Note: Descriptions are shown in the official language in which they were submitted.
CA 02414395 2002-12-06
WO OI/36290 . ~.-...-f - .. , ,. , ..... . -,..~..~~ a w.afvamvw.v
TEXT,
INJECTION-MOULDED WATER-SOLUBLE CONTAINER
The present invention relates to rigid, water-
soluble containers. It also relates to capsules, in
particular tv capsules that may be utilised for the
delivery into Man' or other animals of substances such as
ingestible ingredients like pharmaceutically- or
nutritionally-active materials, that dissolve or disperse
within the gastro-intestinal tract, and to capsule-like
1o containers, in particular to such containers that may be
utilised for the delivery into an aqueous environment of
substances such as detergents, pesticides, bioeides,
deodorants, dyes and pigments, and water-treatment
chemicals.
Clothes washing compositions may be delivered to a
clothes washing machine by a delivery tray from which the
composition is fed into the washing drum, or they may be
placed directly into the washing drum. The washing
2o compositions may be in powder, liquid or block form.
Liquid compositions have the disadvantage that they may
be spilt. The same applies to powder compositions.
Powder compositions have the additional disadvantage that
they may produce dust which can be inhaled. These
problems are overcome or lessened when blocks of washing
composition are used. These are normally individually
wrapped. On unwrapping a block, for use, it is still
possible that some dust may be produced. Additionally it
is an inconvenience for the consumer to have to unwrap
the block. E'urthermore it is almost impossible for the
user to avoid some contact between the block and his or
her skin, so leading to a requirement for the user tn
CA 02414395 2002-12-06
WO 01/36290 PCT/GB00/0~376
-2-
wash their hands after starting the washing machine. In
fact, all of the methods described involve a risk of .
contact between the composition and the skin, and it is
desirable in all cases for the user to wash their hands
of ter starting the washing machine. In this context it
should be borne in mind that many compositions contain
enzymes to assist the cleaning action. Even though the
user may tolerate enzyme residues which may be left in
clothes after washing, they may still not tolerate
contact between the concentrated washing composition
containing the enzymes, and the skin.
Similar considerations apply in relation to other
areas including fabric care, surface care and
t5 dishwashing. Thus, in relation in particular to
dishwashing compositions, there are also problems of
spillage, dust generation, skin contact and
inconvenience.
2o It is known to package chemical compositions Which
may be of a hazardous or irritant nature in water-soluble
or water-dispersible materials such as films. The
package can simply be added to water in order to dissolve
or disperse the contents of the package into the water.
Fox example, WO 89/12587 discloses a package which
comprises an envelope of a water-soluble or water-
dispersible material which comprises a flexible wall and
a water-soluble or water-dispersible heat seal. The
package may contain an organic liquid comprising, for
example, a pesticide, fungicide, insecticide or
herbicide.
CA 02414395 2002-12-06
WO 01/36290 PCT/CB00/Oi376
-3-
CA-A-1,112,534 discloses a packet made of a water-
soluble material~in film form enclosing within it a
paste -form, automatic dishwasher-compatible detergent
composition. The water-soluble material may be, for
example. polyvinyl alcohol), polyethylene oxide or
methyl cellulose.
It is also known to form water-soluble containers by
l0 thermoforming a water-soluble material. For example, WO
92/17382 discloses a package containing an agrochemical
such as a pesticide comprising a first sheet of non-
planar water-soluble or water-dispersible material and a
second sheet of water-soluble or water-dispersible
t5 material superposed on the first sheet and sealed to it
by a continuous closed water-soluble or water-dispersible
seal along a Continuous region of the superposed sheets.
The above methods of packaging have, however, a
20 number of disadvantages.
The first disadvantage is that they do not have a
particularly attractive appearance. In fields such as
containers used in the domestic environment, an
25 attractive appearance for an article is extremely
desirable. Liquids contained in envelopes of water-
soluble film can have a limp, unattractive appearance.
the second disadvantage is that it is difficult to
30 form two or more separate compartmEnts in the pacltaging
so that two incompatible components are both enclosed but
separated from each other. Although an arrangement has
CA 02414395 2002-12-06
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been described to separate incompatible materials in
Flexible pouches in WO 93/08095, the method proposed is
complex and is not currently achievable in large-scale
manufacturing. It cannot, therefore, be used for
producing large numbers of containers.
The third disadvantage is that there is only limited
control of the release profile of the compositions held
in the containers. For example, when a composition is
held between two planar water-soluble films or in a
thermoformed package, the composition is simply released
at the time when the films dissolve or disperse in water_
While it may be possible to control to a certain extent
the timing of the start of release of the contents, there
~5 can be no control over the rate of release of the
contents since the entire film dissolves or øisperses at
about the same time. ~ Furthermore it can be difficult to
provide an extended time before the contents of the
package are released. An additional problem also arises
with thermoformed packages. If the thermoforming is not
carefully controlled there may be inadvertent thinning of
the film~material at the points where the material is
drawn down into the mould when it is thermoformed. This
could release the contents of the package early.
Additionally, in all of the above packages, it is not
possible to release different compositions at different
times or at different rates since, as discussed above, it
is not possible to incorporate more than one composition
in each water-soluble container.
The fourth disadvantage is that the containers
cannot be produced at a particularly fast rate. When the
CA 02414395 2002-12-06
containers are produced by heat-sealing planar films or
by thermoforming, the containers have to be immediately
filled and sealed. All of these procedures have to be
carried out in succession. This means that it is not
possible to obtain a quick throughput for mass-market
goods such as household products. For example, standard
thermoforming machines can only produce around 400 to 800
containers per minute.
There axe numerous forms of systems used in the
delivery of medical preparations in the market place
today. The two most dominant in relation to oral routes
are capsules made from.hard gelatine, and tablets ' the
so-called solid dose formulations. Hoth of these
presentations have remained virtually unchanged for
decades. Gelatine capsules are made by a dipping
pr-ocess, building up successive layers, while tablets are
formed by compressing a powder or fine granules.
The gelatine capsules currently employed are used
extensively throughout the world to deliver thousands of
prescribed and over-the-counter medications and
nutritional formulations. Unfortunately, they have a
number of highly significant limitations, these
ZS including: their inability easily to be formed into a
shape that facilitates the optimum delivery of their
ingredients into the patient; the fact that gelatine is
animal-based; and the substantial likelihood of them
' sticking in the Patient's oesophagus when they are
swallowed. In recent years these and other limitations -
see below - have been acknowledged, and efforts have been
made to overcome them by finding and using a number of
CA 02414395 2002-12-06
~ wv vii.romv
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materials as alternatives to gelatine, but in most cases
the materials are even more brittle, more difficult to ,
shape, and significantly more expensive than gelatine and
other conventional solid dose delivery systems, and
therefore they have not thus far been used successfully
for this purpose - which leaves the problem of the hard
gelatine capsule, and its disadvantages, still to be
solved. Some of these disadvantages ate as follows:
As noted above, gelatine-is animal-based, being
extracted from bones and hides, and as such it carries
the risk - or, at least, the perceived risk - of being
linked with Creutzfeldt-Jakob disease. The manufacturing
process used to make hard gelatine capsules involv8s a
so-called dipping process, which makes thickness
parameters difficult to control. More significantly, the
process does not lend itself to the more complex shapes,
sizes and chemical characteristics now required within
the pharmaceutical and nutraceutical industries, more
specifically when controlled release is desirable. Hard
gelatine capsules also have an inherent problem of
attracting a static charge, which makes their handling
during manufacture an additional problem, whil8 the
gelatine itself has a tendency to undergo detrimental
23 physical and chemical changes during lung-term storage.
As also pointed out above, gelatine capsules may be
rather hard to swallow properly, for they can all too
easily stick in the oesophagus. Now, this may seem
trivial, but in fact whilst the most frequent cause of
accidents to 8atients in hospitals is falling out of bed,
the second most frequent cause is capsules or tablets
CA 02414395 2002-12-06
V VJ/JVlr7V
sticking in the Patient's oesophagus! Very few Patients
are able to swallow a capsule when lying down, and when a
gelatine capsule sticks in the oesophagus it can be
extraordinarily difficulC to dislodge. Indeed, it has
been shown that drinking liquids such as water fails to
move such a stuck capsule even when taking large amounts,
and on occasion even eating food fails to overcome the
adhesion. Part of the problem may be that a filled
gelatine capsule will float if its contents are not dense
(as is often the case), and will have a tendency to
remain in the mouth, after the initial mouthful of water
has been swallowed. This allows stickiness rapidly to
develop on the surface of the capsule, which in turn
increases the probability that the capsule will stick in
IS the oesophagus when finally swallowed.
It has now been appreciated that the above type of
capsule has utilisati.ons other than in medicine and the
human or animal body. In particular, it has been
realised that many substances that must be packaged for
delivery to their use site could, where that site is an
aqueous environment, be contained in similar, though
somewhat larger, capsules. Thus, a capsule-like
container - a "capsular" container - could be employed to
deliver, for example, detergents to a washing machine,
pesticides to a paddy field, or water-treatment chemicals
.. . to a reservoir. Moreover, by appropriately dimensioning
the various parts of the container, or by suitably
selecting the materials from which they are made,
different parts of the container will in use dissolve at
different times.
CA 02414395 2002-12-06
_ g
The present invention seeks to provide water-soluble
containers which overcome some or all of the above
disadvantages.
The present invention has a number of different
aspects and embodiments as follows:
The present invention provides a rigid, water
soluble container made of an injection moulded polymer,
for example, a polyvinyl alcohol) (pvOH) and/or a
cellulose ether such as hydroxypropylmethylcellulose
(HPMC), which container encases a composition, for
example, a fabric care, surface care or dishwashing
composition.
is '
The present invention also provides a capsule, i.e.
a container, comprising a self-supporting receptacle part
and a closure part, the receptacle part and the closure
part together enclosing a composition, for example a
fabric care, surface care or dishwashing composition, the
receptacle part being formed of a water-soluble polymer,
and the closure part being formed of a water-soluble
polymer, wherein, in use, the closure part dissolves
before the receptacle part.
The present invention additionally provides an
injection-moulded capsule container of any size or shape
for the delivery of a water-destined ingredient,
preferably selected from a fabric care, surface care or
dishwashing composition, which container is made of a
material that will dissolve in the intended aqueous
destination site.
CA 02414395 2002-12-06
_y_
The present invention further provides a method of
ware washing, comprising use of a container, receptacle
or washing capsule as defined above, the method entailing
introducing the container, receptacle or washing capsule
into a ware washing machine prior to commencement of the
washing process, the container, receptacle or washing
capsule being entirely consumed during the washing
process. The ware washing machine may, for example, be a
dishwashing or laundry washing machine.
The present invention also provides a capsule
container comprising at least two components made of one
or more materials) that can be moulded and which are
IS water soluble or water dispersible or in which a
substantial part of the surface of these components is
water soluble or water dispersible so as to leave
perforations throughout the wall when the capsular
container is placed in contact with an aqueous
environment, wherein the container has one to six
compartments, preferably one or two or three, the content
of the various compartments being accessible to the
aqueous environment when the capsular container is
exposed to such an aqueous environment, the accessibility
time of the various compartments being the same or
different from one compartment to another compartment.
The content of. the container may, for example, not be a
fabric care, surface care or dishwashing composition.
