Note: Descriptions are shown in the official language in which they were submitted.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
1
ADHESIVE COMPONENT FOR OSTOMY DEVICES
Field of the Invention
The present invention relates to a collecting device for attachment to human
skin
and for collecting bodily waste e.g. an ostomy device.
Background
Collecting devices for collecting bodily waste, ostomy appliances, wound or
fistulae drainage bandages or devices for collecting urine are usually in the
form
of a receptacle, e.g. a bag, pouch or tube for receiving the waste, connected
to
an adhesive wafer that can be attached to the skin of the patient. The wafer
is
typically in the form of a backing layer coated on the skin-facing surface
with an
adhesive layer and the wafer may further be provided with an aperture for
accommodating the body opening. The size and shape of said aperture can often
be adapted individually to fit the anatomy of the patient.
One of the crucial parts of such devices is the adhesive wafer. The wafer
should
be able to fit leak proof around the body opening, have good adherence to the
skin without unintended detachment from the skin, but at the same time be easy
to remove again without damaging the skin. Furthermore, the wafer should be
able to follow the movements of the body and be comfortable to wear.
When designing a skin adhesive one of the major issues is to keep the skin
relatively dry underneath the adhesive to prevent maceration. Maceration
occurs
when skin is unable to get rid of moisture from transpiration and outlet from
a
body opening. This may result in degradation of the skins barrier function as
well
as bad adhesion of the device to skin.
Usually, skin adhesive keeps the skin dry by absorbing moisture. This allows
moisture to transport through the adhesive from the skin side to the opposite
side, where it is allowed to evaporate.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
2
Adhesives for fastening a bodily waste collecting pouch or tube are usually
covered by a moisture impermeable layer that does not allow moisture from the
skin to permeate through the adhesive and out into the surroundings.
Therefore, adhesives for fastening a collecting pouch or tube are made
moisture
absorbent. Absorbing particles or hydrocolloids (HC) are mixed into an
adhesive
matrix in order to absorb moisture from the skin and thereby the skin is kept
relatively dry. This technique is well known in the art and forms the basis
for most
commercially available ostomy adhesives see, e.g. US 4,192,785.
The major problem in using an absorbing adhesive is the changes in the bonding
properties when the adhesive absorbs moisture. An absorbing adhesive normally
starts out being a well-bonded adhesive and usually ends up being a weak-
bonded adhesive after absorbing moisture. This effect is particularly a
problem
for hydrocolloid-based adhesives. As the adhesive absorbs moisture from the
skin, the hydrocolloids swell and take up an increasing amount of space in the
skin-bonding zone, thereby reducing the skin bonding effect of the adhesive.
The weak-bonded adhesive will usually still keep the collecting device
attached to
the skin, however the risk of leakage of bodily waste along the skin surface
will
increase drastically.
Hence, there is a need to find a solution to avoid leakage of bodily waste
occurred because of weak-bonded adhesive and still maintain the ability to use
conventional waste collecting devices to adhere to the skin.
It has now surprisingly been found that the component according to the
invention
provides a sealing element that can be used in combination with conventional
waste collecting devices.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
3
Summary of the invention
The present invention relates to a component for sealing a body opening and
for
use in combination with a body waste collecting device, said component
comprises a soft adhesive composition wherein the soft adhesive composition
comprises a liquid impermeable, moisture permeable adhesive composition.
Brief description of the drawing
The invention is disclosed more in detail with reference to the drawings in
which
Figure 1-5 show different embodiments of the invention.
Detailed description of the present invention
The aim of the invention is to provide a sealing component for use in
combination
with a body waste collecting device. The sealing component is to be used as a
supplement to the collecting device.
By body waste collecting device is meant a device being able to collect and
hold
the output in a collecting item for a predefined time. The holding in place of
the
device may be obtained by a skin adhesive and the collection may be obtained
by a bag.
In an embodiment of the invention a component for sealing a body opening and
for use in combination with a body waste collecting device, comprises a soft
adhesive composition wherein the soft adhesive composition comprises a liquid
impermeable, moisture permeable adhesive composition.
The component comprising the soft adhesive composition is used for security
and
protection for the user in order to avoid leakages and to obtain longer wear
time.
Standard pressure sensitive adhesives used today are more or less plastic,
which
means that the adhesive will get a good grip by flowing into cavities of the
skin
mantles. This results in a large adhesion area and thus a good skin adhesion
enhanced by the mechanical anchoring.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
4
A standard and conventional hydrocolloid pressure sensitive adhesive is a skin
friendly adhesive that is capable of adhering to the skin, handling
perspiration by
absorbing the moist and being removable from the skin without essential
damage.
