Ostomy pouch

Abstract

An ostomy pouch having a cavity for storing stomal output. The cavity is defined by a rear wall and a front wall joined at their peripheries and formed of flexible sheet material. The ostomy pouch further comprises a sheet of woven comfort material covering the outside surface of the front wall. The sheet of comfort material has an outside surface and an opposite inside surface, and the outside surface of the sheet of comfort material forms at least part of the outside surface of the pouch. The inside surface of the sheet of comfort material is laminated across its entire surface to a continuous layer of film material. At least part of the continuous layer of film material is adjacent, facing and unbonded to the outside surface of the front wall.

Claims

1. An ostomy pouch comprising a cavity for storing stomal output; the cavity defined by a rear wall and a front wall joined at their peripheries and formed of flexible sheet material; the ostomy pouch further comprising a sheet of woven comfort material covering the outside surface of the front wall; the sheet of comfort material having an outside surface and an opposite inside surface, wherein the outside surface of the sheet of comfort material forms at least part of the outside surface of the pouch, and the inside surface of the sheet of comfort material is laminated across its entire surface to a continuous layer of film material, with no intervening adhesive; the continuous layer of film material having no voids, and at least part of the continuous layer of film material being adjacent, facing and unbonded to the outside surface of the front wall.

2. An ostomy pouch according to claim 1 wherein the continuous layer of film material has an even thickness across the entire surface of the sheet of woven comfort material.

3. An ostomy pouch according to claim 1 wherein the continuous layer of film material has thickness of less than 40 microns across the entire surface of the sheet of woven comfort material.

4. An ostomy pouch according to claim 1 wherein the continuous layer of film material has an area density of 18-30 g/m.sup.2.

5. An ostomy pouch according to claim 1 wherein the continuous layer of film material is formed of the same material as the front wall and the rear wall.

6. An ostomy pouch according to claim 1 wherein the continuous layer of film material and the front and rear walls are formed of polymers with the same chemical structure.

7. An ostomy pouch according to claim 1 wherein the continuous layer of film material and the front and rear walls are formed of polymers with the same molecular weight M.sub.n.

8. An ostomy pouch according to claim 1 wherein the continuous layer of film material and the front and rear walls are formed of polymers obtained from the same source, with the same designation.

9. An ostomy pouch according to claim 1 wherein the continuous layer of film material is formed of EVA.

10. An ostomy pouch according to claim 9 wherein the front and rear walls are formed of EVA.

11. An ostomy pouch according to claim 1 wherein the continuous layer of film material has an area density of at least 5 g/m.sup.2, and no more than 50 g/m.sup.2.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) 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:

(2) FIG. 1 is a rear view of an ostomy pouch.

(3) FIG. 2 is a front view of the ostomy pouch of FIG. 1.

(4) FIG. 3 is a cross-sectional side view of the ostomy pouch of FIG. 1.

(5) FIG. 4 is a front view of an alternative ostomy pouch.

(6) FIG. 5 is a cross-sectional side view of the ostomy pouch of FIG. 4.

(7) FIG. 6 is an exploded perspective view of the ostomy pouch of FIG. 4.

(8) FIG. 7 is a side view of an apparatus for producing an ostomy pouch.

(9) FIG. 8 is a partial view of an ostomy pouch according to any of the embodiments of FIGS. 1-8 showing the absence of leakage of the laminated film layer through the woven comfort material in the region where the comfort material is bonded to the cavity; and

(10) FIG. 9 is a partial view of a an ostomy pouch with layer of comfort material manufactured in accordance with a prior art method, showing the leakage of the hot melt adhesive through the woven comfort material in the region where the comfort material is bonded to the cavity.

(11) Unless defined otherwise, all technical and scientific terms used in this specification have the same meaning as is commonly understood by the reader skilled in the art to which the claimed subject matter belongs. It is to be understood that the foregoing summary of the disclosure and the following examples are exemplary and explanatory only and are not restrictive of any subject matter claimed.

(12) The following description is directed to embodiments of the disclosure. The description of the embodiments is not meant to include all the possible embodiments of the disclosure that are claimed in the appended claims. Many modifications, improvements and equivalents which are not explicitly recited in the following embodiments may fall within the scope of the appended claims. Features described as part of one embodiment may be combined with features of one or more other embodiments unless the context clearly requires otherwise.

(13) In this specification, the use of the singular includes the plural unless the context clearly dictates otherwise. In this application, the use of or means and/or unless stated otherwise. Furthermore, use of the term including as well as other forms, such as include, includes, and included, is not limiting.

