This invention relates to polymeric materials and particularly, although not exclusively, relates to the incorporation of additives into polymeric materials using liquid formulations and apparatus and methods therefor.

It is well-known to use liquid formulations to introduce additives (e.g. colorants, stabilizers, delusterants, anti-static agents, optical brighteners, processing aids etc.) into plastics materials for example in an injection moulder or extruder. For example WO2008/078075 describes an apparatus comprising a reservoir, which may comprise a bag- in-a-box arrangement containing a pre-formulated liquid formulation, which is arranged to deliver the liquid formulation into a reservoir which, in turn, is arranged to deliver the formulation into a pump which is arranged to inject the formulation into melt-processed polymer.

WO2014/122425 describes a bag-in-a-box arrangement comprising a receptacle for liquid formulation which includes an outlet which is connected by a tube to downstream apparatus for delivery of the liquid formulation and apparatus for use therewith. WO2014/207472 describes high pressure injection apparatus for injecting liquid formulations into polymeric materials, for example polyesters, such as in polyester fibre production. The document describes the provision of a tank containing liquid formulation. The tank is arranged to deliver the formulation to a downstream pump, the pressure of the formulation is increased and, subsequently, the formulation is injected into melt-processing apparatus.

Liquid formulations for use as aforesaid are pre-formulated, for example as described in WO2014/122425 and delivered to their point of use in a receptacle which may be a bag-in-a- box pack, a blow-moulded container, a pale or an IBC. An outlet of such receptacle then needs to be connected to a pipe to enable the liquid formulation to be delivered from the receptacle into apparatus which is arranged to introduce the liquid formulation into polymeric material.

A known connector for connecting a receptacle to a pipe may comprise a first connector part attached to the receptacle and a second connector part attached to the pipe. The connector parts may include co-operable first and second valve elements. When the first and second connector parts are engaged, the valve elements are arranged to engage and cooperate and open up a passage through the connector through which fluid may pass. In addition, the first and second connector parts include co-operable first and second elastomeric O-rings arranged to sealingly contact one another when the first and second connector parts are engaged.

Liquid formulations for introduction into polymeric materials may be relatively viscous and may include high amounts of relatively large and/or abrasive particles. Such formulations may include a wide range of chemical constituents which may be harmful to, for example elastomeric materials used in O-rings or other seals, by causing them to soften, swell, dissolve or become "sticky". In view of the aforementioned, it has been found that problems can arise in using known connectors as aforesaid in conjunction with liquid formulations for delivering additives into polymeric materials. For example, in view of the nature of the formulations and the high levels of abrasive particles, the elastomeric seals of the connector may be chemically attacked and/or abraded leading to failure of the connector and consequently "down-time" of the apparatus for introducing the liquid formulation into a polymeric material. Additionally, the arrangement of the first and second parts with their associated valve elements results in the definition of a tortuous/convoluted path for fluid through the connector which leads to a drop in the pressure of fluid as it passes through the connectors. Given that, in many cases, the pressure of fluid upstream of the connector may be relatively low (e.g. at ambient pressure), even a small drop in pressure within the connector may make it more difficult for the fluid to feed downstream apparatus, for example to flood feed a downstream pump. This may lead to downstream inaccuracies in dosing of the fluid into the polymeric material which may lead to the production of defective products.

It is an object of the present invention to address the above problems. It is an object of the present invention, generally, to address problems associated with dosing of liquid formulations into polymeric materials.

According to a first aspect of the invention, there is provided apparatus for delivering a liquid formulation into a polymeric material, the apparatus comprising:

(i) a container for containing a liquid formulation for delivery into a polymeric material, said container including an outlet for the liquid formulation;

(ii) a connector device (A) which is associated with the outlet of the container;

(iii) a connector device (B) which is releasably securable to connector device (A);

(iv) a pipe (B) associated with connector device (B) and being arranged to transport liquid formulation away from said receptacle and towards the polymeric material. Said connector device (A) preferably includes a closure for restricting (preferably preventing) passage of liquid formulation from the container. When the container is in a storage state, said closure suitably prevents liquid formulation from passing out of said container via said outlet.

Said closure is preferably arranged to be opened upon contact with connector device (B) during engagement of connector device (B) and connector device (A), in use, to define an assembly comprising connector device (B) and connector device (A).

