Abstract
An ostomy bag includes a textile layer bonded to the barrier film along a portion of an outer periphery of the ostomy bag.
Claims
1. An ostomy bag comprising: a barrier film; and a textile layer bonded to the barrier film along a portion of an outer periphery of the ostomy bag; wherein the textile layer comprises a number of threads, with each of the threads comprising a plurality of fiber filaments; wherein the textile layer is one of a woven textile and a knitted textile that is sealed to the barrier film in an attachment zone formed along the portion of the outer periphery of the ostomy bag such that less than an entirety of the fiber filaments of the textile layer in the attachment zone is embedded in the barrier film; wherein the fiber filaments of the textile layer have a higher melting point than the barrier film; wherein the textile layer has an increased wear strength compared to a nonwoven layer as measured by resistance to pilling evaluated according to test standard DS/EN ISO 12945-2:2000; wherein a peel strength between the textile layer and the barrier film is above 5 N per 12.5 mm width in the attachment zone; wherein the textile layer provides the ostomy bag with a resistance against failure caused by tear forces in the attachment zone, where the resistance against failure is at least a factor of 2 greater than a resistance against failure caused by tear forces for a nonwoven layer.
2. The ostomy bag of claim 1, wherein the textile layer bonded to the barrier film provides a comfort layer for the ostomy bag, and fiber filaments in the attachment zone that are not embedded in the barrier film provide a first portion of an external surface of the comfort layer having tactile characteristics identical to tactile characteristics in a second portion of the external surface of the comfort layer, the second portion located outside the attachment zone.
3. The ostomy bag of claim 1, wherein a basis weight of the textile layer is in a range from 40-100 g/m2.
4. The ostomy bag of claim 1, wherein a thread density for the threads of the textile layer is in a range from 30-50 threads/cm.
5. The ostomy bag of claim 1, wherein a number of filaments per thread in the plurality of fiber filaments is in a range from 30-150 filaments/thread.
Description
BRIEF DESCRIPTION OF THE DRAWING
(1) FIG. 1 is a schematic view of the outline of a drainable collecting bag of the type having a foldable outlet and indicating an area of the bag often exposed to failure, e.g. notches, caused by external forces;
(2) FIGS. 2a and 2b schematically illustrate the process of heat welding a comfort layer based on a non-woven material to a barrier film material as in the prior art;
(3) FIGS. 3a and 3b schematically illustrate the process of heat welding a comfort layer based on a textile material to a barrier film material according to the invention, and
(4) FIG. 4 is a print-out photo from a Scanning Electron Microscope showing, in cross-section, a 250-times magnification of a laminated textile comfort layer and barrier film in the welding zone of a sample collecting bag according to the invention.
(5) It is noted that the figures, and particularly the individual elements of the figures, are not necessarily to scale, neither individually nor in relation to each other, but are basically intended to illustrate principles of the invention.
DETAILED DESCRIPTION OF THE DRAWING
(6) FIG. 1 shows the outline of a drainable collecting bag 1 of the type having a foldable outlet and indicating an area 5 of the bag often exposed to failure caused by external forces. The area 5 is particularly exposed to such forces, most often excessive tearing, due to a number of factors, such as the fact that a user typically has to unfold the outlet several times every day to empty collected waste into a toilet bowl, and subsequently clean the outlet and fold it back into its closed or folded position. Moreover, the foldable outlet's position as an extremity of the collecting bag inevitably increases the risk that the outlet may be unintentionally pulled or get entangled with e.g. the clothes of a user, when the outlet is its unfolded position. By providing a textile comfort layer according to the present invention the risk of failure caused by such external forces is significantly reduced or eliminated.
(7) FIG. 2a shows a schematic illustration of the relevant materials of a collecting bag according to the prior art in the production step prior to the welding process. Two separate layers of barrier film material 20a and 20b are provided next to each other and a single layer of a non-woven based comfort layer material 10 is provided on top of the layer 20a.
(8) FIG. 2b schematically shows the same materials as in FIG. 2a after the welding process step. The materials 10, 20a, 20b have been bonded together by the heat applied by the welding process. The heat may be applied from one single side of the laminate construction, e.g. from the side of the comfort layer 10, or from both sides of the laminate, e.g. both from the side of the comfort layer 10 and from the side of the barrier film layer 20b. The figure illustrates how all three layers have been bonded together by melting the material of the layers into a coherent mass, the dotted line 11 representing that the engaging surfaces of the layers are no longer individually distinct. The heat provided by the welding process has melted the barrier film material 20a and 20b, but has also melted the (random) fibre structure of the non-woven material 10 whereby the welding zone hardens when it cools off and thus has no or only very little resistance towards external forces left, and is particularly prone to the creation of notches.
