Note: Descriptions are shown in the official language in which they were submitted.
~~.3~r'~~3~~~
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A DTSPOSAaLE SANITARY PAD
The present invention refers to disposable sanitary pads
that provide a lesser frequency of leakage.
More specifically, it refers to disposable sanitary pads
that provide a more effective contact of the product with
the external area of the perineal region of a user, thus
reducing the risk of leakage from the sides of the product.
In the scope of the invention, one considers hygienic pads
those absorbing devices intended to be used outside the
feminine body, usualll~ during her menstrual periods, to
receive arid retain menstrual and other vaginal discharges.
Disposable sanitary pads are designed to be abandoned
after they have collected the fluids from the feminine
body, without being used once again.
Sanitary pads are items of general consumption in modern
society and, for explanatory purposes, they can be divided
into three categories, namely:
-- tampons
- external pads
- hybrid pads, which have characteristics of the
other two types.
Tampons are pads that have the capacity of intercepting
menstrual discharge within the vaginal duct with little
risk of soiling the user's clothes. They are considered
superior protection means. Tn practice failures can occur
in their functioning as regards their capacity of
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effectively having radial expansion in function of the
fluid that causes expansion of the pad, thus sealing and
creating occlusion within the vaginal duct. Besides,
there are people who, for physical or psychological
reasons, are incapable of using tampons as effective
feminine protection means. Finally, they can present
insertion or removal problems; sometimes they are sticky
and difficult to handle, and in certain health cases there
is some medical restriction.
The so-called hybrid pads are those that incorporate
characteristics of tampons and external sanitary pads.
Sometimes they are called wads or labial pads or
vestibule-type pads, in which case a partial or total
insertion into the vulvar vestibule occurs.
In many of the cases described in the literature, one does
not take into account the anatomical cooperation with the
user's body to the effect that the sensitive tissues are
often distended by the obstructive geometry of certain
structural elements, that is to say, the so-called labial
pads find their functioning in friction contact with very
sensitive urogenital parts such as the vaginal orifice,
the urethral orifice and/or the clitoris. In other cases,
it is stated that a pad should be firmly fastened to the
user's intimate clothes with a portion of the pad located
inside the vestibule, and under most circumstances this
creates a friction effect inside that sensitive part.
Thus, according to U.S. Patents 2,092,342 and 3,905,372,
an element inside the vaginal opening is physically
connected to an external part, so that the relative
movement between the user's body and the underlying
structure of the pad causes discomfort, irritation and
even pain. In a similar way, U.S. Patent 3,983,873
J&J-1300
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describes flaps that are supported against the walls of
the labial space, in order to increase the retaining
forces of the pad. There are other vestibule-type pads
which are designed to eliminate this irritation factor by
relative movement involving body/product/user's clothes,
as in U.S. Patent 4,742,245; however, the disclosed
product is extremely sophisticated and is expensive to
manufacture.
External sanitary pads have been developed for use outside
the body near the vulvar region, to collect the menstrual
fluid, other vaginal discharges and possibly urine of
incontinent women.
In their simplest and more traditional form, such pads
comprise an absorbent core placed between a
fluid-permeable facing sheet (sometimes referred to as a
"top sheet") and a fluid-impermeable backing sheet.
The absorbent core, sometimes referred to herein as the
"absorbing element", is adapted to receive and absorb the
menstrual discharge and other vaginal discharges. The
absorbent core may comprise comminuted wood pulp fibers,
polymer foams, vegetable pulp, natural or synthetic fibers
or any other material which can absorb menstrual fluids or
the like body discharges. Wood pulp fibers are commonly
used as the major constituent of the absorbent core of
external sanitary pads.
The fluid-permeable facing sheet contacts the wearer°s
body rahen the sanitary pad is in use and permits the
menstrual or other vaginal discharge to pass therethrough
so as to be absorbed by the underlying absorbent core.
