U.S. patent application number 10/095425 was filed with the patent office on 2002-10-24 for disposable absorbent article.
This patent application is currently assigned to Kimberly-Clark Worldwide, Inc.. Invention is credited to Damico, Joyce Ann, Gross, Jacqueline Ann, Lingnowski, Veronica Maria, Mitchler, Patricia Ann, Rajala, Gregory John, Rasmussen, Shelley Rae, Sehrading, Mark Scott, Suke, Paul Daniel, Suprise, Jody Dorothy, Van Gompel, Paul Theodore.
Application Number | 20020152540 10/095425 |
Document ID | / |
Family ID | 26810342 |
Filed Date | 2002-10-24 |
United States Patent
Application |
20020152540 |
Kind Code |
A1 |
Van Gompel, Paul Theodore ;
et al. |
October 24, 2002 |
Disposable absorbent article
Abstract
A three dimensional disposable panty for holding a sanitary pad.
The panty may have elasticized leg and waist openings and be
stretchable about the hip and stomach regions of a user. The panty
provides backup leakage protection to the sanitary pad. The panty
includes an absorbent barrier composite positioned in the crotch
area and extending into the body of the disposable panty front and
back and over the leg elastics to trap pad leakage inside the pant
and prevent liquid strike through onto outer clothing and bed
linen.
Inventors: |
Van Gompel, Paul Theodore;
(Hortonville, WI) ; Damico, Joyce Ann; (Neenah,
WI) ; Gross, Jacqueline Ann; (Neenah, WI) ;
Lingnowski, Veronica Maria; (Menasha, WI) ; Mitchler,
Patricia Ann; (Neenah, WI) ; Rajala, Gregory
John; (Neenah, WI) ; Rasmussen, Shelley Rae;
(Oshkosh, WI) ; Sehrading, Mark Scott; (Kaukauna,
WI) ; Suke, Paul Daniel; (Appleton, WI) ;
Suprise, Jody Dorothy; (Neenah, WI) |
Correspondence
Address: |
WILHELM LAW SERVICE, S.C.
100 W LAWRENCE ST
THIRD FLOOR
APPLETON
WI
54911
|
Assignee: |
Kimberly-Clark Worldwide,
Inc.
Neenah
WI
|
Family ID: |
26810342 |
Appl. No.: |
10/095425 |
Filed: |
March 12, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10095425 |
Mar 12, 2002 |
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09770992 |
Jan 26, 2001 |
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6367089 |
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09770992 |
Jan 26, 2001 |
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08745303 |
Nov 12, 1996 |
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6240569 |
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08745303 |
Nov 12, 1996 |
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08263229 |
Jun 21, 1994 |
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08263229 |
Jun 21, 1994 |
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08112783 |
Aug 31, 1993 |
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Current U.S.
Class: |
2/406 |
Current CPC
Class: |
A61F 13/505 20130101;
A61F 13/72 20130101; A61F 13/496 20130101 |
Class at
Publication: |
2/406 |
International
Class: |
A41B 009/04 |
Claims
We claim:
1. A disposable panty adapted to receive a primary absorbent, said
primary absorbent having a liquid permeable inner sheet, a liquid
impermeable outer sheet and an absorbent member disposed
therebetween, said disposable panty comprising: a) an outer cover
having front and back body portions connected by a crotch portion,
said front and back body portions connected together to form a
waist opening and two leg openings; and b) an absorbent barrier
composite associated with said crotch portion, to which said
primary absorbent is fastened and which, in use, holds said primary
absorbent against the body of a user, said absorbent barrier
composite having an impervious layer and an secondary
absorbent.
2. The disposable panty of claim 1 wherein said absorbent barrier
composite is essentially coterminous with the edge of the crotch
portion.
3. The disposable panty of claim 1 wherein said secondary absorbent
is associated with the liquid impermeable outer sheet of said
primary absorbent.
4. The disposable panty of claim 1 wherein said secondary absorbent
comprises a support layer and an absorbent rich layer.
5. The disposable panty of claim 3 wherein said absorbent rich
layer comprises pulp.
6. The disposable panty of claim 1 wherein said absorbent barrier
composite covers a portion of said front and back body
portions.
7. The disposable panty of claim 1 wherein said secondary absorbent
has a total absorbent capacity of less than about one half of the
capacity of said primary absorbent.
8. The disposable panty of claim 6 wherein said secondary absorbent
has a total absorbent capacity of less than about 6 grams.
9. The disposable panty of claim 7 wherein said secondary absorbent
has a total absorbent capacity of from about 3 grams to about 6
grams.
10. The disposable panty of claim 3 wherein said primary absorbent
may be refastenably attached to said absorbent barrier
composite.
11. The disposable panty of claim 1 wherein said primary absorbent
has a total absorbent capacity of at least about 10 grams.
12. The disposable panty of claim 10 wherein said primary absorbent
has a total absorbent capacity of at least about 20 grams.
13. The disposable panty of claim 1 wherein said edge of said leg
opening toward said back portion of said disposable panty is
essentially linear and forms a 60.degree. angle with the
longitudinal centerline of said panty.
14. The disposable panty of claim 12 wherein said leg opening
facing said front portion of said disposable panty is essentially
perpendicular to the longitudinal centerline of said disposable
panty.
15. The disposable panty of claim 13 wherein said outer cover
carries at least one elastic around each of said leg openings which
forms a gather around each of said leg openings.
