Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~2~
--1--
DOUBLE FASTENING SYSTEM_WITH A ~LIT
The present invention refers to a fastening system and
more precisely to a double fastening system with a slit
for disposable articles such as disposable diapers.
Backqround of the Invention
Conventional prior art is mainly based on the use of
adhesive tapes for closing or fastening diapers,
especially disposable diapers, around the waist of the
wearer. In addition, the prior art has provided sealing
systems to prevent fluid from leaking from the diaper in
the regions around the wearer's thighs and waist. Sealing
systems which help prevent leakage in the thigh regions
comprise elastic elements, such as elastic bands or one or
more elastic strands, which are secured in the generally
central portions of the side margins of the diaper.
Sealin~ systems which help prevent leakage of liquid at
the waist of the wearer comprise elastic elements which
are secured in the upper and/or lower margins of the
diaper to provide a so-called "elasticized waistband"
diaper. In the prior art, the aforementioned astening or
closure system and the aforementioned sealing system are
interdependent and allowed, relative motion between the
wearer's body and the diaper itself. This produced
bagginess which in turn led to leakage of liquid
especially at the leg regions of the diaper.
The present invention is directed to providing a closure
system which allows a better fitting of such article to
the user, thus reducing ri6ks of leakage by combining such
closure system and elastic system.
JBD-109
- ~.?~
-- 2
S _ ary of the Invention
One object of the present invention is to interrupt
the force-transmitting continuous surface which occurs
in one-adhesive-region systems, by providing a cut
at such adhesive region, which allows the xesulting
two adhesive regions to work independently from
another one.
Another objec-t is to provide a be-tter fi-t-ting of a
diaper around the thighs and waist regions, which
vary with the user's ergonomic characteristics, thus
allowing the legs to move without also moving -the
diaper relative to the body.
_. .
~; Another advantage is the additional option for closing
~;, and fitting such article to the body, each of the
~, aforesaid adhesive regions being adapted to be used
, independently from the other.
;. .
In accordance with the present invention there is
provided a closure system for a disposable article
such as a disposable diaper, said closure system
comprlsing two adhesive regions, symmetrically opposite
with relation to the longitudinal axis of the article
and applied on the outer corners of the liquid permeable
covering of the article, said regions being separated
by a slit which is generally parallel to the transverse
axis of the article or which ex-tends inwardly from
the side margin of the diaper toward a generally
central region thereof.
According to a fur-ther broad aspect o~ the present
invention there is provided a disposable diaper which
30 comprises a liquid impermeable backing sheet and
a liquid permeable covering sheet. The covering
sheet has a surface which contacts the body of the
28~
-2a-
wearer when the disposable article is in use. An
absorbent core is disposed between the backing sheet
and the covering sheet. The diaper has an upper edge
with an upper marginal portion adjacent the upper
edge. A lower marginal portion is also provided
adjacent the lower edge. A pair of side edges are
also provided and each having a side marginal portion
adjacent -thereto. A transverse axis 1les be-tween
the upper edge and the lower edge and the longitudinal
axis lies between the side edges. The transverse
and lonyitudinal axes are mutually perpendicular
and intersect in a central reg;on of -the disposable
article. A first upper corner is provided in the
region where the upper edge meets a first of the
side edges. A second upper corner is provided in
the region where the upper edge meets the second
of the side edges. The backing sheet is secured
to the covering sheet in the marginal portions.
A first area of pressure sensitive adhesive i-s-
applied to the liquid permeable covering sheet
at the first upper corner. A second area of pressure
sensitive adhesive is applied to the li~uid permeable
covering sheet at the second upper corner. A third
area of pressure sensitive adhesive is applied to
S a first of the side marginal portions and spaced
a distance upwardly from the lower edge toward the
transverse axis. A fourth area of pressuxe sensitive
adhesive is applied to the other of -the side marglnal
portions and spaced a distance upwardly Erom -the
lower edge toward the -transverse axis. All of the
areas oE pressure sensitive adheslve are applied
to the body-con-tactiny surface of the liquid permeable
covering sheet. A pair of slits are also provi.ded
and the first of these extends inwardly of the diaper
and toward the transverse axis Erom a point on a
first of the side edges which lies between the third
area of pressure sensitive adhesive and the point
.a~
3`2~
-2b-
of juncture of the fi.rstside edge of the lower edge.
The second of the slits extends lnwardly of the
diaper and toward the tranverse axis from a point
on the other side edges which lies between the four~h
area of pressure sensitive adhesive and the poin-t
of juncture of -the other side edge and the lower
edge.
Brief Description of -the Drawings
The invention can be better understood with reference
to the following detailed description toge-ther with
the appended drawings in which:
.~
~z~
--3--
Fig. 1 is a perspective view of a diaper provided with the
closure system of the present invention.