The following description and drawings all relate to
each and every aspect and embodiment as discussed above,
either. singly or in any combination thereof.
CA 02414395 2002-12-06
- 1U -
The containers of the present invention overcome ,
some or all of the above disadvantages.
Firstly, because the containers are rigid and self-
supporting, they have an attractive, unifoim appearance
which does not vary between different containers_
Furthermore, the rigid containers can easily have various
elements incorporated which are considered to be pleasing
t0 to the eye but which are impossible to incorporate in the
flexible containers discussed above.
Secondly, because the containers are rigid, it is
easily possible to introduce two or more compartments, or
have larger compartments separated by walls, to separate
mutually incompatible ingredients. The containers can
also hold part of the composition on an external surface,
for example in an indentation: Furthermore, the
container can be moulded is almost any shape that might
be useful. In particular it can be given raised or
lowered areas.
Thirdly, it is possible to control the release
profile of the contents of the container. Since the
container is rigid, it is possible to adapt the width of
all of the walls of the container to control both the
start of release of the composition as well as the rate
of release. For example, one or more walls may be made
thin in order to have an early release of the
composition. Alternatively all the walls may be thick in
order to ensure that there is~a delayed release of the
composition. The rate of release of the.COmpo8ltion may
CA 02414395 2002-12-06
W O 01/36290 _ _ _. _
-11-
also be controlled by ensuring that only part of the
container has thin walls which are dissolved or dispersed'
before the remainder of the container. Different walls
or parts of walls of the container may be prepared from
different water-soluble polymers which have different
dissolution characteristics. For example, a first
compartment may be fully enclosed by a polymer such as
PVOH which dissolves at a higher or lower temperature
than the polymer enclosing a second compartment. 3'hus
1o different components can be released at different times.
If the container holds a solid or gelled composition, it
is not even necessary for the container to fully enclose
the composition. A part may be left exposed, so that it
immediately begins to dissolve when added to water.
is
Fourthly, since the containers are rigid and self-
supporting, they can easily be filled on a production
line using normal filling equipment. Such filling
equipment is quite capable of filling at least 1500
ZO containers per minute.
Desirably the container,~apart from its contents,
consists essentially of the injection-moulded polymer.
It is possible for suitable additives such as
25 plasticizexs and lubricants to bE included. Plasticizers
are generally used in an amount of up tn 20 wt$, for
.. example from 15 to 20 wt$, lubricants are g.enerallly used
in an amount of 0.5 to S$ wt$ and the polymer is
' generally therefore used in an amount of 75 to 89.5 wt$,
30 based on the total amount of the moulding composition.
Examples of suitable polymers are 8t70H anal cellulose
ethers such as HFM.C.
CA 02414395 2002-12-06
-12-
PVOH is a known water-soluble material which is used ,
to prepare water-soluble films for encasing compositions
as discussed above. Cellulose ethers have not in general
been used to prepare water-soluble films because they
have poor mechanical strength.
PVOH materials, unlike gelatin, can be modified to
dissolve at different rates under various conditions
l0 (including the pH of the aqueous medium into which they
are introduced)_
The PVOH preferably used to form the container of
the present invention may be partially or fully
~5 alcoholised or hydrolysed. for example it may be from 40-
100i~, preferably 70-92 %, more preferably about 88%,
alcoholised or hydrolysed poiyvinylacetate. The polymer
such as PVOH or cellulose ether is generally cold water
(20°C) soluble, but may be insoluble in cold water at
ZO ~0°C and only become soluble in warm water or hot water
having a temperature of, for example, 30°C, 40°C, 50°C or
even 60°C. This parameter is determined in the case of
PVOH by its degree of hydrolysis.
25 For certain applications~or uses, polymers soluble
in aqueous environments at temperatures as low as S°C are
also desirable.
In order to ensure that the polymer such as PVOH or
30 cellulose ether is capable of being injection moulded, it
is usual ro incorporate components such as plasticizers
and mould release agents in an amount of up to, for
CA 02414395 2002-12-06
WO OI/3629p ra. am~nnv~~ m
-13-
example, 15 wt$ of the composition. Suitable
plasticiters are, for examples pentaerthyritol such as
depentaerythritol, sorbitol, mannitol, glycerine and
glycols such as glycerol, ethylene glycol and
polyethylene glycol.
Solids such as talc, stearic acid, magnesium
stearate, silicon dioxide, zinc stearate, and colloidal
silica may also be used. A preferred PVOH which is
l0 already in a form suitable for injection moulding is sold
in the form of granules under the name CP1210T~05 by
Soltec Developpement SR of Paris, France.
The PVOH may be moulded at temperatures of, for
!5 example, from 180-220°C, depending upon the formulation
selected and the melt flow index required. It can be
moulded into containers, capsu.7.e bodies, caps,
receptacles and closures of the appropriate hardness.
texture and solubility characteristics.
One of the great practical problems of current hard
gelatine capsules is their ability to hold a static
electrical charge. Such capsules in production rapidly
pick up ~ high static charge which has the effect of
making them not only stick to each other and to all other
non-polar surfaces but also making them attract particles
of foreign material from their surroundings. It also
means that that the capsules are hard to fill, and that
their surfaces must be treated immediately prior t.o
printing. This phenomenon is common to some mouldable
polymers, but not to PVOH, which is not only soluble,
ingestible, mouldable and weldable, but in addition will
CA 02414395 2002-12-06
- 14-
not support a static charge capable of causing the
problems described above. So, yet another consequence of
using an injection-moulding method is that the mouldable
material may be chosen having regard to its ability to
pick up and retain a static charge - or may include one
or more additional substances that has some effect on the
way the capsule behaves in this respect.
Thus, in a still further aspect this invention
provides an injection-moulded container such as a
receptable or capsular container made from materials that
will not hold a static charge, such as PVOH or a
cellulose ether.
One aspect of the present invention is, as indicated
above, a capsule, i.e. a container, comprising a self-
supporting receptacle part and a closure part, the
receptacle part and the closure part together enclosing a
composition such as a fabric care, surface care or
2o dishwasha.ng composition, the receptacle part being formed
of a water-soluble polymer, and the closure part being
formed of a water-soluble polymer, wherein in use, the
closure part dissolves before the receptacle part.
Preferably the capsule is a washing capsule
enclosing a washing composition.
Another aspect of the present invention is, as
indicated above, an injection-moulded capsule container
of any size or shape for delivery of a water-destined
ingredient, in particular selected from a fabric care,
surface care or dishwashing composition, a detergent,
CA 02414395 2002-12-06
w V U 1/.fOLYU a a. . . a. a.vv. vi.r ...
-15-
pesticide, biocide, deodorant, dye, pigment or water-
. treatment chemical. which container is made of a material
that will dissolve in the intended aqueous destination
~ site.
' In many aspects of the present invention, including
these aspects, the water-soluble polymer is not~limited
to PVOH or a cellulose ether. Other water-soluble
compounds may be used, such as polyglycolides, gelatine,
polylactides and polylactide-polyglycolide copolymers.
These components may also, if necessary, contain
components such as.plasticiaers and mould release agents,
such as those described above. All of the polymer
compositions, including the PVOH and cellulose ether, may
also include other components such as colouring agents
and components which modify their properties.
In all aspects and embodiments of the present
invention, the container or capsule generally comprises a
receptacle part which holds the composition and a closure
part, which may simply close the receptacle part or may
itself have at least some receptacle function. The
receptacle part preferably has side walls which terminate
at their upper end in an outward flange in which the
closure part is sealingly secured, especially if the
closure part is in the form of a film. The securement
~ may be by means of an adhesive but is preferably achieved
by means of a seal, between the flange and the closure
' part. Heat sealing may be used or other methods such as
3o infra-red, radio frequency, ultrasonic, laser, solvent,
vibration or spin welding. An adhesive such as an
CA 02414395 2002-12-06
~. v .a.....~..,.
- 16-
aqueous solution of PVOH or a cellulose ether may also be
used. The seal is desirably also Water-soluble.
The closuxe part may itself be injection moulded or .
blow moulded. Preferably, however, it is a plastics film
secured over the receptacle part. The film may, for
example, comprise PVOH or a cellulose ether such as HPMC
or another water-soluble polymer.
The container walls have thicknesses such that the
containers are rigid. For example, the outside walls and
any inside walls which have been injection moulded
independQntly have a thickness of greater than 100Eun, for
example greater than 150~m or greater than ZOO~.cn, 300~m,
t5 or 500~,tm, 750Eun or lmm. Preferably, the closure part is
of a thinner material than the receptacle part. Thus,
typically, the closure part is of thickness in the range
10 to 200 stn, preferably 50 to 100 lun, and the wall
thickness of the receptacle part is in the range 300 to
1500 l.~.m, preferably 500 to 1000 Eun. The closure part
may, however, also have a wall thickness of 300 to 1500
~.un, such as 500 to 1000 ~,un. '
Preferably, the closure part dissolves in water (at
least to the extent of allowing the washing composition
in the receptacle part to be dissolved by the water; and
preferably completely) at 90°C in less than 5 minutes,
preferably in less than 2 minutes.
The receptacle part and the closure part could be of
the same thickness or different thicknesses. The closure
CA 02414395 2002-12-06
wo uyi36z~o . ~.,~..~,...".,...,.
t7 -
part may, for example, be of higher solubility than the
. receptacle part, in order to dissolve more quickly.
Preferably, the washing capsule is generally cuboid
s in its external shape, with the top wall being formed by
the closure part, and with the side walls and base wall
being formed by the receptacle part.
Preferably, a washing capsule of the invention is
l0 manufactured by forming an array of receptacle parts,
each receptacle part being joined to adjacent receptacle
parts, and being separable from them by a snap or tear
action. The array is preferably one which has columns
and tows of the receptacle parts. The receptacle parts
15 may be separated by frangible webs of the water-solublE
polymer such as PVOH or a cellulose ether.
Alternatively, the receptacle parts may be
manufactured with the aforementioned flanges, such that
20 they are separated from each other by a line of weakness.
For example the material may be thinner, and so able to
be broken or torn readily. The thinness may be a result
of the moulding process or, preferably, of a later
scoring step.
as
In the manufacturing method, the axray, formed -by
~ injection moulding, is fed to a filling zone, and ail the
receptacle parts are charged with the washing
composition. A sheet of a water-soluble polymer such as
30 PVOH or a cellulose ether may then be secured over the
top of the array, to form the closure parts for all the
receptacle parts of the array. The array may th8n be
CA 02414395 2002-12-06
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split up into the individual washing capsules, prior to
packaging, or it may be left as an array, for packaging, ,
to be split by the user. Preferably, it is left as an
array, for the user to break or tear oft the individual
washing capsules. Preferably, the array has a line of
symmetry extending between capsules, and the two halves
of the array are folded together, about that line of
symmetry, so that closure parts are in face-to-face
contact. This helps to protect the closure parts from
t0 any damage, between factory and user. It will be
appreciated that the closure parts are more prone to
damage than the receptacle parts. Alternatively two
identical arrays of washing capsules may be placed
together with their closure parts in face-to-face
contact, for packaging.
