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Title:
COLLAPSIBLE CONTAINER AND NOZZLE ASSEMBLY FOR USE THEREIN
Document Type and Number:
WIPO Patent Application WO/1990/001450
Kind Code:
A1
Abstract:
In one aspect there is described a flexible collapsible moulded preferably seamless tubular container (10) for fluid materials e.g. adhesives and sealants, having a screw threaded neck (13) for receiving a screw-threaded cap or nozzle. At the base of the neck a gripping member is provided, e.g. in the form of an integrally moulded platform or collar (11) with opposite parallel flats (12) which enable the container to be gripped and held during tightening of the cap or nozzle without substantial collapse or twisting of the container thus enabling the cap or nozzle to be done up much more tightly than hitherto to prevent leakages. In a second aspect a novel nozzle assembly is provided in which both the nozzle (15) and the inside of the cap (22) are provided with a complementary stepped frusto-conical configuration which provides at least one and preferably a plurality of annular seals spaced along the length of the nozzle and the cap thereby to prevent leakage of adhesive or sealant around the cap.

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Inventors:
WILKINSON RONALD WILLIAM (GB)
Application Number:
PCT/GB1988/000657
Publication Date:
February 22, 1990
Filing Date:
August 09, 1988
Export Citation:
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Assignee:
PERMABOND ADHESIVES (GB)
International Classes:
B65D1/02; B65D35/02; B65D35/38; B65D47/10; B65D47/12; B65D47/36; (IPC1-7): B65D35/38; B65D35/08
Foreign References:
GB1267887A1972-03-22
FR2508008A11982-12-24
FR2146959A11973-03-09
FR1081275A1954-12-17
US3784040A1974-01-08
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Claims:
CLAIMS
1. A substantially leakproof nozzle assembly for dispensing fluids from flexible and collapsible packaging containers comprising a nozzle member having an integrally formed frustoconical nozzle having at its proximal end a downwardly dependent internally screwthreaded skirt for threadedly engaging the nozzle assembly on the correspondingly threaded neck of the container, and an external screw thread formed in the base of the nozzle adjacent the skirt for the attachment of a nozzle cap, and a frustoconically bored nozzle cap having at its basal end an internal screw thread for attachment of the cap to the nozzle, wherein both the nozzle and the cap have a complementarily . shaped stepped frustoconical configuration provi¬ ding on the external surface of the nozzle at least one annular shoulder or step and on the internal surface of the cap at least one complementary annular shoulder or step, which complementary shoulder or step portion or portions sealingly engage one against the other when the cap is threaded onto the nozzle, thereby to provide at least one annular seal between the nozzle and cap intermediate the proximal and distal ends of the nozzle.
2. A nozzle assembly according to claim 1, wherein the nozzle and the cap have a plurality of such stepped or shoulder portions providing a plurality of such seals spaced along the length of the nozzle.
3. A nozzle assembly according to claim 1, wherein the nozzle member additionally comprises an integrally formed downwardly dependent sleeve coaxially located inside the skirt and which sleeve, when the nozzle assembly is threaded onto the container, sealingly engages the inside surface of the neck of the container, and wherein an Oring seal is located in the skirt in the annular channel formed between the skirt and the sleeve to form a seal with the upper annular surface of the neck of the container when fitted to the nozzle assembly.
4. A flexible and collapsible packaging container for containing and dispensing a fluid through a nozzle assembly screw threaded onto the neck of the container wherein the nozzle assembly comprises a nozzle member having an integrally formed frustoconical nozzle having at its proximal end a downwardly dependent internally screwthreaded skirt for threadedly engaging the nozzle assembly on the correspondingly threaded neck of the container, and an external screw thread formed in the base of the nozzle adjacent the skirt for the attachment of a nozzle cap, and a frustoconically bored nozzle cap having at its basal end an internal screw thread for attachment of the cap to the nozzle, wherein both the nozzle and the cap have a complementarily shaped stepped frustoconical configuration provi¬ ding on the external surface of the nozzle at least one annular shoulder or step and on the internal surface of the cap at least one complementary annular shoulder or step, which complementary shoulder or step portion or portions sealingly engage one against the other when the cap is threaded onto the nozzle, thereby to provide at least one annular seal between the nozzle and cap intermediate the proximal and distal ends of the nozzle.
5. A container according to claim 4, wherein the nozzle and the cap have a plurality of such stepped or shoulder portions providing a plurality of such seals spaced along the length of the nozzle.
6. A container according to claim 4, wherein the nozzle member additionally comprises an integrally formed downwardly dependent sleeve coaxially located inside the skirt and which sleeve, when the nozzle assembly is threaded onto the container, sealingly engages the inside surface of the neck of the container, and wherein an Oring seal is located in the skirt in the annular channel formed between the skirt and the sleeve to form a seal with the upper annular surface of the neck of the container when fitted to the nozzle assembly.
7. A container according to claim 4, wherein the flexible collapsible packaging container is of a tubular configuration.
8. A container according to claim 7, wherein the flexible collapsible packaging container is a blowmoulded seamless tube enclosed at one end and having said screwthreaded neck at the other.
9. A container according to claim 7, wherein the flexible collapsible packaging container has an integrally formed gripping .member located between the end of the container and the screwthreaded neck to enable the container to be gripped and held without any substantial collapse or twisting of the container during tightening of the nozzle assembly thereon.
10. A container according to claim 9, wherein the gripping member takes the form of an integrally moulded platform or collar at the basal end of the neck, between the neck and the container, said platform or collar having at least two parallel flats formed on opposite sides thereof to enable gripping of the collar.
