U.S. patent number 3,924,626 [Application Number 05/313,594] was granted by the patent office on 1975-12-09 for rectangular disposable diaper having a contoured absorbent pad.
This patent grant is currently assigned to International Paper Company. Invention is credited to Charles A. Lee, Frank D. Sorrells.
United States Patent |
3,924,626 |
Lee , et al. |
December 9, 1975 |
Rectangular disposable diaper having a contoured absorbent pad
Abstract
A disposable diaper having rectangular dimensions including an
absorbent pad whose central width is less than its end width. The
diaper includes compliant spans of superposed backing sheet and
cover sheet located on each side of the diaper in the crotch region
and adapted to encircle a child's legs and is folded with a
plurality of longitudinal folds along each side thereof, the folds
incorporating the spans.
Inventors: |
Lee; Charles A. (Knoxville,
TN), Sorrells; Frank D. (Knoxville, TN) |
Assignee: |
International Paper Company
(New York, NY)
|
Family
ID: |
23216347 |
Appl.
No.: |
05/313,594 |
Filed: |
December 8, 1972 |
Current U.S.
Class: |
604/366;
604/385.201; 604/378 |
Current CPC
Class: |
A61F
13/515 (20130101); A61F 13/539 (20130101); A61F
13/49426 (20130101); A61F 2013/4512 (20130101); A61F
2013/53908 (20130101); A61F 2013/5395 (20130101); A61F
2013/49076 (20130101); A61F 2013/53445 (20130101); A61F
2013/15886 (20130101); A61F 13/534 (20130101); A61F
2013/5326 (20130101) |
Current International
Class: |
A61F
13/15 (20060101); A61F 013/16 () |
Field of
Search: |
;128/284,286,287,290,296 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Gaudet; Richard A.
Assistant Examiner: Frinks; Ronald L.
Attorney, Agent or Firm: Fitch, Even, Tabin &
Luedeka
Claims
What is claimed is:
1. A disposable diaper comprising in combination,
a liquid impervious backing sheet having rectangular
dimensions,
a liquid pervious cover sheet, substantially coextensive in length
with said backing sheet and at least as wide as said backing sheet,
disposed in superposed relation to said backing sheet and covering
said backing sheet to isolate said backing sheet from the skin of a
person to whom the diaper is applied,
a continuous absorbent pad of generally hour-glass profile having a
midsection and opposite end portions disposed between said backing
sheet and said cover sheet, said pad in its end portions extending
laterally substantially to the side margins of said backing sheet,
whereby said pad at its ends substantially encompasses the waist of
a person to whom the diaper is applied but is more narrow than said
backing sheet, portions of said cover sheet overlying said backing
sheet in the crotch region of said diaper and laterally of said pad
midsection to define a span of diaper that is substantially free of
said pad on each side of said diaper,
continuous bond line means joining said backing sheet to said cover
sheet along lines disposed on opposite sides of said pad
immediately adjacent to and aligned with the respective contours of
said side margins, said lines being substantially coextensive in
length with the longitudinal dimension of said pad and defining a
substantially liquid impervious barrier against lateral migration
of liquid exudate from said pad,
said diaper being folded with a plurality of longitudinal folds
along each side edge thereof, said folds incorporating said spans
therein whereby when said diaper is applied with said narrow
midsection of said pad disposed in the crotch of said person, said
spans at least partially encircle the legs of said person to
securely position said diaper about said legs and maintain said pad
positioned within said crotch.
2. The disposable diaper of claim 1 wherein said cover sheet is
substantially equal in width with said backing sheet and each of
the opposite side edges of said diaper is folded inwardly toward
the longitudinal centerline of said diaper to define a first
longitudinal fold, and folded back upon itself to define a second
longitudinal fold.
3. The disposable diaper of claim 1 wherein said cover sheet is
wider than said backing sheet and side margin portions thereof are
wrapped around the side margins of said backing sheet, and each of
the opposite side edges of said diaper is folded inwardly toward
the longitudinal centerline of said diaper to define a first
longitudinal fold, is folded back upon itself to define a second
longitudinal fold, and further folded inwardly toward said
longitudinal centerline of said diaper to define a third
longitudinal fold overlying said second longitudinal fold, said
cover sheet being sufficiently wider than said backing sheet so
that those portions of said cover sheet wrapped around said side
margins of said backing sheet cover substantially all of the
exposed surface of said third longitudinal fold.
