Note: Descriptions are shown in the official language in which they were submitted.
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ELASTIC LAMINATE
BACKGROUND
1. Technical Field
The present disclosure generally relates to absorbent articles, and more
particularly to an
absorbent article having an elastic laminate structure, that is smooth, low
cost and easily
manufactured, for improving fit, aesthetics and leakage resistance.
2. Back2round of the Related Art
Absorbent articles such as, for example, disposable diapers, adult incontinent
pads,
sanitary napkins, pantiliners, incontinent garments and the like are generally
worn, in
cooperation with garments and disposed against a body surface by infants or
adult incontinent
individuals. The absorbent article is employed to collect and absorb body
fluid discharge, such
as, for example, blood, menses, urine, aqueous body fluids, mucus, cellular
debris and other
forms of body discharge. For example, the absorbent article may be disposed
between the legs
of an individual adjacent a crotch area. The absorbent article is positioned
with a garment and
drawn into engagement with a body surface of the crotch area to collect body
discharge.
As is known, absorbent articles typically include a fluid permeable coverstock
for
engaging the body surface, a fluid impermeable backsheet and an absorbent core
supported
therebetween. The backsheet serves as a moisture barrier to prevent fluid
leakage to the
garment. The absorbent core usually includes a liquid retention material that
faces the body
surface. The absorbent core can include, for example, loosely formed
cellulosic fibers, such as,
for example, wood pulp, rayon, or cotton for acquiring and storing -body
discharge. The
absorbent core may also include tissue wrapping or wadding, and or super
absorbent polymer.
Some absorbent article designs typically incorporate elastic elements in the
waist,
stomach, and leg areas for improving the fit, aesthetics and leakage
resistance. The waist and
stomach elastic elements increase the flexibility of the absorbent article,
allowing the same
article to accommodate a greater range of body sizes. In addition, they make
the article more
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form-fitting for the wearer. Leg gather elastic elements and standing leg
gathers have also been
employed to help reduce leakage from the article when the absorbent cores
cannot absorb body
exudates fast enough.
Typically, these elastic elements include elastic strands to provide the
absorbent article
with retractive forces and a desired range of extension. Attachment of the
elastic strands to the
absorbent article can, however, create undesirable corrugations in the surface
of the absorbent
article. These disadvantageous corrugations may have a high amplitude and low
frequency such
that protuberances are formed giving the absorbent article a "bumpy" feel.
In an attempt to overcome these disadvantages, elastic films have been
employed. Elastic
films, however, may suffer from various drawbacks such as high cost, lower
retractive forces and
lower range of extension.
It would therefore be desirable to overcome the disadvantages and drawbacks of
the prior
art by providing an absorbent article, including an elastic laminate having an
elastic film and
elastic strands. Such an elastic laminate is configured to provide higher
retractive forces and a
wider range of extension. Desirably the elastic laminate is joined with the
absorbent article to
provide a substantially smooth surface laminate and comfort. It is
contemplated that the elastic
laminate is low cost and facilitates easy and efficient manufacture of the
absorbent article.
SUMMARY
Accordingly, an absorbent article, including an elastic laminate having an
elastic film and
elastic strands is disclosed. The elastic laminate is configured to provide
higher retractive forces
and a wider range of extension, and is joined with the absorbent article to
provide a substantially
smooth surface laminate and comfort. The elastic laminate is low cost and
facilities easy and
efficient manufacture of the absorbent article. Objects and advantages of the
present disclosure
are set forth in part herein and in part will be obvious therefrom, or may be
learned by practice of
the present disclosure that is realized and attained by the instrumentalities
and combinations
pointed out in the appended claims for the devices and methods of the present
disclosure
consisting of its constituent parts, constructions, arrangements,
combinations, steps and
improvements herein shown and described.
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In one particular embodiment, an elasticized panel laminate includes a first
nonwoven
layer and a second nonwoven layer. An elastomeric film is positioned between
the first and
second nonwoven layers. The panel further includes a plurality of elastic
strands positioned
between the first and the second nonwoven layers. The elastic film layer- may
include a plurality
of spaced apart film strips. The elastic strands can be positioned directly on
the film strips, or in
the spaces adjacent the strips.
In an alternative embodiment, the elasticized panel laminate may include a
plurality of
elastic film layers. A first elastic film layer is positioned adjacent the
first nonwoven layer, and a
second elastic film layer is positioned adjacent the second nonwoven layer.