11. A flexible and collapsible packaging container for containing and dispensing a fluid through a nozzle assembly screw threaded onto the neck of the container, wherein (a) the flexible collapsible packaging container is a blowmoulded seamless tube enclosed at one end and having said screwthreaded neck at the other; (b) the flexible collapsible packaging container has an integrally formed gripping member located between the end of the container and the screwthreaded neck to enable the container to be gripped and held without any substantial collapse or twisting of the container during tightening of the nozzle assembly thereon, the said gripping member taking the form of an integrally moulded platform or collar at the basal end of the neck, between the neck and the container, said platform or collar having at least two parallel flats formed on opposite sides thereof to enable gripping of the collar; and (c) the nozzle assembly comprises a nozzle member having an integrally formed frustoconical nozzle having at its proximal end a downwardly dependent internally screwthreaded skirt for threadedly enga¬ ging the nozzle assembly on the correspondingly threaded neck of the container, and an external screw thread formed in the base of the nozzle adjacent the skirt for the attachment of a nozzle cap, and a frustoconically bored nozzle cap having at its basal • end an internal screw thread for attachment of the cap to the nozzle, wherein both the nozzle and the cap have a complementarily shaped stepped frustoconical configuration provi ding on the external surface of the nozzle at least one annular shoulder or step and on the internal surface of the cap at least one complementary annular shoulder or step, which complementary shoulder or step portion or portions sealingly engage one against the other when the cap is threaded onto the nozzle, thereby to provide at least one annular seal between the nozzle and cap intermediate the proximal and distal ends of the nozzle.
12. A container according to claim 11, wherein the nozzle and the cap have a plurality of such stepped or shoulder portions providing a plurality of such seals spaced along the length of the nozzle.
13. A container according to claim 11, wherein the nozzle member additionally comprises an integrally formed downwardly dependent sleeve coaxially located inside the skirt and which sleeve, when the nozzle assembly is threaded onto the container, sealingly engages the inside surface of the neck of the container, and wherein an Oring seal is located in the skirt in the annular channel formed between the skirt and the sleeve to form a seal with the upper annular surface of the neck of the container when fitted to the nozzle assembly.
14. A container according to claim 11, wherein said fluid is an adhesive or sealant.
15. A flexible and collapsible packaging container for containing and dispensing fluids therefrom, said container comprising a generally tubular body of moulded plastics material enclosed at one end and provided at the other with a screwthreaded neck for threadedly receiving thereon a screw threaded cap or nozzle assembly, wherein the flexible collapsible packaging container has an integrally formed gripping member located between the end of the container and the screwthreaded neck to enable the container to be gripped and held without any substantial collapse or twisting of the container during tightening of the cap or nozzle assembly thereon.
16. A container according to claim 15, wherein the gripping member takes the form of an integrally moulded platform or collar at the basal end of the neck, between the neck and the container, said platform or collar having at least two parallel flats formed on opposite sides thereof to enable gripping of the collar.
17. A container according to claim 15, wherein the flexible collapsible packaging container is a blowmoulded seamless tube enclosed at one end and having said screwthreaded neck at the other.
18. A container according to claim 15, fitted with a two part nozzle assembly comprising a nozzle member having an integrally formed frusto conical nozzle having at its proximal end a downwardly dependent internally screwthreaded skirt for threadedly engaging the nozzle assembly on the correspondingly threaded neck of the container, and an external screw thread formed in the base of the nozzle adjacent the skirt for the attachment of a nozzle cap, and a frustoconically bored nozzle cap having at its basal end an internal screw thread for attachment of the cap to the nozzle.
19. A container according to claim 18, wherein the nozzle member additionally comprises an integrally formed downwardly dependent sleeve coaxially located inside the skirt and which sleeve, when the nozzle assembly is threaded onto the container, sealingly engages the inside surface of the neck of the container, and wherein an Oring seal is located in the skirt in the annular channel formed between the skirt and the sleeve to form a seal with the upper annular surface of the neck of the container when fitted to the nozzle assembly.
20. A flexible and collapsible packaging container for containing and dispensing fluids therefrom, said container comprising a generally tubular body of moulded plastics material enclosed at one end and provided at the other with a screwthreaded neck for threadedly receiving thereon a screw threaded nozzle assembly wherein: (a) the flexible collapsible packaging container is a blowmoulded seamless tube enclosed at one end and having said screwthreaded neck at the other; (b) the flexible collapsible packaging container has an integrally formed gripping member located between the end of the container and the screwthreaded neck to enable the container to be gripped and held without any substantial collapse or twisting of the container during tightening of the nozzle assembly thereon, the said gripping member taking the form of an integrally moulded platform or collar at the basal end of the neck, between the neck and the container, said platform or collar having at least two parallel flats formed on opposite sides thereof to enable gripping of the collar; (c) a nozzle member having an integrally formed frustoconical nozzle having at its proximal end a downwardly dependent internally screw threaded skirt for threadedly engaging the nozzle assembly on the corres¬ pondingly threaded neck of the container, and an external screw thread formed in the base of the nozzle adjacent the skirt for the attachment of a nozzle cap, and a frustoconically bored nozzle cap having at its basal end an internal screw thread for attachment of the cap to the nozzle; and (d) the nozzle member additionally comprises an integrally formed downwardly dependent sleeve coaxially located inside the skirt and which sleeve, when the nozzle assembly is threaded onto the container, sealingly engages the inside surface of the neck of the container, and wherein an Oring seal is located in the skirt in the annular channel formed between the skirt and the sleeve to form a seal with the upper annular surface of the neck of the container when fitted to the nozzle assembly.
21. A container according to claim 15, wherein said fluid is an adhesive or sealant.
Description:
Collapsible container and nozzle assembly for use therein