4. The disposable diaper of claim 1 wherein said cover sheet is
bonded in spaced apart locations to said backing sheet in the
regions where there is no portion of said pad interposed
therebetween.
5. The disposable diaper of claim 1 and including an elongated bond
between said backing sheet and said cover sheet extending across
each of the opposite ends of said diaper at locations outwardly
from the opposite ends of said pad and laterally past the opposite
side margins of said pad, said bond means on each side of said pad
intersecting said bond at each opposite end of said diaper to
define a substantially continuous liquid exudate migration barrier
about the periphery of said pad.
Description
This invention relates to a diaper of the type intended to be used
once and discarded. In general, these diapers are referred to in
the art as "disposable diapers."
Disposable diapers have long been known in the art and their
commercial acceptance appears reasonably assured. Of the various
disposable diapers that have been proposed, many have disadvantages
which make them less than completely satisfactory. Accordingly, it
is an object of the present invention to provide a disposable
diaper which is free of certain of the disadvantages present in
prior art diapers of this type. It is a further object of this
invention to provide a disposable diaper having elements of unique
configurations that provide various functional and other advantages
.
Other objects and advantages of the invention will be recognized
from the following description, including the drawings in
which:
FIG. 1 is a representation of an unfolded diaper embodying various
features of the invention;
FIG. 2 is a fragmentary view, partly sectioned, showing a corner of
the diaper depicted in FIG. 1;
FIG. 3 is a sectional view taken generally along the line 3--3 of
FIG. 1;
FIG. 4 is a sectional view of an alternative embodiment of the
disclosed diaper showing an absorbent pad having a constant
thickness across its width;
FIG. 5 is a fragmentary sectional view taken generally along the
line 5--5 of FIG. 1;
FIG. 6 is a fragmentary sectional view taken generally along the
line 6--6 of FIG. 1;
FIG. 7 is a representation of a folded diaper including various of
the features of the invention;
FIG. 8 is a fragmentary sectional view taken generally along the
line 8--8 of FIG. 7;
FIG. 9 is a fragmentary sectional view of an alternative embodiment
of the folded diaper disclosed herein;
FIG. 10 is a fragmentary representation of an absorbent pad
suitable for use in the disclosed diaper;
FIG. 11 is a representation of a diaper embodying various features
of the invention and showing a portion of the folds of the diaper
partly opened.
Briefly stated, the objects of the present invention are
accomplished by means of a disposable diaper having rectangular
dimensions including an absorptive pad having an hour-glass profile
encased between backing and cover sheets. The diaper may be used in
a flat condition, but preferably is folded along its opposite side
edges to provide longitudinal folds that provide advantages which
will be referred to hereinafter.
Referring to the FIGURES, the primary absorbent element of the
disclosed diaper 10 comprises an absorbent pad 12. Contrary to the
rectangular absorbent pads used in certain prior art disposable
diapers, the absorbent pad 12 of the disclosed diaper 10 has an
hour-glass profile including a relatively narrow midsection 14
flanked by wider end sections 16 and 18, each of which includes
lobular portions 20 and 22 that extend laterally of the
longitudinal centerline 21 of the pad and terminate short of the
respective side edges 24 and 26 of a backing sheet 28 (See FIGS. 1,
2 and 3).
The absorbent pad 12 is overlaid on a rectangular liquid impervious
backing sheet 28 such as a plastic film which preferably is
embossed to enhance its appearance and hand. The plastic backing
sheet 28 provides a barrier against liquid flow through the
thickness of the diaper and is disposed on that side of the
absorbent pad 12 which is intended to face away from the child when
the diaper is applied. In the present diaper, the backing sheet 28
is rectangular and of a greater length than the pad 12 so that the
opposite ends 30 and 32 of the pad terminate short of the ends of
the backing sheet (See end 33 in FIG. 2). That side of the backing
sheet opposite the side thereof which is in contact with the
absorbent pad 12 faces outwardly of the diaper when in use to
define an exposed surface 34.
