WO2025253099A1

WO2025253099A1 - Ostomy appliance

Info

Publication number: WO2025253099A1
Application number: PCT/GB2025/051195
Authority: WO
Inventors: Jennifer Evans; Oliver PFLEGER
Original assignee: Convatec Ltd
Current assignee: Convatec Ltd
Priority date: 2024-06-03
Filing date: 2025-06-02
Publication date: 2025-12-11
Anticipated expiration: 2026-12-03

Abstract

An ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use; and a support membrane bonded to the baseplate and to a coupling component for attaching to a fluid collection pouch.

Description

OSTOMY APPLIANCE

Technical Field of the Invention

The present invention relates to an ostomy appliance, in particular to an ostomy baseplate to be worn on the body of an ostomate and which may be coupled to a pouch for collecting effluent.

Background to the Invention

The present disclosure relates to devices that attach to a patient's body after they have undergone a surgical ostomy procedure, typically to address a problem with their gastrointestinal tract. The varied problems they experience interfere with their body's normal processes for processing and collecting the waste products from the digestive processes. Ostomates, as these patients are referred to, are typically required to wear and maintain these waste-collection devices for significant portions of their life, if not for the remainder of their life. Typically, teh devices are comprised of an adhesive “doughnut” surrounding the stoma's exit from their abdomen. The adhesive adheres to the patient on one side and to a baseplate on the other. The baseplate typically comprises a coupling ring comprising means for releasable attachment of an effluent collection bag or pouch. The system is intended during operation to provide a liquid and reasonably gas-tight seal so the ostomate can enjoy an active and socially engaged life.

The forces required to decouple and recouple the fluid collection pouch to the coupling ring are typically reacted directly back against the patient's abdomen. Many ostomates experience discomfort as a result of an attachment force applied through the ostomy appliance to the skin, when two coupling parts are pressed together. The problem of discomfort is especially important during post-operative care, when the stoma surgery is recent and the abdominal skin is very tender.

To reduce the discomfort experienced by ostomates, it is known to provide a support membrane secured between the baseplate and the coupling ring. In the art, a support membrane and coupling ring are often referred to as a ‘floating coupling part’. The support membrane allows the coupling component to be displaced away from the baseplate by a sufficient amount such that a user can insert one or more fingers behind the coupling component, in order to manually support the coupling component against the force of attaching the fluid collection pouch to the coupling component. Displacing the coupling component away from the user also allows the user to support the coupling component and, possibly, fluid collection pouch, whn the appliance is pressed against the body. However, there remains a need to further reduce the discomfort experienced by ostomates when attaching the fluid collection pouch to the coupling component, and when pressing the appliance against the ostomate’s body.

Further, while the use of a support membrane may provide a reduction in transmission of the attachment force to the abdominal skin, there are several disadvantages of this known type of coupling which are increasingly apparent when such known appliances are used in everyday life.

For example, the support membrane is typically attached to an inner surface of the baseplate at a substantially flat surface which surrounds an aperture in the baseplate, such aperture being arranged in line with the ostomate’s stoma to allow the flow of effluent from the ostomate’s abdomen, through the stoma and into the fluid collection pouch. As such, in the prior art, the bonding surface of the support membrane to the inner surface of the baseplate is typically in the same plane as the aperture. Disadvantageously, such an arrangement limits the diameter of the aperture in the baseplate which in turn restricts the size of stoma with which the ostomy appliance may be used.

Further, an important consideration in the design of ostomy appliances is the need for an appliance which provides a small baseplate footprint and low height profile upon the ostomate’s body. Disadvantageously, in appliances comprising a support membrane attached to the substantially planar portion of the baseplate, the footprint and overall height profile of the ostomy appliance is relatively large. This is typically due to the need to provide a planar surface for bonding to the support membrane, which in turn requires the baseplate to have a depth which is substantially equal to the overall height of the ostomy appliance, so as to provide a planar surface distal to the stoma, to which a support membrane and, therefore, a coupling component for attachment to a pouch, can be bonded. This is particularly disadvantageous for ostomates with a relatively smaller physique as the ostomy appliance may be more prominent when worn, compared to ostomate’ s with a relatively larger physique. Generally, this also results in an appliance which is not as discreet as is desired by ostomates.

Further, a baseplate, which is typically formed of a relatively stiff plastic material, having a depth which is substantially equal to the overall height of the ostomy appliance, means that the ostomy appliances of the prior art comprising such a baseplate are relatively stiff and provide little flexibility to the ostomate when being worn. The relatively inflexible ostomy appliance can be uncomfortable for the wearer and may be a hindrance to the wearer in carrying out day-to-day tasks or any physical activity.

Moreover, disadvantageously, especially in known ostomy appliances comprising a support membrane, there is a tendency for the fluid collection pouch to sag away from the baseplate, in particular when teh pouch holds a significant amount of effluent. This is because the support membrane is provided to allow the pouch to be displaced away from the baseplate. It is possible to increase the stiffness of the support membrane, in order to reduce such sagging and maintain a low profile, but the stiffer the support membrane, the greater is the force that the ostomate has to apply to displace the coupling component away from the baseplate, and to maintain the coupling component in the displaced position. This can be inconvenient for the ostomate, especially elderly ostomates or ostomates with limited dexterity. Further, at least some of the increased force applied to the coupling component when displacing it away from the baseplate and maintaining it in such a displaced position, will inevitably be transmitted to the underlying tender abdominal skin, therefore, increasing the risk of discomfort instead of reducing discomfort.

For the ostomate, sagging of the fluid collection pouch presents a significant problem as the ability to wear an ostomy appliance discreetly, which is considerably valued by an ostomate, is often negated once the pouch starts to sag away from the baseplate.

It is an object of embodiments of th present invention to at least partially overcome or alleviate the above problems and/or to provide an improved ostomy appliance. Summary of the Invention

The present invention concerns an ostomy appliance. The ostomy appliance may comprise a baseplate. The baseplate may comprise an aperture therein to permit the passage of effluent therethrough. The aperture may have a plane perpendicular to the axis through which effluent flows in use. The baseplate may comprise an outer surface which faces an ostomate in use. The outer surface may be angled with respect to the plane of the aperture. The baseplate may comprise an inner surface angled with respect to the plane of the aperture. The ostomy appliance may comprise a support membrane. The support membrane may be bonded to the baseplate. The support membrane may be bonded to a coupling component. The coupling component may be for attaching to a pouch. The support membrane may be bonded to the angled inner surface of the baseplate.

Accordingly in a first aspect of the invention, there is provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; a support membrane bonded to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane is bonded to the angled inner surface of the baseplate.

The present invention provides an ostomy appliance which benefits from the support membrane being bonded to the angled inner surface of the baseplate. Comparatively, arrangements of the prior art typically require the support membrane to be bonded to a substantially flat surface which surrounds an aperture in the baseplate, and which affords a bonding surface which is in the same plane as that of the aperture in the baseplate. Advantageously, in the present invention, a support membrane bonded to an angled inner surface of the baseplate means that the bonding surface of the support membrane to the inner surface of the baseplate is not proximal to the aperture in the baseplate. Thus, the bonding surface of the support membrane to the inner surface of the baseplate is not restrictive upon the diameter of the aperture in the baseplate. As such, an ostomy appliance of the present invention may comprise a baseplate comprising an aperture which is of greater diameter than the same, or similarly sized, ostomy appliances found in the prior art. Thus, it follows that, advantageously, ostomy appliances of the present invention may be manufactured comprising an aperture of various diameters to suit the accommodate specific customer preferences for postoperative care, and also different customer preferences for everyday use. The ostomy appliance of the present invention finds applicability with various sizes of stomas meaning that the ostomy appliance of the invention can be used with a greater number of ostomates compared to many ostomy appliances of the prior art.

In addition, the present invention benefits from the support membrane being bonded to the angled inner surface of the baseplate, not least because this arrangement reduces the pressure applied directly onto the abdomen of the ostomate. In particular, the present arrangement avoids the application of significant pressure in an area proximal to the ostomate’ s stoma as is found in the prior art due to a support membrane typically being bonded to the baseplate proximal to the aperture in the baseplate. Advantageously, the support membrane bonded to the angled inner surface of the baseplate, as in the present invention, dissipates a portion of the pressure applied to the baseplate, away from the aperture in the baseplate and, therefore, away from the stoma, meaning the ostomate can move the coupling component between retracted and extended positions with greater comfort.

The ostomy appliance of the invention also finds benefit compared with ostomate appliances of the prior art which comprise a support membrane attached to a substantially planar peripheral portion of the baseplate, arranged distal from the aperture in the baseplate.

Advantageously, in the present invention, the support membrane is bonded to the angled inner surface of the baseplate. As such, the diameter of the support membrane and, therefore, the coupling component can be smaller compared to the diameter of a support membrane and coupling component which are found in ostomy appliances of the prior art where the support membrane is bonded to a peripheral portion of the baseplate. Advantageously, this reduces the footprint of the baseplate, which is significantly favourable for ostomates with a relatively small physique, and increases overall flexibility of the ostomy appliance, which is advantageous with regard to the ostomy appliance being able to be securely fitted to an ostomate’s body.