In some embodiments of the invention the container,
capsule or receptacle part may define a single
compartment. In othex embodiments of the invention the
container, capsule or receptacle part may define two or
more compartments, which contain different products
useful in a washing process. In such a situation a
dividing wall or walls of the compartments preferably
terminate at the top of the container, capsule or
receptacle part i.e. in the same plane as the top edges
of the side walls, so that when the receptacle part is
closed by the closure part the contents of the .
compartments cannot mix. The container, capsule or
receptacle part may be provided with an upstand,
preferably spaced from the side walls thereof, and
preferably of generally cylindrical shape. If wished,
the remaining volume of the container, capsule or
CA 02414395 2002-12-06
W O 01 /36290 rv. m.».......~.. ..,
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receptacle part can be divided into two or more parts by
_ means of walls extending between the upstand and the side
walls.
The container, capsule, receptacle part or closure
may be formed with an opening, for example a depression,
formed in the side wall or the base wall. and preferably
being open in the outward direction. That is to say, it
preferably does not form part of the main volume defined
by the container, capsule, receptacle part or closure.
Preferably the opening is adapted to receive, in a press-
fit manner, a solid block (for example a tablet) of a
composition, for example a material useful in a washing
process.
IS
Preferably, the closure part is of a transparent or
translucent material, so that the contents of the washing
capsule can be seen.
2o Preferably, the container, capsule or receptacle
part is of a transparent or translucent material, so that
the contents of the washing capsule can be seen.
The washing composition within the container,
25 capsule or receptacle part, or within a compartment
thereof, need not be uniform. For example during
manufacture it could be fed first With a settable agent,
for example a gel, useful in a washing process, and then
' with a different material. The first material could
30 dissolve slowly in the washing process so as to deliver
its charge over a long period within the washing process.
This might b~e useful, for .example, to provide immediate,
CA 02414395 2002-12-06
~~ v .a.......~..
-20-
delayed or sustained delivery of a softening agent in a
clothes washing container, capsule or a receptacle part_
The container, or capsule may, for example, be in at
least two parts (a body part and a cap part) which fit
tightly, and preferably sealingly and inseparably,
together to form a compartment in which is stored the
ingredient to be achieved. ~In one example, the container
or capsule may have three parts ' a body such as a
receptacle, a first cap, and then a second cap to fit
over the closed end of either the body or the first cap,
so as to result in a capsule with two separate
compartments. Where there are three such parts (or more;
four parts - a body and three caps - make three
compartments. and so on), then naturally the ingredients
in each compartment may be~the same or they may be
different.
In all embodiments of the present invention one
2o compartment may contain, for example, a liquid or solid
component (such as a powder, granules or a compressed or
gelled tablet) and another may contain a different liquid
or solid component (such as a,powdet, granules or a
compressed or gelled tablet). Alternatively, more than
one component may be present in one or more compartments.
For example a compartment may contain a solid component,
for example in the form of a ball or pill (such as a
powder, granules or a compressed or gelled tablet), and a
liquid component.
By using container, receptacle or capsule cap/body
parts of different thicknesses, or of different polymers,
CA 02414395 2002-12-06
WO 01/36290 rc, rmsisuvu~~ ~o
-21 -
or both, such as PVOH polymers with different degrees of
hydrolysis, this invention enables enhanced control over
the release of different ingredients at different times
. or in different positions within broad scope of the
aqueous destination.
The capsular container can be of any size or shape.
It is, for example, conveniently of the standard capsule
shape - an elongate tubular package with closed, rounded
ends. Moreover, although it i9 possible to have the
several parts of much the same sizes, it is usual that
there will be a long body With a shorter cap (the cap may
be half or a quarter the length of the body). Typically,
a capsular container has an overall closed length of 4 to
IS 10 cm, such as 4 to 6 cm, and an external diameter of 2
to 9 cm. However, it should be understood that there is
no theoretical limitation, in either size or shape, and
what is suitable will normally be decided upon the basis
of the "dose" of the container's contents, the size of
z0 any aperture the container may have to pass through, and
the available means of delivery.
The capsular container may be in at least two parts
(a body or receptacle part and a cap part) which fit
25 tightly, and preferably sealingly and inseparably,
together. The actual joining of the parts can be carried
out in any convenient way, but advantage can be taken of
the very nature of the capsule material - that fact that
it is one that can be injection-moulded (it is a
30 thermoplastic). Thus, the preferred joining method is
welding, for example either heat welding, by melting the
parts when they are in contact, and allowing them to
CA 02414395 2002-12-06
-22-
"run" into each other and then cool and solidify to
become an integral device, or solvent welding, where much _
the same effect is achieved by partially dissolving the
adjacent portions of the capsule and letting them again
3 run into each other and then solidify to form a whole.
Heat welding is much the preferred way, although any of
the sealing techniques described herein may be used.
Indeed, in one of its several aspects the invention
specifically provides an injection-moulded capsular
Contained having a cap portion and a body portion which.
after filling, are welded together into a single
indivisible unit (so sealing in and preventing subsequent
access to the contents, and thus ensuring containment of
the contents, whether solid, powder, granular, liquid,
gel or suspension presentations).
In another aspect, this invention provides a capsule
that may be utilised for the delivery of some active
ingredient or device into the human or animal body, which
capsule is made of a material that can be injection-
moulded and will at least in part dissolve in the body.
The invention provides a capsule - that is to say, a
ZS small container for the relevant ingredients, which
container is in at least two parts (a body part and a cap
part) which fit tightly, and preferably sealingly and
inseparably, together to form a compartment in which is
stored the ingredient to be delivered. As an
alternative, the capsule may have three parts - a body, a
first cap, and then a second cap to fit over the closed
end of either the body or the first cap, so as to result
CA 02414395 2002-12-06
WO 01/36290 ra: irasnvvnrf~ iv
- 23 -
in a capsule with two separate compartments. And where
there are three such parts (or more: four parts - a body
and three caps - make three compartments, arid so an),
, then naturally the ingredients in each compartment may be
the same or they may be different.
In one example - see Figure 11A in the accompanying
Drawings - the capsule may have a body and cap each
provided with a central axially-parallel partition, so
that the capsule as a whole has two separate
compartments.
By using capsule cap/body parts of different
thicknesses, or of different polymers, or both, thin
invention enables enhanced control over the release of
different active ingredients at different times or in
different positions. This difference in release time is
useful in many applications or uses including within the
gastro-intestinal tract, in which the ability to control
release time is of utility in~the developing science of
chrono-biology.
The capsule is of any shape, preferably an elongate
tubular package. The ends are advantageously closed,
whether rounded or conical. Moreover, although it is
possible to have the several parts of much the same
sizes, it is usual that there will be a long body with a
shorter cap (the cap may be half or a quarter the length
of the body). Typically, a capsule has an overall closed
length of 1Q-25mm and an external diameter of 5-lflmm for
pharmaceutical or nutraceutical use.
CA 02414395 2002-12-06
' wv araravow _ . _. __ _ _. _
-24-
Although it is possible to have the several parts of
much the same sizes, it is usual that there will be a
long body with a shorter cap (the cap may be half or a
quarter the length of the body). Typically, a capsular .
5' container for applications or uses other than
pharmaceutical or nutraceuticals has an overall closed
length of 3 to 12 cm, for example 9 to 10 cm and an
external diameter of 1 to 5 cm, for example 2 to 4 cm_
However, it should be understood that there is no
!0 theoretical limitation, in either size or shape, and what
is suitable will normally be decided upon the basis of
the "dose" of the container's contents, the size of any
aperture the container may have to pass through, and the
available means of delivery.
The invention's capsule is intended to be utilised
for the delivery of some active ingredient or device into
the human or animal body. The delivery may be by any
appropriate route; for most active ingredients the oral
route is preferred - and it is when the capsule is
administered orally that its advantages are most apparent
- but rectal or vaginal routes may of course be employed
if appropriate. Regardless of the nature of the route,
however, it is clearly necessary that the material ~rom
which the capsule is made - the material~that can be
injection-moulded - should of course be safe for delivery
into the target organism (which may be a Human or some .
other animal)_ PVOH - polyvinylalcohol - is such a
material: not only is it non-toxic but it is available in '
food-quality grades, and it is very much preferred.
CA 02414395 2002-12-06
WO 01/36290 pc~ric~suuro.~s~o
-25-
PVOH - or more specifically PVOH-based formulations''
- is presently the most convenient injection-mouldable,
water-soluble or water-dispersible, material, and of the
various commercially-available PVOH formulations one
particularly-preferred variety is that range of materials
sold (in the form of granules) under the name CP1210T05
by Soltec Developpement SA of Paris, France
In general, PVOH polymers axe synthetic materials
capable, when appropriately formulated with other
adjuvants - such as plasticisers, particularly glycerine
(but other glycols and polyglycols may be used depending
upon their acceptability for ingestion), and solids such
as talc, stearic acid, magnesium stearate, silicon
dioxide. zinc stearate, and colloidal silica - of being
moulded at temperatures between 180-220°C, depending upon
the formulation selected and the melt flow index
required, into capsule bodies and caps of the appropriate
hardness, texture and solubility characteristics required
of a pharmaceutical or like capsule.
PVOH materials, unlike gelatine, can be modified to
dissolve at different rates under varying conditions
(including the pH of the aqueous medium - such as the
interior parts of the target organism's body - into which
they are introduced). Capsules made from PVOH materials
can therefore be formulated to release their contents in
any desirable location, for example, as far as
pharmaceutical use is concerned, in the stomach, the
3U upper or lower small intestine, or the colon, as
considered desirable.
CA 02414395 2002-12-06
~v vai.wr~..
-26-
Furthermore, PVOH formulations generally do not
interact with many organic solvents or oils of the type ,
used in pharmaceutical or nutraceutical compositions,
while the aqueous gels often utilised in such
compositions can be formulated to resist interaction with
PVOH, so that capsules made from PVOH can be used to
contain such materials.
The invention provides a capsule which is in at
to least two parts (a body part and a cap part) which fit
tightly, and preferably sealingly and inseparably,
together. The actual joining of the parts can be carried
out in any convenient way, but advantage can be taken of
the very nature of the capsule material - the fact that
IS it is one that can be~injection-moulded (it is a
thermoplastic). Thus, the preferred joining method is
welding - either heat welding, by melting the parts when
they are in contact, and allowing them to "run" into each
other and then.cool and solidify to become an integral
20 device, or solvent welding, where much the same effect is
achieved by partially dissolving the adjacent portions of
the capsule and letting them again run into each other
and then solidify to form a whole. Heat welding is much
the preferred way_
Indeed, in one of its several aspects~the invention
specifically provides an injection-moulded capsule
(suitable for use in the delivery of some active
ingredient or device) having a cap portion and a body
3o portion which, after filling, are welded together into a
single indivisible unit (so sealing in and preventing
subsequent access to the contents, and thus ensuring
CA 02414395 2002-12-06
W O U1/3G290 ,....__ .
/'VI/VVv
~ ~~ .
containment of the contents, whether granular, liquid,
gel or suspension presentations).
PVOH materials are particularly suited to thermal
welding, a convenient variety of this technique being
laser welding, though any suitable method can be used
providing it does indeed make a permanent weld with the
polymer used to form the capsule. Some other common
methods are infra-red (IR), radio frequency (RF), and
ultrasonic welding.
