External male urinary catheter and method and apparatus for manufacturing such a catheter

The neck portion (3) of an external male urinary catheter has increased wall thickness and rigidity and comprises a first part (3a) having a maximum diameter corresponding to that of the catheter body portion (1) and a second part (3b) joining a drainage tube. Between the first and second parts of the neck portion (3) a constriction (5) is formed having axial and radial dimensions to receive and retain the catheter body portion in a rolled-up condition. The second part (3b) of neck portion provides a bulbous surge chamber to prevent kinking of the drainage tube and back-flow of urine.

This invention relates to an external male urinary catheter comprising a 
soft thin-walled substantially cylindrical body portion, which is open at 
one end and merges at the other end into a neck portion of increased wall 
thickness and rigidity compared to the body portion said neck portion 
comprising a first part having a maximum diameter corresponding to that of 
the body portion and a second part joining a narrow drainage tube to be 
connected to a urine collection bag. 
Catheters of this kind are designed to be arranged as a condom on a penis 
in order to act as an aid against male urinary incontinence in a safe 
manner free of leakage and with the fewest possible inconveniences to the 
users, who may be fysically handicapped or elderly persons for whom 
greater openness concerning problems of incontinence has led to a growing 
demand for such aids. Whereas in the past special adhesive linings was 
often used to securely fasten the catheter to the normal flaccid penis, as 
known e.g. from U.S. Pat. No. 4,187,851 and GBA-2 096 901 it has become 
increasingly common to provide the catheter body portion with an 
integrated layer of a pressure-sensetive adhesive, which is either 
initally applied to the innerside of the body portion, as known from 
WO86/00816 or transferred to the inner side during unrolling of the 
rolled-up body portion of the catheter as known from GB-B-2 106 784. To 
prevent sticking together of successive windings of the rolled-up body 
portion the outer side thereof is protected by an adhesive release layer 
opposite the adhesive layer. 
To facilitate application of the catheter the device is usually supplied, 
as mentioned above, with the catheter body portion rolled up from the open 
end towards the neck portion. 
In prior art devices it has not been possible, however, to secure that the 
rolled-up catheter body part is always located at one particular position 
on the catheter just inside the neck portion and unavoidable variations in 
the location of the rolled-up portion will frequently lead the 
inconvenience during application that the user or a nurse assisting him 
must grip with the fingers on a part of the very thin-walled body portion 
and place it on the sensitive surface of the penis glans. 
In order to avoid this inconvenience it has been suggested to use various 
forms of catheter applicators as known e.g. from U.S. Pat. No. 4,540,409 
and EP-A-0236.458 Such accessories will, however, unavoidably increase the 
costs of the catheter-applicator combination to a level counteracting the 
intended supply of such devices as disposable articles. 
In order to remedy these deficiencies of prior art products the present 
invention provides a catheter of the kind mentioned, which is 
characterized in that a constriction is formed between said first and 
second parts of the neck portion said constriction having axial and radial 
dimensions to receive and retain the catheter body portion in a rolled-up 
condition, the second part of the neck portion between the constriction 
and the drainage tube tapering towards the drainage tube from a maximum 
diameter exceeding the minimum diameter of the constriction to provide a 
bulbous surge chamber to prevent kinking of the drainage tube and 
back-flow of urine. 
Thereby, the catheter may always be supplied to the user with the rolled-up 
body portion located at ecactly the same position on the neck portion of 
the catheter having increased wall-thicknes and regidity and so close to 
the drainage tube that on application the user or nurse may simply grip 
the drainage tube which is outside the penis itself and hold the neck 
portion against the penis glas, whereafter the body portion may be 
unrolled without any need to use a special applicator. 
Additionally, the constriction provided in the neck portion allow the part 
of the neck portion outside the constriction to function as a bulbous 
surge chamber and prevent kinking of the drainage tube and back flow of 
urine even if the constriction separating this chamber from the catheter 
body portion has a greater diameter than normally used in prior devices 
provided with such anti-kink mechanisms and know e.g. from the 
above-mentioned GB-B 2 106 787 and U.S. Pat No. 4,540,409. 
