Note: Descriptions are shown in the official language in which they were submitted.
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DISPOSABLE ABSORBENT ARTICLES WITH IMPROVED
LIQUID ABSORPTION AND RETENTION
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
The present invention relates to disposable absorbent articles and, more
particularly, to a disposable absorbent garment, such as a diaper, a training
pant, an
incontinence pant, or a di$posable feminine hygiene product, having an
improved
unitary cuff.
DESCRIPTION OF THE RELATED ART
Disposable absorbent articles are increasingly popular products in today's
world. Disposable diapers and training pants usage far exceeds that of cloth
diapers;
disposable feminine hygiene products offer improved comfort and utility to the
wearer; and disposable incontinence products offer adults control and
absorption of
the involuntary bowel and bladder discharge associated with many medical
conditions,
especially those conditions associated with advancing years.
One of the biggest problems associated with the above-described disposable
articles is leakage and, consequently, many designs have been developed in an
effort
to comfortably minimize the leakage problem. Some prior art disposable diapers
such
as U.S. Patent No. 4,704,116 to Enloe and U.S. Patent No. 4,695,278 to Lawson,
have standing inner barrier cuffs, combined with elastic leg gathers. The
barner cuffs
and elastic leg gathers work together to retain waste.
The foregoing prior art barrier cuff/elastic gather combinations are effective
to varying degrees in containing discharge from a wearer's body. However, the
designs are generally complex and require multiple steps in fabrication,
resulting in
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undesirable expense and inefficiency. For example, cuff/elastic gather
combinations
require the creation of both a cuff and an elastic gather, which must be
applied and
engineered to work together. Hence, there is a need for a disposable garment
that is
constructed to prevent leakage, which can be efficiently produced.
United States Patent No. 5,643,243 (the "'243 Patent") describes a design that
addresses the foregoing problems. The patent discloses a disposable garment
that
includes a topsheet, a backsheet, an absorptive core disposed between the
topsheet
and backsheet, and an elasticized unitary cuff. The unitary cuff has an edge
proximal
and attached to or extending from the body of the disposable garment and an
edge
distal from the body of the disposable garment. The distal edge is positioned
to
contact the crotch area of a wearer of the disposable garment. The unitary
cuff
exhibits longitudinal elastication along a width between the distal and
proximal
edges. The elastication may assume a variety of structures. For example, it
can
include multiple strands of elastic material or a single width of elastic
material. The
width of elastication may be substantially the distance between the distal
edge and
the proximal edge. While successful, it has been discovered that the unitary
cuff of
the '243 Patent may be improved to provide a more secure construction and
improved
wearer comfort.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide an absorbent
disposable article having an improved unitary cuff.
Another obj ect of the present invention is to provide an improved unitary
cuff
wherein the elastic forces may be varied in order to provide a secure fit
while
maintaining the wearer's comfort.
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According to another object of the invention, there is provided an improved
unitary cuff in which the placement of the proximal elastication is in close
proximity
to the body of the article.
Another object of the present invention is to provide an improved unitary cuff
that provides improved leakage resistance. Particularly, the cuffs should
create a seal
against the wearer's body so that liquid and solid waste does not leak from
the regions
between the cuffs and the wearer's body.
Yet another object of the present invention is to provide an improved unitary
cuff wherein the spacing between the elastication in the cuff varies to
provide
improved fit and comfort.
Therefore, in accordance with one aspect of the present invention, there is
provided a disposable absorbent article with ( 1 ) a body that includes a
topsheet, a
backsheet, and an absorptive core located between and attached to the topsheet
or
backsheet, and (2) an elasticized unitary cuff:'. The unitary cuff has an edge
proximal
to the body and an edge distal from the body. The unitary cuff exhibits
longitudinal
elastication at least along the crotch region of the cuff, wherein the
elastication varies
along the width of the cuff. The distance between the proximal edge and the
distal
edge will be referred to as the width of the cuff Preferably, the elasticized
unitary
cuff exhibits greater elastication force near the proximal edge. In a further
preferred
embodiment, the elastication is provided to the unitary cuffby positioning a
plurality
of strands of elastic material along the width of the cuff The strands closer
to the
proximal edge of the cuff are subjected to greater tension than the strands
closer to
the distal edge.
In accordance with another aspect of the present invention, there is provided
a disposable absorbent article having ( 1 ) a body that includes a topsheet, a
backsheet,
and an absorptive core located between the topsheet or backsheet, and (2) a
cuff
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having a first edge proximal to the body and a second edge distal from the
body. The
cufi,exhibits elastication forces, at least in its proximal and distal
regions. Preferably,
the proximal elastication is greater than the distal elastication.