Moreover, the smaller footprint of the baseplate means that the ostomy appliance is more discreet compared to ostomy appliances of the prior art comprising a support membrane bonded to a peripheral portion of the baseplate distal to the aperture. Thus, the ostomy appliance of the present invention benefits from the advantages afforded by comprising a support membrane and does not suffer the drawbacks associated with ostomy appliances of the prior art having a comparably larger baseplate footprint and/or height profile of the ostomy appliance.

The present invention benefits from a relatively small baseplate footprint and low height profile compared to known ostomy appliances, such as those described herein. Bonding the support membrane to the angled inner surface of the baseplate means that there is no need to provide a planar surface, which is in the same plane as the aperture, of the baseplate for bonding to the support membrane. As such, the baseplate is not required to have a depth which is equal, or at least substantially equal, to the overall height of the ostomy appliance. As such, beneficially, the ostomy appliance of the present invention provides for a relatively small baseplate footprint and low height profile. Thus, the present invention is particularly suitable for ostomates having a relatively small physique as the prominence of the ostomy appliance is significantly reduced. Moreover, a substantial portion of the known baseplate which affords its depth is not found in the present invention. As such, the overall flexibility of the ostomy appliance of the present invention is greatly increased compared to the flexibility of similar ostomy appliances of the prior art. Advantageously, this means that the ostomy appliance of the present invention is more comfortable for the wearer and does not act as a hindrance to the wearer in carrying out day-to-day tasks or physical activity.

Further, as the baseplate of the present invention is not required to have a depth which is equal, or at least substantially equal, to the overall height of the ostomy appliance, significantly fewer materials, typically plastic materials, are required to form the baseplate of the present invention compared to a baseplate of similar, known ostomy appliances. As such, manufacture of the present invention is environmentally favourable compared to the manufacture of similar ostomy appliances of the prior art.

The angled inner surface of the baseplate may be flat, or at least substantially flat. Beneficially, a flat, or at least substantially flat, angled inner surface of the baseplate may allow for a greater bond between the support membrane and the angled inner surface of the baseplate, in particular if the bond between the support membrane and the angled inner surface of the baseplate is formed by heat-welding or laserbonding.

In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; a support membrane bonded to the baseplate and to a coupling component for attaching to a fluid collection pouch; wherein the support membrane is bonded to the angled inner surface of the baseplate, further wherein the angled inner surface of the baseplate is flat, or at least substantially flat.

In embodiments where the support membrane is bonded to the angled inner surface of the baseplate by laser-bonding, advantageously the method comprises less tooling changeover during manufacture. Further advantageously, a weld path of the laser can be more easily tailored to different geometries of the baseplate compared to a weld path formed by, for example, heat-welding or ultrasonic welding.

The angled inner surface of the baseplate may be concave with respect to the plane of the aperture. Beneficially, a baseplate comprising an angled inner surface which is concave with respect to the plane of the aperture provides for processing and manufacturing advantages, for example the baseplate may be easier to form by injection moulding due to a uniform thickness of the wall of the baseplate which comprises the angled inner surface.

In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; a support membrane bonded to the baseplate and to a coupling component for attaching to a fluid collection pouch; wherein the support membrane is bonded to the angled inner surface of the baseplate, further wherein the angled inner surface of the baseplate is concave with respect to the plane of the aperture.

The angled inner surface of the baseplate may comprise a flat, or at least substantially flat, portion to which the support membrane is bonded.

The angled inner surface of the baseplate may comprise a flat, or at least substantially flat, portion and a curved portion which is concave relative to the plane of the aperture, and in which the support membrane is bonded to the flat, or at least substantially flat, portion.

The angled inner surface of the baseplate may comprise a flat, or at least substantially flat, portion and a curved portion which is concave relative to the plane of the aperture, and in which the support membrane is bonded to the flat, or at least substantially flat, portion and is not bonded to the curved portion.

The angled inner surface of the baseplate may be at an angle of from about 10° to about 80°, from about 15° to about 75°, from about 20° to about 70°, from about 25° to about 65°, from about 30° to about 60°, from about 35° to about 55°, from about 40° to about 50°, or about 45°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 10° to about 80°, from about 10° to about 75°, from about 10° to about 70°, from about 10° to about 65°, from about 10° to about 60°, from about 10° to about 55°, from about 10° to about 50°, from about 10° to about 45°, from about 10° to about 40°, from about 10° to about 35°, from about 10° to about 30°, from about 10° to about 25°, from about 10° to about 20°, or from about 10° to about 15°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 15° to about 80°, from about 15° to about 75°, from about 15° to about 70°, from about 15° to about 65°, from about 15° to about 60°, from about 15° to about 55°, from about 15° t 50°, from about 15° to about 45°, from about 15° to about 40°, from about 15°t 35°, from about 15° to about 30°, from about 15° to about 25°, or from aboutbout 20°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 20°t 70°, from about 20° to about 65°, from about 20° to about 60°, from about 20°t 55°, from about 20° to about 50°, from about 20° to about 45°, from about 20°t 40°, from about 20° to about 35°, from about 20° to about 30°, or from aboutbout 25°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 25°t 70°, from about 25° to about 65°, from about 25° to about 60°, from about 25°t 55°, from about 25° to about 50°, from about 25° to about 45°, from about 25°t 40°, from about 25° to about 35°, or from about 25° to about 30°, with respectlane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 30°t 70°, from about 30° to about 65°, from about 30° to about 60°, from about 30°t 55°, from about 30° to about 50°, from about 30° to about 45°, from about 30°t 40°, or from about 30° to about 35°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 35°t 70°, from about 35° to about 65°, from about 35° to about 60°, from about 35°t 55°, from about 35° to about 50°, from about 35° to about 45°, or from aboutbout 40°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 40°t 70°, from about 40° to about 65°, from about 40° to about 60°, from about 40°t 55°, from about 40° to about 50°, or from about 40° to about 45°, with respectlane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 45°t 70°, from about 45° to about 65°, from about 45° to about 60°, from about 45°t 55°, or from about 45° to about 50°, with respect to the plane of the aperture. The angled inner surface of the baseplate may be at an angle of from about 50° to about 70°, from about 50° to about 65°, from about 50° to about 60°, or from about 50° to about 55°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 55° to about 70°, from about 55° to about 65°, or from about 55° to about 60°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 60° to about 70°, or from about 60° to about 65°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of from about 65° to about 70°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of about 10°, about 15°, about 16°, about 18°, about 20°, about 22°, about 24°, about 25°, about 26°, about 28°, about 30°, about 32°, about 34°, about 35°, about 36°, about 38°, about 40°, about 42°, about 44°, about 45°, about 46°, about 48°, about 50°, about 52°, about 54°, about 55°, about 56°, about 58°, about 60°, about 62°, about 64°, about 65°, about 66°, about 68°, or about 70°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of at least about 10°, about 15°, about 16°, about 18°, about 20°, about 22°, about 24°, about 25°, about 26°, about 28°, about 30°, about 32°, about 34°, about 35°, about 36°, about 38°, about 40°, about 42°, about 44°, about 45°, about 46°, about 48°, about 50°, about 52°, about 54°, about 55°, about 56°, about 58°, about 60°, about 62°, about 64°, about 65°, about 66°, about 68°, or at least about 70°, with respect to the plane of the aperture.

The angled inner surface of the baseplate may be at an angle of no more than about 10°, about 15°, about 16°, about 18°, about 20°, about 22°, about 24°, about 25°, about 26°, about 28°, about 30°, about 32°, about 34°, about 35°, about 36°, about 38°, about 40°, about 42°, about 44°, about 45°, about 46°, about 48°, about 50°, about 52°, about 54°, about 55°, about 56°, about 58°, about 60°, about 62°, about 64°, about 65°, about 66°, about 68°, or no more than about 70°, with respect to the plane of the aperture. In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; a support membrane bonded to the baseplate and to a coupling component for attaching to a fluid collection pouch; wherein the support membrane is bonded to the angled inner surface of the baseplate, further wherein the angled inner surface of the baseplate is at an angle of from about 10° to about 60° with respect to the plane of the aperture.

The support membrane may be formed of a plastic film. The plastic film may be resiliently stretchable, or it may be substantially non- stretchable. Suitable plastic films include, for example, ethylene vinyl acetate copolymer (EVA), polyethylene (PE) or metalocene film. The plastic film may have a thickness of between 0.05 mm and 0.50 mm.

The support membrane may have two stable positions. As such, the support membrane may have bistable positions. The support membrane may have at least two stable positions. For example, the support membrane may have two, three, four, five, six, or more, stable positions.

In embodiments comprising a support membrane having bistable positions, the bistable positions may be a retracted position and an extended position.

In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; a support membrane bonded to the baseplate and to a coupling component for attaching to a fluid collection pouch; wherein the support membrane is bonded to the angled inner surface of the baseplate, further wherein the support membrane has bistable positions. The support membrane may be configured to allow the coupling component to transition between the retracted position and the extended position. The support membrane may be configured to hold itself stably in each of the retracted position and the extended position. The support membrane may be configured to hold itself stably in each of the retracted position and the extended position by means of internal stress in the material of the support membrane.

