invention relates to disposable absorbent articles comprising a
mechanical fastening system.
Such disposable absorbent articles are know from EP-A- 0 321 234.
Known mechanical fastening systems for use in disposable absorbent
articles comprise tape tabs comprising a hook-type fastening element in the
back waist region wherein the hooks mechanically engage with a landing
member. The landing member is a loop-type material located in the front
waist region on the garment-facing side of the article which entangles with
the hooks of the tape tabs to form a closure having resistance against peel
forces and shear forces.
The loop-type materials used for the landing members of the known
mechanical fastening systems are relatively expensive materials.
Furthermore, the known loop-type materials are attached to the garment-
facing side of the backsheet and form an extra layer that increases the bulk
of the absorbent articles upon compression-packaging of these articles in a
compressed array.
By attaching relatively small sized patches of loop-type material to the
backsheet, the complexity of the production process for making an
absorbent article is increased. The addition of larger patches, or strips of
loop-type material to the garment-facing side of the backsheet, may cause
the elastic expansion of the materials in the front waist region of the
absorbent article to be impaired.
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Finally, when an etasticated front waist region is provided in an absoroent
article, the material of the backsheet in this region will comprise a number
of
gathers or surface irregularities, caused by the contraction of the elastic
element in the front waist region. Patches of loop-type material cannot
properly be attached to such irregularly shaped surfaces.
It is therefore an object of an aspect of the present invention to provide an
absorbent article having a mechanical fastening system which allows good
conformability of the front waist region to the movements of the user and
which allows dynamic and self-adjusting fit of the front waist region.
It is another object of an aspect of the present invention to provide an
absorbent article having a mechanical fastening system which can easily
be applied in the region of an elasticated front waist region.
It is again another object of an aspect of the invention to provide a
mechanical fastening system which is of relatively simple construction and
which is cost-effective.
It is a further object of an aspect of the invention to provide an absorbent
article comprising a mechanical fastening system which is of low bulk
when packed in a compressed array.
Summary of the invention
An absorbent article according to the invention comprises a garment-facing
backsheet having two longitudinal sides, a front transverse edge, and a
back transverse edge. The article has a mechanical fastening system for
attaching the articie to a wearer, comprising at least two hook-type
fastening members located in the region of the back transverse edge and
extending transversely beyond each longitudinal side. A loop-type landing
member is located in the region of the front transverse edge for
mechanically engaging with the hook-type fastening members, wherein the
landing member is elastically extensible by at least 5 % in the direction of
the front transverse edge.
The landing member may be made of an elastic loop-type material, such as
for instance an elastic non-woven material. The elastic loop-type material in
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such an embodiment forms the front waist elastic eiement of the front waist
region while simultaneously allowing the hook-type material to fasten the
absorbent article on the wearer. Altemativeiy, the landing member
comprises a non-elastic loop-type material, which is laminated to an elastic
film.
The above landing members may be attached to the garment-facing side of
the front waist region of the backsheet in a pre-stretched manner, such that
the contraction of the landing member contracts the front waist region in a
number of gathers. Altematively, the landing member may be attached to
the backsheet in a relaxed state, and may be subsequently mechanically
deformed or pre-strained to impart extensibility to the landing member.
Mechanical deformation may for instance be imparted by passing the
landing member between a pair of intermeshing, grooved rolls, such as
described in US-A-5,196,000 and US-A-5,236,430.
The landing member may also comprise a patch or strip of loop-type
material that is superimposed on a front waist elastic element applied to the
topsheet or the backsheet of the absorbent article in the front waist region,
such that the loop-type material is contracted by the waist elastic element in
gathers. The contraction of the front waist elastic element will cause the
loops, or fibers, on the surface of the landing member to project outwardly,
and thereby improves the fastening characteristics thereof.
In one embodiment of an absorbent article according to the invention, an
inner layer is located on the garment-facing side of the backsheet. The
landing member comprises at least one cut-out section extending through
the backsheet and exposing the underlying inner layer. The part of the
underlying layer located below the at least one cut-out section, is adapted
to mechanically engage with the hook-type fastening members and forms a
part of the landing member.
By cutting an aperture through the backsheet material, the inner layer below
the badcsheet is exposed through the aperture. 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. Altematively, the inner layer may be a layer which is
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located below the absorbent core or may be a high wet-strength tissue
which envelopes the core. By selecting the hook-type fastening members
to match the non-woven material that is regularly employed as an inner
layer, the hooks can mechanically engage with these layers to fasten the
absorbent article around a wearer.
In another embodiment of an absorbent article according to the invention,
the landing member defines a landing zone for receiving the hook-type
fastening members, wherein the backsheet does not extend into the landing
zone. The inner layer extends beyond the front transverse edge of the
backsheet into the landing zone to form the landing member.
By employing a backsheet which is shorter than the inner layer, the fibrous
inner layer is exposed in the front waist region. The fibrous inner layer may
be the topsheet which covers the absorbent core, or may be a layer which is
located below the absorbent core or which envelops the core.
In a further embodiment of an absorbent article according to the invention,
the landing member defines a landing zone for receiving the hook-type
fastening members. The backsheet comprises a first section located outside
the landing zone and a second section joined to the first section, the
second section comprising a different material from the first section. The
second section is at least partly located in the front waist region and forms
the landing member.
In this way a soft and compliant waist panel is obtained to which no
separate patches of loop-type material need be attached. Hence a process
simplification is obtained, and no additional bulk is added to the backsheet.