A typical pressure sensitive adhesive is based on a polyisobutylene, PIB
(adhering substance) and a carboxy methyl cellulose, CMC (absorbing media).
When using conventional hydrocolloid containing adhesives, the adhesive wafer
tends to be relatively stiff caused by the choice of adhesive materials as
well as
the high filling rate of hydrocolloids (typical 30-60 % w/w). Incorporation of
hydrocolloids ensures that the perspiration of moisture from the skin is
absorbed
in a way that the skin will not macerate due to constant water exposure. As a
side
effect the hydrocolloids tend to swell from exposure of the water containing
output. In general the tack of a hydrocolloid adhesive tends to decrease due
to
the absorption of the moisture perspiration from the skin into the adhesive.
Even with the decreased tack, the adhesive will usually keep the collecting
device
attached to the skin where the device is applied. Unfortunately, however, the
decreased tack may cause a leakage of body fluids from the body opening along
the skin surface.
The component according to the invention compensates for this leakage failure
using the mechanical and adhesive properties of a liquid impermeable, moisture
permeable adhesive, thus achieving a solution to the problem of conventional
waste collecting devices.
A liquid impermeable, moisture permeable adhesive does not absorb the
moisture but rather permeates the water away from the skin surface.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
By permeable adhesive is meant an adhesive where the moisture vapour
transmission rate, MVTR is higher than 100g/m2/24h as measured using the
method disclosed herein.
5 The adhesive used in the component of the present invention has a high
moisture vapour transmission rate, preferably a MVTR over 100 g/m2/24hrs,
which makes it breathable and very skin friendly. The high moisture
transmission
of the adhesive is a particular advantage where a medical device has to be
worn
on the skin for a long time, e.g. days.
Another important property of the component of the invention is that the
adherence force of the soft adhesive used does not change with time, or
changes
only to a small extent with time, during wear time of the device.
The component comprising a liquid impermeable, moisture permeable adhesive
composition gives a soft, tight and pliable adhesive in the perianal,
peristomal or
fistal area with optimal protection. The soft adhesive offers a virtually non-
erosive
and non-swellable solution yet a skin friendly breathable, liquid impermeable,
moisture permeable adhesive.
The fixation of the component will add skin friendliness and extreme
flexibility
giving the user of the collecting device an optimal security and non-traumatic
solution.
According to one embodiment of the invention, the soft adhesive composition
comprises the liquid impermeable, moisture permeable adhesive composition,
which comprises a permeable polymer selected from the group of but not limited
to polypropyleneoxide, polyurethane, silicone, polyacrylate, ethylene vinyl
acetate
and mixtures thereof.
As used herein a permeable polymer means a polymer that absorbs less than 5%
in wt, preferably less than 1%, at equilibrium and has a moisture vapour
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
6
transmission rate greater than 100 g/m2/24hrs, preferably greater than 200
g/m2/24 h rs.
According to an embodiment of the invention, the water vapour permeability of
the soft adhesive composition comprising the liquid impermeable, moisture
permeable adhesive composition is higher than 100g/m2/24h as defined herein.
As used herein liquid impermeable means that water is rejected from
penetrating
the substance by simple flow.
In one embodiment of the invention, the permeable polymer is crosslinked.
As used herein a crosslink means a small region in a macromolecule (polymer
chain structure) from which more than 2 chains emanate. The linking may be
covalent, physical or ionic.
In another embodiment of the invention, the liquid impermeable, moisture
permeable adhesive composition comprises a block copolymer.
As used herein a block copolymer means a copolymer in which the repeating
units in the main chain occur in blocks, e.g., -(a)m-(b)n-(a)p-(b)q-, where a
and b
represent the repeating units and m, n, p, q, are numbers.
In a preferred embodiment of the invention, the liquid impermeable, moisture
permeable adhesive composition comprises polypropyleneoxide.
In a preferred embodiment of the invention, the liquid impermeable, moisture
permeable adhesive composition comprises polyurethane.
In a preferred embodiment of the invention, the liquid impermeable, moisture
permeable adhesive composition comprises ethylene vinyl acetate.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
7
The adhesive composition comprising ethylene vinyl acetate may suitably be an
adhesive known in the art such as the adhesive composition disclosed, for
example in Danish patent application PA 2007 01003.
In a preferred embodiment of the invention, the liquid impermeable, moisture
permeable adhesive composition comprises silicone.
In a preferred embodiment of the invention, the liquid impermeable, moisture
permeable adhesive composition comprises polyacrylate.
