GB2428381A

GB2428381A - Improved adhesive pads for ostomy bags

Info

Publication number: GB2428381A
Application number: GB0512036A
Authority: GB
Inventors: Rory Smith; Barry Mills
Original assignee: Welland Medical Ltd
Current assignee: Welland Medical Ltd
Priority date: 2005-06-14
Filing date: 2005-06-14
Publication date: 2007-01-31
Also published as: GB0512036D0

Abstract

A deformable pad 3 for removably securing an ostomy bag to the patient comprises a plastics film bonded to an adhesive layer and an opening 7 for receiving stomal waste. Preferably the opening is surrounded by a pliable continuously curvilinear formation 5 on the bodyside face of the pad. In a particular embodiment the curvilinear formation is dome shaped and may not be reinforced. In an alternative embodiment the pad formation may be reinforced by a hot melt adhesive applied to one surface of the pad. The bodyside of the pad may be covered by a release liner 15 preferably made from a plastics film and preformed to conform to the shape of the bodyside surface of the pad. The adhesive layer may comprise a hydrocolloidal composition or a hydrogel adhesive. The hydorgel adhesive may be a water based polymer formed of a polymeric material. The polymeric material may be a polyacylamide gel.

Description

ImDroved Adhesive Pads for Ostomy Bags This invention relates to adhesive

pads for ostomy bags, and more especially one-piece and two-piece ostomy bags employing a shaped body attachment surface.

Background of the Invention

Ostomy bags, such as urostomy, ileostomy and colostomy bags, are used to collect bodily waste draining from a stomal opening in the patient's body wall. Ostomy bags can be secured to the patient by means * *. of a belt or strap, and/or adhesive, but more usually they are affixed to the patient by means of an adhesive flange which surrounds the stomal orifice. S... * S S

:. For many ostomy bag wearers, the stomal opening is sited in a recess in the body wall. This may be a consequence of patient weight gain after intestinal surgery or the particular surgery performed. In such cases it is preferable to use an ostomy bag appliance wherein the body contacting surface is substantially convex in shape in order that the skin surrounding the opening of the stoma is contacted and adhered to the adhesive surface of the appliance. Such ostomy bag devices have become known as "convexity" appliances.

In the past, "convexity" appliances have created a number of problems. Commonly, manufacture involves the use of injection moulded plastics to form a rigid and often inflexible convex body attachment piece.

Unfortunately, such products are not only expensive to make but have led to a range of patient complaints resulting from the pressure required to fix the device in place. These include inter a/ia, skin damage, such as ulceration and bruising, and general discomfort. Such devices are also difficult to attach to the body wall so that the stomal orifice is aligned with the opening in the ostomy bag. The rigid edge of the moulding in the region of the orifice can damage the stoma, or cause further physical discomfort.

Existing devices do not accommodate the full range of body movements, such as reaching and bending, and therefore can lead to a loss of adhesion between the device and the body. Even a small loss of adhesion can lead to leakage.

The devices disclosed in the Applicant's European Patent 1178766 : ** and British Patent Application 0421289.0 comprise a deformable pad having a hollow convex formation on a bodyside face of the pad. The convex formation is hollow and has a flattened portion with a concave *:::: cavity or frustoconical depression on the surface of the pad opposite to the bodyside surface, beneath the convex formation. Such devices have proved successful but still suffer from disadvantages when a small gap forms between the flattened surface of the device and the patient's skin during patient movement.

Therefore, the present invention seeks to provide an improved convexity appliance which is more comfortable, is easier to apply to the body wall, improves adhesion between the device and the body and is simple to manufacture. The present invention allows the pad to maintain good contact with a patient's skin at all times, including during patient movement.

Summary of the Invention

Accordingly, in one aspect, the invention provides a deformable pad for removably securing an ostomy bag to the skin of a patient consisting essentially of a plastics film bonded to an adhesive material; the pad having an opening for receiving stomal waste, the opening being surrounded by a pliable continuously curvilinear formation on a bodyside face of the pad.

Preferably, the continuously curvilinear formation is dome shaped.