FIELD OF INVENTION

This invention relates to an improved dispensing nozzle construction for containers particularly flexible tubular containers which can be squeezed or progressively collapsed to eject the contents of the container through the nozzle. More particularly the invention relates to an improved dispensing nozzle construction for flexible tubular containers or cartridges containing an adhesive composition which is to be dispensed through the nozzle by the progressive squeezing or collapse of the container or cartridge.

More particularly still the invention relates to an improved nozzle construction for such containers, the nozzle construction comprising a screw-threaded cap, and in which improved sealing means are provided between the cap and the nozzle to prevent leakage of the contents of the container from the nozzle and around the cap during storage or transportation. In a second aspect the invention relates to flexible containers provided with a screw cap and nozzle and provided with integrally formed gripping means enabling a firm grip to be placed about the container during screwing on the cap or the nozzle without risk of squeezing or twisting the container accidentally to eject all or some of the contents of the container during screwing on the cap or the nozzle, and thus enabling the manufacturer, the filler or the user of the container, as the case may be to screw the cap or nozzle tightly onto the container to prevent leakage of the contents of the container around the cap or nozzle during storage or transportation.

BACKGROUND

A wide variety of flexible packaging containers are known usually but not necessarily of tubular configuration, for containing a wide variety of flowable materials, such as toothpaste, washing-up liquids and detergents, adhesives of various sorts, both one part or two part, silicone and other

sealants both for domestic and industrial purposes and which are designed to be ejected or dispensed from the container either by squeezing, or by the progressive collapse of the containers, as for example, in the case of cartridge type adhesive applicators of the type in which a replaceable

5 cartridge of adhesive or other material is placed in an applicator gun which may be activated, for example, by a trigger operating through a ratchet mechanism to cause the progressive collapse of the container, or the progrssive insertion of a piston therein to cause progressive collapse of the bottom end wall of the container to eject the contents thereof through an

10 appropriate applicator nozzle.