In accordance with yet another aspect of the present invention, there is
provided a disposable absorbent article having (1) a body that includes a
topsheet, a
backsheet, and an absorptive core located between the topsheet or backsheet,
and (2)
a cuffhaving a first edge proximal to the body and a second edge distal from
the body.
The cuff exhibits elastication at least in its proximal and distal regions and
the
proximal elastication is in close proximity to the article body.
In accordance with still yet another aspect of the present invention, there is
provided a disposable absorbent article having ( 1 ) a body that includes a
topsheet, a
backsheet, and an absorptive core located between the topsheet or backsheet,
and (2)
1 S a cuffhaving a first edge proximal to the body and a second edge distal
from the body.
The elastication comprises a plurality of elastic strands positioned such that
the
distance between the strands in the proximal region ofthe cuffis less than the
distance
between the strands in the distal region of the cuff
Advantageously, the present invention provides a barrier cuff that is
constructed in a way that provides all elasticating material formerly provided
in the
two separate structures of the leg gasketing cuffand the upstanding barner
cumin the
current, improved elasticized unitary cuff. The improved cuff provides a
contractile
force strong enough to provide a seal around the wearer's leg, buttocks or
both. In
addition, the area from which the force is generated may be varied either in
strength
or position to provide a form fit of the diaper.
Other and further objects, features, and advantages of the present invention
will be apparent from the following description of presently preferred
embodiments
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of the invention, given for the purpose of disclosure, and taken in
conjunction with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 shows a top view of a conventional disposable article.
Fig. 2 shows a perspective view of a conventional disposable article.
Fig. 3 shows an exploded view of the disposable article of Fig. 2.
Fig. 4 shows a cross-sectional view of the disposable article taken along line
4-4 of Fig. 2.
Fig. 5 shows a cross-sectional view of a disposable article according
to the present invention.
Fig. 6 shows a cross-sectional view of a disposable article according
to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention can be implemented in any disposable article, such as a
disposable diaper, a training pant, an incontinence product or a feminine
hygiene
product. For purposes of description, the following discussion will be
directed to a
disposable diaper. It is understood, however, that the discussion is equally
applicable
to any other disposable article.
A disposable absorbent diaper should provide a variety of features. A
principal
feature is that it should possess a means for effecting a seal about the
wearer. The
seal advantageously goes around the waist and the legs so that the article
fits snugly,
but more importantly, so that liquid and solid waste does not leak past the
seal. The
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seal may be implemented with the aid of elastic members. The article generally
also
possesses a means for securing the article to the wearer that is easy to
engage/disengage. Also the article generally includes an element that absorbs
the
liquid. Finally, the shape of the article, i.e., the profile, should enhance
the overall
goal of absorbing liquid and retaining it within the article by channeling the
liquid to
inhibit local saturation of the core, and by facilitating the seal around the
wearer.
These features, either individually or in combination, are designed to
accomplish one
or more ofthree purposes: (1) absorbing liquid; (2) preventing liquid and
solid waste
from escaping the article, either through the article material, or through the
gaps
between the article edges and the wearer; and/or (3) dispersing the liquid
about the
article and delivering it to the core material.
Figs. 1 and 2 illustrate some basic features of a disposable diaper 10.
Referring first to Fig. 1, the diaper will be described in relation to its
longitudinally
extending central axis A and its laterally extending central axis B. The
diaper includes
three main regions aligned along the longitudinal axis A. These regions are
the front
waist region 12, the back waist region 14, and the crotch region 16. In the
lateral
direction, the diaper includes ear regions 18 and body portion 20. More
particularly,
the diaper 10 has two ears 22 located along the front waist region 12, and two
ears
24 along the back waist region 14. As illustrated in the drawings, the
resulting diaper
has an hourglass shape, with the crotch region 16 fitting about the crotch of
the
wearer; the front and back waist regions, 12 and 14, respectively, fitting
about the
corresponding waist areas of the wearer; and the ear regions 18 wrapping about
the
wearer to form the completed waist of the diaper. A fastening structure 2b,
for
example, a tape fastener, is affixed to each of the ears 24 along the back
waist region
14 of the diaper 10. The fasteners 26 adhere to a fastening surface on the
corresponding ear 22 to secure the diaper to the wearer. Particularly, after
the diaper
is positioned on the wearer, the ears 24 along the back waist region 14 are
brought
around the wearer's waist and toward the wearer's front and into alignment
with the
ears 22 along the front waist region 12. The fasteners 26 are then secured to
the front
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ears. The corresponding securing surface on the front waist region 12 may be
located
on the interior or exterior surface of the diaper 10. Furthermore, the
fasteners 26 can
be located on the ears 22 of the front waist region 12 and attached to the
ears of the
back waist region 14; however, this latter construction is currently not
preferred since
it is more inconvenient to change a diaper having this construction. It is
understood
that fastening means, other than tape, may be used; for example, a hook and
loop
structure in which a tab having hook structures is attached to the back waist
ears and,
when placed on the wearer, is secured to loop members along the front waist
region.
