GB2287193A - Manufacture of ostomy bag having associated filter - Google Patents

Abstract

A method of manufacturing an ostomy bag comprises taking a sheet of filter material comprising a fused network of PTFE particles in accordance with any one of the claims of U.K. Patent Application No. 2 263 908, laminating it either directly or indirectly to a sheet of synthetic plastics material, punching out portions such as discs from the laminate, and attaching that surface of the disc which comprises the synthetic plastics material either directly or indirectly to a sheet of plastics film which is to constitute one wall of an ostomy bag. The laminated plastics sheet may be a non-woven open matrix web of ethylene vinyl acetate or ethylene methyl acrylate or a polyester non-woven matrix. Such sheet may be attached to the bag wall by heat and pressure welding. Alternatively, a woven patch 30 may be placed over the filter material 16/EVA film 28 composite and annularly welded to the bag wall film 10. <IMAGE>

Description

MANUFACTURE OF OSTONY AND LIKE POUCHES OR BAGS, AND BAGS WHEN SO MADE This invention relates to the manufacture of ostomy bags embodying gas deodorising filters. A filter, apparently based on ideas in U.K. Patent Application No. 2,242,431A has been suggested in U.K. Patent Application No. 2 263 908A and PCT Application W093/14722.

However, no practically-useful information is given in the '908 application on how these filters are to be attached to ostomy bags under today's demanding manufacturing conditions. It would be desirable if there were a rapid, effective and reliable way in which this filter could be embodied in an ostomy bag. While the invention may be employed in any ostomy bag, it is particularly advantageous in an ileostomy bag.

According to the present invention, there is provided a method of manufacturing an ostomy bag which comprises taking a sheet of filter material in accordance with any one of the claims of U.K.

Patent Application No. 2 263 908, laminating it either directly or indirectly to a sheet of synthetic plastics material, punching out portions, herein referred to as discs, from the laminate, and attaching that surface of the disc which comprises the synthetic plastics material either directly or indirectly to a sheet of plastics film which is to constitute one wall of an ostomy bag.

It will be understood that whereas the punched out filters will normally be circular, they may instead be oval, rectangular, polygonal or of any other suitable shape. The term "disc" in this specification is used in this specification to comprehend all these possibilities.

According to a first embodiment of the invention, a rectangular sheet of filter material in accordance with any one of the claims of U.K. Patent Application No. 2 263 908 is taken. A non-woven spun bonded open matrix web made of EVA (ethylene vinyl acetate) or EMA (ethylene methyl acrylate) is laminated to the filter material using an intervening adhesive which is applied either in a diamond-roll bonding pattern or as a dot matrix pattern. The filter material sheet and the non-woven sheet are attached together by this adhesive to produce a laminate. Discs are then punched out using a punch having a circular cutting blade. Thereafter, the resulting discs are attached to a sheet of film which is to constitute one wall of the ostomy bag, the non-woven layer being united in face-to-face manner with the bag wall film by a heat and pressure welding operation using an annular tool. By using such a tool, the filter is firmly fixed to the bag wall film over an annular area which surrounds a hole or slit in the bag wall. The slit may be an S-shaped slit.

According to a second embodiment of the invention, a sheet of filter material as referred to above is laminated to a synthetic plastics film which has been pre-punched or pre-perforated to have a plurality of holes extending therethrough. This plastics film is laminated to the filter material layer, using heat and pressure and any suitable adhesive, and, after it has been left to cool, is punched out into filter discs. The surface of these discs that carries the film, which may for example be EVA or EMA, is attached by a suitable adhesive or by heat and pressure welding to the plastics wall of an ostomy bag.

According to a third embodiment of the invention, a sheet of EVA film is subjected to repeated punch-out operations so producing a plurality of annular "washers" of EVA. These are then loaded into the magazine of an automatic heat welding machine, and are sequentially attached, by this machine, one by one to a series of filter discs of similar outside diameter which are sequentially fed in synchronism to the work table of the machine. After the composite filter discs so produced have been allowed to cool, they are sequentially attached to respective ostomy bags by heat welding the EVA side of the composite disc onto the ostomy bag wall film.