16. The disposable panty of claim 14 wherein said outer cover
carries at least one elastic around said waist opening which forms
a gather around the waist.
17. The disposable panty of claim 16 wherein said outer cover
carries at least one elastic around said front and back body
portions and forms a gather around the body of said disposable
panty.
18. The disposable panty of claim 17 wherein said body elastic
about said disposable panty extends from said waist opening to said
leg openings.
19. The disposable panty of claim 18 wherein said waist elastic has
a stress which is greater than the stress per unit width in said
body elastic.
20. The disposable panty of claim 19 wherein said leg elastic
comprises multiple individual elastic threads, and said waist
elastic comprises multiple individual elastic threads, said leg and
waist elastic threads being spaced from about 4 mm to about 17 mm
apart.
21. The disposable panty of claim 1 wherein said crotch region is
wider than said primary absorbent.
22. The disposable panty of claim 21 wherein width of said crotch
portion is sized to be about 13 mm wider than the width of said
primary absorbent selected for use by the user.
23. The disposable panty of claim 22 wherein said crotch portion is
at least about 102 mm in width.
24. A disposable panty adapted to receive a primary absorbent, said
primary absorbent having a liquid permeable inner sheet, a liquid
impermeable outer sheet and an absorbent member disposed
therebetween, said panty comprising: a) an outer cover having front
and back body portions connected by a crotch portion, said front
and back body portions connected together to form a waist opening
and two leg openings; and b) an absorbent barrier composite
associated with said crotch portion, to which said primary
absorbent is fastened and which, in use, holds said primary
absorbent against the body of a user, said barrier composite having
an impervious layer and a secondary absorbent, c) said outer cover
includes a leg elastic positioned around each of said leg openings
to form a gather around each said leg opening, a waist elastic
positioned around said waist opening to form a gather around said
waist opening and a body elastic positioned around said front and
back body portions to form a gather of said front and back body
portions.
25. The disposable panty of claim 24 wherein said waist elastic
tension is from about 380 g to about 1000 g.
26. The disposable panty of claim 24 wherein said leg elastic
tension is from about 375 g to about 1000 g.
27. The disposable panty of claim 24 wherein said body elastic
tension is from about 500 g to about 850 g.
28. A disposable panty adapted to receive a primary absorbent, said
primary absorbent having a liquid permeable inner sheet, a liquid
impermeable outer sheet and an absorbent member disposed
therebetween, said disposable panty comprising: a) an outer cover
having front and back body portions connected by a crotch portion,
said front and back body portions connected together to form a
waist opening and two leg openings; b) an absorbent barrier
composite associated with said crotch portion, to which said
primary absorbent is fastened and which, in use, holds said primary
absorbent against the body of a user, said barrier composite having
impervious layer and an secondary absorbent; c) a majority of the
length of the back half of the edge of said leg opening is linear,
said linear portion forming an angle with the longitudinal
centerline A-A of said panty of from about 50.degree. to about
65.degree.; and d) a majority of the length of front half of the
edge of said leg opening is linear, said linear portion forming an
angle with the longitudinal centerline A-A of said panty of from
about 75.degree. to about 110.degree..
29. The disposable panty of claim 28 wherein said edge of said leg
opening toward said back body portion of said disposable panty
essentially forms a 60.degree. angle with the longitudinal
centerline A-A of said panty.
30. The disposable panty of claim 29 wherein said leg opening
facing the front body portion of said disposable panty is
essentially perpendicular to the longitudinal centerline A-A of
said disposable panty.
31. The disposable panty of claim 1 wherein said absorbent barrier
composite has a stiffness of less than about 400 grams.
32. The disposable panty of claim 1 wherein said secondary
absorbent has a stiffness of less than about 250 grams.
Description
FIELD OF THE INVENTION
[0001] This present invention relates to undergarments in general,
and more specifically to women's disposable undergarments having a
fluid repellent region and an absorbent layer to be used with a
woman's normal feminine care protection during her menstrual
period.
BACKGROUND OF THE INVENTION
[0002] Regular undergarments in current use are made of cotton
and/or synthetic materials. The cotton and synthetic panties
typically do not offer barrier protection. Often the synthetic
panties have a cotton lined crotch to absorb vaginal discharges or
perspiration. The absorbent/barrier properties of regular
undergarments are minimal such that any vaginal, discharge and/or
heavy perspiration may strike through onto outer clothing (i.e.,
penetration of liquid from the interior to the exterior of the
panty.)
[0003] Panty liners and feminine care sanitary napkins or pads used
with regular undergarments have polyethylene backings that provide
some barrier properties needed to prevent liquid strike through.
However, if the vaginal discharge extends to the sides or the ends
of the pads it can leak onto the undergarment. This leakage can
stain the undergarment. Depending upon the amount of leakage,
liquid may strike through or go around the undergarment to stain
outer clothing and or bedding. Women with heavy periods often use
one or more maxi pads, double pads and/or tampons alone, or in
combination, and change these pads and tampons frequently to
prevent embarrassing, messy, leakage and/or staining of outer
clothing. In some cases, during their heaviest flow days, women
will restrict their activities and stay home.
[0004] A majority of women experience some leakage of menses from
their pads to their undergarments. This varies from being limited
to a small number of pads leaking onto only the undergarment during
light flow to leakage onto the wearer's outer clothing on almost
half the pads worn during heavy flow. Normally this leakage occurs
at the side of the product, although end leakage is also a problem.