Some of these methods may require the addition of
other items or processes to ensure their correct
operation. For example, RF welding may require the use
IS of a metal (normally aluminium) conductor in content with
the capsule surface. Laser welding will normally require
the top surface to be transparent to the laser used, and
the lower surface to be opaque to it. This can be
achieved by avoiding opaque coatings and fillers on the
outer surface of the capsule cap and by their application
to the outer surface of the capsule body. For example, a
circumferential line of a suitable material can be
printed around the body at the required joining point t.o
facilitate the weld at that point. As a result of the
welding, a circumferential weld situation on a planar
cross-section of the capsular container is advantageously
obtained.
~ Of the various methods. the laser wehi is preferred
as there is no direct contact required, and it can
achieve the very high production speeds required.
CA 02414395 2002-12-06
.2g.
After placing the intended contents in the capsule
body, and putting the cap on the body, the two portions .
of the capsule can be welded - by means of a laser beam.
say - into a single unit which cannot thereafter readily .
and without leaving visible traces be separated into body
and cap in order to gain access to the contents.
Accordingly. any attempt to tamper with the_contents
would be clearly obvious.
t0 The two parts of the capsule that are to be welded
together axe, for example, made so that the open end of
one will pass into the open end of the other with the
smallest gap that can be practically achieved to allow
easy assembly. Normally, but nvt necessarily, the
capsule is designed with a stop on one or other component
so that the entry of one into the other cannot overrun
and stops at the same fixed position in every case.
The two halves or shells are in the closed position
when the entire periphery of the open end of one is
overlapped by the periphery of the apen end of the other.
The closed capsule is then ready for welding, and this is
done by bringing the capsule into close proximity to the
welding head. This distance will vary with the method of
welding chosen. The welding equipment is operated, and
forms a weld between the two layers in contact in the
foxm of a line of weld in a closed loop axound the
periphery of the capsule. This an be achieved either by
having the welding heads in the form of a ring (which may
30- be continuous or made up of a number of discrete headsy,
or by rotating one or other of the capsule anal the head
around the other - say, by rolling the capsule past the
CA 02414395 2002-12-06
vw var.aarmv
-29-
head. ~ The exact method will depend on the welding
technology chosen.
, It is also possible to use solvent welding - that
S is, using a solvent ~or the chosen injection-mouldable
material so as to soften and render flowable the surface
layers of the material where the two parts are in
contact. In the PVOH case the solvent is conveniently
water or an aqueous electrolyte solution (typically
l0 containing an alkali metal halide such as lithium
chloride as the electrolyte). This technique, however,
requires another stage to the welding process, in which
the solvent is applied to one of the surfaces to be in
contact before the two shells are closed. This method is
15 not preferred, however, as it is likely to be
comparatively slow, and the addition of water and solute
may well be detrimental to the ingredients) or other
preparations contained within the capsule.
2o The weldability of the two parts (body and cap) of
the injection-moulded capsule,of the invention into a
single unit which cannot subsequently be separated into
its two parts without visibly destroying the capsule is
in contrast to the nature of the known hard gelatine
25 capsule parts, which cannot be so welded. Thus, the
integrity of the contents can be protected by the
invention's capsule in a way which cannot take place
using capsule parts made of gelatine.
30 Due to the integrity of the welded seal, in all
aspects and embodiments the container, receptacle or
CA 02414395 2002-12-06
-30-
capsule can be filled with any appropriate powder,
liquid, gel, or oil.
The invention provides a capsule, container or
s receptacle made of a material, that can be injection-
moulded.' The injection-moulding process allows
controlled variations in the thickness of the walls and
domed ends of either or both halves of the capsule,
thereby allowing the release characteristics to be
infinitely varied. The use of such moulded capsule
shells permits the development of capsule formulations
containing controlled-release beads or granules which can
be determined where the contents are released so that the
system as a whole can be made to deliver its contents at
15 the desired position, rate and period of release
irrespective of differing physioco-chemical properties of
the contents. This also enables the delivery system to
be used to protect the drug acjainst adverse conditions in
other parts of the organism - the gastro-intestinal
20 tract, for example - before absorption occurs.if the
capsule or container is intended for administration to
the human or animal body.
There are many advantages in the production of
25 capsules using injection-moulding as compared with the
traditional dip-coating methods, and it is worth setting
out a few here.
Dip-coating of gelatine is the traditional method
30 for the production of capsule shells. One of the
principal properties of a capsule is the rate at which
the shell material dissolves or disperses to release the
CA 02414395 2002-12-06
WV 01/36Z9U . rc.-nc:~svwumu
-31-
contained ingredients. Using the dipping process there
is only a limited control over the final thickness of the
capsule shell. The principal advantage of using the
injection-moulding process is that there is much greater
versatility over the final component form, for example:-
a) The thickness of the wall sections can be more
closely controlled, and hence may be varied inter
olio to obtain the appropriate dissolution rate of
the capsule.
l0 b) Reduced wall thickness possible with injection-
moulded capsule shells will result in increased
production rates.
c) The surface form (smoothness) of both inner and
outer capsule surfaces can be more closely
t5 controlled for moulded as compared with dipping,
which latter only allows control of the inner
surface form.
d) The degree (tightness) of fit between the two
capsule halves can be more closely controlled with
20 moulding. '
e) Injection-moulding permits the addition ef sectional
variation around the rim of either or both of the
capsule halves, so that features for final capsule
assembly, such as ultrasonic or laser welding, can
25 be included in the basic component design.
f) If both capsule halves are moulded simultaneously,
in the same injection-mould tool, the capsule halves
can be assembled automatically as a post-moulding
operation carried out immediately the tool halves
30 open (with benefits far cleanliness and quality
assurance).
CA 02414395 2002-12-06
-32-
g) There are no requirements for further trimming or
sizing operations.
The invention provides a capsule for the delivery ,
into the human or animal body of an active ingredient or
device- For the most part the ingredient will, as
suggested hereinbefore, be a drug - a pharmaceutically--
active substance - oz perhaps some sort of nutritionally-
active material - a "nutraceutically-active" material -
such as vitamins or oligo-elements or food supplements.
However, it is not impossible for this capsule to be used
for the delivery of quite a different sort of
"ingredient" - for example, a measuring or sampling
device, or machine, as might be required in some forms of
13 medicine or surgery.
In its broadest aspect this invention provides a
capsule made of a material that can be injection-moulded.
This injection-moulding concept has several unexpected
consequences, as does the choice of a polymer of the PVOH
type for this purpose. Specifically, an injection-
moulded capsule can be moulded in almost any shape that
might be useful (as might have been inferred from what
has been said above). In particular, it can be given
23 external raised (or lowered) areas - this has the
advantage that, for the preferred orally delivery route,
it significantly reduces the surface area of the capsule
that is able to come into contact with the walls of the
oesophagus as the capsule is being swallowed, and thereby
reduces the risk of the capsule sticking in the
oesophagus, and thus facilitates the passage of the
capsule down into the stomach.
CA 02414395 2002-12-06
WO 01/36290 ra.. a.as.r..a.v... ~..
- 33 -
In another aspect, therefore, the invention provides
an injection-moulded capsule (suitable for use in the
delivery of some active ingredient or device) havimg
raised portions moulded into its external surface.
Thus the container, capsule, capsular container,
receptacle or closure may, for example, have raised
portions moulded into its external surface.
I0
The raised portions - for the most part they are
referred to hereinafter as "raised", though obviously the
effect of a raised part can be achieved by lowering the
other parts ' can be in the form of short, small pimple-
~5 like projections, or they can be ribs that extend wholly
or partially either around or along the capsule. The
portions may be designed to include or act as markings
allowing identification of the capsule and its contents -
either visually, by the sighted, or tactilely, by the
20 visually-impaired, or even by a machine or reader. 'Thus
a Code can be moulded into the surface so that a filled
capsule can be identified at all stages of its life - by
the manufacturer for quality assurance and quality
control, by a wholesaler or retailer as part of a stock-
25 control system, and by the user before utilisation,
particularly those with vision impairment.
The surface of the capsule, container, receptacle or
closure needs no pre-treatment prior to printing.
By suitable cutting of the moulds used, any required
pattern can be moulded into the surface, either raised or
CA 02414395 2002-12-06
-34-
incuse. Hoth raised and incuse variants bring different
properties to the capsule, and the benefits of each are
described hereinafter. The complexity of the pattern is
limited only by the practical limitations on mould
making.
Thinner areas of the walls of different compartments
of the capsular container are preferably disposed
longitudinally according to the general elongated shape
t0 of the capsular container.
The use of an incuse pattern has a number of
interesting possibilities. For example, for sparingly-
soluble drugs delivered orally, the gastro-intestinal
transit from mouth to rectum is often too short to allow
the active ingredient of some orally-delivered medicament
to be absorbed, with the consequence that most of the
drug is excreted, and so wasted. However, incuse
moulding in a suitable pattern provides a way of
converting the capsule - in, say, the acidic conditions
prevailing in the stomach - from an integral, sealed,
container to a perforate container from which the
contents of the capsule can readily escape as a solution
or suspension (rather like a tea bag, or a metal tea
in fuser) .
Such an incuse pattern design may include a capsule
of standard form but with relatively thick walls. Around
a suitable section of the capsule is moulded an array of .
thin-walled incuse panels. Once the capsule has reached
the stomach, the thin-walled panels in the capsule body
quickly dissolve, leaving the capsule with a grid
CA 02414395 2002-12-06
WO 01/36290 PCT/GIiUUlU4376
-35-
structure of holes. These holes can be small enough to
prevent the internal contents leaving the capsule, but
large enough to allow the dissolving medium to enter and
make contact with the contents of the capsule. As has
been described earlier, PVOH materials can, due to
variations in molecular weight and extent of hydrolysis,
be selected to dissolve at different speeds and at
different temperatures in aqueous conditions. Hence, by
varying the thickness and the dissolution characteristics
Io of the injection-moulded capsule materials, the body of
the capsule may be designed to dissolve or break up at a
chosen rate especially in the stomach. Once the capsule
has dissolved or broken up, the beads or granules are
released but only after being retained in the stomach for
an extended period of up to 12 hours. As long as such
capsules with holes remain intact, they do not pass
through the pyloric sphincter into the duodenum until the
housekeeper wave is in operation.
2o More generally for applications or uses outside of
washing, the difference of accessibility time to an
aqueous environment from one compartment to another is in
the range of Z minute to 12 hours at the same temperature
in the range of 5°C to 95°C.
Another possibility is to mould a capsule in a
relatively sparingly-soluble polymer material - such as a
high molecular weight PVOH having a high degree of
hydrolysis - with a similar array of holes (rather than
thin-walled soluble panels), and then in a separate
process, after filling and capping, to cover the area
containing the holes with a relatively soluble polymer
CA 02414395 2002-12-06
-36-
either by spraying or by shrinking or gluing a soluble
sleeve thereover. It should be noted that in use such a
"covered" perforate capsule may either break up in the
gastro-intestinal tract after being swept from the
3 stomach, thereby releasing its ingredients, or it may
carry on to leave the body in the faeces while still
containing the active-ingredient-carrying beads or
granules (though these have by then been relieved of most
of the active-ingredient content). The relatively-
to sparingly soluble polymer used in this case could even be
an insoluble polymer - provided, of course, that it is
both injection-mouldable and tolerated by the body.