In the majority of cases the flexible packaging container is provided with either a screw-threaded cap which can be screwed onto a complementary threaded neck on the container, or with a screw-threaded nozzle assembly whch can likewise be screwed onto the complementary 5 threaded neck on the container, or with both, i.e. with a screw-threaded nozzle assembly interchangeable with a screw-threaded cap.

THE PROBLEM

20 In the manufacture of such flexible packaging containers two problems arise. The first concerns the nozzle construction and in particular the problem of obtaining an adequate seal between the cap and the nozzle to prevent leakage around the cap both on initial manufature and during subsequent usage. This problem is particularly severe in the cases where the

25 nozzle has a f rusto-conical configuration and is designed to be severed upon initial usage of the container at any of the several different points along the axial length of the nozzle, thereby to provide a nozzle opening of different diameters according to the desired dimensions of the bead or stream of adhesive or sealant to be dispensed from the nozzle, the thicker the bead

30 required, the closer the point at which the nozzle is severed relative to the container. Such nozzle constructions are particularly prone to leakage around the cap both upon initial manufacture, and during subsequent usage as a result, for example, of acϊdental squeezing or collapsing of the flexible packaging container during storage or transportation.

35 The second problem arises from the fact that the flexible packaging container particularly substantially circular section tubular containers cannot be gripped firmly enough, either during initial manufacture or filling,

or during subsequent usage, to permit the cap or nozzle to be screwed tightly onto the container without inadvetant squeezing or twisting of the container and the possible ejection of all or part of the contents during the cap or nozzle fitting process. The fitting of a screw cap or nozzle on thin walled tubular containers of circular construction is a particular problem. Traditionally such containers are gripped at their base whilst the cap or nozzle is screwed on by presenting the neck of the container to a cap or nozzle held by a rotary chuck. This arrangement considerably limits the torque which can be applied to tighten the nozzle or cap owing to the tendancy of the thin- walled container to twist during tightening of the cap or nozzle thereon.

SUMMARY OF INVENTION

In one aspect the present invention provides an improved nozzle and cap configuration which provides an improved seal between the screw- threaded cap and the nozzle, both during initial manufacture and filling, and during subsequent replacement of the cap on the nozzle following initial or subsequent usage of the nozzle to dispense a portion of the contents of the container, the remainder of the contents being retained within the container for subsequent dispensing. According to this aspect, the externally screw- threaded nozzle has a stepped frusto-conical conjunction providing one or more annular shoulders or steps along the length of the nozzle, the cap likewise having a complementary stepped frusto-conical bore providing one or more annular shoulders or step which when the cap is threadably engaged on the nozzle sealingly engage against the correspondingly stepped or shoulder portion on the nozzle to provide at least one annular seal disposed about the nozzle and located at an intermediate distance between the external thread on the nozzle and the distal end. Preferably two or more annular steps are provided at different spacings along the nozzle and correspondingly along the bore of the cap to provide a plurality of annular seals between the nozzle and the cap and spaced from one another along the length of the cap. With such a configuration it has been found that a substantially improved seal is obtained between the cap and the nozzle and which substantially eliminates the problem of leakage around the cap during transportation and storage of the full, or partially full container.

In a second aspect the present invention provides a flexible,

collapsible package container for adhesives, sealants and other viscous fluids having a generally tubular body closed at one end and having an externally screw-threaded neck at the other for receiving either an internally screw- threaded nozzle or an internally screw-threaded cap, wherein the said other end of the container is provided with an integrally formed gripping portion intermediate the neck and the container, and enabling the tubular container to be gripped during screwing or unscrewing of the nozzle or cap on or from the container without any substantial collapse or twisting of the container.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a side of elevation of a flexible collapsible or squeezable container according to the invention and provided with a gripping portion adjacent the neck whereby the container may be gripped firmly during the screwing or unscrewing of a cap or nozzle therein without any substantial collapse or twisting of the flexible container.

Figure 2 shows the gripping portion of the container of Figure 1 in plan view.

Figure 3 shows in elevation a nozzle according to the invention with the cap removed and showing the stepped frusto-conical configuration.

Figure 4 shows a section through the neck and gripping portion of the container of Figure 1, with the nozzle of Figure 3 engaged thereon but still with the nozzle cap removed.