Placement of maxi pads and overnight pads in the crotch of regular
undergarments shows that, at best, the pads lay on the leg elastic
and, at worst, overhang the leg elastics. This causes side leakage
onto the undergarment and possibly onto outer clothing. Typical
leakage from the pads is caused by poor fit of the pad to the body,
improper positioning of the pad by the user and lack of absorbency.
Leakage from the undergarment onto the outer clothing is due to
incompatibility between the pad width and the panty crotch width
and lack of barrier properties, in the panty material around the
edge portion of the pad.
SUMMARY OF THE INVENTION
[0005] Briefly, this invention describes a three dimensional,
disposable, discrete panty with fully elasticized leg and waist
openings that is circumferentially stretchable about the hip and
stomach regions and which provides back-up leakage protection to
feminine care products. It is particularly useful during the
wearer's menstrual period, normally occurring in non-pregnant women
about every four weeks, from menarche to menopause.
[0006] The protection benefit is obtained by providing a flexible
secondary absorbent associated with the crotch of the undergarment
which holds the primary absorbent in proper location for vaginal
discharge (menses). The secondary absorbent extends from the crotch
into the body of the undergarment front and back and may extend
over the leg elastics. This provides an undergarment which is
capable of trapping and absorbing the leakage from the pad and
preventing liquid strike through onto outer clothing and bed
linen.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention will be more fully understood and
further advantages will become apparent when reference is made to
the following detailed description of the invention and the
drawings, in which:
[0008] FIG. 1 is a top plan view of a panty article of the present
invention in a preassembled flat configuration;
[0009] FIG. 2 is a perspective view of a full-sized, disposable
menstrual panty of the present invention.
[0010] FIG. 3 is a sectioned view taken along view lines 3-3 of
FIG. 1 and illustrating the outer cover, liner and elastics.
[0011] FIG. 4 is a sectioned view taken along view lines 4-4 of
FIG. 1 and illustrating the absorbent layer, barrier and outer
cover.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] The following detailed description is made in the context of
an article including a disposable panty for holding a sanitary pad
in place during use. It is readily apparent, however, that the
present invention can be employed with other disposable articles,
such as feminine tampons, incontinent garments and the like.
[0013] The disposable panty of FIG. 1 illustrates the preferred
embodiment of the present invention in a flat configuration prior
to assembly. In FIG. 1, a panty 12 is shown having an outer cover
13 which includes a front body portion 14, a back body portion 15,
a front waist portion 16, a back waist portion 17, a crotch portion
18, waist liner 26 (not shown), leg liner 38 (not shown) and body
liner 80 (not shown).
[0014] The outer cover 13 is compliant and soft feeling to the
wearer. The outer cover 13 may be liquid pervious, permitting
liquids to readily penetrate into its thickness, or impervious,
resistent to the penetration of liquids into its thickness. A
suitable outer cover 13 may be manufactured from a wide range of
materials, such as natural fibers (e.g., wood or cotton fibers),
synthetic fibers (e.g., polyester or polypropylene fibers) or from
a combination of natural and synthetic fibers or reticulated foams
and apertured plastic films.
[0015] There are a number of manufacturing techniques which may be
used to manufacture the outer cover 13. For example, the outer
cover 13 may be woven, nonwoven, such as spunbonded, carded, or the
like. A suitable outer cover 13 is carded, and thermally bonded by
means well known to those skilled in the fabric art. Alternatively,
the outer cover is a spunbond. Ideally, the outer cover is a
spunbond polypropylene nonwoven with a wireweave bond pattern
having a grab tensile of 19 pounds as measured by ASTM D1682 and
D1776, a Taber 40 cycle abrasion rating of 3.0 as measured by ASTM
D1175 and Handle-O-Meter MD value of 6.6 grams and CD value of 4.4
grams using TAPPI method T402. Suitably, the spunbond material is
available from Kimberly-Clark Corporation, located in Roswell, Ga.
The outer cover 13 has a weight from about 0.3 oz. per square yard
(osy) to about 2.0 osy and alternatively about 0.7 osy. Preferably,
the outer cover of the undergarment has a printed pattern, is
colored or is decoratively embossed.
[0016] Referring to FIGS. 1, 2 and 3, an edge 60 of front body
portion 14 is assembled with an edge 62 of the back body portion 15
to form a seal 64. Similarly, an edge 66 of the front body portion
14 is assembled with an edge 68 of the back body portion 15 to form
a seal 70. The waist portions 16 and 17, when assembled form a
waist opening 20 for putting on and taking off the panty 12. The
waist opening 20 is surrounded at least in part by a waist elastic
22. The waist elastic 22 is stretched and attached to the waist
portion 16. The waist elastic 22 is released after attachment to
produce waist folds or pleats 24 to allow expansion of the waist
opening 20 so that the panty 12 can fit various sized women.
Because users of this invention generally prefer a brief style
panty, the waist portion 16 of the panty 12 preferably comes to the
navel and is even around the wearer's waist. Having the panty 12 at
this height and then drawing in the waist portion 16 with the waist
elastic 22 provides a snug fit. Alternative panty styles include
bikini (e.g. regular leg cut and french leg cut) and hipster (e.g.
regular leg cut or french leg cut).
[0017] Referring again to FIGS. 1 and 2, the front body portion 14
and the back body portion 15 together with the crotch portion 18
forms leg openings 28 and 30, respectively, which are generally
circular or oval in shape. The leg openings 28 and 30 are each
surrounded at least in part by leg elastics 32 and 34,
respectively. The leg elastics 32 and 34 are stretched and attached
to the front and back body portions 14 and 15 and the crotch
portion 18. The elastics are released after attachment to produce
leg folds or pleats 36 to allow expansion of the leg openings 28
and 30 to fit various sized legs.