The diaper 10 additionally may have two transverse elastic waist members 28
and 30 located at each end of the diaper, roughly between the respective ears.
When
the diaper 10 is properly placed on the wearer, the elastic waist members 28
and 30
form the "top" of the article-i. e., the uppermost part. The elastic waist
members 28
and 30 have essentially two functions. The first of these functions is to
secure the
diaper 10 snugly around the waist of the wearer so that it does not slip
during
wear-i.e, it forms an elastic waistband once the diaper 10 is placed on the
wearer.
The second function, related to the first, is to form a seal around the
wearer's waist
so that waste produced by the wearer does not leak out of the top of the
diaper 10.
Figs. 1 and 2 also show longitudinally stretchable elastic gasketing cuffs 32
positioned along the two longitudinal edges of the diaper 10. When the diaper
10 is
properly affixed to the wearer, each gasketing cuff32 encircles a leg of the
wearer and
thereby provides a seal to prevent leakage laterally from the interior of the
diaper.
The elastics of the leg gasketing cuffs 32 are generally applied in the
stretched or
extended condition. In a common application, the elastics are placed between
the
topsheet and backsheet in the stretched condition and glued or otherwise
attached to
one or both of the sheets. The elastics are then released to allow them to
retract and
form gathered leg regions depicted in Fig. 2 at 36.
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The figures, and particularly Fig. 3, also illustrate the presence of
longitudinally extending upstanding barrier cuffs 34. The barrier cuffs 34
extend
upwardly from the topsheet 50, i.e., toward the wearer, and are positioned
laterally
in both directions from the longitudinally extending central axis A (see Fig.
1). The
barrier cuffs 34 extend longitudinally along the diaper 10 at least in the
crotch region
16. The barner cuffs 34 include elastic members 38 that act to contract the
barner
cuffs 34 about the buttocks of the wearer. The barrier cuffs 34 may be
positioned at
a variety of distances from the longitudinal centerline A of the diaper 10.
For
example, the barrier cuffs 34 may be inboard or outboard of the gasketing
cuffs 32.
I 0 The barrier cuffs 34 may comprise separate pieces that are secured, e.g.,
by gluing, to
the topsheet 50. In addition, the barrier cuffs 34 may be formed from the
topsheet SO
or backsheet 40.
Fig. 4 shows a cross-sectional view of the diaper 10 taken along line 4-4 of
I 5 Fig. 2. Fig. 4 illustrates the various layers of the diaper. Referring to
Fig. 4, as well
as Fig. 3, and beginning with the layer positioned farthest from the wearer,
the diaper
is comprised of a backsheet 40, barrier layer 42, a bottom tissue layer 44, an
absorbent core 46, another tissue layer 48, and a topsheet 50. Many
conventional
diapers may include more or less layers, though the state-of the-art diapers
generally
consist of at least a backsheet, a topsheet and some type of absorbent core
between
these two layers.
Adjoined to either transverse end of the barrier layer 42 are two foam stretch
waist bands 52 that form, in concert with at least the topsheet 50 and
backsheet 40,
the elastic waist members 28 and 30. As previously mentioned, the elastic
waist
members 28 and 30 partially encircle the waist of the wearer. Two tape
fasteners 26
are also afFxed to the backsheet 40.
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Against this general background, the previously mentioned '243 Patent
describes an advancement to the traditional diapers described above and
illustrated in
Figs. l-4. The '243 Patent describes a unique structure in which the gasketing
leg cuff
elastication and the barner cuff elastication are combined into a unitary
upstanding
barrier cuff. The resulting invention provides advantageous sealing against
leakage,
while avoiding the increased cost and processing difficulties of providing a
separate
barner cuff and gasketing leg cuff elastication.
