[0001] The present invention relates to a flexible container containing a liquid product,
and to a process for making a liquid-filled, flexible container. The flexible container
may be, for example, a pouch or bag, and it is preferably made from a plastic film.
[0002] Flexible pouches which comprise some sort of spout are useful as packaging for various
sorts of products including drinks. In practice the spout may be closed by means of
a screw cap, or a flip-top cap.
[0003] US 5,307,955, issued on May 3
rd 1994, discloses a lightweight bottom delivery package for fluid products which incorporates
a closure comprising a self-sealing valve and a flip-top cap.
[0004] However such a package may leak during packing or transport if too much pressure
is applied to the bag which causes the self-sealing valve to open, and is sufficient
to displace the flip-top cap.
[0005] Closures have been devised which resist externally applied pressure unless the closure
is first manually opened by the user. US 4,445,551, issued on May 1
st 1984, discloses a quick-disconnect coupling and valve assembly which consists of
a single-service coupling and valve assembly and a connector for cooperating therewith.
[0006] However, it would be useful to provide a lightweight, flexible container, which resists
leaking during packing and transportation, and which can be opened and reclosed so
that it is suitable for multiple doses. Examples of products which are usually sold
in packages containing multiple doses include, but are not limited to: dish washing
liquids, fabric softeners, laundry cleaning liquids, shampoo, skin lotions, foodstuffs,
and the like.
[0007] The flexible container according to the present invention contains a liquid product,
wherein the flexible container comprises a closure having an inner end and an outer
end, the closure being fixed through the wall of the flexible container such that
the inner end of the closure lies within the flexible container and is in contact
with the liquid product, and the outer end of the closure lies outside of the flexible
container, wherein the closure has an open position and a closed position, and wherein
the outer end of the closure is connected to a valve.
Summary of the Invention
[0008] According to the present invention the valve is a self-sealing valve which opens
when the closure is in the open position and when pressure is applied to the liquid
product within the flexible container, and which closes when the pressure is released.
[0009] The present invention further relates to a process for making such a flexible container.
Brief Description of Drawings
[0010]
Figure 1a shows cross-section, A-A, of a flexible container with a closure according
to the present invention. The closure is shown in the open position. Figure 1b shows
a top view of the flexible container and closure.
Figure 2a shows cross-section, A-A, of a flexible container with a closure according
to the present invention. The closure is shown in the open position.
Figure 3 shows an assembly view of a flexible container and closure according to the
present invention in perspective.
Figure 4 shows a perspective view of the liquid-filled, flexible container of the
present invention.
Detailed Description of the Invention
[0011] In its simplest embodiment, the closure of the present invention may consist of two
concentric cylinders: an outer female cylinder and an inner male cylinder. The inner
male cylinder has a blind end, and has at least one hole in the curved cylinder wall.
When the outer cylinder of this closure is fixed through the wall of a liquid-filled
container, there is no passage for the liquid to pass through the closure as long
as the inner cylinder is completely enclosed within the outer cylinder. However when
the inner cylinder is displaced axially relative to the outer cylinder, towards the
liquid-filled container, the hole in the inner cylinder wall becomes exposed, and
liquid may pass through the hole and out of the closure by passing along the inner
cylinder. Displacing the inner cylinder back to its original position closes the dispensing
hole and prevents further liquid from leaving the container.
[0012] In an alternative embodiment, a closure as described in WO99/05446, published on
February 4
th 1999, may be used. In this embodiment the female part has an axial bore and a plug
which closes off the bore. A cooperating male part is provided, and the plug and the
male part are provided with cooperating connection devices which connect the plug
with the male part when the male part is inserted into the bore and which maintain
this connection when the male part is inserted further into the bore. The plug is
provided with at least one hooking part which keeps the plug in the bore until the
plug and the male part are connected to each other while the male part is inserted
into the bore.
[0013] The male and female parts of the connecting device may cooperate by means of a simple
push-pull action, or these two components may be connected by means of a screw thread.
These variations are illustrated in Figures 2 and 4 of WO00/66448, published on November
9
th 2000.
[0014] According to the present invention, the connecting device further comprises a self-sealing
valve. A self-sealing valve is typically made from an elastomeric material such as
silicone or thermoplastic elastomer (TPE). The valve has one or more slits cut through
the elastomeric material. For example, the valve may have two mutually orthogonal
slits. The rate at which liquid product is dispensed under pressure from the container
may be controlled by selecting the size and configuration of the slits in the self-sealing
valve.
