U.S. patent application number 16/926791 was filed with the patent office on 2020-10-29 for adhesive composition adapted for attachment to skin.
The applicant listed for this patent is Coloplast A/S. Invention is credited to Dorrit Diana Israelson, Charlotte Klein, Henrik Olsen.
Application Number | 20200338230 16/926791 |
Document ID | / |
Family ID | 1000004954162 |
Filed Date | 2020-10-29 |
United States Patent
Application |
20200338230 |
Kind Code |
A1 |
Israelson; Dorrit Diana ; et
al. |
October 29, 2020 |
ADHESIVE COMPOSITION ADAPTED FOR ATTACHMENT TO SKIN
Abstract
An adhesive composition is provided that is adapted for
attachment to skin. The adhesive composition includes
styrene-ethylene/butylene-styrene, polyolefin, polybutene, wax,
polyacrylic acid, and an absorbent material.
Inventors: |
Israelson; Dorrit Diana;
(Espergaerde, DK) ; Olsen; Henrik; (Copenhagen OE,
DK) ; Klein; Charlotte; (Broenshoej, DK) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Coloplast A/S |
Humlebaek |
|
DK |
|
|
Family ID: |
1000004954162 |
Appl. No.: |
16/926791 |
Filed: |
July 13, 2020 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
15754592 |
Feb 23, 2018 |
10744224 |
|
|
PCT/DK2016/050284 |
Aug 24, 2016 |
|
|
|
16926791 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08L 23/20 20130101;
C08L 23/147 20130101; C08L 33/02 20130101; A61L 24/043 20130101;
A61L 27/06 20130101; A61L 24/10 20130101; A61L 24/046 20130101;
A61L 2400/14 20130101; C08L 53/02 20130101; A61L 24/08 20130101;
C08L 23/08 20130101; A61L 24/06 20130101; A61L 24/0031
20130101 |
International
Class: |
A61L 24/04 20060101
A61L024/04; C08L 53/02 20060101 C08L053/02; A61L 24/06 20060101
A61L024/06; A61L 24/00 20060101 A61L024/00; A61L 27/06 20060101
A61L027/06; A61L 24/08 20060101 A61L024/08; A61L 24/10 20060101
A61L024/10 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 24, 2015 |
DK |
PA 2015 70544 |
Claims
1. An adhesive composition for attachment to skin, the adhesive
composition comprising 4-9% (w/w)
styrene-ethylene/butylene-styrene, 3-6% (w/w) polyolefin, 35-41%
(w/w) polybutene, 2-4% (w/w) wax, 4-20% (w/w) polyacrylic acid, and
a total of 20-40% (w/w) of one or more absorbent material(s).
2. The composition according to claim 1, wherein the composition
consists of 4-9% (w/w) SEBS, 3-6% (w/w) polyolefin, 35-41% (w/w)
polybutene, 2-4% (w/w) wax, 4-20% (w/w) PAA, and a total of 20-40%
(w/w) of one or more further absorbent material(s).
3. The composition according to claim 1, wherein the composition
has an absorption at 2 hours, measured as described herein, of at
least 0.1 g/cm.sup.2/2 h.
4. The composition according to claim 1, wherein the composition
has an absorption at 24 hours, measured as described herein, of at
least 0.5 g/cm.sup.2/24 h.
5. The composition according to claim 1, wherein the composition
has a gel strength, measured as described herein, below 4 N.
6. A device for attachment to a skin surface of a user, the device
comprising an adhesive composition according to claim 1 and at
least one release liner.
7. The device according to claim 6, wherein the device has a
skin-facing surface and a surface facing away from the skin during
use, and wherein the release liner is disposed on the skin-facing
surface.
8. The device according to claim 6, wherein a second release liner
is disposed on the surface facing away from the skin during
use.
9. The device according to claim 6, wherein the device is ring or
oval shaped with a through-going hole for fitting around a stoma of
the user.
10. The device according to claim 6, wherein the outer diameter of
the device is in the range 30-60 mm.
11. The device according to claim 6, wherein the diameter of the
hole is in the range 10-25 mm.
12. The device according to claim 6, wherein the thickness of the
device, including release liner(s) is in the range 3.5-5.5 mm.
13. A method of using of the adhesive device according to claim 6,
comprising the steps of providing a device according to claim 6,
removing the at least one release liner from the device, and
attaching the device to a skin surface surrounding a stoma.
14. The method according to claim 13, comprising a further step of
attaching the device to an adhesive baseplate of an ostomy
device.
15. The method according to claim 13, wherein the device has a
skin-facing surface and a second surface facing away from the skin
during use, with the release liner is disposed on the skin-facing
surface, the method further comprising removing the release liner
from the skin-facing surface of the device.
16. The method according to claim 13, wherein the device has a
skin-facing surface and a second surface facing away from the skin
during use, with the release liner is disposed on the second
surface, the method further comprising removing the release liner
from the second surface of the device.