Said closure is preferably not screw-threaded. That is, suitably, said closure is not secured, for example releasably secured, in position as part of the connector device (A) by engagement of screw-threaded elements. Said closure is preferably not releasably secured in position as part of connector device (A). For example, it suitably does not include any mechanical interlock (e.g. engagement of screw-threaded elements or engagement of elements arranged to provide a "snap-fit") for releasably securing it in position.

Said closure is preferably a single-use closure. That is, suitably, once the closure has been opened, it cannot readily be manipulated by an operator to act as a closure to prevent passage of liquid from the container.

Said closure preferably comprises a membrane which suitably traverses (and suitably fully closes) an opening (A) in said connector device (A), wherein said opening (A) when open (i.e. when not fully closed by the closure) is arranged to allow passage of liquid formulation from the container and into said connector device (A).

Said membrane suitably comprises a foil. Said membrane is preferably flexible. Said membrane is preferably deformable. Said membrane is preferably substantially inelastic.

Said membrane preferably has a substantially constant thickness across its extent. The thickness may be 1 mm or less or 0.5mm or less.

Said membrane preferably includes a metal-containing layer. It may comprise a laminate which includes a polymeric layer (e.g. a polyalkylene, such as a polyethylene, layer). Preferably, said membrane comprises a laminate comprising a metal - (e.g. aluminium-) containing layer and a polymeric layer.

Said membrane is preferably bonded in position, for example by welding. It may be welded to a surface defined by a plastics material. Said membrane is preferably bonded over and/or around an opening (e.g. opening (A) referred to) in said connector device (A). Said connector device (A) preferably includes a conduit (A). Said connector device (B) preferably includes a conduit (B). Said conduit (A) is preferably arranged to cooperate with (e.g. slideably engage) conduit (B) for transporting liquid formulation away from the container in use. Said conduit (A) is preferably elongate. It preferably has an aspect ratio (defined as its internal length divided by its maximum internal diameter) of at least 1 .5, preferably at least 2.

Said conduit (A) preferably includes an outer end and an inner end, wherein said inner end is positioned closer, in use, to an interior of the container (i.e. which contains liquid formulation in use) compared to the position of the outer end. The inner end is preferably arranged to face into the container in use and the outer end suitably faces away from the container.

Said conduit (A) suitably defines opening (A) (e.g. which is preferably an elongate and/or cylindrical opening) which is suitably closed by said closure, for example said membrane. Said closure is suitably arranged to close said opening (A) at a position which is closer to the inner end than to the outer end of the conduit (A). Said closure (e.g. said membrane) preferably extends transversely, more preferably substantially perpendicularly, to the elongate extent of said conduit (A). In a preferred embodiment, said closure (for example said membrane) is provided at the inner end of conduit (A). Said closure (for example said membrane) preferably makes face to face contact with a face (A) of the conduit (A) at the inner end, suitably so that a seal is defined between the conduit (A) and said closure (for example said membrane) at said inner end. In a preferred embodiment, said membrane is bonded to the face (A) of conduit (A) at said inner end to provide a seal. Said face (A) of conduit (A) is preferably substantially annular. An internal diameter of said face (A) of conduit (A) (e.g. the diameter of the inner circle of the annulus) is preferably greater (e.g. by at least 2mm, at least 4mm or at least 6mm) than a diameter of a wall which defines conduit (A) which extends perpendicular to face (A) and is adjacent thereto. For example, an annular region of said conduit (A) radially inwards of face (A) may taper inwardly in the direction of the outer end of conduit (A) so that an annular chamfer is defined, for example between said face (A) and said wall which defines conduit (A). The chamfer may have a width of at least 2mm or at least 4mm.

Said connector device (A) suitably comprises a first component which comprises said closure (e.g. said membrane) and said conduit (A) as described.

Said connector device (A) may include a second component which cooperates with the first component (and suitably can be disengaged therefrom) wherein said second component is secured, for example permanently secured, to the container. For example, the second component may be a moulded part of the container or may be bonded, for example welded, thereto.

By providing a connector device (A) which is separable from the container, the container can readily be recycled after use without there being a risk that recycled material will be contaminated, for example by material (e.g. metal) which may be used to form the closure. Furthermore, connector devices (A) can be manufactured in large numbers off-site, for example with closures (e.g. membranes) securely welded in position. The connector devices (A) can subsequently be releasably secured to containers. Such a manufacturing process is cost effective and can produce a high quality, consistent seal between the closure and other parts of connector device (A). Connector device (A) can subsequently be releasably secured to a filled container as described herein. This contrasts with prior art process wherein a container is filled with liquid formulation and then a membrane-based closure is welded in position to close the container by an operator at the place of manufacture of the liquid formulation. Not only is this time-consuming, but the welding requires specialised tools and skilled operatives; and is more prone to manufacturing defects and/or premature failure.