It may be advantageous that the soft adhesive composition comprises absorbent
particles. According to an embodiment of the invention, the soft adhesive
composition comprises absorbent particles.
The particles may be absorbent articles such as salts, hydrocolloids,
microcolloids and/or super absorbers in order for the composition to absorb
moisture from skin.
Microcolloid particles are well-known in the art, e.g. from International
Patent
Application No. WO 02/066087, which discloses adhesive compositions
comprising microcolloid particles. The microcolloid particles may have a
particle
size of less than 20 microns.
The soft adhesive composition may comprise 1-30 % w/w of hydrocolloid (HC) or
super absorbent particles (SAP) particles, more preferred 5-30% w/w particles.
In the conventional adhesive constructions a high amount of hydrocolloids are
needed in order to obtain an absorption into the adhesive. The reason for this
is
that the polymer matrix is impermeable to moisture so the filler particles
have to
be packed very close or in contact to each other. The absorption into the
adhesive will occur through direct water transfer between two absorbing
particles
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
8
or by absorption in one particle resulting in a volume increase that generates
contact to the next particle.
The absorption according to this embodiment of the invention has a polymer
matrix that is permeable to moisture in a way that moisture will permeate
through
the polymer matrix into the absorbing particles. In order to obtain the same
absorption speed, less absorption particles are then needed.
Salt may be advantageous to use as absorber in the component of this
invention.
A salt like sodium chloride has an equilibrium vapour pressure of about 75% RH
at skin temperature and will absorb water from skin and output because of the
difference in vapour pressure.
In an embodiment of the invention the soft adhesive composition comprises
particles of mineral salt. The salt may be present in an amount of 1-50 % w/w,
more preferred in an amount of 5-25%.
The salt can be an inorganic salt or an organic salt.
According to one embodiment of the invention, the soft adhesive composition
comprises water soluble inorganic salt from the group of but not limited to
NaCI,
CaCl2, K2SO4, NaHCO3, Na2CO3, KCI, NaBr, Nal, KI, NH4CI, AIC13 and mixtures
thereof, preferably NaCI.
According to another embodiment of the invention, the soft adhesive
composition
comprises water soluble organic salt from the group of but not limited to
CH3COONa, CH3COOK, HCOONa, HCOOK and mixtures thereof.
As used herein a paste is a moldable or flowable adhesive that is able to
adhere
to the skin, flow or being permanently pressed into irregularities of the skin
and
thus protecting the skin from the output. A paste is usually used as an
accessory
to stoma care products for sealing around the stoma.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
9
Sealing an opening refers to protection of an opening from output for example
use of a paste around a stoma at the rim of the perineal skin or the rim of a
fistula.
The component for sealing the body opening can have elastic or plastic
characteristics.
According to one embodiment of the invention, the collecting device comprises
a
collecting pouch and an adhesive wafer.
In an embodiment of the invention, the component is located on the skin-facing
surface of the adhesive wafer.
By the skin-facing surface of the adhesive is meant the side adhering to the
skin.
By located is meant where the component is placed on the collecting device and
specifies the position of the component on the collecting device.
In another embodiment of the invention, the component is located on the pouch-
facing surface of the adhesive wafer.
By the pouch-facing surface or non-skin-facing surface is meant the side of
the
adhesive or backing pointing away from the skin (non-bonding side).
According to another embodiment of the invention, the component is located at
the inner rim of the adhesive wafer.
By the inner rim portion of the adhesive wafer is meant the portion in the
perianal,
peristomal or fistal area. This area of the adhesive is exposed to faeces as
well
as perspiration. The properties of the inner rim portion depend on wear time,
output type and anatomy among others.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
According to one embodiment of the invention the component is located at the
outer rim of the adhesive wafer.
By the outer rim portion of the adhesive wafer is meant the portion
essentially
5 outside the welding zone or coupling. This portion is less exposed to faeces
but
has to handle perspiration as well as mechanical exposure due to movements
and pull from the bag.
According to an embodiment of the invention the component is in the form of a
10 ring.
By an adhesive ring is meant an adhesive, essentially surrounding the body
opening that needs to be drained or a ring covering the outer or inner rim of
the
adhesive wafer.
According to an embodiment of the invention, a hole of the ring having a
diameter
that is less than the diameter of a hole in the adhesive wafer. By this
embodiment the component will have a tighter fit around the body opening
compared to the adhesive wafer. In one embodiment the sealing and the tighter
fit of the component is obtained by turtle necking.