Furthermore, since the landing member is formed by the front waist section
of the backsheet, the landing member extends substantially along the full
width of the front transverse edge, and hence allows for numerous positions =
of attachment of the hook-type fastening members. The backsheet section
in the front waist region may comprise an elastic non-woven material or may
be elasticated and contracted in gathers by a separate elastic element
without the landing member interfering with the elastic properties of the
front
waist region.
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In again another embodiment of an absorbent article according to the
invention, at least the inner layer on the user-facing side of the article is
doubled-over along a fold line in the front waist region such that the inner
layer is tumed to the garment-facing side of the backsheet and forms the
landing member. Attachment means are provided for keeping the inner
layer 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 front
transverse edge. Altematively, the inner layer is co-extensive with the
backsheet, both the backsheet and the inner layer being doubled-over in
the front waist region.
By tuming 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.
In one embodiment of an article according to the invention, at least two cuts
extend through the backsheet extending 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.
By doubling-over the backsheet along these cuts, a low-cut front waist
region can be obtained which fits below the belly of the wearer in the so-
called "low motion zone". Preferably, a number of cuts extend radially from
the front waist edge towards an inwardly concave folding line, such that a
number of backsheet-material sections are formed which are each folded
along the concave folding line. In this manner a shaped front transverse
edge and the landing member are formed simultaneously.
The landing member in the above embodiments is formed by the material of
the inner layer, which 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 front waist region, is required when elastic elements are located in
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the front waist region to provide a snug fit of the article around the waist
of
the wearer.
For fibrous inner layers having relatively little surface irregularities,
relatively small and sharply pointed hooks will be required for the hook-
type material of the fastening members to be able to engage with such a
layer. For non-woven sheets or tissues which comprise a relatively large
number of protruding loops at their surface, the hooks of the hook-type
material may be of larger size and may be relatively flexible to obtain
mechanical attachment to such sheets or tissues. Alternatively, the surface
texture of the inner layers can be selected to match a given type of hook-
fastening material to achieve proper fastening.
The backsheet may be comprised of a non-woven material, a
thermoplastic film or a laminate of a non-woven material and a film. The
backsheet may be formed of an elastic material. There may be additional
layers located between the topsheet and the backsheet.
In accordance with one embodiment of the invention, an absorbent article
comprises:
a backsheet having a user facing side, a garment facing side, two
longitudinal sides, a first transverse edge, a first waist region located
along
the first transverse edge, a second transverse edge, a second waist region
located along the second transverse edge, a first section having a first
section edge and a second section joined to the first section, the second
section extending longitudinally outwardly from the first section edge and
comprising a different material from the first section,
an absorbent core located adjacent the user facing side of the
backsheet, and
a mechanical fastening system comprising:
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at least one hook-type fastening member located in the second
waist region and extending transversely beyond one longitudinal side, and
an extensible landing member located in the first waist region for
mechanically engaging with the hook-type fastening member, the landing
member being formed from a portion of the second section of the
backsheet which is located in the first waist region and which extends
longitudinally outwardly from the first section of the backsheet.
Brief Description of the Drawings
The invention will be described in detail with reference to the
accompanying drawings. In the drawings:
Figure 1 shows a partially cut-away perspective view of a disposable
diaper comprising an elastically extends landing member according to the
invention, Figure 2 shows a cross-sectional view through a hook-type
fastening member of figure 1 along a line of cross section parallel to the
back transverse edge, Figures 3-7 show a cross-sectional view of different
embodiments of the front waist region of the diaper of figure 1 along a line
of cross-section parallel to the front transverse edge and running through
the front waist elastic element, Figure 8 shows a partially cut-away
perspective view of a disposable diaper comprising an elastically
extensible landing member comprising cut-out sections in the backsheet,
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Figures 9-11 show cross-sectional views of different embodiments of the
front waist region of the diaper of figure 8 along a line or cross-section
parallel to the front transverse edge and running through the front waist
elastic element,
Figure 12-14 show schematic perspective views of the garment-facing side
of different embodiments of an absorbent article comprising cut-out sections
in the backsheet,
Figure 15 shows a partially cut-away perspective view of a disposable
diaper wherein the topsheet projects beyond the backsheet in the front
waist region,
Figures 16-19 show cross-sectional views of different embodiments of the
absorbent article of figure 15 along the longitudinal centerline,
Figure 20 shows a schematic perspective view of an absorbent article
wherein the backsheet comprises a curved front transverse edge,
Figure 21 shows a cross-sectional view of the absorbent article of figure 20
along line 20-20,
Figure 22 shows a cross-sectional view of an altemative embodiment of the
absorbent article of figure 20 along line 20-20,
Figure 23 shows an enlarged schematic sectional view of a pre-strained
landing member comprising a number of parallel corrugations,
Figure 24 shows a schematic perspective view of an absorbent article
comprising a landing member as shown in figure 23,
Figure 25 shows a partially cut-away perspective view of a disposable
diaper comprising two different backsheet sections,
Figures 26-28 show cross-sectional views of different embodiments of the
absorbent article of figure 25 along the longitudinal centerline,
Figure 29 shows a partially cut-away perspective view of a disposable
diaper comprising a doubled-over front waist region,
Figures 30-32 show schematic cross-sectional views of the front waist
region of an absorbent article of figure 29,
Figure 33-36 show schematic perspective views of different embodiments of
an absorbent article having a doubled-over front waist region, and
Figure 37 show a disposable absorbent article comprising curved sections
of the longitudinal sides in the back waist region, a doubled over front waist
region and additional hook-type fasteners attached thereto.