8y this means, such a capsule of outer diameter
15 between 3 and 6 mm may contain, for example, a plurality
of beads slightly larger than the holes which will be
formed in the capsule and on which the finely-divided
sparingly-soluble drug is layered. The drug dissolves
only slowly in the acid conditions prevailing in the
20 stomach. The capsule, because of its size, can be
retained in the stomach and thus allow the release in
solution form of the drug for absorption in the stomach
and gastro-intestinal tract. In this way, the absorption
of the sparingly soluble drug in the gastro-intestinal
25 tract will be increased as the beads are held for a
longer time in the stomach than they would be if released
'from a gelatine capsule that rapidly dissolves with the
result that the beads pass quickly from the stomach into
the small intestine. In the "fed state", units of
30 dimensions greater than 3mm do not pass through the
pyloric sphincter into the duodenum as long as there are
contents in the stomach. Thus, if such a PVOH capsule is
CA 02414395 2002-12-06
~v vuavaw . ~.-....~,.,.._._...
-37-
taken with the breakfast meal, it will be retained in the
stomach until after the evening meal if a normal midday
meal was taken. If the capsule has not dissolved or
broken up in the stomach, it will be swept from the
stomach into the large intestine where it may either
dissolve or break up or be eliminated from the body in
the faeces. The overall result is an increased transit
time of the drug delivery system from mouth to faeces,
and thus increased bio-availability for sparingly-soluble
l0 drugs .
The capsule which either contains or develops holes
while keeping its integrity can also be used
advantageously to retain in the stomach beads containing
IS soluble drugs and possessing controlled-release membranes
programmed to take advantage of the better absorption of
such drugs in the small intestine rather than the large
intestine, and thereby to give a constant rate of
systemic drug input.
These hole-containing or hole-developing capsules
can be used to release two or more drugs at designated
regions each at a controlled relative rate even if the
_ drugs in conventional form have different rates of drug
z5 absorption or metabolism in different regions of the
gastro-intestinal tract.
Whilst the oral route is preferred for may of th.e
drug applications envisaged using the capsules of the
3o invention, the rectal and vaginal routes, particularly
those utilising perforate capsules which produce holes
in vavo, are also important..
CA 02414395 2002-12-06
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The oral route is suitable generally for sparingly-
soluble drugs, and fox good control of drug input and
activation location.
The rectal route is particularly appropriate for use
with perforate capsules that produce holes in vivo,
together with controlled-release drug-carrying beads or
granules. This allows the avoidance of "first pass
metabolism" - some drugs are especially sensitive to this
when administered orally. The perforate capsule can
deliver the drug at s controlled rate via its location in
the rectum so that the drug, unlike the delivery from a
suppository, is released locally from the beads or
granules in the capsule to give a steady, localised,
input into the lower haemorrhoidal vein (unlike the
higher medium and upper haemorrhoidal veins, which
deliver blood to the liver, this allows systemic delivery
without "first pass metabolism" by the liver). If they
were not contained in the capsule, the beads would move
upwards into the descending colon, and so would supply
their drug content mainly to the medial and upper
haemorrhoidal veins. Thus, using the rectal route with a
perforate capsule, a drug can be delivered to a Patient
in a similar but more acceptable manner to that achieved
by intravenous infusion.
The vaginal route with a perforate capsule
facilitates drug delivery at a constant rate followed by
cessation when the system is withdrawn from the body
aperture at the designated time.
CA 02414395 2002-12-06
wo oii36zyu ....,~..,...,.,__._
-39-
From the above examples, other more selective
approaches can be developed to maximise and control the
rate of drug input by the chosen route of product use,
thereby offering solutions to many current problems of
drug delivery in man and other animals.
Another consequence of using an injection-moulding
method is that the mouldable material may easily include'
one or more additional substance that has some effect on
to the way the capsule behaves in uae - for instance, on its
surface properties (and specifically on its tackiness, or
Stickiness), or on its rate of dissolution.
Thus, in yet another aspect the invention provides
an injection-moulded capsule (suitable for use in the
oral delivery of some active ingredient or device) that
is made from an injection-mouldable material that
contains one or more particulate hydrophobic solid in
order to both reduce the surface tackiness and also
2o increase the density of the capsule, which effects will
reduce the risk of the capsule sticking in the
oesophagus.
This meets one of the problems of current hard
gelatine capsules - and of those made of any other water
soluble polymer - namely that upon insertion in the mouth
the capsule comes in contact with water, which will begin
the softening process prior to dissolving and lead to s
stickiness of the surface which can cause problems and
interruptions (sometimes leading to release of its
contents in the oesophagus) on the capsule's path through
the oesophagus to the stomach. As noted, reduction of
CA 02414395 2002-12-06
~~ V VilJVf.7V - v-. ~~--.---. _
-40-
this stickiness can achieved by modifying the mouldable
polymer formulation by the addition of inert solids in ,
powder form - though naturally the added solids have to
be approved fox ingestion, and must be compatible with
the medical preparation contained within the capsule.
This use of added solids provides a more rigid
capsule shell with a surface less immediately affected by
the aqueous content of the mouth or aesophagus, thereby
reducing surface tackiness during the initial swallowing.
In this aspect - the incorporation of a particulate
solid to influence tackiness - the solid is very
preferably extremely finely divided, typical particle
Is sizes being in the range 1-50 micron, and preferably
5-10 micron. The upper limit is generally a practical
one for the moulding process, but with increasing solid
particle size the capsule surface will be to a greater
extent made up of the insoluble solid ingredient and to a
lesser extent the polymer (which will be partially
concealed below the contact surface with the oesophagus).
Materials that can be utilised to reduce the
capsule's surface tackiness are most preferably insoluble
and preferably hydrophobic. Substances suitable for this
purpose are Lalc, stearic acid, magnesium stearate, zinc
stearate, sodium stearate, colloidal silica and magnesium ,
trisilicate. with talc and magnesium Stearate being
especially preferred. '
And in still another aspect the invention provides
an injection-moulded capsule (suitable for use in the
CA 02414395 2002-12-06
WV V!/30iYV _ . _. _-___ _ _. .
-41 -
oral delivery of some active ingredient or device) that
. is made from an injection-mouldable material that
contains one or more particulate solid in order to
accelerate the rate of dissolution of the capsule, for
example in the different conditions of pH which exist in
the gastro-intestinal tract.
Unlike gelatine capsules, which sometimes release
their contents prematurely (especially in elderly
patients) when they stick in the oesophagus and open,
capsules of PVOH (in particular) can be formulated so
that they do not open in the oesophagus but release their
contents only where necessary - ie, when they reach the
relevant target area.
~s
The particulate solid incorporated into the
injection mix may be a material that is barely affected
in a non-acidic medium but dissolves relatively rapidly
in an acidic environment, so as to allow the capsule to
release its contents, for example in the stomach.
Alternatively, the solid material may be one that is
relatively insoluble in an acidic medium but relatively
soluble in a neutral environment, so as to allow release
of the capsule's contents, for example in the lower small
intestine and in the colon.
The simple dissolution of the solid in the chosen
medium is sufficient to cause a significant acceleration
in the capsule break-up, particularly so when a gas is
3d also generated, when the physical agitation caused will
result in the virtually immediate release of the zontents
from the capsule.
CA 02414395 2002-12-06
-42-
Such solids are of course subject to the same
limitations of approval and compatibility as before. The
solids which can be used for accelerating the rate of
dissolution of the capsular container are preferably the
bicarbonate and carbonate salts of the alkali and
alkaline-earth metals, typically sodium, potassium,
magnesium and calcium, all of which salts may liberate
carbon dioxide gas for the purpose of generating
effervescence.
The solid is very preferably extremely finely
divided, typical particle sizes being in the range
1-25 micron, and preferably 5-10 micron_
Materials that can be utilised to affect the
capsule's dissolution rate in a non-acid medium (for
example, the lower intestine or the colon) but without
being affected by an acid medium (for example, the
stomach) are most preferably solid acidic substances with
carboxylic or sulphonic.acid groups or salts thereof.
Substances suitable for this purpose are cinnamic acid,
tartaric acid, mandelic acid, fumaric acid, malefic acid,
malic acid, pamoic acid, citric acid, and naphthalene
disulphonic acid, as free acids or as their alkali or
alkaline-earth metal salts, with tartaric acid, citric
acid, and cinnamic acid in the form of acids or their
alkali metal salts being especially preferred.
One of the great practical problems of current hard
gelatine capsules is their ability~to hold a static
electrical charge. Such capsules in production 'rapidly
CA 02414395 2002-12-06
" W V U lIJOiYU . ~.. m.~.......~.....
- 43 -
pick up a high static charge which has the effect of
making them not only stick to each other and to all other
non-polar surfaces but also making them attract particles
" of foreign material from their surroundings. It also
means that the capsules are hard to fill, and that their
surfaces must be treated immediately prior to printing.
This phenomenon is common to some mouldable
polymers, but not to PVOH, which is not only soluble,
ingestible, mouldable and weldable, but in addition will
not support a static charge capable of causing the
problems described above. So, yet another consequence of
using an injection-moulding method is that the mouldable
material may be chosen having regard to its ability to
pick up and retain a static charge - or may include one
or more additional substance that has some effect on the
way the capsule behaves in this respect_
Thus, in a still further aspect this invention
provides an injection-moulded capsule (suitable for use
in the delivery~of an active ingredient or device into
the human or animal body) being made from materials that
will not hold a static charge.
The capsule of the invention is one that, utilised
for the delivery of some active ingredient or device into
~ the human or animal body, dissolves in the body to
release its contents therein. The term "dissolve" is
' used herein in a fairly general sense, to indicate that
3o the capsule crumbles, decompo9es, disintegrates or
disperses; it need not actually dissolve, although most
often it will.
CA 02414395 2002-12-06
-44-
Another possibility is to mould a capsule, container
or receptacle in a relatively sparingly-soluble polymer
material - such as a high molecular weight PVOH having a
high degree of hydrolysis - with a similar array of holes
(rather than thin-walled soluble panels), and then in a
separate process, after filling and capping, to cover the
area containing the holes with a relatively soluble
polymer either by spraying or by shrinking or gluing a
soluble sleeve thereover. The relatively-sparingly
soluble polymer used in this case could even be an
insoluble polymer - provided, of course, that it is
injection-moudable.
IS Another consequence of using an injection-moulding
method is that the mouldable material may easily include
one or more additional substance that has some effect on
the way the capsule behaves in use - for instance, on its
rate of dissolution.
Thus, in still another aspect the invention provide
a container, for example, relatively-large injection-
moulded capsular container, receptacle, capsule or
closure that is made from an injection-mouldable material
~5 that contains one or more particulate solid in order to
accelerate the rate of dissolution of the container.
This solid may also be present in the contents of the
container, receptacle or capsule.
The simple dissolution of the solid in the chosen
medium is sufficient to cause a significant acceleration
in the container break-up, particularly so if a gas is
CA 02414395 2002-12-06
' WO 01/36390 rv. mva.rmv~...
- 45 -
also generated, when the physical agitation caused will
result in the virtually immediate release of the contents
from the container.
The most obvious solids for this purpose are the
bicarbonate and carbonate salts of the alkali and
alkaline-earth metals, typically sodium, potassium,
magnesium and calcium.
I0 The solid is very preferably extremely finely
divided, typical particle sites being the range 3 to 25
Nm, and preferably 5 to 10 um.