The invention further relates to a method for manufacturing an external 
catheter as defined and comprising the steps of dipping a substantially 
cylindrical mandrel having an outer contour corresponding to the envisaged 
inner contour of the catheter including the drainage tube into a liquid 
state rubber-based material and allowing the mandrel carrying a layer of 
said material to cure, said method being characterized by the use of a 
mandrel having a first part corresponding to the catheter body portion, a 
second part corresponding to the drainage tube and an intermediate part 
corresponding to the neck portion and having a circumferential groove and 
by repeated dipping and curing of said second part and said intermediate 
part only after an initial dipping and curing operation involving all 
parts of the mandrel to provide increased thickness and rigidity to said 
second part and said intermediate part. 
Additionally, the invention relates to an apparatus for carrying out the 
method and comprising a mandrel including a first cylindrical mandrel part 
of a diameter corresponding to the inner diameter of a catheter body 
portion and a second cylindrical mandrel part of a substantial reduced 
diameter corresponding to the catheter drainage tube, said apparatus being 
characterized by having between said first and second mandrel parts an 
intermediate part in which a circumferential groove is formed, said groove 
having axial and radial dimensions to provide the constriction in the 
catheter neck portion between the body portion and the drainage tube said 
groove being provided between a first part of said intermediate portion 
having a maximum diameter corresponding to that of the first mandrel part 
and a second part tapering towards said second mandrel part from a maximum 
diameter exceeding the minimum diameter of the groove.

In the embodiment shown in FIGS. 1 and 2 the external male urinary catheter 
according to the invention comprises a very soft, thin walled and highly 
flexible body portion 1 with an open end 2. At the opposite end the body 
portion 1 merges into a neck portion 3 having increased wall-thicknes and 
rigidity compared to the body portion 1. 
The neck portion 3 comprises a first part 3a of a maximum inner diameter 
D.sub.3 corresponding to the inner diameter of the body portion 1 and a 
second part 3b joining a narrow drainage tube 4 formed for connection to a 
urine collection bag, not shown, which is normally fastened to one leg of 
the user. 
According to the invention a constriction 5 is formed between the first and 
second parts 3a and 3b of the neck portion 3, said constriction having 
acial and radial dimensions to receive and retain the body portion 1 in 
the rolled-up supply condition shown in FIG. 1. The second part 3b of the 
neck portion 3 between the constriction 5 and the drainage tube 4 tapers 
towards the drainage tube 4 from a maximum diameter D.sub.1 exceeding the 
bottom diameter D.sub.2 of the constriction 5 to provide a bulbous surge 
chamber 6 serving to prevent kinking of the drainage tube 4 and back-flow 
of urine, when the catheter is in use. 
Whereas the diameter D.sub.3 of the catheter body portion 1 and the first 
part 3a of the neck portion 3 may vary for adaption to different sizes of 
the male penis, e.g. from about 20 to about 40 mms the axial and radial 
dimensions of the constriction 5 serving to accomodate the rolled-up body 
portion will remain substantially the same regardless of the diameter of 
the body portion. 
In preferred embodiments the minimum or bottom diameters D.sub.2 of the 
constriction will thus be 4.5 to 6.5 mms less than the body portion 
diameter D.sub.3 and the surface contour of the constriction 5 between the 
diameter D.sub.2 and the diameter D.sub.3 of the first part 3a of the neck 
portion 3 will be substantially conical with a half apex angle v of 
45.degree. to 50.degree. with the axis of the catheter, whereas the 
maximum diameter D.sub.1 of the second part 3b of the neck portion 3 will 
be 2.4 to 3.0 mms less than the diameter D.sub.3 of the first portion 3a. 
By these dimensions the rolled-up body portion 1 will be very safely 
located in the constriction 5 and on application of the catheter it will 
be sufficient for the user or a nurse assisting him to grip the drainage 
tube 4 and place the catheter in the rolled-up condition with the neck 
portion 3 against the penis glas and unrole the body portion 1. In 
particular the above-mentioned range for the angle of the conical surface 
contour of the constriction 5 implies that a certain slight resistance 
will have to be overcome before the rolled-up portion may leave the 
constriction 5 and reach the cylindrical body portion inside the neck 
portion 3. 
As shown in FIG. 2 the body portion 1 may in a manner known per se from 
WO86/00816 be provided on part of its inner side with an integrated layer 
of a pressure-sensitive adhesive and on its outer side with a 
corresponding adhesive release layer 8 to prevent successive windings of 
the rolled-up body portion from sticking inseparably together. 