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Detailed Descriotion of the Invention
Mechanical fastening systems 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 body exudates and, more specifically, refers to articles which are
placed against or in proximity to the body of the wearer to absorb and
contain the various exudates discharged from the body and which are
intended to be discarded after a single use (i.e., they 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 temn "diaper' refers to a garment generally wom by 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 very readily 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 system illustrated and described herein may be applied to. the
body portion of such diapers. On the other hand, it will be understood that
the invention is not limited to any specific diaper structure or
configuration.
Referring to the drawings, it will be noted that Figure 1 is a partially cut-
away perspective view of the diaper 20 of the present invention prior to its
being placed on the diaper wearer by the diaper user. As can be seen in
Figure 1, a preferred diaper 20 comprises a body portion 22 and a fastening
system 24. A preferred body portion 22 comprises a liquid pervious
topsheet 26, an absorbent core 28, a liquid impervious backsheet 30, and
elastically 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 may be
assembled in a variety of well-known configurations, a preferred disposable
diaper configuration is shown and described generally in the above-
referenced U.S. Patent 3,860,003 which issued to Kenneth B. Buell on
January 14, 1975.
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Figure 1 shows a preferred embodiment of the body portion 22 in which the
topsheet 26 and the backsheet 30 are coextensive and have length and
width dimensions generally larger than those of the absorbent core 28. The
topsheet 26 is superposed on the backsheet 30 thereby forming the
periphery 38 of the body portion 22. The periphery 38 defines the outer
perimeter or, in other words, the outer extend of the body portion 22. The
periphery 38 comprises longitudinal sides 40 and end edges or transverse
edges 42, 42. The body 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 front transverse edge 42' 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 any layer comprised in the diaper 20 is the side of
the layer farthest from the wearer during use. When a backsheet 30 is used,
it typically forms the garment-facing side 46 of the body 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 typically formed by 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 wom. The user-facing
side of any layer comprised in the diaper 20 is the side of the layer closest
to the user when the diaper 20 is wom.
The diaper 20 has first and second end regions 48 and 50, respectively,
extending from the transverse edges 42, 42' of the diaper periphery 38
toward the transverse centerline 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 haif 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 fomned will depend on the overall
dimensions and shape of the diaper 20 and the size of the wearer.
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The absorbent core 28 of the body portion 22 may be any means which is
generally compressible, conformable, non-irritating to the wearer's skin, and
capable of absorbing and retaining liquids and certain body exudates. The
absorbent core 28 may be manufactured in a wide variety of sizes and
shapes (e.g., rectangular, hourglass, asymmetric, etc.) and from a wide
variety of liquid absorbent materials commonly used in diapers and other
disposable absorbent articles, such as comminuted wood pulp which is
generally referred to as the airfelt. Examples of other suitable absorbent
materials include creped cellulose wadding, absorbent foams, absorbent
sponges, superabsorbent polymers, absorbent gelling materials, or any
equivalent materials or combination of materials. The total absorbent
capacity 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 capacity of the absorbent core 28 may varied to
accommodate wearers ranging from infants to adults.
While the absorbent core 28 may comprise a single layer of absorbent
material such as the configuration described in U.S. Patent 4,610,678
entitled "High-Density 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-layered absorbent core in a
preferred configuration such as is generally described in U.S. Patent
4,673,402 entitled "Absorbent Article With Dual-Layered Cores" which
issued to Paul T. Weisman, Dawn I. Houghton and Dale A. Gellert on June
16, 1987, having an asymmetric-shaped upper layer 52 and a lower layer
54. The upper layer 52 preferably acts as a liquid acquisition/distribution
layer comprised primarily of hydrophilic fiber material. The lower layer 54
acts as a liquid storage layer comprised of a mixture of hydrophilic fiber
material and particles of an absorbent gelling material (hydrogel material).
Both the upper layer 52 and the lower layer 54 preferably comprise an
absorbent layer encased in a tissue layer. It should be understood,
however, that the size, shape, configuration, and total absorbent capacity of
the upper layer 52 or the lower layer 54 may be varied to accommodate
wearer's ranging from infants through adults. Therefore, the dimensions,
shape, and configuration of both the upper layer 52 and the lower layer 54
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may be varied (e.g., the upper layer or the lower layer may have a varying
caliper, a hydrophilic gradient, a rapid acquisition zone or may contaln
absorbent gelling material).
The absorbent core 28 is superposed on the backsheet 30 and is preferably
associated thereto by 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 heaUpressure sealing.
The absorbent core 28 may be secured to the backsheet 30 by a uniform
continuous layer of adhesive, a pattemed layer of adhesive, or any array of
separate lines or spots of adhesive. And adhesive which has been found to
be satisfactory is preferably a hot-melt adhesive such as manufactured by
Eastman Chemical Products Company of Kingsport, Tennessee and
marketed under the tradename of Eastobond A-3 or by Century Adhesives
Inc., of Columbus, Ohio and marketed under the tradename Century 5227.
The core attachment means 55 preferably comprise an open pattem
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 preferably manufactured
from a thin plastic film, although other flexible liquid impervious materials
may 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. Preferably, the backsheet
30 is a polyethylene 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 may
be used. As used herein, the term 'llexible" refers to materials which are
compliant and which will readily conform to the general shape and contours
of the human body.
A suitable polyethylene film is manufactured by Monsanto Chemical
Corporation and marketed in the trade as Film No. 8020. The backsheet 30
is preferably embossed and/or matte finished to provide a more clothlike
appearance. Further, the backsheet 30 may permit vapors to escape from
the absorbent core 28 while still preventing exudates from passing through
the backsheet 30.
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The size of the backsheet 30 is dictated by 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 beyond 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 periphery 38.