This facing sheet usually comprises a fluid-permeable
nonwoven fabric or a perforated plastic film. Although
J&J-1300
the facing sheet may be hydrophilic in nature, it is
preferred that it be hydrophobic in nature. In the latter
case, the menstrual or other discharge passes through the
fluid-permeable facing sheet but the sheet, owing to its
hydrophobic nature, tends to remain dry to the touch, thus
making the product more comfortable in use. Perforated
plastic films axe usually inherently hydrophobic.
Nonwoven fabrics, if they are not made of hydrophobic
fibers, can be rendered hydrophobic by treatment with,
ZO e.g. a repellent finish such as that pxovided by
fluorochemicals, wag emulsions or the like.
The purpose of tkie fluid--impermeable backing sheet, as its
name suggests, is to prevent the fluid collected by tire
absorbent core from leaking from the sanitary pad and
staining the clothing of the user. The backing sheet
usually comprises a thin film of plastic such as
polyethylene, although in some cases it might also
comprise other materials, e.g. a nonwoven fabric, which
has been suitably treated so as to be liquid impermeable.
If desired, the backing sheet may be moisture vapor
permeable, that is, it may allow moisture vapor to pass
therethrough while at the same time preventing the passage
of liquids.
Leakage, and the most most common is usually leakage of
menstrual blood at the sides, even in very small amounts,
is a great discomfort and embarrassment for the user. For
those skilled in the art, the goal aimed at in developing
such products is maximization of the flow of liquid in
direction Z (taking into account that, in a graph for
three-dimensional representation, axes X and Y represent
the horizontal plane, and azis Z is perpendicular to
them), since, in addition to the technical reasons that
fully justify this objective, there are psychological
J&J-1300
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reasons which show that a rapid Z-directional flow
minimizes the stain effect on the pad and, associated with
conditions of relatively dry top sheet, it has to do with
the feeling of safety, thus reducing the possibility of
embarrassment due to the failuxe of the pad. i.e. leakage.
The external pad of the traditional type is merely an
elongated rectangular product, made without any worry
about the user's anatomy. Thus, when in use, such a
product may undergo deformation that detracts from its
performance considerably and f<~vors frequent leakage.
Starting therefrom the improvements have followed one
another until the present prior art and have resulted,
either directly or indirectly, in lesser possibility of
leakage:
- by forming the absorbing sheets more anatomical than a
rectangle, for instance in the form of an hourglass;
- by causing the pad as a whole to take on the form of a
shell in order to fit between the user°s legs in a better
manner and be closer to her perineal area;
- by using top sheets that optimize the passage of
liquid towards the absorbing element and restrict the
return thereof in the opposite directions
- by creating more elaborate structures, for instance,
an absorbing element which is thicker in its central area
to bring about more proximity between the point of
discharge and the pad, side flaps that form barriers for
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leakage, overlapped structures such as in U.S. Patent No.
4,425,130, and others;
- by creating more absorbency by utilizing either
absorbing fibers or superabsorbing polymers. by varying
the density inside and along the traditional absorbing
sheet or with layers of varied materials, and others.
From this list of improvements it can be seen that the
optimization of the product with increasing complexity and
sophistication tends to make the product more and more
expensive with respect to the benefit obtained, which
consequently raises the price for the final consurner.
An examination of the reasons for the existence of leakage
in external sanitary pads indicates that it is necessary
to minimize the course of the vaginal discharge to the
point at which it meets the product that will collect and
retain such liquids. This is justified by the fact that
any course allows the fluid to flow over the skin adjacent
the place of discharge, to a greater or lesser extent,
obviously depending, for instance, upon the viscosity and
the surface tension of such a liquid. In this way, in
some cases it can even fall out of the reach of the
absorbing sheet and leak, thus causing discomfort,
embarrassment and the consequent feeling of unsafety for
the user. The conclusion is that a structure with an
excellent intrinsic performance as regards absorption and
leakage retention can function only from the moment at
which the contact of the liquid with such a structure
occurs, not before.
