Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 0224483~ 1998-07-31
W O 9713160Z PCTrUS97/01660
DUAL ELASTIC, LIQUID BARRIER CONTAINMENT FLAPS FOR A DISPOSAB~E
ABSORBENT ARTICLE
Back~round of the Invention
The present invention relates to disposable absorbent articles, and more particularly to
10 disposable absorbent articles having dual elastic, liquld barrier containment flaps for
improving waste containment.
~isposable absorbent products have been designed and used for various purposes. For
example, some have been designed for use as diapers for babies, some as training
15 pants for younger children generally between the age of 1~ months to 36 months, and
some as incontinence products for adults. One of the most important functions o~ any
disposab~e absor~ent product is the containment of liquid and other waste material.
Failure to do so results in leakage and wetting of the clothes, both of which are highly
undesirably to ~he wearers and caregivers.
Most of these disposable absorbent products are multi-layer designs having a liquid
impermeable outer layer, a liquid permeable inner layer, and an absorbent therebetween.
There may be additional components, such as containment flaps, additional layers of
absorbent material, elastic materials, or the like. In many of these products, the sides or
25 edges of some of the layers are coincident, and this can cause a problem in accurately
CA 0224483~ 1998-07-31
W O 97/31602 PCTAUS97/01660
registering or positioning other components relative to the coincident layers. This is due
to the weaving of the layers as they proceed through the manufacturing process, and is
generally termed "web weave." Other problems relating to this lack of web weave
tolerance include inaccurate application of adhesive to or between layers or co"l~onents,
5 the necessity of applying excessive amounts of adhesive, or the like.
Ultimately, any one of these problems, or a co,llb;. ,dlion, can cause undesired tearing or
separation of layers or components in the products, increased cost in manufacture or
materials, undesired exposure of layers or components, inferior waste conl~i"ment, or
lû the like. In view of this, it is apparent that there exists a need for improving waste
conlai. ~I ~ ,ent.
SummarY of the Invention
In response to the discussed difficulties and prublen.s encountered in the prior art, a
15 ~~is~os~hle absorbent article having improved waste conldi"",enl features has been
discovered.
in one form of the present invention there is provided a disposable absorbent article
including a liquid impermeable backsheet and an absorbent structure on the backsheet.
20 A liquid barrier zone is defined by the backsheet on each side of the absorbent structure,
and both liquid barrier zones extend between a front edge and a back edge of the
backsheet. A liquid impermeable conLdi"~,ent flap having an inner edge and an outer
edge is over each liquid barrier zone, and has a flap elastic member and a leg elastic
member elas~ically associated therewith. A liquid barrier is in each liquid barrier zone
2~ between the liquid impermeable conlai""~ent flap and the liquid impermeable backsheet,
and extends between the front edge and the back edge of the backsheet.
.
CA 0224483~ 1998-07-31
W O 97/31602 PCTrUS97/01660
In another form of the present invention there is provided a disposable absorbent article
including a liquid impermeable backsheet an absorbent structure and a liquid barrier
zone defined by the liquid impermeable backsheet on each side of the absorbent
structure. Both liquid barrier zones extend between a front edge and a back edge of the
5 liquid impe""~Ptle backsheet and a conlai",~,ent flap having a liquid impe""eable inner
layer and an outer layer is over each liquid barrier zone. A flap elastic member and a leg
elastic member are positioned between the inner layer and outer layer of each
conl~;. ""ent flap and a leg elastic member is positioned between the inner layer and the
outer layer of each conL~;"~e~ ll flap. A liquid barrier is in each liquid barrier zone
10 between the liquid impermeable inner layer and the liquid impermeable backsheet and
extends between the front edge and the back edge of the backsheet.
In still another form of the present invention there is provided a disposable absosl,enl
article including a pant body having a waist opening periphery a pair of leg opening
15 peripheries and an interior space. The pant body further includes a liquid impermeable
backsheet having a front edge and a back edge that are sul,slanlially contiguous with the
waist opening periphery. An absorbent structure is in the interior space and a liquid
barrier zone is defined by the liquid impermeable backsheet on both sides of the
absorbent structure in which each liquid barrier zone extends between the front edge
20 and the back edge of the backsheet. A liquid impermeable conl~i""lent flap is over each
liquid barrier zone and inciudes a flap elastic member and a leg elastic member
elasLic-.lly associated therewith. A liquid barrier is In each liquid barrier zone between the
liquid impermeable conlail ~ ent flap and the liquid impermeable backsheet and extends
between the front edge and the back edge of the backsheet.
