Convex shell for use in a base plate of an ostomy appliance

Abstract

A convex shell for use in a base plate of an ostomy appliance includes an annular ring with a through-going hole and a plurality of grooves extending transversely across the annular ring. The grooves alter the flexibility of the annular ring as a first portion of the annular ring is folded around a folding axis toward a second portion of the annular ring.

Claims

1. A convex shell for use in a base plate of an ostomy appliance, the convex shell comprising: an annular ring defined by an outer edge in a first plane and an inner edge in a second plane, the inner edge defining a through-going hole having a center axis, the first plane axially offset along the center axis from the second plane, the annular ring including: an outer planer surface extending radially inward from the outer edge in the first plane; an inner planer surface extending radially outward from the inner edge in the second plane; an intermediate surface extending radially inward from the outer planer surface to the inner planer surface; and a plurality of grooves, with each groove extending radially on a line aligned with a center of the through-going hole and formed in the outer planer surface and the inner planer surface and the intermediate surface, the plurality of grooves alters the flexibility of the annular ring as a first portion of the annular ring is folded around a folding axis toward a second portion of the annular ring.

2. The convex shell according to claim 1, wherein the plurality of grooves includes six grooves, wherein each of the six grooves includes a first groove wall and a second groove wall defining a folding angle α.

3. The convex shell according to claim 2, wherein the first groove wall and the second groove wall are made from different materials having different compression characteristics.

4. The convex shell according to claim 2, wherein not all of the six grooves define the same folding angle α so that the convex shell can provide flexibility in further intervals.

5. The convex shell according to claim 1, wherein the plurality of grooves is placed on a first side facing the user, when the product is in use.

6. The convex shell according to claim 1, wherein the plurality of grooves is placed on a second side facing away from the user, when the product is in use.

7. A convex shell for use in a base plate of an ostomy appliance, the convex shell comprising: an annular ring defined by an outer edge in a first plane and an inner edge in a second plane, the inner edge defining a through-going hole having a center axis, the first plane being axially offset along the center axis from the second plane, the annular ring including at least one groove extending radially on a line aligned with a center of the through-going hole and formed in the first plane and the second plane, the at least one groove adapted to alter the flexibility of the annular ring when the annular ring is folded around a folding axis.

8. The convex shell according to claim 7, wherein the at least one groove extends along the folding axis.

9. The convex shell according to claim 7, wherein a first resulting reactive force of the convex shell when an angle around the folding axis between a first portion of the annular ring and a second portion of the annular ring is between 180 and 90 degrees and is less than a second resulting reactive force of the convex shell when the angle around the folding axis between the first portion of the annular ring and the second portion of the annular ring is between 90 and 20 degrees.

10. The convex shell according to claim 7, wherein the at least one groove includes two opposite contact surfaces which move toward each other as a first portion of the annular ring is folded around the folding axis toward a second portion of the annular ring.

11. The convex shell according to claim 10, wherein a first force required to fold the first portion of the annular ring toward the second portion of the annular ring when the two opposite contact surfaces are not in contact with each other is less than a second force required to further fold the first portion of the annular ring toward the second portion of the annular ring when the two opposite contact surfaces are in contact with each other.

12. The convex shell according to claim 7, wherein the at least one groove is placed on a first side facing the user, when the product is in use.

13. The convex shell according to claim 7, wherein the at least one groove is placed on a second side facing away from the user, when the product is in use.

14. The convex shell according to claim 7, wherein the at least one groove includes a plurality of grooves formed across the annular ring.

15. The convex shell according to claim 14, wherein the plurality of grooves is placed on a first side facing the user and on the second side facing away from the user, when the product is in use.

16. The convex shell according to claim 14, wherein each groove of the plurality of grooves includes two opposite contact surfaces which move toward each other as the first portion of the annular ring is folded around the folding axis toward the second portion of the annular ring, the two opposite contact surfaces for each groove of the plurality of grooves contacting each other when the convex shell is folded to a predetermined angle around the folding axis.

17. The convex shell according to claim 16, wherein the predetermined angle is not the same for each groove of the plurality of grooves.

18. The convex shell according to claim 16, wherein each groove of the plurality of grooves extends in a radial direction.

19. The convex shell according to claim 16, wherein the plurality of grooves includes a plurality of first grooves and a plurality of second grooves, the plurality of first grooves extending in a first direction across the annular ring, and the plurality of second grooves extending in a second direction across the annular ring, the first direction transverse to the second direction.

20. The convex shell according to claim 16, wherein at least some of the plurality of grooves extend to the inner edge of the annular ring, at least some of the plurality of grooves extend to the outer edge of the annular ring.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The invention will now be described in detail with reference to the figures in which

(2) FIG. 1 discloses a cross-sectional view of the base plate according to the present invention,

(3) FIGS. 2 and 3 disclose cross-sectional view of the base plate when attached to the skin of a user,

(4) FIG. 4 discloses a testing device for determining the axial compression resistance of a base plate,

(5) FIG. 5 discloses bending of a base plate,

(6) FIGS. 6 and 7 disclose provision of a base plate in a bending resistance testing device, and

(7) FIG. 8 discloses a graph illustrating the combination of bending resistance and axial compression resistance of various embodiments of the invention.

(8) FIG. 9 shows, in perspective, a supporting device according to example 1,

(9) FIG. 10 shows, in section, the supporting device of FIG. 9 applied around a stoma,

(10) FIG. 11 shows the supporting device according to FIGS. 9 and 10 when the peristomal skin area around the stoma is moved.