[0018] The front body portion 14 is usually divided into a front
upper portion 40 and a front lower portion 42. Similarly, the back
body portion 15 is divided into a back upper portion 41 and a back
lower portion 43. The upper portions 40 and 41 are preferably
designed to include body elastics 44 which are capable of
stretching to allow the wearer to put on the panty 12 and then
readily resume the body elastic's normal contracted form. This
ensures a close or snug fit to different body and size forms. A
number of body elastics 44 are positioned on both the front and the
back portions 40 and 41, respectively, at positions between the
waist opening 20 and the leg openings 28 and 30, so that the panty
12 fits the wearer better, particularly around the body. The lower
body portions 42 and 43 do not necessarily require elastics. If the
outer cover incorporates the body elastic, the basis weight of the
outer cover and body elastic laminate may be as high as 5 osy.
[0019] In reference to the crotch portion 18 of FIG. 1, the
functional total capacity of normal pads worn during the menstrual
cycle ranges from about 12 grams to about 63 grams. More typically,
the capacity of the pads is above 20 grams. The marketing names
associated with such pads include "thin maxi", "maxi", "thick maxi"
and "super maxi". These will be referred to as maxi pads. The
entire absorbent core normally contained in a maxi pad and which is
used during medium to high menstrual flow periods in the panty 12
is the "primary" absorbent 45. The absorbent which is associated
with the crotch portion of the current invention is the "secondary"
absorbent.
[0020] The crotch portion 18 of the panty 12 consists of an
absorbent barrier composite 46. The absorbent barrier composite 46
further consists of a liquid barrier 48 and a secondary absorbent
50. Preferably, the thickness of the crotch portion 18 is less than
about 4 mm. The thickness is measured on a 4 inch (102 mm) square
sample (leg elastics removed) with a Mitutoyo Digamatic Indicator
using a 3 inch (76 mm) diameter acrylic platen and assembly to
produce a pressure of 0.05 psi. The liquid barrier 48 is needed to
prevent liquid strike through onto the outer clothing when leakage
occurs on. the panty 12. The liquid barrier 48 is located on the
inside of the crotch portion 18 and consists of a liquid impervious
film such as polyethylene. Use of only the film would be hot and
uncomfortable, would not be durable enough to withstand changing of
pads and would smear any menses which leaked off of the primary
absorbent 45. Any film crotch material in the prior art that is
elastic is nominally undesirable for the attachment of a pad since
the stretch could detach the pad. Therefore, it is desirable to
associate the secondary absorbent 50 with a liquid barrier 48 which
is nonelastic.
[0021] The secondary absorbent 50 should have a liquid capacity
great enough to absorb leakage of menses from the primary absorbent
45. The secondary absorbent 50 should preferably have a capacity
(described below) and a thickness substantially less than that of
the primary absorbent 45, thus providing a nonbulky and flexible
fit. The capacity of the secondary absorbent 50 should have a total
capacity of about one-half of the primary absorbent 45. Preferably,
the secondary absorbent 50 should have a total capacity of at least
about 3 grams and not more than 6 grams. More preferably, the total
capacity of the secondary absorbent 50 should be from about 4 grams
to about 6 grams. However, the basis weight of or the type of
secondary absorbent 50 should be adjusted to provide resistance to
flexibility of less than around 400 grams.
[0022] The absorbent barrier composite of the present invention has
a low stiffness. The low stiffness allows the absorbent and barrier
to remain attached to the conformable outer cover which conforms to
a wide range of body sizes and shapes. Preferably the absorbent
barrier composite has a stiffness of less than 400 grams along any
axis tested, more preferably less than 300 grams along any axis and
less than 100 grams along the axis parallel to the waist opening in
the invention.
[0023] The secondary absorbent alone will have a stiffness of less
than 250 grams and preferably less than 100 grams along any axis
and more preferably less than 75 grams along the axis parallel to
the waist opening in the invention.
[0024] The stiffness of the absorbent barrier composite is measured
by peak bending stiffness. Peak bending stiffness is measured by
INDA Standard Test method IST 90.3-92-Standard Test Method for
Handle-O-Meter Stiffness of Nonwoven Fabrics. The nonwoven to be
tested is deformed through a restricted slot opening by a blade,
and the required force is measured. This force is a measure of both
flexibility and surface friction of the absorbent.
Apparatus
[0025] The test apparatus is an Electronic Digital Read-Out
Handle-O-Meter, Model #211-5 equipped with flat plates. The
apparatus is available from Thwing-Albert Instrument Company in
Philadelphia, Pa.;
Number and Preparation of Samples
[0026] For each procedure for this test, five samples should be
prepared according to the method described in IST 90.3-92. For
tests involving the absorbent barrier composite, the specimen
should include all structural components of the absorbent barrier
composite including any materials or methods used to bond that
composite together. For tests of the secondary absorbent only, the
specimens should be all structural components of the secondary
absorbent including materials or methods for bonding that secondary
absorbent together.