CA 0224483~ 1998-07-31
W O97f31602 PCT~US97/01660
Brief Descriplion of the Drawinqs
The above-mentioned and other features of the present invention and the manner of
attainin~ them will become more apparent, and the invention itself will be better
understood by reference to the foilowing description of the invention, taken in coniunctlon
5 with the accol."~anying drawings, wherein:
Fig. 1 iliustrates a front perspective view of one type of r~i~pQs~hle absorbent article
incorporating the principles of the present invention;
1Q Fig. 2 illustrates a top plan, partially ~;sassenlL)led viewof the article in Fig. 1;
Fi~. 3 illustrates a cross-sectional view of Fig. 2 taken along line 3-3 and viewed in the
direction of the arrows;
15 Fig. 4 illustrates a frayllleilldry view of a ",odiricdlion of the view in Fig. 3; and
Fig. ~ illustrates a fragmentary view of another modificalion of the view in Fig. 3.
Detailed Desc~i~,liol1
20 The principles of the present invention can be incorporated into any sl l'~ ~ Ie disposable
absor~ent article. Examples of such sl " ' le articles include diapers for babies, training
pants for children, and incontinence products for adults. 'For ease of explanation, the
descrip,'ion hereafter will be in terms of a child's training pant.
25 Referring to Fig. 1, there is illustrated a disposable absorbent article, such as a training
pant 10, comprising a pant body 12 including a front panel 14, a back panel 16, and a
CA 0224483~ l998-07-3l
W O 97t31602 PCTAUS97/01660
crotch panel 18 interconnecting front panel 14 with back panel 16. A pair of tearable,
non,~t,d~,~enable side seams 20 join selected portions of front panei 14 and back panel
16 to define an interior space 22, a waist opening periphery 24, and a pair of leg opening
peripheries 26. The term "disposable" means that the described article is designed to be
5 used until soiled, either by urination, defecation, or othe~vise, and then discarded rather
than being washed and reused. The term "pant body" refers to an article that has a waist
opening and a pair of leg openings similar to shorts, swim wear or the like.
Referring primarily to Figs. 2-3, training pant 10 comprises in major part a liquid
permeable topsheet 28, a liquid impermeable backsheet 30, an absorbent structure 32
between topsheet 28 and backsheet 30, a pair of liquid impermeable containment flaps
34, and elastic side panels 36. The liquid impermeable backsheet 30 desirably has a
width greater than that of the liquid permeable topsheet 28, in which the width dimension
is measured along a line perpendicular to centerline 38 (Fig. 2). Because the topsheet
~5 28 is narrower than the backsheet 30, a portion or zone of the liquid impermeable
backsheet 30, on each side of the absorbent structure 32, is exposed along the full
length thereof, in which the length dimension is measured in a direction parallel to
centerline 38. Generally, each exposed zone, hereinafter referred to as a liquid barrier
zone, has a width of about 2 millimeters or greater, a desired width o~ about 4 l~lilli."eLe"
20 or greater, and a more desired width of about 6 millimeters or greater.
With reference to Fig. 3, backsheet 30 is illustrated wider than topsheet 28, which
noticeably compares with those current disposable absorbent products that have their
various layers generally coincident. In these current products, there is very little, if any,
25 tolerance for web weave, which is the uncontrolled, erratic movement of a layer or web
as it continuously moves at high speeds through a manufacturing process. Although
CA 0224483~ 1998-07-31
WO 97/31602 PCTrUS97/~166
various devices, such as dancer roles, feed controls, and the like, have been used to
minimize web weave, there is still a measurable amount of undesirable weave in those
processes. With current disposable absorbent products, because the layers are
cci. ,-,;denL, or at least very close together along their sides or edges, this low tolerance
5 for web weave results in adhesive lines being applied outside of their desired positions,
such that they may adhere wrong components together, or fail to adhere the correct
components together.
As illustrated in Fig. 3, one of the advantages of the present invention is the exposed
10 liquid barrier zones between the topsheet 28 and backsheet 30 that provide increased
tolerances for accol"l"odating web weave, thereby improving proces~ "'y in the
manufacturing process. This web weave tolerance can be further increased by
~'11- Idlill9 topsheet 28 in those disposable absorbent articles that do not necess~rilr
re~uire a topsheet. Due to the increased web weave lc,lerdnce, components now have a
15 wider attachment or positioning area. For e~c~mple, since backsheet 30 is relatively
wider, the elastic side panels 36 can now be spaced farther apart in the width di, e-,liul 1.
This permits the elastic side panels 36 to be made more narrow in width, since they now
are spaced farther apart on either side of absorbent structure 32. This results in a
sig";ricanl reduction in cost, since the ",ale-ials of which elastic side panels 36 are made
20 are expensive compa~ed to the other materials in training pant 10.
The increased web weave tolerance also provides wider areas of ~ppli ~ on of bon dli~ ,es
for joining various components together. This greatly ~ l;.lli es or eli."inales a bondline
failing to join the correct components together, or undesirably joining wrong components
25 together.