On that side of the absorbent pad 12 opposite the backing sheet 28
there is overlaid a rectangular liquid pervious cover sheet 36.
This cover sheet is intended to contact the skin of the child when
the diaper is applied and to permit fluid exudate from the child to
pass therethrough to be absorbed by the underlying pad. Cover
sheets of synthetic nonwoven materials function satisfactorily to
pass the fluid exudate, aid in preventing escape of fluff fibers,
and simultaneously provide strength to maintain integrity of the
diaper.
The cover sheet 36 of the disclosed diaper is generally coextensive
in length with the backing sheet so that the ends (see end 38) of
the cover sheet overlie the ends of the backing sheet. These
overlying ends are bonded to each other as by bond lines 44 and 45
to close the ends 40 and 42 of the diaper and prevent loss of
absorbent material. In a similar manner, the cover sheet overlying
the backing sheet on opposite sides of the contoured pad is bonded
to the backing sheet as by bond lines 41 and 43 which preferably
follow the contour of the pad restrict movement of the pad relative
to the cover and backing sheet as well as forming barriers that
limit lateral flow of liquid exudate as by wicking. The bonds at
the ends and sides of the pad may be formed by localized
application of heat and pressure or through the use of one or more
seams of adhesive. Continuous lines of water-insoluble adhesive,
such as hot melt adhesive, disposed between the overlying portions
of the cover and backing sheets have been found useful to both
close the ends and sides of the diaper and provide barriers against
transfer of liquid exudate from the pad ends and sides and out of
the diaper as by wicking or other fluid flow mechanism.
In each embodiment of the disclosed diaper, the cover sheet 36 is
at least as wide as the backing sheet 28 so that substantially all
parts of that surface of the plastic backing sheet which face the
child when in use are covered with the relatively soft and pervious
cover sheet. In this manner, the child is protected from contact
with the relatively harsh and abrasive plastic. Isolation of the
child from the plastic backing sheet by means of the interposed
porous and soft cover sheet permits at least limited air
circulation between the diaper and the child's legs, keeping these
areas relatively dry and free of the moisture which tends to
accumulate and cause adverse reactions when the plastic lays flat
against the child's skin for prolonged periods of time and is
adhered thereto by moisture. As shown in FIG. 1, the cover sheet
preferably is bonded as by spot bonds 47 at spaced apart locations
over a major portion of its surface to the underlying pad or to the
underlying plastic backing sheet in those regions where there is no
pad disposed between the cover and backing sheets to assure
continued registry of the diaper components through its period of
use. The preferred bonds 47 are spaced apart by a distance, such as
about 1 - 11/2 inches and the extent of bonding is kept
sufficiently small as will not deleteriously reduce the flexibility
of the backing sheet and cover sheet so that these elements retain
good compliancy. Additional spot bonds 46 may be provided between
the cover sheet 36 and the pad 12 to secure these elements against
movement relative to each other. In the preferred folded diaper,
that portion of the cover sheet overlying and covering the upper
surface of the plastic backing sheet in that fold facing the child
is bonded to the plastic backing to a limited extent, or not bonded
at all, to provide for at least limited relative movement between
the plastic backing sheet and the cover sheet thereby permitting
air circulation into and out of the diaper in the leg and crotch
region.
In one embodiment of the diaper, depicted in FIGS. 2, 3, 4, 6 and
8, the cover sheet 36 is substantially wider than the backing sheet
28 and the side edges 48 and 50 of the cover sheet are wrapped
about the respective side edges 24 and 26 of the backing sheet 28
to terminate at a location spaced inwardly of the diaper toward its
longitudinal centerline. The cover sheet side edges 48 and 50 are
bonded to the exposed surface 34 of the backing sheet as by means
of longitudinal bond seams 52 and 54. In this manner, the cover
sheet is positioned next to the child's skin when the diaper is
folded and applied as described hereinafter. The bond seams 52 and
54 and the bonds 44 and 45 at the opposite ends of the diaper
effectively seal the cover sheet 36 to the backing sheet 28 around
substantially the entire periphery of the cover sheet to assure
that these elements remain in position relative to each other and
assure that the cover sheet overlays the plastic backing sheet in
those portions of the backing sheet which would otherwise be
exposed for contact with the child.
