GB2099391A - Package of liquid components - Google Patents

Abstract

A package of liquid components which are to remain separate until mixed for use, comprises a plurality of pouches (51,52,53) each having a compartment (54,55,56) containing a liquid component and each, other than an outer pouch (51), being disposed within the compartment of another pouch, and a colour indicator in at least one of the compartments which when mixed with at least one of the components in another compartment effects a colour change to thereby provide visual indication of an internal leak between compartments before the package is opened. The outer pouch (51) is made of a polyurethane film and contains a buffer solution. The intermediate and inner pouches (52,53) are made of a polyethylene/ethylene vinyl acetate copolymer film and contain a wetting agent with the colour indicator and hypochlorite solution, respectively. <IMAGE>

Description

SPECIFICATION Package for liquid components This invention relates to a package for liquid components, and is particularly intended for use with the sterilizing system described in British patent application No. 7924300 (publication No. 2025229A) and its divisional application No. 8133545 (publication No.

2084022A).

In these prior application there is described the use of a sterilizing solution for metal medical articles, which solution is contained in a storage container comprising a compartmented package of preferably three compartments, one of which contains an aqueous solution of sodium hypochlorite, another of which contains an aqueous solution of a wetting agent or surfactant, preferably dimethyl lauryl amine oxide, and the third of which contains an aqueous solution of a buffer, preferably dipotassium phosphate together with monopotassium phosphate. In addition, one of the compartments, not that containing the hypochlorite, contains a colour indicator for indicating leakage between compartments. When the package is opened and the contents added to water the various components contained in the respective compartments mix together to form the sterilizing solution.

The nature of the sterilizing solution is more fully described in the abovementioned application No.

7924300.

As described in the abovementioned publication No. 2025229A, articles to be sterilized may be first treated with a conditioning solution prior to treatment with the sterilizing solution.

The package for containing the components of the sterilizing solution, as described in the abovementioned publication No. 2025229A, is formed from four sheets of plastic film superimposed one on top of the other and heat sealed together at their edges to form a pouch having three separate components.

The present invention relates to a package for liquid components having a different construction from that described in the abovementioned publication No. 2025229A in that the respect components are each contained one within the other, and do not have a common sealing seam.

The present invention provides a package for liquid components for a mixture of the type in which the liquid components are to remain separate until mixed for use, comprising a plurality of pouches each having a compartment for separately receiving a liquid component, each pouch other than the outer pouch being disposed within the compartment of another pouch, and colour indicator means in at least one of the said compartments which when mixed with at least one of the components in another compartment effects a colour change of at least one of the said components to thereby provide visual indication of an internal leak between compartments before the package is opened, thereby providing a visual integrity check at the time the package is about to be used.

Preferably there is at least one inner pouch and one intermediate pouch in addition to the outer pouch, the inner pouch being disposed within the intermediate pouch and the intermediate pouch being disposed within the outer pouch.

The inner pouch is suitably freely movable within the intermediate pouch or devoid of any connection to the intermediate pouch, and the intermediate pouch is suitably freely movable within the outer pouch or devoid of any connection to the outer pouch.

Preferably one of the compartments contains a chlorine solution, a second compartment contains phosphate, and a third compartment contains a nonionic surfactant, the colour indicating means comprising a colourant, for example chlorophenol red or sodium chromate, added to at least one of the components.

Preferably the outer pouch is made of polyurethane film and the inside pouches are made of a polyethylene/ethylene vinyl acetate copolymer film, in which case a saturated buffer solution is suitably contained in the outer pouch to utilize the characteristics of high strength, good elongation and chemical resistance of the polyurethane film and to minimize the property of water vapour transmissibility thereof.

Suitably a middle pouch contains a wetting agent with a colour indicator, and an inner pouch contains hypchlorite solution so that when the solution in the middle pouch is mixed with any one of the other solutions in the package, colour in the solution changes to thereby indicate internal leakage.

The invention will be further described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of one embodiment of a package according to the invention; and Figure2 is a section taken along the line 2-2 in Figure 1.

Referring to the drawings there is shown a tripouch 50 having three separate pouches, namely an outer pouch 51, a middle pouch 52 and an inner pouch 53. The inner pouch 53 is located inside the middle pouch 52 which is in turn located inside the outer pouch 51. Therefore, three separate compartments 54, 55 and 56 are formed within the tri-pouch 50 and three different liquid solutions are contained therein.

In the embodiment shown each pouch is formed of plastic film heat-sealed at one or more edges.

Laminated films such as shown in Figure 3 of the above-mentioned publication, No. 2025229A may also be used. The pouches 51 52 and 53 are each separately formed with three closed or sealed edges.

The selected solution is poured into the inner compartment 56 of the inner pouch 53 through an unsealed opening, and the pouch 53 is then sealed.

The sealed pouch 53 is then put in the compartment 55 of pouch 52, and a different solution is poured into pouch 52. Pouch 52 is then heat-sealed completely and then is placed in the outer compartment 54 of outer pouch 51. A different solution is then added to pouch 51 and the latter is then heat-sealed.

As described above, the pouches are separately formed and are not connected to one another so that inner pouch 53 floats in the intermediate pouch 52 and the latter in turn floats in the outer pouch 51.

Thus each pouch is separately sealed to obtain the desired strength without being affected by the other pouches.