CA 0224483~ 1998-07-31
W O97131602 PCT~US97/0166
Still another advantage of the present invention is that a wider absorbent structure 32
can be placed with a wider backsheet 30, thereby providing increased absorbent
capacity. These advantages, along with others, will be described in greater detail
hereafter.
The liquid impermeabie backsheet 30 has a front edge 40 (i~ig. 2) subslal ,liaily
contiguous with waist opening periphery 24 (Fig. 1), a back edge 42 subslanlially
contiguous with waist opening periphery 24, and a pair o~ side edges 44. The term
"liquid impermeable", when used in describin~ a layer or multi-layer lcl",inale, means that
10 a liquid, such as urine, will not pass through the layer or laminate, under ordinary use
conditions, in a direction generally perpendicular to the plane of the layer or lar"i"aLe at
the point of liquid contact. Liquid, or urine, may spread or be ll dnsiaol led parallel to the
plane of the liquid impermeable layer or laminate, but this is not considered to be within
the meaning of "liquid impermeable" when used herein. Backsheet 30 can be a single
15 layer of liquid impermeable material, or can be a multi-layered laminate structure in which
at least one of the layers is impermeable to liquid. As illustrated in Fig. 3, liquid
imperrneable backsheet 30 includes a liquid permeable outer ~ayer 46 and a liquid
impermeable inner layer 48 that are suitably joined together by a laminate adhesive 50.
Laminate adhesive 50 can be applied continuously or intermittently as beads, a spray,
20 parallel swirls, or the like. Suitabie adhesives can be obtained from Findley Adhesives,
Inc., of Wauwatosa, Wisconsin, or from National Starch and Chemical Company,
Bridgewater, New Jersey. Liquid permeable outer layer 46 can be any sl ~it~hle I l Idlel ial
that provides a generally cloth-like texture. One example of such a material is a 20 gsm
~grams per square meter) spunbond polypropylene nonwoven web. C)uter layer 46 may
25 also be made of those materials of which liquid permeable topsheet 28 is made. Further,
CA 0224483~ 1998-07-31
W O97131602 PCT~US97/01660
it is not a necessity for outer layer 46 to be liquid permeable but it is desired that it
provides a relatively cloth-like texture to the wearer.
The inner layer 48 of backsheet 30 can be both iiquid and vapor impermeable or can be
5 liquid impermeable and vapor permeable. Inner layer 48 is desirably manufactured from
a thin plastic film although other flexible liquid impermeable materials may also be used.
Inner layer 48 or liquid impermeable backsheet 30 when a single layer prevents waste
m alt:rial from wetting articles such as bedsheets and clothing as well as the wearer and
caregiver. A suitable liquid impermeable film for use as liquid impermeable inner layer
48 or a single layer liquid impermeable backsheet 30 is a 1.0 mil polyethylene film
commercially available from Edison Plastics Company of South Piainfield New Jersey. If
backsheet 3Q is a single layer of ,,I~Lerial it can be embossed and/or matte finished to
provide a more cloth-like appearance. As earlier mentioned the liquid impermeabie
r"aLeiial can permit vapors to escape from the interior of the ~I;$I.o5~hle absorbent srticle
1~ while still preventing liquids from passi.,g through the backsheet 30. A sll ' -'-'e
"breathable" material is composed of a ",~ poruus polymer film or a nonwoven fabric
that has been coated or otherwise treated to impart a desired level of liquid
impe""- "'y. A suitable microporous film is a PMP-1 film material commercially
availablefromMitsuiToatsuChemicals Inc. Tokyo Japan oranXK0-8044polyolefin
20 film coi"n~er~;idlly available from 3M Company Minneapolis Minnesota.
When backsheet 30 is a multi-layer laminate as is illustrated in Fig. 3 liquld impe".,eable
inner layer 48 includes a pair of side edges 52 and outer layer 46 includes a pair of side
edges 54. As illustrated in Fig. 3 side edges 52 are inboard of side edges 54 wherein
25 "inboard" or"outboard" is with r~r~nce to cenlell;..e 38. In this instance side edges 52
of liquid impermeable inner layer 48 correspond to side edges 44 (Fig. 2) of a single layer
CA 0224483~ l998-07-3l
W O 97/31602 PCTrUS97/01660
liquid impermeable backsheet 30. Both side edges 52 and side edges 54 can be
contiguous, but this is not a requirement of the present invention.
Referring to Figs. 1 and 3, absorbent structure 32 is positioned on backsheet 30 within
interior space 22 of training pant 10. Absorbent structure 32 can include an absorl.ent
pad 56 and a surge layer 58 suitably joined together, such as by topsheet adhesive 60.