(11) FIG. 12 shows, in perspective, a sub-example according to example 1,

(12) FIG. 13 shows a top view of the supporting device of FIG. 12 embedded in the adhesive of an adhesive wafer,

(13) FIG. 14 shows a sectional view of the supporting device of FIG. 13,

(14) FIG. 15 shows a supporting member according to example 2,

(15) FIG. 16 shows the supporting member of example 2 in section along lines II-II in FIG. 15,

(16) FIG. 17 shows the supporting member of example 2 in section along lines III-III in FIG. 15,

(17) FIG. 18 is a perspective view of a detail of a supporting member,

(18) FIG. 19 shows a supporting element of example 3,

(19) FIG. 20 shows a base plate having the supporting element of FIG. 19,

(20) FIG. 21 shows the base plate with the supporting element of FIG. 19 in section along line III-III in FIG. 20,

(21) FIG. 22 shows a convex shell having folding restriction means according to example 4,

(22) FIG. 23 shows the convex shell of FIG. 22 in section along line II-II in FIG. 22,

(23) FIG. 24 shows another version of a convex shell as described in example 4,

(24) FIG. 25 shows a convex shell according to example 5,

(25) FIG. 26 shows a sectional view of the convex shell of FIG. 25 along line A-A of FIG. 25,

(26) FIG. 27 is a graphic illustration plotting the measured bendability resistance and axial compression resistance of prior art devices and devices according to the invention.

DETAILED DESCRIPTION OF THE DRAWING

(27) FIG. 1 discloses a cross-sectional view of a base plate 100 comprising an adhesive wafer 102 and a convex supporting device 104. The convex supporting device 104 is secured to the adhesive wafer 102 in a first attachment zone 108 and in a second attachment zone 106. In the figures, the convex supporting device 104 and the adhesive wafer 102 are not secured to each other in the area between the first attachment zone 108 and the second attachment zone 106. This may especially be seen in FIG. 3.

(28) In FIGS. 2 and 3 the base plate 100 is secured to the skin 110 of a user by means of a skin friendly adhesive which is provided on a proximal side 112 of the adhesive wafer 102. Due to the convex shape of the convex supporting device 104, the base plate 100 is forced into contact with the skin 110 of the user substantially over its entire surface in cases where the stoma is provided in a concave cavity of the skin of the user.

(29) FIG. 4 discloses a testing device 114 for testing the axial compression resistance of the base plate 100. The testing device 114 comprises an upper axial testing part 116 and a lower axial testing part 118. During use, the base plate 100 is placed on the lower axial testing part 118 and the upper axial testing part 116 is moved towards the lower axial testing part 118 so as to incur a compression force on the base plate 100. In one embodiment, the base plate 100 is not retained in a transverse direction 120 during the test, whereby the compression force applied by the upper axial testing part 116 may cause a part of the base plate 100 to move in the transverse direction 120. In another embodiment, the base plate 100 is retained in the transverse direction 120, e.g. by adhering the base plate to the lower axial testing part 118 by means of the adhesive of the adhesive wafer 102.

(30) During the test, the maximum or peak axial compression resistance is determined by determining the maximum reaction force the base plate 100 exerts on upper axial testing part 116 and/or the lower axial testing part 118 during testing.

(31) FIG. 5 discloses the base plate 100 in an unbent state 122 and in a bent state 124. The bending resistance may be determined by using the method described in relation to FIGS. 6 and 7.

(32) Initially, a bending resistance testing device 126 is provided which comprises an upper bending testing part 128 and an lower bending testing part 130.

(33) Next, the base plate 100 is provided and inserted into the bending resistance testing device 126. The base plate 100 is inserted into the bending resistance testing device 126 by folding a most radial part 132 of the base plate 100 such that the width of the base plate substantially corresponds to the width of the convex supporting device 104. The base plate 100 is inserted into the bending resistance testing device 126 such that it is retained between the upper bending testing part 128 and the lower bending testing part 130 without any further holding or securing means.

(34) Subsequently, the upper bending testing part 128 and the lower bending testing part 130 are forced towards each other as is indicated by arrows 134. This causes the base plate 100 to be moved from the unbent state 122 which may be seen in FIG. 6, to the bent state 124 which may be seen in FIG. 7.

(35) During the bending action, the reaction force exerted by the base plate on the upper bending testing part 128 and the lower bending testing part 130 is determined and the maximum value is determined. This value is used as a measure for the bending resistance. Alternatively, the force exerted on the upper bending testing part 128 and the lower bending testing part 130, once the two parts 128,130 have been moved a predetermined distance, may be used as a measure for the bending resistance.

(36) FIG. 8 basically schematically shows a relationship between the bendability resistance, shown in the vertical second (y)-axis, and the axial compression resistance, shown in the horizontal first (x)-axis scaled to illustrate the boundaries of the invention. In embodiments, any base plate according to the invention is located in the indicated “new technology” area.

EXAMPLES

(37) In the following, a number of examples of convex supporting devices capable of achieving and controlling the axial compression resistance and/or bending resistance of the base plate of the invention are presented. The convex supporting device may also be referred to as a convex supporting element or a convex supporting member.

Example 1

(38) Example 1 relates to a supporting device for stabilizing a skin area comprising a proximal annular element for placing around the skin area to be stabilized and a distal annular element axially offset from the proximal annular element, the proximal annular element and the distal annular element being interconnected by at least one resilient element.

(39) The at least one resilient element allows for the annular elements to be axially displaced relative to each other, while still being biased towards a common neutral configuration. As understood in this example, the term resilient refers to a material or structure which is stretchable and compressible under application of a force, but which will return to its original shape when no force is applied.

(40) This provides a device where a skin area may be stabilized and supported in order to, for example, provide rest or easy access, while still allowing the wearer to move around and perform everyday activities. Moreover, the flexibility of the supporting device reduces the risk of for example pressure wounds and generally increases the comfort for the wearer.

