Note: Descriptions are shown in the official language in which they were submitted.
~L00706
JBP 100
The present invention relates to shaped absorbent
pads for use in disposable diapers~
Disposable diapers have and are continuing to
gain wide acceptance as a substitute for previously used
cloth diapers and as an adjunct to such cloth diapers. Most
disposable diapers have been rectangular in shape and folded
in a manner to aid in their application about the buttocks of
the baby. In some instances, the diapers have been folded
in geometric configura~ions to aid in their application
to the baby. Also, some diapers contain hourglass shaped
absorbent panels; that is, absorbent panels which are
narrow in the center portion and wide at the front and
rear end portions. :~
It has been known for some time now that if the
bulk of the diaper could be reduced in the area between
the legs of the wearer the fit of the diaper would be
improved. However, reducing ~he bulk in the area between
the legs means reducing the amount of absorbent material
used in that area, an area where absorbency is very important. ~ :
What I haYe ~iscovered is a new and improved
shaped absorbent pad for use in disposable diapers. My
new and improved shaped pad reduces the bulk between the
baby's legs while maintaining excellent absorptive
efficiency of the pad both in the front portion and the
-2-
ll~)V7V6
JBP 100
rear portion of the pad. IFurthermore, my lmproved pad
provides an excellent fit about the baby's legs them-
selves to produce an aesthetically appealing diaper and
a more stable diaper during use.
SUMMARY OF THE PRESENT ~NVEMTION
_ _ .
The improved pad of the present in~ention is
substantially rectangular in shape. The pad has a pair of
short parallel ends and a pair of long parallel sides
perpendicular to said ends. Disposed in opposed relation-
ship on each longit~dinal side is an indentation. The
deepest point of each indentation is positioned at
approximately one-third the length of the rectangular
panel to divide the pad into a short portion to be
positioned in front of the ba~y and a longer rear portion
to extend between the baby's legs and behind the buttocks.
The front edge of each indentation is arcuate and the
front half of each indentation has substantially the shape
of a quadrant of a circle. The rear edge of each indenta-
tion has a uniformly straight slope from the deepest part
of the indentation to the longitudinal side of the pad
at an angle ~f from ahout 30 to 45 degrees to the center
of the sides o~ the pad, The rear half of each
indentation has a substantially triangular shape~
11L)0706
JBP 100
By virtue o~ the above-described shape, maximum
absorpt~e capacity of the pad is retained in the crotch
region; while at the same time improYed fit around the
legs of the baby is provided.
In a preferred embodiment of the pad of the
present invention, the four corners have extended portions
to provide the pad with extra absorbent capacity. In
another embodiment of my ~mpro~ed pad, the cross-sectional
shape of the pad is contoured with the center portion
Of the pad being thicker than the edge portions of the
pad to provide extra absorbency in the central area.
The improved pad of the present invention
is usually used between a pervious or permeable facing
layer which is soft and is disposed against the baby's ~
skin and may be of such material as to ma~ntain the ~ -
baby's skin relati~ely dry while the diaper is being worn
and a backing layer on the opposite side of the pad from
the facing layer. The backing layer is generally an
imper~ious film material to prevent strike-through of
liquid. In sQme embodiments, my improved pad may contain
a densified paper-like skin area and one or more densified
compacted geometrical areas to improve the wicking,
capillarity and distribution of liquid through the
absorbent pad and impro~e its efficiency. ~~~~~~~
706
According to a broad aspect of the present inven-
tion there is provided a multi-layer diaper comprising a
porous facing layer, an absorbent pad positioned in face~to
face juxtaposition with the facing layer. -!The side edges of
the pad terminate inwardly from the side edges of the facing
layer, and a water-impervious bac]~ing sheet is positioned in
face-to-face juxtaposition with the pad on the surface of
the pad, opposite from the facing layer. The backing sheet
i5 generally coextensive with the facing layer. The facing
layer and the backing sheet are adhered to one another in
marginal areas beyond the pad. The pad is substantially
rectangular in shape and has an indentation along each
longer parallel side, The indentations are disposed opposite
each other and are positioned approximately one-third the
distance from one end of the pad, to define a shorter front
portion and a longer rear portion of the pad, where~y a
diaper having an improved fit is produced. The sides of the
pad immediately adjacent the indentations in the central
portion of the pad is parallel with the longitudinal center
line of the pad whereby the improved fit is obtained with
minimum loss of absorptive capacity.