In connector device (A), said first and second components are suitably sealingly engaged.. The second component may define a mouth into which the conduit (A) extends with its closure (e.g. membrane) being positioned inside the mouth (and suitably arranged to face into the container in use) and its outer end being positioned outside the mouth (and suitably being arranged to face away from the container in use).

Said connector device (A) may include a third component which cooperates with the first and/or second components and, suitably, said third component can be disengaged from the first and/or second components. Said third component may be a releasably securable component of the connector device (A) which is suitably arranged to releasably secure the first component in position. Said third component may be screw-threaded and may be arranged to screw-threadedly engage the second component.

Said connector device (A) preferably includes no parts capable of reciprocating. It preferably includes no spring-loaded parts. It preferably includes no valve.

Other than said closure, said connector device preferably comprises, more preferably consists essentially of, one or more (preferably only one) type of plastics material.

Connector device (B) preferably includes a body in which conduit (B) is defined. The conduit is preferably elongate. It preferably has an aspect ratio (defined as its internal length divided by its maximum internal diameter) of at least 2, preferably at least 4. An internal wall which defines said conduit (B) preferably has a substantially constant cross-section along its entire extent. The internal wall of conduit (B) preferably has a circular cross- section along its entire extent which cross-section preferably has a constant area along its entire extent. Said internal wall which defines said conduit (B) is preferably smooth and/or uninterrupted. In one embodiment, said internal wall may taper slightly, for example to facilitate the manufacture of connector device (B) by injection moulding.

The body of said connector device (B) preferably has an outer circumferential wall which is preferably arranged to be engaged (e.g. slideably engaged) within a or the conduit (A) of said connector device (A). Said outer wall is preferably tapered. It may include a taper angle of at least 1 ° or at least 2°; and suitably less than 5°. Said outer wall preferably tapers outwardly on moving from a first end which is arranged to be introduced into conduit (A) towards a second end which is suitably axially spaced from said first end. Said pipe (B) may be arranged to be engaged with said connector device (B) at or adjacent its second end.

At its first end, said connector device (B) preferably includes an end wall which faces in a direction which is transverse to said outer circumferential wall. An angle defined between said outer circumferential wall and said end wall is preferably greater than 270°, for example greater than 280° or 290°. Thus, preferably said end wall does not extend perpendicular to the outer circumferential wall. Said end wall preferably includes a point or area which is arranged to initially contact a or the membrane of the closure of connector device (A) in preference to an area of said end wall outside said point or area, when said body of connector device (B) is introduced into conduit (A). Said point or area may be defined by virtue of said end wall being non-planar or extending at an angle greater than 270°, greater than 280° or greater than 290° to the outer circumferential wall of said body of connector device (B). Said end wall of said connector device (B) may define a point and, preferably, the point is arranged to initially contact a or the membrane of the closure of connector device (A), in use, when said body of said connector device (B) is introduced into conduit (A). The second end of the outer wall of connector device (B) may be arranged to be releasably secured to pipe (B), for example by means of an interference fit. To this end, said second end may be non-smooth.

Pipe (B) may have a circular internal cross-section which is substantially constant along its extent. Pipe (B) may have an internal diameter in the range 6mm to 10mm. If the diameter is too small or too large, pipe (B) may detrimentally affect the ability of the apparatus for delivering the liquid formulation to flood feed a pump, arranged downstream of pipe (B), particularly when the liquid formulation is highly viscous and/or includes high levels of solids or other additives. In addition pipe (B) may have a length of less than 1 m, for example less than 0.8m to minimise the pressure drop as a liquid formulation flows within it. In a preferred embodiment, a ratio defined as the internal diameter of pipe (B) (in mm) divided by the length of pipe (B) (in mm) may be in the range 0.0075 to 0.025, preferably in the range 0.01 to 0.02. As described, preferably the body of said connector device (B) has an outer circumferential wall which is suitably arranged to be engaged with conduit (A) of said connector device (A) and conduit (A) suitably defines an opening (A) which may be closed by said closure. Engagement preferably involves insertion of said body of connector device (B) into conduit (A) via outer end of conduit (A). The outer circumferential wall of the body of connector device (B) and conduit (A) are suitably arranged for there to be an interference fit between the two components which seals the components together. Features of the body of said connector device (B) have been described. Preferably, said conduit (A) of connector device (A) is arranged to facilitate an interference fit. To this end, preferably from outer end of conduit (A), conduit (A) preferably tapers inwardly towards a shoulder (A) which is preferably annular. From shoulder (A), conduit (A) preferably tapers outwardly towards the inner end of conduit (A). The closure (e.g. membrane) described is suitably provided at the inner end. The shoulder (A) preferably defines an annular constriction and/or the smallest internal diameter of the conduit (A). Preferably, connector devices (A) and (B) are arranged so that the devices can be sealingly connected together before a or said closure (e.g. membrane) associated with connector device (A) is opened or penetrated to any extent. Thus, in use during engagement of connector devices (A) and (B), a seal between devices (A) and (B) is preferably formed whilst said closure is intact and/or before any liquid formulation can exit the container which is associated with connector device (A).