(41) In the following, and in the application as a whole, it should be understood that the terms ‘proximal’ and ‘distal’ are used to describe relative orientation of objects and elements with reference to the surface of the skin. Thus, for example, the proximal annular element is closer to the skin than the distal annular element, and the proximal surface of the proximal annular element is the surface which faces the skin when the supporting device is worn, whereas the distal surface of the proximal annular element is the surface which faces away from the skin.

(42) The at least one resilient element may be a spring element. This provides a simple way of providing flexibility and movement between the distal and proximal annular ring.

(43) Alternatively or additionally, the at least one resilient element can be formed of a compressible material.

(44) The supporting device can be applied to the distal side of the adhesive wafer, i.e. to the non-adhesive side.

(45) The supporting device may have a convex shape thereby in itself forming a convex supporting device or it may be an integrated part of a convex device, e.g. a convex shell, in both instances forming a convex supporting device in a base plate of an ostomy appliance.

(46) An embodiment of the example concerns a supporting device for stabilizing a skin area comprising a proximal annular element for placing around the skin area to be stabilized and a distal annular element axially offset from the proximal annular element, the proximal annular element and the distal annular element being interconnected by at least one resilient element.

(47) Another embodiment of the example concerns a supporting device, wherein the at least one resilient element is a spring element.

(48) Another embodiment of the example concerns a supporting device, wherein the at least one resilient element is formed of a compressible material.

(49) Another embodiment of the example concerns a base plate for an ostomy appliance comprising an adhesive wafer for adhering to the skin surrounding a stoma and comprising a through-going hole in the adhesive wafer for receiving said stoma, wherein the base plate further comprises a supporting device of the example's other embodiments.

(50) Another embodiment of the example concerns a base plate, wherein the supporting device is integrated in a convex shell.

(51) Another embodiment of the example concerns a base plate, wherein the supporting device is at least partly embedded in the adhesive wafer.

(52) Another embodiment of the example concerns a base plate, wherein the supporting device is applied to the distal side of the adhesive wafer.

(53) Details of Example 1

(54) A supporting device 200 for supporting a skin area is shown in FIG. 9. The supporting device has a proximal annular ring 202. The proximal annular ring 202 is connected to a distal annular ring 203 via spring element 204′ and 204″.

(55) The proximal annular ring is formed as a circular ring and has a proximal through-going hole 205 which has a size suitable for enclosing a desired skin area, for example a stoma or a wound site.

(56) The distal annular ring is also formed as a circular ring and has a distal through-going hole 206. The distal annular ring has a larger circumference than the proximal annular ring. This allows for easy access to the proximal through-going hole 205 through the distal through-going hole 206.

(57) The proximal annular ring 202 and the distal annular ring 203 are displaced along the longitudinal axis A-A which extends through the centres of both the annular rings.

(58) The proximal annular ring 202 and the distal annular ring 203 are connected via the spring elements 204′ and 204″. The spring elements extend from the proximal surface 203″ of the distal annular ring and connects to the proximal annular ring 202 on its distal surface 202′.

(59) The spring elements 204′ and 204″ are resilient in at least the longitudinal direction along the longitudinal axis A-A. Thus, the proximal annular ring 202 and the distal annular ring 203 may be pressed towards each other or pulled away from each other in an axial direction along the axis A-A. However, the spring elements force them back into alignment and position when no force is applied to the supporting device. Accordingly, when applied the supporting device will be biased to a neutral position wherein the annular rings are in desired position relative to each other.

(60) FIGS. 10 and 11 illustrate, in section, the supporting device 200 attached to the skin 210 of a human being in order to support and stabilize the area around a stoma 211.

(61) In FIGS. 10 and 11, the supporting device 200 is applied so that the proximal annular ring 202 presses against the peristomal skin area 212, i.e. the skin surrounding the stoma. The distal annular ring 203 is held against the skin 202 by an adhesive wafer 207. Alternatively or additionally, a belt (not shown) may be used in order to keep the supporting device pressed against the skin. By pressing the distal annular ring 203 against the skin, force is applied to the proximal annular ring 202 via the spring elements 204′ and 204″.

(62) By dimensioning the spring elements 204′ and 204″, it is possible to obtain a necessary pressure on the peristomal skin area. Different pressure forces may be necessary in order to adapt the specific supporting device to a specific user. The specific user may need customized supporting devices in order to take into account the different conditions of the skin, such as the topography, for example scars and wounds. Thus, some users only require a low force, while others may require much higher pressure. A number of parameters may be altered in order to change the pressure force, for example the material of the spring elements can be changed or the thickness or other dimensions can be altered.

(63) When the proximal annular ring 202 presses against the peristomal skin area, the pressure causes a slight lifting of the stoma, or put differently, the protuberance of the stoma in relation to the peristomal skin is increased. This facilitates access to the stoma and the skin within the proximal through-going hole when, for example, cleaning or inspecting the stoma as well as during the use. The increased protruding of the stoma ensures that stomal output coming out of the stomal opening is directed more securely to the inside of for example a collecting bag (not shown) which can be attached to the supporting device or to a base plate comprising the supporting device.

(64) Moreover, this construction of the supporting device and application also keeps the stoma protected as the proximal annular ring provides increased stiffness thereby reducing the risk of strangulation or collapsing of the stoma or the immediate surrounding skin area. This kind of problem is often, but not exclusively, seen in relation to obese users where skin folds tend to close off the stoma or peristomal area. The stiffness of the proximal and distal annular rings may be modified in order to provide an appropriate balance between stiffness and flexibility in order to accommodate the needs of respective users. Consequently, the ability of the supporting device to resist bending and/or axial compression can be differentiated according to user needs.