In the retracted position, the support membrane may hold the coupling component to bear directly or indirectly against the baseplate. As such, in the retracted position, the coupling component may be held close to the baseplate which prevents, or at least resists, sagging of the support membrane, coupling component and the pouch. Moreover, in the retracted position, the ostomy appliance, in particular the support membrane and coupling component, maintains a low profile height. This is favourable for the ostomate, not least because in the retracted position, the ostomy appliance maintains a discreet profile.

In the extended position, the coupling component may be displaced away from the baseplate. Advantageously, in the extended position, the support membrane can hold the coupling component spaced from the baseplate, without any pulling force required to be maintained upon the underlying skin which may be uncomfortable to the ostomate.

The support membrane may comprise a through passage. The through passage may provide a passage for effluent entering the ostomy appliance from a stoma. The effluent moves from the stoma, through the aperture in the baseplate, along the through passage of the support membrane, and into the fluid collection pouch.

The support membrane may comprise a first interface region. The first interface region may be connected to the coupling component.

The support membrane may comprise a second interface region. The second interface region may be bonded to the angled inner surface of the baseplate.

In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; a support membrane bonded to the baseplate and to a coupling component for attaching to a fluid collection pouch; wherein the support membrane is bonded to the angled inner surface of the baseplate, further wherein the support membrane comprises a first interface region connected to the coupling component, and the support membrane comprises a second interface region bonded to the angled inner surface of the baseplate.

In embodiments comprising a support membrane having retracted and extended bistable positions, and having a first interface region and a second interface region, the support membrane may be configured to hold the coupling component stably in, (i) the extended position in which the first and second interface regions are substantially spaced apart in an axial direction of the through passage, and (ii) in the retracted position in which the first and second interface regions are positioned closer together in the axial direction. In the retracted position, the first and second interface regions may bear directly or indirectly against one another, or may bear in proximity to one another.

In the extended position, the ostomy appliance may comprise an annular space between the coupling component and the baseplate. The annular space may be configured to allow an ostomate to manually brace the coupling component when fitting the pouch. Thus, in the extended position, the ostomate can manually brace the coupling component in and around the first interface region, which is spaced apart from the second interface region and, therefore, spaced away from the baseplate. As such, the ostomate can couple and decouple the pouch from the coupling component without needing to apply pressure to the baseplate or the underlying skin proximal to the stoma that may be uncomfortable to the ostomate.

The support membrane may have a configuration selected as one or more of: (i) an extended tube when in the extended position, (ii) a folded tube when in the retracted position. When in the extended position, the extended tube may provide a through passage for effluent. The support membrane may comprise at least one foldable portion. The at least one foldable portion may comprise one or more tubular segments that meet at one or more fold points, such that one tubular segment may invert to nest within another tubular segment when the support membrane is in the retracted position. The support membrane may be formed of a flexible material which, in combination with the one or more fold points, may allow overcentering movement between the bistable positions.

The support membrane may be pleated when in the retracted position. The pleated support membrane may comprise one, two, three, four, five, or more, folds.

The support membrane may be bonded to the angled inner surface of the baseplate by heat-welding, laser-bonding, ultrasonic welding or adhesive bonding.

The outer surface of the baseplate may comprise an adhesive layer. The adhesive layer may adhere the baseplate to the skin of the ostomate and create a strong adhesive connection suitable for carrying the weight of a pouch and its stomal output contents. The outer surface of the baseplate may comprise more than one adhesive layer. The outer surface of the baseplate may comprise a first adhesive and a second adhesive. The adhesive layer may be a peelable adhesive, such as an acrylate-based peelable adhesive.

The adhesive layer may comprise a hydrocolloid. The adhesive layer may comprise one or more different types of hydrocolloids. Using one or more hydrocolloids in the adhesive layer provides an adhesive with optimised moisture absorption capabilities.

Examples of hydrocolloids may include polysaccharides, such as starch, glycogen, hemicelluloses, pentosans, gelatin, celluloses, modified celluloses, pectin, chitosan, and chitin. Modified celluloses may include methyl cellulose, hydroxypropyl methyl cellulose, carboxymethylcellulose, and hydroxypropyl cellulose. The hydrocolloid may be a water soluble or swelling hydrocolloid chosen from the group consisting of polyvinyl alcohols, powdered pectin, gelatin, methyl cellulose, hydroxypropyl methyl cellulose, carboxymethyl cellulose, hydroxypropyl cellulose and mixtures thereof. The hydrocolloid may be carboxymethyl cellulose (CMC). The coupling component may have an outer diameter of about 40mm, about 45mm, about 50mm, about 55mm, about 60mm, about 65mm, about 70mm, about 75mm, about 80mm, about 85mm, about 90mm, about 95mm, or about 100mm.

The coupling component may have an outer diameter of no more than about 70mm, about 75mm, about 80mm, about 85mm, about 90mm, about 95mm, or no more than about 100mm. Advantageously, a support membrane bonded to an angled inner surface of the baseplate means that the diameter of the coupling component can be smaller compared with the diameter of coupling components comprised in ostomy appliances of the prior art in which a support membrane is bonded, for example, to a peripheral portion of the baseplate distal to the aperture. Further advantageously, this reduces the footprint of the baseplate, which is significantly favourable for ostomates with a relatively small physique, and increases overall flexibility of the ostomy appliance, which is advantageous with regard to the ostomy appliance being able to be securely fitted to an ostomate’s body.

The support membrane may be configured to transition between the retracted position and the extended position when a predetermined force is applied. The predetermined force may be in the axial direction of the support membrane. For example, to transition the support membrane from the retracted position to the extended position, an ostomate may be required to pull the support membrane away from their body. This causes the one or more fold points to straighten with relative ease due to the internal stresses of the material forming the support membrane. The ostomate may use the coupling component as a grip to pull the support membrane away from their body. The support membrane then assumes its extended position, providing an annular space between the coupling component and the baseplate for the ostomate to insert one or more fingers or one or both hands. Although the ostomate is required to apply an amount of force to transition the support membrane from the retracted position to the extended position, this force is required for a very short period of time to displace the coupling component away from the body. Once in the extended position, the ostomate is not required to maintain any pulling force on the ostomy appliance and, therefore, the underlying skin of the ostomate is relieved from discomfort which may otherwise be experienced by a pulling action upon the coupling component. Thus, advantageously, the coupling component remains in its stable, extended position without constant force needing to be applied by the ostomate.

To fit a pouch to the ostomy appliance, the ostomate then presses an attachment means comprised on the pouch into engagement with a corresponding attachment means comprised on the coupling component, while at the same time using their fingers to brace the coupling component so as to relieve the attachment force from being transmitted through the support membrane to the baseplate and, therefore, to the ostomate’ s skin.

Once the pouch has been fitted, the ostomate removes their fingers from the annular space and transitions the support membrane from the extended position to the retracted position. This may be achieved by gently pushing the coupling component toward the baseplate. The pushing action causes the one or more fold points to return to their folded state, such that the support membrane assumes its retracted position which in turn brings the coupling component into closer proximity to the baseplate. The stable shape of the support membrane in its retracted position resists sagging of the pouch and ostomy appliance away from the ostomate’ s body. Thus, advantageously, the ostomy appliance may be used for post-operative care and everyday use.

The at least one foldable portion may extend circumferentially around the aperture. The at least one foldable portion may be configured to allow the coupling component to transition between the retracted position and the extended position. The at least one foldable portion may have a variable height when in the extended position.

The support membrane may be bonded directly to the angled inner surface of the baseplate. Beneficially, this reduces the number of components composed in the ostomy appliance, therefore reducing cost of manufacturing the appliance and increasing simplicity of the appliance.

In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; a support membrane bonded to the baseplate and to a coupling component for attaching to a fluid collection pouch; wherein the support membrane is bonded to the angled inner surface of the baseplate, further wherein the support membrane is bonded directly to the angled inner surface of the baseplate.

The invention according to the first aspect may include any features, including optional features, of the invention according to any other aspect.

The invention also concerns an ostomy appliance. The ostomy appliance may comprise a baseplate. The baseplate may have an aperture therein to permit the passage of effluent therethrough. The ostomy appliance may comprise a support membrane. The support membrane may be bonded to the baseplate. The support membrane may be bonded to a coupling component for attaching to a pouch. The support membrane may comprise at least one foldable portion. The at least one foldable portion may extend circumferentially around the aperture. The at least one foldable portion may be configured to allow the coupling component to transition between a retracted position and an extended position. The at least one foldable portion may have a variable height when in the extended position.

Accordingly, in a second aspect of the invention, there is provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough; a support membrane bonded to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the at least one foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the at least one foldable portion has a variable height when in the extended position.

The invention provides an ostomy appliance which benefits from the support membrane comprising at least one foldable portion which extends circumferentially around the aperture, and which is configured to allow the coupling component to transition between a retracted position and an extended position, and in which the foldable portion has a variable height when in the extended position. Comparatively, ostomy appliances of the prior art comprise a support membrane comprising at least one foldable portion which extends around an aperture in a baseplate, the at least one foldable portion having a constant height when in the extended position. Such ostomy appliances of the prior art suffer from sagging, especially when the associated pouch contains a significant amount of effluent.