The topsheet 26 of the body portion 22 of the present invention is
compliant, soft feeling, and non-irritating to the wearers skin. Further, the
topsheet 26 is liquid pervious permitting liquids to readily penetrate through
its thickness. A suitable topsheet 26 may be manufactured from a wide
range of materials such as porous foams, reticulated foams, apertured films,
natural fibers (e.g. wood or cotton fibers), synthetic fibers (e.g., polyester
or
polypropylene fibers) or from a combination of natural and synthetic fibers.
Preferably, it is made of a hydrophobic material to isolate the wearer's skin
from liquids retained in the absorbent core 28.
A particularly preferred topsheet 26 comprises staple length polypropylene
fibers having a denier of about 1.5, such as Hercules Type 151
polypropylene fibers marketed by 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 may be used to
manufacture the topsheet 26. For exampie, the topsheet 26 may be woven,
non-woven, spunbonded, carded, hydnoformed or the like. A preferred
topsheet 26 is carded and thermally bonded by means well-known to those
skilled in the fabric art. Preferably, the topsheet 26 has a basis weight from
15 to about 30 grams per square meter, a minimum dry 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 any
suitable manner as is well known in the diaper manufacturing art. As used
herein, the term "associated" encompasses configurations whereby the
topsheet 26 is directly joined to the backsheet 30 by affixing the topsheet 26
direcdy to the backsheet 30, and configurations whereby the topsheet 26 is
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indirectly joined to the backsheet 30 by affixing the topsheet 26 to
intermediate members which in tum are affixed to the backsheet 30. In a
preferred embodiment, the topsheet 26 and the backsheet 30 are joined
directly to each other in the diaper periphery 38 by a flap attachment means
56 such as an adhesive or any 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 layer of adhesive, a pattemed layer 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 periphery 38
of the body portion 22, preferably 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 may comprise any of several means as are
well known in the diaper art, a particularly 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 comprises a front waist elastic element 89, which in figure 1
is formed by the elastic landing member 64. The front waist elastic element
89 preferably extends between 5 % and 60 % at a force of between 30 and
280 g per inch, preferably about 30 % at a force of 150 g per inch and
contracts the front waist region 94 in gathers to provide an elasticated fit
of
the waist region 94 against the waist of a wearer.
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Generally, the front waist elastic element 89 may be located on the
garment-facing side or on the user-facing side of the topsheet 26 and the
backsheet 30, or may be comprised between the topsheet and the
backsheet.
The diaper 20 is provided with a fastening system 24 for forming a side
' closure. By applying the hook-type fastening members 58 to the loop-type
landing member 64, 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 wom.
In a preferred embodiment of the present invention as shown in Figure 1,
the fastening system 24 comprises a fastening member 58, preferably
comprising a tape tab 60 and a hook-type fastening element 62, disposed
adjacent each longitudinal side 40 of the body portion 22 in the back waist
region 98 of the first end region 48; a landing member 64, engageable with
the hook-type fastening element 62, disposed on the outside surface 46 of
the body portion 22 in the front waist region 94. Additional
fastening/disposal means 68 may 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 member 58 may comprise a combination of a hook-type
fastening element and adhesive attachment means positioned on the body
portion 22 of the diaper 20. The hook-type fastening element 62 of each
fastening member 58 is joined to the body portion and preferably covers an
area 25 mm wide (i.e., generally perpendicular to the longitudinal centerline
29) by 62.5 mm long (i.e., generally parallel to the longitudinal centerline
29) at the panels 51 of the body portion 22. An exemplary embodiment of a
hook-type 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.
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As shown in Figures 1 and 2, the fastening member 58 most preferably
comprises a tape tab 60. Any of the well known configurations and
constructions of a tape tab may be used. A preferred tape tab 60 is a Y-
shaped tape tab as described in detail in GB-A-1458566. Altematively
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 generally correspond to the garment-facing side 44 of the body portion
22. The backing surface 72 is that surface opposite of the fastening surface
70 and generally corresponds to the outside surface 46 of the body portion
22. The backing surface 72 is thus generally 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 body
portion 22 to create a manufacturers 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 users end i.e., that joint
made by 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 body portion 22. The second fixed portion
76 is that portion of the tape tab 60 which is attached to the garment-facing
side 46 of the body portion 22. The first fixed portion 74 and the second
fixed portion 76 thus form the manufacturers end of the tape tab 60. The
connective portion 78 is that portion of the tape tab 60 which is attached to
another portion of the diaper 20, generally the landing member 64 by the
user when securing the diaper 20 on the wearer. The connective portion 78
thus forms the user's end. Additionally, the outer surface of the second fixed
portion 76 and the outer surface of the connective portion 78 form the
backing surface 72 of the tape tab 60 while the inner surface of the first
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fixed portion 74 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 body 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 body portion 22. These tab attachment means are any of those
attachment means which provide an adequate bond, and preferably are any
of the pressure-sensitive adhesives well-known to those of ordinary skill in
the adhesive art. The outer surface of.the first fixed portion 74 is affixed
to
the user-facing side 44 of the.body portion 22 by 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 body portion 22 by a second tab attachment
means 82. The connective portion is provided with a first fastening element
62 joined to it preferably by the second tab attachment means 82
(altematively, 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 may be placed on the first fastening element 62
separately 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 Company, St. Paul, Minnesota. The
tape material in the embodiments are preferably a polyethylene film having
a tab attachment means tailored to bond to the polyethylene positioned on
the tape material. The tape tab attachment means may comprise any of
those adhesives which provide an adequate bond with other portions of the
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diaper, and is preferably any of the pressure-sensitive adhesives well-
known to those of ordinary 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 Company, St. Paul,
Minnesota.