(14) As used herein, ranges and amounts can be expressed as about a particular value or range. About also includes the exact amount. For example, about 5 mm means about 5 mm and also 5 mm. Generally, the term about includes an amount that would be expected to be within experimental error. The term about includes values that are within 5% less to 5% greater of the value provided. For example, about 30 mm means between 28.5 mm and 31.5 mm.

(15) Referring to FIGS. 1 to 3, an embodiment of the invention is shown in which an ostomy pouch 1 comprises a rear wall 2, a front wall 3, a separation wall 4, a rear comfort layer 5, a front comfort layer 6 and an ostomy wafer 7. In other embodiments within the ambit of the invention as claimed, one or more of the separation wall 4, the rear comfort layer 5 and the front comfort layer 6 may be omitted if desired.

(16) In this embodiment, the ostomy pouch 1 is a one-piece pouch wherein the ostomy wafer 7 is permanently attached to the ostomy pouch 1 (in the sense that it cannot be easily removed and re-attached without damaging the pouch). However, other embodiments may be a two-piece pouch comprising a pouch component and body fitment component that together form the ostomy pouch. In some of these embodiments, the pouch comprises the rear wall 2, the front wall 3, the separation wall 4, the rear comfort layer 5 and the front comfort layer 6, and the body fitment component comprises the ostomy wafer 7.

(17) The rear wall 2 and the front wall 3 define a cavity for containing a stomal output. In this embodiment, the rear wall 2 and the front wall 3 are both formed of flexible sheet material in the form of a plastics film and are joined together to define the cavity. An exemplary film is Ethylene-vinyl acetate (EVA). The film typically has a thickness of 75 to 100 m but in some embodiments may have a thickness of 50 to 150 m.

(18) In this embodiment, the ostomy pouch 1 has an upper section 10, a lower section 11 and a waisted section 12 that is located between the upper section 10 and the lower section 11. The upper section 10 has a maximum width, A, the lower section 11 has a maximum width, B, and the waisted section, 12, has a minimum width, C. In this embodiment, the maximum width, A, of the upper section 10 is greater than the maximum width, B, of the lower section 11, which in turn is greater than the minimum width, C, of the waisted section 12.

(19) In this embodiment, the ostomy pouch 1 has a left-hand 13 and right-hand 14 edge when viewed from the rear. The waisted section 12 has a left-hand edge 13c and a right-hand edge 14c that are both smoothly rounded and merge into the respective left-hand edges 13a, 13b and right-hand edges 14a, 14b of the upper section 10 and the lower section 11.

(20) The shape and dimensions of the ostomy pouch 1 are not particularly limited so long as it remains discreet and comfortable to wear in use. Exemplary dimensions and other suitable shapes are set out in the prior art documents cited in the introduction, such as PCT/GB2021/051340, which is incorporated by reference.

(21) In this embodiment, the left-hand edge 13c and the right-hand edge 14c of the waisted section 12 have concave curvature with a radius of curvature, r1.

(22) In this embodiment, both the upper 10 and lower 11 sections are rounded and comprise continuously curved edges 15, 16 respectively. The curved edges 15, 16 extend from the upper and lower ends of left-hand edge 13c of the waisted section 12 to the corresponding upper and lower ends of the right-hand edge 14c of the waisted section 12. The edges 15, 16 are convexly curved with a radius of curvature of r2 and r3 respectively. In this embodiment, the r2 and r3 are constant along their respective edges 15, 16, however in alternative embodiments they may be variable.

(23) In this embodiment, the upper section edge 15 incorporates the left-hand edge 13a and the right-hand edge 14a of the upper section 10 while the lower section edge 16 incorporates the corresponding left-hand 13b and right-hand edge 14b of the lower section.

(24) In this embodiment, a junction between the upper section 10 and the waisted section 12 may be demarcated by a single point of inflection 17 between the edges 13a, 14a of the upper section 10 and the edges 13c, 14c of the waisted section 12. Similarly, a junction between the lower section 11 and the waisted section 12 may be demarcated by a single point of inflection 18 between the edges 13b, 14b of the lower section 11 and the edges 13c, 14c of the waisted section 12.

(25) The rear wall 2 and front wall 3 are joined around their peripheral edges by use of welding. Welding is a preferred method of joining the rear wall 2 and the front wall 3 as it allows all the layers of the pouch 1 to be joined simultaneously, as described later.