Other materials that can be utilised to affect the
!5 capsule's dissolution rate are most preferably solid
acidic substances with carboxylic or sulphonic acid
groups or salts thereof. Substances suitable for this
purpose are cinnamic acid, tartaric acid, mandelic acid,
fumaric acid, maleic acid, malic acid, pamoic acid,
20 citric acid and naphthalene disulphonic acid, as free
acids or as their alkali or alkaline-earth metal salts,
with tartaric acid, citric acid, and cinnamic acid in the
form of acids or their alkali metal salts being
especially preferred.
~5
The container or capsule of the present invention
may contain any composition which is intended to be
released when the container is placed in an aqueous
environment.
Thus it may, for example,' contain a fabric care,
surface care or dishwashing composition. A fabric care
CA 02414395 2002-12-06
-46-
composition is any composition which is used in the field
of fabric care, such as in a fabric washing, fabric
treating or dyeing process. A surface care composition
is any composition which is used in the field of surface
care, for example to clear, treat or polish a surface.
Suitable surfaces are, for example, household surfaces
such as worktops, as well as surfaces of sanitary ware,
such as sinks, basins and lavatories. A dishwashing
composition is any composition which is used in the field
IO of dishwashing, such as a dishwashing, water-softening or
rinse aid composition.
Examples of such compositions are a dishwashing,
water-softening, laundry, detergent and rinse-aid
IS compositions. In this case the composition is especially
suitable for use in a domestic washing machine such as a
clothes washing machine or dishwashing machine. Other
examples are disinfectant, antibacterial and antiseptic
composition, for example those intended to be diluted
20 with water before use, or a concentrated refill
composi.tivn, for example for a trigger-type spray used 3n
domestic situations. Such a composition can simply be
added to water already held in the spray container.
25 The container may be used to contain any
composition. Desirably the composition has a mass of at
least 10 g or 15 g, for example, from 10 g or 15 g to
100 g, especially from 10 g to 15 g to 90 g. For
example, a dishwashing composition may weigh from 10 g or .
30 15 g to 20 g, a water-softening composition may weigh
from 25 g to 35 g, and a laundry composition may weigh
from 10 g to 90 g, 20 g to 40 g or 30 g to ~0 g.
CA 02414395 2002-12-06
..v var....~i..
-47-
The container may also contain, for example, a
detergent, pesticide, biocide, deodorant, dye, pigment or
water-treatment chemical. It may, for example, deliver
detergents or water-treatment chemicals to a washing
machine.
For pharmaceutical or nutraceutical applications or
uses, the typical mass of the contents of the capsular
l0 container is in the range of 10 mg to 15 g, preferably
50 mg to 1 g.
For uses other than pharmaceutical, nutraceutical or
washing, the typical mass of the contents of the capsular
container is in the range of 1 g to 100 g, preferably 2 g
to 50 g-
In general, particularly when used in a domestic
environment, the maximum dimension of the container is 5
cm. For example, a cuboid container may have~a length of
1 to 5 cm, especially 3.5 to 4.5 cm, a width of 1.5 to
3.5 cm, especially 2 to 3 cm, and a height of 1 to 2 cm.
especially 1.25 to 1.75 cm.
The composition contained~by the capsule may be, for
example, any which is suitable for the designated
application, for example a clothes washing or dishwashing
application. It may be a powder or a liquid but if a
liquid, may be a low water formulation, preferably having
a maximum water content of 5 wt%, in order to maintain
the integrity of th.e walls of the capsule or a higher
water formulation containing. for example, at least 8 wt~
CA 02414395 2002-12-06
-48-
water. The composition may be formulated having regard
to the fact that the user will not come into contact with
the composition, whether by inhalation or by skin
contact. For example, the composition may include an
enzyme. without concern about physical contact between
the composition containing the enzyme, and the user.
If the container contains an aqueous liquid having a
relatively high water content, it may be necessary to
t0 take steps to ensure the liquid does not attack the
water-soluble polymer if it is soluble in cold water
(20°C), ox water at a temperature of up to, say, 35°C.
Steps may be taken to treat~the inside surfaces of the
container, for example by coating it with agents such as
PVdC (poly(vinylidene chloride))or PTFE
(polytetrafluoroethylene). or to adapt the composition to
ensure that it does not dissolve the polymer. For
example, it has been found that ensuring the composition
has a high ionic strength or contains an agent which
minimises water loss through the walls of the container
will prevent the composition from dissolving the polymer
from the inside. This is described.in more detail in EP-
A-518,689 and WO 97/27793.
The composition held within the container depends,
of course, on the intended use of the composition. It
may, for example, contain surface active agents such as .
an anionic, non-ionic, cationic,~amphoteric or
awitterionic surface active agent or mixture thereof.
Examples of anionic surfactants are straight-chained
or branched alkyl sulfates and alkyl polyalkoxylated
CA 02414395 2002-12-06
' W V U1/:f019U rv. aivasvwv~a w
-49-
sulfates, also known as alkyl ether sulfates. Such
surfactants may be produced by the sulfation of higher
Ce-Czo fatty alcohols.
Examples of primary alkyl sulfate surfactants are
those of formula:
ROS03-M+
wherein R is a linear Ce-Czo hydrocarbyl group and M is a
water-solubilising cation_ Preferably R is Cio-Cis alkyl,
for example Clz-C~a, and M is alkali metal such as
lithium, sodium or potassium.
Examples of secondary alkyl sulfate surfactants are
those which have the sulfate moiety on a "backbone" of
the molecule, for example those of formula:
CHz ( CHz ) n ( CHOS03-M+) ( CHz ) a,CH3
wherein m.and n are independently 2 or more, the sum of
m+n typically being 6 to 2U, for example 9 to 15, and M
is a water-solubilising cation such as lithium, sodium or
potassium.
Especially preferred secondary alkyl sulfates are
the (2.3) alkyl sulfate surfactants of formulae:
CHZ ( CHZ ) x ( CHOS03-M~ ) CH3 and
CH3 (CHz) X (CHOS03 M+) CHZCH3
for the 2-sulfate and 3-sulfate, respectively. In these
- formulae x is at least 9, for example 6 to 20, preferably
10 to 16. M is cation, such as an alkali metal, fox
example lithium, sodium or potassium.
CA 02414395 2002-12-06
-so-
Examples of alkoxylated alkyl sulfates are
ethox ylated alkyl sulfates of the formula:
RO (CZHaO) nS03-M' ,
wherein R is a C8-Czo alkyl group, preferably Cao-Cae such
as a Caz-Cas. n is at least 1, for example from 1 to 20,
preferably 1 to 15, especially 1 to 6, and M is a salt-
forming cation such as lithium, sodium, potassium,
ammonium, alkylammonium or alkanolammoniurn. These
compounds can provide especially desirable fabric
cleaning performance benefits when used in combination
with alkyl sulfates.
13 The alkyl sulfates and alkyl ether sulfates will
generally be used in the form of mixtures comprising
varying alkyl chain Jengths and, if present, varying
degrees of alkoxylation.
Other anionic surfactants which may be employed are
salts of fatty acids, for example Ce-Cie fatty acids,
especially the sodium potassium it alkanolammonium salts,
and alkyl, for example C8-Cae, benzQne sulfonates .
Examples of nonionic surfactants are fatty acid
alkoxylates, such as fatty acid ethoxylates, especially
those of formula: ,
R(C2H40)~OH '
'
wherein R is a. straight or branched C8-C16 alkyl group,
preferably a C9-Cas, for example Cao-Caa. or Ciz-Cao alkyl
CA 02414395 2002-12-06
WU U1/3G29U rte. r m~n.mn.~ ...
- S1 -
group and n is at least 1, for example from 1 to 16,
preferably 2 to 12, more preferably 3 to 10.
The alkoxylated fatty alcohol nonionic surfactant
will frequently have a hydrophilic-lipophilic balance
(HLB) which ranges from 3 to 17, more preferably from 6
to 15, most preferably from 10 to 15.
Examples of fatty alcohol ethoxylates are those mx~de
from alcohois of 12 to 15 carbon atoms and which contain
about 7 moles of ethylene oxide. Such materials are
commercially marketed under the trademarks Neodol 25-7
and Neodol 23-6.5 by Shell Chemical Company. Other
useful Neodols include Neodol 1-S, an ethoxylated fatty
alcohol averaging 11 carbon atoms in its alkyl chain with
about 5 moles of ethylene oxide; Neodol 23-9, an
ethoxylated primary Clz-C13 alcohol having about 9 moles
of ethylene oxide; and Neodol 91-10, an ethoxylated C9-Cm
primary alcohol having about 10 moles of ethylene oxide.
Alcohol ethoxylates of thi3 type have also been
marketed by Shell Chemical Company under the Dobanol
trademark. Dobanol 91-5 is an ethoxyleted C9-Cm fatty
alcohol with an average of 5 moles ethylene oxide a-nd
Dobanol 25-? is an ethoxylated ClZ-C15 fatty alcohol with
an average of 7 moles of ethylene oxide per mole of fatty
alcohol.
Other examples of suitable ethoxylated alcohol
34 nonionic surfactants include Tergitol 15-S-? and Ter'gitol
15-S-9, both of which are linear secondary alcohol
ethoxylates available from Union Carbide Corporation_
CA 02414395 2002-12-06
-52-
Tergitol 15-S-7 is a mixed ethoxylated product of a C11-
C15 linear secondary alkanol with 7 moles of ethylene
oxide and Tergitol 15-S-9 is the same but with 9 moles of
ethylene oxide.
Other suitable alcohol ethoxylated nonionic
surfactants are Neodol 45-11, which is a similar ethylene
oxide condensation products of a.fatty alcohol having 14-
carbon atoms and the number of ethylene oxide groups
10 per mole being about 11. Such products are also
available from Shell Chemical Company.
further nonionic surfactants are, for example, Clo-
Cle alkyl polyglycosides, such s C12-Cis alkyl
13 polyglycosides, especially the polyglucosides. These are
especially useful when high foaming compositions are
desired. Further surfactants are polyhydroxy fatty acid
amides. such as Clo-Cue N-(3-methoxypropyl) glycamides and
ethylene oxide-propylene oxide block polymers of the
Pluronic type.
Examples of cationic surfactants are those of the
quaternary aitunonium type .
Examples of amphoteric surfactants are Clo-C18 amine
oxides and the C12-Cie betaines and sulfobetaines .
The total content of surfactants in the laundry or
detergent composition is desirably 60 to 95 wt%,
especially 75 to 90 wt%. Desirably an anionic surfactant
is present in an amount of 50 to 75 wt%, the nonionic
surfactant is present in an amount of 5 to 20 wt%, the
CA 02414395 2002-12-06
WO 01/36290 r~. aiuasvviu~oiv
-53-
cationic surfactant is present in an amount of from 0 to
wt$ and/or the amphoteric surfactant is present in the
amount of from 0 to 10 wt%. These amounts are based on
the total solids content of the composition, i.e.
5 excluding the water when present.
Dishwasher compositions usually comprise a
detergency builder. Suitable builders axe alkali metal
or ammonium phosphates, polyphosphates, phosphonates,
10 polyphosphonates, carbonates, bicarbonates, borates,
polyhydroxysulfonates, polyscetates, earboxylates such as
citrates and other polycarboxylates. The builder is
desirably present in an amount of up to 90 wt%,
preferably 15 to 90 wt%, more preferably 15 to 75 wt%,
relative to the total weight of the composition. Further
details of suitable components are given in, for example,
EP-A-699,059, EP-A-518,720 and WO 99/06522.