While the '243 Patent has proved successful, it has been discovered that the
design may be improved by adjusting the positioning, tensioning or both of the
elastication of the unitary barrier cuff. Particularly, it has been discovered
that the
elastication nearer the proximal edge (referred to also as the proximal
elastic or the
elastic in the proximal region of the cuff) should exhibit greater tensioning
than the
elastication nearer the distal edge (referred to also as the distal elastic or
the elastic in
the distal region of the cuff). This difference in elastication can be
achieved by a
variety of ways, including utilizing proximal elastic which has a higher
contractile
force than the distal elastic or positioning the proximal elastics closer
together than
the distal elastics. Varying the tensioning provides a unitary cuff which has
a firm
elastication force at the proximal edge that helps to position the cuff away
from the
main body of the article and curls the body of the garment around the wearer,
while
lower elastication forces located at the distal edge provide greater
flexibility to the
unitary cuff and comfort to the wearer where the garment contacts the skin. In
a
preferred embodiment, a diaper according to the present invention includes
elastic, for
example, multiple elastic strands or a single width of elastic, in which the
contractile
force of the elastication closest to the proximal edge is about 10 to 50
percent greater
than that at the distal edge. Most preferably, the contractile force of the
proximal
elastic is about 25% of the distal contractile force.
In an alternative embodiment, the elastication ofthe cuffcomprises a series of
elastics in which the proximal elastics are more closely spaced together than
are the
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distal elastics. Preferably, the distance between the proximal elastics is
equal to or less
than about 50% of the distance between the distal elastics. Of course, both
approaches
of increasing proximal tensioning may be utilized in a diaper.
Furthermore, it is preferred that the proximal elastication be positioned in
close
proximity to the proximal edge of the cuff. Preferably, the most proximal
elastication in
the cuff is positioned at a distance from the body that is less than or equal
to about 15%
of the total cuff width. For example, in one embodiment in which the cuff is
approximately 25 mm wide, the elastic closest to the body is positioned about
3 mm from
the body. Likewise, the most distal elastication in the cuff should be
positioned close to
the distal cuff edge, preferably, also less than or equal to about 15% of the
total cuff
width and, most preferably, less than or equal to about 10% of the total cuff
width. For
example, for a cuff or about 25 mm, it is preferred that the elastication be
within 3mm
of the distal edge and, most preferably, within 2mm or less of the distal edge
of the
unitary cuff.
The unitary cuffs may be positioned laterally at various positions from the
centerline of the diaper to the lateral edges of the envelope. Preferably, the
cuffs are
positioned outboard of the absorbent core and, most preferably, are positioned
near the
longitudinal edges of the diaper so that the distance between the cuffs is at
least 85% of
the width of the total article with in the crotch region. .In a example, the
unitary cuffs are
centered on the disposable garment crotch region and positioned 85mm from the
longitudinal center (A) of the diaper (i.e., 170mm between the cuffs). A
preferred total
width of the disposable garment at the crotch region is 200mm.
In one preferred embodiment and referring to Figs. 5 and 6, a unitary cuff 158
is constructed using five strands of elastic material (A, B), which are spaced
from one another
generally along the width of the cuff 158 between a distal edge 154 and a
proximal edge 152
adjacent body 156 of the article (Fig. 5). The strands (B) are two strands of
940 decitex
LYCRA XA elastic threads made by the DuPont Company with a higher contractile
force than
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strands (A). Strands (A) may be three strands of 740 decitex LYCRA XA elastic
threads, a
lower contractile force than the 940 deciter LYCRA XA elastic threads. The
strands are
generally evenly spaced along the width of the unitary cuff 158.
S , Fig. 6 shows another preferred embodiment wherein the elastic region of
the unitary
cuff 158 has elastic bands with the same elastication force and the spacing
between the elastic
strands is varied. As Fig. 6 illustrates, the proximal elastics B are
positioned closer together
than are the distal elastics A. In one embodiment, the distance between the
proximal elastics
is equal to or less than one-half the distance between the distal elastics. In
yet another design
(not shown), the unitary cuff may have proximal elastics that have contractile
forces that are
greater than the distal elastics and that are spaced closer together than the
distal elastics.
The unitary cuff may be easily formed and manufactured utilizing know
methodologies and equipment, including the technique taught by U.S. Patent No.
5,536,350.
The unitary cuffs may be formed integrally from the topsheet or backsheet
material, or may
be formed of separate materials, which may or may not be used to form the
remainder of the
distal flaps of the article. The unitary cuffs may extend along the length of
the article, or only
may extend along the crotch zone of the article.