The layer of elastic
strands is positioned between the first and the second elastic film layers.
In another alternative embodiment, the elasticized panel laminate may include
a plurality
of elastic strand layers. A first elastic strand layer is adjacent the first
nonwoven layer. A
second elastic strand layer is positioned adjacent the second nonwoven layer.
The elastic film
layer is positioned between the first and the second elastic strand layers.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and features of the present disclosure are set forth with
particularity in the
appended claims. The present disclosure, as to its organization and manner of
operation,
together with further objectives and advantages may be understood by reference
to the following
description, taken in connection with the accompanying drawings, in which:
FIGURE 1 is a perspective view of an absorbent article in accordance with the
principles
of the present disclosure;
FIGURE 2 is an exploded perspective view of an elastic panel of the absorbent
article
shown in=FIGURE 1;
FIGURE 2A is an exploded perspective view of an alternate embodiment of the
elastic
panel shown in FIGURE 2;
FIGURE 2B is an exploded perspective view of another alternate embodiment of
the
elastic panel shown in FIGURE 2;
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FIGURE 3 is an exploded perspective view of another alternate embodiment of
the
elastic panel shown in FIGURE 2;
FIGURE 3A is a plan view of a portion of an alternate embodiment of the
elastic panel
shown in FIGURE 3; and
FIGURE 3B is a cutaway view of an elastic film or elastic strand of the
elastic panel
shown in FIGURE 3 taken along plane 3B in FIGURE 3A.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
The exemplary embodiments of the absorbent article and methods of use
disclosed are
discussed in ternis of fluid absorbent articles, and more particularly, in
terms of an absorbent
article including an elastic laminate structure that is smooth, low cost and
easily manufactured
for improving fit, aesthetics and leakage resistance. The presently disclosed
absorbent article is
contemplated to be employed with, for example, training pants, adult
incontinent products,
disposable diapers, and other incontinent articles.
In the discussion that follows, the term "body-facing surface" refers to a
portion of a
structure that is oriented towards a body surface, and the "garment-facing
surface" refers to a
portion of the structure that is oriented towards a garment and is typically
opposing the body-
facing surface and may be referred to as such. As used herein, the term "body
surface" refers to
a portion of an individual's body that the absorbent article is disposed with
for collecting and
absorbing fluid discharge from the individual. As used herein, the term
"absorbent article,"
"absorbent garment" or "garment" refers to garments that absorb and contain
body waste, and
more specifically, refers to garments that are placed against or in proximity
to the body of the
wearer to absorb and contain the various body discharges and wastes.
A non-exhaustive list of examples of absorbent articles includes training
pants, diapers,
diaper covers, disposable diapers, feminine hygiene products and adult
incontinence products.
The term absorbent articles includes all variations of absorbent garments,
including disposable
absorbent garments that are intended to be discarded or partially discarded
after a single use and
unitary disposable absorbent garments that have essentially a single
structure. As used herein,
the term "training pants" refers to an absorbent article generally worn by
children about the
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lower torso. The absorbent article may be disposable or partially discarded
after a single use.
The absorbent article can be a unitary structure or include replaceable
inserts or interchangeable
parts.
Absorbent articles and diapers may have a number of different constructions.
In each of
these constructions it is generally the case that an absorbent core is
disposed between a liquid
pervious, body-facing topsheet and a liquid impervious, exterior facing
backsheet. In some
cases, one or both of the topsheet and backsheet may be shaped to form a pant-
like article, such
as a training pant. In other cases, the topsheet, backsheet and absorbent core
may be formed as a
discrete assembly that is placed on a main chassis layer and the chassis layer
is shaped to form~ a
pant-like absorbent article. The absorbent article may be provided to the
consumer in the fully
assembled pant-like shape or may be partially pant-like and require the
consumer to take the
final steps necessary to form the final pant-like shape. Training pants are
typically fully formed
and applied by pulling the absorbent article over a child's legs. For a diaper
application, an open
article is provided and wrapped about a child's waist, such as by manually
fastening one or more
fasteners or fastener tabs.
The following discussion includes a description of the absorbent article in
accordance
with the present disclosure. Reference will now be made in detail to the
exemplary embodiments
of the disclosure, which are illustrated in the accompanying Figures.