(26) In this embodiment, the rear wall 2 and the front wall 3 are joined together by a single continuous edge seal 8 that extends around a full perimeter of the rear wall 2 and the front wall 3 to create a fluid-tight seal.

(27) The rear wall 2 is provided with a stomal inlet 20 for receiving the stomal output into the cavity. The stomal inlet 20 is an aperture that is cut out of the rear wall 2 in the upper section 10 of the ostomy pouch 1, in which the wafer 7 is provided, the wafer having a hole through which a stoma normally extends.

(28) In this embodiment, the rear comfort layer 5 and front comfort layer 6 are substantially the same shape as the rear 2 and front 3 walls. The rear 5 and front 6 comfort layers form the outside of the ostomy pouch 1 and cover the rear 2 and front 3 walls respectively. The rear comfort layer 5 also comprises a wafer aperture that is in register with the stomal inlet 20 of the rear wall 2, in which the wafer 7 is arranged.

(29) The rear comfort layer 5 and the front comfort layer 6 are formed of a flexible sheet material comprised of a woven fabric layer which is laminated across its entire surface to a continuous layer of film material. The continuous layer of film material forms an uninterrupted, solid layer having no voids, thus completely covering one surface of the comfort layer 6, namely its inside surface in use.

(30) In this embodiment, the fabric layer forms the outside surface of the rear 5 and front 6 comfort layers respectively, with the continuous layer of film material disposed on the corresponding inside surfaces, facing the rear 2 and front 3 walls. Other embodiments may comprise additional fabric layers and/or film layers as required. In this embodiment, the woven fabric layer comprises polyester but in other embodiments any one or more of nylon, viscose, polyethylene and polypropylene could be used in addition or as an alternative.

(31) In this embodiment, the woven fabric layer has an area density of 58 g/m.sup.2, a tensile strength of 280 to 300 N, and a tear strength of 18 N. Other embodiments may have different compositions, for example an area density of 50 to 70 g/m.sup.2, a tensile strength of 200 to 400 N, and a tear strength of 10 to 30 N. Some embodiments may also have a colour fastness to any one or more of rubbing, perspiration or washing (40) of 4 to 5, and an abrasion of >50,000. Certain embodiments also comprise a woven polyester with a water repellent finish. The water repellent finish may be fluorocarbon based and may be dyed heat set or boil off heat set. A suitable woven polyester layer is available from Newton Textiles Limited of Northamptonshire, UK, under the 75DCWR Designation, such as 75DCWRWHITE (for a white variant).

(32) In this embodiment, continuous layer of film material comprises ethylene-vinyl acetate (EVA).

(33) In this embodiment, the continuous layer of film material has an area density of 23 g/m.sup.2. A suitable EVA film is available from Protechnic SA of Cernay, France under the designation 3X9S23.

(34) The continuous layer of film material is laminated to the fabric layer over the entire area of the inside surface of the rear 5 and the front 6 comfort layers. Lamination, e.g. calendaring at elevated temperature and pressure, creates a laminate in which the continuous layer of film material extends across the entire area of the comfort layers 5, 6 with an even thickness throughout and no voids therein. Because the EVA film in question is adhesive at elevated temperature, no intervening adhesive layer is between the continuous film and the comfort layer, rather, the continuous layer of film material is laminated directly to the comfort layer.

(35) Advantageously, the provision of the continuous layer of film material allows both comfort layers 5, 6 and both walls 2, 3 to be joined together simultaneously in the same welding process if desired, in the same manner as a non-woven material would be attached, improving the bond, without the need for specialist intervening layers or the application of adhesive during the construction process. In this embodiment, the peripheral weld defined by the edge seal 8 also joins the rear comfort layer 5 to the rear wall 2 and the front comfort layer 6 to the front wall 3. In other embodiments, various welds may be used as required or desired. For example, the weld may only correspond to a portion of the weld joining the rear 2 and front 3 walls. The weld attaching the rear comfort layer 5 to the rear wall 2 may be different from the weld attaching the front comfort layer 6 to the front wall 3. In addition, the continuous layer of film material protects the fabric layers from undesirable fraying.