As shown in Figure 2, the tape tab 60 may also have a grip tab 83 at the
distal edge 71 in the connective portion 78. The grip tab 83 may be formed
by folding over a small margin of the distal edge 71 of the connective
portion 78 and attaching it to itsetf. This forms an end on the connective
portion 78 which is easier to grasp by 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-type 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 may comprise any
shapes as are known in the art so long as they are adapted to engage a
complementary second fastening element 66. As shown, the hook fastening
material 84 preferably 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 eiements 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 badcsheet, which fibrous material may for instance be formed by the
topsheet 26 or by a waist shield 91. Thus, the hook fastening material 84
may be manufactured from a wide range of materials. Suitable materials
include nylon, polyester, polypropylene, or any 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
commercially available material designated "Scotchmate brand No. FJ3402
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available from Minnesota Mining and Manufacturing Company, St. Paul,
Minnesota. Altematively, the engaging elements may have any shape such
as hooks, 'Ts" or any other shape as are well known in the art. A
particularly preferred hook fastening material is described in
CA 1,286,852.
Other suitable hook-type materials for use in the present invention are for
instance extruded hooks available under the reference MC5 from the
Minnesota Mining and Manufacturing Company, ST. Paul, Minnesota or
printed hooks available from the same company under references CS200
and MCS. Other suitable hook-type 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-type material such as for instance
the fibrous topsheet material.
As used herein, the term " loop-type" material is intended to mean any
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, or in a disposal configuration. A suitable loop-type
material is described in US-A-5,326,612 (Goulait).
Other suitable loop-type materials for use in the present invention may
comprise woven materials such as brushed loops available from Texmaille
S.A., Rue Pasteur, 02610 Moy de L'aisne, France; double knit loops
available from Tissages do Quintenas S.A., Parc d'activites de marenton,
B.P.158-07104 Annonay, France; and Linertess loops available under
reference LLL from the Minnesota Mining and Manufacturing Company.
Again other suitable loop-type materials are formed by non-woven
materials.
In general, the materials of the hook-type fastening members 58 and the
loop-type landing member 64 should be selected such that the peel force of
a 30 mm wide patch of hook-type material is between 3 and 20 N,
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preferably about 7-8 N and the shear force of a patch of hook-type material
of dimensions of 30 x 13 mm is between 10 and 100 N, preferably about 50
N.
The tests for measuring the.peel forces and the shear forces exerted by the
hook-type fastening members 58 on the loop type landing member 64 are
described below.
1. 1350-Peelforce Test
This method describes the procedure for measuring the peel force, in
grams, of the combined hook-type fastening member and loop-type landing
member. The materials under test are mounted on a steel plate-sled
assembly and are separated at a constant peel angle of 1350.
During the test the temperature is maintained at 73 + 20 F. The relative
humidity is controlled at 50 + 2 %.
A patch of loop-type 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-type material.
A patch of hook-type 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-type material
are angled with respect to the tape tab, the hooks are oriented to be
inclined towards the leading edge.
The hook-type material is placed on the loop- type landing member.
Subsequently, 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).
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The steel plate with the ~tached hook-type and loop-type 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 olate is slidably mounted in a sled which is carried by the lower
jaw of the INSTRON apparatus.
The leading edge of the tape tab 60 is placed in the upper jaw of the
INSTROVapparatus.
The upper cross head is set in motion to pull the leading edge of the tape
tab 60 off the loop-type landing member at an angle of 1350 with respect to
the loop-type landing member. The steel test plate on which the loop-type
landing member is mounted, is moved in the sled consecutively with the
cross head relative to the lower jaw to maintain a constant angle of 1350
during the full cycle of peeling off the tape tab.
The peak force, in grams, is recorded for at least four samples and is
averaged.
111. 1800 Shear Test
This method describes the procedure for measuring the shear force, in
grams, of the combined hook-type fastening member and loop-type landing
member. The materials under test are mounted. on a steel plate and are
separated at a constant peel-angle of 180 .
Dyring the test the temperature is maintained at 73 + 2 F. The relative
humidity 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.
~ ~ '
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A patch of hook-type material measuring 1 in. x 0.75 in. is attacned 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. ff the hooks of the hook-type material
are angled with respect to the tape tab, the hooks are oriented to be
inclined away from the leading edge.
The hook-type material is placed on the loop-type landing member.
Subsequently, 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-type and loop;4Xpe materials is
mounted horizontally 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 Ieadin edge of the tape tab 60 is placed in the upper jaw of the
fNSTROfJ apparatus .
The upper cross head is set in motion to pull the leading edge of the tape
tab 60 off the loop-type landing member at an angle of 1850 with respect to
the loop-type landing member. When the maximum pull force has been
reached, the crosshead is retumed to the pre-set gage length.
The peak force, in grams, is recorded for at least four samples and is
averaged.
Figures 3 to 7 show cross-sectional views of different embodiments of the
front waist region 94 of the diaper of figure 1 along a line or cross-section
parallel to the front transverse edge 42' and running through the front waist
elastic member 89. In figures 3-6, the front waist section 94 is shown in its
flattened state, i.e. the elastic elements 89 in the front waist region 94 are
stretched.
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In the embodiment of figure 3, the landing member 64 is made of an elastic
loop-type material, which may be an elastic non-woven material or which
may be a loop-type materiai comprising elastic strands or elastic fibers. The
landing member 64 is located on the garment-facing side 46 of the
backsheet 30 and forms the front waist elastic element 89.