Advantageously, in the present invention, a support membrane comprising a foldable portion which has a variable height when in the extended position, means that sagging of the ostomy appliance is prevented, or at least significantly reduced, which significantly aids the discretion of wearing an ostomy appliance which is crucially desired by ostomates. This is achieved without needing to increase the stiffness of the support membrane, which is typically considered in the prior art as a means to reduce sagging. As such, without increasing the stiffness of the support membrane, there is no increase in the force required to be applied by an ostomate to displace the coupling component away from the baseplate. Thus, sagging is prevented, or at least reduced, without needing to impart properties to the support membrane which hinder use of the ostomy appliance by a user, in particular by elderly ostomates or those with limited dexterity, and which increases the risk of discomfort. As such, an ostomy appliance is provided which prevents, or at least reduces, sagging while not compromising its user’s comfort, convenience or discretion of using an ostomy appliance.

The aperture may have a plane perpendicular to an axis through which effluent flows in use. The coupling component may be angled with respect to the plane of the aperture when the coupling component is in the extended position.

In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough; a support membrane bonded to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the at least one foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the at least one foldable portion has a variable height when in the extended position, further wherein the aperture has a plane perpendicular to an axis through which effluent flows in use, and the coupling component is angled with respect to the plane of the aperture when the coupling component is in the extended position.

The support membrane and the at least one foldable portion may comprise a circumference.

The or each of the at least one foldable portion may comprise at least one tubular segment. The height of the at least one tubular segment may vary about its circumference.

The or each of the at least one foldable portion may comprise at least two tubular segment. The height of each of the at least two tubular segments may vary about its circumference.

In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough; a support membrane bonded to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the at least one foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the at least one foldable portion has a variable height when in the extended position, further wherein the at least one foldable portion comprises at least two tubular segments; and wherein the height of each tubular segment varies about its circumference.

The at least two tubular segments may overlap, or at least partially overlap, when in the retracted position. Advantageously, this means that, when in the retracted position, the overlapping tubular segments have a reduced height profile compared to that of an ostomy appliance in which any tubular segments of a foldable portion do not overlap when in the retracted position. This is favourable for the ostomate, not least because in the retracted position, the ostomy appliance maintains a discreet profile.

In embodiments comprising more than one tubular segment, adjacent tubular segments may be joined to one another at a fold line.

The foldable portion may comprise a first tubular segment and a second tubular segment. The first tubular segment may be arranged proximal to the aperture relative to the second segment. The first tubular segment may be bonded directly or indirectly to the baseplate. In particular, the first tubular segment may be bonded directly or indirectly to an inner surface of the baseplate. The inner surface of the baseplate may be angled with respect to a plane of the aperture. The first tubular segment may be bonded directly or indirectly to the angled inner surface of the baseplate. The second tubular segment may be bonded directly or indirectly to the coupling component.

The height of the at least one foldable portion is measured when the ostomy appliance is in the extended position. The height of the foldable portion at any point on its circumference, is the sum of the height of the, or each, tubular segment at that point.

The height of the at least one foldable portion may vary continuously around the circumference of the at least one foldable portion. The height of the at least one foldable portion may vary around at least about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or at least about 95%, of the circumference of the at least one foldable portion. The height of the at least one foldable portion may vary around about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 95%, of the circumference of the at least one foldable portion.

The height of the at least one foldable portion may vary step-wise around the aperture.

In the extended position, the at least one foldable portion may comprise a point of maximum height. The point of maximum height of the at least one foldable portion is the point on the circumference of the at least one foldable portion at which the height of the at least one foldable portion is at its greatest.

The point of maximum height may comprise a region of the at least one foldable portion which has the same height throughout.

The region of the at least one foldable portion which has the same height as the point of maximum height may be about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or about 95%, of the circumference of the support membrane at the foldable portion.

The region of the at least one foldable portion which has the same height as the point of maximum height may be at least about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or at least about 95%, of the circumference of the support membrane at the foldable portion.

The region of the at least one foldable portion which has the same height as the point of maximum height may be no more than about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or no more than about 95%, of the circumference of the support membrane at the foldable portion.

In the extended position, the at least one foldable portion may comprise a point of minimum height. The point of minimum height of the at least one foldable portion is the point on the circumference of the at least one foldable portion at which the height of the at least one foldable portion is at its smallest.

The point of minimum height may comprise a region of the at least one foldable portion which has the same height throughout. The region of the at least one foldable portion which has the same height as the point of minimum height may be about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or about 95%, of the circumference of the support membrane at the foldable portion.

The region of the at least one foldable portion which has the same height as the point of minimum height may be at least about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or at least about 95%, of the circumference of the support membrane at the foldable portion.

The region of the at least one foldable portion which has the same height as the point of minimum height may be no more than about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or no more than about 95%, of the circumference of the support membrane at the foldable portion.

The point of maximum height may be diametrically opposite, or at least substantially diametrically opposite, to the point of minimum height.

The height of the at least one foldable portion may increase continuously from the point of the minimum height to the point of maximum height.

In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough; a support membrane bonded to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the at least one foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the at least one foldable portion has a variable height when in the extended position, further wherein in the extended position, the foldable portion comprises a point of maximum height and a point of minimum height, and wherein the height of the foldable portion increases continuously from the point of minimum height to the point of maximum height.

The height of the at least one foldable portion may increase step- wise from the point of the minimum height to the point of maximum height.

The height of the at least one foldable portion at the point of maximum height may be about 8.0 mm, about 8.5 mm, about 9.0 mm, about 9.5 mm, about 10.0 mm, about 10.5 mm, about 11.0 mm, about 11.5 mm, about 12.0 mm, about 12.5 mm, about 13.0 mm, about 13.5 mm, about 14.0 mm, about 14.5 mm, about 15.0 mm, about 15.5 mm, or about 16.0 mm. The height of the at least one foldable portion at the point of maximum height may be at least about 8.0 mm, about 8.5 mm, about 9.0 mm, about 9.5 mm, about 10.0 mm, about 10.5 mm, about 11.0 mm, about 11.5 mm, about 12.0 mm, about 12.5 mm, about 13.0 mm, about 13.5 mm, about 14.0 mm, about 14.5 mm, about 15.0 mm, about 15.5 mm, or at least about 16.0 mm.

The height of the at least one foldable portion at the point of maximum height may be no more than about 8.0 mm, about 8.5 mm, about 9.0 mm, about 9.5 mm, about 10.0 mm, about 10.5 mm, about 11.0 mm, about 11.5 mm, about 12.0 mm, about 12.5 mm, about 13.0 mm, about 13.5 mm, about 14.0 mm, about 14.5 mm, about 15.0 mm, about 15.5 mm, or no more than about 16.0 mm.

The height of the at least one foldable portion at the point of maximum height may be from about 8.0 mm to about 16.0 mm, from about 8.0 mm to about 15.0 mm, from about 8.0 mm to about 14.0 mm, from about 8.0 mm to about 13.0 mm, from about 8.0 mm to about 12.0 mm, from about 8.0 mm to about 11.0 mm, from about 8.0 mm to about 10.0 mm, or from about 8.0 mm to about 9.0 mm.

The height of the at least one foldable portion at the point of maximum height may be from about 9.0 mm to about 16.0 mm, from about 9.0 mm to about 15.0 mm, from about 9.0 mm to about 14.0 mm, from about 9.0 mm to about 13.0 mm, from about 9.0 mm to about 12.0 mm, from about 9.0 mm to about 11.0 mm, or from about 9.0 mm to about 10.0 mm.

The height of the at least one foldable portion at the point of maximum height may be from about 10.0 mm to about 16.0 mm, from about 10.0 mm to about 15.0 mm, from about 10.0 mm to about 14.0 mm, from about 10.0 mm to about 13.0 mm, from about 10.0 mm to about 12.0 mm, or from about 10.0 mm to about 11.0 mm.

The height of the at least one foldable portion at the point of maximum height may be from about 11.0 mm to about 16.0 mm, from about 11.0 mm to about 15.0 mm, from about 11.0 mm to about 14.0 mm, from about 11.0 mm to about 13.0 mm, or from about 11.0 mm to about 12.0 mm. The height of the at least one foldable portion at the point of maximum height may be from about 12.0 mm to about 16.0 mm, from about 12.0 mm to about 15.0 mm, from about 12.0 mm to about 14.0 mm, or from about 12.0 mm to about 13.0 mm.

The height of the at least one foldable portion at the point of maximum height may be from about 13.0 mm to about 16.0 mm, from about 13.0 mm to about 15.0 mm, or from about 13.0 mm to about 14.0 mm.

The height of the at least one foldable portion at the point of maximum height may be from about 14.0 mm to about 16.0 mm, or from about 14.0 mm to about 15.0 mm.

The height of the at least one foldable portion at the point of maximum height may be from about 15.0 mm to about 16.0 mm.