(65) This is, for example, an advantage when the users move around, thereby folding and stretching the skin as shown in FIG. 11, where the supporting device 200 is shown when the user for example bends. Such a bend creates a fold in one side 213 and a stretch in the other side 214. The spring elements 204′ and 204″ absorb both the flexing and the folding. The proximal annular ring prevents the skin fold in and over the stoma.

(66) An additional sub-example of a spring element based supporting device 220 is shown in FIG. 12. Similar to the example of FIGS. 9-11, the supporting device is formed of a proximal annular ring 222 and a distal annular ring 223. The proximal and distal annular rings are interconnected by eight spring members 224. This provides improved stability.

(67) FIGS. 13 and 14 show how the supporting device 220 of FIG. 12 may alternatively be embedded into the adhesive 225 of an adhesive wafer 227 or base plate of an ostomy appliance with their through-going holes 226 and 228 aligned.

Example 2

(68) Example 2 relates to a supporting member connected to a base plate of an ostomy device. The supporting member comprises an annular ring defined by an outer edge and an inner edge defining a through-going hole having a central axis C-C, said ring comprising at least one stiffening element extending radially from the through-going hole towards the outer edge of the annular ring.

(69) This provides stiffening of the base plate in selected areas, which is advantageous in order to prevent collapsing around the stoma when the wearer moves in specific positions where the risk of collapse is high. However, at the same time, flexibility and thereby high comfort may still be maintained.

(70) The supporting member can advantageously be a convex shell wherein the outer edge and the inner edge are placed in separate planes offset in respect to each other along a central axis.

(71) The stiffening element can be provided by forming the at least one stiffening element in the form of a groove formed in the annular ring. The groove can, for example, have a U-shape when seen in cross-section. The groove can be formed when the supporting member is formed, for example by injection moulding or it can be provided afterwards for example by pressure forming the grooves into the annular ring.

(72) An inner circumference of the supporting member defined by its inner edge can be eccentrically arranged with respect to an outer circumference defined by its outer edge. This results in the distance between the outer and inner edge differing around the circumferential extent of the annular ring. This provides differentiated flexibility around the annular ring as larger areas, i.e. where the distance between the outer and inner edge is greater, will be stiffer and thus have a higher resistance against collapsing. Consequently, the ability of the supporting element to resist bending and/or axial compression can be differentiated according to user needs.

(73) An embodiment of the example concerns a supporting member for use in a base plate of an ostomy device, the supporting member comprising an annular ring defined by an outer edge and an inner edge defining a through-going hole having a central axis C-C, said ring comprising at least one stiffening element extending radially from the through-going hole towards the outer edge of the annular ring.

(74) Another embodiment of the example concerns a supporting member, wherein the supporting member is a convex shell in which the outer edge and the inner edge are placed in separate planes offset in respect to each other along the central axis C-C.

(75) Another embodiment of the example concerns a supporting member, wherein the at least one stiffening element is in the form of a groove formed in the annular ring.

(76) Another embodiment of the example concerns a supporting member, wherein the groove is U-shaped in cross-section.

(77) Another embodiment of the example concerns a supporting member, wherein an inner circumference defined by the inner edge is eccentrically arranged with respect to an outer circumference defined by the outer edge.

(78) Details of Example 2

(79) FIGS. 15-18 show a supporting member 300 having the advantages as described herein.

(80) The supporting member 300 is in the form of an annular ring which is defined by an outer edge 303 and an inner edge 304. The inner edge 304 also defines a through-going hole 305 through which a stoma can be received when the supporting member is incorporated into a base plate for use in an ostomy appliance.

(81) The through-going hole defines an axis C-C, corresponding to the central axis of the inner edge. The inner edge 304 is eccentrically placed in respect to the outer edge 303, thereby dividing the supporting member 300 into two areas, i.e. a first area 306 where the radial distance from the inner edge to the outer edge is larger than in a second area 307.

(82) Three stiffening elements 308, 309, 310 extend radially from the inner edge 304 towards the outer edge 303 in the first area 306. The stiffening elements are formed as grooves in the supporting member 300 having a U-shape when seen in cross-section, as can be seen in FIG. 17. This increases the stiffness of the first area 306, thereby reducing the risk that the first area 306 of the supporting member 300 collapses onto a stoma protruding through the through-going hole 305.

(83) The stiffening elements may also be solid so as not to form grooves as seen in the sub-example of FIG. 18. The stiffening elements 312 may project or extend axially from the proximal surface 311 of the convex supporting device, as is the case with the U-shaped groove of FIGS. 15-17, but instead of the U-shape they are completely solid thereby leaving no holes or irregularities in the distal surface 313 of the convex supporting device. The solid stiffening elements 312 may, however, still be relatively soft or resilient so that their contribution to the bending resistance of the convex supporting device in the horizontal bending direction is negligible.

(84) The stiffening elements 312 may not only reduce the risk of the supporting element 300 collapsing onto a protruding stoma, they may also reduce the risk or effectively prevent that the pressure force from the peristomal skin causes the base plate with the convex supporting device to “turn inside-out” and/or consequently dislodge from the body. In the event that the ostomate subjects his/her body to a more extreme movement (such as reaching high or deep down, or during physical exercise), the pressure force from the peristomal skin area on the base plate may momentarily rise to a higher level than in the normal wear situation and may consequently push the base plate away from the body in the peristomal area. As the base plate is adhered to the body over a larger area than what corresponds to the peristomal skin area, the result may be that the base plate with the convex supporting device flips or “turns inside-out” in the peristomal area, but remains attached at the edge. This is of course not desirable as it would almost certainly lead to leakage and a need to change the product. To avoid this situation, the described solid stiffening elements 312 may be comprised in the convex supporting device.