Procedure
[0027] The procedure should be conducted as described in IST
90.3-92. The procedure makes provisions for altering specimen
dimensions if resultant grams readout exceeds the 100 gram capacity
of the instrument. Reduction in sample size to result in a read-out
within the range of the instrument may be necessary for materials
falling in the range of the above description. Conduct all such
modifications as described in IST 90.3-92 and use the test unit
conversion described in section 7.1 of IST 90.3-92. The gap should
be set at 0.25 inches (6 mm) as described in section 10.1 of the
IST 90.3-92. The absorbent barrier composite should be tested along
an axis parallel to the direction in which the absorbent composite
was manufactured (so-called machine direction) as well as the axis
perpendicular to the direction of the absorbent composite's
manufacture (so-called cross direction). In addition each side
should be tested along each axis. These steps are detailed in
sections 10.1 through 10.10 inclusive in IST 90.3-92.
Calculations
[0028] The maximum reading for each specimen is recorded per IST
90.3-92 section 10.3. The five values are averaged for each axis
and side condition tested. The results are reported as maximum
grams reading for each specimen. This differs from the millinewtons
called for in IST 90.3-92 sections 11 and 12. The average of all
five values for each condition is calculated.
[0029] The total capacity of the primary absorbent 45 and the
secondary absorbent 50 are determined as follows. Any panty
adhesive release paper is removed from the pad to be tested. The
total capacity of the primary absorbent 45 is determined using the
entire napkin minus any release paper. The total capacity of the
secondary absorbent 50 is determined using the absorbent barrier
composite 46 of the panty 12 and the outer cover 13. The specimen
is weighed to the nearest 0.1 gram and acclimated at standard
relative humidity and temperature for two hours. The specimen is
then submerged in a beaker of sterile saline (0.9% sodium chloride
solution obtainable from the Baxter Travenol Company of Deerfield,
Ill.), such that the specimen is totally submerged and is not bent
or otherwise twisted or folded. The specimen is submerged for 10
minutes. The specimen is removed from the saline and suspended for
two minutes in a vertical position to allow the saline to drain out
of the specimen. The specimen is then placed body facing surface
down onto an absorbent blotter, such as filter paper #631 available
from the Filtration Science Corp, Eaton-Dikmena Division of Mount
Holly Springs, Pa. A uniform 17.6 grams per square centimeter load
is placed over the specimen to squeeze excess liquid out of the
specimen. The absorbent blotter is replaced every 30 seconds until
the amount of liquid transferred to the absorbent blotter is less
than 0.5 grams in a 30 second period. The specimen is then weighed
to the nearest 0.1 gram and the dry weight of the specimen is
subtracted from the final wet weight. The difference in grams is
the total capacity of the specimen.
[0030] In construction of the absorbent barrier composite 46, the
liquid barrier 48 should retard the movement of the liquid through
the absorbent barrier composite 46 by making the barrier liquid
resistant to penetration normally encountered under wearing
conditions. The composite may be rendered liquid impermeable by any
method well known in the art such as coating the secondary
absorbent 50 or by securing a separate liquid impermeable material
to the secondary absorbent 50. Alternatively the liquid barrier 48
consists of a liquid impervious film or foam which is pervious to
water vapor under normal wearing conditions. More preferred, the
liquid barrier 48 has a water vapor transmission rate of at least
about 3500 grams/m.sup.2/day measured by ASTM E96-92. One example
of a suitable film is a 39.4 grams per square meter microporous
film produced by Mitsui and sold by Consolidated Thermoplastics
(CT) under the tradename of ESPOIR.RTM. N-TAF-CT.
[0031] The secondary absorbent 50 may be any construction which is
generally compressible, conformable, non-irritating to the wearer's
skin, capable of absorbing and retaining menstrual fluid.
Optionally, the secondary absorbent 50 has first and second opposed
faces and includes an absorbent rich layer 51 and a support layer
53. The absorbent rich layer 51 may be manufactured in a wide
variety of sizes and shapes (e.g., rectangular, hour-glass, etc. )
and from a wide variety of liquid absorbent materials, such as
fiberized wood pulp. Examples of other suitable absorbent materials
include creped cellulose wadding, absorbent foams, absorbent
sponges, superabsorbent polymers, or any equivalent material or
combination materials. The support layer 53 may be any construction
which is generally resistent to deterioration by liquids while
being conformable, non-noisy and capable of holding the absorbent
rich layer 51 in place.
[0032] Alternatively, the absorbent rich layer 51 can range from 30
to 80 gsm 1:1 blend of northern hardwood pulp and southern softwood
pulp. The support layer 53 can be a 12-15 gsm spunbond. The pulp
layer is hydroentangled through the spunbond. Alternatively, the
combined layers may then be microcreped. The liquid barrier 48 and
the secondary absorbent 50 are bonded together using an adhesive 72
add-on of 3 to 7 gsm. Optionally, the absorbent rich layer 51 is
bonded to the barrier of the absorbent barrier composite 46. This
arrangement permits improved attachment, removal and reattachment
of the primary absorbent 45 to the panty 12. The liquid barrier 48
is bonded to the outer cover 13 on the inside of the panty with an
adhesive 74 add-on of 5 to 10 gsm. The liquid barrier 48 may be an
adhesive film which bonds the secondary absorbent 50 to the outer
cover 13. A suitable adhesive for both applications includes, for
example, National Starch NS 34-5561 hot melt adhesive which is
available from National Starch and Chemical Company located in
Bridgewater, N.J.