The remaining discussion describes, in more detail the various layers and
structures
that comprise the diaper of Figs. 1-4.
Backsheet
The backsheet material can be selected from a number of different materials
such as polyethylene,
polypropylene, polyolefin film, or other materials. Preferably, the backsheet
material allows air to
circulate through. This attribute is generally referred to as "breathable," or
"vapor" permeable, to
distinguish it from liquid permeable. The backsheet can also be made of a
liquid permeable,
nonwoven web, laminated to a film barrier layer underneath. The barrier layer
may or may not be
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vapor permeable, and it may be a "mask" that is less than the overall width of
the
other backsheet materials. A preferred backsheet material is an outer layer of
spunbond polypropylene fiber with a basis weight of about 1 S gsm, available
from
BBA Nonwovens, Simpsonville, SC. Adhesively laminated to the spunbond is,
preferably, a polyethylene film of about 0.5 mil (0.012mm) thickness that is
available
from Exxon Chemical USA, Houston, TX, using adhesive available from National
Starch and Chemical Company, Bridgewater, NJ. Other examples of backsheet
material include SM or SMS (spunbond/meltblown/spunbond) nonwoven webs, and
breathable or nonbreathable films of 0.5 mil to 2.0 mils in thickness.
Topsheet
Topsheets may be constructed of a wide range of materials including
nonwoven webs of natural (such as wood or cotton) or synthetic fibers (such as
polypropylene or polyester), or some combination, or apertured film. A
preferred
topsheet material is 15 gsm spunbond polypropylene from Avgol Nonwoven Fabrics
ofHolon, Israel. The topsheet may be impregnated with surfactant to facilitate
liquid
transfer. The surfactant may be targeted, such as in the center zone of the
disposable
article, above the core material. The inner surface of the topsheet may be
impregnated
with a chemical to increase surface tension of the liquid. The topsheet may be
formed
of multiple materials which vary across the width of the topsheet, thus
allowing the
creation of preferred properties in different zones of the topsheet. For
instance, a
topsheet may be constructed of a three piece material which may be used to
form cuffs
from a hydrophobic end material and a center zone of hydrophilic material.
Core
The core is formed of highly absorbent material for absorbing fluid received
through the topsheet. The core has an inner surface, in fluid communication
with the
topsheet, an outer surface, and two lateral side surfaces. In this
application, the term
"core" (shown as the superabsorbent and fluff pulp core layer 46 in Fig. 3)
shall be
used to refer generally to that layer between the topsheet 50 and the
backsheet 40,
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placed directly between a top tissue layer 48 and a bottom tissue layer 44,
and to
which the absorbent property of the article is generally attributable. The two
tissue
layers 48 and 44 encapsulate the core and may be joined to form a pocket,
e.g., by
heat fusion, sonic bonding, or adhesives. The core material generally
comprises a
rectangular region of the diaper 10 viewed from the perspective as in Fig. 2,
which,
when the article 10 is placed on the wearer, is juxtaposed between the
wearer's legs,
against the crotch area in the area most likely to receive waste.
The most desirable characteristics of the core material are that it absorb
large
quantities of liquid, that it absorb quickly, and that it b~; as thin as
possible. Attempts
to satisfy these constraints have led to numerous core compositions. In
addition, the
structural configuration of the core is also manipulated to enhance
absorbency, e.g.,
channels or grooves can be created to optimally disperse the liquid waste.
Many core compositions in the prior art are comprised of two components:
a fluffed wood pulp component, for wicking and structural integrity, and a
high-
absorbency (or superabsorbent) material, for containing liquids. As expected,
the
majority of the volume of the article (i.e., its "bulkiness") is due to the
fluff
component. The fluffed wood pulp layer may be a composite material; e.g., an
airlaid
sheet bound by adhesive or containing thermally bondable fibers that are
melted to add
additional integrity to the structure. The high-absorbency material can be
comprised
of numerous compounds. A selection of suitable materials includes inorganic
materials, such as polyvinyl alcohol, polyacrylates, various grafted starches,
and cross-
linked polysodium acrylate. Further; the high-absorbency materials can be
manufactured and utilized in the diaper, etc., in numerous forms such as
particles,
fibers, foams, and layers.