In an embodiment (A), connector devices (A) and (B) are arranged to cooperate, in use, as follows: (i) body of connector device (B) is inserted into conduit (A) via outer end of conduit

(A);

(ii) the body is urged into conduit (A) until it engages the shoulder (A) and a liquid- tight seal is formed between the connector devices (A) and (B);

(iii) after said seal has been formed, the body is urged further into conduit (A) and during said movement said closure is contacted and opened to define an open path for liquid formulation from the container and into connector device (B), via connector device (A). The apparatus preferably includes a securement device (e.g. a clamp or other locking mechanism) for releasably securing the first and second connector devices (A) and (B) in position. In a second aspect, the invention extends to an assembly comprising the apparatus of the first aspect, wherein connector device (A) is secured at an outlet of the container, connector device (B) is engaged with connector device (A) and pipe (B) is engaged with connector device (B). In an embodiment (B), the assembly may be as described but the closure remains closed and no liquid path is defined from the container into connector device (B). For example, such an arrangement may exist after step (ii) (and prior to step (iii)) described in embodiment (A) of the first aspect. In an embodiment (C), the assembly may be as described and the closure is open to define a liquid path from the container into connector device (B). Such an arrangement may exist after step (iii) described in embodiment (A) of the first aspect.

In the first and second aspects, the container may contain a liquid formulation for delivery into a polymeric material.

In the assembly of the second aspect, a fluid path is suitably defined between the container and a downstream pump. The fluid path preferably has a diameter which is no less than 5mm (preferably no less than 6mm) at any point along its extent. The diameter may be no greater than 20mm at any point along its extent.

Unless otherwise stated, viscosity described herein may be measured using a Brookfield Viscometer at 20 rpm and 23 °C. Said liquid formulation may have a viscosity of at least 5000cP, suitably at leastl OOOOcP, preferably at least 15000cP. The viscosity may be less than 45,000cP, preferably less than 40,000cP, more preferably less than 35,000cP.

Said liquid formulation may include at least 20 wt%, suitably at least 30 wt%, preferably at least 40 wt%, more preferably at least 50 wt%, especially at least 60 wt%, solids. Said solids may comprise particulate material, for example solid pigments and/or dyes. Said liquid formulation may include 85 wt% or less of solids of the type described. Said liquid formulation suitably includes 15 to 70 wt%, preferably 15 to 50 wt% of liquid. Said solids are suitably provided as a dispersion in a liquid which is suitably a vehicle. Thus, the solids may be generally insoluble in the vehicle. The ability to use highly loaded formulations (and consequently relatively low vehicle levels) may be advantageous in minimizing any detrimental effect associated with incorporation of vehicle into the polymeric material. Said solids may be arranged to adjust a property of a polymeric material into which they may be delivered by the apparatus. Said solids may comprise any material that it is desired to introduce into a polymeric material and may be selected from colourants, UV filters, oxygen absorbers, antimicrobial agents, acetaldehyde scavengers, reheat additives, antioxidants, light stabilizers, optical brighteners, processing stabilizers and flame retardants. Colourants may comprise pigments or dyes.

Said solids preferably comprise insoluble colourants (i.e. insoluble in the vehicle), for example insoluble pigments or dyes. Said vehicle is suitably a liquid at STP. Said liquid formulation is preferably a liquid at

STP. Said vehicle preferably has a boiling point (at atmospheric pressure of 760mmHg) of greater than 300°C, preferably greater than 350°C, more preferably greater than 500 °C. The boiling point may be less than 1 150°C or less than 1000°C. The melting point of the vehicle may be less than 0°C or less than -10°C.