According to a fourth embodiment of the invention, a sheet of filter material as referred to above is taken and a plurality of discrete filter discs are punched out of it. These discs are then loaded into the magazine of a hot melt adhesive applicator machine.

In this machine hot melt EVA adhesive is applied in a pattern of discrete dimples, onto one surface of each of a series of filter discs, in a sequential manner so that the dimples are scattered over an annular ring on that surface. The resulting filter discs bearing the adhesive are then attached in sequence to successive ostomy bag wall films by a heat welding operation which causes the EVA adhesive dimples to be brought into contact with the bag wall film.

According to a fifth embodiment of the invention, annular rings of a hot melt adhesive such as EVA are formed by an injection moulding process. These rings are pre-attached to filter discs cut from a filter sheet in accordance with the above-mentioned patent application No. 2,263,908A, the attachment involving using a radiant heating or an induction heating technique. The composite discs are allowed to cool and are then presented to and attached to the ostomy bag using a heat welding operation using an annular heat welding tool, in a similar way, as regards this operation, as described in the first embodiment referred to above.

According to a sixth embodiment of the invention, a sheet of filter material in accordance with the above mentioned patent application is taken and to it is laminated a polyester non-woven matrix. The lamination is achieved using M-web polyurethane adhesive between the filter sheet and the polyester matrix. Sintered hot melt adhesive powder is then taken and transfer coated onto the polyester non-woven web, which then constitutes a composite web. Composite filter discs, which may be circular, are then punched out of the composite web, and can be heat welded onto the ostomy pouch wall by placing the EVA-covered surface of the composite disc into contact with the pouch wall and then carrying out a heat and pressure welding operation using an annular tool.

The invention will be better understood from the following description of particular embodiments thereof, given with reference to the following Examples and accompanying drawings, in which like reference numerals represent like parts and in which: Figure 1 is a front view of one embodiment of ostomy bag incorporating a filter and made in accordance with an embodiment of the method of the invention; Figure 2 is a diagrammatic side view of the bag shown in Figure 1; and Figure 3 illustrates components which may be employed in one embodiment of the invention.

Example 1 A rectangular sheet of material in accordance with any one of the claims of U.K. Patent Application No. 2 263 908 is taken. This sheet may for example measure approximately 30 cms. by 60 cms. A nonwoven spun-bonded open matrix web made of EVA/EMA is laminated to the filter material using an intervening adhesive which is applied either in a diamond roll bond pattern or as a dot matrix. The filter sheet and the non-woven sheet are attached together by a suitable adhesive to produce a two-layer laminate. The discs are then punched out using a punch having a circular cutting blade of approximately one inch diameter. Thereafter, the resulting discs are attached to a sheet of film which is to constitute one wall of the ostomy bag. In this attachment step, the non-woven layer is united in face-to-face manner to the bag wall film by a heat welding operation using an annular tool. By using such a tool, the filter is firmly fixed to the bag wall film over an annular area which surrounds a hole or slit in the bag wall. The slit may be an S-shaped slit.

Example 2 A sheet of filter material as referred to above is laminated to a synthetic plastics film which has been pre-punched or pre-perforated to have a plurality of holes extending therethrough. The preferred hole size is approximately 300 microns diameter, and the hole distribution is preferably about 40 holes per square inch. The material thickness is 100 to 150 microns. This film is laminated to the filter material layer, using heat and pressure and any suitable adhesive, and, after it has been left to cool, the laminate is punched out into filter discs. The surface of these discs that carries the film (which may for example be EVA) is attached over an annular region surrounding a gas exit hole or slit by a suitable adhesive or by heat and pressure to the ostomy bag wall film. This attachment may be made as described in Example 1 above.

Example 3 A sheet of EVA film of thickness approximately 100 to 150 microns is subjected to repeated punch-out operations so producing a plurality of separate annular "washers". These are allowed to cool.