Thus, knowing the shortcomings of the prior art and the
functional needs after which those skilled in the art have
been seeking in this kind of product, as per the foregoing
J&J-1300
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considerations, one of the objects of the present
invention is to provide an external disposable sanitary
pad that will effectively minimize the risk of leakage at
the sides.
Another object is to provide an effective pad without
employing new materials and without making use of cornplex
and sophisticated structures that are difficult to
manufacture.
to
Still another object of the present invention is to
provide an effective and simple pad having a high
cost/benefit ratio.
In accordance with the present invention there is provided
a disposable sanitary pad characterized by containing at
least one line obtained by compression along and near each
longitudinal edge of the body of said pad. Such lines are
sufficiently apart from each other, so that the pzessure
exerted by the user's thighs on said product in use will
provide a protuberance towards the user's body, onto which
liquids are discharged.
The fuilctioning of the pad of the invention is based on
the fact that, when put into use, the product is
compressed on its central part by the user's thighs. This
compression causes the material contained between the two
lines, to be forced toward the user's body, thus making a
greater amount of material available for absorption close
to the discharge point, where the need for absorption is
more critical, in order to prevent the liquid from having
a free course with the possibility of escape over the
skin, thus reducing the risk of leakage.
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When the two lines are not present, as is the case of the
prior art, the absorbing material under the pressure of
the user's thighs tends to move away from her body, or
still to take on a casual conformation that does not
provide a better contact at the discharge point.
This means that, unlike what exists in the prior art, the
disposable sanitary pad of the invention manages to
provide a protuberance of absorbing material, to optimize
the contact with the user's body, without the need for
using additional absorbent material for this purpose.
As used herein, the expression "compression line" or "line
obtained by compression" means that the body of the
sanitary pad is subjected to a pressure along a line
sufficient to create, in a non-resilient manner, a greater
density with respect to the surrounding material. Such
lines - there are at least two of them - may or may not be
straight, parallel to each other and to the longitudinal
edges. and can have any thickness. Preferably, the lines
are parallel to the longitudinal edges and their width is
less than 5mm, since in this way they will favor the
formation of the protuberance when the product is put into
use.
Between a line created by a low compression, a poorly
defined one, and another created by a higher compression,
a more defined one, the latter is preferred, since it
intensifies the capacity of an absorbing sheet to form the
protuberance toward the user°s body under the pressure of
her thighs. However, a compression beyond a certain value
has the disadvantage of creating a line of hard material
to the extent of detracting from the user's comfort. The
existence of a single compression line along each
longitudinal edge is preferred. However, two or more
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lines close to each other along each longitudinal edge, or
any other configuration that is not considerably
detrimental to the appearance of the protuberance during
use of the product are also included in the scope of the
invention.
As used in this teat, the expression °°longitudinal edges"
means the edges along the length of the absorbing material
of the sanitary pad of the in~rention. This expression
doss not refer to the ends slang the length of the product
which can also have side flaps that extend beyond the
absorbing element.
The expression "along and close to each longitudinal
edge", as used here, means that the distance from one line
obtained by compression to the nearest longitudinal edge
is smaller than the distance between said one line and the
other line obtained by compression near the opposite
longitudinal edge. Since the compression lines are
regions of preferential conduction of liquids due to the it
greater density, they are not so close to the longitudinal
edges to the extent there is a risk of leakage, nor are
they so close to each other that the formation of the
aforementioned protuberance is hindered. Preferably, the
distance from the compression line to the nearest
longitudinal edge is of from about 5 to about 30% of the
breadth of the absorbing element. and more preferably from
about 5 to about 20% of the breadth of the absorbing
element.
The distance between the compression lines is also a
function of the material or materials that constitute the
absorbing element, which vary in resilience, density,
fiber length, etc. An intrinsic property of the
compression lines known to those skilled in the art and
J&J-1300
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that can be associated with the invention is that they
provide a preferential way of liquid conduction and serve
to conduct (or "wick") the discharged fluid to regions
further away from the point of discharge, that is to say,
they serve to spread the liquid along the whole absorbing
element in a more homogeneous and rapid manner, thus
providing less time of contact of the liquid with the
user's skin and helping to avoid leakage, which would
happen in the event of an abundant menstrual discharge in
a single place without compression lines to help to
distribute it.