Fig. 2 is a perspective view illustra~iny another
embodiment of said closure system.
Fig. 3 is a front plan view of the diaper illustrated in
Fig. 1.
Fig. 4 is a 6cheme of actuating forces in the system of
the present invention.
Fig. 5 is a front plan view, with a portion cut away, of
another embodiment of a diaper in accordance with the
- 15 present invention.
Fig. 6 is a perspective view of the diaper of Fig. 5 in a
closed configuration.
Detailed Description of the Invention
Referring now to the drawings, there is shown a diaper 10
having a liquid-impermeable backing sheet 11, a
liquid-permeable facing sheet or covering 12 and an
absorbent core 22 disposed between said backing sheet and
said covering. The diaper further comprises an elastic
element 13 in the central portion of each of the side
margins of the diaper and an elastic element 1~ in the
central reyion of the top margin of the diaper. Backing
sheet 11 may comprise a film of polyethylene or other
liquid-impermeable material. Covering 12 may be a
nonwoven fabric, highly porous paper or similar material
which permits passage of liquid therethrough ~o the
underlying absorbent core. The absorbent core 22 may
comprise, ~.g. comminuted wood pulp or other material
JBD-109
~2~ 6
--4--
having good liquid absorbency. ~lastic elements 13 and 14
may be elastic monofilaments or a tape of hea~ shrinkable
material which, after heat shrinking, has elastic
properties. In the embodiment under discussion, elastic
element 1~ is preferably in the form of an elastic
monofilament which, as seen in Fig. 3, is secured while in
a stretched state between backing sheet 11 and covering
12. When subsequently relaxed, elastic element 14 serves
to gather the material along the upper margin of the
diaper as shown in Figs. 1 and 2. Ela~tic elements 13, 13
at the opposed side margins of the diaper are preferably
in the form of a tape of heat shrinkable material which,
after application of heat thereto, displays elastic
properties. Suitably sized lengths of the heat shrinkable
material are secured in the side margins of diaper 10
between backing sheet 11 and cover 12 as shown in Fig. 3.
The side margins of the diaper are subsequently heated as
a result of which the tapes of heat shrinkable material
shrink to provide the gathered side margins, shown in
Figs. 1 and 2, which encircle the thighs of the wearer
during use. Since, as mentioned above, the tapes have
elastic properties after their heat treatment, the
gathered portions in the side margins of the diaper are
extensible so as to fit comfortably around the thigh
regions of the wearer and provide a gasketing effect to
prevent the leakage of fluid.
It will be recognized that elastic element lg may compcise
two or more elastic monofilaments rather than the single
strand illustrated in the drawings. Alternatively, pieces
of the aforementioned heat shrinkable tape material could
be used as elastic element lg in the upper margin of the
diaper. Similarly, the heat shrinkable tapes comprising
elastic elements 13, 13 at the side margins of the diaper
could be replaced by one or more elastic monofilaments.
JBD-109
~2~3~2~
--5--
While in diaper 10 illustrated in the drawings. absorbent
core 22 is smaller in size than the backing and facing
sheets, it will be understood that core 22 can assume
VariGUS sizes and shapes. Absorbent core 22 can be
stabilized, e.g. by embossing along lines 23, as shown in
Fig. 3. It will be understood by those skilled in the art
that in diaper 10 illustrated in the drawings, backing
sheet 11 and facing sheet 12 may be secured to each other,
e.g. with a suitable adhesive or by heating sealing, at
the marginal portion6 of the diaper. When the backing and
facing sheets are joined around the margins of the diaper
in the fashion just mentioned, the absorben~ core is
prevented from moving; however, the absorbent core may be
further secured against undesirable movement by giving it
~o the underlying backing sheet.
Two distinctive adhesive regions 15 and 16 are provided on
the inner surface ~i.e. that surface which faces the
reader in Fig. 3 and which contacts the body of the wearer
when the diaper is in use) of liquid-permeable covering
12, at each of the upper corners of the diaper, generally
adjacent the ends of elastic element 1~. As can be seen
in Fig. 3, adhesive regions 15, 16 are placed
symmetrically with respect to the longitudinal axis, Y-Y,
of diaper 10 near the upper corners of the diaper.
The adhesive used for regions 15 and 16 may be of the
pressure sensitive acrylic type or any other type
well-known in the art. Preferably, the adhe6ive i6 of the
type which can be readily released erOm the outer surface
of ~acking sheet 11 without undue damage to the backing
sheet or the adhesive. When this type of adhesive is
used, it i~ an easy matter to release the adhesive coated
portions of the diaper from engagement with the backing
sheet when it is desired to adjust the fit of diaper or
JBD-109
--6--
remove it from the wearer. If the adhesive used for
regions 15, 16 i~ not readily releasable from ths outer
surface of the backing sheet, then those portions of the
backing sheet which will normally be contacted by the
adhesive portions may be suitably treated, by methods
known to those skilled in the art, to provide the
necessary easy~release characteristics. The adhesive
ultimately chosen for use may be applied in any convenient
manner, e.g. by an adhesive transfer process.