Turning now to the Figures, wherein like components are designated by like
reference
numerals throughout the several views. Referring to Figure 1, there is a
perspective view
illustrating one embodiment of an absorbent article in accordance with the
present invention.
The absorbent article 50 as illustrated in Figure 1 is of a pull-on or
training pant type and
comprises a main body 30 which has a waist hole 32 and a pair of leg holes 34.
The main body
30 includes a waist gather 36 disposed along the periphery of the waist hole
32, and a leg gather
38 disposed along the periphery of each of the leg holes 34.
The leg gather 38 is formed by the contracting force of elastic regions 40
incorporated
therein. Other elastic regions 42 are provided for improved fitting of the
main body 30 to a waist
portion of a wearer. The main body 30 comprises a backsheet 44 formed of
liquid impermeable
material, a topsheet 46 formed of liquid permeable material, preferably
hydrophilic material, and
an absorbeint core 48 interposed therebetween. According to the present
disclosure, the elastic
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regions 40, 42, lateral side portions 52, waist portions 54 and body sections
56 each include an
elastic laminate panel 10 as described below. Each portion may include one or
a plurality of
elastic laminate panels 10 according to requirements of a particular
application.
With reference to Figures 2, 2A, 2B and 3, an elastic laminate according to
the present
disclosure is shown. In one illustrative embodiment, as sliown in Figure 2,
the elastic panel 10
includes a first outer surface or layer 12 of nonwoven material, a layer of
elongated elastic film
16, a layer of elastic strands 18, and a second outer layer 14 of nonwoven
material. The layers
12, 14, 16, 18 are joined together to form a substantially unitary structure
or panel 10. It is
contemplated that layer 12 may alternatively be forrned of a film, apertured
filni, tissue, or
woven material.
The panel 10 is formed by positioning a layer of tensioned elastic. strands 18
between the
elongated elastic film 16 and either of the nonwoven layers 12, 14, and
joining the layers 12, 14,
16, 18 together. Then the tension in the elastic strands 18 and film 16 is
released thereby
permitting them to~ contract and draw the outer layers 12, 14 into
corrugations (pleats) of a
desired thickness (amplitude) and frequency. When the corrugations are drawn
apart, the panel
has resilient elastic properties. The elasticized panel 10 may be formed into
the elastic
regions 40, 42 or any portion of the training pant 50 using any suitable
method, such as adhesive
bonding or ultrasonic bonding, as will be appreciated by those of ordinary
skill in the art.
The elastic strands 18 can be of suitable elastic material, such as, for
example, natural
rubber, butyl rubber or other synthetic rubber, urethane, or elastomeric
materials such as
spandex, which is marketed under various names, including LYCRA (DuPont),
GLOSPANTM
(Globe) and SYSTEM 7000TM (Fulflex). The elastic film layer 16 can be, for
example, a
urethane based elastic or stretch film, such as EXTRAFLEX available from
Tredegar Film
Products of Richmond, Va. The elastic film layer 16 may also be formed from
other types of
elastic films, multidirectional elastic aggregate such as elastic webbing,
netting, scrim elastic, or
foam. The present invention is not limited to any particular elastic material
or to any particular
shape, size or number of elastics. The non-woven layers 12, 14 may be a
conventional
spunbond-meltblown-spunbond (SMS) material sold under the trade designation
polypropylene
non-woven by Avgol of Holon, Israel. The SMS material may be of any suitable
weight, for
example, 13.5 grams per square meter (gsm), and any suitable thickness, for
example, 0.6 mil.
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Other suitable nonwovens of similar weights or thicknesses may be carded,
spunbond, or
spunlaced materials manufactured by, for example, Polymer Group, Inc. (PGI) of
Mooresville,
North Carolina, BBA Nonwovens Simpsonville, Inc. of Simpsonville, South
Carolina and
Freudenberg Nonwovens of Durham, North Carolina.
The layers 12, 14, 16, 18 may be bonded using joining methods known in the
art, such as,
for example, pressure bonds, thermal bonds, ultrasonic bonds, adhesives, other
attachment
means, or combinations of different bonding methods. In the illustrative
embodiment of the
elasticized panel 10, as shown in Figure 2, the elastic film layer 16 is
bonded to the first
nonwoven layer 12. The elastic strands 18 are bonded to the elastic film layer
16 and the second
nonwoven layer 14. Alternatively, in configurations of the panel 10 described
below with
reference to Figures 2A, 2B, 3 and 3A, the elastic film layer 16 may be
attached to either of the
nonwoven layers 12, 14. The elastic strands 18 may be attached to either the
elastic film layer
16, the nonwovens layers 12, 14, or both.