[0033] The width of the crotch portion 18 between the leg elastics
32 and 34 should be wide enough to lay the primary absorbent 45
between the edges without having the primary absorbent 45 obstruct
the leg elastics. This allows the leg elastics 32 and 34 to
contract and draw up the sides of the crotch to accommodate the
depth of the primary absorbent 45 being used and give surface area
within the crotch portion 18 to contain leakage from the primary
absorbent 45.
[0034] The minimum width of the crotch portion 18 should not be so
wide as to seem bulky or uncomfortable, but a suitable width is at
least about 2.75 inches (70 mm) between the leg elastics. The
minimum width is advantageous from about 3 inches (76 mm) to about
3.5 inches (89 mm). Optionally, the width is about 3 inches (76
mm). Preferably, the leg elastics 32 and 34 are from about 0.375
inch (10 mm) to about 0.625 inch (16 mm) wide. More preferably, the
width is about 0.5 inch (13 mm). Preferably, ruffle material on the
edge of the leg openings 28 and 30 outside the leg elastics 32 and
34 is less than about 0.25 inch (6 mm). More preferably, the ruffle
material is less than about 0.125 inch (3 mm). It is most desirable
to eliminate the ruffle material from the edge of the leg openings
28 and 30. The overall width of the crotch portion 18 includes the
width between the leg elastics 32 and 34, the width of the leg
elastics 32 and 34 and the ruffle material outside the leg elastics
32 and 34 to the edge of the leg openings 28 and 30. Preferably,
the overall width of the crotch portion 18 should be at least about
4 inches. (102 mm). The width of the absorbent barrier composite 46
is sized in relation to the width of the crotch portion 18.
Preferably, the width of the composite 46 is at least the width of
the crotch portion 18 between the leg elastics 32 and 34. More
preferably, the width is equivalent to the width of the crotch
portion 18.
[0035] The overall length of the absorbent barrier composite 46
should be adequate to extend beyond the ends of the primary
absorbent 45 to help prevent liquid strike through at these points
when sleeping or sitting. This overall length is at least about 15
inches (382 mm) thus extending beyond the crotch portion 18 along
the longitudinal centerline A-A of the panty 12. Alternatively, the
length should be in the range of about 15 inches (382 mm) to about
19 inches (484 mm). Optionally, the length of the composite 46 is
about 17 inches (433 mm).
[0036] The width of the absorbent barrier composite 46 beyond the
crotch portion 18 should be at least as wide as the width of the
crotch portion 18. The width of the absorbent barrier composite 46
could be narrowed beyond the crotch portion 18 but may compromise
the leakage containment. More preferably, the width is from about 5
inches (127 mm) to about 12 inches (306 mm), alternatively from
about 5.5 inches (140 mm) to about 7.5 inches (191 mm). Optionally,
the width is about 6.5 inches (165 mm).
[0037] The present invention contemplates various shapes of the
composite 46. One preferred composite has a non-rectangular shape
with rounded ends which provides extensive coverage in the seat of
the finished panty 12. Another preferred absorbent barrier
composite 46 embodiment is rectangular in shape with rounded ends.
The essentially rectangular-shaped absorbent barrier composite 46
is more preferred since it can be squared off at the ends to
provide a smoother appearance in the back of the panty 12. Line 76
may be embossed or printed on the inner surface of the crotch
portion 18 to aid in placement of the primary absorbent 45 by the
wearer.
[0038] Referring to FIG. 3, the waist elastic 22 is shown covered
with a waist liner 26. Referring to FIGS. 3 and 4, the leg elastics
32 and 34 are shown covered by the absorbent barrier composite 46
and a leg liner 38. Referring to FIG. 3, the body elastic 44 is
shown covered with a body liner 80. The liner consists of a
nonwoven or other soft material for contacting the wearer's
skin.
[0039] The position and the shape of the leg openings 28 and 30 are
important to avoid tightness in the crotch and groin area of the
wearer, to obtain adequate buttocks coverage, and to prevent the
panty 12 from tilting forward, i.e. tilting such that the front
waist edge dips lower in relationship to the back waist edge. FIG.
1 illustrates the most preferred design for leg fit and buttocks
coverage. The shape of the curve across the top of the leg may be
considered. If the curve is too deep, the panty 12 will shift
downward and backward resulting in a short front waist, increased
back length and bagginess in the seat of the panty. This causes the
panty 12 to appear tilted when worn as evidence by an unevenness
around the waist of the wearer.
[0040] The leg openings 28 and 30 are important to the correct
functioning of the panty 12. With the panty 12 laid out flat as in
FIG. 1, the majority of the back half of the leg opening preferably
forms a straight line. More preferably the back edge of the leg
opening is straight for a length, .theta., of at least about 70% of
the length of the entire back half. The straight section .theta. of
the back half of the leg opening should form an acute angle with
the longitudinal centerline, A-A, of the panty 12. More preferably,
the line, .theta., forms an angle, .alpha., with the centerline A-A
of the panty 12 of between about 50.degree. and 65.degree. and most
preferably about 60.degree.. The majority of the edge of front half
of the leg opening including lengths .beta. and also preferably
forms a straight line. More preferably, the lengths of edge .beta.
and of the leg opening is straight for at least about 70% of the
length of the front half. The straight section .beta. of the front
half of the leg opening should form an angle with the centerline of
the panty 12 of between about 75.degree. and 110.degree. and most
preferably about 90.degree..
