Note: Descriptions are shown in the official language in which they were submitted.
BAC~GROU~D OF TY.E I~IVE~ITIO~
2~ This invention relates generally to lmprovements in
a disposable absorben~ garment inter.ded to be used to receive
or tending to receive disc~arge from the body, and in particular
relates to disposable diapers, incontinent pads, and the like
designed to be worn on the body and haYing a contractable thigh-
2S encircling portion whioh conforms to the con~ours of the body
and permits movement of the bodv while maintaining a sea~ with
the body in motion. This invention further relates to means to
secure such a garment to the body of the wearer and more
particularly to means adapting the thigh-encirclin~, portions of
~^ 8aid ~arment to an adult le~ eonfi~ur~tion.
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Absorptive devices such as disposable incontinent
briefs are well-known in the art. These devices are used
to absorb liquid from the human body and retain that liquid
until the garment can be disposed of. Present disposable
incontinent briefs are frequently flat composite shee-ts
which are fitted to a wearer in the fla-t state or incorporate
geometric folding to achieve a suitable body shape. A major
in-use problem with such prior art articles is that gaps
between the brief and the wearer's legs tend to develop due
to the semi-rigid nature of the absorbent body, especially
after the brief has been worn for some time, or during a
period of activity when the garment is able to flex or
shift on the wearer's body. These gaps permit leakage from
a disposable garment, thereby creating damp outer clothing
or bedding around the wearer.
Although these problems have been allevia-ted some-
what in the case of infant's diapers, the fitting of such a
garment to an adult presents problems not found in the
creation of a garment suitable for an infant.
First, since the legs of an infant characteristic-
ally form a substantial angle with the lateral line of the
trunk of the body, it has been observed that a diaper having
straight-line elastics such as those described in U.S. Patent
3,860,003 issued to Buell On January 14, 1975, can be
secured to the infant's body by a single securement means
on either side of the diaper. This is true because a circle
drawn around the top portion of the diaper on the baby's
body and a circle drawn around the thigh seal portion very
nearly intersect at one tangent point, so that a single
securement means placed at that point will effectively secure
the waist and the thigh portions of the diaper simultaneously.
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However, in an adult, whose legs in the normal position are
generally substantially parallel to each other and to the
lateral line of the trunk of the wearer's body, a circle
drawn a-t the edge of the garment about the wearer's thigh
and substantially perpendicular to the wearer's thigh as
defined hereinafter does not at any point approach a second
circle drawn around the top portion of the garment secured
about the wearer's waist or trunk. Thus, unlike prior art
devices primarily designed to fit an infant, a single
securement means on each side of the article will not serve
to conform the garment to an adult wearer's waist while
effectively securing the garment against leakage at the
thigh area.
Second, as also revealed in the aforementioned
Buell patent, it is desirable to construct an incontinent
brief with elasties which are parallel to each other, and
which lie along each edge of the croteh. This simplifies
the manufacture of an incontinent brief, since the elastic
can be applied in the machine direction when the article is
manufactured. Brief elastics having a substantially
straight-line contractable dimension have advantages in
use as well. A substantially straight-line elastic member
in the region of the croteh allows a single article to
contract substantially along this dimension, so that the
dif~ering crotches of various individuals are accommodated
to provide a snug fit of the article in the crotch area of
th- ~tearer. (This development of the prior art is in con-
trast to a great number of similar articles, such as conven-
tional underwear, deploying elastic members which have no
0 substantial straight-line element, and which generally
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conform around a cut-out in the brief.) However, a corre-
sponding problem in prior art structures employing parallel
straight-line elastic members having a substantially longi- -
tudinal contractable dimension and a sing]e securement means
to secure the wais-tband and legband portions, especially in
an adult garment where the crotch width mus-t necessarily
be much less than the width of the portion of the garment
which wraps around the trunk of the wearer, is that one can-
not draw the functional ends of the straight-line elastic
member effectively together around the thigh of the wearer
to form a seal which is substantially perpendicular (as
defined hereinafter) to the thigh bone of the wearer with-
out unduly compromising the fit of the waistband portion
about the wearer's trunk. As pointed out above, a seal
which is not substantially perpendicular to the thigh bone
of the wearer will not adequately contain the material which
is to be absorbed or held by the brief.