The preferred embodiment illustrated in Fig. 3 comprises a
pair of geneeally rectangular first adhesive regions 15,
there being one such adhesive region at each upper corner
of the diaper. Thus, each of first adhesive regions 15 i~
located in the upper margin of the diaper adjacent upper
edge 25 and adjacent one of the opposed side edges of the
diaper. Diaper 10 further comprises a pair of generally
rectangular second adhesive regions 16, each of which is
spaced downwardly from upper edge 25 of the diaper and
from its associated first adhesive region 15. Each such
second adhesive area 16 is located, as can be seen in Fig.
3, adjacent one of the side edges of the diaper.
- Adhesive regions 15 and 16 at each side of the diaper are
Z5 separated by a slit 17 running from a side edge of the
diaper toward the central region thereof and generally
parallel to the transverse axis, X-X, of ~he diaper.
In the preferred embodiment, each slit 17 extends farther
inwardly from its respective side edge than do its
associated adhesive regions 15, 16. Each slit 17
terminates at its interiorly located end in a circular
cutout 1~ which helps prevent undesirable tearing of the
diaper by distributing forces applied thereto along such
circular surface. As illustrated in Fig. 3, there is an
JBD-10~
G
--7--
adhesive free region between slit 17 and the lower edge of
the first adhesive region 15 and an adhesive free region
between slit 17 and the upper edge of second adhesive
region 16.
In use, a child to be diapered is positioned facing
upwardly on top of the diaper in the generally flat
configuration shown in Fig. 3 so that the child's buttocks
are disposed more or less centrally of the diaper. The
lower part of the diaper is brought up between the child's
leg so that lower edge 26 is in alignment with upper edge
25. Adhesive areas 15, 15 at upper edge 25 are adhered to
the backing sheet at the corner regions where side edges
27 and 28 meet lower edge 26 (arrow A in Fig. 1). This
action fixes the diaper in position around the child's
waist. Adhesive regions 16, 16 at each side of the diaper
are manipulated to conform the diaper around the thighs of
the child and are then secured to the impermeable backing
sheet 18 (arrow B in Fig. 1). The diaper prior to closing
adhesive regions 15, 16 is illustrated at the right hand
side of Fig. 1: the diaper after securing adhesive regions
15, 16 to the backing sheet is illustrated at the left
hand side of Fig. 1.
As indicated earlier herein and as just described, the
operation of closing and fastening the diaper of the
present invention around the waist of the wearer (using
adhesive regions 15, 15) can be accomplished independently
of the operation of adjusting the fit of the diaper around
the thighs (using adhesive regions 16, 16) so as to most
effectively seal the diaper from undesirable leakage.
With the diaper of the present invention, a movement of
the user's leg in one dirèction will pull the diaper and
elastic portion around the thigh to the same direction and
cause the diaper to follow the body. There is less
J~D-109
--8--
relative movement of the body and the diaper with respect
to each other. This reduces the amount of "gapping"
between the thighs of the wearer and the diaper itself so
that the possibility of leakage is reduced.
In another embodiment, illustrated in Fiy. 2, an arcuate
slit 19, similar to slit 17, separates adhesive regions 15
and 1~ at each side of the diaper and extends inwardly and
downwardly from the side margin to terminate near the
upper end of elastic element 13. Arcuate slit 19
terminates in a circular cutout 18 which prevents the
diaper from ~earing when streæses are applied in the
regions surrounding the slit. In this embodiment, there
are no adhesive-free portions between adhesive region 15
and slit 19 or between adhesive region 16 and slit 19.
It will be understood the slits 17 and 13 allow the diaper
to be fitted and closed around the waist of the wearer
(using adhesive regions 15, 15) and to be fitted and
sealed against leakage at the thighs ~using adhesive 1~,
16) in separate, independent steps.
Fig. 4 illustrates the scheme of actuating forces in the
fastening system with a slit, wherein dot 15 represents
the adhesive region 15 for fitting the diaper around the
waist and dot 16 represents the adhesive region 16 for
fittinq the diaper to the legs. Arrows Fl and F2 are
possible exertions applied at the adhesive region.
Another embodiment of the diaper of the present invention
is illustrated in Fig. 5. Diaper 107 has a central
~ransverse axis, X-X, located midway between and parallel
to its upper edge 105 and lower edge 106 and a central
longitudinal axis, Y-Y, located midway between its opposed
side edges 115, 116, and intersecting the transverse axis
JBD-109
- 9 -
at right angles. Diaper 107 comprises a
liquid-impermeable backing sheet 118, an absorbent coee
119 and a liquid-permeable facing or covering sheet 120.