A disposable diaper 10 having a rectangular outline and including a
profiled absorbent pad 12 encapsulated between a liquid impervious
backing sheet 28, having an outer exposed surface 34, and a liquid
pervious cover sheet 36 is depicted schematically in the Figures.
As shown in FIGS. 1, 7 and 8, the disclosed diaper is folded
employing a fold which in cross section resembles the Greek symbol
sigma (.SIGMA.) on one side of the diaper, hence is referred to as
a sigma fold. (It will be recognized that the fold on one side of
the diaper will be a mirror image of the fold on the other side of
the diaper so that one fold will be a "reverse" .SIGMA..) In
accordance with this folding feature, each of the side edges 56 and
58 of the flat diaper, (side edge 56, for example) is folded
inwardly toward the longitudinal centerline of the diaper along a
longitudinal fold line A located inwardly from the respective side
edge 56 of the diaper by about one-third of the diaper width, to
define a first longitudinal fold 60. The side edge 56 of the diaper
is further folded outwardly from the diaper centerline along a
second longitudinal fold line B to define a second longitudinal
fold 62 overlying the first fold 60. Still further, the diaper side
edge 56 is folded inwardly, in the same direction as the first
fold, along a third longitudinal fold line C to define a third
longitudinal fold 64 that overlies the second fold 62. Upon
completion of this third fold on each side of the diaper, the side
edges of the pad 12 and the side edges of the backing sheet 28 are
disposed inwardly toward the centerline of the diaper, but the
cover sheet 36 extends over the top surface 66 of the third fold
64, wraps the pad and backing sheet at the location of the third
longitudinal fold line C, and terminates on the underside 68 of the
second fold 62.
As noted, in cross section, the central unfolded portion 67 of the
diaper and the three folds 60, 62 and 64 on one side of the diaper
resemble the Greek symbol sigma (.SIGMA.), hence is referred to as
a sigma fold (the fold on the opposite side of the diaper resembles
a "reverse" .SIGMA.). This fold, in combination with the relatively
narrow pad midsection 14 permits the diaper to be snugly wrapped
about the child's legs with the pad midsection 14 well within the
child's crotch to retain the exudate within the confines of the
diaper and prevent it from leaking out of the diaper in the leg
regions. Because the plastic backing sheet extends the full width
of the diaper (in the top fold as well as in the other folds), the
exudate is kept from striking through the pad in the crotch region
(i.e., centrally of the diaper) where there is normally a greater
amount of flexing and working of the diaper due to the child's leg
movements. The exudate is thus trapped within the diaper, keeping
the child's outer clothing or bedding more free of leaking exudate.
Such trapping of the exudate is enhanced in the disclosed diaper by
two "V"-shaped troughs 70 and 72 formed on each side of the diaper
by the folds (See FIG. 11). Both troughs, and particularly the
first trough 70, receive and disperse exudate in a direction
longitudinally of the diaper. The second of the troughs 72 further
serves to assure the containment for a time sufficient to permit
absorption of any exudate that moves past the first trough.
The folds on each side of the diaper are secured in their folded
position at points located approximately on the transverse
centerline of the diaper, preferably by tack bonds 74 and 76. This
is accomplished by placing a small spot of adhesive between
selected folds as the folds are being formed. Hot melt adhesive of
the ethylene vinyl acetate type available commercially as No.
34-2938, from National Starch Company, serves satisfactorily for
this purpose. This adhesive is not water soluble so that it does
not dissolve in the presence of fluid exudate, but rather the spot
bonds cause the diaper to retain its folded condition in the crotch
region throughout its period of use. This same adhesive suitably
serves for making the bond lines 44 and 45 at the ends of the pad
and the bond lines 41 and 43 at the edges of the pad.