In summary, devices can be found in the prior art
which have straight-line elastic members on either side of
the crotch; prior art structures having roughly the same
can be found wherein a plurality of fasteners are used on
either side of a garment to attach it to the body of a
wearer. However, prior art is not available to solve the
specific problems which are encountered when straight-line
elastic mernbers are used in a garment which requires a
plurality of fastening means on either side of the body of
the wearer in order to seal the garment to the thigh while
providing a fit to the trunk of the wearer as well.
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SUMMARY OF THE IMVENTION
The present invention relates to an absorbent
brief having a moisture-impervious backsheet, a moisture
pervious topsheet and a moisture-absorbent member
interposed between said backshee-t and said topsheet, the
backsheet and topsheet having substantially identical
rectangular configurations with oppositely disposed leg
cut-out areas in the central portion of each side edge,
the leg cat-out areas defining a crotch portion interposed
and integrally joined with trunk-encircling portions at
opposite ends of the brief, an elastic member joined to
each side of the crotch portion, said elastic member being
in contractable condition when joined thereb~ causing the
crotch portion o~ the brief to have a tendency to gather,
each of said elastic members extending through the crotch
portion in a straight line and terminating in functional
endpoints in the end area of the trunk-encircling portions
nearest the crotch portion, upper securement means
including a tape attached to and extending from each side
edge of one of the trunk-encirc].ing portions near the end
edye thereof. The novel feature in this absorbent brief
comprises (a) lower securement means including a tape
attached to and extending from each side edge of said one
of said trunk-encircling portions, (b) each of said lower
securement means being spaced inwardly toward the crotch
portion with respect to said upper securement means, tc)
each of said lower securement means being attached to an
anchoring region, (d) each of said anchoring regions being
defined by a side edge of the brief and two line segments,
each of said line segments extending from the functional
lendpoint nearest each lower securement means of each of
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said elastic members to the nearest side edge of the
brief, (e) the first of said line segments extending
outwardly from the functional endpoint at an angle of at
least about 90 as measured from the elastic member
terminating at said functional endpoint, (f) the second of
said line segments extending outwardly from the functional
endpoint at an angle no greater than about 140 as
measured from the elastic member terminating at said
functional endpoint, (g~ a securement vector lying within
each of said anchoring regions and extending from said
functional endpoints to the lower securement means, (h)
whereby the lower securement means when attached to the
opposite trunk-encircling portion when said brief is in
use functions to form an effective thigh seal snugly
around each leg of a wearer in a plane substantially
perpendicular to the thighbone of the wearer, (i) the line
of each of said thigh seals being through its respective
elastic member, securement vector and lower securement
means.
When the brief is donned by encircling the thigh
of the wearer with the lower part of one trunk-encircling
portion of the brief, the user-actuated portion of a
securement means which is already anchored on the
anchoring portion as above defined is further secured to
the lower part of the second trunk-encircling portion of
the brief in a position effective to achieve the desired
seal. The site of attachment of the user-actuated portion
of the lower securement means is somewhere on the backsheet
of the second trunk-encircling portion, the exact site
3~ depending on the particular thigh, trunk, and crotch
,dimensions of the wearer.
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As a result of the critical placement of the
anchored portion of the thigh securement means on t'ne
indicated segment of the brief, a seal is generally
defined by the following structures: the elastic member; a
portion of the brief material lying along a tensioned line
between the functional endpoint of the elastic member
which defines the apexes described above and the anchored
portion of the thigh securement means; and the user-
actuated portion of the thigh securement means. If the
user-actuated portion of the thigh securement means is
attached to the brief transversely outward of the elastic
member, the portion of brief material between that point
of attachment and the second functional end of the elastic
forms a portion of the seal as well. It is of the essence
in this invention that the elements of the seal defined
above lie substantially in a plane perpendicular, as
defined hereinafter, to the thigh bone of the wearer when
the brief is in use.
It should be noted that while the brief requires
further means to conform it about the trunk of the wearer,
such means are known in the art and are not within the
scope of this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
While it is believed that the invention will be
better understood from the description appearing below of
preferred embodiments of the present invention, it is
understood that the invention herein is defined by the
claims ~7hich particularly point out and distinctly claim
the subject matter which is regarded as forming the
present invention.
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Figure 1 is a plan view of a preferred embodiment
of the invention with its elastic members in an extended
condition and the wearer contacting portion of the brief
facing the viewer.
Figure 2 is a plan view of the device of Figure 1,
illustrating a preferred embodiment of the invention, with
the elastic in an unstressed condition.