They are then loaded into the magazine of an automatic heat welding machine, and are sequentially attached, by this machine, one by one to a series of filter discs of similar outside diameter which are sequentially fed in synchronism to the work table of the machine.

After the composite filter discs so produced have been allowed to cool, they are sequentially united to respective ostomy pouches by heat welding the EVA side of the composite disc onto the pouch wall film.

Example 4 A sheet of filter material as referred to above is taken and a plurality of discrete filter discs are punched out of it. These discs are then loaded into the magazine of a hot melt adhesive applicator machine. In this machine, hot melt EVA adhesive is applied as discrete dimples, or discrete dots, in sequential manner, onto one surface of each filter disc over an annular portion of said surface.

The resulting filter discs each bearing the adhesive ring but with the central portion free of adhesive are then attached in sequence to successive ostomy bag wall films by heat welding which is carried out so that the EVA adhesive dimples or dots are brought into contact with the bag wall film.

Example 5 A annular rings of a hot melt adhesive such as EVA are formed by an injection moulding process. These rings are pre-attached to filter discs cut from a filter sheet in accordance with the above-mentioned patent application, using a radiant heating or an induction heating technique. The composite discs are allowed to cool and the EVA-coated sides of them are then presented to and attached to the ostomy bag by a conventional heat welding operation using a standard annular heat welding tool.

Example 6 A sheet of filter material in accordance with the above mentioned U.K. Patent Application No. 2,263,908 is taken and to it is laminated a polyester non-woven matrix. The lamination is achieved using M-web polyurethane adhesive as the intervening adhesive between the filter sheet and the polyester matrix. Sintered hot melt adhesive powder is then taken and transfer coated onto the polyester non-woven web, so forming a composite web. Composite filter discs, which may be circular, are then punched out of the composite web, and can be heat welded onto the pouch wall by placing the EVA-covered surface of the composite disc into contact with the wall and then applying a heat and pressure welding operation using an annular tool, in a similar way, as regards operation, as described in Example 1.

It will be seen that there have been provided a number of rapid, effective and reliable methods for attaching a filter in accordance with U.K. Patent Application No. 2 263 908A to the wall of an ostomy bag. As will be appreciated, the invention also extends to ostomy bags produced by the respective methods defined herein.

Referring now to Figures 1 and 2, one embodiment of open-bottom ostomy bag is illustrated. This comprises a front wall 10 and a rear wall 12. The rear wall 12 carries a coupling 14, e.g. a coupling in accordance with British Patent No. 1 571 657, by which the bag can be attached to a medical grade adhesive pad (not shown) worn by the wearer. A filter 16 is attached to the front wall 10 of the bag, using a method as outlined in any one of Examples 1-6 herein. The bag walls are welded together by a peripheral weld seam 18. On the rear side of the bag only, a comfort backing sheet 20 is provided, also attached to the bag in the same operation which welds the peripheral seam 18. This comfort material is preferably needled polyethylene.

It may embody about 5% vinyl acetate and may have approximately 15% open area. The filter 16 is covered by an external patch of gaspermeable material 22, which is secured around its edge to the adjacent bag wall film. The bag has an outlet 24 which can be closed by a suitable clip or fastener. One example of a suitable clip is seen in U.K. Patent No. 2,188,085.

The constructional details of one embodiment of the filter can be seen from Figure 3.

Figure 3 shows one possible relatively high permeability arrangement in which a filter disc 16 is mounted on a plastics film 10 which constitutes a front wall of the bag. A hole 26 of diameter 12.7mm (+ inch) is made in the film 10. A patch of EVA film 28 is welded (as specified in Example 3 herein) to the disc 16. This has a central hole 28A of diameter and a cover patch 30 of film such as M374 film is provided with a central hole 30A of diameter 6mm and is welded by an annular weld over the area indicated 32 so fixing the cover patch 30 to the film 10. This cover patch 30 may be of about 38mm diamter, and the hole 26 of about 10mm diameter. In an alternative arrangement, which may be employed when a heavier carbon loading is present in the film disc 16, the hole 26 may be of diameter 4mm and the hole 28A may be of diamter about 6mm. The width of the annular weld 32 may be about 3mm.