The outer pouch is made of a strong plastic film to protect against breakage or rupture. Also, as indicated, since the outer pouch is not attached to the inner pouches, the selection of the material for the outer and inner pouches can be made independently of any properties which may have an effect on their being joined together. Preferably, the outer pouch 51 is made of polyurethane film which has high strength, good elongation properties, and which has the desired chemical resistance to the liquids contained therein.These advantageous properties outweight the fact that polyurethane has a tendency to transmit water vapour therethrough because this latter is offset by the fact that the liquid in the outer pouch, that is buffer and anti-corrosive agent, is almost a saturated solution and thus does not give up water rapidly, thereby minimizing any such water vapour transmission.

With the outer pouch made of a strong material to provide the necessary integrity during handling and shipping in commerce, the intermediate and inner pouches need not necessarily have such strength, but may be made of a material which serves to isolate the liquid material therein from one another.

Thus the materials for the intermediate and inner pouch may be selected for their barrier properties, that is for the properties which prevent migration therethrough of the liquid surrounding such pouches. By way of example the outer pouch may have a thickness of 0.007 inches (0.018 cm) and the two inner pouches may have a thickness of 0.004 inches (0.010 cm). Also the pouches may be transparent or translucent in order to be able to view their contents.

Accordingly, the middle pouch 52 and the inner pouch 53 are preferably made of polyethylene/ ethylene vinyl acetate copolymer (EVA), which has the desired barrier properties for the liquid contained therein and which also has good sealing properties and high strength. The polyethylene/EVA also has good elongation properties which permit it to absorb the energy of impact. The middle pouch 52 contains the wetting agent with the colour indicator, and the inner pouch 53 contains the hypochlorite solution.

The tri-pouch 50 consists of the three separate pouches, and each independently absorbs impact applied to the outer pouch 51 and thus tends to prevent rupture of the outer pouch. The pouches may be less than completely filled, and evaluation of such a tri-pouch 50 showed that partially filled intermediate and inner pouches 52 and 53 cushioned the impact of a drop test and helped prevent the rupture of the outer pouch 51. When the tri-pouch 50 was tested to failure, the two inner pouches 52 and 53 were frequently stretched, showing that they absorbed some of the shock impact.

When a plurality of tri-pouches 50 are stacked for storage or transportation or when they are roughly handled or inadvertently dropped, such tri-pouches stand up very well and even those at the bottom of the stack are not broken.

If internal leaks develop, the liquid in the intermediate compartment 55 of intermediate pouch 52 changes colour. Also, the contents of the intermediate and outer pouches 52 and 51 neutralize the corrosive sodium hypochlorite in the inner pouch 53.

In the embodiment, the tri-pouch 50 is shown as formed rectangular, and each pouch may be cut at the corners or ends to pour the contents thereof into a container. However, the tri-pouch 50 may be made with the configuration shown in Figure 2 of the abovementioned publication No. 2025229A such that each pouch can be cut simultaneously or one at a time by cutting the pointed ends of the pouches.

The hypochloride, wetting agent or surfactant, and phosphate buffer contained in the compartments 53, 52 and 51 respectively may be suitably as described and claimed in the abovementioned Application No.

7924300, for example the compartment 53 may contain an aqueous solution of 0.02 to 1 grams of sodium hypochlorite, the compartment 52 may contain an aqueous solution of dimethyl lauryl amine oxide (30% active), and the compartment 51 may contain an aqueous solution of 1.4 to 20 grams of dipotassium phosphate and 0.08 to 21 grams of monopotassium phosphate. In addition, the colour indicator, for example chlorophenol red, may be contained in the compartment 52 together with the wetting agent or surfactant.

Claims (12)

1. A package for liquid components for a mixture of the type in which the liquid components are to remain separate until mixed for use, comprising a plurality of pouches each having a compartment for separately receiving a liquid component, each pouch other than the outer pouch being disposed within the compartment of another pouch, and colour indicator means in at least one of the said compartments which when mixed with at least one of the components in another compartment effects a colour change of at least one of the said components to thereby provide visual indication of an internal leak between compartments before the package is opened, thereby providing a visual integrity check at the time the package is about to be used.

2. A package as claimed in claim 1, wherein there is at least one inner pouch and one intermediate pouch in addition to the outer pouch, the inner pouch being disposed within the intermediate pouch and the intermediate pouch being disposed within the outer pouch.

3. A package as claimed in claim 2, wherein the inner pouch is freely movable within the intermediate pouch.

4. A package as claimed in claim 2, wherein the inner pouch is devoid of any connection to the intermediate pouch.

5. A package as claimed in any of claims 2 to 4, wherein the intermediate pouch is freely movable within the outer pouch.

6. A package as claimed in any of claims 2 to 4, wherein the intermediate pouch is devoid of any connection to the outer pouch.

7. A package as claimed in any of claims 2 to 6, wherein one of the compartments contains a chlorine solution, a second compartment contains phosphate, and a third component contains a nonionic surfactant, the said colour indicator means comprising a colourant added to at least one of the said components.

8. A package as claimed in claim 7, wherein the said colour indicator is chlorophenol red or sodium chromate.

9. A package as claimed in any of claims 1 to 8, wherein the outer pouch is made of a polyurethane film and the inside pouches are made of a polyethylene/ethylene vinyl acetate copolymer film.

10. A package as claimed in claim 9, wherein a saturated buffer solution is contained in the outer pouch to utilize the characteristics of high strength, good elongation and chemical resistance of the polyurethane film and to minimize the property of water vapour transmissibility thereof.

11. A package as claimed in any of claims 1 to 10, wherein a middle pouch contains a wetting agent with a colour indicator, and an inner pouch contains hypochlorite solution so that when the solution in the middle pouch is mixed with any of the other solutions in the package, colour in the solution changes to thereby indicate internal leakage.

12. A package according to claim 1, substantially as herein described with reference to, and as shown in, the accompanying drawings.