17. The method according to claim 13, wherein the device is ring or
oval-shaped with a through-going hole for fitting around a stoma of
the user, the method further comprising placing the through-going
hole around the stoma and attaching the ring or oval-shaped device
to a skin surface surrounding the stoma.
Description
FIELD OF THE INVENTION
[0001] The invention relates to an adhesive composition for
attachment to skin.
BACKGROUND
[0002] In connection with surgery for a number of diseases in the
gastro-intestinal tract, in many cases, a consequence is that the
colon, the ileum or the urethra has been exposed surgically. The
patient is left with an abdominal stoma and the effluents or waste
products of the body, which are conveyed through these organs, are
discharged through the artificial orifice or opening and are
collected in a collection bag. The bag is usually adhered to the
skin by means of an adhesive wafer or plate having an inlet opening
for accommodating the stoma. A separate ring-shaped adhesive and/or
an adhesive paste may be used as an accessory for filling an area
between the stoma and the adhesive wafer.
SUMMARY
[0003] Provided is an adhesive composition for attachment to skin,
the composition comprising an adhesive polymer component selected
from the group consisting of a mixture of a polyethylene copolymer
and polypropylene glycol (PPG), and
styrene-ethylene/butylene-styrene (SEBS) block copolymer; the
composition further comprising polyolefin, polybutene, polyacrylic
acid (PAA), and at least one further absorbent material.
[0004] In embodiments, the adhesive polymer component is a mixture
of a polyethylene copolymer and polypropylene glycol (PPG).
[0005] In embodiments, the polyethylene copolymer is selected from
the group consisting of poly(ethylene vinyl acetate) (PEVA),
poly(ethylene vinyl acetate carbon monoxide), poly(ethylene butyl
acetate), poly(ethylene vinyl alcohol), poly(ethylene butyl
acrylate), and poly(ethylene butyl acrylate carbon monoxide).
[0006] In embodiments, the polyethylene copolymer is PEVA.
[0007] In embodiments, the adhesive polymer component is a
styrene-ethylene/butylene-styrene (SEBS) block copolymer.
[0008] In embodiments, the composition comprises 10-15% (w/w), such
as 10-13% (w/w), such as 10-12% (w/w) of the polyethylene
copolymer. In embodiments, the composition does not comprise
polyethylene copolymer.
[0009] In embodiments the polyethylene copolymer is a polar
polyethylene copolymer. In embodiments, the polyethylene copolymer
is poly(ethylene vinyl acetate) (PEVA). In embodiments the PEVA has
a vinyl acetate content of at least 40% (w/w), such as at least 50%
(w/w), such as at least 60% (w/w), such as at least 70% (w/w). In
embodiments, the PEVA has a vinyl acetate content of 40-80% (w/w),
such as 50-80% (w/w), such as 60-80% (w/w). In embodiments, the
PEVA has a vinyl acetate content of 70% (w/w). In embodiments, the
PEVA is LEVAMELT 700 from Lanxess.
[0010] In embodiments, the composition comprises 15-20% (w/w), such
as 16-19% (w/w), such as 16-18% (w/w) PPG. In embodiments, the
composition does not comprise PPG.
[0011] In embodiments, the PPG has an average molecular weight of
1.000-3.000 g/mol. In embodiments, the PPG has an average molecular
weight of 2.000 g/mol. In embodiments, the PPG is Voranol 2000 L
from Dow Chemical Company.
[0012] In embodiments, the composition comprises 4-9% (w/w), such
as 5-8% (w/w), such as 6-7% (w/w) SEBS. In embodiments, the
composition does not comprise SEBS.
[0013] In embodiments, the SEBS block copolymer has a polystyrene
content of 20-40% (w/w) based on the final weight of the block
copolymer, preferably 25-35% (w/w), more preferably 28-32% (w/w).
In embodiments, the SEBS block copolymer is a Kraton G1726 M
polymer from Kraton Performance Polymers Inc. having a polystyrene
content in the range 29.2-31.6 (w/w).
[0014] In embodiments, the composition comprises 3-18% (w/w)
polyolefin. In embodiments, the composition comprises 14-18% (w/w),
such as 15-17% (w/w) polyolefin. In embodiments, the composition
comprises 3-6% (w/w), such as 4-5% (w/w) polyolefin.
[0015] In embodiments, the polyolefin is a copolymer of propylene
and ethylene. In embodiments, the polyolefin is Eastoflex E1016PL-1
Amorphous Polyolefin from Eastman Chemical Company.
[0016] In embodiments, the composition comprises 10-46% (w/w)
polybutene. In embodiments, the composition comprises 11-15% (w/w),
such as 12-14% (w/w) polybutene. In embodiments, the composition
comprises 36-40% (w/w), such as 37-39% (w/w) polybutene.