Topsheet adhesive 60 can be any sl lit~lQ adhesive applied in any manner well known in
the art. Examples of suitable adhesives are the same as those with reference to
la~ a~e adhesive 50. Absorbent pad 56 can be any structure which is generally
10 compressible, conformable, nonirritating to the child's skin, and capable of absorbing and
retaining tiquids and certain body wastes. Absorbent pad 56 can be manufactured in a
wide variety of sizes and shapes, and from a wide variety of liquid absorbent materials
co""nonly used in the art. For example, absorbent pad 56 can cor"prise pulp fluff,
superdbso, L,ent material, or a combination of both. If in CCil I Ibi. ,~tion, the pulp fluff and
15 the superabsorbent ",aLe,ial can be blended together, or can co."~ ~ise discrele layers of
fluff and discrete layers of superabsorbent material. Various types of wettable,hydrophilic fibrous material include naturally occurring organic fibers composed of
inl~ sically wettabie materials, such as cellulosio fibers; synthetic fibers composed of
cell~ ~'ose or cell~ ~'ose derivatives, such as rayon fibers; iuo, yanic fibers composed of an
20 inherently wettable material, such as glass fibers; and synthetic fibers composed of a
nonwettable, thermoplastic polymer, such as polypropylene fibers that have been
hydrophilized by appropriate means, such as by treatment with silica, treatment with a
material which has a sl ljt~hlE: hydrophilic moiety, or the like.
25 Suitable superabsorbent materials may be organic or inorganic. Suit~hle inorganic
superabsorbent materials include, by way of example, absorbent clays and silica gels.
CA 0224483~ 1998-07-31
W O97/31602 PCT~US97/01660
Other suitable superabsorbent ~dl~ials are available from various commercial vendors,
such as Dow Chemical Company, Hoechst-Celanese Corporation, and Allied Colloids,
Inc. Typically, a superabsorbent material is capable of absorbing at least about 15 times
its weight in water, and desirably is capA~'e o~ absorbing more than about 25 times its
5 weight in water.
In one embodiment, absorbent pad 56 is generally rectangular in shape, and c~r"~,rises a
blend of wood pulp fluff and superabsorbent ~~alerial. One p~f~r,t:d type of fluff is
identified with the trade designation CR1654, available from Kimberly-Claric Corporation,
10 Neenah, Wisccjnsi", and is a bleached, highly absorbent sulfate wood pulp containing
p, i."arily soft wood fibers. The fluff and su~ e~dbsorLent llldlel ial in absorbent pad 56 are
present in a ratio of about ~ grams to about 20 grams fluff, to about 7 grams to about 14
grams superabsorbent material. The absorbent pad 56 has a density within the range of
about 0.10 grams per cubic centimeter to about 0.35 grams per cubic centimeter. The
15 absorbent pad 56 may or may not be wrapped or encomr~csed by a suitable tissue wrap
that maintains the integrity and/or shape of absorbent pad 56.
Surge layer 58 is constructed and designed p~ a~ily to receive, temporarily store, and
transport liquid along the mutually facing surface with absorbent pad 56, thereby
20 ",a,~i".i~i"g the absorbent capacity of absorbent structure 32. One sl~it~hle construction
and design of a surge layer 58 is a Illdlelidl having a basis weight of about 50 grams per
square meter, and cc",-,cri~ing a through-air-bonded-carded web of a homogenous blend
of 60 percent 3 denier bicomponent fiber ~o"~prisi~ ,9 a polyester core/polyethylene
sheath, commercially available from BASF Co" oldlion, and 40 percent 6 denier
25 polyester fiber, commercially available from Hoechst Celanese.
CA 0224483~ 1998-07-31
W O 97/31602 PCTrUS97/01660
Absorbent structure 32 is suitably joined to backsheet 30 by construction adhesive 64.
Construction adhesive 64 can, as with laminate adhesive 50, be any suitz~'e adhesive
applied in any manner well known in the art.
5 Referring to Figs. 2 and 3, liquid permeable topsheet 28 is illustrated as overiying
backsheet 30 and absorbent structure 32. Liquid permeable topsheet 28 includes a pair
of lateral edges 66 (Fig. 2~ that are inboard of, i.e., nearer to centerline 38 than, side
edges 44 of backsheet 30. Topsheet 28 is desirably compliant, soft feeling, and
l~oni"ildLing to the child's skin, and permits liquids to readily p~ LIdle through its
10 thickness. Topsheet 28 may be manufactured from a wide range of materials, such as
porous foams, retic~ ted foams, apertured plastic films, natural fibers, synthetic fibers,
or from a co",i,inaLion of natural and synthetic fibers. If topsheet 28 co,I,prises
sub:.lanlially hydrophobic material, the hydrophobic material can be treated with a
SL~I ~d~ or otherwise processed in order to impart a desired level of vvt~ bilily and
hyJ~upi-"' '~y. One such slJIra~;ldlll is a 0.28 percent Triton X-102 surfactant. A suitable
liouid permeable topsheet 28 is a nonwoven bicomponent web having a basis weight of
about 27 gsm. The nonwoven bicomponent may be a spunbond bicomponent web, or a
bonded carded bicomponent web. Suitable bicomponent staple fibers inciude a
polyethyiene/potypropylene bicomponent fiber available from CHISSO Corporation,
20 Osaka, Japan. In this particular bico",ponent fiber, the polypropylene forms the core and
the polyethylene forms the sheath of the fiber. Other fiber orientations are possible, such
as multi-lobe, side-by-side, end-to-end, or the like. Topsheet 28 is suitably joined to
absorbent pad 56 by topsheet adhesive 60, and is suitably joined to surge layer 58 by
surge adhesive 68. These adhesives can be the same type of adhesive as that used for
25 la",i"~le adhesive 50.