(85) In order to accommodate sunken or retracted stomas, the supporting member has a convex shape, which can be seen in FIG. 16. Basically, when referring to a convex shape or element in respect of ostomy devices reference is often made to an insert or an element where the two outer edges, e.g. the outer edge 303 and inner edge 304 of example 2, are displaced axially along the centre axis C-C, which also corresponds to the axis along which the stoma extends longitudinally when the ostomy appliance is worn.

Example 3

(86) Example 3 relates to a base plate for an ostomy appliance comprising an adhesive wafer for adhering to the skin surrounding a stoma, the base plate comprising a supporting element attached to the distal side of the adhesive wafer, the supporting element comprising a proximal annular element for placing around the stoma and at least two supporting arms extending radially from the outer edge of the proximal annular element and extending axially from the proximal annular element in the distal direction.

(87) This provides a base plate which provides support around the stoma and support in a relevant, desired skin area to provide increased comfort and security.

(88) Thus, in a specific version of example 3, two supporting arms extend diametrically opposite from the proximal annular element. This allows for a wearer to bend around the supporting arms without experiencing discomfort, while at the same time it decreases the risk of the base plate unintentionally folding in other directions. By the diametrically opposite extension of the supporting arms is to be understood that each of the arms extend radially away from the proximal annular element to which they connect.

(89) An embodiment of the example concerns a base plate for an ostomy appliance comprising an adhesive wafer for adhering to the skin surrounding a stoma, the base plate comprising a supporting element attached to the distal side of the adhesive wafer, the supporting element comprising a proximal annular element for placing around the stoma and at least two supporting arms extending radially from the outer edge of the proximal annular element and extending axially from the proximal annular element in the distal direction.

(90) Another embodiment of the example concerns a base plate comprising two supporting arms extending diametrically opposite from the proximal annular element.

(91) Details of Example 3

(92) FIG. 19 shows a supporting element 400, and FIGS. 20 and 21 show a base plate 401 formed of an adhesive wafer 407 and the supporting element 400. The adhesive wafer 407 has an adhesive 402 disposed on a backing layer 403 so that the adhesive wafer has an adhesive proximal surface and a non-adhesive distal surface.

(93) The supporting element is attached to the non-adhesive distal surface by e.g. gluing or welding. The adhesive wafer 407 is formed with a first through-going hole 406 and the supporting element has a second through-going hole 408. The adhesive wafer and the supporting element are aligned so that the first and second through-going holes are coaxially aligned along a central axis C-C. This allows for a stoma to be received by the base plate 401.

(94) The supporting element is formed by an inner annular ring 409, which provides support and stability to the skin area encircled by the ring which corresponds to the second through-going hole 408.

(95) Two arms 410, 411 extend on opposite sides of the inner annular ring 409. The arms allow for flexibility when the base plate is folded or bent around the respective arms but have or incur a higher stiffness or rigidity if the base plate is folded or bent transversely to the extent of the respective arms.

(96) In order to provide additional support, the arms also extend in an axial direction, i.e. along or parallel to the central axis C-C defined by the two through-going holes 406, 408. This provides arms that slant in an axial direction and thereby provides axial stability to the base plate.

(97) In order to attach a collecting bag to the base plate in the event of a 2-piece product, a coupling ring 412 is shown attached to the distal side of the adhesive wafer.

(98) It should be understood that the arms can have numerous shapes and configurations. For example, in one embodiment, the two or more supporting arms are provided in a bifurcated configuration extending from the proximal annular element. This allows for an even further differentiated effect of the supporting element, while still providing increased comfort and security in a desired, relevant skin area. Consequently, the ability of the supporting element to resist bending and/or axial compression can be differentiated according to user needs.

Example 4

(99) Example 4 relates to a convex shell for use in a base plate of an ostomy appliance, the convex shell comprising an annular ring defined by an outer edge and an inner edge defining a through-going hole, said annular ring comprising a first and second half defined by a folding axis A-A, which is perpendicular to the centre axis C-C of the through-going hole, wherein the convex shell comprises first folding restriction means for altering the flexibility of the convex shell when the first half is folded toward the second half around the folding axis A-A.

(100) Having a flexibility that can change depending on the folding angle, it is possible to provide an ostomy device which is soft and comfortable when regular movement of the body occurs, but where it is possible to prevent that the skin area around the stoma collapses in outer, or extreme, movement positions.

(101) Thus, for example, the first folding restriction means provides a first flexibility when the angle between the first and second half is between 180 and 90 degrees and a second flexibility when the angle between the first and second half is between 90 and 20 degrees, wherein the first flexibility is lower than the second flexibility.

(102) In this context, the phrase “lower” in regard to flexibility should be understood such that the resulting reactive force of the convex shell when the folding angle between the first and second half is between 180 and 90 degrees is less than the resulting reactive force of the convex shell when the folding angle between the first and second half is between 90 and 20 degrees.

(103) Accordingly, as long as the movement of the body folds the ostomy device in the range of the first folding angle then the ostomy device will be comfortable to wear and follow the movement of the body. However, if movement results in the ostomy device being folded in the range of the second folding angle, the ostomy device will provide a reinforced stiffness to the area around the stoma providing stability to the peristomal area.

(104) More specifically, the first folding restriction means may be in the form of at least one groove extending along the first axis, said groove having two opposite contact surfaces which are able to abut each other when the convex shell is folded, or bent, to a predetermined degree around the first axis.

(105) This provides a high flexibility as long as the two opposite contact surfaces are not abutting each other. However, if a fold, or bending movement of the user, causes the two contact surfaces to abut, the force required to further fold, or bend, the convex shell increases considerably providing a high stiffness and support around the stoma.

(106) The first folding restriction means on the convex shell may be placed on either side of the annular ring, i.e. both on the side facing the ostomist when the product is in use and/or on the side facing away from the ostomist.