Said vehicle is preferably a liquid vehicle. Illustrative liquid vehicles include but are not limited to: mineral oils, C9-C22 fatty acid esters, ethoxylated C9-C22 fatty acid esters, ethoxylated alcohols and plasticizers. Plasticizers may for example be sebacates and azelates, such as dibutyl sebacate, esters such as benzyl benzoate, adipates such as dioctyladipate, citrates such as triethyl citrate, epoxies, phosphate esters such as 2-ethylhexyl diphenyl phosphate, phthalates such as dioctylphthalate, and secondary plasticisers such as chlorinated paraffins.

The sizes of particles in said liquid formulation may be assessed using optical microscopy. Suitably less than 5%, less than 1 % or less than 0.1 % of the number of particles in the liquid formulation have a maximum particle size of greater than 250 μηι or greater than 150 μηι. At least 10% of the number of particles in the liquid formulation may have a maximum particle size greater than 10 μηι, or greater than 20 μηι or greater than 30 μηι or greater than 40 μηι.

The liquid formulation may include particles having a 5 μηι or greater median particle diameter. The median particle diameter may be 100 μηι or less. As used herein, a d50particle size is the median diameter, where 50% of the volume is composed of particles larger than the stated d50, and 50% of the volume is composed of particles smaller than the stated d50value. As used herein, the median particle size is the same as the d50particle size. In the aforementioned the particle sizes and/or median diameter may be assessed by laser diffraction, for example using a Horiba LA950 Laser Particle Size Analyzer. The apparatus may be advantageously used with liquid formulations which include relatively large and/or relatively abrasive additives. For example, the liquid formulation may include a laminar or plate-like material, for example a laminar or plate-like pigment. The additive may be an effect material selected to provide a pearly or nacreous lustre or a granite, marble, holographic or glitter-like effect. The additive may comprise a metal oxide. The additive may be selected from metal oxide coated mica pigments or metal flake pigments (e.g. selected from aluminium flake pigments, iron flake, stainless steel flake, gold bronze pigments and zinc pigments).

In a third aspect of the invention, there is provided an assembly comprising:

(i) a container as described in the first or second aspects which contains a liquid formulation as described for delivery into a polymeric material, said container including an outlet for the liquid formulation; (ii) a connector device (A) as described in the first or second aspects, wherein connector device (A) is secured at the outlet of the container.

The assembly of the third aspect is preferably arranged to cooperate with connector device (B) to define the assembly of the second aspect.

In a fourth aspect, there is provided connector device (A) per se. Said device (A) may be as described in any statement herein.

In a fifth aspect, there is provided connector device (B) per se. Said device (B) may be as described in any statement herein.

According to a sixth aspect of the invention, there is provided a method of assembling an apparatus for delivering a liquid formulation into a polymeric material, the method comprising: selecting an assembly as described in the third aspect;

selecting a connector device (B) as described in the first aspect; (iii) sealingly connecting connector devices (A) and (B) as described in said first aspect; iv) after connector devices (A) and (B) have been sealingly engaged, causing a closure (e.g. membrane) as described in the first aspect to become opened and/or penetrated to define an open path for liquid formulation from the container into connector device (B).

According to a seventh aspect of the invention, there is provided a method of injecting a liquid formulation into melted polymeric material, the method comprising:

(i) selecting apparatus according to the first aspect or an assembly according to the second aspect;

(ii) transferring liquid formulation from the container of the apparatus into connector device (B);

(iii) transferring liquid formulation downstream of connector device (B), suitably by means of one or more pumps; and (iv) injecting said liquid formulation into melted polymeric material downstream of connector device (B) and suitably via a pipe (B) as described in the first aspect.

Said polymeric material described herein may be selected from polyesters (especially PET), polycarbonates and polyolefins. Said polymeric material is preferably a polyester, more preferably PET.

Downstream of contact between said liquid formulation and said polymeric material, the mixture may be used to form sheet or fibre; or other articles in extrusion or blow moulding processes.

Any feature of any invention or embodiment described herein may be combined with any other invention described herein mutatis mutandis.