Claims (9)

1. A method of manufacturing an ostomy bag which comprises taking a sheet of filter material in accordance with any one of the claims of U.K. Patent Application No. 2 263 908, laminating it either directly or indirectly to a sheet of synthetic plastics material, punching out portions, herein referred to as discs, from the laminate, and attaching that surface of the disc which comprises the synthetic plastics material either directly or indirectly to a sheet of plastics film which is to constitute one wall of an ostomy bag.

2. A method according to claim 1 in which a non-woven spun bonded open matrix web made of EVA (ethylene vinyl acetate) or EMA (ethylene methyl acrylate) is laminated to the filter material using an intervening adhesive which is applied either in a diamond-roll bonding pattern or as a dot matrix pattern; in which the filter material sheet and the non-woven sheet are attached together by this adhesive to produce a laminate, discs being punched out using a punch having a circular cutting blade; and in which the resulting discs are attached to a sheet of film which is to constitute one wall of the ostomy bag, the non-woven layer being united in face-to-face manner with the bag wall film by a heat and pressure welding operation using an annular tool.

3. A method according to claim 1 in which the sheet of filter material is laminated to a synthetic plastics film which has been prepunched or pre-perforated to have a plurality of holes extending therethrough, and in which the plastics film is then laminated to the filter material layer, using heat and pressure and any suitable adhesive, and, after it has been left to cool, is punched out into filter discs, thereafter the surface of these discs that carries the film is attached by a suitable adhesive or by heat and pressure welding to the plastics wall of an ostomy bag.

4. A method according to claim 1 in which a sheet of EVA film is subjected to repeated punch-out operations so producing a plurality of annular "washers" of EVA, and these are then loaded into the magazine of an automatic heat welding machine, and are sequentially attached, by this machine, one by one to a series of filter discs of similar outside diameter which are sequentially fed in synchronism to the work table of the machine; the composite filter discs so produced are then allowed to cool, and are sequentially attached to respective ostomy bags by heat welding the EVA side of the composite disc onto the ostomy bag wall film.

5. A method according to claim 1 in which a sheet of the said filter material is taken and a plurality of discrete filter discs are punched out of it and are loaded into the magazine of a hot melt adhesive applicator machine; in said machine hot melt EVA adhesive is applied in a pattern of discrete dimples, onto one surface of each of a series of filter discs, in a sequential manner so that the dimples are scattered over an annular ring on that surface; thereafter, the resulting filter discs bearing the adhesive are attached in sequence to successive ostomy bag wall films by a heat welding operation which causes the EVA adhesive dimples to be brought into contact with the bag wall film.

6. A method according to claim 1 in which (a) annular rings of a hot melt adhesive such as EVA are formed by an injection moulding process, (b) these rings are pre-attached to filter discs cut from said sheet of filter material the attachment involving radiant heating or induction heating, (c) the composite discs are allowed to cool, and (d) are presented to and attached to the ostomy bag using a heat welding operation using an annular heat welding tool.

7. A method according to claim 1 in which said sheet of filter material is laminated to a polyester non-woven matrix, using M-web polyurethane adhesive between the filter sheet and the polyester matrix; sintered hot melt adhesive powder is then taken and transfer coated onto the polyester non-woven web, which then constitutes a composite web; composite filter discs are then punched out of the composite web, and can be heat welded onto the ostomy pouch wall by placing the EVA-covered surface of the composite disc into contact with the pouch wall and then carrying out a heat and pressure welding operation using an annular tool.

8. A method of manufacturing an ostomy bag substantially as herein described with reference to and as illustrated in any one of Examples 1-6 herein.

9. Any novel combination of method steps and/or manufacturing operations disclosed herein.