The film layer 16 can be attached to either of the nonwoven layers 12, 14
using adhesive.
The adhesive can be applied, for example, as a solid coat to either the film
or nonwoven.
Alternately, the adhesive can be applied in either a channeled or uniform
pattern. Suitable
adhesives include HL-1258 by H. B. Fuller Company of St. Paul, Minn., Findley
2031 and
H2587-01 by Ato Findley Inc. of Wauwatosa, Wis., DISPOMELT 34-5665 by
National Starch
Co. of Bridgewater, N.J., DISPOMELTO 34-578A by National Starch Co. of
Bridgewater, N.J.,
and HL 1486UZP, which is available from H. B. Fuller Company of St. Paul,
Minn. Alternately,
the film layer 16 can be joined to the nonwoven 12, 14 using ultrasonic
bonding applied in either
a channeled or uniform pattern.
The strands 18 can be attached to the either the film layer 16, the nonwoven
layers 12, 14
or both using adhesive, ultrasonic, thermal, or pressure bonding, or the like.
Such attachment of
the strands 18 can be performed in either a continuous or intermittent manner.
In this
connection, it is noted that increasing the binding of the tensioned elastic
strands 18 to the
nonwoven or film can cause the strands 18 to become less elastic. Accordingly,
the present
disclosure provides for applying less glue/adhesive on the strands 18 in order
to increase the
elasticity of the formed panel 10. In addition, the strands 18 may be
partially or wholly placed
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within channels (not shown) that have no glue so to form, for example,
grooves, shapes, or
undulations that enhance functionality of the panel 10.
It is envisioned that the elasticized panel 10 may include additional layers
of strands 18,
elastic films 16, nonwovens 12, 14, or other materials arranged in various
configurations suitable
for a variety of different applications. For example, while the elasticized
panel 10 of Figure 2
includes a single layer of strands 18, it is contemplated that the panel 10
can include a plurality
of strand layers 18. In an illustrative embodiment shown in Figure 2A, the
elasticized panel 10
includes first nonwoven layer 12. The panel 10 further includes second
nonwoven layer 14.
Elastic film layer 16 is disposed intermediate the first and second nonwovens
12, 14. A first
layer of elastic strands 18A is disposed between the first nonwoven 12 and the
elastic film 16.
The panel 10 further includes at least a second layer of strands 18B disposed
between the second
nonwoven 14 and the film 16. It is envisioned that each of the strand layers
18A, 18B are
attached (explained in further detail below) to either an adjacent nonwoven or
film or both.
The elasticized panel 10 can include a plurality of elastic film layers 16. In
an illustrative
embodiment shown in Figure 2B, the panel 10 includes first nonwoven layer 12.
Second
nonwoven layer 14 is provided. The panel 10 further includes elastic strand
layer 18
intermediate the first and second nonwovens 12, 14. A first elastic film, such
as, for example, a
first layer of film 16A is disposed between the strand layer 18 and the first
nonwoven layer 12.
The panel 10 further includes a second elastic film, such as, for example, a
second film layer 18B
disposed between the strand layer 18 and the second nonwoven 14.
In an alternate embodiment of the elasticized panel 10, the elastic film layer
can comprise
a plurality of strips. In one example, as shown in Figure 3, the film layer 16
includes a first film
strip 28 and a second film strip 29 spaced apart from the first strip 28. This
configuration
minimizes costs since less film is used. In addition, one or more elastic
strands can be disposed
with the layer gf film strips to form a panel 10 having desired performance
criteria. For
example, the strands can be positioned directly on the film strips, or in the
spaces adjacent the
strips. In an illustrative embodiment, as shown in Figure 3A, the elastic
layer 16 includes a first
set of elastic strands 22 positioned on the first film strip 28. The layer 16
further includes a
second strand set 24 disposed in the space between the first and second film
strips 28, 29. A
third strand set 26 is positioned in the space to the left of the first strip
28. It is envisioned that
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the strands and film can be arranged in other various configurations to form a
panel 10 having
desired operating characteristics.