(36) In this embodiment, the front comfort layer 6 comprises an upper part 6a and a lower part 6b, which when taken together are the same shape as the front wall 3. The upper 6a extends from the top of the pouch 1 to the point of inflection 17 between the upper section 10 and waisted section 12. The lower part 6b extends from the bottom of the pouch 1, beneath the upper part 6a to a point slightly above the point of inflection 17. As such, the upper 6a part partially overlaps the lower part 6b in an overlap region 115. The upper part 6a and the lower part 6b are separable from each other in the overlap region 115 to form a window opening for viewing the cavity. The overlap region 115 extends horizontally when the ostomy pouch 1 is in use. In some embodiments, the overlap region 115 may not coincide with the point of inflection 17 and may span the pouch 1 at any suitable location along its length. Importantly, without the presence of the continuous layer of film material, the two parts 6a, 6b, of the front comfort layer 6 would not bond to one another at all, regardless of the choice of material for the walls 2,3, because the material of the wall is not involved in the bond in that region.

(37) In other embodiments, the front layer may be comprised of multiple parts. The external shape and dimensions of the multiple parts when taken together may be the same as that of the front wall 3.

(38) In this embodiment, the ostomy wafer 7 is in register with the stomal inlet 20 of the rear wall 2 and extends through the wafer aperture of the rear comfort layer 5. The ostomy wafer 7 comprises an adhesive and a release liner 31. The ostomy wafer 7 is mounted to the rear wall 2 by welding. In other embodiments the wafer 7 may be mounted by any suitable alternative means (e.g. adhesive).

(39) The ostomy pouch 1 may also be provided with a gas vent for venting of stomal gases from the cavity. In this embodiment, the ostomy pouch 1 comprises a gas vent filter 24 which is also an odour filter. Suitable filters could be a charcoal or activated carbon filter, for reducing the release of unwanted odours from the cavity. The gas vent filter 24 forms a part of the gas vent, which comprises a gas vent aperture 27 located in the front wall 3. In some embodiments, the gas vent filter 24 is covered by a filter cap and the gas vent filter 24 and filter cap are located on the front wall 3 over the gas vent aperture 27. The gas vent aperture 27 permits the passage of gas from the cavity towards an exterior of the ostomy pouch through the gas vent filter 24 and filter cap.

(40) In this embodiment, the gas vent is located, in use, in the upper quarter of the ostomy pouch 1. In particular, the centre of the gas vent aperture 27 is disposed, in use, above the centre of the stomal inlet 20. In other embodiments, the gas vent may be located elsewhere in the upper section 10 of the ostomy pouch 1.

(41) In this embodiment, the separation wall 4 is located between the rear wall 2 and the front wall 3. The separation wall 4 comprises a separation filter 100 for filtering stomal gases and/or stomal liquids from stomal solids contained in the stomal output. The separation filter 100 thus prevents stomal solids from contacting the gas vent and clogging or otherwise impairing the functionality of the gas vent filter 24.

(42) In this embodiment, the separation wall 4 has the same external shape and dimensions as the rear wall 2 and the front wall 3 and divides the cavity of the ostomy pouch 1 into a first and a second chamber 101, 102. The first chamber 101 extends between the separation wall 4 and the rear wall 2, and the second chamber 102 extends between the separation wall 4 and the front wall 3. The first and second chambers 101, 102 have substantially the same volume. In other embodiments, they may have different volumes and/or the second chamber 102 may have a larger volume than the first chamber 101.

(43) In this embodiment, the separation wall 4 is joined to the rear wall 2 and front wall 3 at their peripheral edges by use of welding to create a fluid-tight seal therebetween. In another embodiment, the separation wall 4 is joined to the rear 2 and front 3 walls about the whole of the edge of the upper section 10, and is additionally joined to the front wall 3 by a horizontal weld at the interface between the upper 10 and waisted 12 sections. Therefore, the joining of the separation wall 4 with the rear and front walls 2, 3 according to some embodiments of the invention may be such that the first and second chambers 101, 102 are sealed from one another other than via the separation filter 100.

(44) In this embodiment, the separation wall 4 comprises a flexible sheet material, which may be formed of polyurethane, polyethylene (PE), polyvinylidene chloride (PVDC) and/or ethylene-vinyl acetate (EVA). In some embodiments, the flexible sheet material of the separation wall 4 has a thickness of 50 to 150 micrometres, preferably 75 to 100 micrometres. In this embodiment, the separation wall 4 comprises a hydrophobic and oleophobic coating applied to the flexible sheet material. In other embodiments, the flexible sheet material may be hydrophobic and/or oleophobic.

(45) Referring to FIGS. 4 to 6, a further embodiment of an ostomy pouch 201 according to the present invention is similar to that shown in FIGS. 1 to 3, with like features having similar reference numerals, incremented by 200. The main difference is that the lower section 211 of the further embodiment is shaped to accommodate/form a foldable drain. Thus, in contrast to the embodiments described above, this embodiment of the ostomy pouch 201 is an open pouch that does not comprise a sealed perimeter.