The term "dome-shaped" is used to refer to a hemispherical shape or any segment of a sphere. A dome-shaped formation on a body side face of the pad allows the pad to effectively "roll" over a patient's skin and particularly the stomal orifice, at all times maintaining good contact between the device and the body during patient movement. * S. * . S

The dome-shaped formation may be un-reinforced. S...

The term "un-reinforced" as used herein means that there is no reinforcing element, for example formed of an injection moulded plastics material, which affords greater stiffness to the convex formation.

By avoiding the use of a separate, stiff reinforcing plastics component, the pad has the advantage that it can be easily manipulated when the patient applies the device to the stomal orifice. Furthermore, there are no stiff and unyielding edges which can cause discomfort, or lead to the dislodgement of the device, as the patient bends and turns.

Preferably, the dome-shaped formation is a hollow cavity.

Alternatively, the dome-shaped formation is reinforced by a hot melt adhesive applied on one surface of the pad.

By "adhesive" it is meant a hot melt adhesive which is provided in molten form and solidifies on cooling. The dome-shaped formation results in improved adhesion for deformable pads of different shapes. For example, that disclosed in the Applicant's earlier British Patent Application No. 0421289.0, which is incorporated herein by reference.

The bodyside surface of the deformable pad may be covered or coverable with a release liner which may be made of a moulded plastics film. The release liner preferably conforms to the shape of the bodyside surface of the pad. The liner may be pre-formed eg by vacuum forming, but more preferably it is vacuum formed as a laminate together with the adhesive layer. The liner may be made from styrene, polyethylene, or PVC, eg high density or medium density. The liner can be coated with a silicone on one or both sides. * ** * S S

The continuously curvilinear, dome-shaped formation can be formed by deforming a combination of a layer of plastics film and *::: adhesive material and optionally a release liner layer in or on a suitably shaped mould. For example the layers can be moulded by thermo- forming in a one or two stage process. In the two stage process the :.. layers are initially cold-formed to form the required shape and then thermally treated to bond the layers together. In this embodiment, a dome- shaped cavity is formed on the surface of the pad opposite to the bodyside surface.

Alternatively, and more preferably, the continuously curvilinear, domeshaped formation can be formed by preparing a laminate comprising the layer of plastics film or a precursor thereof, the adhesive material, and a release liner as hereinbefore defined, and vacuum forming the laminate on a vacuum forming mould to provide the dome-shaped formation.

An advantage of forming a laminate comprising the release liner and then deforming the laminate is that the liner remains in intimate contact with the adhesive throughout the deforming process, and subsequently during storage. This prevents the formation of air bubbles or air pockets between the release liner and the adhesive, a problem inherent in many prior art adhesive pads, and which can cause drying out and loss of adhesive properties of the adhesive material.

Preferably, the adhesive material comprises a hydrocolloid composition or a hydrogel adhesive. The hydrogel adhesive may be an adhesive waterswellabje polymer. Preferably, the hydrogel adhesive is formed of polymeric materials which are cross-linked, either physically or chemically, for example, cross-linked polyacrylamide gels, polymers containing cross-linked polymer chains derived from styrene, isoprene, : *, cyclopentadiene and dioctyl adipate monomers, or polyhydroxyethylmethacrylic acids.

The hydrocolloid composition may comprise gel-forming natural and modified polysaccharides in combination with polymers based on styrene, : isoprene or isobutylene. S.. S

The plastics film is typically a thin film which is preferably less than 0.2 mm in thickness. Typically, the film comprises polyethylene. The film may be formed by heat treatment of a layer of woven or non-woven material, eg non-woven polyethylene.

The deformable pad may be of any shape suitable for use in a stomal appliance context. For example, the pad may take the form of a circular annulus or an oval shape.

The deformable pad may be of generally uniform thickness.

Alternatively, the pad may vary in thickness across its width, for example, it may decrease in thickness in a radially outward direction.

The adhesive material may have incorporated therein a reinforcing fabric such as a woven, knitted, or non-woven fabric.

In one embodiment, the side of the deformable pad opposite to the bodyside surface may be bonded to a backing layer which may be formed of a water-vapour permeable material, eg non-woven or spun-bonded material comprising polyethylene. The backing layer may extend radially beyond the adhesive material, and may be provided with an adhesive to enable it in use, to adhere to and form a seal against the skin of a patient radially outwardly of the deformable pad.