Figure 3 is a plan view of an alternate embodiment
of the invention, with its elastic members in an extended
condition, and with its wearer contacting portion facing the
viewer.
DETAILED DESCRIPTION OF THE INVENTION
For the purposes of this specification, an "adult"
is defined as any person having thigh bones which are orien-
ted substantially parallel to the lateral line of the body
during a majority of the wearer's activities. This distin-
guishes an "adult" from an infant, and particularly from
an infant who has not yet learned to walk, for the legs of
such an infant usually form a substantial angle with respect
to the lateral line of its body during a majority of the
wearer's activities. Thus, an "adult" as defined herein
may include youths and teenagers who have leg orientations
similar to those of a mature person.
A plane which is "substantially perpendicular" to
the thigh-bone of the wearer is defined herein as a plane
forming a plane angle of hetween about 0 degrees and about
~0 degrees with respect to a plane which is geometrically
perpendicular to the thigh-bone of the wearer.
Figures 1 and 2 represent a par~i~ularly preferred
embodiment of the present invention having side notches
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which receive the legs of the wearer in order to provide a
brief having a well-tailored contour when it is worn.
The absorbent brief forming the present invention
is comprised generally of moisture-impervious backsheet 1,
moisture-pervious topsheet 2, and moisture-absorben-t member
3 therebe-tween. The backsheet 1 and topsheet 2 are prefer-
ably secured to one another about absorbent member 3 at the
periphery of the article which is generally indicated by 9.
The dimensions of the brief of Figure 1 are more
particularly described by a longitudinal dimension 4, a
transverse dimension 5, a crotch portion 8 having a crotch
length 22, a crotch width 21, a cut-out width 20, and trunk-
encircling portions 7 and 27. It is to be understood that
the diaper may be worn with either trunk-encircling portion
7 or trunk-encircling portion 27 forward, although in the
preferred mode of use the trunk-encircling portion 7 forms
the rear portion of the garment when it is worn. Crotch
portion 8 of the article is provided with a plurality of
elastic members 10, preferably one on each side of the wear-
er's crotch, and generally disposed near the edge of thegarment. Each elastic member 10 has endpoints 11 and 12,
hereinafter referred to as "functional endpoints" because
it is appreciated that an end portion of elastic member 10
may be provided which is unable to gather or shirr the gar-
ment because it is either stiffened or unadhered to the art-
icle.
Absorbent member 3 of the brief can be made of any
of the absorbent materials known to those of ordinary skill
in the bandage art. For example: a multiplicity of plies
of creped cellulose wading; fluffed cellulosic fibers or
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air~laid wood pulp fibers sometimes known as air-felt; textile
fibers or other absorbent material. A particularly preferred
absorbent member 3 may be constructed following the teachings
of U.S. Patent 3,860,003 (the Buell patent). While in the
embodiment of Figure 1 absorbent member 3 lies generally
between elastic members 10 in the crotch portion of the brief
it is to be appreciated that this is not a requirement of
the present invention, so long as elastic members 10 are able
to contract the brief.
Moisture-impervious backsheet 1 is preferably a
flexible moisture-impermeable sheet comprised of a low den-
sity, opaque polyethylene web having a thickness of about
1 mil, such as the backsheet employed in the aforementioned
Buell patent. In the embodiment illustrated in Figure 1,
the backsheet 1 has a rec-tangular configuration with leg
cut-out areas 19 deviating from the rectangular configuration.
In this embodiment -the backsheet 1 extends beyond the peri-
phery of the absorbent body around the entire periphery
thereof. Brief side portion 9, defined generally by the
periphery of the backsheet extending beyond absorben-t member
3, is roughly four inches wide in the trunk-encircling
portions 7 and 27 and approximately one and one-half to two
inches wide in the crotch portion 8 of the brief.
Topsheet 2 is coextensive in area with backsheet 1.
One preferred embodiment of topsheet 2 is shown and described
in U.S. Pa-tent 3,929,135 issued to Hugh Thompson on
December 30, 1975. However, it is to be understood that the
invention does not require a particular type of topsheet, or
any topsheet at all.
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The elastic member 10 is operatively associated
with crotch portion 8 adjacent to brief side portion 9 in
an elastically contractable condition so that in a normally
unrestrained configuration, the elas-tic member 10 effectively
con-tracts or gathers the crotch material to provide an
elastic retraction line 13 colinear with the material of
elastic member 10 Attachment of the elastic members 10 to
achieve this result is also described in the aforementioned
Buell patent.