Figure 4 shows an embodiment wherein the landing member 64 comprises
a laminate of an elastomeric film 96 and a loop-type material 97. The loop-
type material 97 is bonded to the film 96 for instance by adhesive bonding
or by ultrasonic bonding. A suitable film is available from EXXON as type
no. 500 a suitable loop-type material is available from Amoco as fabric type
no. P8. The laminate 96,97 may be formed by attaching the loop-type
material 97 to the elastomeric film 96 while the film is in a pre-stretched
state, such that the loop-type material is contracted by the film 96 to form
gathers. Altematively, the laminate 96,97 may be formed by attaching the
loop-type material 97 to the film 96 while the film is in its relaxed state.
Such
a laminate material may be activated, to impart extensibility thereto prior to
attaching it to the topsheet or the backsheet, or after attaching it to the
topsheet or backsheet, by mechanically deforming the fibrous layer 97 by
drawing it, or by passing it through a pair of corrugated rolls. By such a
treatment, a number of fibers of the layer 97 will break or will become
disentangled, so that this layer becomes extensible in the direction of the
front transverse edge 42'. Mechanically activating a so-called "zero strain"
elastic laminate has been described in European patent application no.
93117656.4 and in US-A-5,196,000 and US-A-5,236,430.
Another type of elastic laminate comprises a fibrous layer 97 attached to a
film 96, which film is heated such that it elastically contracts to form an
elastic laminate.
In the embodiment of figure 5, the front waist elastic element 89 is
connected to the user-facing side 44 of the topsheet 26. The landing
member 64 is connected to the garment-facing side 46 of the backsheet 30,
and is contracted by the elastic element to form transverse gathers, which
run generally perpendicular to the front transverse edge 42. The landing
member 64 is in itself non-elastic, but is elastically extensible by at least
5
%, preferably by at least 30 ~.
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In the embodiment of figure 6, the elastic element 89 is sandwiched
between the topsheet 26 and the backsheet 30. The landing member 64 is
located on the garment-facing side 46 of the backsheet 30.
In the embodiment of figure 7, the elastic element 96 is shown in its relaxed
state, the backsheet 30 and the landing member 64 being gathered by the
contracted elastic element 96. Instead of the gathers in the topsheet 26 and
the backsheet 30 being caused by contraction of the elastic element 96, the
corrugations as shown in figure 7 may also have been imparted by passing
the backsheet 30, the loop-type material 97 and the elastic film 96 through a
pair of intermeshing grooved rolis while the elastic film 96 is in its relaxed
state, as described in US-A-5,236,430.
Figure 8 shows an embodiment wherein the backsheet 30 comprises cut-
out sections 90 in the front waist region 94. The topsheet 26 is exposed at
the garment-facing side 46 of the backsheet 30 in the region of the cut-out
sections 90 to form the landing member 64. The elastic element 89
contracts the topsheet in transverse gathers, which will cause the fibers of
the topsheet 26 to stand away from the topsheet surface and which wilt
cause parts of the topsheet 26 to project outwardly from the cut-out sections
90. This will improve the fastening of the hook-type fastening member 58 to
the landing member 64.
Figure 9 shows a cross-sectional view of the front waist region 94 of the
diaper of figure 8 along a line or cross-section parallel to the front
transverse edge 42' and running through the front waist elastic member 89.
The cut-out sections, or holes, 90 through the backsheet 30 expose the
topsheet 26 which forms an inner layer on the user-facing side 44 of the
backsheet 30 which can engage with the hooks of the fastening member 58.
In the embodiment of figure 10, and additional layer 92 is located between
the topsheet 26 and the backsheet 30. The layer 92 may for instance be a
polyethylene film, located between the topsheet and the core 28 along the
front transverse edge of the core to prevent leakage therefrom, the layer 92
being in this case a so-called "waist shield". Altematively, the layer 92 may
be a tissue underlying the core and being co-extensive with the backsheet
30. In again another embodiment, the inner layer 92 is co-extensive with the
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backsheet 30 and is laminated to the user-facing side 44 of the backsheet
30, and may comprise a thermoplastic film. In this case the backsheet 30 is
preferably formed by a non-woven layer, which provides a soft and cloth-
like garment-facing surface 46. In case the inner layer 92 is unsuitable for
becoming mechanically attached to the hook-type fastening members 58,
the cut-out sections 90 extend through the inner iayer 92 up to the inner
layer which is adapted to entangle with, and to attach to the hook-type
fastening members 58.
Figure 11 shows a cross-sectional view of the front waist region 94 along a
line of cross section parallel to the front transverse edge 42', wherein an
elastic laminate 96,97 is comprised along the front waist edge 42' between
the topsheet 26 and the backsheet 30. The laminate comprises a nonwoven
layer 97 and an elastomeric film 96 attached to the nonwoven layer 97. The
elastic laminate contracts the front waist edge 42' in a number of gathers
such that the fibers of the layer 97 project outwardly into the apertures 90.
Figure 12 schematically shows a plan view of the garment-facing side of an
absorbent article 20 wherein the landing member 64 is comprised of a
single strip-shaped aperture in the backsheet 30 alongside the front
transverse edge 42'. In the embodiment of figure 13, the landing member 64
comprises a number of individual cut out regions 99,100,101 and 102
located in the front waist region 94.
Figure 14 shows an embodiment wherein the front transverse edge 42' of
the backsheet 30 is curved. The cut-out sections 103, 104 are placed at an
angle with respect to that front transversed edge 42' to receive the angled
fastening members 58. An absorbent article of this shape fits well below the
belly of the wearer and will be located in the low-motion zone of the wearer.