The adhesive may extend around the periphery of the backing layer and/or be interposed between the deformable pad and the backing layer S...

to bond the adhesive material thereto. * S S S. *

Preferably, the adhesive is a hypoallergenic adhesive which does not cause undue skin irritation.

* * The backing layer typically may be secured to an ostomy appliance such as an ostomy bag by, for example, adhesive bonding or welding, eg rf welding.

In yet another aspect, the invention provides an ostomy bag comprising a deformable pad for removably securing the bag to the skin of a patient about a stomal orifice, the deformable pad being as defined hereinabove.

The ostomy device may be either a one-piece or two-piece ostomy device. The two-piece ostomy device may comprise a two-part coupling having bodyside and bagside elements, the deformable pad being bonded to the bodyside element.

The invention will now be described by way of example only by reference to the accompanying diagrammatic drawings in which:- Figure 1 shows a partial side elevation of a deformable pad according to a first embodiment of the invention; Figure 2 shows a partial side elevation of a deformable pad according to a second embodiment of the invention.

Referring now to Figure 1, a deformable pad 1 according to the invention can comprise an adhesive pad 3, having a dome shaped formation 5. The dome shaped formation 5 is not flattened at the top. The : *. adhesive pad 3 is formed of a thin plastics layer such as non-woven polyethylene, bonded to the bagside surface of a layer of hydrocolloid adhesive material such as a polyisobutylene containing modified *:::: polysaccharides. The adhesive pad is provided with a generally central * aperture 7 through which the stoma of the patient may protrude. ***

Overlying the adhesive pad 3 is a backing layer 9 formed of polyethylene non-woven material. *

* Extending around the periphery of the backing layer 9 is a layer of adhesive 11, for example formed from an emulsion acrylic adhesive. As can be seen from the Figure, the backing layer 9 is provided with a portion 13 which extends radially beyond the adhesive pad.

The bodyside surface of the adhesive material is temporarily covered and protected by the use of a release liner 15 made of a moulded plastics film (eg polyethylene terephthalate (PET)) which can be removed immediately prior to use of the adhesive pad.

The surface of the backing layer which is opposite to the bodyside surface of the pad is typically bonded to an ostomy appliance such as an ostomy bag, for example by means of adhesive or by welding. For the purposes of clarity, the ostomy bag is not illustrated.

In use, the adhesive pad, with or without the ostomy appliance attached, is affixed to the skin of the patient about the stomal opening, the hydrocolloid adhesive serving to efficiently adhere the dome-shaped formation and the remainder of the pad to the skin of the patient.

Portions of the backing layer 9 form a seal against the skin by virtue of adhesive.

In one embodiment the deformable pad is produced using a heat and pressure die. A layer of thin plastics film, in this example, a layer of non-woven polyethylene, is place adjacent to a layer of hydrocolloid adhesive material. The hydrocolloid adhesive layer is laced on a release liner which is made of pre-formed, silicone-coated, PET. The three layers : * are positioned on the receiving surface of a dome shaped surface of one half of a moulding die in a hydraulic press such that the release liner is in contact with the surface of the die. The surfaces of the die are maintained a:::': at a temperature of 150 C. The hydraulic press brings the two halves of :. the moulding die together such that they exert a pressure of 2 bar on the layers which are thus bonded and shaped together. The heat and the pressure fuse the non-woven polyethylene material to form a shaped film which is bonded to the hydrocolloid adhesive material to give it form.

a'.... * a

Typically, the moulding die exerts a pressure from about 1 to 3 bar on the layers which form the pad. Preferably, the tooling is maintained at a temperature of between about 100 C and 200 C. The exact pressure and temperature required depends on the materials chosen to form the deformable pad.

Alternatively the deformable pad is produced by vacuum forming.

The deformable pad comprises a release liner layer, an adhesive layer and a backing layer. The release layer, adhesive pad and backing layer being formed from the same materials as described above in relation to Figure 1. By way of example, the release liner can be from about 180 microns thick, the hydrocolloid adhesive layer can be from 0.9 mm to 1.2 mm thick, and the non-woven layer backing layer can be approximately 0.2 to 0.6 mm thick, more preferably 0.3 mm thick.