Some quite common practical embodiments of sanitary pads
made use of elastic means associated with side flaps along
the length of the product and of a batt of wood-pulp
fibers as an absorbing element; it should be noted that a
certain compactation of the absorbing element occurs
during storage of the product. Such elastic means provide
the product with anatomical curves and folds, and the
resilience of the wood-pulp fibers causes the latter to
settle in a preferential manner near the anatomical curves
and folds, thus giving way to undesired regions of higher
density and, therefore. of lesser absorption speed,
usually around the focus of menstrual discharge. The
compression lines impart cohesion to the pulp panel, thus
providing it with resistance to resilient movements of its
fibers at places beneficial to the product, i.e. along the
longitudinal edges, where they can lead the discharged
liquid to more remote regions of the absorbing element and
provide the aforementioned protuberance when in use.
As used herein, the term "body" of the pad is understood
to comprise at least the absorbing element and can include
any other layers, a.g. the facing sheet and the backing
sheet, placed on, under or inside it. Thus, the
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-11-
compression lines may be impressed only upon the absorbing
element, if so desired. or on any other structural element
comprising the body of the pad. For ezample, the
compression lines may be made in both the facing layer and
the absorbing element.
The preferred method for creating the compression lines is
by placing on the absorbing body a relief pattern made of
an adequate material having the desired form and pressing
it to mark the material of the: absorbing element
sufficiently to create the compression lines, by
hot-pressing if necessary. The surface of the absorbing
element put into contact with the relief pattern is the
one facing the user's body; otherwise the pressure exerted
by the user's thighs would undesirably favor the formation
of the protuberance on that surface of the absorbing
element facing away from the body.
An example of industrial realization consists in providing
a rotatory cylinder with various equal relief patterns
arranged along its perimeter and passing the
absorbing-element batts between this cylinder and a moving
belt under pressure sufficient to provide the compression
lines on said batts.
The disposable sanitary pad of the invention is not
limited to any specific type of structure and can
optionally comprise:
- liquid-permeable cover sheets of nonwoven fabric or
perforated plastic films, either with or without
embossing, either separate or in combination with other
materials, having either hydrophobic or hydrophilic
characteristics, and others;
J&J-1300
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- a unilayer or multilayer sheet made of wood pulp or
other vegetable pulp, polymeric or natural foam,
hydrophobic fibers, either separate or mixed among
themselves, containing superabsorbing polymers with areas
having differentiated densities, etc.;
- either with or without means to attach it to the
user's clothes;
- an external backing sheet made of either totally or
partially hydrophobic material or materials, whether
respirable or not, monolayer or multilayer, etc.;
- either with or without the presence of elastic means;
- rectangular, in the form of an hourglass or any other
adequate form.
The compression lines are necessarily located close to the
longitudinal edges of the region designed to receive the
menstrual discharge and should have a length of preferably
about lcm to about l2cm, and more preferably about 2 to
about 8cm.
In a preferred embodiment of. the invention, the
compression lines are not located only along the
longitudinal edges but also they complementarily extend
toward the regions that do not receive the menstrual
discharge directly, but rather they have.a direction
tending toward each other until. they meet and go on in
both directions. This is austified by the fact that, in
this embodiment, the more rapid and homogeneous
distribution of the liquid collected in the absorbing
element is optimized.
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CA 02009894 1999-03-17
- 13 -
However, this does not exclude embodiments in which
the compression lines do not meet or are radially
subdivided or any other embodiment that can
distribute the collected liquid without being
considerably detrimental to the ability to form a
protuberance between the compression lines when
subjected to the pressure of the user's thighs.