The two-component system is necessary because many of the superabsorbent
materials are unable to absorb liquid at, or even near, the rate at which it
is applied by
the article. Therefore, an additional material, the wood pulp core or
composite, holds
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the liquid and delivers it to the superabsorbent material, to absorb at a rate
slower than
the initial assault from the wearer, and to allow the superabsorbent material
to fully
absorb the liquid. In addition, the fibers prevent "gel-blocking" which may
occur as
the superabsorbent particles swell upon absorption of liquid and block the
interstitial
spaces between particles, thus cutting offchannels for the liquid to flow and
encounter
with unsaturated particles. The fibers prevent gel-blocking by dispersing the
particles,
thus minimizing the potential for particle-to-particle contact. Several
patents in the
prior art are specifically directed to composites which curtail gel-blocking,
such as
U. S. Patent No. 5,147,343. Hence, achieving optimal absorbency (measured both
as
la capacity and rate) involves not only identifying the suitable material
which comprise
the two components, but identifying the optimal ratio of the two components.
Acquisition La ~~er
The article may contain an additional layer between the top tissue layer 48
and
15 the topsheet 50. This additional layer is called an acquisition layer or
surge layer. The
acquisition layer acts to spread out the liquid flow so that the liquid is
distributed more
evenly over the core surface. This feature serves to slow down the flow so
that the
liquid has time to be absorbed by the core. The layer also serves to prevent
the core
from being saturated in a localized region, while the remainder of the core is
not
20 absorbing any liquid.
Securing Elements
The article must be secured to the wearer. This is most important with respect
to diapers since they are not pulled upon the wearer, like training pants, or
incontinent
25 briefs, but are fastened around the wearer. The securing elements
compliment the
elastic members by effecting a seal between the wearer and the waist band and
leg
cuffs, so that liquid is contained within the article and then absorbed; in
other words,
so that the liquid does not leak through gaps between the wearer's legs and
the edge
of the article. The securing elements may be adhesive, hook and loop belts,
or,
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conceivably, straps or strings-i.e., anything that will secure one end of the
article to
the longitudinally opposite end.
According to Figs. l, 3 and 4 above, the diaper 10 is affixed to the wearer by
tape fasteners 26 adhesively affixed to the backsheet 40. The tape fasteners
26 are
contacted with the transversely opposite ear 22 extending from the backsheet
40,
where they remain affixed due to an adhesive compound applied to the fasteners
26.
A target area may be provided to cooperate with the fastener elements to
secure the
back of the diaper to the front. The target area will have characteristics
appropriate
to the type of fastener used. For example, if the fastener is a hook type
fastener, the
target will have appropriate loop characteristics. If the fastener is an
adhesive, the
target will have a surface to which the adhesive will adhere.
Waist Elastics
Waist elastics 28 and 30 (see Fig. 1) are elastic members that may be
positioned along the transverse portion of the article so that when worn, they
are
located along the waist of the wearer. Generally speaking, the waist elastics
of the
article preferably satisfy two criteria. First, they must create a seal
against the waist
so that liquid waste does not leak from the regions between the waist elastics
and
waist of the wearer. This seal is significant because, although the liquid may
eventually be absorbed by the core material, the assault of liquid by the
wearer may
overwhelm the absorption rate capacity of the core material, hence the waist
elastics
must contain the liquid while it is being absorbed. The waist elastic may be
constructed as an integral part of the diaper as shown. It may also be
attached to, or
in place of, the outboard ear of the diaper, as a separate feature.
CA 02338053 2001-O1-17
WO 00/03670 PCT/US99/15700
Shane
Manipulating the shape of the article can accomplish several things. First, a
more precise contour around the wearer's crotch area can prevent the article
from
bunching up, creating pools of liquid which will, in turn, locally saturate
the
underlying core material. Second, the shape can be manipulated to control the
seal,
or the closure of gaps between the edges of the article and the wearer. Hence,
a
narrower profile may be preferable to achieve a smooth liquid contact zone
against the
wearer's crotch (i.e., no bunching); however, a narrower profile means less
surface
area available for core material, hence less total absorption. Similarly, a
larger profile,
while more costly, can more readily accommodate a variety of sized wearers,
whereas
a narrower profile is unsatisfactory for larger-than-normal wearers.
The present invention, therefore, is well-adapted to carry out the objects and
attain the ends and advantages mentioned, as well as others inherent therein.
While
presently, preferred embodiments of the invention have been given for the
purpose of
disclosure, numerous changes in the details of construction, arrangement of
parts, and
steps of the process may be made. These changes will readily suggest
themselves to
those skilled in the art and are encompassed within the spirit of the
invention and the
scope of the appended claims.
16