According to one embodiment of the invention, the component is part of a ring
such as a half ring covering 180 degrees of a circle.
According to an embodiment of the invention, the component covers the entire
skin-facing surface of the adhesive wafer.
Optionally, the component only covers a part of the adhesive wafer.
According to an embodiment of the invention, the component partly covers the
adhesive wafer.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
11
According to another embodiment of the invention, the component partly covers
the skin-facing surface of the adhesive wafer.
According to another embodiment of the invention the adhesive wafer has a
recess for adapting the component.
The collecting device could be pre-shaped with a recess that fits the
component
to be combined with the device. A recess could be a cut-out of part of the
adhesive wafer.
By adapting is meant that the component is placed on the collecting device in
a
way that almost integrates the two separate parts.
The component according to the invention can be used in connection with
adhesive wafer having a conventional hydrocolloid containing pressure
sensitive
adhesive usable for skin. However, the component is also usable in connection
with other types of adhesives applied on the adhesive wafer.
According to an embodiment of the invention, the body opening is a stoma.
According to another embodiment of the invention, the body opening is a
fistula.
According to another embodiment of the invention, the body opening is an anus.
By a body opening is meant a natural or artificial body opening such as an
anus,
a stoma, or a fistula.
According to an embodiment of the invention, the collecting device is an
ostomy
appliance.
According to another embodiment of the invention, the collecting device is a
faecal collecting device.
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
12
According to another embodiment of the invention, the collecting device is a
fistula collecting device.
Description of the preferred embodiments
The invention is now explained more in detail with reference to the drawings
showing preferred embodiments of the invention.
Figures 1-5 are all drawings of a side view of the left half of the adhesive
wafer
and the component according to the invention. All wafers are covered with a
backing layer. The skin-facing surface is illustrated in the drawings as the
downward side of the wafer and the backing layer is placed on top of the
wafer.
Figure 1 shows an adhesive wafer (11) and a component (12) where the
component only covers part of the adhesive wafer and is placed on the surface
of
the skin-facing adhesive wafer. The component can optionally be covered by a
second backing layer placed in between the non-skin-facing side of the
component and the skin-facing side of the adhesive wafer.
Figure 2 illustrates a side view of an adhesive wafer (21) partly covered with
a
component (22) in the outer rim portion of the wafer.
Figure 3 illustrates a side view of an embodiment of the invention where the
hole
of the ring of the component (32) has a diameter that is less than the hole in
the
adhesive wafer (31).
Figure 4 illustrates a side view of another embodiment of the invention where
the
hole of the ring of the component (42) has a diameter that is less than the
hole in
the adhesive wafer (41) and wherein the sealing is obtained by a turtleneck
effect.
Figure 5 illustrates a side view of an adhesive wafer (51) having a recess for
adapting the component (52).
CA 02692753 2010-01-06
WO 2009/006900 PCT/DK2008/050144
13
EXPERIMENTAL PART
Methods
Determination of water absorption
In order to get better correlation between measured water absorption and
actual
performance in a humanlike environment, a modified version of the ISO 62
standard was used: Pieces of adhesive of 1x25x25 mm3 were fastened on a
piece of glass using double sided adhesive and the constructs were immersed in
saline water (0.9% NaCI in dematerialized water) at 32 C. After 24 hours the
samples were removed and carefully dripped dry and weighed. The change in
weight was recorded and reported as weight gain in percent of the original dry
weight of the adhesive. In the following we will call this value w24n
Determination of moisture vapour transmission rate (MVTR)
MVTR was measured in grams per square meter (g/m2) over a 24 hours period
using an inverted Paddington cup method (British Pharmacopoeia,
1993,Addendum 1996, page 1943. HMSO London): A container or cup being
water and water vapour impermeable having an opening was used. 20m1 saline
water (0.9%NaCI in demineralised water) was placed in the container and the
opening was sealed with the test adhesive film. The container, with a
duplicate,
was placed into an electrically heated humidity cabinet and the container or
cup
was placed up side down in a way that the water was in contact with the
adhesive. The cabinet was maintained at 37 C and 15% relative humidity (RH).
After about an hour, the containers were considered to be in equilibrium with
the
surroundings and it was weighed. 24h after the first weighing, the containers
were weighed again. The difference in weight was due to evaporation of vapour
transmitted through the adhesive film. This difference was used to calculate
Moisture vapour transmission rate or MVTR. MVTR was calculated as the weight
loss after 24h divided by the area of the opening in the cup (g/m2/24h). If
the
adhesive film could not support the weight of the water, a supporting film
with
very high permeability was used as support.