According to a broad aspect of the present invention
there is provided a disposable sanitary pad which
comprises an absorbing element comprising
longitudinal and transverse centerlines, first and
second longitudinal edges, first and second
transverse ends and a body-facing side. First and
second compression lines are formed in the absorbing
element. Each of the lines comprises a central
segment extending substantially longitudinally so
that a central portion of the body-facing side is
disposed between the central segments. The lines are
formed by compression on the body-facing side so that
pressure against the longitudinal edges by a user's
thighs causes the body-facing side of the central
portion to assume a convex shape so as to protrude
toward a user's body. Each of the first and second
compression lines have a first end segment connected
to the central segment. The first end segments
extend both toward each other and toward the first
transverse end so as to form an acute angle with a
longitudinal centerline, whereby at least the first
portion of fluid deposited proximate the transverse
centerline is wicked along the compression lines
toward a portion of the absorbing element disposed
along the longitudinal centerline and proximate the
first transverse end. The first end segment of the
first compression line is connected to the first end
segment of the second compression line.
CA 02009894 1999-03-17
- 13a -
The present invention will be illustrated in
connection with the disposable sanitary pad described
and claimed in Brazilian Patent Application
PI 8601226. It is understood that this example is
given merely by way of illustration and is not
intended to limit the scope of the appended claims.
In the appended drawings:
- Figure la is a top plan view of the product
before thermocontraction of the elastic means
employed;
- Figure lb is a schematic cross-section taken
along the line I-I of Figure la;
- Figure 2a is a perspective view of the pad of
Figure 1 after thermocontraction of the elastic means
employed;
- Figure 2b is a schematic cross-section taken
along line II-II of Figure 2a;
- Figure 3 is a schematic cross-section of the
configuration assumed by the sanitary pad of
Figure la when in use;
- Figure 4 shows a schematic representation of
other arrangements of compression lines which may be
utilized in the practice of the present invention.
CA 02009894 1999-03-17
- 14 -
Referring now to the accompanying drawings, there is
shown an external sanitary pad 30 in accordance with
the teachings of the present invention. Pad 30,
which is elongated in configuration and has rounded
upper and lower end edges 16 and 17, respectively,
comprises a fluid-permeable facing sheet 1, an
absorbing element or absorbent core 3, and a fluid
impermeable backing sheet 2. Pad 30 further
comprises a pair of elastic elements 6,6' located
adjacent longitudinal side edges 18,19, respectively,
of the pad. Pad 30 includes compression lines 10,
11, 12a, 12b, 12c, 12d, 13a and 13b which will be
described in greater detail hereinafter. As can be
seen, for example, in Figure lb of the drawings,
facing sheet 1 and backing sheet 2 are coextensive in
width. Sheets 1 and 2 are also coextensive in
length. The absorbing element 3 has a length which
is less than the length of the facing and backing
sheets and a width which is less than the width of
the facing and backing sheets. Absorbing element 3
has a pair of longitudinal side edges 9,9', a rounded
top edge 21, and a rounded bottom edge 22 which,
taken together, define the perimeter of the absorbing
element. The absorbing element is located between
facing sheet 1 and backing sheet 2 in the manner best
seen in Figure lb of the drawings. Facing sheet 1
and backing sheet 2 are secured to each other, e.g.,
by heat-sealing, in their marginal portions, that is,
those portions lying between the perimeter of the
absorbing element 3 and the perimeter of pad 30 which
is defined by the aforementioned top edge 16, bottom
edge 17, and two longitudinal side edges 18,19.
Longitudinal side flaps 4,5 are provided in sanitary
pad 30 as a result of the securing together of
sheets 1 and 2 in the manner just mentioned.
-15-
Elastic elements 6,6° are located between facing sheet 1
and backing sheet 2 in longitudinal flaps 4,5,
respectively, of pad 30. These elastic elements are in an
extended but elastically contractable state when pad 30 is
in the flat configuration shown in Fig, la. When the
elastic elements are permitted to retract from their
extended state, the sanitary pad assumes the "boat-like"
configuration shown in Figure 2a. The elastic elements
may comprise one or more rubber monofilaments which are
secured, e.g. by the use of a hot melt adhesive, between
the facing and backing sheets in the manner seen in Figure
lb. Preferably, however, a strip of thermoplastic film
which contracts and becomes elastic upon treatment with
heat is used for the elastic elements. Several heat
shrinkable thermoplastic films which have elastic
properties after being heat shrunk are known in the art.