(107) In embodiments wherein the first folding restriction means is/are placed on the side facing the user, there may be provided a distance between the convex shell and the base plate of the ostomy appliance in the area between the inner and the outer edge of the annular ring, thus creating a volume between the two parts when the annular ring is attached to the base plate of the ostomy appliance at said edges. Furthermore, or alternatively, there may be extra adhesive material in the base plate over at least some of the base plate area situated between the inner and outer edge of the annular ring.

(108) These features ensure that the flexibility of the base plate is maintained because the adhesive material of the base plate can deform, e.g. stretch and/or follow the body movements of the user independently of the characteristics of the convex shell in that area.

(109) An embodiment of the example concerns a convex shell for use in a base plate of an ostomy appliance, the convex shell comprising an annular ring defined by an outer edge and an inner edge defining a through-going hole, said annular ring comprising a first and second half defined by a folding axis A-A, which is perpendicular to the centre axis C-C of the through-going hole, wherein the convex shell comprises first folding restriction means for altering the flexibility of the convex shell when the first half is folded toward the second half around the folding axis A-A.

(110) Another embodiment of the example concerns a convex shell, wherein the first folding restriction means provides a first flexibility when the angle between the first and second half is between 180 and 90 degrees and a second flexibility when the angle between the first and second half is between 90 and 20 degrees, and wherein the first flexibility is lower than the second flexibility.

(111) Another embodiment of the example concerns a convex shell, wherein the first folding restriction means is in the form of at least one groove extending along the first axis, said groove having two opposite contact surfaces which are able to abut each other when the convex shell is folded to a predetermined degree around the first axis.

(112) Details of Example 4

(113) A convex shell 500 for use in a base plate (not shown) for attaching an ostomy collecting pouch to a user's body is shown in FIGS. 22 and 23.

(114) The convex shell 500 comprises an outer planar surface 502 extending in a first plane perpendicular to the centre axis C-C of a through-going hole 503 formed in the convex shell 500 for receiving the stoma, the outer planar surface 502 extending radially inwards from the outer edge and transitioning into an intermediate slanting surface 504. The intermediate slanting surface 504 extends radially inwards from the outer planar surface 502 towards an inner planar surface 505. The inner planar surface 505 extends in a second plane perpendicular to the centre axis C-C of the through-going hole 503 and extends radially from the intermediate slanting surface 504 towards an inner edge 506 of the convex shell 500 which defines the through-going hole 503.

(115) Six folding restriction means 507 are formed as respective grooves 508 extending transversely across the convex shell 500 from the inner planar surface 505 to the outer planar surface 502. Each groove has a first and a second groove wall 508′, 508″ defining a folding angle α.

(116) When the convex shell 500 is folded, or bent, around the folding axis A-A, which is perpendicular to the centre axis C-C, e.g. when a user bends, the two halves of the convex shell defined by the folding axis A-A will fold towards each other. At the same time, the groove walls 508′ and 508″ will also fold towards each other. This results in the folding angle α becoming smaller. At one point, if folded, or bent, to a certain extent, the groove walls 508′ and 508″ will contact each other when the folding angle reaches zero. At this point, the force required to fold or bend the convex shell 500 will increase considerably as the force needed to fold the convex shell also has to compress the material of the convex shell in order to fold it further.

(117) Understanding that the material of the convex shell 500 affects the folding considerably when the two groove surfaces 508′, 508″ come into contact enables the skilled person to modify the flexibility or bending resistance of the convex shell in order to suit specific needs by using different materials having different compressible characteristics.

(118) Should it be desirable to change the flexibility in further intervals the six grooves in the convex shell can be formed so that the respective groove walls have different angles between them. Thus, when grooves having one angle abut, the stiffness is increased slightly, and when grooves having a larger initial angle abut, the stiffness will increase even further.

(119) A convex shell 600 having numerous restriction means 607 is shown in FIG. 24. The restriction means are in the form of grooves 608, where a number of first grooves 609 extend in one direction across the convex shell and a number of second grooves 610 extend in another direction transverse to the direction of the first grooves.

Example 5

(120) Example 5 relates to a convex shell for use in a base plate of an ostomy appliance, the convex shell comprising an annular ring defined by an outer edge and an inner edge defining a through-going hole, said ring further comprising at least four transition sections extending transversely across the annular ring, dividing the annular ring into at least a first, second, third and fourth segment.

(121) From the term it should be understood that a ‘transition section’ is a section wherein the characteristics between two neighbouring segments of the convex shell changes.

(122) By changing the characteristics of the convex shell in such sections, it is possible to control the bending of the shell and, as will be described herein, it will be possible to keep the area around the stoma more stable and resistant towards collapsing, while providing improved flexibility in the peristomal area for better comfort.

(123) The transition sections can be provided as grooves.

(124) The first, second, third and fourth segments can be arranged symmetrically. This can for example be done by arranging the first and third segments opposite each other, and the second and fourth segments opposite each other.

(125) The first and third segments may have a higher thickness than the second and fourth segments. This is an additional and/or alternative way to control the bending. This results in that the convex shell will tend to bend in the transition sections where the thickness changes.

(126) Alternatively, the first and third segments may be formed by a different material than the second and fourth segments, which is another way to control the bending.

(127) Alternatively or additionally, the second and fourth segments may have a higher flexibility than the first and third segments.

(128) Details of Example 5

(129) The convex shell 700 of FIG. 25 comprises an annular ring 705 defined by an outer edge 706 and an inner edge 707. The inner edge 707 defines a through-going hole 708 which has an axis C-C. Furthermore, when considering the convex shell along the axis C-C of the through-going hole 708, the convex shell is symmetrical around axes A-A and B-B, which are perpendicular to each other.