[0017] In embodiments, the polybutene has a number average
molecular weight of 4,000-8,000, such as 5,000-7,000, such as
6,000. In embodiments, the polybutene is Indopol Polybutene Grade
H-18000 from INEOS.
[0018] In embodiments, the composition comprises 4-20% (w/w), such
as 4-10% (w/w), such as 4-8% (w/w), such as 5-7% (w/w) PAA. In
embodiments, the composition comprises 8-12% (w/w), such as 9-11%
(w/w) PAA.
[0019] In embodiments, the PAA is crosslinked PAA. In embodiments,
the PAA is partially neutralized PAA. In embodiments, the PAA is
Carbopol 974P NF Polymer from Lubrizol Advanced Material, Inc. In
embodiments, the PAA has a carboxylic acid content in the range
56-68%. In embodiments, the PAA has a viscosity of 20,000-50,000
cP, such as 25,000-45,000 cP, such as 25,000-40,000 cP, such as
29,400-39,400 cP at 25 degrees Celsius when measured with a
Brookfield RVT at 20 RPM and neutralized to pH 7.3-7.8 using 0.5 wt
% mucilage and spindle no. 6.
[0020] In embodiments, the composition comprises a total of 20-40%
(w/w), such as 25-40% (w/w), such as 25-30% (w/w) or 29-35% (w/w)
or 30-40% (w/w), such as 35-40% (w/w) of one or more further
absorbent material(s).
[0021] In embodiments, the one or more further absorbent
material(s) is selected from the group consisting of hydrocolloid,
starch, water soluble salt, mono, di- and oligosaccharides, sugar
alcohols, polypeptides, organic acids, inorganic acids, amino
acids, amines, urea, super absorbent particles such as polyacrylic
acid, glycols such as polyethylene glycol, fumed silica, and
bentone.
[0022] In embodiments, the at least one further absorbent material
is selected from the group consisting of hydrocolloid, starch,
water soluble salt, mono, di- and oligosaccharides, sugar alcohols,
polypeptides, organic acids, inorganic acids, amino acids, amines,
urea, super absorbent particles such as polyacrylic acid, glycols
such as polyethylene glycol, fumed silica, and bentone. In
embodiments, the hydrocolloid is selected from guar gum, locust
bean gum, pectin, potato starch, alginates, gelatine, xantan or gum
karaya, cellulose derivatives, salts of carboxymethyl cellulose,
sodium carboxymethyl cellulose, methyl cellulose, hydroxypropyl
cellulose, hydroxyethyl cellulose, sodium starch glycolate, and
polyvinylalcohol. In embodiments, the water soluble salt is
selected from NaCl, CaCl.sub.2, K.sub.2SO.sub.4, NaHCO.sub.3,
Na.sub.2CO.sub.3, KCl, NaBr, NaI, KI, NH.sub.4Cl, AlCl.sub.3,
CH.sub.3COONa, CH.sub.3COOK, HCOONa, and HCOOK. In embodiments, the
at least one further absorbent material is hydroxyethylcellulose
with a weight average molecular weight in the range
500,000-2,000,000 g/mol, such as 750,000-1,500,000 g/mol, such as
800,000-1,200,000 g/mol, such as 1,000,000 g/mol. In embodiments,
the at least one further absorbent material is Natrosol 250HX
hydroethylcellulose from Ashland.
[0023] In embodiments, the composition further comprises a wax.
[0024] In embodiments, the composition comprises 1-5% (w/w), such
as 2-4% (w/w) wax.
[0025] In embodiments, the wax is a microcrystalline wax. In
embodiments, the wax is a polyethylene wax. In embodiments, the wax
is Sasolwax 7837 from Sasol Wax GmbH.
[0026] In embodiments, the composition comprises 10-14% (w/w)
polyethylene copolymer, 15-20% (w/w) PPG, 13-18% (w/w) polyolefin,
10-15% (w/w) polybutene, 1-5% (w/w) wax, 4-8% (w/w) PAA, and a
total of 30-35% (w/w) of one or more further absorbent
material(s).
[0027] In embodiments, the composition consists of 10-14% (w/w)
polyethylene copolymer, 15-20% (w/w) PPG, 13-18% (w/w) polyolefin,
10-15% (w/w) polybutene, 1-5% (w/w) wax, 4-8% (w/w) PAA, and a
total of 29-35% (w/w) of one or more further absorbent
material(s).
[0028] In embodiments, the composition comprises 4-9% (w/w) SEBS,
3-6% (w/w) polyolefin, 35-41% (w/w) polybutene, 2-4% (w/w) wax,
8-12% (w/w) PAA, and a total of 35-40% (w/w) of one or more further
absorbent material(s).