- 4a -
~007a6
JBP 100
BRIEF DESCRIPTION OF THE DRAWIN~S
The invention will be more fully described in
conjunction with the accompanying drawings where;n:
FIGURE 1 is a plan view of the improved pad of
the present invention;
FIGURE 2 is a plan view of a disposable diaper
incorporating the improved pad of the présent
invention with a portion broken away to show the various ,~
layers;
FIGURE 3 is a plan ~iew of another embodiment
of a disposable diaper incorporating the improved pad
of the present invention;
FIGURE 4 is a plan view of another embodiment
of a disposable diaper incorporating the improved pad
of the present invention with a portion broken away to
show the various layers;
~IGURE 5 is another em~odiment of a disposable
diaper incorporating the pad o the present in~ention
with portions broXen away to show the various layers;
FIGURE 6 is a cross-sectional view along line
6-6 of Figure 4;
FIGURE 7 is an enlarged cross-sectional view
of a portion of an embadiment of the improved pad of the
present invention;
11007V6
JBP 100
FIGURE 8 is another corss-sectional view of
another embodiment of the pad of the present invention.
DETAILED DESCRIPTION OF THE DRAWINGS
As shown in Figure 1, the absorbent pad of the
present invention has a substantially rectangular shape.
The pad has parallel opposite end margins ll and 12 and
parallel opposite longitudinal side margins 13 and 14.
Along ~he longitudinal margins there are disposed
indentations 15 and 16. The deepest part of the
indentations is approximately One-third along the length of
the pad to form a smaller ~ront portion 17 and a larger
rear portion 18. The front edge 19 o~ each indentation
is arcuate and the front half of the indentation has the
shape of a ~uadrant of a circle. In use, the fxont edge
contacts the inner and front portion of the baby's leg
or ~high to pro~ide a good fit in that area. The rear
edge 20 of the indentation is generally uniformly sloped
from the deepest part o~ the indentation to the longitudinal
edge portion. In use, this rear edge fits about the
rear of the baby's leg or thigh to provide a good fit
~20 in that area. The sloped rear edge makes an angle of about
30 to 45 degrees to the ~enter line of the ~iaper. The
side margins adjacent the indentations in the central
1101)706
JBP 100
portion of the pad are parallel with one another. This
con~iguration provides the improved fit with a minimum
loss of absorptive capacity. As shown in this Figure 1,
the four corners 21, 22, 23, and 24 contain extended
longitudinal side portions which fit about the waist area
of the wearer and proYide increased absorbent material
and capacity in the pad. ~he size and shape of the corners
may vary greatly depending on the type and size of the
diaper being produced.
The indentations, depending on whether the
diaper is a newborn size, toddler size, or other size,
will vary from about an inch to two inches in depth and
preferably from about 1 1/4 to 1 3/4 inches in depth. The
front edge or quarter circle is on a radius similar to
the depth or equal to the depth dImension. The distance
the daepest part of the indentation may be from the front
end margin of the absorbent pad may vary from about four to
six inches and from about 30~ to 40% of the total length
of the pad and preferably from about 30% to 35% of the
. .
total length of the pad to provide the desired fit and
aesthetically shaped pad. In some embodiments o the
indentation, the portion of the front edge which meets
the longitudinal side of the pad may be a straight portion;
i.e., perpendicular to the side, depending on the size
of the diaper being produced. The gently sloped rear edge,
_z_
1100706
JBP 100
where it starts from the deepest part of the indentation,
may also be gently rounded be~ore it straights out to its
desired slope, again depending on the size of the diaper
being produced. The indentation as described provides a
close, neat fit around the wide variety of leg sizes.
The narrowed crotch area; i. e., the dimension
of the pad between indentations, may also be varied
according to diaper size. This dimension may be as small
as 3 to 3 1/2 inches for a newborn size diaper or as
large as 4 1/2 inches or more for toddler or other large
size diapers. I have found a narrowed crotch area
dimension of 3 1/2 to 4 inches to be satisfactory for
most size diapers.
In Figure 2, there is shown a diaper 27
comprising an impervious backing sheet 28, shaped
absorbent pad 29, and a pervious or permeable facing
sheet 30. At one end of the diaper along both -
longitudinal side margins are a pair o~ adhesive tape
tabs 31 for affixing the diaper about the infant. The pad
29 has two parallel end margins and two parallel longitudinal
side margins. Disposed along each longitudinal side
portion is an indentation 32 with the indentations opposite
each other. The indentations ha~e a quarter circle front
portion and a uniformly sloped back portion and ar~
110(~706
~BP 100
po~itioned approximately one-third of the distance along
the length of the pad.