(9) FIG. 3a is similar to FIG. 2a, only here the material of the comfort layer is no longer non-woven based, but instead a textile comfort layer according to the invention. The textile is schematically represented by three circles 15 intended to illustrate individual threads of the textile comfort layer. In practice, of course, each individual thread comprises a higher number of fibre filaments (not shown) per thread but for the sake of simplicity, the principle of the invention is shown only by way of threads and in the figure limited to three threads. Any interlaced threads of the cross-direction of the textile are also not shown in the figure.
(10) FIG. 3b is similar to FIG. 2b, but schematically illustrates how the threads 15, each comprising a number of individual fibre filaments of the textile comfort layer, are at least partly physically anchored (illustrated by example at position 16) in the melted barrier film material 20a and 20b, as the melted barrier film material flows into the structure of the threads in the textile comfort layer material without melting the fibre structure of the threads. The threads 15 of the textile material are not melted, as the textile material has a higher melting point than that of the barrier film. In reality, the melted barrier film material will flow in between the individual fibre filaments of each thread. Thus, the resulting surface of attachment between the fibre filaments and the barrier film material is significant and thereby the textile comfort layer 15 and the barrier film materials 20a, 20b are laminated to each other such that the peel strength between the barrier film material and the comfort layer is on par with that between a barrier film material and a non-woven based comfort layer, while achieving an improved resistance against external forces, such as tear forces resulting in the creation of notches.
(11) FIG. 4 is a print-out photo of a 250-times magnification of the laminated textile comfort layer and barrier film in the welding zone of a sample collecting bag according to the invention. The photo shows how the schematically illustrated (FIG. 3b) principles of the invention are implemented in practice. The figure shows how some of the individual fibre filaments 17 of the threads 15 (FIG. 3b) of the textile comfort layer have been physically anchored in the melted barrier film mass 20, and also shows that not all of the fibre filaments 18 are embedded. The number of individual threads, and thus also the number of fibre filaments, is much higher than in the schematic FIG. 3a. Also, fibre filaments 19 of the interlaced threads of the cross-direction can be observed. Some fibre filaments 17 are completely embedded in the melted material 20, whereas others are only partly 21 or not at all 18 embedded in the melted material. Thus, the melted barrier film material has flowed into the space or spaces between the individual fibre filaments of the threads and the resulting surface of attachment between the fibre filaments and the barrier film material becomes significant. Thereby, the textile comfort layer 15 and the barrier film material 20a, 20b are laminated to each other such that the peel strength between the barrier film material and the comfort layer is surprisingly high.
(12) Furthermore, still referring to FIG. 4, the fact that some filaments 18 are free from contact with the melted material 20 provides another advantage of the present invention in that a much less visible and indeed softer welding zone or area is achieved compared to collecting bags with non-woven comfort layers. In fact, the provision of the free (not melt-embedded) filaments of the textile comfort layer in practice means that, to the naked eye at least, there is no visible difference between the surface characteristics of the comfort layer in the welding zone and anywhere else on the surface of the comfort layer. The tactile feel and/or characteristics of the attachment or welding zone of a collecting bag according to the invention is also softer and less rigid than in the case of a non-woven comfort layer and is the same, or at least experienced the same by an individual, as anywhere else on the surface of the comfort layer.
(13) The layers outside the surfaces of the textile comfort layer in FIG. 4, e.g. dark layer 30, are parts of a tool holding the sample in place during the test. It should be noted that for the test preparation, the sample of FIG. 4 was put into liquid nitrogen before cutting the cross-section out of sample, as cutting the sample at room temperature causes the textile and the barrier film material to be “mashed” into each other.
Experimental Part
(14) Peel Strength Between Comfort Layer and Barrier Film
(15) The peel strength between a comfort layer and the barrier film material of a collecting bag was measured to show that for a textile based comfort layer according to the invention said peel strength is on par with that of a collecting bag having a traditional non-woven comfort layer attached to the barrier film.
(16) Test samples included test specimens having a non-woven comfort layer attached to a SaranEX 630G barrier film material from Dow Europe and test specimens having a textile material comfort layer (approx. parameters: weight 71 g/m.sup.2, yarn number 100 dtex (warp) and 94 dtex (weft) & thread density 40 threads/cm (warp) and 32 threads/cm (weft)) attached to a Nexcel MF513 barrier film material from SealedAir.
(17) The peel strength test may be carried out either on a texture analyser, e.g. model L500X-8945 from Lloyd or model 5543 from Instron using a 50N load cell and under normal room conditions. Table 1 below shows results obtained with the texture analyser model from Instron. The tensile strength speed (or peel speed) was set to 200 mm/min.