Specific embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a schematic representation of a dosing apparatus for delivering liquid formulation into a polymeric material; Figure 2 is a schematic representation of high pressure injection apparatus for injecting liquid formulations into a polymeric material, for example in polyester fibre production;

Figure 3 is a cross-section showing part of a receptacle which incorporates a neck which is a component of a female connector assembly of a connector device for connecting the receptacle to a downstream pipe;

Figure 4 is a cross-sectional exploded view of parts of the female connector assembly;

Figure 5 is a top perspective view of a threaded cap of the female connector assembly;

Figure 6 is a cross-sectional view which shows the neck and a female connector element assembled thereon and a threaded cap arranged to be engaged therewith;

Figure 7 is a cross-sectional view which shows the assembled female connector element ready to be engaged with a male connector element;

Figure 8 includes a cross-sectional view through the female element (Figure 8(a)), a view with part of the female element magnified (Figure 8(b)), and a bottom end view of the female element (Figure 8(c)).

Figure 9 shows, in perspective, the female connector element and male connection device, prior to engagement;

Figures 10 to 14(a) and (b) show a sequence of steps during engagement of the male connector device and female connector element; and

Figure 14(c) shows how a membrane of the female connector element is arranged after being contacted by the male connection element (the male connector element being omitted in the interests of clarity);

In the figures, the same or similar parts are annotated with the same reference numerals.

Referring to Figure 1 , dosing apparatus 2 includes a receptacle 4 including a liquid formulation which is connected via pipe 6 to an intermediate reservoir 8. A peristaltic pump 14 cooperates with pipe 6 for pumping liquid from the receptacle 4 to the reservoir 8. The reservoir 8 comprises a plastics bag which is arranged to be pressurized by movement of pressure plate 30. At its lower end, it includes an outlet tube 24 which is arranged to deliver liquid to a dosing pump 26, which, in turn, is arranged to deliver a predetermined quantity of liquid into a polymeric material, for example molten polymeric material in an extruder, via pipe 28.

Referring to Figure 2, high pressure injection apparatus 42 includes a receptacle 44 for initially receiving liquid formulation. The receptacle is subjected to ambient temperature and pressure and need not be stirred or otherwise agitated. The receptacle is arranged to deliver the formulation via pipe 46 into a first pump 48 driven by a motor 49. The pump is suitably arranged to work at a pressure up to 120 bar. Downstream of pump 48, a pipe 50 is arranged to deliver formulation from the pump 48 to a gear pump 52, driven by a motor 53.

Downstream of pump 52, a pipe 54 is arranged to deliver formulation to a pneumatically activated injection valve system 56 which controls injection of formulation via pipe 58 into a dynamic mixer and/or a melt stream (not shown) of an extruder.

The receptacles 4, 44 of Figures 1 and 2 suitably include a pre-formulated, homogenous, liquid formulation which is to be delivered into a molten polymeric material. The receptacles and/or apparatus 2, 42 described may incorporate and/or cooperate with a connection assembly for releasably securing the receptacles 4, 44 to downstream pipework. The connection assembly may be used generally for connecting a receptacle containing a liquid formulation for incorporation into a polymeric material to downstream apparatus arranged to deliver and/or inject the liquid formulation into polymeric material.

The connection assembly comprises a female connection device 74 and a male connection device 76, both of which are shown in Figure 7. Further details on devices 74, 76 are described below. As shown in Figure 4, the female connection device 74 includes three parts - a neck 78, a female connection element 80 and a cap 82 which are arranged to be assembled to define device 74 of Figure 7.

Neck 78 is an integral part of the receptacles 4, 44 as shown in Figure 3. It may be injection moulded or blow moulded in a plastics material, for example HDPE, as part of the receptacle 4, 44. Alternatively, it could be made from another material, for example metal, ceramic or glass and fixed to a receptacle. The neck 78 suitably has a standard threaded form. Female connection element 80, shown in Figure 4 (and also shown in side elevation in Figure 9) is arranged to engage and form a leak-free seal on the neck 78, as shown in Figure 6. To this end, element 80 includes an annular stepped collar 83 extending radially outwardly from a conduit 84 which is closed at its lower end by a pierceable membrane 86.

The collar 83 includes a flanged annular band 87 which is arranged to snugly engage an annular seat 88 provided adjacent an outer edge of the neck 78, as shown in Figure 6. The element 80 is arranged to be releasably secured on the neck 88 by positioning the cap 82 (see Figure 6) over the assembly of element 80 and neck 78 shown in Figure 6 and screw- threadedly engaging cap 82 with the neck 88 to define the female connection device 74, shown in Figure 7. Neck 78 and element 80 are arranged to abut and, when secured in position by the cap 82, sealingly engage one another, without there being any need for provision of an elastomeric seal (or the like) between the parts.