[0041] Likewise, the shape of the arc at the inner groin area is
important. If the arc is too shallow, tightness may be experienced
at the inner groin area. The preferred narrow crotch width reduces
coverage of the buttocks. To compensate for such reduction, the
back curve is preferably adjusted downward. The arc between the
crotch edge of the leg opening and the back edge of the leg opening
should start slightly in front of centerline B-B of the panty 12,
see FIG. 1. This allows the leg elastic to be positioned below the
lower edge of the buttocks and helps prevent the panty 12 from
riding up when walking. This means that the straight portion of the
inner edge of the leg opening is entirely forward of the panty 12
centerline B-B.
[0042] The waist, leg and body elastics 22, 32, 34 and 44,
respectively, are attached to the panty 12 on the outer cover 13 in
generally a stretched state by means known in the art, such as
ultrasonic bonded, heat/pressure bonded or adhesively bonded.
Materials suitable for elastics include a wide variety including
but not limited to elastic strands, yarn rubber, flat rubber,
elastic tape, film-type rubber, polyurethane and elastomeric,
tape-like elastomeric or foam polyurethane or formed elastic scrim.
Each elastic may be unitary, multipart or composite in
construction.
[0043] The waist elastic 22 is about 0.5 inch (13 mm) wide. The
elastic may comprise threads, ribbons, a film or composite. The
threads or ribbons may be multiple and may be applied as a
composite. Preferably, the waist elastic is threads, more
preferably four threads are used as the elastic and the threads are
spaced about 0.17 inch (4.3 mm) apart. The threads may be made of
any suitable elastomeric material. One suitable material is spandex
such as Lycra.RTM. threads available from Dupont located in
Wilmington, Del. Suitable waist elastics include threads having a
total decitex (g/10000 m) of about 3760 for 0.5 inch (13 mm) wide
elastic. Adhesive 74 is used to bond the elastic to the outer cover
13 and the waist liner 26. A suitable adhesive includes, for
example, Findley H2096 hot melt adhesive which is available from
Findley Adhesives located in Milwaukee, Wis.
[0044] The leg elastics 32 and 34 are about 0.5 inch (13 mm) wide.
The elastic may comprise threads, ribbons, a film or composite. The
threads or ribbons may be multiple and may be applied as a
composite. The front and crotch leg elastics may be threads,
preferably numbering three threads which are spaced about 0.17 inch
(4.3 mm) apart. Back elastics numbering up to six threads should
have a width of about 0.75 inch (19 mm) and a spacing of about 0.15
inch (3.8 mm) apart. The threads may be made of any suitable
elastomeric material. One suitable material is spandex such as
Lycra.RTM. threads available from Dupont located in Wilmington,
Del. Suitable leg elastics include threads having a total decitex
(g/10000 m) of about 3760 for a 0.5 inch (13 mm) wide elastic.
Adhesive 74 is used to bond the elastic to the outer cover 13 and
to the leg liner 38.
[0045] To provide a snug leg fit and to draw up the sides of the
crotch portion 18 to form the primary absorbent cradle, the leg
elastics 32 and 34 are applied to the outer cover 13 under an
elongation of about 250%. Preferably, during the application of the
elastics, the elastics 32 and 34 are segmented into multiple
segments, each segment being elongated to a different degree and
applied to the outer cover 13. In the case of two segments, the
front segment is elongated less than the back segment. In the case
of three segments, the front and crotch segments are elongated less
than the back section. Preferably, the front and crotch segments
are elongated to about 150% and the back segment is elongated to
about 250%. The segmenting and differing tensions allow easier pad
attachment, less tightness in the groin area, and less bunching of
the crotch portion 18 caused by high leg elastic retraction. The
back leg elastic is under higher elongation to help keep the seat
of the panty from creeping up with movement during use.
[0046] The body elastics 44 circumferentially surrounding the body
portions 14 and of the panty 12 act independently to conform to the
contours of various body types and builds. This provides a smooth,
snug, and comfortable fit within a given hip size range. Using
higher elongation, closer spacing, and higher cross-sectional area
in the waist elastic 22 than in the body elastics 44, the panty 12
takes on a rounded shape and provides good waist fit across the
waist to hip ratios encountered.
[0047] Preferably, in the front body portion the body elastics 44
adjoin both the waist elastic 22 and leg elastics 32 and 34. In a
panty 12, the body elastics 44 are about 6.5 inches (166 mm) wide
in the front and about 6.0 inches (153 mm) wide in the back. The
body elastics 44 are preferably spaced about 0.25 inch (6 mm)
apart.
[0048] The absorbent barrier composite 46 which extends up the
front and/or back body portions toward the waist portion is
conformed to the wearer's body by the body elastic 44. The
transition from the front and back lower portions to the front and
back upper portions is thus smoothed.
[0049] The waist elastic 22 is desirably under a greater tension
per unit width than the body elastics 44 in the upper body portion
40 to provide the snug waist fit over the range of waist to hip
ratios of the various body shapes. In the preferred embodiment, the
tension on the waist elastic 22 is coordinated with the tension of
the body elastics 44 to form a snug fit about the waist opening
while providing a smooth transition from the upper body portion 40
to the waist portion 16.
[0050] In the front and back body portions 14 and 15, the leg,
waist and/or body liners may be expanded to cover the interior of
the body portions 14 and 15. The leg, waist and/or body liners may
exclude the center crotch portion 18 which is covered by the
application of the absorbent barrier composite 46. In the body
portions where the absorbent barrier composite 46 overlaps the
liner, the composite is applied on top of any liner present so as
to contact the wearer.