The height of the at least one foldable portion at the point of maximum height may be about 1.1 times, about 1.2 times, about 1.3 times, about 1.4 times, about 1.5 times, about 1.6 times, about 1.7 times, about 1.8 times, about 1.9 times, about 2.0 times, about 2.1 times, about 2.2 times, about 2.3 times, about 2.4 times, about 2.5 times, about 2.6 times, about 2.7 times, about 2.8 times, about 2.9 times, about 3.0 times, about 3.1 times, about 3.2 times, about 3.3 times, about 3.4 times, about 3.5 times, about 3.6 times, about 3.7 times, about 3.8 times, about 3.9 times, about 4.0 times, about 4.1 times, about 4.2 times, about 4.3 times, about 4.4 times, about 4.5 times, about 4.6 times, about 4.7 times, about 4.8 times, about 4.9 times, or about 5.0 times, greater than the height of the at least one foldable portion at the point of minimum height.

The height of the at least one foldable portion at the point of maximum height may be at least about 1.1 times, about 1.2 times, about 1.3 times, about 1.4 times, about 1.5 times, about 1.6 times, about 1.7 times, about 1.8 times, about 1.9 times, about 2.0 times, about 2.1 times, about 2.2 times, about 2.3 times, about 2.4 times, about 2.5 times, about 2.6 times, about 2.7 times, about 2.8 times, about 2.9 times, about 3.0 times, about 3.1 times, about 3.2 times, about 3.3 times, about 3.4 times, about 3.5 times, about 3.6 times, about 3.7 times, about 3.8 times, about 3.9 times, about 4.0 times, about 4.1 times, about 4.2 times, about 4.3 times, about 4.4 times, about 4.5 times, about 4.6 times, about 4.7 times, about 4.8 times, about 4.9 times, or at least about 5.0 times, greater than the height of the at least one foldable portion at the point of minimum height.

The height of the at least one foldable portion at the point of maximum height may be no more than about 1.1 times, about 1.2 times, about 1.3 times, about 1.4 times, about 1.5 times, about 1.6 times, about 1.7 times, about 1.8 times, about 1.9 times, about

2.0 times, about 2.1 times, about 2.2 times, about 2.3 times, about 2.4 times, about 2.5 times, about 2.6 times, about 2.7 times, about 2.8 times, about 2.9 times, about 3.0 times, about 3.1 times, about 3.2 times, about 3.3 times, about 3.4 times, about 3.5 times, about 3.6 times, about 3.7 times, about 3.8 times, about 3.9 times, about 4.0 times, about 4.1 times, about 4.2 times, about 4.3 times, about 4.4 times, about 4.5 times, about 4.6 times, about 4.7 times, about 4.8 times, about 4.9 times, or no more than about 5.0 times, greater than the height of the at least one foldable portion at the point of minimum height.

The height of the at least one foldable portion at the point of maximum height may be from about 1.5 times to about 5.0 times, from about 1.5 times to about 4.5 times, from about 1.5 times to about 4.0 times, from about 1.5 times to about 3.5 times, from about 1.5 times to about 3.0 times, from about 1.5 times to about 2.5 times, or from about 1.5 times to about 2.0 times, greater than the height of the at least one foldable portion at the point of minimum height.

The height of the at least one foldable portion at the point of maximum height may be from about 2.0 times to about 5.0 times, from about 2.0 times to about 4.5 times, from about 2.0 times to about 4.0 times, from about 2.0 times to about 3.5 times, from about 2.0 times to about 3.0 times, or from about 2.0 times to about 2.5 times, greater than the height of the at least one foldable portion at the point of minimum height.

The height of the at least one foldable portion at the point of maximum height may be from about 2.5 times to about 5.0 times, from about 2.5 times to about 4.5 times, from about 2.5 times to about 4.0 times, from about 2.5 times to about 3.5 times, or from about 2.5 times to about 3.0 times, greater than the height of the at least one foldable portion at the point of minimum height. The height of the at least one foldable portion at the point of maximum height may be from about 3.0 times to about 5.0 times, from about 3.0 times to about 4.5 times, from about 3.0 times to about 4.0 times, or from about 3.0 times to about 3.5 times, greater than the height of the at least one foldable portion at the point of minimum height.

The height of the at least one foldable portion at the point of maximum height may be from about 3.5 times to about 5.0 times, from about 3.5 times to about 4.5 times, or from about 3.5 times to about 4.0 times, greater than the height of the at least one foldable portion at the point of minimum height.

The height of the at least one foldable portion at the point of maximum height may be from about 4.0 times to about 5.0 times, or from about 4.0 times to about 4.5 times, greater than the height of the at least one foldable portion at the point of minimum height.

The height of the at least one foldable portion at the point of maximum height may be from about 4.5 times to about 5.0 times greater than the height of the at least one foldable portion at the point of minimum height.

The height of the at least one foldable portion at the point of minimum height may be about 2.0 mm, about 2.5 mm, about 3.0 mm, about 3.5 mm, about 4.0 mm, about 4.5 mm, about 5.0 mm, about 5.5 mm, about 6.0 mm, about 6.5 mm, about 7.0 mm, about 7.5 mm, or about 8.0 mm.

The height of the at least one foldable portion at the point of minimum height may be at least about 2.0 mm, about 2.5 mm, about 3.0 mm, about 3.5 mm, about 4.0 mm, about 4.5 mm, about 5.0 mm, about 5.5 mm, about 6.0 mm, about 6.5 mm, about 7.0 mm, about 7.5 mm, or at least about 8.0 mm.

The height of the at least one foldable portion at the point of minimum height may be no more than about 2.0 mm, about 2.5 mm, about 3.0 mm, about 3.5 mm, about 4.0 mm, about 4.5 mm, about 5.0 mm, about 5.5 mm, about 6.0 mm, about 6.5 mm, about 7.0 mm, about 7.5 mm, or no more than about 8.0 mm.

The height of the at least one foldable portion at the point of minimum height may be from about 2.0 mm to about 8.0 mm, from about 2.0 mm to about 7.0 mm, from about 2.0 mm to about 6.0 mm, from about 2.0 mm to about 5.0 mm, from about 2.0 mm to about 4.0 mm, or from about 2.0 mm to about 3.0 mm.

The height of the at least one foldable portion at the point of minimum height may be from about 3.0 mm to about 8.0 mm, from about 3.0 mm to about 7.0 mm, from about 3.0 mm to about 6.0 mm, from about 3.0 mm to about 5.0 mm, or from about 3.0 mm to about 4.0 mm.

The height of the at least one foldable portion at the point of minimum height may be from about 4.0 mm to about 8.0 mm, from about 4.0 mm to about 7.0 mm, from about 4.0 mm to about 6.0 mm, or from about 4.0 mm to about 5.0 mm.

The height of the at least one foldable portion at the point of minimum height may be from about 5.0 mm to about 8.0 mm, from about 5.0 mm to about 7.0 mm, or from about 5.0 mm to about 6.0 mm.

The height of the at least one foldable portion at the point of minimum height may be from about 6.0 mm to about 8.0 mm, or from about 6.0 mm to about 7.0 mm.

The height of the at least one foldable portion at the point of minimum height may be from about 7.0 mm to about 8.0 mm.

In some embodiments, there may be provided an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough; a support membrane bonded to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the at least one foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the at least one foldable portion has a variable height when in the extended position, further wherein in the extended position, the foldable portion comprises a point of maximum height and a point of minimum height.

The support membrane may have two stable positions. As such, the support membrane may have bistable positions. The support membrane may have at least two stable positions. For example, the support membrane may have three, four, five, six, or more, stable positions. In embodiments comprising a support membrane having bistable positions, the bistable positions may be a retracted position and an extended position.

The support membrane may be configured to allow the coupling component to transition between the retracted position and the extended position. The support membrane may be configured to hold itself stably in each of the retracted position and the extended position. The support membrane may be configured to hold itself stably in each of the retracted position and the extended position by means of internal stress in the material of the support membrane.

In the retracted position, the support membrane may hold the coupling component to bear directly or indirectly against the baseplate. As such, in the retracted position, the coupling component may be held close to the baseplate which prevents, or at least resists, sagging of the support membrane and the pouch. Moreover, in the retracted position, the ostomy appliance, in particular the support membrane and coupling component, maintains a low profile height. This is favourable for the ostomate, not least because in the retracted position, the ostomy appliance maintains a discreet profile.

In the extended position, the coupling component may be displaced away from the baseplate. Advantageously, in the extended position, the support membrane can hold the coupling component spaced from the baseplate, without any pulling force required to be maintained upon the underlying skin that may be uncomfortable to the ostomate.

The variable height of the at least one foldable portion means that the extension of the support membrane is not equal at all points around the central axis which extends through the centre of the aperture when the coupling component is in an extended position. Thus, in use, when the support membrane is extended (i.e., into the extended position), the coupling component can be displaced away from the baseplate to various lengths depending on the height of the at least one foldable portion. For example, a part of the foldable portion having a relatively short height will allow for a smaller displacement, away from the baseplate, of the coupling component connected to that part of the support membrane. Moreover, a part of the foldable portion having a relatively tall height will allow for a larger displacement, away from the baseplate, of the coupling component connected to that part of the support membrane.