[0029] In embodiments, the composition consists of 4-9% (w/w) SEBS,
3-6% (w/w) polyolefin, 35-41% (w/w) polybutene, 2-4% (w/w) wax,
8-12% (w/w) PAA, and a total of 35-40% (w/w) of one or more further
absorbent material(s).
[0030] In embodiments, the composition has an absorption at 2
hours, measured as described herein, of at least 0.1 g/cm.sup.2/2
h, such as at least 0.15 g/cm.sup.2/2 h, such as 0.15-3.0
g/cm.sup.2/2 h. An absorption of at least 0.1 g/cm.sup.2/2 h is
deemed acceptable for ensuring that the composition can absorb
sufficient liquid to properly transport moisture away from the skin
surface and keep the skin dry. A higher absorption, such as at
least 0.15 g/cm.sup.2/2 h, is preferable, provided that such higher
absorption does not lead to an insufficient gel strength.
[0031] In embodiments, the composition has an absorption at 24
hours, measured as described herein, of at least 0.5 g/cm.sup.2/24
h, such as at least 0.6 g/cm.sup.2/24 h, such as 0.6-1.1
g/cm.sup.2/24 h. An absorption of at least 0.5 g/cm.sup.2/24 h is
deemed acceptable for ensuring that the composition can absorb
sufficient liquid to properly transport moisture away from the skin
surface and keep the skin dry. A higher absorption, such as at
least 0.6 g/cm.sup.2/24 h, is preferable, provided that such higher
absorption does not lead to an insufficient gel strength.
[0032] In embodiments, the composition has a gel strength, measured
as described herein, below 3 N, such as below 2 N, such as below 1
N. In embodiments, the composition has a gel strength, measured as
described herein, in the range 0.75-1.5 N or 1-2 N. A gel strength
of below 3 N is deemed acceptable for ensuring that residue is very
rarely left on the skin when removing an adhesive composition that
has absorbed liquid. Preferably, the gel strength is below 2 N,
which ensures that practically no residue is left on the skin when
the adhesive composition has absorbed liquid and is subsequently
removed from the skin.
[0033] In embodiments, the composition has an absorption at 2
hours, measured as described herein, of 0.15-0.30 g/cm.sup.2/2 h
and an absorption at 24 hours, measured as described herein, of
0.6-1.1 g/cm.sup.2/24 h, and a gel strength, measured as described
herein, in the range 0.75-1.5 N. A composition with absorption and
gel strength in these ranges exhibit a good balance between
absorbent and cohesive properties.
[0034] Provided is an adhesive composition for attachment to the
skin, the composition comprising an adhesive polymer and one or
more absorbent materials, wherein the composition has an absorption
at 2 hours, measured as described herein, of 0.15-0.30 g/cm.sup.2/2
h and an absorption at 24 hours, measured as described herein, of
0.6-1.1 g/cm.sup.2/24 h, and a gel strength, measured as described
herein, in the range 0.75-1.5 N.
[0035] In embodiments, the composition comprises polyacrylic
acid.
[0036] In embodiments, the composition has a G* at 1 Hz, measured
as described herein, in the range 45,000-1,500,000 Pa. In
embodiments, the G*, measured as described herein, at 40 Hz is in
the range 200,000-3,000,000 Pa. In embodiments, the G*, measured as
described herein, at 10 Hz is in the range 100,000-2,500,000 Pa. In
embodiments, the G*, measured as described herein, at 0.1 Hz is in
the range 15,000-1,000,000 Pa. In embodiments, the G*, measured as
described herein, at 0.003 Hz is in the range 3,000-400,000 Pa. In
embodiments, the composition has G* values within the above recited
ranges for all mentioned frequencies. In preferred embodiments, the
composition has a G* at 1 Hz, measured as described herein, in the
range 75,000-1,000,000 Pa, such as 75,000-500,000 Pa, such as
75,000-300,000 Pa.
[0037] In embodiments, the composition has a tan(delta) at 1 Hz,
measured as described herein, in the range 0.5-3. In embodiments,
the composition has a tan(delta) at 40 Hz, measured as described
herein, in the range 0.5-2. In embodiments, the composition has a
tan(delta) at 10 Hz, measured as described herein, in the range
0.5-3. In embodiments, the composition has a tan(delta) at 0.1 Hz,
measured as described herein, in the range 0.5-3. In embodiments,
the composition has a tan(delta) at 0.003 Hz, measured as described
herein, in the range 0.35-2.5. In embodiments, the composition has
tan(delta) values within the above recited ranges for all mentioned
frequencies. In preferred embodiments, the composition has a
tan(delta) at 1 Hz, measured as described herein, in the range
0.6-1.5, such as 0.7-1.0 or 1.0-1.5.
[0038] G* and tan(delta) values in the above ranges for various
frequencies ensure that the composition has a good balance between
elastic and plastic properties.
