GB2272197A - Packaging for multicomponent reactive systems - Google Patents

Abstract

A multicompartment bag for packaging and mixing predetermined quantities of a multi-component reaction mixture comprises a flexible sealed envelope (1), divided into two or more separate compartments A, B, each with its own filling nozzle (7a) (7b), by means of one or more elongate clamping members (6) clamped externally across the width of the package. In order to mix the contents, the external clamping member(s) (6) is simply removed to permit the contents of the two compartments A and B to merge. A corner of the package can then be cut off to dispense the mixed contents. Alternatively one of the nozzles (7a, 7b) may be openable to dispense the contents or a further nozzle provided. A window (not shown) may be provided to view the mixing of the contents. <IMAGE>

Description

PACKAGING FOR MULTICOMPONENT REACTIVE SYSTEMS This invention relates to a multi-compartment packaging for multi-component systems, such as two part sealant and adhesive compositions comprising an uncured resin, e.g. epoxy or polyhydroxyether or other polyol, as a first component, and a curing agent therefore, e.g. a polyhydroxy or polyamino curing agent for epoxy resins, or a polyisocyanate for polyhydroxyethers and other polyols etc. thereby yielding a polyurethane, and which two components have to be mixed by the user shortly before application, often in quite specific relative amounts. More particularly the invention relates to a multi-compartment packaging for relatively large volume multicomponent systems, that is to say multi-component systems e.g. sealants and adhesives, that are used in relatively large quantities, of the order of litres rather than millilitres.

More especially still, this invention relates to a multicompartment packaging for polyurethane sealant compositions of the type used in the electrical industry to fill and seal underground cable junction boxes and the like.

Traditionally, underground cable junction boxes have always been filled with bitumen after formation of the electrical join in the junction box. In more recent years, polyurethane compositions have been used for the same purpose and have largely replaced bitumen as the sealant of choice. Commonly the polyurethane sealant compositions are mixed on site by rather crude and potentially hazardous methods, e.g.

by simply mixing the hydroxy resin component and the polyisocyanate in a bucket or other suitable open vessel, and pouring the mix straight into the junction box from the bucket.

The present invention provides a method prepackaging multicomponent systems, such as polyurethane sealant compositions used in the electrical industry, in a sealed multi-compartment package designed to keep the two (or possible more) components apart until required for use, and which package can then be manipulated to mix those two (or more) components, whilst still in the sealed package, and prior to discharging the mixed system from the package.

According to the invention, the package comprises a flexible envelope of liquid impermeable flexible film sealed around its periphery to provide a completely sealed enclosure. Externally engaged on, or engageable with, the flexible envelope and extending across the full width of the envelope are one or more removable clamping members, which when so engaged serve to clamp the adjacent films of flexible material forming the opposed faces of the envelope into liquid-tight sealing engagement one against the other, thereby dividing the envelope internally into two or more separate but temporary, liquid-tight compartments, those separate but temporary compartments being openable one into the other to provide a single mixing compartment occupying the whole interior volume of the envelope by the removal of said clamping member(s).Each of those separate but temporary compartments is provided with a sealable filler means enabling each of those compartments to be filled with a predetermined quantity of a different one of the components of the multi-component system. Preferably those filler means are provided in the same face of the envelope, each at a point spaced from the periphery of its respective compartment as defined by the sealed edges of the envelope and the externally applied clamping means, and preferably substantially centrally of that compartment, so that both or all the compartments, if more than two, can be filled with their respective components substantially simultaneously from a multi-nozzle filling apparatus whilst the envelope is lying flat on a supporting surface, for example, the surface of a continuous conveyor which conveys a succession of envelopes through a filling station.

Preferably each filling means comprises a nozzle sealingly mounted in an aperture provided in the face of the envelope for that purpose, each nozzle being provided with a stopper preferably so designed that when inserted it cannot subsequently be removed except by destruction of the nozzle or the cap. In that way a totally secure system is provided for the packaging and transportation of multicomponent sealant and adhesive compositions, or indeed multi-component systems of any kind, especially those of relatively large volume, that is to say total capacity of all compartments in the range 1 to 10litres or more.

The individual volume of each compartment will, of course, be determined by the positioning of the removable clamping members on the exterior of the package and which divide the envelope temporarily into its several separate compartments. Indeed it is a further and preferred feature of the invention that the or each clamping member comprises a member that is totally separate from the envelope so that it can be engaged with the envelope at any one of several locations, thereby to vary the relative sizes and capacities of the temporary compartments formed within the envelope by the clamping member.Most conveniently each clamping member comprises a two part slide fastener consisting of an elongated tube of resilient plastics metal material having a longitudinal slit extending the length thereof and an elongate clamping bar of equal length which is slidably and resiliently engageable into that elongated slit with the material of the flexible envelope pinched therebetween.

On-site, the user simply removes the external clamping members from the envelope containing the components of the multi-component, e.g. polyurethane, system in the separate compartments, thus enabling those components freely to mix within the still sealed envelope, a process which can be assisted by simply pummelling, shaking or massaging of the still sealed flexible envelope. When the components are sufficiently mixed, the envelope can be cut open and the ready mixed contents discharged. As an alternative to simply cutting or tearing open the envelope, the envelope can, if desired, be provided with an openable dispensing nozzle, usually but not necessarily separate from one of the filling nozzles.