[0051] An acceptable range for the waist elastic tension is from
about 380 grams to about 1000 grams. More preferably, the tension
at the waist is from about 575 grams to about 750 grams. The
preferred leg elastic tension is from about 375 grams to about 1000
grams. More preferably, the tension at the leg is from about 500
grams to about 700 grams. The preferred hip elastic tension is from
about 500 grams to about 850 grams. More preferably, the tension at
the hip is from about 650 grams to about 750 grams. The waist and
leg tensions are determined as follows. The appropriate gauge rod
distance is selected from Tables 1 and 2 for a given panty size and
desired location measurement. This rod distance is the distance
between the top of the upper peg and the bottom of the lower peg on
the Chatillon DFG-2 Tensile Tester.
1TABLE 1 Gauge Rod Distance Pant Size Waist Leg 5/6 354 mm 278 mm
7/8 392 mm 306 mm 9/10 468 mm 345 mm
[0052]
2TABLE 2 Gauge Rod Distance Pant Size Waist Leg 5/6/7 371 mm 288 mm
8/9/10 445 mm 328 mm
[0053] Measurements are recorded on the tester in kilograms, the
HOLD/NORM switch is set at "NORM", the T/C switch is set at "T"
(tension). The samples are conditioned and the testing is conducted
in a standard laboratory atmosphere of a temperature of
23.+-.2.degree. C. and a relative humidity of 50.+-.5% RH.
[0054] For determination of the waist tension, the edge along the
bonded seam of the panty 12 is placed over the upper peg of the
tester. The panty 12 is allowed to hang freely from the upper peg
and the weight of the specimen is tared out.
[0055] The lower block is lifted upwards and the opposing waist
edge along the bonded seam is placed over the peg of the lower
block. The block is lowered until the magnet of the tensile tester
locks into place. The tester is activated and timed for two
minutes. At two minutes, the tension displayed on the gauge is
recorded. The tension in kilograms is converted to grams and the
panty 12 is removed.
[0056] For determination of leg tension, the edge along the bonded
seam near the crotch fold is placed over the upper peg. The panty
12 is allowed to hang freely from the upper peg and the weight of
the specimen is tared out.
[0057] The lower block is lifted upwards and the bonded seam along
the opposing leg opening edge is placed over the peg of the lower
block.
[0058] The block is lowered until the magnet of the tensile tester
locks into place. The tester is activated and timed for two
minutes. At two minutes, the tension displayed on the gauge is
recorded. The tension in kilograms is converted to grams and the
panty 12 is removed. This measurement represents the right leg
tension. The test is repeated for the left leg tension.
[0059] For determination of hip tension, the top and bottom side
seams of the body portion of the panty 12 are placed in the upper
and lower 8 inch wide jaws of an Instron Model 1122 equipped with a
Sintech software system and the Interactive Materials Analysis
Program (IMAP).
[0060] The tension program stretches the elastic body portion at a
rate of 500 mm/minute until 1000 grams is reached. The crosshead
then returns to the starting position and repeats a second cycle.
The stress-strain graph can be plotted and tension data points
printed at 50, 60, 70, 80, 90% of the full stretch (defined as
length at 1000 grams) for first and second load and unload cycles.
The tensions were taken from the second cycle unload values at
about 85% of full stretch.
[0061] The side seams 64 and 70 may be made on the inside or
outside of the panty 12 or formed flat against the panty 12 to give
a more finished look to the panty 12 and to prevent the seams 64
and 70 from showing through clothing. Optionally, the lateral edges
60, 62, 66 and 68 of the front and back body portions are not
overlapped but are formed flat and extend out laterally. The side
seams 64 and 70 should be minimal in width while providing
sufficient strength to be pulled up and down many times over a 24
hour wear period.
[0062] The side seams 64 and 70, respectively, of the outer cover
13 are sealed by means known in the art, such as ultrasonic
bonding, stitching, heat/pressure bonding or adhesive bonding. The
maximum seam strength attainable is dependent upon materials used,
bond pattern, pond width, and process settings of dwell time,
power, and pressure. Suitable side seams typically utilize
ultrasonic bonding to achieve a seam strength of at least 5 kg.
[0063] The seams 64 and 70 may have an unbonded portion outboard of
the bonded area to provide for a soft edge to the seam. This
unbonded portion can ranged from 2 to 3 mm in width. Alternatively,
the entire seam width (bonded portion plus unbonded portion) may be
less than about 0.25 inch (6 mm). If the seam is trimmed or cut
close to the outer edge of the bond area, a sharp edge is produced
along the seam edge which can catch on clothes or be irritating to
the wearer's skin.
[0064] The panty 12 was compared to panties constructed of cotton
and panties having a barrier but no secondary absorbent 50.
Seventeen women were retained for this comparison. Each woman wore
a selected maxi pad with each panty type until the pad leaked onto
that panty type. Loose-fitting cotton shorts were worn by each
woman over the panty which could be worn under their normal
loose-fitting clothing. At the end of each test, the pad, panty and
cotton shorts were collected. The pad, panty and shorts were
photographed. The results of the comparison found that cotton
panties had leakage to outer garments in 35.3% of the women,
panties with barriers but no secondary absorbent 50 had leakage in
41.2% of the women and the panty 12 of this invention had leakage
in only 23.5% of the women.
[0065] Having thus described the invention in full detail, it will
be readily apparent that various changes and modifications may be
made without departing from the spirit of the invention. All such
changes and modification are contemplated as being within the scope
of the present invention, as defined by the following claims.
* * * * *