[0039] In embodiments, the composition is mouldable. In
embodiments, mouldable is defined as being capable of significant
non-elastic deformation when a user applies pressure to the
composition. In embodiments, the composition is capable of at least
10%, such as at least 20%, such as at least 30% non-elastic
deformation. By non-elastic deformation is meant that the
composition essentially retains its shape after deformation with
elastically reverting to its original shape. In embodiments, the
composition retains at least 70%, such as at least 80%, such as at
least 90% of its adhesion at 10% deformation. In embodiments, the
composition retains at least 70%, such as at least 80%, such as at
least 90% of its adhesion at 20% deformation. In embodiments, the
composition retains at least 70%, such as at least 80%, such as at
least 90% of its adhesion at 30% deformation. In this context,
adhesion is measured as peel force.
[0040] Provided is an adhesive device for attachment to a skin
surface of a user, the device comprising an adhesive composition as
described herein and at least one release liner.
[0041] In embodiments, the device has a skin-facing surface and a
surface facing away from the skin during use, and the release liner
is disposed on the skin-facing surface.
[0042] In embodiments, a second release liner is disposed on the
surface facing away from the skin during use.
[0043] In embodiments, the adhesive device is ring or oval shaped
with a through-going hole for fitting around a stoma of the
user.
[0044] In embodiments, the outer diameter of the device is in the
range 30-60 mm, such as 40-50 mm. If the device is not circular,
the outer diameter is to be understood as the maximum diameter,
meaning the maximum length from edge to edge of a line through the
centre of the device.
[0045] In embodiments, the diameter of the hole is in the range
10-25 mm, such as 15-20 mm. If the hole is not circular, the outer
diameter is to be understood as the maximum diameter, meaning the
maximum length from edge to edge of a line through the centre of
the hole. The device may be made in versions with different sized
holes in order to fit around different sized stomas.
[0046] In embodiments, the thickness of the device, including
release liner(s) is in the range 3.5-5.5 mm, such as 4-5 mm. In
embodiments, the thickness of the device, excluding release liners,
is in the range 2-3 mm.
[0047] In embodiments, the device is an adhesive barrier ring for
fitting around a stoma.
[0048] Provided is a use of the adhesive device as described
herein, comprising the steps of [0049] providing the adhesive
device, [0050] removing one or more release liners from the device,
[0051] attaching the device to a skin surface surrounding a
stoma.
[0052] In embodiments, the use comprises a further step of
attaching the device to an adhesive baseplate of an ostomy device.
In embodiments, the adhesive device is attached to the baseplate
before the adhesive device is attached to the skin. In such a
situation, the adhesive device is first adhered to the baseplate
and the baseplate with the adhesive device is then attached to the
skin surrounding the stoma. In embodiments, the adhesive device is
attached to the skin and the baseplate is subsequently attached to
the adhesive device and/or the skin surrounding the stoma.
DETAILED DESCRIPTION
[0053] Provided is an adhesive composition for attachment to skin.
In embodiments, the adhesive composition is for attachment around
the stoma of an ostomy device user. The adhesive composition may be
used to provide a seal around the stoma and can be used in
combination with a regular ostomy device comprising a collecting
pouch and an adhesive wafer. In such a situation, the user will
sometimes start by fitting the adhesive composition closely around
the stoma and will then apply the adhesive wafer of the ostomy
device on top of or immediately next to the adhesive composition.
Alternatively, the user may start by applying the adhesive
composition to the adhesive wafer of the ostomy device before
attaching the combined device to the skin surrounding the stoma. In
either way, a tight and secure seal can be provided around the
stoma, thereby protecting against leakage.
[0054] The adhesive composition is absorbent, meaning that it is
capable of absorbing liquid from the surroundings. This will allow
the composition to absorb moisture from the skin around the stoma,
which will help keep the skin surface dry, thereby preventing
damage to the skin.
[0055] The adhesive composition is preferably mouldable, meaning
that it can be shaped by the user applying pressure to the
composition. By being mouldable, the composition can be shaped to
closely match the shape of a given stoma and thereby provide a
tight seal around the stoma.
[0056] In order to use the adhesive composition, any release liners
are first removed and the adhesive compositions, typically in the
form of a ring, is placed on the skin surrounding the stoma. The
adhesive composition may then be moulded by pressing it in order to
make it fit closely around the stoma. When the adhesive device has
been secured around the stoma, a regular ostomy device, including
an adhesive wafer and a collecting bag, may be attached to the skin
and/or the outer surface of the adhesive device around the
stoma.
[0057] After use, the composition is removed from the skin,
optionally together with the ostomy device, and discarded.