Hence the front waist region 94 will be subject to iittle movement and will
stay properly in place.
The fastening members 58 may comprise a loop-type material 68 on their
backing surface 72, as shown in figure 1. This has as an advantage that the
closure members 58 can be used to mutually engage for keeping the diaper
20 in a rolled-up disposal configuration as described in EP-A- 321 234 .
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In the embodiment of figure 15, the backsheet 30 comprises a front
transverse edge 42' which is located below the topsheet 26 inboard from
the front transverse edge 42" of the topsheet 26. The backsheet 30 does
not extend into the landing zone 61, which is defined by the garment-facing
surface to which the hook-type fastening members 58 can attach when the
article 20 is placed on a wearer. The topsheet 26 extends beyond the front
transverse edge 42' of the backsheet and forrns the landing member 64.
The front waist elastic element 89 is connected to the user-facing side 44
of topsheet 26.
Figure 16 shows a cross-sectional view of the absorbent article of figure 15
along the longitudinal center line 29. The elastic element 89 is located on
the garment-facing side 46 of the topsheet 26, and is for instance formed by
a laminate of an elastomeric film 96 and a fibrous layer 97 to which the
hook-type fasteners may engage. In this case the underlying topsheet
material may be comprised of an apertured plastic film or of a fibrous
material which is in itself unsuitable for attachment to the hook-type
fastening members 58.
In figure 17 it is depicted that the elastic member 89 is located on the user-
facing side 44 of the topsheet 26, as is also shown in figure 1. Figure 18
depicts an embodiment wherein an inner layer 91 forms a waist shield
against leakage of exudates from the front transverse edge 59 of the core
28. The inner layer 91 projects beyond the front transverse edge 59 of the
core 28 and beyond the front transverse edge 42' of the backsheet 30 and
forms the fastening member 64. In the embodiment of figure 19, the elastic
element 89 is comprised between an inner layer 91, which is co-extensive,
but not coterminous with the backsheet 30 and the topsheet 26. The inner
layer 91 in this case may be a core-reinforcement layer or may be a non-
woven inner layer, laminated to the backsheet 30. The elastic element is
comprised between the inner layer 91 and the topsheet 26.
Figure 20 shows an embodiment wherein the backsheet 30 comprises a
curved front transverse edge 42' which defines the contour of a waist panel.
The inner layer 91, which is uncovered by the backsheet 30 in the front
waist region 94, forms the landing member 64. The inner layer 91 extends
between edge 93 and front edge 42". In figures 21 and 22, a cross-
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sectional view along the line 20-20 of figure 20 is shown. The inner layer 91
may be made of an elastic material and may be flat, i.e. without gathers, as
shown in figure 21. In this case the front waist elastic element 89 is formed
by the elastic layer 91.
Altematively, the inner layer 91 is in itself non-elastic, but is contracted
along a number of transverse gathers by a separate front waist elastic
element 89, as shown in figure 22. The transverse gathers causes the fibers
of the inner layer 91 to stand-up and project outwardly and thereby increase
the fastening capacity of the hook-type material thereto. The transverse
gathers may be formed by elastic contraction of the elastic material 87.
Altematively, the transverse gathers may be obtained by mechanical pre-
straining of the inner layer to form parallel corrugations. In case the pre-
straining imparts a degree of elasticity to an originally non-elastic web, the
front waist elastic member 89 may be omitted, the pre-strained inner layer
91 forming the waist elastication.
Figure 23 shows a partial enlarged plan view of a pre-strained inner layer
91 in the front waist region 94. The inner layer 91 comprises a number of
parallel corrugations 120, 121. In case the inner layer 91 is not elastically
extensible, these corrugations 121,122 impart a degree of elastic
extensibility of between 0- 50 %, preferably between 10 % and 20 % to the
layer 91. Additionally, the mechanical treatment of the inner layer 91 by
which the fibers of the inner layer become disentangled to a larger or
smaller degree in the process of forming the corrugations 120,121, will tend
to improve the surface texture of the inner layer 91 for improved fastening of
the hook-type material thereto. The process for imparting such surface
structure has been described in detail in US-A-5,196,000
and CA 2,176,202.
Figure 24 shows an embodiment wherein the inner layer 91 comprises a
number of. parallel corrugations 120,121 and forms an elasticated waist
panel in the front waist region. In one embodiment, the layer 91 in figure 24
is a laminate of a non-elastic non-woven layer such as the polypropylene
fibrous topsheet material and a non-elastic thermoplastic film, such as the
polyethylene backsheet film.
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In the embodiment of figure 25, the backsheet 30 comprises a first
backsheet section 31 and a second backsheet section 31'. The first and
second sections are mutually attached in the region of a front peripheral
edge 43 of the first backsheet section 31. The front backsheet section 31'
extends into the landing zone 61, which is indicated in figure 25 by dashed
line 49. The front backsheet section 31' comprises a loop-type material for
engaging with the hook-type fasteners 58. The front backsheet section 31'
may be comprised of an elastic non-woven material or may comprise an
extensible, non- elastic material which is gathered by a front waist elastic
element 89.
Figure 26-28 show cross-sectional views of different embodiments of the
absorbent article of figure 25, along the longitudinal centerline 29. The
front
backsheet section 31' is attached to the backsheet section 31 with
attachment means 65, which may be adhesive, ultrasonic or heat-seal
attachment means. The backsheet section 31 terminates at front peripheral
edge 43, which is located outboard from the landing zone 61. The front
backsheet section 31' is attached to the garment-facing side 46 of the
backsheet section 31. In the embodiment of figure 26, the backsheet
section 31 underlies the absorbent core 28 and is made of a liquid-
impervious thermoplastic film, the front backsheet section 31' being made of
a breathable elastic non-woven material.