The compositions, particularly when used as laundry
washing or dishwashing compositions, may also comprise
enzymes, such as protease, lipase, amylase and cellulase
enzymes. Such enzymes are commercially available and
sold, for example, under the registered trade marks
Esperase, Alcalase, Savinase, Termamyl, Lipolas.e and
Celluzyme by Nova Nordisk A/S. Desirably the enzymes are
present in the composition in'an amount of from D.S to 3
wt%, especially 1 to 2 wt%.
The compositions may, if desired, comprise a
thickening agent or gelling agent. Suitable thickeners
are polyacrylate polymers such as those sold under the
trade mar~C CAR$OPOL, or the trade mark ACUSOL by Rohm and
CA 02414395 2002-12-06
-54-
Hass Company. Other suitable thickeners are xanthan
gums. The thickener, if present, is generally present in
an amount of from 0.2 to 4 wt$, especially 0.2 to 2 wt%.
The compositions-can also optionally comprise one or
more additional ingredients. These include .conventional
detergent composition components such as further
surfactants, bleaches, bleach enhancing agents, builders,
suds boosters or suds suppressors, anti-tarnish and anti
!0 corrosion agents, organic solvents, co-solvents, phase
stabilisers, emulsifying agents, preservatives, soil
suspending agents, soil release agents, germicides,
phosphates such as sodium tripolyphosphate or potassium
tripolyphosphate, pH adjusting agents or buffers, non-
builder alkalinity sources, chelating agents, clays such
as smectite clays, enzyme stabilizers, anti-limescale
' agents, colourants, dyes, hydrotropes, dye transfer
inhibiting agents, brighteners, and perfumes. If used,
such optional ingredients will generally constitute no
more than 10 wt~s, for example from 1 to 6 wt%, the total
weight of the-compositions.
The builders counteract the effects of calcium, or
other ion, water hardness encountered during laundering
or bleaching use o~,,the compositions herein. Examples of
such materials are citrate, succinate, malonate,
carboxymethyl succinate, carboxylate, polycarboxylate and
polyacetyl carboxylate salts, for example with alkali
metal or alkaline earth metal cations, or the
corresponding free acids. Specific examples are sodium,
potassium and lithium salts of oxydisuccin~c acid,
mellitic acid, benzene polycarboxylie acids, Coo-CZZ fatty
CA 02414395 2002-12-06
wo oii3sa9o . _......._....,
. ,....,...
-55-
acids and citric~acid. Other examples are organic
phosphonate type sequestering agents such as those sold
by Monsanto under the trade mark bequest and alkylhydroxy
phosphonates. Citrate salts and ClZ-Cia fatty acid soaps
are preferred.
Other suitable builders are polymers and copolymers
known to have builder properties. For example, such
materials include appropriate polyacrylic acid,
to polymaleic acid, and polyacrylic/polymaleic and
copolymers and their salts, such as those sold by BASF
under the trade mark Sokalan.
The builders generally constitute from 0 to 3 wt%,
more preferably from 0.1 to 1 wt%, . by weight of the
compositions.
Compositions which comprise an enzyme may optionally
contain materials which maintain the stability of the
enzyme. Such enzyme stabilizers include, for example, '
polyols such as propylene glycol, boric acid and borax.
Combinations of these enzyme stabilizers rnay also be
employed. If utilized, the enzyme stabilizers generally
constitute from 0.1 to 1 wt~ of the compositions.
The compositions may optionally comprise materials
which serve as phase stabilizers and/or co-solvents.
Example are Cl-C3 alcohols or diols such as methanol,
ethanol, prapanol and 1,2-propanediol. C1-C9
alkanolamines such as mono-, di- and triethanolaminea and
monoisopropanolamine can also be used, by themselves or
in combination with the alcohols.
CA 02414395 2002-12-06
56 -
If the composition is in liquid form, it may b~
anhydrous, or, for example, contain up to 5 wt% water.
Aqueous compositions generally contain greater than 8 wt%
water based on the weight of the aqueous composition.
Desirably the aqueous compositions contain more than 10
wt%, 15 wt%, 20 wt%, 25 wt~ or 30 wt% water, but
desirably less than 80 wt% water, more desirably less
. than 70 wt$, 60 wt%, 50 wt% or 90 wt% water. They may,
t0 for example, contain from 30 to 65 wt% water.
The compositions may optionally comprise components
which adjust or maintain the pH of the compositions at
optimum levels. Examples. of pH adjusting agents are NaOH
and citric acid. The pH may be from, for example, 1 to
13, such as 8 to 11 depending~on the nature of the
composition. For example, a dishwashing composition
desirably has a pH of 8 to 11, a laundry composition
desirably has s pH of 7 to 9, and a water-softening
composition desirably has a pH of 7 to 9.
The composition, such as a washing composition
within the container, capsule or receptacle part, or
within a compartment thereof if there is more than one
compartment, need not be uniform. For example during
manufacture it could be fed first with a settable agent,
for example a gel, useful in a washing process, and then .
with a different material. The first material could
dissolve slowly in the washing process so as to deliver
3o its charge over a long period within the washing process.
This might be useful, for example, to provide delayed or
CA 02414395 2002-12-06
WO 117/3G29U 1'a. aivamnvi~,o
- ST -
sustained delivery of a softening agent in a clothes
washing capsule.
The composition, such a5 a washing composition may,
especially for dishwashing or laundry, include a tablet.
Preferably a tablet contains a material useful in a
washing process and is formulated to provide slow release
of that material during a washing process and/or delayed
release thereof. Delayed release may be achieved by
providing the tablet with a coating which is slow to
dissolve during the washing process. Alternatively the
tablet may provide a quick release of components required
early in the wash, for example water-softening components
and/or enzymes. The tablet may, for example, comprise a
disrupting agent, such as one which effervesces when in
contact with water such as a combination of citric acid
and an alkali metal carbonate or bicarbonate.
A tablet may be provided in the main volume of the
receptacle part or may be provided in an outwardly facing
opening or depression, as previously described.
When a washing capsule of the invention has a tablet
retained in an outwardly,facing opening or depression the
tablet is preferably one which will not transfer any '
washing composition to the hands of a user. For example,
it may be coated with a soluble polymeric material. As
mentioned above, this may also be desirable for delayed
release of its charge. If iC is desired that the tablet
dissolves quickly it may, for example, comprise a
disrupting agent such as an effervescing agent.
CA 02414395 2002-12-06
-58-
In accordance with a further aspect of the invention
there is provided a method of ware washing, comprising
use of a container, receptacle or washing capsule as
described and defined above, the method entailing .
introducing the container, receptacle or washing capsule
into a ware washing machine such as a laundry washing
machine or dishwashing machine, prior to commencement of
the washing process,. the container, receptacle or washing
capsule being entirely consumed during the washing
process.
The invention also provides a capsule - that is to
say, a container for the relevant ingredients, which
container is in at least two parts (a body part and a cap
' part) which fit tightly, and preferably sealingly and '
inseparably, together to form a compartment in which is
stored the ingredient to be delivered. In one example -
see Figure 11A in the accompany~_ng Drawings - the capsule
may have a body and cap each provided with a central
axially-parallel partition, so that the capsule as a
whole has two separate compartments. In another example
the capsule may have three parts - a body, a first cap,
and then a second cap to fit over the closed end of
either the body or the first~cap, so as again to result
in a capsule with two separate compartments. And where
there are two or three such parts (or more; four parts -
a body and three caps - make three compartments, and so
on), then naturally the ingredients in each compartment
may be the same or they may be different.
The capsule of the invention is one that dissolves
in the destined aqueous medium to release its contents
CA 02414395 2002-12-06
~ W V V l/JOLyV _ . _. _- _ _. -
- 59
therein. The term "dissolve" is. used herein in a fairly
general sense, to indicate that the capsule crumbles,
decomposes, disintegrates or disperses; it need not
actually dissolve, although in most cases it will.
The invention will now be further described. by way
of example, with reference to the accompanying drawings
in which.
Fig. 1 is a perspective view, generally from above,
of an array of receptacle parts;
Fig. 2 is a perspective view, generally from above,
of an alternative array of receptacle parts:
Fig. 3 is a perspective view of some of the parts
shown in Fig. 2, but looking generally from underneath;
Fig. 9 is a perspective view, generally from above,
of a third embodiment of receptacle part;
Fig. 5 is a perspective view, generally from above,
of the Fig. 9 embodiment, but filled with washing
composition and closed over by a closure part, to form a
washing capsule of the invention;
Fig. 6 is a perspective view from above of a fourth
embodiment of receptacle part; and .
Fig. 7 is a perspective view from below of
receptacle parts of the type shown in Fig. 6.
CA 02414395 2002-12-06
n v vii..v.av
-60-
Fig. 8A & 8 show longitudinal cross-sections of a
capsular container of the invention in its open and
closed states respectively:
Fig. 9 shows the closed capsular container of Fig.
8B but in see-through perspective;
Fig. 10A ~ 8 show longitudinal cross-sections of
two- and three-compartment capsular containers of the
f0 invention;
Fig. lIA ~ H show respectively longitudinal and
transverse cross-sections of another two-compartment
capsular container of the invention;
Fig. 12 shows a section through the wall of a solid-
filled polymer capsule of the invention:
Fig. 13A-M show various different forms of moulding
an and in the surface of capsular containers of the
invention.
Fig. 1 shows an array of~eight receptacle parts 2,
arranged as two columns and four rows. Each receptacle
part has a flat base wall without indentations or
recesses and four uprights side walls 4, and has no top
wall. Thus, each receptacle part is upwardly open.
Around its opening, at the top of the side walls 4, is an
outwardly-directed flange 6, which extends around the
3o entire opening. The receptacle parts are joined to
adjacent receptacle parts by webs 8 between the flanges
6. The flanges 6 of all of the receptacle ,parts lie in
CA 02414395 2002-12-06
WO 01/31290 iv iivwW v~.r.v
-61 -
one plane. The base walls of all of the receptacle parts
also lie in one place, parallel to the plane in which the
flanges lie.
The array shown in the drawing is made by injection
moulding. The thermoplastic polymer employed in this
embodiment is polyvinyl alcohol, and is translucent. The
wall thickness is about 0.7 mm. The resulting moulded
array is self-supporting.
After injection moulding score lines may be cut into
the webs 8 between the flanges, to aid the breaking apart
of the washing capsules, for use.
The moulded array is fed.to a filling zone where the
receptacle parts are simultaneously filled via eight
nozzles, with a dishwashing composition. The dishwashing
composition could be a powder, gel or paste or could be a
liquid formulation. if it is a liquid it may be a liquid
formulation of relatively low water content, fox example,
2 to 5 wt%, given the properties of the polymer.
Alternatively the water content may be higher, for
example up to 60 wt% or .even BO wt%, so long as the pVOH
is not attacked by the composition. Such steps are
described above. A translucent cover film is then laid
over the array and heat sealed against the flanges 6, so
that each receptacle part has, over it, a closure part.
The closure part is also of polyvinyl alcohol, but is
much thinner, about 80 Eam in this embodiment.