Moreover, in the extended position, a part of the coupling component associated with the point of minimum height of the foldable portion may be displaced away from the baseplate to a lesser extent than a part of the coupling component associated with the point of maximum height of the foldable portion.

The invention, therefore, provides for an ostomy appliance which can be arranged such that the coupling component may be displaced from the baseplate to a greater extent at one side of the ostomy appliance than another.

The ostomy appliance may comprise a top and a bottom of the baseplate (viewed when in use). In some embodiments, the ostomy appliance may be arranged such that the point of minimum height of the foldable portion is arranged at the top of the baseplate, and the point of maximum height is arranged at the bottom of the baseplate. Thus, the invention may be arranged such that a top side (viewed when in use) of the coupling component can be displaced from the baseplate to a lesser extent than a lower side of the coupling component. Advantageously, therefore, the invention prevents, or at least significantly reduces, sagging of the pouch which allows the ostomy appliance to be worn discreetly for longer periods of time, even when the pouch is occupied with a significant amount of effluent.

Further advantageously, as the invention provides for an ostomy appliance comprising a coupling component which can be displaced from the baseplate to a lesser extent at one side of the ostomy appliance compared to another, in the retraced position, the ostomy appliance may have an extremely low profile, such that the profile of the ostomy appliance may have a height which is not significantly greater than that of the baseplate.

The support membrane may be formed of a plastic film. The plastic film may be resiliently stretchable, or it may be substantially non- stretchable. Suitable plastic films include, for example, ethylene vinyl acetate copolymer (EVA), polyethylene (PE) or metalocene film. The plastic film may have a thickness of between 0.05 mm and 0.50 mm. The invention according to the second aspect may include any features, including optional features, of the invention according to any other aspect.

According to a third aspect of the invention, there is provided a method for manufacturing an ostomy appliance, the method comprising the steps: a. providing a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; b. providing a support membrane; c. providing a coupling component for attaching to a fluid collection pouch; d. bonding the support membrane to the coupling component and to the angled inner surface of the baseplate.

The angled inner surface of the baseplate may be flat, or at least substantially flat.

The method may comprise a step of bonding the support membrane to the angled inner surface of the baseplate by heat-welding, laser-bonding, ultrasonic welding or adhesive bonding.

The support membrane may comprise at least one foldable portion which extends around the aperture, the at least one foldable portion having a variable height.

The angled inner surface of the baseplate may comprise a flat, or at least substantially flat, portion and a curved portion which is concave relative to the plane of the aperture, and in which the support membrane is bonded to the flat, or at least substantially flat, portion and is not bonded to the curved portion. The ostomy appliance may be an ostomy appliance according to the first aspect.

The invention according to the third aspect may include any features, including optional features, of the invention according to any other aspect.

According to a fourth aspect of the invention, there is provided a method for manufacturing an ostomy appliance, the method comprising the steps: a. providing a baseplate having an aperture therein to permit the passage of effluent therethrough; b. bonding a support membrane to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the at least one foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the at least one foldable portion has a variable height when in the extended position.

The baseplate may comprise an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture. The baseplate may comprise an inner surface angled with respect to the plane of the aperture. The support membrane may be bonded to the angled inner surface of the baseplate.

The at least one foldable portion may comprise a point of maximum height and a point of minimum height.

The part of the at least one foldable portion comprising the point of maximum height may be diametrically opposite, or at least substantially diametrically opposite, to the part of the at least one foldable portion comprising the point of minimum height.

The ostomy appliance may be an ostomy appliance according to the second aspect. The invention according to the fourth aspect may include any features, including optional features, of the invention according to any other aspect.

According to a fifth aspect of the invention, there is provided a method of using an ostomy appliance, the method comprising the steps: a. providing an ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture and which comprises an adhesive layer, and an inner surface angled with respect to the plane of the aperture; a support membrane bonded to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane is bonded to the angled inner surface of the baseplate; b. adhering the ostomy appliance to a user’s skin surrounding a stoma; c. attaching a pouch for collecting effluent to the coupling component.

The support membrane may be configured to allow the coupling component to transition between the retracted position and the extended position.

The method may further comprise, after step (b) but before step (c), a step of transitioning the support membrane from the retracted position to the extended position. The support membrane may be transitioned from the retracted position to the extended position by pulling the coupling component away from the ostomate.

The method may further comprise, after step (c), a step of transitioning the support membrane from the extended position to the retracted position. The support membrane may be transitioned from the extended position to the retracted position by pushing the coupling component toward the ostomate.

The ostomy appliance may be an ostomy appliance according to the first aspect.

The invention according to the fifth aspect may include any features, including optional features, of the invention according to any other aspect.

According to a sixth aspect of the invention, there is provided a method of using an ostomy appliance, the method comprising the steps: a. providing an ostomy appliance comprising a baseplate having an aperture therein to permit the passage of effluent therethrough, the baseplate comprising an outer surface which faces an ostomate in use and which comprises an adhesive layer; a support membrane bonded to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the at least one foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the at least one foldable portion has a variable height when in the extended position; b. adhering the ostomy appliance to a user’ s skin surrounding a stoma; c. attaching a pouch for collecting effluent to the coupling component.

The ostomy appliance may be an ostomy appliance according to the second aspect.

The invention according to the sixth aspect may include any features, including optional features, of the invention according to any other aspect.

Detailed Description of the Invention

In order that the invention may be more clearly understood one or more embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:

Figure 1 is a partial front cross-section view of an ostomy appliance of the prior art in a retracted position;

Figure 2 is a front cross-section view of an embodiment of the invention in a retracted position;

Figure 3 is an expanded cross-section view of part of the embodiment of Fig. 2;

Figure 4 is an expanded cross-section view of a part of the embodiment of Fig. 2;

Figure 5 is a front cross-section view of the embodiment of Fig. 2, shown without a complimentary coupling part; and

Figure 6 is a front cross-section view of the embodiment of Fig. 2 in an extended position, shown without a complimentary coupling part.

Referring to Figure 1, there is shown an example of an ostomy appliance la of the prior art. The ostomy appliance la comprises a baseplate 2a, a support membrane 7a and a coupling component 8a. The baseplate 2a comprises a boundary 14a for an adhesive layer (not shown). The baseplate 2a comprises an aperture 3a which, in use, is arranged concentrically with a stomal orifice (not shown) of a user. The adhesive layer is arranged for attachment to an ostomate’s skin around the periphery of the stomal orifice.

The ostomy appliance la further comprises a coupling component 8a that is secured to the baseplate 2a around the aperture 3a by means of a support membrane 7a. The coupling component 8a is configured to releasably attachably engage to a complementary coupling part (not shown) secured to a fluid collection pouch (not shown) around an entrance aperture (not shown).

A central axis 4a extends through the centre of the aperture 3 a.

In the prior art and as shown in Figure 1, the coupling component 8 a and the complimentary coupling part form a mechanical engagement, typically by a releasable snap-fit coupling. The coupling component 8a comprises a flange 18a from which projects an upstanding rib 19a. The rib 19a comprises an undercut lug 23a for mechanical engagement with a complimentary receiver portion of the complimentary coupling part, and a resilient seal 20a. While not shown, the complementary coupling part typically comprises a channel for receiving the upstanding rib 19a. The channel has a complementary lug for interlocking with the undercut lug 23 a of the upstanding rib 19a when the rib 19a is received in the channel so as to provide the snap-fit coupling.

The support membrane 7a permits the coupling component 8a to move with respect to the baseplate 2a between a retracted position (Fig. 1) in which the coupling component 8a fits generally close to or against the baseplate 2a, and an extended position in which the coupling component 8a is spaced away from the baseplate 2a. Movement from the retracted position to the extended position is achieved typically by pulling the coupling component 8a away from the baseplate 2a. This unfolds a foldable portion 13a of the support membrane 7a, therefore, displacing the coupling component 8a away from the baseplate 2a.

The support membrane 7a comprises an outer periphery comprising a first interface region 10a attached to the coupling component 8a, and an inner periphery comprising a second interface region Ila bonded to the baseplate 2a. The second interface region Ila is bonded to an inner surface 6a of the baseplate 2a at a substantially flat surface which is in the plane of the aperture 3a of the baseplate 2a. In use, the aperture 3a is arranged in line with the ostomate’s stoma to allow the flow of effluent from the ostomate’s abdomen, through the stoma and into the fluid collection pouch. As such, in the prior art, the support membrane 7a is typically bonded to the inner surface 6a of the baseplate 2a on a substantially flat portion of the inner surface 6a which typically surrounds the aperture 3a, and is typically in the same plane as the aperture 3a. This arrangement of the prior art is disadvantageous, at least for the reasons described above herein. For example, the significant depth of the baseplate 2a as shown in Fig. 1, proximal to the aperture 3a and substantially above the second interface region Ila, means that the ostomy appliance la of the prior art provides a relatively large baseplate footprint and overall height profile, together with a considerably stiff baseplate 2a which, therefore, affords a disadvantageously inflexible ostomy appliance la. .