Piercable membrane 86 of connection element 80 comprises a circular foil which completely, sealingly closes lower end of conduit 84. The membrane 86 is arranged to be substantially fluid impermeable, thereby to provide a removable fluid tight seal between the fluid in the container 4, 44 and conduit 84.

The membrane 86 may comprise a laminate, for example comprising an aluminium layer and a HDPE layer.

Lower end 90 of connection element 80 includes a radially-inwardly facing annular chamfer 92 (Figure 8b) of width "x" to reduce the surface area available at the lower end 90 for bonding of membrane 86.

Membrane 86 makes face to face contact with annular downwardly facing surface 94 (having a width "y") of the connection element 80 and is welded thereto, for example ultrasonically, by means of a heated press or by induction. Advantageously, this can be done at a place of manufacture of female connector elements 80, which facilitates production of a high quality, reproducible weld. In addition, advantageously, in contrast to prior art arrangements, a skilled operative does not need to weld a membrane 86 in position directly to a receptacle after the receptacle has been filled with liquid formulation.

Referring to Figure 8, female connection element 80 includes an integral region which is arranged to sealingly engage male connection device 76. Internal cylindrical wall 91 of element 80 is not of a constant cross-section between upper end 95 and lower end 90 thereof. More particularly, wall 91 includes an upper region 93 extending from upper end 95 to position represented by dashed line 97. The upper region may be circularly cylindrical, have a constant cross-section along its entire extent and have a first diameter. Alternatively, the upper region may be slightly tapered (e.g. having about a 2° draft angle to facilitate injection moulding). A lower region 99 of wall 91 which extends from lower end 90 up to a waist area 101

(defined in Figure 8 by line 103) is frusto-conical in that it has a slightly larger diameter at its upper end (adjacent waist area 101) compared to at its lower end 90. Diameter "y" (Figure 8(a)) denotes the diameter of region 99 at its upper end which is the smallest diameter of the region 99. Diameter "y" may be about 12.3mm and the maximum diameter of the lower region 99 is about 12.6mm.

Waist area 101 is a short frusto-conical region which provides a smooth transition between the upper region 93 and lower region 99. The arrangement of regions 93, 99 and 101 allows the male connection device 76 to be secured within the female connection element 80 by means of an interference fit, as described below with reference to Figures 10 to 14.

Female connection element 80 includes an indented region 105 (Figure 10) around the outside of its upper end which is arranged to act as a catch to facilitate releasable securement of the male connection device 76 to female connection element 80.

The female connection element 80 may be made by injection moulding or machining from a plastics material, for example polyethylene, which is compatible with the liquid formulations used as described herein.

Cap 82 of female connection device 76 is annular and includes a circular opening 85, allowing female connection element 80 to pass through. The cap is internally screw-threaded and arranged to releasably engage a corresponding shape on neck 88. At its lower end, cap 82 it includes a tear band 1 10 which cooperates with the neck at position 1 12 to provide a tamper evident function. Although the cap 82 and female connection element 80 are shown as separate parts, they could be manufactured as a single part, for example by injection moulding. As shown in Figure 10, the male connection element 76 defines a conduit having a substantially constant circular cross-section along its extent to provide a smooth path for fluid. At its upper end, it includes annular steps 120 arranged to form an interference fit with a hose or the like. Spaced from its upper end, it includes an annular shoulder 122. From shoulder 122 to end 124, the outer wall 126 tapers inwardly slightly so the diameter defined between pair of arrows 127 is greater than the diameter defined between pair of arrows 128.

The tip 130 of element 76 is diagonally cut so that a pointed region 132 is defined.

The diameter of the outer wall 126 adjacent tip 132 is less than the diameter at upper end 95 of wall 91 of the female connection element 80 by a distance of 2p as represented in Figure 10, so the male connection device 76 can readily be inserted into the female connection element 80.

Engagement of connection device 76 in element 80 is as described below with reference to Figures 10 to 14.

Referring to Figure 1 1 , male connection device 76 is inserted in female connection element 80 without interference until tip 132 is fully within lower region 99 as represented in Figure 1 1 . At this stage membrane 86 is fully intact.