CA 0224483~ 1998-07-31
W O 97/31602 PCT~US97/01660
As illustrated in Fig. 1, training pant 10 has an eiastic side panel 36 disposed on each
side thereof. Each elastic side panel 36 includes a seam 20 that ul~l ~son ~ "y bonds the
two portions that forrn each elastic side panel 36. With reference to Fig. 3, each elastic
side panel 36 is suitably joined to backsheet 30 by construction adhesive 64, and is
suitably joined to a respective co, llail u~ent flap 34 by flap panel adhesive 70. As
illustrated in Fig. 3, each flap panel adhesive 70 cor"~.rises three beads, or lines, of a
sl ~-' 'e adhesive for joining each elastic side panel 36 to its respective oolllc.;.,,,,e~lflap
34. Use of the terrn "respective" describes a specific positional l~laLionshi,~ between two
elements; for example, in Fig. 3, elastic side panel 36 on the left-hand side of Fig. 3 is
10 Joined to a "respective" containment flap 34 on the same side of Fig. 3. Similar use of
the term "respective" in relation to other components, such as adhesives, elastic
members, or the like, has the same meaning.
Suit~hle 1"alerials of which elastic side panels 36 can be made, as well as one described
15 process of incorporating elastic side panels 36 into a training pant 10, are described in (i)
U.S. Patent No. 4,940,464, issued July 10, 1990; (ii) U.S. 5,224,405, issued July 6, 1993;
(iii) U.S. 5,104,116, issued April 14, 1992, and (iv) U.S. 5,046,272, issued September 10,
1991; ail of these aforementioned U.S. patents being incorporated by reference herein.
20 With reference to Fig. 3, a first liquid barrier zone 72 is posilioned on one (the left) side of
centerline 38 (Fig. 2), and a second liquid barrier zone 74 is formed on an other (the
right) side of centerline 38. More specifically, first liquid barrier zone 72 is on one side of
absorbent structure 32, and second liquid barrier zone 74 is on an other side ofabsorbent structure 32, wherein each liquid barrier zone 72, 74 is respectively defined by
25 liquid impermeable backsheet 30. More specifically, each liquid barrier zone 72, 74 is
defined, in the width dimension, by a respective side edge 52 of liquid imperrneable inner
12
CA 0224483~ 1998-07-31
W O 97/31602 PCT~US97/01660
layer 48 and a respective topsheet lateral edge 66 in crotch panel 18 (Fig. 2), and by a
side edge 66 and a side edge 37 of an elastic side panel 36 in front and back panels 14,
16 (Fig. 2). Each liquid barrier zone 72, 74 is thus a defined exposed area of liquid
impermeab~e backsheet 30, and extends between backsheet front edge 40 and
backsheet back edge 42 (Fig. 2).
The width of liquid barrier zones 72, 74 is important to the present invention in tha~ each
liquid barrier zone 72, 74 should have sufficient width for the particular absorbent article
design to provide the desired web weave tolerance earlier ~liscussed Each liquid barrier
10 zone 72, 74 has a width of about 2 millimeters or greater, a desired width of about 4
millimeters or greater, and a more desired width of about 6 millimeters or greater. It also
may be desired that a respective width of each liquid barrier zone 72, 74 be relatively
constant behNeen front edge 40 and back edge 42. However, it is within the scope of the
present information to permit the width of liquid barrier zones 72, 74 to vary within the
15 previously described ranges. Finally, and with particular reference to Fig. 3, it is desired
that a portion of construction adhesive 64 be placed or applied along the length in each
liquid barrier zone 72, 74.
It is to be emphasized that there are no specific structures that must define liquid barrier
20 zones 72, 74. For example, it is not a requirement that topsheet 28 should define, with
backsheet 30, the liquid barrier zones 72, 74. It may be that a particular design and
construction of a disposable absorbent article does not require a topsheet 28, and thus
will permit liquid barrier zones 72, 74 to be defined or formed iust by the lateral extension
of a backsheet 30 beyond side edges 62 of an absorbent structure 32. The present2~ invention includes any combination of various positional relationships of structural
elements that define or form the liquid barrier zones 72, 74.