The three layers are initially laminated together using an extrusion and laminating line and are then cut to the desired shape. Typically the blank thus formed is of a generally circular shape, but with one or more part-circular tab portions being provided around the periphery of the circle to facilitate fixing and removal of the adhesive pad to and from the patient. The release liner typically is formed with a hole at the centre thereof, although it need not be.

The planar laminate blank is then placed on a vacuum forming machine, the moulding tool having a dome-shaped form. A means of heating, such as a radiant heater, is positioned above the laminating machine in order to soften the laminate, and the laminate is then : ", subjected to vacuum forming for a period of, for example, five to seven seconds. The dome-shaped laminate can then be removed from the mould and secured to an ostomy bag in accordance with methods known perse.

A major advantage of the adhesive pad formed in accordance with the vacuum forming method as described above is that it prevents the formation of air bubbles or air pockets between the release liner and the adhesive layer, a problem which afflicts many known adhesive pads.

Consequently, the adhesive pad of the invention does not suffer from the problems of excessive drying out, and the consequent loss of adhesive properties, experienced with many known ostomy pads.

It will be understood that the foregoing is merely exemplary of an embodiment of the invention and that modification may be made without departing from the true scope of the invention as defined in the accompanying claims.

Claims

* 0 lIt * *S* S S S * S * I I * 0 S S I IS * S Ill ISO S I S S * * S * S I

* S * . S S * Claims 1. A deformable pad for removably securing an ostomy bag to the skin of a patient comprising a plastics film bonded to an adhesive material; the pad having an opening for receiving stomal waste and the opening being surrounded by a pliable continuously curvilinear formation on a bodyside face of the pad.
2. A deformable pad according to claim 1 wherein the continuously curvilinear formation is dome shaped.
3. A deformable pad according to claim 1 or claim 2 wherein the continuously curvilinear formation is un-reinforced.
4. A deformable pad according to any one of the preceding claims wherein the continuously curvilinear formation is a hollow cavity.
5. A deformable pad according to claim 1 or claim 2 wherein the continuously curvilinear formation is reinforced by a hot melt adhesive applied on one surface of the pad.
6. A deformable pad according to any one of the preceding claims wherein a bodyside surface of the deformable pad is covered or coverable with a release liner.
7. A deformable pad according to claim 6 wherein the release liner is made of a moulded plastics film.
8. A deformable pad according to claim 6 or claim 7 wherein the release liner conforms to the shape of the bodyside surface of the pad.
9. A deformable pad according to any one of claims 6 to 8 wherein the release liner is pre-formed.

* S $15 * 5$.

* S * * I S * S I * S I S S IS * : : : : : * : * . . .
10. A deformable pad according to any one of claims 6 to 9 wherein the release liner is vacuum formed.
11. A deformable pad according to claim 10 wherein the release liner is vacuum formed as a laminate together with an adhesive layer.
12. A deformable pad according to any one of claims 6 to 11 wherein the release liner may is made from any one of styrene, polyethylene, or PVC.
13. A deformable pad according to claim 12 wherein the release liner is made of high density or medium density PVC.
14. A deformable pad according to any one of claims 6 to 13 wherein the release liner is coated with a silicone on at least one side.
15. A deformable pad according to any one of the preceding claims wherein the continuously curvilinear formation is formed by deforming a combination of a layer of plastics film and a layer of adhesive material on a suitably shaped mould.
16. A deformable pad according to claim 15 wherein the continuously curvilinear formation further comprises a release liner layer.
17. A deformable pad according to any one of claim 15 or claim 16 wherein the layers are moulded by thermo-forming in a one-stage process.
18. A deformable pad according to any one of claim 15 or claim 16 wherein the layers are moulded by thermo-forming in a two-stage process.