The elastic strands and elastic films, described above, can be differentiated
using an
identifying aspect ratio corresponding to a particular film or web versus a
particular strand, fiber,
filament, rope or yam. In an alternate embodiment, the aspect ratio is
determined based on the
ratio of the longer dimension to the shorter dimension. For example, as shown
in Figure 3B, the
dimensional parameters of the strand and film components can be defined using
the cross
sectional dimensions of the particular component as represented by the
geometry shown, as taken
along plane 3B on Figure 3A. The greater thickness x represents the width, of
a strand or film,
and is the numerator of the aspect ratio. The lesser thickness represents.the
height y of a strand
or film, and is the denominator of the aspect ratio. It is contemplated that
an aspect ratio of <
(less than) 3:1 defines a strand, and an aspect ratio of ?(greater than or
equal to) 3:1 defines a
film. Other aspect ratios for strands and films are also envisioned. As
indicated in the following
table, elastic strands have aspect ratios of < 3.
Elastic Largest Smallest Aspect Ratio
Manufacturer - Elastic size Dimension Dimensions (mm) (mm) (Largest /
Smallest)
Invista - Lycra 220 dtex 0.3 0.2 1_5
Invista - Lycra 620 dtex 0.4 0.3 1.3
Invista - Lycra 680 dtex 0.5 0.4 1.3
lnvista - Lycra 940 dtex 0.5 0.4 1.3
Invista - Lycra 1100 dtex 0.6 0.4 1.5
Invista - Lycra 1520 dtex 0.6 0.4 1.5
Hyosung - Creora 180 den 0.3 0.3 1.0
Hyosung - Creora 210 den 0.2 0.2 1.0
Hyosung - Creora 300 den 0.3 0.3 1.0
As described above, an economical elastic film layer 16 is combined with a
number of
elastic strands 18 to form an elasticized panel 10 having smooth outer
surfaces 12, 14 (i.e., low
amplitude, high frequency corrugations), and also having desired retractive
forces and range of
extension. The film-to-nonwoven bonding across the wide surfaces of the
elastic film 16
provides the resulting smoothness of the elasticized panel 10. The elastic
strands 18 supplement
the retractive forces of the elastic film 16, and provide the higher
retractive forces and wider
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range of extension of the elasticized panel 10. The elasticized panel 10*is
low-cost and easy to
manufacture.
In an alternate embodiment, various components of elasticized panel 10 may
elongated
relative to other components upon assembly of panel 10. The percentage of
elongation of a
particular component is defined as the degree of difference of an elongated
length of an
elastomeric component versus a relaxed, non-elongated length of the same
component. This can
be expressed by the equation: % Elongation = (elongated length - relaxed
length)/ (relaxed
length) x 100. Thus, a component such as elastic strands 18 may have a
percentage of elongation
that is not equal to the percentage of elongation of elastic film 16. For
example, elastic strands
18 can have a percentage of elongation that is greater than a percentage of
elongation of elastic
film 16 when the components of panel 10 are laminated together. It is
contemplated that elastic
strands 18 may have a percentage of elongation that is less than a percentage
of elongation
elastic film 16, or alternatively, the percentages of elongation for the
components of elasticized
panel 10 may be equivalent.
In an alternate embodiment, elastic film layer(s) 16 and elastic strands 18
include
altemative visual indicia to indicate alternate attachment positions of
closure mechanisms for
adjusting the fit of the article to a desired degree. It is contemplated that
the visual indicia may
include altemative coloring, designs, etc. For example, elastic film layer 16
may be colored blue
and elastic strands 18 may be colored pink. It is envisioned that layer 16 and
strands 18 may
have various combinations of visually contrasting colors. It is further
envisioned that layer 16
and strands 18 may be colored across a range of shading.
The claims are intended to cover all of the foregoing classes of absorbent
articles, without
limitation, whether disposable, unitary or otherwise. These classifications
are used
interchangeably throughout the specification, but are not intended to limit
the claimed invention.
The invention will be understood to encompass, without limitation, all classes
of absorbent
articles, including those described above.
The invention of the present disclosure may be embodied in other specific
forms without
departing from the spirit or essential characteristics thereof. The present
embodiments are
therefore to be considered in all respects as illustrative and not
restrictive, the scope of the
invention being indicated by the appended claims rather than by the foregoing
description, and
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all changes which come within the meaning and range of equivalency of the
claims are therefore
intended to be embraced therein.
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