CA 0224483~ 1998-07-31
W O97/31602 PCTrUS97/0166
Continuing primarily with Fig 3, a liquid impermeable containment flap 34 is over first
liquid barrier zone 72, and another liquid impermeable containment flap 34 is over
second liquid barrierzone 74. Furthermore, each liquid impermeable conLail"l)entflap
34 desirably extends the full length and width of its respective liquid barrier zone 72, 74.
Since liquid impermeable containment flaps 34 are subsld"lially the same, a desc, i~Lion
of the left containment flap 34 in Fig. 3 will be made. Liquid impermeable conlai"ment
flap 34, as just described, has a width that desirably exceeds that of liquid barrier zone
72, i.e., has an edge 78 that desirably extends inwardly of, with respect to centerline 38
10 (Fig. 2~, topsheet lateral ed8e 66, and an edge 82 that desirably extends outwardly of
side edge 52. Similariy, liquid impermeable conldil,l,len~ flap 34 desirably extends the
full length of liquid barrier zone 72 between front edçle 40 and back edge 42 ofbacksheet 30.
15 Liguid impermeable containment flap 34 includes an inner portion 76 having an inner
edge 78, and an outer portion 80 having an outer edge 82. Select areas of inner
portions 76 of containment flaps 34 are attached to topsheet 28, adiacent front edge 40
and back edge 42 of backsheet 30. Each liquid impermeable cor,L~ llent flap 34 further
includes a liquid impermeable inner layer 84, and an outer layer 86, which may or may
20 not be liquid impermeable. Generally, outer layer 86 will be a liquid permeable ",ale~ial.
Liquid impermeable inner layer 84 can be vapor permeable or vapor impermeable, and
may be made of the same materials as inner layer 48 of backsheet 30. Similarly, outer
layer 86 can be made of the same ",~leri~ls as outer layer 46 of backsheet 30.
However, if desired, each containment flap 34 can be a single layer of a 5l ~ hle liquid
25 impermeable material. Generally, the choice of materials will be dict~t~d by the
manufacturing process and/or design of the absorbent article. A more detailed
14
CA 0224483~ 1998-07-31
W O 97/31602 PCTrUS97/01660
description of various conlc,i, Iment flap designs and allach~"ents are included in U.S.
Patent No. 5 415 644 issued May 16 1995 the contents of which are incorporated by
reference herein.
5 A flap elastic member 88 is elastically associated with each containment flap 34. In a
specific embodiment flap elastic member 88 is between liquid impermeable inner layer
84 and outer layer 86 at inner portion 76 of a respective C;OI ,l"ent flap 34. The term
"ela~li~lly associated" refers to the ioining of an elastic member to a non-elastic member
such that the two joined members exhibit elasticity. The terms "elastic" and "elasticity"
10 have the conventional meaning in the art which refers to a material or composite elastic
",~Lt:rial that tends to recover its original relaxed size and shape after removal of the
force causing the defor",dLion. Elasticity is expressed in percent. The term "member"
when used in the singular can have the dual meaning of a single element or a plurality of
elements.
Each flap elastic member 88 in a respective con' ~ment flap 34 can be joined or
attached in any suitable manner well known in the art. For example a flap elastic
member 88 can be stretched and then adhered to either one or both inner layer 84 and
outer layer 86. The adhesive used to join or adhere flap elastic member 88 in
20 conl~ ent flap 34 can be applied continuously or intermittently. One suitable method
of applying adhesive is by slot coating. Another suitable method is that described in U.S.
Patent No. 4 711 683 issued December 8 1987 the contents of which are incorporated
by reference herein.
25 Continuing to refer to Fig. 3 a leg elastic member 90 is elastically associated with outer
portion 80 of each liquid impermeable conlai"ment flap 34. Desirably each leg elastic
CA 0224483~ 1998-07-31
W O97/31602 PCTAUS97/01660
member 90 is positioned bet\,veen inner layer 84 and outer layer 86 of a respective
conlai,'",ent flap 34. Each leg elastic member 90 can be adhered orioined in the same
manner as that earlier described for a respective flap elastic member 88.
Continuing the description of a flap elastic member 88, each is desirably positioned
between inner layer 84 and outer layer 86 at inner portion 76, and adjacent a respective
inner edge 78. As illustrated in Fig. 3, there is a folded portion 92 of outer layer 86 that is
folded or wrapped over a flap elastic member 88 and then positioned underneath, as
viewed in Fig. 3, inner layer 84, such that inner layer 84 is sandwiched between folded
portion 92 and outer layer 86. Folded portion 92 is then suitably adhered to inner layer
84 by adhesive bondline 94, which can be any suitable adhesive applied in any known
manner in the art.