We prefer to use strips of a heat shrinkable copolymer of
ethylene and vinyl acetate having a basis weight of about
35g per square centimeter, a length of about l3cm, a width
of about lcm and a thickness of about 30 microns.
Preferably, the elastic'elements have a length which is
about 60% of that of the pad 30 and are centered from end
to end of the pad. The aforementioned strips of heat
shrinkable copolymer are secured in their relaxed state
between the facing and backing sheets by the use of heat
sealing equipment which provides a series of spaced,
transversely oriented lines of securement 7 as shown in
Fig, la. Lines of securement 7 are separated one from the
other by regions 8 in which there is no sealing. When the
heat shrinkable elastic elements 6 are secured between the
facing and backing sheets by the use of heat-sealing
procedures as just described, the heat which is applied
will also serve to contract the elements 6,6° and thereby
provide them with their elastic properties. If the heat
shrinkable elastic elements 6.6' are secured by the use of
J&J-1300
CA 02009894 1999-03-17
- 16 -
e.g. an adhesive, it is necessary to thereafter treat
those elements with heat, e.g., by the use of hot
air, in order for them to contract and obtain their
elastic characteristics. When the elastic elements
6,6' are in their retracted state, the sanitary
pad 30 assumes the anatomical, shell-like
conformation shown in Figures 2a and 2b. Side flaps
4,5 and portions of the sanitary pad adjacent thereto
are raised upwardly so that, as seen in Figure 2b,
the flaps form an angle of about 30° to the horizontal
plane 36 of pad 30 in its flat configuration
illustrated in Figure lb.
Preferably, although not necessarily, the fluid-
permeable facing sheet 1 is a non-woven fabric
comprising heat-sealable polyester fibers and having
a basis weight of 22g/m2 with 144 perforations per
square inch. Fluid-impermeable layer 2 preferably
comprises a film of polyethylene having a basis
weight of 19g/cm2 and a thickness of about 0.020mm.
When facing sheet 1 comprises heat-sealable polyester
fibers and backing sheet 2 comprises polyethylene,
the facing and backing sheets may be sealed together
in their marginal portions by heat sealing
techniques. In the preferred embodiment, absorbing
element 3 comprises a layer of 100% wood pulp fluff
having a weight of about 7 grams. In a typical
sanitary pad, absorbing element 3 is about 20cm in
length and about 6cm in width. Absorbing element 3
is sandwiched between liquid-permeable facing sheet 1
and liquid-impermeable backing sheet 2 in known
fashion.
In one embodiment of the invention, sanitary pad 30
comprises a first pair of compression lines 10,11,
running parallel to the longitudinal side edges 9,9'
CA 02009894 1999-03-17
- 16a -
of absorbing element 3. For a sanitary pad 30 having
a length of 22cm, compression lines 10,11 are
conveniently about 6cm in
_17_ ~~4~~3~~3~-'~
length (between points A and B and between points A' and
B' in Figure la) and are spaced slightly inwardly (about
0.8cm) from the longitudinal side edges 9,9' of absorbing
element 3. The compression lines 10,11 are substantially
centrally located between the top and bottom edges of the
pad.
In a second and more preferred embodiment, sanitary pad 30
further comprises four additional compression lines. As
seen in Figure la, a pair of compression lines extends at
an angle from the ends of each compression line 10,11
toward points (C and C' in Figure la) which lie on the
longitudinal centerline 33 of sanitary pad 30. Thus, at
the upper end of pad 30, a third compression line 12a
extends from the upper end A' of first compression line 10
to a first point C located on centerline 33 between said
end A and the upper edge 18 of the pad. Similarly, a
fourth compression line 12b extends from the upper end A
of second compression line 11 to first point C. A second
pair of angularly disposed compression lines 12c,12d is
provided near the bottom portion of the sanitary pad.