[0015] Self-sealing valves are commercially available, one example of such valves is sold
under the Trade Name SimpliSqueeze, supplied by Seaquist Closures, of Mukwonago, Wisconsin,
US.
[0016] By "flexible" it is meant herein that the container may be flexibly deformed, but
that it is not resilient in the sense that it recovers its original shape when the
deforming pressure is removed. Preferably flexible containers of the present invention
are formed from plastic film or films which are sealed together at the edge in order
to form a closed container. The container is provided with an opening which is sealed
around the closure. Most preferably the plastic film is made from polyethylene, polypropylene,
polyester or laminate thereof and has a thickness of from 50 to 250 micrometers.
[0017] The liquid which fills the liquid container may be of any type of liquid, including
relatively viscous gels and pastes. The only limitation upon viscosity is that it
should be possible to dispense the liquid under pressure through the self-sealing
valve. Typical examples of suitable liquid products include detergent products, for
example dish washing detergent liquid, and fabric treatment products, for example
fabric softening liquid compositions.
[0018] Figure 1 illustrates a closure comprising a female part (10) which comprises a collar
(12) which is secured within the opening of the flexible container (2). The female
part (10) further comprises an axial bore (14) and a plug (16). The plug (16) is provided
with at least one hooking part (18) which enables the plug (16) to be removably sealed
within the axial bore (14).
[0019] The male part (20) comprises a cylindrical section (22) which fits within the axial
bore (14) of the female part (10) and which can be moved axially therein. The end
(26) of the cylindrical section (22) removably engages with the plug (16). The male
part (20) and the female part (10) are mutually interconnected by means of a screw
thread (28) so that the male part (20) moves axially within the bore (14) of the female
part (10) when the screw thread (28) is engaged, thereby releasing the plug (16) from
the bore (14), and moves axially in the opposite direction when the screw thread (28)
is disengaged thereby closing bore (14) with the plug (16). The open position is illustrated
by Figure 1; the closed position is illustrated by Figure 2.
[0020] The male part (20) comprises an axial bore (24). The axial bore (24) houses a self-sealing
valve (30).
[0021] A cap (40) covers the closure assembly. The cap (40) may be clipped onto the male
part (20) to facilitate the opening and closing of the closure.
[0022] The resulting assembly provides a one-way valve closure wherein the self-sealing
valve (30) does not permit air to be vented back into the flexible container (2).
Furthermore the closure has a closed position (Figure 2) which is the position in
which the plug (16) is engaged within the bore (14). In the closed position no liquid
can be dispensed from the flexible container (2). The closed position prevents leakage
or accidental dispensing during transport and during storage. The closure has an open
position (Figure 1) which is the position in which the plug (16) is disengaged from
the bore (14). In the open position no liquid is discharged until the liquid pressure
exceeds the threshold pressure of the self-sealing valve (30). When the threshold
pressure is exceeded, the self-sealing valve (30) opens and liquid is dispensed from
the container (2) until the applied pressure is released and the self-sealing valve
(30) recloses.
[0023] Preferably, the liquid within the flexible container (2) is free, or at least substantially
free of any gas, for example the liquid is free, or at least substantially free of
any air.
[0024] Figure 3 shows an assembly view of a flexible container and closure according to
the present invention in perspective.
[0025] Figure 4 shows a perspective view of the liquid-filled, flexible container of the
present invention, incorporating the closure described in detail above. The container
shown in Figure 4 is self standing, wherein the closure is positioned at the top of
the flexible container (2) when the container is self-standing on the base (3).
[0026] In one aspect of the present invention, the liquid-filled flexible container is formed
and filled by the following process steps:
(i) forming a closed flexible container (2) from a film material and fixing a female
part (10) of a closure through the wall of the flexible container (2);
(ii) filling the flexible container (2) with a liquid product by injecting the liquid
product into the container (2) through the female part (10) of the closure;
(iii) sealing the flexible container (2) by closing the female part (10) of the closure,
preferably by means of a releasably fitted plug (16); and
(iv) inserting a male part (20) of a closure into the female part (10) so that the
female and male parts (10, 20) form a closure having an open and a closed position,
wherein the male part (20) of the closure comprises a self-sealing valve (30) which
opens when the closure is in the open position and when pressure is applied to the
liquid product within the flexible container (2), and which closes when the pressure
is released.