[0058] When designing an adhesive composition for use on the skin,
it is preferable that the composition can absorb moisture from the
skin and that it can be easily removed in one piece. Generally,
when an adhesive composition absorbs liquid, the adhesive
composition will swell and become less cohesive. In other words,
absorption of liquid will to some degree compromise the
cohesiveness or structural integrity of the adhesive composition
and will increase the risk that the adhesive breaks apart when
removed from the skin. Such breaking apart during removal is
referred to as cohesive failure and will result in adhesive residue
being left on the skin of the user. This is problematic because
such residue will be difficult to remove and will make it hard to
attach a new adhesive to the skin.
[0059] For these reasons, it is desirable to achieve a good balance
between absorption and cohesion. A high absorption will make sure
the skin is kept dry and healthy while a high cohesion will mean
that the adhesive can be removed in one piece without leaving
significant residue.
[0060] The present inventors have identified adhesive compositions
that strike a good balance between absorption and cohesion.
Particularly, the inventors have found that adhesive compositions
with ingredients within the claimed ranges will ensure both
sufficient absorption and cohesion.
[0061] While the capabilities of absorption for the present
adhesive composition are similar to traditional hydrocolloid
adhesives, the new composition provides an additional high
gel-strength, which makes the seal coherent and durable. Thus,
during wear-time, the new composition will not dissolve and erode
as easily because the increased gel-strength prevents it from
breaking up into little pieces. In regards to pouch system change,
this means that the new adhesive composition should leave less
residue and come off in one piece along with the baseplate.
Moreover, a high durability should increase the possibility of
extended wear-time if needed.
Dynamic Mechanical Analysis (DMA)
[0062] The DMA was carried out as follows by a frequency sweep at
32.degree. C. and 1% CD (controlled deformation). Samples were
prepared by thermoforming to a 1 mm thick adhesive film between two
release liners. With a punching tool, a round sample of 25 mm in
diameter was cut out. The release liners were removed and the
samples placed in an Anton Paar Physica MCR 301 rheometer. The
geometry applied was parallel plates 25 mm and the force applied
was 5 N. After applying 5 N force, 15 minutes of thermal
equilibration of the samples at 32.degree. C. were carried out
before the measurements.
Moisture Absorption
[0063] Samples were prepared by thermoforming to a 1 mm thick
adhesive film between two release liners. With a punching tool,
samples were punched out. Sample size was 25.times.25 mm. The
release liners were removed. The samples were glued to an object
glass and placed in a beaker with physiological salt water and
placed in an incubator at 37.degree. C.
[0064] The sample was weighed at the outset (M(start)) and after 2
hours (M(2 hours) and/or 24 hours (M(2 hours)). Before weighing,
the object glass was dried off with a cloth. For a 25.times.25 mm
sample the area was 6.25 cm.sup.2 (the surface edges were left out
of the area). The moisture absorption may be calculated as: Water
absorption after 2 hours=(M(2 hours)-M(start))/6.25 cm.sup.2. The
result is in the unit g/cm.sup.2 per 2 hours. Water absorption
after 24 hours=(M(24 hours)-M(start))/6.25 cm.sup.2. The result is
in the unit g/cm.sup.2 per 24 hours.
Gel Strength
[0065] The cohesiveness or structural integrity of the adhesive
composition following significant absorption is evaluated by
testing the gel strength of the adhesive composition. A 1 mm thick
sample of the adhesive composition is immersed in isotonic saline
for 24 hours and the strength of the resulting swelled adhesive is
tested by pressing a probe into the gel and measuring the distance
travelled as a function of the force. A low number means that the
probe is only able to be pushed a short distance into the sample at
a given force, thus signifying a high gel strength, corresponding
to a high cohesion and structural integrity.
Examples
[0066] The following materials were used in the tested
compositions:
[0067] Cellulose: Natrosol 250HX hydroethylcellulose from
Ashland.
[0068] Gelatine: UF 220 from PB Gelatins.
[0069] Guar Gum FG-200 from Nordisk Gelatine.
[0070] Poly(acrylic acid) (PAA): Carbopol 974P NF Polymer from
Lubrizol Advanced Material, Inc.
[0071] Polybutene: Indopol Polybutene Grade H-18000 from INEOS.
[0072] Poly(ethylene vinylacetate) (PEVA): Levamelt 700 from
Lanxess. Pre-irradiated to increase molecular weight, 22 kGy.
[0073] Polyolefin: Eastoflex E1016PL-1 Amorphous Polyolefin from
Eastman Chemical Company.
[0074] Polypropylene glycol (PPG): Voranol 2000 L from Dow Chemical
Company.
[0075] Potato starch M3 from Kartoffelmelcentralen in Denmark.
[0076] Sodium carboxy methyl cellulose (CMC): Akucell AF 2881 from
Akzo.
[0077] Styrene-ethylene/butylene-styrene (SEBS) block copolymer:
Kraton G1726 M polymer from Kraton Performance Polymers Inc.
[0078] Wax: Sasolwax 7837 from Sasol Wax GmbH.