In the embodiment of figure 27, a front waist elastic element 89 is located
on the user-facing side 44 of the second section 31' of the backsheet 30.
The first backsheet section 31 extends beyond the perimeter of the
absorbent core 28, the second backsheet section 31' being connected to
the user-facing side 44 of the first section 31.
In the embodiment of figure 28, the topsheet 26 extends across the front
backsheet section 31. An elastic element 89 is encased between the
topsheet 26 and the front backsheet section 31'.
Figure 29 shows an embodiment wherein the landing member 64
comprises the topsheet 26, the backsheet 30 and the waist elastic element
89 comprised between the topsheet and the backsheet. The topsheet 26,
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and the backsheet 30 are folded around fold line 41. The doubled-over
combination of the topsheet 26, backsheet 30 and elastic member 89, forms
an elastically extensible landing member 64. The front transverse edge 42'
of the backsheet 30 is maintained in a folded-over configuration by the
fastening means 95, which may be formed by one or more glue beads, and
which attach the doubled-over front waist region 94 to the garment facing
side 46 of the backsheet 30.
In the embodiment of figure 30, the waist elastic element 89 is located
between the topsheet 26 and the backsheet 30, and is folded in its entirety
around the fold line 41. The topsheet 26, backsheet 30 and waist elastic
element 87 are mutually attached by spiral adhesive pattems
125,126,127,128 and 131.
In the embodiment of figure 31, the elastic element 89 is located on the
user-facing side 44 of the topsheet 26. The elastic element 89 may in this
case be comprised of a stretchable non-woven material, which is adapted to
engage with the hook-type fastening members. Altematively, the elastic
element 89 comprises a laminate of an elastomeric film 96 and a non-woven
layer 97 attached to the elastomeric film. The elastomeric film 96 of the
elastic laminate is attached to the topsheet 26, the non-woven layer 97 of
the elastic laminate being placed on the user-facing side 44 of the topsheet
before folding around the fold line 41. When the front waist section 94 is
doubled-over around fold line 41, the non-woven layer 97 of the elastic
laminate will be located on the garment-facing side of the backsheet facing
outwardly and forming the landing member 64.
In the embodiment of figure 32, the elastic element 89 comprises a region
110 which is unattached to the underlying topsheet layer 26. Upon
doubiing- over of the topsheet 26 and the backsheet 30 along the fold line
41 in the front waist region 94, the unattached segment 110 of the elastic
element 87 protrodes outwardly and forms a flexible and elastic waist panel,
which will contact the stomach of the wearer during use.
The inner layer which after doubling-over of the front waist region 94 forms
the landing member 64 may altematively be formed by a layer which
underlies the core, similar to layer 91 as shown in figure 19, and which is
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co-extensive with the user-facing side 44 of the backsheet 30. Such an
inner layer 91 may be a core-reinforcement layer or may be the lower layer
of an envelope layer which enwraps the core 28.
Altematively, the topsheet 26 may extend beyond the front transverse edge
42' of the backsheet, and may be doubled over along the front transverse
edge 42' to form the landing member, as shown in figure 36.
In the embodiment of figure 33, a number of cuts 111,112,113 extend
through the backsheet 30 and the inner layer on the user facing side 44 of
the backsheet 30 from the front transverse edge 42' towards a fold line 41.
A number of sections 114,115,116 and 117 are formed between each pair
of neighbouring cuts. The backsneet 30 and inner layer of each section are
folded along the fold line 41 to obtain a low-cut front waist region. The fold
line 41 in figure 33 forms an inwardly concave cut in the front waist region
94. Such a curved front waist section fits well in the low motion zone below
the belly of a wearer.
In the embodiment of figure 32, only two cuts 111,112 are provided in the
backsheet 30 and material such that a single flap is obtained in the front
waist region, which is folded over along fold line 41. The folded over
sections 114,115 and 117 and the folded-over flap in figure 34 may
comprise any the material of the inner layer 91, in case the inner layer 91
extends beyond the front transverse edge 42' of the backsheet 30.
In the embodiment of figure 35, the cuts 111,112,113 extend
perpendicularly to the front transverse edge 42' of the backsheet 30. Each
cut 111,112,113 ends at a fold line 41 which is parallel to the front
transverse edge 42'. The doubled over sections 114,115,116 form a
steppid waist section, which may be cut along a contour 115 to obtain an
inwardly concave waist section.
In the embodiment of figure 36, the topsheet 26 extends beyond the front
transverse edge 42' of the backsheet 30, the front transverse edge 42'
forming the fold line 41. The topsheet 26 and the backsheet 30 in the front
waist tegion 94 are provided with a number of corrugations 120,121, as
shown in figure 23. No additional elastic elements are applied in the front
CA 02325556 2000-12-01
WO 96/25133 PCT/US96/01194
waist region 94, elasticity being provided by the corrugated topsheet and
backsheet layers of the landing member 64.
Figure 37 shows the absorbent article 20 having a landing member as
shown in figure 32 when put on a wearer. The article 20 comprises rounded
sections 123 of the longitudinal sides 40. The rounded sections 123 match
with the upper edge 126 of the elastic element 89 and form a rounded
contour. Additional patches of hook-type 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 hook-type material 122 helps to maintain the front and back end
regions 48,50 in a properly overiapping relationship on the wearer.