[0027] Preferably the self-sealing valve (30) is integrally molded into the male part (20)
of the closure. More preferably the self-sealing valve (30) is molded into the male
part (20) of the closure by means of a co-injection process.
[0028] In one particular aspect of the process, the female part (10) of the closure is sealed
by means of a releasably fitted plug (16) such as is described in WO00/66448. This
process facilitates the filling of the flexible bag with the exclusion of essentially
any gas, in particular with the exclusion of essentially any air.
[0029] In a particularly preferred embodiment of the process the male and female parts of
the closure are fitted together by means of a screw thread (28), and wherein the closure
is opened by rotating the male part (20) relative to the female part (10), and wherein
the closure is closed by counter-rotating the male part (20) relative to the female
part (10).
[0030] The advantages of the closure of the present invention include the avoidance of leaking
or accidental discharge which may occur when a self-sealing valve is used as the only
closing means, or even when a self-sealing valve is used in combination with a flip-top
cap. Further, since the closure is between the fluid and the valve, it eliminates
concerns about long term product compatibility with the valve material since product
contact with the valve only occurs at point of use.
[0031] A further advantage is that liquid-filled, flexible container which is made by the
process described above may be made such that the liquid is substantially free of
gas. The closure described avoids the ingress of any gas, such as air, into the liquid-filled
container during normal use.
[0032] Furthermore the self-sealing valve avoids or minimizes dripping of liquid during
use, and consequently the closure of the invention is mess-free.
[0033] The flexible container is light-weight and cheap to manufacture and transport.
[0034] A further advantage is that the present invention does not have any removable part,
such as a screw cap, that consumer may lose after opening the package.
1. Flexible container containing a liquid product, wherein the flexible container (2)
comprises a closure having an inner end and an outer end, the closure being fixed
through the wall of the flexible container (2) such that the inner end of the closure
lies within the flexible container (2) and is in contact with the liquid product,
and the outer end of the closure lies outside of the flexible container (2), wherein
the closure has an open position and a closed position, and wherein the outer end
of the closure is connected to a valve, characterized in that the valve is a self-sealing valve (30) which opens when the closure is in the open
position and when pressure is applied to the liquid product within the flexible container
(2), and which closes when the pressure is released.
2. Flexible container according to claim 1, wherein the container is filled with the
liquid product and is essentially free of any gas.
3. Flexible container according to claim 1, wherein the closure comprises male (20) and
female (10) parts which are fitted together by means of a screw thread (28), and wherein
the closure is opened by rotating the male part (20) relative to the female part (10),
and wherein the closure is closed by counter-rotating the male part (20) relative
to the female part (10).
4. Flexible container according to any of claims 1 to 3, wherein the container comprises
a base (3), so that the liquid-filled, flexible container (2) is self standing upon
the base (3), wherein the closure is positioned at the top of the flexible container
when the container (2) is self-standing on the base (3).
5. Flexible container according to claim 1, wherein the closure in the closed position
seals the flexible container (2) and prevents discharge of the liquid product.
6. A process of making a liquid-filled, flexible container by:
(i) forming a closed flexible container (2) from a film material and fixing a female
part (10) of a closure through the wall of the flexible container (2);
(ii) filling the flexible container (2) with a liquid product by injecting the liquid
product into the flexible container (2) through the female part (10) of the closure;
(iii) sealing the flexible container by closing the female part (10) of the closure;
and
(iv) inserting a male part (20) of a closure into the female part (10) so that the
male (20) and female (10) parts form a closure having an open and a closed position,
characterized in that the male part (20) of the closure comprises a self-sealing valve (30) which opens
when the closure is in the open position and when pressure is applied to the liquid
product within the flexible container (2), and which closes when the pressure is released.
7. The process according to claim 6, wherein the self-sealing valve (30) is integrally
molded into the male part (20) of the closure.
8. A process according to claim 7, wherein the self-sealing valve (30) is molded into
the male part (20) of the closure by means of a co-injection process.
9. A process according to claim 6, wherein step (iii), the female part (10) of the closure
is sealed by means of a releasably fitted plug (16).
10. A process according to claim 6, wherein the male (20) and female (10) parts of the
closure are fitted together by means of a screw thread (28), and wherein the closure
is opened by rotating the male part (20) relative to the female part (10), and wherein
the closure is closed by counter-rotating the male part (20) relative to the female
part (10).