(130) In use, the convex shell will preferably be applied on a user so the axis A-A will be mainly vertical and the axis B-B will be mainly horizontal when a user is standing. Or, in other words, the convex shell will be applied so that the natural movements of the user will cause the convex shell, and thereby the convex skin plate, to bend around the axis B-B.

(131) Four transition sections, formed as first, second, third and fourth grooves 710,711,712,713 extend transversely across the annular ring. The grooves divide the annular ring into at least a first segment 715 defined by the first and second grooves; a second segment 716 defined by the second and third grooves; a third segment 717 defined by the third and fourth grooves; and a fourth segment 718 defined by the fourth and first grooves.

(132) A hole 720 is provided in the backing layer 702 and adhesive 703 which is coaxially aligned with the through-going hole 708 of the convex shell.

(133) As can be seen in FIG. 26, the first groove 710 extends along an axis i-i and the fourth groove 713 extends along an axis ii-ii. In a similar way, although not shown, the second groove 711 extends along the axis i-i, and the third groove 712 extends along the axis ii-ii.

(134) It is to be understood that the features and principles of the presented examples of the application can be applied individually or in any suitable combination to make a convex supporting device for the base plate according to the invention.

Example 6

(135) Experimental Part

(136) A number of bendability, or folding, resistance and axial compression resistance tests according to the described test methods were carried out on a number of products presently commercially available on the market and on the applicant's products according to the invention. The products and the test results are presented and compared in the following. The bendability and compression tests were carried out on a texture analyser TA.XT Plus, serial number 10663 from Texture Technologies using 1, 5 and 30 kg load cells in an air-conditioned laboratory at a constant temperature of 23 degrees Celsius and at constant 50% RH.

(137) Products Tested:

(138) B.Braun Softima 1-piece ileostomy Roll-Up w/convex appliance, pre-cut hole Ø30 mm

(139) Coloplast SenSura Convex Light appliance, pre-cut hole Ø15 mm-Ø33 mm(max)

(140) Convatec Esteem 1-piece ileostomy Invisiclose w/convex appl., pre-cut hole Ø32 mm

(141) Dansac Nova 1, 1-piece closed colostomy appliance w/convex, pre-cut hole Ø28 mm

(142) Hollister Moderma Flex 1-piece urostomy appliance w/convex, pre-cut hole Ø15 mm

(143) Salts Confidence 1-piece colostomy appliance w/convex, pre-cut hole Ø28 mm

(144) Welland Flair 1-piece colostomy appliance w/convex, pre-cut hole Ø29 mm

(145) Prototype products with convex supporting device A, B, C, D, E and F.

(146) The material for the convex supporting device of the prototype products is preferably primarily a polyethylene-based material, such as, but not limited to, Engage 8401® or Engage 8402® which are both polyolefin elastomers in the form of ethylene-octene copolymer from Dow Chemical or Flexirene®, a linear low density polyethylene (LLDPE) from Polimeri Europa. To further control characteristics, e.g. resiliency of the convex supporting device, additional materials such as, but not limited to, EVA copolymers e.g. Escorene® grades from ExxonMobil Chemical may be added.

(147) The convex supporting device is produced by a classic plastic injection moulding process. Polymer material is fed into a heated barrel, mixed, and forced into a mould cavity where it cools and hardens to the configuration of the cavity. The backing layer, adhesive and release liner is further shaped to a convex shape to match the convex supporting device. The convex supporting device is placed on the backing layer and heat welded thereto at the outer and inner perimeter of the shell (corresponding to first and second attachment zones). During the heat welding process the convex supporting device and the backing layer are merged together as a result of pressure, heat and time.

(148) Prototypes A and C are a base plate comprising a convex supporting device based on the principles of example 5 having an axial distance between the inner and outer edges of the annular ring measured along the central axis C-C of 7 mm.

(149) Prototypes B and D are a base plate comprising a convex supporting device based on the principles of example 4 having an axial distance between the inner and outer planar surfaces of the convex shell measured along the central axis C-C of 9 mm.

(150) Prototypes E and F are a base plate comprising a convex supporting device based on the principles of examples 4 and 5 in combination, the transition sections of example 5 being provided on the distal side of the convex supporting element and the folding restriction means of example 4 being provided on the proximal side of the convex supporting device. The axial distance between inner and outer edges of the annular ring of the convex shell measured along the central axis C-C is 9 mm.

(151) The tests were carried out on two test specimens of each type of the products A, B, C and D and on one test specimen of types E and F (see additional comment in table 1 regarding Hollister Moderma Flex). The tested specimens did not include a release liner on the adhesive surface of the base plates. A very thin sheet of paper towel was applied to the adhesive surface in order to avoid unintentional adherence. The contribution to the bending and axial compression resistances, respectively, from this very thin and flexible component, are disregarded. Tables 1 and 2 show results of the axial compression test and the bendability test, respectively.