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19. A deformable pad according to claim 18 wherein the layers are initially cold-formed to form the required shape and then thermally treated to bond the layers together.
20. A deformable pad according to claim 19 wherein the continuously curvilinear formation is formed on a surface of the pad opposite to a bodyside surface.
21. A deformable pad according to claims 1 to 16 wherein the continuously curvilinear formation is formed by preparing a laminate comprising a layer of plastics film or a precursor thereof, a layer of adhesive material, a release liner, and vacuum forming the laminate on a vacuum forming mould to provide the continuously curvilinear formation.
22. A deformable pad according to any one of claims 15 to 21 wherein the adhesive material comprises a hydrocolloid composition or a hydrogel adhesive.
23. A deformable pad according to claim 22 wherein the hydrogel adhesive is a water-soluble polymer.
24. A deformable pad according to claim 22 or claim 23 wherein the hydrogel adhesive is formed of a polymeric material which is crosslinked.
25. A deformable pad according to claim 24 wherein the polymeric material is any of; a cross-linked polyacrylamide gel, a polymer containing crosslinked polymer chains derived from styrene, isoprene, * . *.* . I..

* I I * I * * I I * I I * I II * * III *IS S S * S * I S * I * * S * * S I * cyclopentadiene and dioctyl adipate monomers or polyhydroxyethylmethacrylic acids; or a hydrocolloid composition comprising gel-forming natural and modified polysaccharjdes in combination with polymers based on styrene, isoprene or isobutylene.
26. A deformable pad according to claims 15 to 25 wherein the plastics film is a thin film.
27. A deformable pad according to claim 26 wherein the thin film is less than 0.2 mm in thickness.
28. A deformable pad according to claims 15 to 27 wherein the film comprises polyethylene.
29. A deformable pad according to claims 15 to 28 wherein the film is formed by heat treatment of a layer of woven or non-woven material, such as non-woven polyethylene.
30. A deformable pad according to any preceding claim shaped to be suitable for use in a stomal appliance context.
31. A deformable pad according to any preceding claim wherein the pad is in the form of a circular annulus.
32. A deformable pad according to any one of claims 1 to 30 wherein the pad is oval shaped.
33. A deformable pad according to any one of the preceding claims wherein the deformable pad is of uniform thickness.

* I *.I * SI.

* . S S S S S * I I I I * I S IS * S 555 SS* S S * * S S S S S S S * S * S S
34. A deformable pad according to any one of claims 1 to 32 wherein the deformable pad varies in thickness across its width.
35. A deformable pad according to claim 34 wherein the deformable pad decreases in thickness in a radially outward direction.
36. A deformable pad according to any one of claims 15 to 35 wherein a reinforcing fabric such as a woven, knitted, or non-woven fabric is incorporated into the adhesive material.
37. A deformable pad according to any of the preceding claims wherein a side of the deformable pad opposite to a bodyside surface is bonded to a backing layer.
38. A deformable pad according to claim 37 wherein the backing layer is formed of a water-vapour permeable material.
39 A deformable pad according to claim 38 wherein the water-vapour permeable material is a non-woven or spun-bonded material comprising polyethylene.
40. A deformable pad according to claims 37 to 39 wherein the backing layer extends radially beyond the adhesive material, and the pad further comprises an adhesive to enable the pad, in use, to adhere to and form a seal against the skin of a patient radially outwardly of the deformable pad.
41. A deformable pad according to claims 37 to 40 wherein the adhesive extends around the periphery of the backing layer and/or is interposed between the deformable pad and the backing layer to bond the adhesive material thereto.

* * *** . ** * S * S S S S * * S S S S S * *S * S III **S I * S * S I S * I S * * S I S S
42. A deformable pad according to any one of claims 15 to 41 wherein the adhesive is a hypoallergenic adhesive.
43. A deformable pad according to any one of claims 37 to 42 wherein the backing layer is secured to an ostomy appliance such as an ostomy bag.
44. A deformable pad according to claim 43 wherein the backing layer is secured to the ostomy appliance by adhesive bonding or welding including rf welding.
45. An ostomy bag comprising a deformable pad as claimed in any one of the preceding claims for removably securing the bag to the skin of a patient about a stomal orifice.
46. An ostomy bag as claimed in claim 45 wherein the ostomy bag is a onepiece ostomy device.
47. An ostomy bag as claimed in claim 45 wherein the ostomy bag is a twopiece device.
48. An ostomy bag as claimed in claim 47 comprising a two-part coupling having bodyside and bagside elements wherein the deformable pad is bonded to the bodyside element.
49. A deformable pad substantially as hereinbefore described or referred to in Figures 1 or 2.