[0079] The components were mixed on a Herman Linden Z blade mixer
at a chamber temperature of 95.degree. C. and a mixing speed of 20
rpm. The polymer components were added first and mixed. Then the
absorbent components were added to the mixture and further
mixed.
[0080] Measurements were carried out on four exemplary adhesive
compositions falling within the scope of the invention
(compositions number 56, 86, 61, and 94).
[0081] For comparison, measurements were also carried out on two
commercial adhesive barrier ring products, namely the Eakin barrier
ring from ConvaTec Inc. and the Adapt barrier ring from Hollister
Inc. Analysis performed by the inventors has shown that the Eakin
barrier ring is a polyolefin-based adhesive comprising
hydrocolloids, most likely a type of cellulose and guar gum.
Importantly, the Eakin barrier ring does not comprise poly(acrylic
acid). The Adapt barrier ring also does not comprise poly(acrylic
acid). These products were measured as described herein, also using
a sample thickness of 1 mm.
[0082] The composition of the tested adhesives is indicated in the
table below. The amount of the different components are all given
as % (w/w). Absorption after 2 hours is given as "Abs, 2 h", is
measured as described herein and has the unit g/cm.sup.2/2 h.
Similarly, absorption after 24 hours is indicated as "Abs, 24 h",
is measured as described herein, and has the unit g/cm.sup.2/24 h.
Gel strength is measured as described herein and has the unit
Newton (N).
TABLE-US-00001 Composition number/product 56 86 61 94 Eakin Adapt
EVA 11.2 12.52 PPG 16.8 18.78 SEBS 6.2 6.618 Polyolefin 13.7 16.5
3.1 3.3 Polybutene 11.6 14 37.2 39.78 Wax 2.6 3.1 3.1 PAA 5 6 20 15
Cellulose 20 18 20 15 Guar gum 5 5 CMC 4 5.3 10.3 Gelatine 7.1
Alginate 19.1 Potato starch 5 Abs, 2 h 0.19 0.20 0.22 0.29 0.40
0.46 Abs, 24 h 0.67 0.62 0.81 1.04 0.84 1.13 Gel strength 1.1 1.2
0.9 0.9 4.6 5.1
[0083] All of the tested compositions, including the two
comparative examples with the commercial Eakin and Adapt products,
display sufficient water absorption at 2 h and 24 h to be usable on
skin. The Eakin and Adapt products display somewhat higher
absorption after 2 h than the tested inventive compositions. After
24 h, the absorption has levelled out, with the compositions 56 and
86 showing a tendency to be slightly lower than the rest, although
still well within the range usable for skin adhesives.
[0084] The inventive compositions display significantly higher gel
strength (lower numbers in the gel strength test as described
herein) when compared to the commercial adhesive products. This
means that the inventive compositions are much more cohesive after
absorption and retain their structural integrity, even after having
absorbed large amounts of liquid. In use, this means that the
inventive compositions can easily be removed from the skin in one
piece after use, without leaving significant residue on the skin of
the user.
[0085] In conclusion, the inventive compositions all display a good
balance between sufficient absorption and excellent gel strength.
This means that the compositions are capable of absorbing moisture
and keep the skin sufficiently dry during use, while at the same
time maintaining their cohesion and structural integrity enough so
that the adhesive composition does not fall apart during removal
leaving residue on the skin.
[0086] It is hypothesized that the balance between the polymer
adhesive ingredients and the absorbent materials in the composition
gives rise to these beneficial properties. In particular, the
inventors hypothesize that the use of PAA is an important factor in
achieving the balance between good absorption and good cohesion. As
is evident from the table above, the exact nature of the additional
absorbent materials does not appear to be essential. Also, the
presence of a wax is not essential.
[0087] Importantly, the beneficial effects are obtained with both a
PEVA-PPG mixture and with a SEBS copolymer as the adhesive polymer
component.
[0088] As illustrated by the Eakin and Adapt commercial products,
it is possible in other ways to achieve any one of absorption,
cohesion, and mouldability in isolation. The challenge faced by the
instant inventors was to create an adhesive composition that was
both sufficiently absorbent, and cohesive after absorption, as well
as, preferably, mouldable. This challenge was met by designing
adhesive compositions with exactly the right balance between gel
strength and absorption. The inventors hypothesized that such a
balance would lead to a more durable product that would be less
prone to fall apart during removal or leave residue on the
skin.
Clinical Study
[0089] In order to test the inventor's hypothesis and follow up on
the laboratory tests described above, a clinical study was carried
out to confirm the link between the right balance between gel
strength and absorption and possible beneficial properties in
actual use. In order to build on the laboratory data, the clinical
study product was designed to have properties in the relevant
intervals, namely a gel strength of 0.9-1.2, an absorption at 2 h
of 0.19-0.29 g/cm.sup.2/2 h, and an absorption at 24 h of 0.67-1.04
g/cm.sup.2/24 h. The composition was provided as a mouldable
sealing ring (referred to herein as the "Brava.RTM. Protective
Seal" or "new seal"). The product was presented to ostomy users and
the individual users were asked to compare the new composition to
their currently used product. A total of 135 users were included
with 34% normally using the Eakin Cohesive, 31% using the Brava
Mouldable Ring, 18% using the Adapt product, and 17% using other
commercial products.