(152) TABLE-US-00001 TABLE 1 Load [N] Average Load [N] Load [N] 3 mm peak Standard Test Specimen 1 mm 2 mm Compression compression Standard deviation Product Compression Compression (peak load) load [N] deviation [%] B. Braun Softima 8.353 33.453 54.046 55.50 1.45 3 Specimens 1 & 2 5.440 27.280 56.949 Coloplast SenSura 4.683 9.530 13.265 12.68 0.58 5 Convex Light 3.402 8.351 12.100 Specimens 1 & 2 Convatec Esteem 10.430 33.019 52.841 54.93 2.08 4 Specimens 1 & 2 15.991 37.637 57.010 Dansac Nova 7.115 17.336 21.607 21.52 0.09 0 Specimen 1 &2 5.131 15.667 21.436 Hollister Moderma 10.411 51.236 51.236 *) — — Flex Specimen 1 *) Max compr. load of equipment reached, specimen 2 not tested Salts Confidence 3.777 24.023 43.379 48.73 5.35 11  Specimens 1 & 2 15.996 38.172 54.084 Welland Flair 8.854 33.570 49.451 47.60 1.85 4 Specimens 1 & 2 9.018 32.508 45.747 Prod A Specimen 1 5.556 14.993 23.365 23.59 0.23 1 Prod A Specimen 2 5.579 15.267 23.820 Prod B Specimen 1 4.142 13.688 20.688 21.20 0.52 2 Prod B Specimen 2 6.185 15.159 21.720 Prod C Specimen 1 8.748 37.303 64.476 57.19 7.29 13  Prod C Specimen 2 1.709 22.879 49.898 Prod D Specimen 1 3.851 9.212 13.387 13.43 0.04 0 Prod D Specimen 2 3.159 8.974 13.472 Prod E Specimen 2.105 9.343 15.642 15.64 — — Prod F Specimen 4.812 11.239 16.741 16.74 — —

(153) TABLE-US-00002 TABLE 2 Load Average [N] at bending Standard Test Specimen 20 mm load Standard deviation Product bending [N] deviation [%] B. Braun Softima Specimen 1 8.40 7.94 0.455 6 B. Braun Softima Specimen 2 7.50 Coloplast SenSura Convex 9.20 8.20 1.008 12 Light Specimen 1 Coloplast SenSura Convex 7.19 Light Specimen 2 Convatec Esteem Specimen 1 15.09 15.55 0.462 3 Convatec Esteem Specimen 2 16.01 Dansac Nova Specimen 1 16.31 16.22 0.093 1 Dansac Nova Specimen 2 16.13 Hollister Moderma Flex 18.56 19.14 0.577 3 Specimen 1 Hollister Moderma Flex 19.72 Specimen 2 Salts Confidence Specimen 1 4.78 4.80 0.027 1 Salts Confidence Specimen 2 4.83 Welland Flair Specimen 1 2.27 2.35 0.074 3 Welland Flair Specimen 2 2.42 Product A Specimen 1 1.60 1.59 0.005 0 Product A Specimen 2 1.59 Product B Specimen 1 1.62 1.64 0.027 2 Product B Specimen 2 1.67 Product C Specimen 1 1.494 1.45 0.05 3 Product C Specimen 2 1.399 Product D Specimen 1 1.11 0.95 0.164 17 Product D Specimen 2 0.78 Product E Specimen 2.09 2.09 — — Product F Specimen 2.17 2.17 — —

(154) As it may be derived from table 1 above, all of the tested products and prototypes have an average peak compression load, i.e. an axial compression resistance of between more than 12 Newtons to more than 50 Newtons corresponding to the products ranging from being relatively compressible, but still able to maintain a necessary peristomal pressure, to very rigid and practically inflexible in the axial direction.

(155) Table 2 shows the average bending load, i.e. the resistance to bending of the products and prototypes. As seen in the table, all of the applicant's prototypes exhibit an average bending load below 2.25 Newton meaning that the prototypes are relatively flexible.

(156) Some bendability resistance may be needed to avoid collapse of the peristomal skin area. Thereby, the bendability resistance preferably ranges between 0.8 N and 2.25 N.

(157) When conjoining the values of tables 1 and 2 as expressed in FIG. 27 (and schematically indicated in FIG. 8), it is clear that the new technology according to the invention comprises the only product types that offer a comfortable level of bending resistance and security against peristomal collapse while simultaneously maintaining the necessary peristomal pressure to let the stoma protrude and reducing the risk of pressure ulcers significantly. In other words, in the present application it is realized that the prior art convex ostomy devices exert an unnecessary high pressure to the peristomal skin in order to achieve the beneficial effects of such convex devices namely to ensure that the stoma protrudes correctly and sufficiently into the collecting bag to prevent stomal output from leaking under the base plate as previously discussed. With the base plate according to the present invention, the same benefits are achieved only with a lower peristomal skin pressure reducing the risk of pressure ulcers.

(158) Moreover, it is also realized by the present invention that the base plate does not need to have a high bending resistance, i.e. be very stiff, to maintain the necessary pressure on the peristomal skin. Indeed, another significant benefit of this invention is therefore also that a more skin friendly and less aggressive adhesive may be used to secure the convex appliance to the user's body than with the prior art convex devices. When applying the much more flexible base plate according to the invention on the skin, less adhesive force is required to make it stay in place because according to the invention the skin may now follow the user's body movements. This is contrary to the prior art products where the beneficial effects of the convex products are achieved by the high stiffness of the products forcing the skin to avoid collapse, but simultaneously compromising the product's ability to follow body movements and thus compromising the flexibility of the product. As less adhesive force is required to secure the base plate of the invention to the skin, it means that the adhesive may be more skin friendly because a weaker adhesive will, among other effects, result in less skin cell stripping upon removal of the product from the skin.

(159) A particular advantage of the products of the invention is that with a base plate according to the various possible embodiments of the present invention having a bending resistance of 2.25 N or less when the product is bent 20 mm and an axial compression resistance of more than 10 N at 3 mm compression, products are achieved that will stay on the body for an increased time of wear because of the ability to better follow the body movements. The products are changed less often due to leakage. And when leakage occurs, the area of the adhesive affected is remarkably less. On top of these hard-core features, the users felt more free and comfortable with the flexible products.

(160) It will be appreciated that individual user needs may determine how a product is designed according to the many possible combinations of the present invention. One user may need a product with a relatively high axial compression resistance while another user may need a product with a relatively moderate axial compression. With the present invention, products are obtained that provide these possibilities without compromising the comfort of a flexible, yet secure product.