In the depicted diaper, tack bonds 74 and 76 are provided in the
folds on each side of the diaper between the underside 78 of the
first fold 60 and the central portion 67 of the diaper, and between
the underside 80 of the top (third) fold 64 and the upperside 81 of
the second fold 62. When the diaper is applied to the child, these
tack bonds keep these folds together to insure good fit of the
diaper in the crotch region but permit the first and second folds
to separate and provide expansion of the diaper to conform to the
child's legs. In a preferred tack bond, the facing portions of the
cover sheet in the folds are joined so that when the diaper is
applied to the child, the cover sheet unfolds to a lesser extent
than the absorbent pad and effectively reduces the width of the
diaper in the crotch region to provide a better fit on the
child.
An alternative manner for folding the diaper is shown in FIG. 9. In
this alternative, each of the diaper side edges is formed into a
wing fold by bringing the longitudinal side edge portion (only side
edge 56' is shown) of the diaper inwardly toward the centerline of
the diaper. This folded side edge portion extends inwardly of the
diaper a distance less than about one-third the width of the diaper
to form a first longitudinal fold 86 along the side of the diaper.
As thus folded, the longitudinal side edge of the diaper overlies
the longitudinal central portion 87 of the diaper and extends the
length of the diaper. The first fold 86 is next folded back upon
itself to form a second fold 88 extending along the length of the
diaper and overlying the first fold 86, thereby providing two
longitudinal folds 86 and 88 (FIG. 9) in each wing fold, overlying
the marginal edges of a central portion 87 of the diaper. As
depicted, the first fold 86 is secured to the underlying center
portion as by a spot bond 90 to cause the folded diaper to retain
its folded form at least while the diaper is being secured to the
child's body thereby insuring that the accumulated configuration of
the central portion of the diaper comfortably and snugly resides
within the child's crotch and in position to efficiently receive
body exudate. The spot bond 90 preferably is located generally
centrally of the fold, i.e., medially of both the longitudinal and
transverse dimensions of each fold. Spots of hot melt adhesive
suitably hold the folds 86 and 88 in place.
It will be recognized that the diaper is applied to a child in the
usual manner, that is, by fanning out one end 82 of the diaper,
laying the child on the opened end and bringing the opposite end 84
of the diaper up between the child's legs. This opposite end 84 is
also fanned out and the corners of the two ends joined to fasten
the diaper about the child's waist. In this operation, the folds
remain closed (folded) in the immediate region of the transverse
centerline of the diaper but gradually increasingly expand in the
direction away from the transverse centerline toward the ends of
the diaper. In the present diaper the layers of backing sheet and
cover sheet in each of the three folds on each side of the diaper
are maintained in their relative positions within each fold and can
be pulled tight about the child's legs thereby imparting excellent
conformability of the diaper to the child in the leg region, hence
a better fit on the child. This feature is due also in part to the
number of folds which increase the expansibility of the diaper in a
direction generally perpendicularly to the diaper proper, so that
as the ends of the diaper are fanned open, such action does not
place such stresses on the diaper in the crotch region as cause it
to buckle and fall away from a good fit about a child's legs.
In the disclosed diaper, adhesive strips 92 and 94 are provided on
opposite corners 96 and 98 of one end 84 of the diaper with a
portion of each strip projecting from the side edge of each corner.
When the two ends of the diaper are in place about the child's
waist, these strips provide a means for releasably joining the
diaper ends together to secure it in position on the child in a
manner well known heretofore.
In accordance with one embodiment of the present invention, the
contoured pad (e.g., having an hour-glass profile) is generally
centered on the rectangular backing sheet with the more narrow
midsection 14 of the pad generally aligned with the transverse
centerline of the backing sheet. In this position, the pad ends 30
and 32, including the lobular portions 20, 20' and 22, 22' on each
end extend across respective ends of the diaper to provide
substantial absorbent material in those parts of the diaper which
encircle the child's waist when the diaper is in use. The diaper is
thus fully padded around the child's waist to avoid the discomfort
of the ledges found in the diapers having rectangular pads that are
substantially more narrow than those elements which hold the pad in
place on the child. Importantly, the absorptive capacity added to
the diaper ends by the lobular portions 20, 20' and 22, 22' aids in
preventing the escape of fluid exudate from the diaper ends as when
a child is in a prone position and the exudate tends to migrate to
the diaper ends.