Diaper 107 further comprises an elastic element 114
secured between the backing sheet and the facing sheet in
the upper margin of the diaper and elastic elements 113,
113 in the central portions of the left and right side
margins.
The upper margin o~ the diaper, i.e., that portion lying
generally between upper edge 105 of the diaper and upper
edge ll9a of the absorbent batt, has a first region of
pressure sensitive adhesive which comprises a generally
rectangular adhesive area lOla at the upper right hand
corner of the diaper and a generally rectangular adhesive
area lOlb at the upper left hand corner. The lower
portion of the diaper, i.e., that portion thereof which is
nearer lower edge 106, has a second region of pressure
sensitive adhesive which comprises adhesive area 102a and
20 adhesive area 102b. Adhesive area 102a is loaated in the
right side margin of the diaper, i.e., that por~ion
thereof which lie~ between right side edge 116 of the
diaper and the extended right side edge ll9b of absorbent
core 119, and is spaced a short distance upwardly, i.e. in
the direction toward transverse axis, X-X, from lower edge
106. Adhesive area 102b is located in the left side
margin of the diaper, i.e. that portion thereo~ which lies
between left side margin 115 and the extended left side
edge ll9c of absorbent core 119, and is also spaced a
short distance upwardly, in the same fashion as adhesive
area 102a, from lower edge 106 of the diaper. Adhesive
areas lOla, lOlb, 102a and 102b are applied, e.g. by an
adhesive transfer process, to the exposed surface of
covering sheet 120.
~BD-109
-
--10--
It will be understood that adhesive areas lOla and lOlb
can be moved slightly downwardly from upper edge 105 or
slightly inwardly from side edges 116 and 115,
respectively. Adhesive areas lOZa and 102b can be shifted
slightly inwardly from side edges 116 and 115,
respectively, of the diaper.
Diaper 107 further comprises a pair of slits, 108a and
108b, in the lower portions of the right and left hand
margins, respectively, and arranged generally
symmetrically with respect to longitudinal axis, Y-Y.
Slit 108a is preferably arcuate in shape and extends
inwardly and toward transverse axis, X-X, from a point on
the righ~ side edge 116 of the diaper which lies between
adhesive area 102a and the point of juncture of righ~ side
edge 116 and lower edge 106 of the diaper.
Slit 108b has the same arcuate configuration as slit 108a
and extends inwardly and toward transverse axis, X-X, from
a point on the left side edge 115 of the diaper which lies
between adhesive area 102b and the point of juncture o~
le~t side edge 115 and lower edge 106 of the diaper. The
distance between lower edge 106 and the points where slits
108a and 108b meet side edges 116 and 115, respectively,
should be at least equivalent to the length, measured
parallel to longitudinal axis, Y-Y, of adhesive areas lOla
and lOlb.
Slits 108a and 108b terminate in a circular opening lll
located near elastic element 103 and inwardly of side
edges 116 and 115 respectively, of the diaper. It will be
understood that the radius o curvature of slits 108a and
108b may be varied and that these slits could be straight,
if desired. In any event, when slits 108a and 108b are
35 provided as aforeGaid, flaps 127 and 128 are formed at the
JBD-109
-
~z~z~
side margins of the diaper, with adhesive area 102a being
applied to and carried by flap 128 and adhesive area 102b
being applied to and carried by flap 127.
In use, a child to be diapered is positioned facing
upwardly on top of the diaper in the generally flat
configuration shown ;n Fig. 5 so that the child 1 6 buttocks
are disposed more or less centrally of the diaper. The
lower part of the diaper is brought up between ~he child 16
legs so that lower edge 106 i5 in alignment with upper
edge 105. Adhesive areas lOla and lOlb at upper edge 105
are inserted into 61its 108a and 108b, respectively, and
adhered to the backing sheet at the corner regions where
side edges 116 and 115, respectively, meet lower edge
106. This action fixes the diaper in position around the
child's waist. Flaps 127 and 128 are manipulated ~o
conform the diaper around the thighs of the child and are
then secured, by way of adhesive areas 102b and 102a
respectively, to the impermeable backing sheet 118. This
sequence is illustrated at the right hand side of Fig. 6
where flap 128 has been moved aside so that adhesive area
lOlb can be inserted into slit 108b as shown by
directional arrow A. After adhesive area lOlb has been
adhered to the backing sheet 118, flap 128 carrying
adhesive 102b is then brought into adhering contact with
the backing sheet. The diaper in its closed configuration
around the waist is illustrated at the left side of Fig. 6.
It should be understood that the present invention is not
limited to the descriptions and illustration6 of the
disclo6ed embodiments, thus being likely to be achieved in
different ways, however, within the scope of the following
claim6.
JBD-109