Fifth compression line 12c extends from the lower end B'
of first campression line 10 to a second point C' located
on centerline 33 between said end B' and the lower edge 17
of pad 30. A sixth compression line i2d extends from the
lower end B of second compression line 11 to second paint
C' located on centerline 33.
It will toe observed that when compression lines 10, 11,
12x, 12b, 12c, and 12d axe disposed in the manner dust
described, they form the elongated hexagonal configuration
best seem in Fig. la.
Still referring to Fig. la, first compression line 10 and
second compression line 11 run parallel to each other and
J&J-1300
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~~.3~~~~~
to longitudinal side edges 9,9° of absorbing element 3.
Tn a typical sanitary pad 30 having a length of about 22cm
and a width of about Sam and comprising an absorbing
element 3 having a length of about 20cm and a width of
about 6cm, compression lines 10 and 11 have a length of
about 6cm and a width of about 0.15cm. Typically,
compression lines 10 and 11 would be separated by a
distance of about 4cm.
In another embodiment of the invention, sanitary pad has a
further pair of compression lines extending along
longitudinal centerline 33. Thus, as seen in Fig. 1a, a
seventh compression line 13a extends from point C to point
D on longitudinal centerline 33 in the direction of the
upper end of the sanitary pad. Similarly, an eighth
compression line 13b eztends from point C° to point D' on
a longitudinal centerline 33 in the direction of the lower
end of the sanitary pad. i~hen pad 30 and compression
lines 10, 11, 12x, 12b, 12c, and 12d have the typical
lengths mentioned hereinabove, compression lines 13a and
I3b typically have a length of l.5cm. It will be
recognized by those skilled in the art that the various
dimensions mentioned herein for pad 30, absorbing element
3 and the several compression lines are typical dimensions
only and these dimensions may be varied without departing
from the spirit and scope of the invention.
A steel plate having ridges corresponding to the desired
pattern of compression lines may be employed to form the
aforementioned compression lines. By way of illustration,
the absorbing element may be placed on a fined surface and
thereafter covered with said steel plate so that the
ridges thereof are in contact with the upper surface of
the absorbing element. The steel plate is then pressed
against the absorbing element, using a ~lorgren hydraulic
J&J-1300
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press at a pressure of 9 psi, to form the compression
lines.
Figure 3 shows the pad of Figure 2 in use, placed into
contact with the perineal area 40 of the user. Under
pressure of the user°s thighs 12 and 13, the protuberance
14 is formed between the compression lines 10,11. The
flaps 4 and 5 lie against the user°s thighs and are also
useful for restricting leakage Pram the sides.
Figure 4 shows three examples of the conformation of
compression lines used in the invention. Under ,~ the
compression lines do not meet; under ~ the compression
lines meet and diverge radially toward the farthest areas
of the pad; under ~ two compression lines are employed
along each longitudinal edge.
A test has been carried out with the sanitary pad of the
invention, as illustrated in Figure 2, with a group of 17
women.
Each woman received 7 pads according to the invention,
that is, with compression lines called herein Group A
pads) and another 7 pads similar to the previous ones but
without the compression lines (called herein Group B pads).
Each woman wore the pads during the menstruation period,
alternating Group A and Group B pads. The average time of
use of each pad was 4 hours.
After use, each pad was checked concerning the formation
of the central protuberance, and the occurrence of leakage
through the sides.
J&d-1300
-20- ~E~~;~~~.~~
The results were:
~!0% more products from Group A than from Group B pads
showed the formation of the central protuberance, putting
in evidence the fact that the use of compression lines as
disclosed by the invention lead to their formation.
- 5% less products from Group A than from Group B pads
showed signs of leakage at the sides, showing that the
protuberance near the discharge point as disclosed by the
invention helps to prevent leakage.
20
30
J&J-1300