(46) Moreover, in this embodiment, no separation wall is provided between the front 203 and rear 202 walls, and as such the cavity is not divided into two sections. The rear wall 202 features a large opening 202i in register with the stomal inlet 207i of the wafer 207 (which is connected to the rear wall 202 in the region between the periphery of the opening 202i and the periphery of the wafer, such that stomal output enters the cavity via the stomal inlet of the wafer and the opening 202i in the rear wall. The rear comfort layer 205 also features an opening 205i slightly larger than the opening 202i in the rear wall 202 and in register with it, so as to be sandwiched between the outermost edge of the wafer and the rear wall 202. The stomal inlet 207i is adjustable to fit the stoma of the ostomate.

(47) In a similar fashion to the first embodiment, the front comfort layer 206 of this embodiment is formed of two parts: an upper part 206a; and a lower part 206b. The upper part 206a overlaps the lower part 206b across the majority of the width of the pouch 201 at a point on its height in register with the stomal inlet 207i. The overlap being defined by the lower edge 231 of the upper part 206a that overlaps the upper edge 232 of the lower part 206b.

(48) In this embodiment, there is also an optional gas filter 224 positioned in the front wall 203 at a height above the stomal inlet 207i to allow gas to exit the pouch 201. in this embodiment, the filter 224 is covered by an optional filter cover patch 225 (not shown in FIG. 5) on the outside surface of the front wall 203. As such, the filter 224 and filter cover patch 225 are covered by the upper part 206a of the front comfort layer 206.

(49) In this embodiment, the lower section 211 comprises a drain aperture 40. The drain aperture 40 is an unsealed portion of the perimeter of the ostomy pouch 201 where the rear 202 and front 203 walls are not scaled.

(50) In this embodiment, the lower section 211 comprises a rounded portion 211a and a substantially rectangular drain portion 41 that accommodates the drain aperture 40, with the rounded portion 211a being adjacent the waisted section 212 and the drain portion 41 being distal the waisted section 212. The drain portion 41 is foldable along its length between an unfolded and a folded configuration as described later.

(51) In this embodiment, the lower section 211 comprises a continuous left edge 42 that extends from the left edge 213c of the waisted section 212 to a left vertex 44 of the drain aperture 40 around the curved left edge 42c of the generally rounded portion 211a and along a left edge 42d of the drain portion 41. Similarly, a continuous right-hand edge 43 extends from the right edge 214c of the waisted section 212 to a right vertex 45 of the drain aperture 40 around a continuously curved right edge 43c of the generally rounded portion 211a and along a right edge 43d of the drain portion 41. (Note that as FIG. 4 is a front view, the left edges of the pouch 1 are on the right of the figure and right edges of the pouch 1 on the left of the figure.)

(52) The left 42d and right 43d edges of the drain portion 41 are parallel to one another along the majority of their length.

(53) In this embodiment, a single continuous edge seal 208 extends around the perimeter of the pouch 201 from the left vertex 44 of the drain aperture 40 to the right vertex 45 of the drain aperture 40, leaving the distal end of the drain aperture 40 open.

(54) In this embodiment, the drain portion 41 defines an elongate drain passage that extends from the cavity of the ostomy pouch 201 to the drain aperture 40 located at a lower end of the drain portion 41. The drain portion 41 is integral with the lower section 211 and as such, the rear wall 202 and the front wall 203 may each be a single piece of material that includes the upper section 210, the waisted section 212 and lower section 211 (including the drain portion 41). However, in this embodiment, the rear comfort layer 205 and front comfort layer 206 do not cover the drain portion 41 of the rear wall 202 and the front wall 203.

(55) In this embodiment, communication between the cavity and the elongate drain passage is via a drain inlet 200 defined as the point of transition between the cavity and the drain portion 41. The drain inlet 200 allows passage of stomal output from the cavity into the drain portion 41 when the drain portion 41 is unfolded.

(56) In this embodiment, movement of the drain portion 41 between its unfolded or folded configuration opens or closes the drain aperture 40. This either permits or prevents outflow of the stomal output stored in the ostomy pouch 1 cavity.

(57) In this embodiment, the drain portion 41 can be repeatedly folded in the same sense along its length into a plurality of segments having approximately equal segment lengths and separated by folds. The drain portion 41 may therefore be successively folded one or more times such that the segments overlie each other. Each fold is formed across the width of the drain portion 41 and acts to inhibit and preferably prevent passage of stomal output out of the drain aperture 40.