Important to the present invention is a means for providing a liquid barrier between liquid
15 impermeable conla;l",lenL flaps 34 and liquid impermeable backsheet 30, in which the
means extends between front edge 40 and back edge 42 of backsheet 30. In one
el,lL)od;.,~ent, such a means is a liquid barrier96 in each ~e:spe~Li~e liquid barrierzone 72,
74, and which extends between front edge 40 and back edge 42. The liquid barrier 96 in
each liquid barrier zone 72, 74 can be any suitable means or mecl lan;~", that provides
20 obstruction to the passage or flow of liquid between a liquid i"l~.e",leable conldi~ ""enL
flap 34 and liquid impermeable backsheet 30. E~-dm, ~es of this feature include, but are
not limited to, an adhesive bondline, a thermal bondline, an ul~ dsonic bondline, or the
like, and including combinations thereof. An adhesive bondline forming or defining a
liquid barrier 96 can be applied in any suitable manner and in any pattern sufficiently to
2~ prevent or obstruct the passage of liquid, such as urine, bet~,veen a co"Ldin",ent flap 34
and backsheet 30 in a respective liquid barrier zone 72, 74. A thermal bondline forming
16
CA 0224483~ 1998-07-31
W O 97/31602 PCT~US97/01660
or defining a liquid barrier 96 can be provided in any suitable manner that appropriately
heats a liquid impermeable co"lai,lment flap 34 and liquid impermeable backsheet 30 to
make them sufficiently tacky so that they can adhere together in a respective liquid
barrier zone 72 74. This assumes the conlai"nlent flap 34 and backsheet 30 are
5 thermally compatible. If not then another layer of material which is thermally co",paliL~le
to both can be positioned between a conlai~ ent flap 34 and backsheet 30 and then all
three therrnally bonded together sufficiently to obstruct the passage of liquid. Similarly
an ulll~sol1ic bondline forrning or defining liquid barrier 96 can also be provided in any
suitable manner and in any suitable pattern sufficiently to obstruct the passage of liquid.
10 Sl ~it~hle IJIL, asonic: appar~lus for providing an ultrasonic bondline are commercially
available from Branson Ull,~sonics Corporation Oanbury Connecticut. If desired a
liquid barrier 96 can include a combination of these or other means for providing
obstruction of liquid flow. For example a liquid barrier 96 couid include an adhesive
bondline in the area of crotch panel 18 (Fig. 2) and a therrnal bond pattern in the areas
~5 of front and back panels 14 16 (Fig. 2).
A desirable feature of the present invention is that each liquid barrier 96 directly joins
liquid impermeable backsheet 30 and a liquid impermeable containment flap 34 In other
words it is desirable that no other layer or substrate be between backsheet 30 and a
20 co~ llaillment flap 34 that would provide a potential defect in or failure of a liquid barrier 96
in obstructing the passage of liquid between backsheet 30 and a conLai. l. "ent flap 34.
For example if topsheet 28 is increased in width so as to extend beyond the outermost
portion of a liquid barrier zone 72 74 a liquid barrier 96 could potentially fail to obstruct
the passage of liquid between backsheet 30 and a conldi"menl flap 34. Thus the
25 desi, y of topsheet 28 being narrower than backsheet sheet 30 such that lateral
edges 66 (Fig 2) are closer to centerline 38 than side edges 44 of backsheet 30. This
CA 0224483~ 1998-07-31
W O97/31602 PCTrUS97/01660
desirability similarly applies to elastic side panels 36 absorbent pad 56 surge layer 58
or any other components of training pant 10.
As thus described a liquid barrier 96 desirably provides a direct mutually contacting
5 joinder between liquid impermeable backsheet 30 and a respective liquid impermeable
co"Lai,)nlent flap 34 to obstruct the passage of iiquid through a barrier zone 72 74.
Pal~l~lhelically and as illustrated in Fig. 3 when backsheet 30 is a multi-layer structure,
and when liquid impermeable conLa;"",ent flaps 34 are multi-layer structures a liquid
barrier 96 directly joins llquid impermeable inner layer 48 of backsheet 30 to liquid
10 impermeable inner layer 84 of a respective cOllLail ""ent flap 34.
Nevertheless the present invention does include embodiments in which a component
can be positioned in a liquid barrier zone 72 74. For example topsheet 28 can have its
lateral edges 66 extend over a respective liquid barrier zones 72 74. In this case it is
15 important that each liquid barrier zone 96 be suitably provided to accommodate the
existence of this additional component such as for exd" ~ topsheet 28 in order to
ensure the obstruction of liquid flow through liquid barrier zones 72 74. If for example
liquid barriers 96 are adhesive bondlines then it is important that the adhesive material
be selectively chosen and appropriately applied by a method and in an amount to create
20 the desired obstruction of liquid flow.