Moreover, bonding the second interface region 1 la to a flat inner surface 6a of the baseplate 2a around the aperture 3a means that when transitioning the support membrane 7a between the extended and retracted positions, in particular from the extended position to the retracted position, and when coupling and decoupling the fluid collection pouch to the coupling component 8a, the forces applied by the user are typically reacted directly back against the user’s abdomen in the region surrounding the stoma. This is particularly disadvantageous as many ostomates experience discomfort as a result of an attachment force applied through the ostomy appliance la to the skin, for example when two coupling parts are pressed together. The problem of discomfort is especially important during post-operative care, when the stoma surgery is recent and the abdominal skin is very tender.

Referring to Figures 2-6, an embodiment of an ostomy appliance 1 of the invention is shown.

The ostomy appliance 1 may comprise a baseplate 2, a support membrane 7 and a coupling component 8. The baseplate 2 may comprise a boundary 14 for an adhesive layer (not shown). The baseplate 2 comprises an aperture 3 which, in use, may be arranged concentrically with a stomal orifice (not shown) of an ostomate. The adhesive layer may be arranged for attachment to the ostomate’ s skin around the periphery of the stomal orifice. The adhesive layer may comprise any suitable skin-friendly ostomy adhesive, such as a hydrocolloid containing adhesive.

The ostomy appliance 1 may further comprise a coupling component 8 that is secured to the baseplate 2 around the aperture 3 by means of a support membrane 7. The coupling component 8 is configured to releasably attachably engage to a complementary coupling part 17 secured to a fluid collection pouch (not shown) around an entrance aperture (not shown).

A central axis 4 extends through the centre of the aperture 3.

In the described embodiment and as shown in Figure 4, the coupling parts 8, 17 may form a mechanical engagement (for example, a mechanical interlock or an interference fit). The coupling component 8 may comprise a flange 18 from which projects an upstanding rib 19. The rib 19 may comprise an undercut lug 23 and a resilient seal 20. The complementary coupling part 17 may comprise a channel 28 for receiving the upstanding rib 19. The channel 28 may have a complementary lug 24 for interlocking with the undercut lug 23 of the upstanding rib 19 when the rib 19 is received in the channel 28 so as to provide a snap-fit coupling. The two coupling parts 8, 17 may be made from moulded plastics that are stiffly flexible with a self-supporting shape.

The support membrane 7 comprises an outer periphery comprising a first interface region 10 attached to the coupling component 8, and an inner periphery comprising a second interface region 11 bonded to an angled inner surface 9 of the baseplate 2. The support membrane 7, in particular the second interface region 11, may be bonded to the angled inner surface 9 of the baseplate 2 by any suitable technique, such as heat-welding, laser-bonding or adhesive bonding. Alternatively, the support membrane 7 may be integrally formed (e.g., moulded) with another component of the ostomy appliance 1, such as the coupling component 8, and bonded to the angled inner surface 9 of the baseplate 2. In the described embodiment, the support membrane 7, in particular the second interface region 11 , is bonded to the angled inner surface 9 of the baseplate 2 by heat-welding. The angled inner surface 9 of the baseplate 2 is angled with respect to the plane of the aperture 3. The angled inner surface 9 may be flat, or at least substantially flat. The angled inner surface 9 of the baseplate 2 may be concave with respect to the plane of the aperture 3. The angled inner surface 9 of the baseplate 2 may be at an angle of from about 30° to about 60° with respect to the plane of the aperture 3 and, in the described embodiment, is angled at an angle of about 45° with respect to the plane of the aperture 3.

The support membrane 7 permits the coupling component 8 to move with respect to the baseplate 2 between a retracted position (Figs. 2 and 5) in which the coupling component 8 fits generally close to or against the baseplate 2, and an extended position (Fig. 6) in which the coupling component 8 is spaced away from the baseplate 2.

In this embodiment, the support membrane 7 is bistable. The support membrane 7 holds the coupling component 8 stably in the retracted position as a first stable position and in the extended position as a second stable position. The support membrane 7 may be regarded as giving the coupling component 8 a "floatable" characteristic in the sense that the coupling component 8 is displaceable away from the baseplate 2.

The support membrane 7 may be transitioned between the retracted and extended positions by manual finger pressure being applied, for example, by the ostomate.

In the extended position, the support membrane 7 may have a three-dimensional flared shape, which can be inherently self-supporting. The flared shape may, for example, be substantially conical (for example, substantially frusto-conical). The support membrane 7 may optionally be formed (e.g., thermoformed from sheet material, or moulded) in this shape as a natural shape, or the support membrane 7 may be formed in a different shape and hold itself stably in the flared shape by internal stress in the material of the support membrane 7. In the extended position, the first interface region 10 and the second interface region 11 of the support membrane 7 are substantially spaced from each other along the axis of a through passage through the support membrane 7. The support membrane 7 may comprise a foldable portion 25. The foldable portion 25 may comprise at least one tubular segment. In the described embodiment, and as shown in Fig. 3, the foldable portion 25 comprises two tubular segments, i.e., a first tubular segment 22 and a second tubular segment 21. The first tubular segment 22 may be joined to the second tubular segment 21 by a fold line 13. In the retracted position, as shown in Fig. 3, the foldable portion 25 is folded such that the first tubular segment 22 and the second tubular segment 21 substantially overlap with one another so that one segment may invert about the fold line 13 to nest against the other segment in the retracted condition.

In the retracted position, the support membrane 7 may adopt a folded tube configuration. In the described embodiment, the support membrane 7 comprises one foldable portion 25. The support membrane 7 may be formed (e.g., molded or thermoformed) in the retracted shape, or it may hold itself stably in this shape by internal stress in the material of the support membrane 7. In the retracted position, the first interface region 10 and the second interface region 11 of the support membrane 7 are relatively closer together, when viewed in an axial direction, compared to when in the extended position.

The foldable portion 25 may overcenter to accommodate the transition between the stable shapes. The height of the foldable portion 25 may be one of the geometric factors that determines the relative stability of the material in the two stable positions.

The support membrane 7 is generally tubular, forming an extended tube when in the extended position, and a folded tube when in the retracted position.

The first tubular segment 22 may be arranged proximal to the aperture 3 relative to the second tubular segment 21.

The height of the at least one foldable portion 25 is measured when the ostomy appliance 1 is in the extended position, as shown in Figure 6. The height of the foldable portion 25 is measured at any point on its circumference and is the sum of the height of each tubular segment 21, 22 at that point.

The foldable portion 25 may extend around the aperture 3. The foldable portion

25 may have a variable height. The foldable portion 25 may comprise a point of minimum height 15 and a point of maximum height 16. The point of maximum height 16 of the foldable portion 25 may be about 2.5 times greater than the point of minimum height 15 of the foldable portion 25. The height of the foldable portion 25 may increase continuously, around the aperture 3, from the point of minimum height 15 to the point of maximum height 16. The part of the foldable portion 25 comprising the point of maximum height 16 may be diametrically opposite, or at least substantially diametrically opposite, to the part of the foldable portion 25 comprising the point of minimum height 15. In the described embodiment, and as shown in Fig. 6, the height of the foldable portion 25 at its point of minimum height 15 may be measured as the sum of the height B3 of the first tubular segment 22 and the height B4 of the second tubular segment 21. Also as shown in Fig. 6, the height of the foldable portion 25 at its point of maximum height 16 may be measured as the sum of the height Bl of the first tubular segment 22 and the height B2 of the second tubular segment 21.

The flexibility of the material, and the foldable portion 25, may allow overcentering movement between the two stable positions. The support membrane 7 may be moulded in one condition (such as the retracted condition), and be stable in the other condition by virtue of internal stresses in the material.

While each user may have a preferred method of coupling and decoupling the fluid collection pouch to the baseplate 2, one such method is such that in use, when the ostomy appliance 1 is worn on the body, and the ostomate desires to attach a fluid collection pouch, the ostomate first pulls the coupling component 8 away from the body. The support membrane 7 transitions from its retracted position to its extended position, by the unfolding of the foldable portion 25, and provides an annular space 12 between the coupling component 8 and the baseplate 2 for the user to insert one or more fingers (not shown) of one or both hands. Advantageously, although the user does have to apply some force for a very short period of time to displace the coupling component 8, once in the extended configuration the user does not have to maintain any pulling force on the coupling component 8, and so the underlying skin is relieved of such uncomfortable force while the coupling component 8 remains in its displaced, extended position. The user may be inclined to begin coupling the fluid collection pouch to the baseplate at the point of maximum height 16, or in the region of the point of maximum height 16, and work their way around the circumference of the support membrane 7 to the point of minimum height 15, or in the region of the point of minimum height 15.

To fit the fluid collection pouch, the user then presses the complementary coupling part 17 into snap-fit engagement with the coupling component 8, as described above, while at the same time using their fingers to brace the coupling component 8, in order to relieve the attachment force from being transmitted through the baseplate 2 to the ostomate's underlying skin.

Once the fluid collection pouch has been fitted, the user removes their fingers from the annular space 12, and then gently pushes the coupling component 8 towards the baseplate 2. This pushing action transitions the support membrane 7 from its extended position to its retracted position, and such that the foldable portion 25 is folded, and the coupling component 8 is moved into a close fit against the baseplate 2.