Results
[0090] As an overall result, 53% of the participants indicated a
preference for the new seal as compared to their usual seal (see
table below).
TABLE-US-00002 Preferred seal Users New seal 53% Usual seal 27% No
preference 20%
[0091] This is a very significant result, especially because it is
well-known that ostomy users typically are very reluctant to change
their products and accessories. Once a user has learned to use a
given product and feels comfortable using it, that user is very
unlikely to wish to change to a different product. That 53% of the
users in the clinical study immediately preferred the new seal over
their own current seal is therefore a highly promising result that
speaks to the very meaningful advantages experienced by users
trying the new seal.
[0092] Users evaluated both usual seal and the new seal, Brava.RTM.
Protective Seal to be easy or very easy to stretch and mold,
answered by 81% and 85%, respectively. Easiness of application was
also evaluated well; with 75% and 86% answering, that the seal was
easy or very easy to apply, for usual and new seal, respectively.
In addition, 93% answered that the new seal came off the stomach in
one piece, which in comparison was answered by 87% for usual
seal.
[0093] Sixteen percent of users evaluated high or very high degrees
of residues on fingers after application of usual seal versus only
8% after application of new seal. In regards to peristomal skin
residues, 23% of users evaluated that the new seal left `no`
residues on the stomach, compared with 6% after test of usual seal.
Moreover, 57% reported very few and few residues on the stomach
after test of new seal compared with 42% for usual seal. Thus, the
new seal left significantly fewer residues on the stomach than
usual seal. If there were residues left, the cleaning of skin was
also evaluated to be easier after removal of new seal than with
usual seal. Also, ostomy bag change is generally made easier and
quicker by less residue being left on the skin.
[0094] Sixty-nine percent of the users evaluated the new seal to be
much or very much durable versus 59% for usual seal. Thus, the new
seal was by users evaluated to be significantly more durable than
usual.
[0095] In line with a high durability, expectations to wear time
tend to be evaluated higher for the new seal than for the usual
seal.
[0096] In supplemental analysis, durability and wear time were
explored across type of stoma and brand of seal. Stoma type and
usual brand did have some influence on the given evaluations. For
all three stoma-types; ileo-, uro- and colostomy users evaluated
durability higher (in the best category "very much") for the new
seal compared with their usual seal. Users with either an urostomy
or a colostomy evaluated durability and expectations to wear time
well. For users with an ileostomy the evaluations were two-sided.
One out of ten evaluated much higher durability and expectations to
wear time than for usual seal and a similar amount evaluated poorer
durability and expectations.
[0097] After having evaluated usual and new seal, users were asked
to give a preference of seal and why. Users should provide a
maximum of three reasons. As mentioned herein above, significantly
higher preference was observed for the new Brava.RTM. Protective
Seal compared with the usual seal, with 53% of users preferring the
new seal versus 27% who preferred usual seal. The primary reasons
for preference of new seal were; due to less residues, evaluated by
56%, and less worry about leakage and better feeling of security,
evaluated by 46% of users, on both parameters. The 27% who
preferred usual seal, reported it was due to better feeling of
security (63%), and less worry about leakage (54%). Preference for
usual seal due to less residues was evaluated by only 11%, compared
to 56% for the new seal.
[0098] Based on the above-described absorption and gel strength
tests, durability of the new seal was expected to be better. This
was confirmed by the clinical study. The fact that the new seal
could easily be removed in one piece, leaving no, few, or very few
residues, also support a high durability with low erosion and
dissolving during wear.
[0099] An interesting observation is the very good evaluation on
durability by both users with colostomy and urostomy. A urostomy
produces a large amount of fluidly out-put (urine) which
potentially may erode the adhesive more easily. Adding to this,
many users with an ileostomy, which also produces high amounts of
liquid output containing enzymes, also evaluated a high durability
of the seal.
[0100] In conclusion, users preferred the new Brava.RTM. Protective
Seal over their usual seal. The new seal was preferred,
particularly, because it left fewer residues on fingers and on
stomach. Further, it was evaluated to be very durable, and more so
compared to usual seal. In relation to easiness of appliance
change, users also evaluated the seal to be easy to handle, apply,
and remove, and easy to clean away from the peristomal skin.
[0101] The clinical study thus confirmed the hypothesized link
between striking a balance between gel strength and absorption and
achieving beneficial properties, durability in particular, in an
actual use situation.
* * * * *