(58) In this embodiment, first 221 and second 222 pursing strips are provided on the drain portion 41. The pursing strips 221, 222 provide both localised rigidity to the drain portion 41 and also define the locations and orientations of the segments and folds of the drain portion 41. The pursing strips 221, 222 comprise strips of flexible material attached drain portion 41, wherein the strips 221, 222 have a higher rigidity than the material of the drain portion 41. The pursing strips 221, 222 also have some resilience such that once attached to the drain portion 41, the pursing strips 221, 222 can each be squeezed laterally to arch the pursing strip and thereby open the elongate drain passage. In other embodiments, two or more pursing strips may be used.

(59) In this embodiment, the pursing strips 221, 222 are formed from polystyrene, but other embodiments may comprise any suitable material.

(60) In this embodiment, the first pursing strip 221 is attached to the rear wall 202 of the drain portion 41 adjacent the drain aperture 40. The second pursing strip 222 is attached to the front wall 203 of the drain portion 41 above the second strip 222. A longitudinal gap is provided between an upper edge of the first pursing strip 221 and a lower edge of the second pursing strip 222. The longitudinal gap therefore defines the location of a first fold of the drain portion 41. Each pursing strips 221, 222 spans the width of the drain portion 41 and extends the same distance along a length of the drain portion 41.

(61) In this embodiment, a rear fastening element 215a is arranged on the rear wall 202 and a front fastening element 215b is arranged on a flap 223 that is mounted to the front comfort layer 206. In this example of a two-part front comfort layer 206, the flap 223 is mounted to the lower part 206b of the comfort layer 206. The rear fastening element 215a and the front fastening element 215b comprise corresponding hook-and-loop type fastener elements. The rear fastening element 215a is located on the drain portion 41 above the second pursing strip 222. A longitudinal gap is provided between an upper edge of the second pursing strip 222 and a lower edge of the rear fastening element 215a. The longitudinal gap therefore defines the location of a second fold of the drain portion 41.

(62) In this embodiment, the flap 223 comprises a first flange 223a and a second flange 223b formed of one integral piece. The first flange 223a spans substantially all of the width of the lower rounded section 211a, but does not extend over the edge seal 208, at a point one third up the length of the rounded section 211a from the drain inlet 200. The first flange 223a is attached to the comfort material 206 by a single weld that spans substantially its entire width.

(63) The flap 223 may be formed from the same material as the comfort layer, that is to say, a sheet of woven comfort material, with a continuous layer of film material laminated to its inside surface. A such, the weld between the outside surface of the comfort layer 206b to the flap 223 is made possible by the continuous layer of film material which forms the inside surface of the sheet of woven comfort material. The second flange 223b extends from the lower edge of the first flange 223a and is connected to the pouch 1 only by the first flange 223a. The second flange 223b is contoured so as to conform to the shape of the rounded portion 211a but is thinner, tracing the inside edge of the peripheral weld 208. As such, the second flange 223b extends downwards from the first flange 223a within the perimeter defined by the edge seal 208 of the pouch 201.

(64) In this embodiment, the flap 223 has an outside surface, facing away from the ostomate in use and an opposite inside surface. The front fastening element 215b is located on the inside surface of the second flange 223b at a position above the rear fastening element 215a. A longitudinal gap is provided between an upper edge of the rear fastening element 215a and a lower edge of the front fastening element 215b and defines the location of a third fold of the drain portion 41. The flap 223 is formed from a flexible sheet material that is more rigid than the flexible sheet material of the rear wall 202, front wall 203 and comfort layers 205, 206. In this embodiment, the flap 223 is formed from a plastic foam which provides a desirable rigidity.

(65) Folding of the drain portion 41 may be carried out as follows. First, the distal end of the drain portion 41 is folded upwards and away from the rear of the ostomy pouch 201 about the first fold line to locate the first pursing strip 221 over the second pursing strip 222. Secondly, the drain portion 41 and the pursing strips 221, 222 are folded again, in the same sense, about the second fold line and then the third fold line such that the folded and stacked first pursing strip 221, second pursing strip 222 and first fastening element 215a are located beneath the second flange 223b of the flap 223 with the rear fastening element 215a being exposed and adjacent the front fastening element 215b. Finally, the second flange 223b of the flap 223 is pressed onto the folded drain portion to secure together the rear fastening element 215a and the front fastening element 215b.