The stable shape of the support membrane 7 in its retracted position resists sagging of the ostomy appliance 12, in particular of the fluid collection pouch, away from the ostomate’s body. The ostomy appliance 1 may, therefore, be conveniently used for post-operative care and for everyday use. In the extended position, the variable height of the support membrane 7 means that the ostomy appliance 1 resists sagging, therefore, aiding the discretion of wearing an ostomy appliance afforded to ostomates.

The support membrane 7 is made of any suitable material that can provide the desired stable shapes, with the desired stability of each shape. For example, the support membrane 7 may be made of plastic film. The plastic film may be resiliently stretchable, or it may be substantially non-stretchable. Suitable films include, for example, ethylene vinyl acetate copolymer (EVA), polyethylene (PE) or metalocene film, with a thickness of between 0.050 mm and 0.50 mm.

In the described embodiments, because the support membrane 7 is bonded to the angled inner surface 9 of the baseplate, the diameter of the aperture 3 may be larger than the diameter of corresponding apertures in ostomy appliances of the prior art which comprise a support membrane bonded to an inner surface of a baseplate which is in the plane of the aperture and which is directly adjacent to the aperture. Thus, the ostomy appliance of the described embodiments may be manufactured comprising an aperture 3 of various diameters to suit the accommodate specific customer preferences for postoperative care, and also different customer preferences for everyday use. The ostomy appliances of the described embodiments, therefore, find applicability with various sizes of stomas meaning that the ostomy appliance of the invention can be used with a greater number of ostomates compared to many ostomy appliances of the prior art.

Further advantages of the ostomy appliance of the described embodiments are described above herein.

The one or more embodiments are described above by way of example only. Many variations are possible without departing from the scope of protection afforded by the appended claims.

Claims

1. An ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; a support membrane bonded to the baseplate and to a coupling component for attaching to a fluid collection pouch; wherein the support membrane is bonded to the angled inner surface of the baseplate.

2. An ostomy appliance according to claim 1, wherein the angled inner surface of the baseplate is flat, or at least substantially flat.

3. An ostomy appliance according to claim 1, wherein the angled inner surface of the baseplate is concave with respect to the plane of the aperture.

4. An ostomy appliance according to any preceding claim, wherein the angled inner surface of the baseplate is at an angle of from about 10° to about 60° with respect to the plane of the aperture.

5. An ostomy appliance according to any preceding claim, wherein the support membrane is bonded to the angled inner surface of the baseplate by heatwelding, laser-bonding, ultrasonic welding or adhesive bonding.

6. An ostomy appliance according to any preceding claim, wherein the outer surface of the baseplate comprises an adhesive layer.

7. An ostomy appliance according to claim 6, wherein the adhesive layer comprises a hydrocolloid.

8. An ostomy appliance according to any preceding claim, wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the foldable portion has a variable height when in the extended position.

9. An ostomy appliance according to any preceding claim, wherein the support membrane is bonded directly to the angled inner surface of the baseplate.

10. An ostomy appliance comprising: a baseplate having an aperture therein to permit the passage of effluent therethrough; a support membrane bonded to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the at least one foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the at least one foldable portion has a variable height when in the extended position.

11. An ostomy appliance according to claim 10, wherein the aperture has a plane perpendicular to an axis through which effluent flows in use, and the coupling component is angled with respect to the plane of the aperture when the coupling component is in the extended position.

12. An ostomy appliance according to claim 10 or 11, wherein the at least one foldable portion comprises at least two tubular segments; and wherein the height of each tubular segment varies about its circumference.

13. An ostomy appliance according to claim 12, wherein the at least two tubular segments overlap, or at least partially overlap, when in the retracted position.

14. An ostomy appliance according to claim 12 or 13, wherein adjacent tubular segments are joined at a fold line.

15. An ostomy appliance according to claim 14, wherein a first tubular segment is bonded directly or indirectly to the baseplate, in particular to an inner surface of the baseplate.

16. An ostomy appliance according to claim 14 or 15, wherein a second tubular segment is bonded directly or indirectly to the coupling component.

17. An ostomy appliance according to any of claims 10 to 16, wherein in the extended position, the foldable portion comprises a point of maximum height and a point of minimum height.

18. An ostomy appliance according to claim 17, wherein point of maximum height is diametrically opposite, or at least substantially diametrically opposite, to the point of minimum height.

19. An ostomy appliance according to claim 17 or 18, wherein the height of the foldable portion increases continuously from the point of minimum height to the point of maximum height.

20. An ostomy appliance according to any of claims 17 to 19, wherein the height at the point of maximum height of the foldable portion is from about 1.5 times to about 5.0 times greater than the height at the point of minimum height of the foldable portion.

21. An ostomy appliance according to claim 20, wherein the height at the point of maximum height of the foldable portion is about 2.5 times greater than the height at the point of minimum height of the foldable portion.

22. An ostomy appliance according to any of claims 17 to 21, wherein the height at the point of maximum height of the foldable portion is from about 8.0mm to about 16.0mm, and/or wherein the height at the point of minimum height of the foldable portion is from about 2.0 mm to about 6.0 mm.

23. An ostomy appliance according to any of claims 17 to 22, wherein in the extended position, a part of the coupling component associated with the point of minimum height is displaced away from the baseplate to a lesser extent than a part of the coupling component associated with the point of maximum height.

24. An ostomy appliance according to any preceding claim, wherein the support membrane is formed of a plastics film.

25. An ostomy appliance according to any preceding claim, wherein the support membrane comprises a through passage.

26. An ostomy appliance according to any preceding claim, wherein the support membrane comprises a first interface region connected to the coupling component.

27. An ostomy appliance according to any preceding claim, wherein the support membrane comprises a second interface region bonded to the angled inner surface of the baseplate.

28. An ostomy appliance according to any preceding claim, wherein the support membrane has bistable positions.

29. An ostomy appliance according to claim 28, wherein the bistable positions are a retracted position and an extended position.

30. An ostomy appliance according to claim 29, wherein in the extended position, the coupling component is displaced away from the baseplate.

31. An ostomy appliance according to claim 29 or 30, when dependent upon claims 26 and 27, wherein in the extended position, the first and second interface regions are substantially spaced apart in an axial direction of the through passage.

32. An ostomy appliance according to claim 29 or 30, when dependent upon claims 26 and 27, wherein in the retracted position, the first and second interface regions bear directly or indirectly against one another.

33. An ostomy appliance according to any of claims 29 to 32, wherein in the extended position, the ostomy appliance comprises an annular space between the coupling component and the baseplate.

34. An ostomy appliance according to claim 33, wherein the annular space is configured to allow an ostomate to manually brace the coupling component when fitting the pouch.

35. An ostomy appliance according to any of claims 29 to 34, wherein the support membrane has a configuration selected as one or more of: (i) an extended tube when in the extended position, (ii) a folded tube when in the retracted position.

36. An ostomy appliance according to any of claims 29 to 35, wherein the support membrane is configured to allow the coupling component to transition between the retracted position and the extended position.

37. An ostomy appliance according to any of claims 29 to 36, wherein the support membrane is configured to hold itself stably in each of the retracted position and the extended position.

38. An ostomy appliance according to claim 37, wherein the support membrane holds itself stably in each of the retracted position and the extended position by means of internal stress in the material of the support membrane.

39. An ostomy appliance according to any of claims 29 to 38, wherein the support membrane is configured to transition between the retracted position and the extended position when a predetermined force is applied.

40. An ostomy appliance according to any of claims 29 to 39, wherein in the retracted position, the support membrane holds the coupling component to bear directly or indirectly against the baseplate.

41. An ostomy appliance according to any of claims 29 to 40, wherein the support membrane is pleated when in the retracted position.

42. An ostomy appliance according to claim 41, wherein the pleated support membrane comprises at least one foldable portion.

43. An ostomy appliance according to claim 42, wherein the pleated support membrane comprises two, three, four, five, or more than five, folds.

44. A method of manufacturing an ostomy appliance, the method comprising the steps: a. providing a baseplate having an aperture therein to permit the passage of effluent therethrough, the aperture having a plane perpendicular to the axis through which effluent flows in use; the baseplate comprising an outer surface which faces an ostomate in use and is angled with respect to the plane of the aperture, and an inner surface angled with respect to the plane of the aperture; b. providing a support membrane; c. providing a coupling component for attaching to a fluid collection pouch; d. bonding the support membrane to the coupling component and to the angled inner surface of the baseplate.

45. A method of manufacturing an ostomy appliance according to claim 44, wherein the ostomy appliance is an ostomy appliance according to any preceding claim.

46. A method of manufacturing an ostomy appliance, the method comprising the steps: a. providing a baseplate having an aperture therein to permit the passage of effluent therethrough; b. bonding a support membrane to the baseplate and to a coupling component for attaching to a pouch; wherein the support membrane comprises at least one foldable portion which extends circumferentially around the aperture, wherein the at least one foldable portion is configured to allow the coupling component to transition between a retracted position and an extended position, further wherein the at least one foldable portion has a variable height when in the extended position.

47. A method of manufacturing an ostomy appliance according to claim 46, wherein the ostomy appliance is an ostomy appliance according to any of claims 1 to 43.