While providing the advantages of a full width pad in the ends of
the diaper, the disclosed diaper provides a good fit on the child,
especially in the crotch region. This is due to the pad profile
which is chosen to provide reduced width of the absorbent pad in
the crotch region so that the diaper enters the crotch well without
excessive bulkiness. In the present diaper, the pad is flanked in
the crotch region by substantial spans 100 and 102 (FIG. 1) of
backing sheet overlaid by the cover sheet and which do not include
pad therebetween so that they are thin and flexible. As described
hereinbefore, the diaper is folded with longitudinal folds. The
spans 100 and 102 are disposed within such folds so that the
compliant folded spans fit snugly about the girth of the child's
legs to securely retain the pad midsection 14 in position within
the crotch. Importantly, the spans 100 and 102 include portions of
the water-impervious backing sheet so that in combination with the
pad midsection, the spans aid in forming a pocket in the child's
crotch which receives both liquid and solid exudate. The pocket
functions to ensure retention of the liquid exudate within the
confines of the diaper for a time sufficient for its absorption by
the pad. Moreover, the pocket functions to retain solid exudate and
reduce the likelihood of its escape from the diaper in the leg
regions. Retention of the cover and backing sheets in their
superposed position is assured by the spot bonds 47 referred to
hereinbefore.
As noted hereinbefore, that portion of the cover sheet 36 overlying
and covering the plastic backing sheet 28 in the top fold 64 of the
diaper is provided with at least limited freedom of movement with
respect to the underlying portion of the plastic backing sheet so
that these elements are free to work relative to each other when
the diaper is applied to a child and the child moves his legs. In
this manner, air circulation into and out of the diaper in the
crotch region is enhanced. Further, this relative freedom of
movement permits the cover sheet to slide to at least a limited
extent relative to the plastic thereby preventing the diaper from
binding against the child's legs which develops undue stresses in
the diaper and discomfort to the child.
Referring particularly to FIG. 10, one suitable absorbent pad 12
comprises defiberized wood fibers, i.e., pulp, referred to in the
art as fluff 104. In a common method of manufacturing the pad, the
fluff 104 is deposited on a tissue web or sheet 106 which is of
substantially the same width as the fluff and thereafter overlaid
with a second tissue 108 of equal width with the fluff to sandwich
the fluff between the two sheets of tissue. For purposes of the
present discussion, the term "absorbent pad" is intended to include
this embodiment as well as other variations and combinations of
absorptive materials suitable for use in disposable diapers. One
such other material comprises multiple plies of creped wadding die
cut or otherwise contoured as disclosed herein. One system for the
manufacture of contoured pads using air laying techniques is
disclosed in pending application Ser. No. 174,092 filed Aug. 23,
1971, now U.S. Pat. No. 3,717,905.
As desired, the fluff may be formed with a constant thickness as
depicted in FIG. 4. A pad having additional thickness of fluff in
the region of its longitudinal center provides additional
absorptive capacity in such longitudinal center region of the
diaper and is preferred because such pads aid in keeping liquid
exudate within the central portions of the diaper, thereby
minimizing leakage. Such a pad is depicted in FIGS. 1, 3 and 6.
Films of various plastics provide acceptable liquid impervious
backing sheets. Polyethylene film, embossed with a taffeta pattern,
is particularly suitable because of its appearance and availability
at low cost. Films of about one mil thickness provide sufficient
strength when combined with a suitable cover sheet to provide
integrity to the diaper. Such relatively thin films more closely
resemble a cloth material so that the diaper is pleasing in
appearance and feel. These thinner films also are flexible to the
extent that the diaper is permitted to conform to the contour of
the child's body and provide a good fit on the child. Films having
a thickness of greater than about 3 mils are excessively harsh,
displeasing in appearance and more expensive so that their use in
the present diaper is not desired.