Figure 5 shows a section through the screw-threaded nozzle cap used in conjunction with the nozzle shown in Figure 3 and 4, and showing the internally stepped frusto-conical configuration of the cap corresponding to that of the nozzle.

Figure 6 shows an alternative form of nozzle for use with the container of Figure 1.

DETAILED DESCRIPTION

Referring to Figure 1, this shows a side elevation of a preferred form of collapsible tubular container for use in this invention. This is preferably a blow moulded seamless container 10 closed at one end and having a neck

13 at the other provided with an external screw-thread 14.

The blow moulded container may be formed of any suitable plastics

moulding material preferably low density polyethylene.

Although seamless blow moulded containers are preferred because of the absence of seams and other points of weakness liable to burst during progressive collapse or squeezing of the container to dispense the contents through the nozzle, other seamed tubular containers of a variety of configurations are equally amenable to modification in accordance with the present invention to provide the container with gripping means intermediate the tubular body of the container 10 and the screw-threaded neck 13, to enable a screw-threaded cap (not shown) or a screw-threaded nozzle as shown in Figures 3 to 6 to be screwed tightly thereon without causing any substantial collapse or squeezing or twisting of the container, with consequential ejection of all or part of the contents during fastening or unfastening of the cap or nozzle.

According to the preferred aspects of the invention, the gripping means take the form of an integral collar or platform 11 moulded between the body of the. tubular container 10 and the neck 13, the collar or platform 11 having two parallel flats 12 on opposite sides thereof to enable the collar to be gripped and held firmly either by hand during fastening and unfastening of the cap or nozzle, or by the filling machine during initial fitting of the screw-threaded cap or nozzle. The collar or platform 11 may in fact take a variety of different configurations and be provided with any appropriate polygonal configuration in outline e.g. triangular, square, hexagonal, octagonal etc etc.

Preferably the wall thickness of the moulded platform or collar 11 is greater that the wall thickness of the moulded container.

Not only does the provision of the gripping collar or platform 11 prevent undesired collapsing or squeezing of the container during fitting or removal of the cap or nozzle it also enables the container to be gripped during the fitting of the cap or nozzle thereon at a point immediately adjacent and below the screw theaded neck. This is in marked contrast to existing methods of filling and closing such containers where . conventional methods and machines require the container to be gripped at its lower end, thus presenting considerable problems due to twisting of the container during fitting of the cap and nozzle and and severely limiting the torque which can be applied to the cap or nozzle. The provision of an integrally moulded gripping block adjacent the neck of the container also makes it much easier to grip and hold and otherwise circular section tubular

collapsible container.

The preferably seamless blow-moulded collapsible tubular containers according to this invention have been specifically developed as containers for adhesives and sealants, particularly anaerobic adhesives and sealants, and to prevent leakage of the adhesive or sealant around the neck of the container during storage or transport due to inadvertant squeezing or pressure on the container.

The seamless blow-moulded collapsible tubular containers of this invention are particularly designed for use as replaceable cartridges for use in adhesive or sealant applicator guns and in which the cartridge is progressively collapsed, usually from the bottom upwards, by operating of the gun thereby to dispense the adhesive or sealant from the cartridge through the nozzle. Alternatively, of course, the container can simply be squeezed by hand to dispense the contents. In adhesive or sealant applicator guns such collapsible cartridges are often compressed to as little as one fifth of their original length during ejection of the adhesive. The seamless tubular blow-moulded construction is particularly important in this respect in preventing bursting of the cartridge at the seams.

Referring to Figures 2 to 6, these illustrate two different nozzle assemblies for use with the container of Figures 1 and 2 and each comprising a frusto-conical nozzle member provided with an integrally formed downwardly dependant internally screw-threaded skirt for threading onto the neck of the container, and with an external thread for receiving an Internally threaded nozzle cap. Referring first of all to the nozzle assembly of Figures 3 to 5, this assembly has been designed primarily for use with a container of the type shown in Figures 1 and 2 with a view to providing an essentially leak proof assembly. Current designs of nozzle assemblies for collapsible adhesive and sealant containers and cartridges are disadvantageous in that leakage frequently occurs around the nozzle during storage and transport of the sealed containers, either before of after use, i.e. when the seal usually provided at the distal end of the nozzle has been broken and the nozzle cap re-fitted after an initial quantity of the adhesive or sealant has been dispensed. However the novel nozzle assembly of Figures 3 to 5 may be used with a variety of other types of container where the same or similar problems occur. The nozzle assembly of Figures 3 to 5 therefore represents

a completely independant and novel aspect of the present invention.