Also in order to ensure adequate mixing, the envelope itself may be of transparent material, or include a transparent window, so that the user himself can see whether or not the system is adequately mixed prior to discharge, a process considerably assisted if the components of the system are differently coloured.

The invention is further described with reference to the accompanying drawings, in which Figure 1 is a perspective view of a multi-component package according to the invention; Figure 2 is an enlarged medium section through one of the filling nozzles; and Figure 3 is an enlarged section through the clamping member.

Referring to the drawings, the multi-compartment package according to this invention, shown here as a two compartment package, but equally well constructable as a three- or four- compartment package depending on the number of separate components of the multi-component system to be packaged therein, comprises an envelope 1 of liquidimpermeable flexible material sealed around its periphery to provide a totally sealed package. Preferably the flexible envelope is constructed of a multiple plastics laminate, most preferably consisting of a central film 1a of linear high density polythene, thickness 38 microns or thereabouts although that thickness is by means critical, sandwiched between two layers Ib, 1c, of metallised polyester film e.g.

of aluminium foil bonded to a film of polyester. thickness (again not critical) of about 12 microns.

Although the three layers la, Ib, and Ic of the flexible laminated film forming the envelope 1 may be area bonded each to the other, preferably they are merely bonded to each other at the margins so that each ply is able to move relative to the other, preferably lubricated by a lubricant, e.g. ethylene-vinyl-acetate (EVA) copolymer applied between the plies of the laminate.

In constructing the sealed envelope 1, two sheets 3, 4 of the 3ply plastics laminate la, Ib, Ic are superimposed one on the other and the two heat sealed together around the periphery 5 of the envelope.

The total internal volume of the sealed envelope thus formed may be anything from 1 to 10 litres or more according to need.

Extending across the full width of the envelope 1 is a removable clip or clamping member 6 shown in more detail in Figure 3. When in position, this clamping member 3 effectively divides the package into two separate fluid tight compartments A and B, the relative volumes of which can be varied according to the positioning of the clamping member 6.

As shown in more detail in Figure 3, the clamping member 6 comprises a clamping bar 6a over which the two layers 3, 4 of the envelope 1 are folded and crimped between the clamping bar 6a and a spring circlip 6b formed from elongated split tube of resilient plastics or metal material having a longitudinal slit therein to permit the circlip either to be pressed onto, or slid longitudinally into engagement with the underlying clamping bar 6a, thereby securing the folds of the envelope tightly together between the bar and the clip and so as to form a fluid-tight, but temporary seal between the two compartments A and B.

Heat sealed via their respective base flanges 11 into a performed aperture centrally located in each of the compartments A and B are two identical filling nozzles 7a, 7b, each equipped with its own stopper 8a, 8b. As shown in Figure 2, each stopper 8a, 8b is a press fit within its own filling nozzle 7a, 7b. Not only that, but each nozzle 7a, 7b has an internally directed annular retaining rib or shoulder 9a shown only in the cross-section of nozzle 7a, shown in Figure 2, the construction of nozzle 7b being identical.Correspondingly, each stopper 8a, 8b has an externally outwardly directed annular ridge or rib 10a, which, when the stopper is pressed home into the nozzle, snaps into engagement with the retaining rib or shoulder 9a, effectively locking each stopper permanently into its respective nozzle after the components of the two part composition have been charged to their respective components A and B through the nozzles.

As will be apparent, the positioning of the two nozzles 7a, 7b substantially centrally of each of the two compartments A and B, and on the same side or face of the envelope 1, enables both compartments to be filled with their respective components of the two-part composition substantially simultaneously by placing the unfilled envelope, with the clamping member 6 in position, on a suitable supporting surface, e.g.

a conveyor belt, with the open filling nozzles directly upwardly, feeding the envelope, or a succession of envelopes to a filling station having downwardly directed filling nozzles connected via suitable metering and valved shut-off means each to a reservoir of its respective component, simultaneously filling each compartment A and B with a predetermined metered amount of its respective component, and thereafter sealing each nozzle with its respective stopper.

Preferably each filling nozzle is so constructed, in a manner known per se, that after filling and pressing home the stopper, each filling nozzle may then be pressed into a retracted position so as no longer to project substantially above the surface of the package. In that way a substantially flat package is obtained which considerably eases the subsequent storage and transportation.

Although the manner of subsequently mixing and dispensing the contents of the package will be obvious, this procedure involves: 1. removing the removable clamping member or members 6 from the package, thereby permitting the contents of compartments A and B to mix freely in the still sealed but no single compartment envelope; 2. working the sealed package so as to mix the contents thoroughly; 3. cutting or tearing open the sealed envelope, for example, at one of the four corners; and 4. dispensing the mixed contents from the package through that torn or cut opening.