One particularly suitable nonwoven material for the cover sheet 36
comprises a web formed from synthetic, hydrophobic fibers, such as
rayon fibers alone or mixed with wood fibers, that have been
stabilized in web form as by an adhesive which bonds adjacent
fibers one to another. Fiber lengths of about one-half inch formed
into a web about 5 mils thickness provide sufficient interfiber
bonding to develop good tensile strength in the web so that when
the web is incorporated, with a plastic backing sheet, into a
disposable diaper, the diaper resists tearing or other destructive
forces such as are present when the diaper is applied to an active
child. Nonwoven material comprising rayon fibers and known as
Dryfil 300-205 and available from Nonwoven Products Division of
International Paper Company, New York, N.Y. has been successfully
used as the cover sheet in a disposable diaper having a 1-mil thick
polyethylene backing sheet. In webs about 5 mils thick and weighing
about 0.624 ounces per square yard, this nonwoven material
possesses a toughness such that adjacent folds of the cover sheet
can be tacked to each other so that the diaper remains in its
folded condition when in use as referred to hereinafter.
Spunbonded, continuous, nylon filaments stabilized in web form and
available from Monsanto Company, St. Louis, Mo. under the trademark
Cerex, also provide a suitable cover sheet material.
In one embodiment of the disclosed diaper intended for "daytime"
use on children weighing approximately 22 pounds, the diaper
measures about 14 inches in width and 18 inches in length. The pad
in such diaper is about 15 inches long, about 121/2 inches wide at
its widest points, and about 5 inches wide in its midsection. These
dimensions provide a diaper wherein each of the side edges of the
diaper will adequately encircle a child's leg having a girth of up
to about 15 inches. It will be recognized that various dimensions
and combinations of dimensions of the diaper elements are suitable
depending on the size of the person for which the diaper is
intended. In this diaper, the absorbent pad includes about 39 grams
of fluff and about 6 grams of tissue web disposed on opposite sides
of the fluff.
Diapers for incontinent adults obviously are larger than diapers
for newborn babies. In any event, the width of the more narrow
midsection of the pad element of the diaper is chosen to be
sufficiently narrow as permits the diaper to readily fit within the
child's crotch without excessive bulkiness. This width is in part
limited by the absorptive capacity and rate of the diaper (the
fluff and cover sheet) but when using a dry-laid nonwoven cover
sheet and wood fiber fluff, the pad midsection is at least about 4
inches in width to accommodate the anticipated exudate discharge
without leakage. In any event, the width of the absorbent pad at
its midsection is not greater than the width of the central
longitudinal unfolded portion 67 of the diaper plus the widths of
the first folds 60 and 60' on opposite sides of such unfolded
portion 67, thereby assuring that the pad midsection does not
extend laterally into more than the first folds of the diaper.
Preferably, the pad, at its most narrow width, is no wider than the
width of the unfolded portion 67.
The width of the pad at its ends preferably results in the pad
extending fully around the child's waist when the diaper is
applied. This is normally accomplished by providing a pad that is
not less than about 11/2 inches more narrow at its ends than the
backing sheet so that when the diaper ends are pinned, the pad
corners slightly overlap. The transition in pad width from its ends
toward its narrow midsection may be continuously curving or more
abruptly changing as desired.
The rectangular configuration of the disclosed diaper affords
advantages in manufacture in that it is more readily and
economically made than is a nonrectangular diaper. Particularly, it
is less costly to fold the present rectangular diaper. More
importantly, however, the rectangular configuration, in combination
with the contoured pad, provides diaper portions in the crotch
region for distributing exudate within the diaper and for retaining
exudate inside the diaper for a time sufficient to ensure
absorption of the exudate by the pad. Such diaper portions in the
crotch region also serve to circumscribe the child's legs and
securely position the more narrow pad portion well within the
child's crotch without the pad itself being required to possess
sufficient strength and integrity to maintain its position in the
crotch. The good wrap of the diaper about the child's legs provides
a good-fitting diaper which functions well in retaining exudate and
inspires confidence in the diaper by the mother.
While a preferred embodiment has been shown and described, it will
be understood that there is no intent to limit the invention by
such disclosure, but rather, it is intended to cover all
modifications and alternate constructions falling within the spirit
and scope of the invention as defined in the appended claims.
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