(66) In these embodiments, the drain portion 41 can then be unfolded by reversing the above procedure.

(67) As in the first embodiment, in the second embodiment, the rear comfort layer 205 and the front comfort layer 206 are formed of a flexible sheet material comprised of a woven fabric layer with a continuous layer of film material laminated to one surface-its inside surface in use. In this embodiment, the fabric layer is forms the outside surface of the rear 205 and front 206 comfort layers respectively, with the continuous layer of film material disposed on the corresponding inside surfaces, facing the rear 202 and front 203 walls. Other embodiments may comprise additional fabric layers and/or film layers as required. In this embodiment, the woven fabric layer comprises polyester but in other embodiments any one or more of nylon, viscose, polyethylene and polypropylene could be used in addition or as an alternative.

(68) In this embodiment, the woven fabric layer has an area density of 58 g/m.sup.2, a tensile strength of 280 to 300 N, and a tear strength of 18 N. Other embodiments may have different compositions, for example an area density of 50 to 70 g/m.sup.2, a tensile strength of 200 to 400 N, and a tear strength of 10 to 30 N. Some embodiments may also have a colour fastness to any one or more of rubbing, perspiration or washing (40) of 4 to 5, and an abrasion of >50,000. Certain embodiments also comprise a woven polyester with a water repellent finish. The water repellent finish may be fluorocarbon based and may be dyed heat set or boil off heat set. A suitable woven polyester layer is available from Newton Textiles Limited of Northamptonshire, UK, under the 75DCWR Designation, such as 75DCWRWHITE (for a white variant).

(69) In this embodiment, the continuous layer of film material has an area density of 23 g/m.sup.2. A suitable EVA film is available from Protechnic SA of Cernay, France under the designation 3X9S23.

(70) In this embodiment, the continuous layer of film material is once again laminated directly onto the fabric layer over an entire area of the inside surface of the rear 205 and the front 206 comfort layers, with no intervening adhesive required, because the film layer itself is adhesive at elevated temperatures.

(71) Advantageously, as in the first embodiment the use of the continuous layer of film material allows both comfort layers 205, 206 and both walls 202, 203 to be joined together simultaneously in the same welding process if desired, in the same manner as a non-woven material would be attached, without the need for specialist intervening layers or the application of adhesive during the construction process and with adhesion even in regions where woven layers are joined to each other (i.e. the overlap). In this embodiment, the peripheral weld defined by the edge seal 208 also joins the rear comfort layer 205 to the rear wall 202 and the front comfort layer 206 to the front wall 203. In other embodiments, various welds may be used as required or desired. For example, the weld may only correspond to a portion of the weld joining the rear 202 and front 203 walls. The weld attaching the rear comfort layer 205 to the rear wall 202 may be different from the weld attaching the front comfort layer 206 to the front wall 203.

(72) Referring to FIG. 7, apparatus for use in a method of forming the pouches of the invention is shown schematically. In this embodiment, an apparatus 300 comprises four rollers 301, 302, 303 and 304, a stamp welding machine 305, and a cutting machine 306. The rollers 301, 302, 303, 304 are used to advance a first 311, a second 312, a third 313 and a fourth 314 flexible sheet material respectively in the direction of the arrow, D. For simplicity, additional rollers used to advance the sheet material are not shown.

(73) In this embodiment, the apparatus 300 is configured to construct an ostomy pouch 310 similar to the ostomy pouches 1, 201 of FIGS. 1 to 6 comprising a rear comfort layer 5, 205, rear wall 2, 202, front wall 3, 203 and front comfort layer 6, 206. However, the process is shown simplified, without features such as the separation layer 4 or aspects of the drain portion 41 described in the embodiments above and without any description of the assembly of the wafer, filter and so forth, which can be provided in manner which will be well known to those skilled in the art.

(74) The first 311 and second 312 sheets of material are plastics film used for the rear and front walls of the pouch 310 respectively. As such, the materials used for these sheets are the same and correspond to that described in relation to the ostomy pouches 1, 201 described above.

(75) In this embodiment, the third 313 and fourth 314 sheets of material are used for the rear and front comfort layers of the pouch 310 respectively. As described above, the material used for the comfort layers comprise a woven fabric layer with a continuous layer of film material laminated thereto. As such, the third 313 and fourth 314 sheets of material comprise a woven fabric layers 313a, 314a each having a continuous layer 313b, 314b of film material laminated thereto. In FIG. 7, the layers of film material 313b, 314b face towards one another, with the first and second layers of sheet material 311, 312 which will form the rear and front walls of the cavity arranged between them.