Although the film which constitutes the closure
parts is tough it will be appreciated that it is
CA 02414395 2002-12-06
' WO 01/36290 "...__ . _
. ........,.
- 62 -
generally less robust than the receptacle parts. In this
case, before packaging the product, the capsules may be
put into face-to-face contact. An array of washing
capsules identical to that of the drawing may be placed
in face-to-face contact with it. Alternatively, and
conveniently, the array shown in the drawing may be
folded about line A-A shown in~Fig. 1.
The drawing illustrates the invention but in
practice an array of receptacle parts is likely to be
considerably larger. Nevertheless, the manufacturing
method would be as described.
In use, a user will simply break off a washing
capsule from the array, and put it in, the dishwashing
machine. During the washing process the entire washing
capsule will dissolve. The first part to dissolve will
generally be the closure part_ This may happen very
9uickly once the washing process starts and the washing
composition will immediately be delivered. The
. receptacle part will generally dissolve more slowly but
it will have dissolved entirely by the end of Che washing
process.
Figs. 2 and 3 show an alternative embodiment of the
receptacle paxts. The receptacle parts shown in Figs. 2
and 3 are of similar shape and size to those shown in-
Fig. 1, but have, within the main chamber defined by the
base wall and side walls of each receptacle part, a
3Q generally cylindrical upstand 10, in a central position.
Each upstand is open at its upper end, and its upper end
is in the same plane as the flange 6.
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As shown in Fig. 3, each receptacle part also has a
depression I2 at a central position in its base wall.
The depression is relatively shallow, and it is aligned
with the upstand 10 carried by the base wall on its other
side. Each depression contains within it a tablet 19.
Each tablet contains a washing composition yr a material
which forms part of a washing composition, but is
formulated for quick release, slow release and/or delayed
release. For slow release it may b.e a tablet which
dissolves over an extended period. For delayed release
it may be a table coated with a polymeric coating which
is slow to dissolve, so that it releases its charge in
the middle or towards the end of a washing cycle.
~s
Another difference between the embodiment of Fig. 2
and that of Fig. 1 is that in the Fig. 2 embodiment there
is a plurality of breakable webs 16 of polymeric material
extending between the flanges of adjacent receptacle
z0 parts .
The array shown in Figs.?_ and 3 is again made by
infection moulding, using HPMC polymer. having a wall
thickness of about 0.8 mm, although PVOH, for example,
z5 may also be used. Tablets Z4 are press-fitted into the
depressions 12 in the undersides of the base walls. The
array is then inverted for filling. The upstands 10 are
filled with one material. and the remaining volumes,
between the upstands and the side walls of the respective
3o receptacle parts, are filled with another material. A
cover film is then laid over the array and heat sealed
against the flanges 6 and against the ends of the
CA 02414395 2002-12-06
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upstands 10, so that each receptacle part has, over it, a
closure part. The closure part is of HPMC, about 70
microns thick. Again, PVOH may, for example, also be
used.
The embodiment shown in Figs. 4 and 5 is similar to
that of Figs. 2 and 3 in having an upstand. However the
remaining volume of the receptacle part is divided into
two by means of walls 18, 20, extending from the u~pstand
in opposed directions, and with each connecting with a
respective side wall of the receptacle part. It will be
apparent that the receptacle part comprises thr~e main
chambers whose contents are released into the washing
water once the closure part dissolves. One Chamber 22 is
~5 defined within the upstand and the other chambers 24, 26
are of identical size to each other and are defined
between the upstand and the side walls. The underside of
the receptacle part may, like.the embodiment of Figs. 2
and 3, comprise a central depression into which is
pressed a tablet. The receptacle parts are formed, in an
array, by injection moulding.
Fig. 5 shows a washing capsule which uses the
receptacle part shown in Fig. 9. The receptacle part has
been filled with three different materials useful in a
dishwashing cycle and a cover film is shown in place.
The embodiment of Figs_ 6 and 7 is simpler than
those of Figs. 2 to 5. The receptacle part shown does
not hare a central upstand. There is one main volume.
However the underside of the base wall is moulded with a
depression and into this depression is press-fitted a
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tablet. I'n the embodiment of~Figs. 6 and 7 the main
chamber of the receptacle part can be filled with two or
more gels which stay separate, for example, side by side,
or one within the other, or in the form of separate
stripes. The receptacle parts of Figs. 6 and 7 may be
formed, in an array, by vacuum forming.
In the embodiments of Figs_ 4 to 7 the materials
selected for the receptacle parts and closure parts, and
their thicknesses, are as described for the Fig. 1
embodiment.
Figure 8 shows a two-part, one compartment capsular
container of the invention in~its open and its closed
l5 form.
The body (1I1) and cap (112) are to be welded
together and are made so that the open end (111a) of one
will pass into the open end (112a) of the other with the
smallest gap that can be practically achieved to allow
easy assembly. There is a "stop" - a ridge (lllb)
running all round outside of the body 111 that co-
operates with a groove (112b) running all round the
inside of the cap 112 - so that the entry of one into the
other cannot overrun, and stops at the same fixed
position in every case. '
When the two halves or shells 111, 112 are in the
closed position (as in Figure 8B), with the entire
periphery of the open end llla of the body 111 overlapped
by the periphery of the open end 112a of the cap 112, the
capsular container is ready for welding. The welding
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equipment (not shown) foams a weld line (113) between the
two layers all round the periphery of the container.
Figures 10 and 11 show different sorts of multi- .
s compartment capsular container according to the
invention.
In Figure 10 the container is made in two or more
parts (three in Figure 10A, four axe shown in Figure IOB,
but there could be more) - in each case there is a single
cap portion (132) and a plurality of body portions (as
131). The outer of the body portions 131 is much the
same as an "ordinary" body portion (as in Figure 8), but
each inner one is shaped at its "outer" end (131c) so
that it will fit tightly inside the open mouth of the
next body portion, much like in Figure 8 the body 111
fits inside the cap 112.
As shown (in Figure 10A), when the first (outer)
body part 131 has been filled with product A, it may then
be closed by the second (inner) body part 131 within it.
That second body part 131 may then be filled with product
B, the cap 132 placed in position, and the three parts
welded together at the same time.
Figure 11 shows a capsular container with body (191)
and cap (142) two compartments side-by-side (Figure 11B .
shows a transverse section on the line A-A in Figure
11A). The two compartments can of course hold different '
products (A and B) .
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There is theoretically no limit to the number of
separa to chambers that can be produced either linearly
(as in Figure 10) or side by side within the body portion
(as in Figure 11). Of course, limitations will be set by
S practi cal problems of manufacture.
In figure 12 there is shown a section through the.
wall of a solid-filled polymer capsular container of the
invention.
io
Inert solids in powder form have been added to the
polymer formulation prior to moulding. This provides a
more rigid shell. It especially providea~a more rigid
capsule shell with a surface less immediately affected by
~5 the aqueous content of the mouth or oesophagus, thereby
reducing surface tackiness during the initial swallowing.
The Capsule surface is to a significant extent made up of
the particulate insoluble solid ingZiedient (as 159); the
soluble polymer (155) is partially concealed below the
20 contact surface (156) .
Figure 13 etc show various different forms of
moulding on the surface of capsular containrers of the
invention, some in the form of czoss-sections.
Z5
These are sell-evident, and need little comment.
Figure 13A, F, for example, shows a capsular container
with longitudinal raised ribs, while Figuze 13$ shows one
with lateral (or circumferential) raised ribs and FigurQ
30 13E shows one with helical ribs. Figure 13C, H shows a
container with raised pimples. while Figurre 13D, I stows
one with raised identification coding patterns. figures
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13G, J, K, L and M show variants analogues to some of the
others, but with incuse rather than raised portions.
The invention is further explained in the following
Examples.
ERAMPLE3
Example l:
t0 The manufacture of capsules by infection moulding and
laser welding
The moulding stage
Capsules according to the invention were made by the
injection moulding method utilising an Arborg 220D
(35 tonne) injection moulding machine. The injection
cavities were in a two-impression (cap/body) composite
water-cooled stainless-steel mould. The PVOH had a
material melt flow index of 10-20 grams per 10 minx,
(DIN 53735).
Injection temperatures were 175°C, 180°C, 180°C and
185°C in the feed, zone 2 and 3, and Nozzle areas. The
first stage injection pressure was 400psi (.__..), and
the hold stage pressure was 270psi (......). The
pressure well time was 3 sacs in the first stage and
5 sacs in the hold stage. Toal temperatures were between
ambient and 90°C.
The moulding pressures were just sufficient to fill
the cavities on the first pressure stage and then
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sufficient packing pressure to hold on the second stage.
Mould open and close rates wefe as fast as possible.
As noted, the mould layout was divided into two
halves, one half moulding capsule bases and the other
half capsule caps. After the mould opening sequence, two
robotically controlled loading plates pneumatically
picked up each capsule half from each tool face. With
identical cavity pitch centres, these loading plates were
t0 brought together so that each capsule half was located
resulting in the usual temporary location of the pair
ready for automatic filling.
The filling stage
For test purposes the capsules were filled by hand
with various test materials (see below).
The welding stage
The closed capsule is introduced into a transparent
tube with an internal diameter not more than 20~ greater
than the external diameter of the capsule. An array of
diodes is located circumferentially arflund the outside of
the tube. As the capsule passes by the diode array, a
weld is formed. The velocity of the capsule and the
power of the IR emitted by the diode array provide the
necessary control over the melting process. The IR
emission is either continuous or discontinuous. In the
case of discontinuous emission, this is achieved by
synchronisation of switching depending on the form of
CA 02414395 2002-12-06
weld required and the sensitivity of the contents of the
capsule to the IR.
If the characteristics of the material contained .
within the capsule are such that they absorb the IR,
switching of the laser. is necessary such that exposure to
the IR is limited to the area of the join. This is
effected by means of electrical switching or, in a
further embodiment, by a form of optical switching using
0 a lens/prism arrangement. In order.tv overcome the
difficulty of synchronisation, again optical fibre
delivery of the IR is used to'restrict the area of
exposure.
Example 2:
The manufacture of capsules using laser welding
In an alternative laser welding stage, the laser or
other IR source is arranged to focus on the area of the
join. This does not create 'a full circumferential weld
but generates a spot weld. Again, the laser is
continuously emitting. 8y forcing the filled capsules to
roll (by mechanical means) whilst exposed to the laser, a
full circumferential weld results. Alternatively, an
optical fibre is used to deliver the IR to the join.
Test Results
PVOH capsules made in the manner described in
Example 1 above were filled with either sugar or
tea leaves_ They were designed to have a cap portion
CA 02414395 2002-12-06
that would dissolve sooner than the body, and thus open
the capsule progressively.
Similarly, a number of conventional gelatine
capsules were also prepared and so filled.
In the Test, a capsule was placed in each Test
Subject's mouth (in the buccal cavity), and the Subject
was asked to note when he/she~became aware of the taste
of the contents - thus, when the capsule "opened" - and
then when the capsule had completely dissolved.
There were two Test Subjects, and each Test was
carried out twelve times (for each filling).
The conventional gelatine'capsules opened in 3-4
minutes, and dissolved completely in 5-8 minutes. The
sugar-filled PVOH capsules of the invention opened in
8-12 minutes, while the tea-filled ones took longer -
19-18 minutes. Complete dissolution took 30-40 minutes
in each case.