(18) Test procedure includes cutting a sample of the bag (test specimen) perpendicular to the attachment zone or welding 12.5 mm wide on a length of 10 cm. The holding fixtures (or jaws) holding the sample are fixed to the texture analyser, and the sample is set parallel to the pull direction. Further directions to the test can be found below for the notch sensitivity example.
(19) Table 1 shows average measured values in [N/12.5 mm width].
(20) TABLE-US-00001 TABLE 1 Comfort layer/ Barrier film Non-woven Textile SaranEX 630G 8.189 Nexcel MF513 7.898
(21) Accordingly, the peel strength using a textile based comfort layer according to the invention is found to be on par with the peel strength, when using a non-woven comfort layer.
(22) Notch Sensitivity—External Forces Resistance
(23) In order to show that a collecting bag for human body wastes having a comfort layer based on a textile material has an increased security against failure caused by external forces, a number of test samples were submitted to a tensile strength test, i.e. a test where the samples were torn. The tensile stress at maximum load was measured.
(24) Test samples included 10 test specimens having a non-woven comfort layer (polypropylene spun bond, 30 g/m.sup.2) and 10 test specimens having a textile comfort layer according to the invention. In each group of 10 test specimens, 5 specimens were laminated on to a SaranEX 630G barrier film material from Dow Europe and 5 specimens were laminated on to a Nexcel MF513 barrier film material from SealedAir. All test specimens included a single layer of the barrier film material and a single layer of textile material only.
(25) The tensile stress test was carried out on a texture analyser model 5543 from Instron using a 50N load cell, in an air-conditioned laboratory at a constant temperature of 23° C. and at constant 50% RH.
(26) The test specimens were submitted to the tensile stress test by applying the tearing force in a position corresponding to failure area 5 on the collecting bag outlined in FIG. 1. Each test specimen was mounted in the texture analyser in such a way that the part of the sample adjacent to the left of the tearing force application position was received in a first holding jaw of the texture analyser, and the part adjacent to the right of said position was received in a second holding jaw of the texture analyser. The first holding jaw was connected to an actuator capable of providing a force in a lateral upward direction, whereas the second holding jaw was connected to another actuator providing a force in a lateral downward direction. Load cells were mounted on the holding jaws to measure the applied force at least at the time of failure. Test results are shown in the below tables 2 and 3. Table 2 shows the results of the test for the combination of the non-woven comfort layer mentioned above and the two different barrier film materials from Dow and SealedAir, also described above, respectively. Table 3 shows the results of the test for the combination of a textile material according to the invention and the respective barrier film materials mentioned.
(27) TABLE-US-00002 TABLE 2 Tensile stress at max load No. Specimen [MPa] 1 Non-woven + SealedAir 16.426 2 Non-woven + SealedAir 16.310 3 Non-woven + SealedAir 16.657 4 Non-woven + SealedAir 17.786 5 Non-woven + SealedAir 16.611 6 Non-woven + Dow 10.354 7 Non-woven + Dow 7.791 8 Non-woven + Dow 12.145 9 Non-woven + Dow 11.190 10 Non-woven + Dow 10.493 Mean Non-woven 13.566
(28) TABLE-US-00003 TABLE 3 Tensile stress at max load No. Specimen [MPa] 1 Textile + SealedAir 31.015 2 Textile + SealedAir 30.696 3 Textile + SealedAir 29.172 4 Textile + SealedAir 29.256 5 Textile + SealedAir 34.941 6 Textile + Dow 29.172 7 Textile + Dow 26.320 8 Textile + Dow 25.354 9 Textile + Dow 32.432 10 Textile + Dow 27.635 Mean Textile 29.599
(29) As it can be clearly seen from the results of the performed tensile stress tests, a collecting bag having a textile comfort layer according to the invention has a significantly higher (more than a factor 2) resistance against failure caused by external forces. Particularly, the test results show that a collecting bag with a textile comfort layer is much less prone to failures caused by tear forces and e.g. the risk of creation of notches in the collecting bag is significantly reduced.
(30) In conclusion, it has been shown that a collecting bag having a textile comfort layer according to the present invention has on par peel strength characteristics, but a significantly higher resistance to external forces when compared with traditional non-woven material based comfort layers. Also, the collecting bag of the invention is less dependent on the strength of the barrier film itself to resist external forces due to the use of the textile material.
(31) Furthermore, the present invention provides a collecting bag for human body waste having improved visual and tactile characteristics in the attachment zone(s) between the barrier film material and the comfort layer as supported by the SEM photo of FIG. 4, and further an increased resistance to common wear issues such as snagging and pilling.