Fach li~uid impermeable conlai",11ent flap 34 is suitably adhered on top of topsheet 28
for example by a respective flap seam 98. Flap seam 98 is desirably an adhesive
bondline joining an intermediate portion of a containment flap 34 to topsheet 28. The
25 height of a con~a;l ""ent flap 34 as measured in a hori~onLal direction in Fig. 3 is then
measured between a fiap seam 98 and an inner edge 78. Each containment flap 34 is
18
CA 0224483~ 1998-07-31
W O97/31~02 PCT~U~97/01660
elastically urged upwardly, relative to topsheet 28, under the elastic tension of a
respective flap elastic member 88. One suitable design and construction of a
containment flap is set forth in U.S. Patent No. 4,704,116 issued November 3, 1987, the
contents of which are incorporated by reference herein. Since one of the objectives of
containment flaps 34 is to impede the flow of urine, or other waste material, and allow
al)so"~lion thereof, each flap seam 98 is desirably positioned over absorbent structure 32
in order to enhance absorption. Thus, any urine or other flowable waste matter that
moves or wicks underneath a flap seam 98 can still be absorbed by that portion of
absorbent structure 32, such as absorbent pad 56, that extends outwardiy beyond a
1~ respective flap seam 98.
The relative position of each flap seam 98 is illlpo,l~"l to the performance of the present
invention. For example, it is desired that each flap seam 98 be disposed or positioned
between a respective flap elastic member 88 and leg elastic member 90. The term
15 "disposed or positioned between" means that flap seam 98 is ,,o,i~u,,lc.lly'' disposed or
positioned, as viewed in Fig. 3. In other words, it is not required that the flap elastic
member 88, flap seam 98, and leg elastic 90 be positioned in a common plane. They
can be vertically displaced relative to each other as is illustrated in Fig. 3. V~ith a flap
seam 98 intermediately positioned between a flap elastic member 88 and a leg elastic
20 member 90, it will not enhance or affect the elasticity of one elastic member 88, 90 at the
expense of the other. For example, if a flap seam 98 is immediately adjacent a flap
elastic member 88, the elasticity of flap elastic member 88 could be diminished due to the
presence of the adhesive associated with a flap seam 98.
25 If, however, the particular design and construction of a ~lrcpos~hle absorbent article
permits, flap seams 98 can be eliminated, and liquid barriers 96 can provide the
19
CA 0224483~ 1998-07-31
WO 97/31602 PCT/US97/01660
additional feature of joining conlai, ~ ent flaps 34 to backsheet 30, or topsheet 28 if it
extends laterally a sufficient dist~nce.
Similarly, each liquid barrier 96 is also desirably disposed or po:,iLioned between a
respective leg elastic member 90 and a respective flap member 88, as illustrated in
Fig. 3.
Continuing to refer to Fig. 3, each liquid impermeable containment flap 34 includes a flap
constrùction adhesive ~100 that adhesively joins flap inner layer 84 to flap outer layer 86
adjacent a respective flap outer edge 82. Flap construction adhesive 100 also serves to
contain the ends of leg elastic members 90 near the front edge 40 and back edge 42 of
backsheet 30, and also prevents undesirable free or loose movement of flap outer layer
86 adjacent outer edge 82 of a flap 34. The purpose of each flap construction adhesive
100 includes joining the layers together for better pe~r~,n"allce, better aesthetics, easier
15 pr~,essi"g during manufacture, and the like.
It is desirable that each flap construction adhesive 100 is outboard of both a respective
leg elastic member 90, liquid barrier 96, and flap elastic member 88.
20 Tuming now to Fig. 4, there is illustrated a fragmentary view of a mo-liricalion, in which
both a respective leg elastic member 90 and flap elastic member 88 are placed inboard
of a respective liquid barrier 96. One reason for this can be due to a particular product
design and construction, for example, where the absorbent structure 32 is shaped
narrower at the crotch, and the leg elastic members 90 are curved to match, or generally
25 parallel, the shape of the absorbent structure.
CA 02244835 1998-07-31
W O 97/31602 PCTAUS97/01660
In Fig. ~, another modiricaliol- is illustrated in which each leg elastic member 90 is also
positioned in a respective liquid barrier zone 72, 74 along with the respective liquid
barrier 56. One reason for this can be to increase or ll~a~ ice the elastlc effects of leg
elastic members 90, since there is less ",alerial, i.e., layers of material, that the leg
elastic members 90 must gather.
While this invention has been described as having a preferred embodiment, it will be
understood that it is capable of further modiricdlions. This application is therefore
intended to cover any varialion, equivalence, use, or adaptation of the invention following
10 the general principles thereof, and including such departures from the present ~~isrJos~re
as come or may come within known or cu:,l ,",ary practice in the art to which this
inventions pertains and fail within the limits of the appended claims.
,