Referring to Figure 12, as male connection device 76 is further urged downwardly, waist area 101 of wall 91 is deformed by being flared outwardly. This forms a fluid-tight seal between device 76 and connection element 80. It should be noted that the seal is formed whilst membrane 86 is still fully intact and, consequently, a liquid-containing receptacle which is connected to connection element 80 can be arranged in any orientation (e.g. upright or upside down) during connection with the male connection device 76, without any risk of leakage of liquid from the receptacle.

Referring to Figure 13, as the connection device 76 is further urged into the female connection device 80, the tip 132 contacts and pierces membrane 86. The diagonally cut arrangement of the tip ensures that the membrane 86 is cut at one side first.

Referring to Figure 14, as the male connection element 76 is further urged into the female connector device 80, the membrane 86 is cut around approximately 90% of its circumference. As shown in Figure 14(b), in view of the clearance between device 76 and the welded area of the membrane 86 created by provision of chamfer 92, material of membrane 86 which bridges clearance "A" in Figure 14(c) allows the membrane to hinge inwards. The resultant flap of membrane 86 (shown in Figure 14(c)) is curled slightly by the cutting action of device 76 and is sufficiently stiff to resist folding shut again whilst device 76 is in position.

Advantageously, male connection device 76 is free to swivel within female connection device 80 so that a hose (not shown) engaged with annular steps 120 can be positioned in any desired orientation. During such swivelling, membrane 86 is not further cut or weakened, but remains attached to the lower end 90 of the female connector device 80.

Male connection device 76 may be made from a plastics material or metal. It is not intended to deform during insertion into the female connection device 74 but may be permitted to yield slightly.

When arranged as shown in Figure 14(a), a clamp device (not shown) may be arranged to engage annular shoulder 122 and indent 123 on female connection element 80 and apply a releasable clamping force between the device 80 and connector device 76, to maintain them in position, providing a sealed fluid flow path.

It should be appreciated that the fluid flow path defined by connector device 80 and connector device 76 is substantially smooth and uninterrupted; and it does not include a valve or other significant constriction which could otherwise impede or significantly reduce the pressure of fluid flowing.

The female connection element 80 and male connection device 76 may be disengaged by removal of the clamping force by operation of the clamp device followed by withdrawal of the male connection device 76 from the female connection device 80. A partially emptied receptacle may be removed, for example to change to a different liquid formulation, by orienting the arrangement so the connection assembly comprising device 76 and device 80 is above the level of liquid formulation in the receptacle 4, 44 to prevent leakage. During disengagement, the membrane 86 remains secured to device 80.

Receptacles (e.g. receptacles 4, 44) are suitably delivered from a manufacturer substantially full of liquid formulation for delivery into molten polymeric material. The liquid formulation may be as described herein. It may be relatively viscous, contain high levels of additives (which may be relatively large and/or abrasive) and/or may include components which are relatively corrosive (e.g. to elastomers). It is found that such liquid formulations can readily be transferred from a receptacle via the connection assembly comprising female connection device 74 and make connection device 76 downstream towards molten polymeric material with little constriction by the connection assembly (i.e. with little pressure drop) and with little risk of the connection assembly becoming blocked (e.g. by large particles contained therein) or being deteriorated by chemical attack by any corrosive components of the formulation. Receptacles for use as described may typically hold 1 to 25 litres when they are arranged to be handled and manipulated by a single operator. Alternatively, packs up to 1000 litres may be provided which require mechanical handling. Receptacles incorporating the female connection device 74 of Figure 7 may be delivered to a point of use. In some cases, conduit 84 may be closed by a dust cap (not shown) or the like to prevent dust or other debris collecting in the conduit 84 before use. On arrival at the point of use, the dust cap may be disengaged from the conduit 84 and discarded or it may remain secured to the device 74 by a flexible tag or the like.

The provision of tear band 1 10 as part of connection device 74 provides a taper evident function which should be inspected prior to use. In addition, after removal of the dust cap, the membrane 86 can be inspected for any signs it has been tampered with or become damaged. Then, by virtue of such investigations, the integrity of the liquid formulation can be implicitly assessed prior to use which is important from a quality assurance perspective.

Receptacles described can readily be recycled by simply removing female connector device 80. This contrasts with prior art arrangements wherein a metal-containing membrane for sealing the receptacle is used. In this case, the membrane (which is usually welded in position) must be completely removed to avoid contamination of recycled material and such a step can be time-consuming and/or may be overlooked.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.