According to this novel aspect of the invention, the nozzle assembly consists of two parts, the nozzle member (15) itself shown in Figures 3 to 4 and the nozzle cap (22) shown in Figure 5. The nozzle member (15) is of an integrally moulded plastics material eg. polyethylene. The member comprises a stepped frusto-conical nozzle 19 sealed, or usually sealed, at its distal end, and having an external thread 24 proximate its proximal end to receive the correspondingly internally threaded (23) nozzle cap (22). At its proximal end the nozzle member (15) is provided with integrally moulded internally threaded skirt (17) adapted to be received on the screw-threaded neck (13) of the container (14). External ribs or knurls (18) on the skirt (17) permit the skirt to be firmly gripped during screwing and tightening of the nozzle assembly on the neck of the container. The container is preferably of the type shown in Figures 1 and 2, i.e. provided with the means 11,12 for gripping the container adjacent its neck during fitting of the nozzle assembly but the novel nozzle assembly of Figures 3 to 5 is equally applicable to and usable with a variety of other types of flexible or collapsible container.

According to the invention the nozzle (19) has a characteristic stepped frusto-conical configuration providing at least one, and preferably more than one, annular flat shoulder or sealing surface extending around the nozzle at intervals along its length. Correspondingly the nozzle cap (22) has a complementary frusto-conical stepped bore having an equal number of annular flat shoulders or sealing surfaces extending around the inside of the cap and at a spacing along the length of the cap which exactly equals the spacing of the corresponding shoulders or flat sealing surfaces on the nozzle.

As will be apparent when the nozzle cap is engaged onto the nozzle the mating stepped sealing surfaces on the nozzle and inside the cap will engage and provide at least one, and preferably more that one annular seal around the inside of the cap, thereby to prevent leakage of adhesive or sealant, or other fluid contained in the container, around the cap after the nozzle has been pierced. Moreover the nozzle can be opened by piercing the seal at its distal end eg. with a pin, or by cutting off the sealed distal end of the nozzle. Depending on the diameter of the bead of adhesive or sealant to be dispensed, the frusto-conical nozzle can be severed at different points along its length. Except in the unusual circumstances of the nozzle (19) being severed close to its proximal end, at least one, and prefereably more

that one annular stepped surface will be left to provide an annular seal with the corresponding step on the inside of the nozzle cap.

In order further to improve the seal which is provided between the nozzle assembly and the neck of the container, the nozzle assembly of the invention is preferably also provided with a downwardly dependant inner sleeve (20) axially positioned inside the threaded skirt (17), the inner sleeve (20) having an external diameter at least equal to, but possibly slightly larger that the internal diameter of the neck of the container. As shown in Figure 4 the sleeve (20) is adapted to fit tightly inside the neck of the container to provide an additional seal to prevent the contents of the container from leaking around the screw-threaded skirt. Such leakage is also additionally and preferably prevented by the positioning of an O-ring seal (21) in the annular channel formed inside the skirt (1) and between the skirt (17) and the sleeve (20). As shown in Figure 4, the O-ring seal seats on the upper end of the neck (13) when the nozzle assembly is engaged thereon to provide an additional seal therebetween.

As shown in Figure 4, the nozzle (19) has a generally tapering bore (26) leading from the sleeve (20) to the distal end of the nozzle.

Finally Figure 6 shows a modified but slightly less preferred configuration of the nozzle assembly (16) for use with the container of

Figure 1 and 2. In this case the nozzle (26) has a plain rather than stepped frusto-conical configuration, and the cap (not shown) will likewise have a plain frusto-conical internal bore which mates with the external surface of the nozzle to provide a seal extending along substantially the whole length of the nozzle from the external thread (26) which is temporarily sealed by the piercable diaphragm (27). Other details of the nozzle assembly of Figure 6 i.e. the internally threaded skirt (17) and the inner sleeve (20) are as described with reference to the previous embodiment.

Whilst the details of the invention have been hereinbefore descibed with reference to certain specific embodiments, it will be understood that such embodiments are presented solely by way of illustration or examplification, and not by way of limitation, thus modifications improvements and variations may be made therein by persons skilled in the art without in any way departing from the invention herein described and claimed.