As already indicated, if desired, a separate dispensing valve can be provided, or alternatively one of the two stoppers may, in fact, be removable so that the mixed contents of the package can be discharged through that filling nozzle. Also to ensure uniform mixing a transparent window can be provided in the package so that the contents can be seen as they are mixed.

The above described package has been particularly designed for polyurethane sealant compositions used in the electrical industry. In that case, one or either of the two compartments will be charged with a hydroxy-terminated resin, usually, but not necessarily a blend of castor oil and a polyether- polyol, often containing sand as an inert filler, whilst the other will be charged with a suitable diisocyanate, e.g. toluene diisocyanate, which may or may not also contain a proportion of the inert filler. Since the proportions of resin and isocyanate are predetermined, and since the mixing is carried out in a sealed environment, risk to the user is minimised whilst the properties and performance of the mixed polyurethane composition are maximised.

The above principles may, however, be applied equally well to a wide variety of other multi-component systems, and is therefore not limited to any particular system. Not only that but numerous mechanical modifications, improvements and other changes may be made in the packaging as specifically described above but without departing in any way from the concept of the invention herein described and hereinafter claimed.

Claims (16)

CLAIMS:

1. A multi-compartment packaging system for multi-compartment compositions consisting of two or more reactive components which are mixed immediately prior to use, said packaging comprising a flexible envelope of liquid impermeable flexible film sealed around its periphery to provide a completely sealed enclosure, one or more removable clamping member or members engaged on or engageable with the sealed envelope and extending across the full width of the envelope thereby temporarily dividing the interior of the envelope into two or more fluid-tight compartments, the clamping member or members being removable or releasable to restore open communication between the two or more compartments and so to provide a single, but still sealed, mixing chamber within said envelope, and two or more sealable filling nozzles, one located in each of the said separate but temporary compartments formed within the envelope by said clamping member(s), said sealable filling nozzles permitting the individual reactive components of said multi-component composition to be charged in predetermined quantity each into a separate one of those compartments and following which the end of said nozzle may be sealed to provide a completely sealed flexible package containing the reactive components of the multi-component composition within their respective, separate compartments until such time as the clamping member(s) are removed to permit the contents of the compartments to be mixed within the sealed envelope and prior to discharge of the mixed composition from the envelope.

2. A packaging system according to claim 1, wherein said filling nozzles are located each on the same face of the envelope as the other and each positioned within its respective compartment at a location spaced from the sealed periphery of the compartment as determined by the sealed edges of the envelope and/or the clamping means externally engaging across the width of the envelope.

3. A packaging system according to claim 2, wherein after filling the respective compartments and sealing the filling nozzles, the filling nozzles are retractable into the body of the envelope so that the upper surface of the nozzle lies substantially flush with the surface of the envelope.

4. A packaging system according to claim 1, 2 or 3, wherein each filling nozzle is provided with a stopper and means are provided interactive between each stopper and its respective nozzle to lock the stopper permanently into its respective nozzle after the stopper has been pressed home into its respective nozzle.

5. A packaging system according to any one of claims 1 to 4, wherein the or each clamping member is completely detachable from the envelope and is engageable thereon in a variety of different positions thereby to vary the relative volumes of the compartments defined within the envelope by that clamping means.

6. A packaging system according to claim 5, wherein the clamping member comprises an elongated circlip comprising a tube of resilient material having a length equal to the width of the package and a longitudinal slit extending the length of the tube, and a bar member of equal length resiliently engageable into the slit of the circlip with the material of the flexible package crimped therebetween.

7. A packaging system according to any one of claims 1 to 6, wherein the envelope is constructed of a three ply plastics laminate comprising a central ply of linear high density polythene located between two outer plies of metallised polyester.

8. A packaging system according to any one of claim 1 to 7, wherein the envelope is constructed of a flexible laminated film comprising two or more plies of plastics film bonded one to the other around the periphery of the envelope, but are free from bonding one to the other in the central zone of each ply.

9. A packaging system according to claim 8, wherein the individual plies of the laminated film are coated with a lubricant in said central zone.

10. A packaging system according to any one of claims 1 to 9, wherein the envelope is constructed from, or has a window of transparent flexible film located therein to permit viewing of the contents of the package following removal of the clamping member(s) and during subsequent mixing of the contents of the package.

11. A packaging system according to any one of claims 1 to 10, which has but a single clamping member dividing the envelope temporarily into two compartments for the two components of a two component system.

12. A packaging system according to any one of claims 1 to 11, containing the reactive components of a multi-component reactive system packaged therein each component in a different one of the temporary compartments provided therein by the clamping member(s).

13. A packaging system according to claim 12, wherein said multicomponent reactive system is a two component system.

14. A packaging system according to claim 13, wherein said two component system is a polyurethane system.

15. A packaging system according to claim 14, wherein the first component of the two component system packaged into a first compartment of the packaging system comprises a polyetherpolyol in admixture with sand as a filler and with linseed oil, and the second component comprises a diisocyanate reactive with said linseed oil/polyetherpolyol/sand mixture to provide a dielectric polyurethane filler composition for filling underground and other electrical cable junction boxes.

16. A packaging system according to claim 1, substantially as hereinbefore described with reference to the accompanying drawings.