In the emb~diment in Figure 3~ there is shown
a diaper 33 ha~ing backing sheet 34, a per~ious facing
sheet 35 and a substantially rectan~ular absorbent pad 36.
At the one end of the diaper, are a pair of tape tabs 37
for affixing the diaper about the infant. The pad shown
in this ~mbodiment includes four outwardly extending
corners 38. These corners provide extra absorbent
material to increase the capacity of the pad.
Referring to Figure 4, there is shown
another embodiment of a disposable diaper 40 incorporating
the newly shaped pad of the present invention. The
diaper comprises a shaped impervious film backing member 41
and a co-extensive shaped pervious facing member 42
with a shaped pad 43 of the present invention disposed
therebetween. At one end of the diaper are a pair of
oppositely disposed tape ta~ 44 for affixing the diaper
about the baby. The shaped pad has a pair of oppositely
disposed shaped indentations 45 and 46 along the longitudinal
side edges of the pad. As seen, the shaped indentations
haye a quarter circle front portion and a gently sloped
rear edge. The longitudinal edges 47 and 48 of the facing
and backlng layers are ~ndented to provide the diaper with
_g_
11~(970~i
JBP 100
an overall shape.
As seen in the cross-sectional view shown
in Figure 6, the facing 42 and backing 41 layers
are sealed together along their longitudinai edges 47
and 48 and the absorbent pad includes a wicking
layer, or dense area 49 at the surface next to the ~acking
layer and a plurality of densified or compa~ted longitudinal
lines 50 to aid in.the wic~ing and distribution of fluid
being absorbed by the pad.
As may be more clearly seen in the enlarged cross-
sectional view of Figure 7, the absorbent pad. 51, in many
embodiments of the present in~ention, may have a densified
surface 52 preferably the surface which is d~sposed
adjacent the Lmpervious backing member. This densified
~ 15 paper-like surface may be formed by applying moisture
: to the pad and applying pressure as disclosed in U.S.
Patent 3,017,304 or U.S. Patent 3,993,820. The later
patent includes the addition of longitudinally densified
lines 53 to provide for improved capillarity, wicking :
and distribution of liquids absorbed by the pad.
Referring to Figures 5 and 8, there is shown
another embodiment of a disposable diaper 53 which
incorporates the newly shaped pad 54 of the present invention.
In this embodiment the backing layer 55 is shaped as des-
cribed in conjunction with Figure 4 and the co-extensive
)V706
JBP lO0
.
facing layer 56 is similarly shaped An end portion of
the diaper contains oppositely disposed adhesive tabs
57 for affixing the diaper to the baby. The shaped
pad of the present in~ention is disposed between the
backing and facing layers and contain the indentations 58
disposed approximately one-third along the length of the
pad. Along the longitudinal side edges of the pad
are rubber stxips 59 which are inserted in the diaper
~ in their extended or stretched state, sealed to the
:~ lO backing and/or facing layer and allowed to relax to
.: provide elastic sides in the diaper to provide a tight fit
:: about the baby's legs.
The absorbent pads of the present invention
are preferably formed of loosely compacted, short
cellulose fibers, such as wood pulp fibers, or cotton
: linters, or mixtures thereof, which are primarly held
: together by interfiber bonds requiring no added adhesive,
as is known in the art.
The term "short fibers" as used herein, refers~ 20 ~o fibers less than about 1/4 inch in length, in contrast
to "long fibers" or "textile length fiber " which are
longer than about l/4 inch in length, and generally are
between l/2 inch and 2 l/2 inches in length.
The backing layers used in making the disposable
diapers of the present invention may be any of the thermo-
-lI-
11~()7()6
JBP 100
plastic films such as polyethlene, polypropylene and
the li~e and may contain perforations or breathin~ areas
as desired if these areas are placed in such a manner
as not to allow liquid to pass throuqh.
The facing layers may be any ~f the facing
layers presently used on disposable diapers including the
facing layers described and disclosed in conjunction
with Mesek, et al. U.S. Patents 3,777,758
and 3,768,480 or other non-woven fabrics. Other facing
layers that may be also used in the diapers of the present
invention are the polyester fabrics or the perfora~ed film
materials.
The foregoing description and the drawings
are intended as illustrative and are not to be taken as
limiting. Still other variations are possible without
departure from the spirit and scope of this invention.
-12-