(76) The third 313 and fourth 314 sheets of material have been previously formed in a separate facility, days earlier, by a laminating process, such as a calendaring process, in which a thin, but solid sheet of EVA film 313b, 314b (having no voids therein) is advanced from a roll and laminated under elevated heat and pressure directly onto sheet of woven material 313a, 313b similarly advanced from a roll, then cooled and rolled onto a new roll, on which it is delivered. As noted above, no intervening adhesive is provided between the solid sheet of EVA film and the sheet of woven material. This process creates a continuous layer of EVA film with an even thickness across the entire surface of the woven material and avoids the formation of any voids in the continuous layer of EVA film 313b, 314b. For example, with a laminate of EVA film is available from Protechnic SA of Cernay, France under the designation 3X9S23, on the woven comfort material, the entire surface can be covered by the laminate, and the thickness of the EVA film can be substantially unchanged from its starting thickness of a constant 23.2 m=/1 m across its entire length and width.

(77) In this embodiment, the stamp welding machine 305 is arranged to weld together the layers of material using a hot stamp. The shape of the weld corresponds to the perimeter edge seal 8 as described in the ostomy pouches 1, 201 of FIGS. 1 to 3 and 4-6.

(78) As can be seen from FIG. 8 (a photograph of sheet 313/314 in the region of the perimeter edge seal, 315, 8, 208) the region which has been welded is virtually indistinguishable from the remainder of the sheet of woven material 313, 314. This can be compared visually with the image in FIG. 9, where the welded periphery (P) is clearly distinguishable, because of its mottled edge, with unsightly dark spots (S) (not all of which are labelled).

(79) Referring back to FIG. 7, in this embodiment, the cutting machine 306 is arranged to cut sections of the advancing sheet of material in the shape defined by the perimeter of the ostomy pouch.

(80) In this embodiment, first, the first 311 and second 312 sheets of material are brought together by rollers (not shown) such that they are in contact and advance at the same rate as one another. Next, the third 313 and fourth 314 sheets of comfort material are brought together on opposite sides of the first 311 and second 312 sheets of film material by rollers (not shown). The third sheet 313 is brought adjacent to the first sheet 311 such that the continuous layer of film material 313b faces the first sheet 311. Similarly, the fourth sheet 314 is brought adjacent the second sheet 213 such that the continuous layer of film material 314b faces the second sheet 312. As such, all four sheets are in contact and advance at the same rate. The sheets thus are stacked in the following order: third 313; first 311; second 312; and, fourth 314.

(81) In this embodiment, the advancing sheet of material then enters the stamp welding machine 305. The stamp welding machine 305 applies the heated stamp to the advancing sheet creating a sealed weld line 315 that corresponds to the perimeter of the ostomy pouch 310. The heated stamp can be applied either to the comfort layer which will be at the rear in use, or that which will be at the front, since direct application of heat does not cause the continuous layer of film material to leak through the fabric layer and cause unsightly mottling/spotting. This is to be contrasted with the approach of PCT/GB2021/051340, where despite rigorous testing of various different webs of EVA, one could not be found that did not leak through the fabric, at least on one side.

(82) The continuous layers of film material 313b and 314b, facilitate the fabric layers 313a and 314a welding to the first 311 and second 312 layersthis is especially the case where the continuous layers of film material 313b, 314b are formed from the same material as the first and second layers 311, 312, e.g. when they are all EVA. This process generates a series of sealed ostomy pouches 310 in the advancing sheets. In this embodiment, the stamping machine only welds around the perimeter of the pouches, leaving a cavity within the pouch 310.

(83) In this embodiment, the advancing sheets then enter the cutting machine 306. The cutting machine cuts around the perimeter of the sealed weld line 315 created by the stamping machine 305. This frees each ostomy pouch 310 from the advancing sheets where they can be collected or further prepared. Welding and cutting could of course take place simultaneously.

(84) In other embodiments, additional layers of material may be introduced. In one embodiment, a fifth sheet of comfort layer material is used (not shown) and is applied on the same side of the pouch as the third 313 sheet. This allows the front comfort layer to be comprised of an upper part 6a and lower part 6b or 6bi as described in relation to FIGS. 1 to 3 above, where for example, the third layer forms the lower part and the fifth layer forms the upper part. Advantageously, the third 313 and fifth sheets can be welded to the pouch simultaneously with the other layers, forming the pouch with an overlapping region 115 in a single stamp welding process.

(85) 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.