A comparison between Figuresl and 2 will illustrate
the function of the elastic members 10 on either side of the
crotch to adjust the length of the crotch to fit -the body of
a wearer. In Figure 1, wherein the elastic members are
stretched so that the entire garment lies substantially in a
plane, crotch portion 8 has a maximized crotch length
dimension 22. On the other hand, in Figure 2, where the
elastic is allowed to relax insofar as relaxation is per-
mitted by the material of the brief, the crotch length dimen-
sion 22' is roughly one-half as large as the identical dimen-
sion in Figure 1. The exact variance between the dimensions
22 and 22' will depend on how the side-notch and crotch are
dimensioned in a particular garment. As depicted by the
reference numeral 23, the material in the crotch is gathered
in Figure 2, but the width 21 of the crotch is substantially
unchanged between the two Figures. It has been found that
when the crotch is elastically contractable in its longitud-
inal direction without substantial transverse contraction,
the brief is well-suited to accommodate a wide range of sizes
without the need for measurements or mechanical adjustments.
The effective length of elastic member 10 in its
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stretched condition is that length available to contract.
The extremities of this effective length of elastic are de-
fined by functional endpoints 11 and 12. These functional
endpoints 11 and 12 may be distinguished from the actual
endpoints of the elastic, for it is apparent that portions
of the elastic may be so secured to the brief that they are
unable to contract, or loose ends of the elastic may be
allowed which do not contribute to the contraction of the
brief.
Upper securement means 14 may be provided by any
of a number of means well-known in the art, such as tapes,
an elastic band to which both ends of the brief are attached
(analoyous to the waistband of conventional underwear), snaps,
pins, and so forth. Likewise, it is to be appreciated that
lower securement means 15 can be any securement means which
can be used to attach two portions of the garment together
while it is being worn. One particularly preferred fastening
means is the tape fastening structure generally disclosed
in U.S. Patent 3,848,~94 issued to Buel], on November 19, 1974,
A critical feature of the present invention is the
placement of lower securement means 15. Lower securement
means 15 is anchored by a manufacturer's joint at its
anchored portion 25 to the brief within anchoring region 16,
which is defined by the edge portion of the brief 9 and by
line segments 17 and 18. First line segment 17 is bounded
at its transversely inward end by functional endpoint 11 of
the elastic member 10, and extends transversely outward from
func-tional endpoint 11 in the plane of the brief at an angle
a with respect to elastic member 10. Second line segment
18 similarly is bounded by functional endpoint 11 and extends
transversely ou-tward to the edge portion 9 of the brief in
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the plane of the brief at an angle ~ with respect to
elastic member 10. The angle ~ i~ preferably about 90 degre-
es, and the angle ~is preferably about 140 degrees when the
elastics are located within about one and one-half inches of
the lateral edge of the crotch portion of the diaper along
a majority of their length. Particularly preferred values
of ~ and ~ are about 116 degrees and about 125 degrees,
respectively.
When lower securement means 15 is anchored in
region 16, securement vector 24, a tension vector, defines
a por-tion of the brief between lower securement means 15 and
functional endpoint 11 which lies approximately in a plane
which is substantially perpendicular to the thigh of the
wearer when the brief is worn, forming a part of the thigh
seal.
To attach the brief to the body of the wearer, the
brief is placed around the cro-tch and trunk portions of the
wearer, upper securement means 14 is brought laterally
around the trunk of the wearer and secured to the other side
of the brief somewhere along the upper part of trunk-encir-
cling portion 27. Similarly, lower securement means 15 is
secured to the lower part of trunk-encircling portion 27.
I'he points of securement of upper and lower securement means
14 and 15 are thus variable, depending on the particular
body dimensions of the wearer in comparison to the dimensions
of the brief.
When the garment is donned and a-ttached as descri-
bed above, elastic member 10 lies along the inner portion of
the thigh of the wearer, and securement vector 24 lies along
a second portion of the wearer's thigh. If the point of
attachment of the user-actuated portion 26 of lower securement
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means 15 on trunk-encircling portion 27 is transversely
inward of the line defined by elastic member 10, securement
vector 24 overlies -that line and is held in that overlying
rela-tion by circumferential tension to complete the seal.