For manufacturing the catheter a mandrel form 9 as shown in FIGS. 3 and 4 
may be used. The mandrel 9 has an outer contour corresponding to the 
envisaged inner contour of the catheter including the drainage tube and it 
comprises a first cylindrical portion 10 of a diameter D.sub.3 
corresponding to the catheter body portion 1, a second cylindrical portion 
11 of a substantially reduced diameter corresponding to the drainage tube 
4 and an intermediate portion 12 in which the circumferential groove 13 is 
formed to provide the constriction 5 in the catheter neck portion 3. Thus 
the groove 13 is provided between a first part 12a of the intermediate 
portion 12 having the diameter D.sub.3 and a second part 12b tapering 
towards the second mandrel portion 11 from a maximum diameter D.sub.2 
exceeding the minimum or bottom diameter D.sub.2 of the groove 13. 
In a preferred embodiment the axial and radial dimensions of the groove 13 
on the mandrel 9 will correspond to the dimensions mentioned above for the 
constriction 5. 
In a first manufacturing stage the mandrel 9 is dipped into a bath of a 
liquid-state rubber-material like latex as illustrated in FIG. 3 to a 
level 14 corresponding to the desired location of the open end 2 of the 
catheter to receive a layer of the liquid material to provide the soft 
thin-walled and flexible body portion 1. 
After removal of the mandrel 9 carrying such a layer from the bath the 
rubber-based latex material is allowed to cure. 
To obtain the increased wall thicknes and regidity of the catheter drainage 
tube 4 and the neck portion 3 with the constriction 5 a new dipping 
operation is carried out, but this time only the second part 11 and the 
intermediate part 12 of the mandrel 9 is lowered into the bath to the 
level 15. 
Depending on the number of succssive dipping and curing operations the 
thickness of the drainage tube 4 and the neck portion 3 may be adjusted to 
satisfied prescribed specifications. 
After completion of all dipping and curing operations the catheter may now 
be provided with the integrated inner and outer layers 7 and 8 of a 
pressure-sensitive adhesive and an adhesive release agent such as 
silicone, respectively, by being arranged on another mandrel 16, which as 
shown in FIG. 5 may be supported for rotational movement in the direction 
of the arrow 17. 
On a part of its axial length corresponding to the desirable location of 
the adhesive layer 7 the mandrel 16 has a circumferential depression 18 in 
which an insert 19 of an adhesive rejecting silicone based material is 
arranged. 
Prior to arrangement of the pre-fabricated catheter 20 on the mandrel 16 
adhesive is applied to the outer surface of the insert 19 in a liquid 
state, e.g. from a spraying device 21 during rotation of the mandrel 16 in 
the direction of the arrow 17. 
Subsequently the catheter 20 is arranged for which purpose the mandrel 16 
may be formed with internal ducts for supplying pressurized air to permit 
easy arrangement of the catheter 20 as known e.g. from WO86/00816. 
With the catheter 20 subsequently arranged on the mandrel 16 the adhesive 
release layer 8 is applied to the outer side of the catheter to extend 
somewhat outside the upper and lower boundaries of the adhesive layer 7 on 
the inner side. The release agent may like the adhesive be supplied in a 
liquid stage e.g. by means of the spraying device 22 under simultaneous 
rotation of the mandrel 16 in the direction of the arrow 17. 
Finally the catheter body portion is rolled up from the open end, whereby 
the adhesive layer initially applied to the insert 19 on the mandrel 16 
will slip the insert 19 and stick to the inner side of the catheter, which 
is rolled-up until the rolled-up portion reaches the constriction 5 in the 
catheter neck portion. 
Whereas the mandrel 16 has first and intermediate portions corresponding to 
the portions 10 and 12 of the mandrel 9 in FIGS. 3 and 4 it does not need 
having a second portion corresponding to the portion 11 of the mandrel 9. 
Whereas in FIGS. 3-5 only a single mandrel is shown it will be understood 
that in practice a considerable number of mandrels may be supported by a 
common supporting member and operated simultaneously in the various 
manufacturing stages described above. 
The constriction or external groove or channel 5 provided by the reduced 
diameter portion intermediate the axial length of the neck portion 
receives and locates the cylindrical body portion 1 in the rolled up 
condition and leaves a surge chamber 6 between the reduced diameter 
portion and the inlet to the drainage tube 4. The additional thickness of 
the neck portion 3 lends support for the body portion in the rolled up 
condition and together with the surge chamber 6 helps to prevent kinking 
of the drainage tube and the back-flow of urine.