On the other hand, if the point of attachment of the user-
actuated portion 26 of lower securement means 15 is trans-
versely outward of a line defined by elastic member 10, the
material of the garment spanning the space between said
point of a-ttachment and functional endpoint 12 of elastic
member 10 completes the seal. When the brief is worn, these
portions of the seal are all approximately in a plane which
is substantially perpendicular to the thigh-bone of the
wearer, and form a substantially unbroken seal around the
thigh of the wearer. This thigh seal is resilient due to
the action of elastic member 10, which con-tracts along
elastic retraction line 13 to conform the seal to the thigh
of the wearer. Thus, this structure sa-tisfies the objects
of this invention to provide a thigh seal which lies
approximately in a plane which is subs-tantially perpendicular
to the thigh-bone of the wearer.
Briefs made according to this preferred embodiment
of the invention can conveniently be made in small, medium
and large sizes to accommodate the proportions of a wide
number of consumers. A medium-si~ed brief adapted to fit
the ordinary range of adult wearers having hip circumferen-
tial measurements in the range of about 32 inches to 44 inches
can be accommodated by a brief having a functional stretched
elastic length of about 8-9 inches, a longitudinal dimension
4 of about 33 inches, a transverse dimension 5 of about
25 inches, a crotch width 21 of about 9-1/2 inches, and
spacing between elastic members 10 across the crotch of
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about 8 inches. To accommodate the dimensions of a small
adult or teenage wearer, a brief may conveniently be dimen-
sioned with a functional stretched elastic length of about
8-9 inches, a longitudinal dimension 4 of about 28 inches,
a transverse dimension 5 of about 18 inches, a crotch width
21 of about 7 inches, and spacing be-tween elastic members
lO of about 6 inches across the crotch. A brief for large
adults may conveniently have the following dimensions: a
functional stretched elastic length of about 8-9 inches, a
longitudinal dimension 4 of about 40 inches, a transverse
dimension 5 of about 31 inches, a crotch width 21 of about
9-1/2 inches, and a spacing between elastic members 10 of
approximately 8 inches. While it is to be appreciated that
the invention is not limited to embodiments having these
dimensions, it has been found that these three brief sizes
will accommodate a selection of wearers ranging from adoles-
cents to rather large adults.
When a brief constructed in accordance with the
above "medium" dimensions was worn by a particular female
model, it was found that the separation between an upper
tape, located with its center about an inch below the top of
the brief, and the center of the thigh securement tape was
about 5-l/2 inches when an acceptable thigh seal was formed.
When the thigh seal was optimized, the tape separation for
this wearer ranged between about 6 inches and 8 inches.
Within this range, the angle of the plane of the seal with
respect to a plane perpendicular to the thigh-bone varied
between about 20 degrees and about 30 degrees. When the
angle of the plane of the seal exceeded about 40 degrees,
the seal was no longer adequate. These figures for a
single wearer are not intended to be descriptive of the en-
-tire range of brief wearers, but they illustrate that a brief
designed for adult wear must have independent means to
respectively secure the garment at the thigh and at the waist.
The optimum angle of the plane of the seal with
respect to a plane perpendicular to the thigh of the wearer
is an accommodation between the frequently conflicting goals
of providiny an effective thigh seal and providing a desir-
able overall fit of the brief to the wearer's body. The
ideal anyle from a sealing standpoint is nearly 0 degrees,
at which point the circumference of the seal is minimized.
The ideal angle from a fit standpoint would be much larger
for many persons to form an ideal brief-shaped garment. The
angles encompassed by the definition of "substantially
perpendicular" in this specification represent the middle
ground of configurations which will seal adequately while
providing an acceptable fit. -
Figure 3 shows an alternate, hut less preferred
embodiment of the invention wherein cut-out 19 is attenuated
or eliminated from the brief. It will be appreciated that
this embodiment will only work if portions of the brief
material transversely outward of elastic member 10 will
gather in response to retraction of elastic members 10 along
elastic retraction lines 13 and will fold when the brief is
worn so that the seal as described for the preferred embodi-
ment of the invention will not be hindered by the presence
of this material. It will further be appreciated that the
general overall shape of the brief may be modified substan-
tially in other ways from the preferred embodiment without
departing from the scope of the invention, which is defined
by the claims. The most preferred values of ~ and ~ for
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this embodiment are about 125 deyrees and about 132 deyrees,respectively when the elastics are located within about
8-1/2 inches of the lateral edge of the crotch portion of
the diaper along a majority of their length. As this
distance is decreased, the included angle (~ - ~) generally
increases.
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