GB2318778A - Recharging a container for dispensing liquid preparations using a soluble sachet - Google Patents

Abstract

The trigger-type spray unit 16 which is secured to narrow neck portion (12) of container (10) via external screw threads (14), is removed and said container is charged with a quantity of liquid 18, preferably cold water, and a liquid soluble sachet 20 containing a concentrate material 22, either in powder or liquid form, to be dissolved in 18. Said sachet 20, typically of elongate form, is constructed from polyvinyl alcohol (PVA) which dissolves easily in cold water and is dimensioned to fit easily through the narrow neck portion (12) of (10). The PVA film having a film thickness in the range 35-55~, preferably 40c2~, is used to prepare 20. PVA also has a secondary advantage as it will serve as a non-ionic surfactant when in solution and so aid the cleaning characteristics of the prepared liquid solution. The concentrate 22 may include a drying agent to limit the effect of moisture on 20 and its contents prior to its dissolution in 18. When in powder form 22 may be coated with an inert screening material to prevent reaction between 22 and the PVA material of the sachet.

Description

METHOD OF RECHARGING A CONTAINER FOIR A LIOUID SUBSTANCE This invention relates to a method of recharging a container for a liquid substance, especially for cleaning substances or preparations for general domestic or light industrial use.

It has been common practice for many years to buy products such as liquid cleaning substances, for example hard surface cleaners, in bottles having a dispenser thereon in the form of a hand operated trigger spray unit. Such trigger spray units are particularly convenient to use. However, once the container has been emptied of its product, the usual practice is to throw away the container along with its trigger spray unit. As the spray unit is an expensive part of the product, such a practice is wasteful and uneconomic. Therefore it is becoming common to supply refills in the form of new bottles containing the appropriate liquid substance on to which the user fits the previous trigger spray unit Nevertheless, such a practice is only partially economic as the previous bottle is thrown away.

An object of the present invention is to provide a method of recharging a container for a liquid substance which will minimise wastage.

According to one aspect of the invention there is provided a method of recharging a container for a liquid substance having thereon a dispenser for dispensing the liquid substance, the method comprising removing the dispenser from the container to be arged, introducing into the container a quantity of liquid and a liquid soluble sachet of concentrate and either prior to or after replacing the dispenser on the container causing the concentrate from the dissolved sachet to be dispersed or dissolved in the liquid to produce the liquid substance, in which the sachet is formed from polyvinyl alcohol filmy Preferably the liquid comprises water, conveniently cold water direct from the mains supply.

It will be appreciated that the use of the invention allows the dispenser and container to be retained thereby enabling the container to be recharged without wasting either the dispenser or the container.

Preferably, the sachet is dimensioned to fit through an. opening on the container with working clearance and, in that respect, may be of elongate form. Typically, the openings on such containers are only some 2cm in diameter and the maximum lateral dimension of the filled sachet should therefore be not more than about 2cm.

The sachet may contain a concentrate in the form of a powder, for dissolution in the liquid or water, or a liquid, for dilution with the liquid or water.

The method may include utilising a dispenser in the form of a hand operated spray unit having a feed pipe arranged to project downwardly into the container.

According to a second aspect of the invention there is provided a container for liquid having a neck portion on which a removable dispenser is mounted, and a sachet dimensioned to fit through the neck portion of the container after the dispenser has been removed therefrom, the sachet being formed from polyvinyl alcohol film and containing a concentrate which can be dispersed or dissolved in the liquid after the sachet itself has dissolved.

According to a third aspect of the invention, there is provided a sachet containing a concentrate which can be dispersed or dissolved in a liquid following dissolution of the sachet in the liquid, in which the sachet is suitable for passing through the neck of a container containing said liquid and is formed from polyvinyl alcohol film.

It has been found that, among possible film materials, polyvinyl alcohol has utility for the purposes of the present invention in that it can readily be formed into a sachet of the required size and shape; it is soluble in cold water even at temperatures as low as 50C; it is laandleable for a sufficient time to allow the sachet to be placed in the container witbout softening or disintegration; and it is inert to most concentrate materials for which the invention is intended for use. In terms of dissolution in the liquid, preferably water, it is desirabled that dissolution should be complete within about five minutes, preferably from two to five minutes, even with cold water at a temperature of less than 100C and in the relatively low volumes typically encountered for the intended use. It is also desirable that the resulting solution is clear (that is, haze-free) and does not separate on standing.

Polyvinyl alcohol film having a film thickness in the range 35 to 55 micrOns has been found to be suitable, preferably 40s2 microns. Polyvinyl alcohol also has the secondary advantage that, when the liquid substance is a cleaning preparation, the polyvinyl alcohol dissolved therein acts even at the low concentration encountered as a non-ionic surfactant and contributes to the cleaning properties of the liquid substance.

The concentrate material especially when in the form of particles or granules may be coated or encapsulated by an inert screening material to prevent contact between the concentrate material and the sachet, where any such contact would be likely to result in reaction between the concentrate and sachet materials causing either a lessening in the activity of the concentrate material or a reduction in the solubility of the sachet material in the solvent. In another embodiment, a drying agent may be included in the concentrate formulation to control moisture levels and decrease the rate of any reaction between the sachet material and the contents, thereby maintaining the ability of the concentrate to be dispersed in the water or other solvent and assisting its eventual dissolution. Where the concentrate material is a liquid, the pH should preferably be within the medium alkalinity range of 9 to 9.5 or thereabouts.

Typical concentrate formulations for solid concentrates include a builder compound selected from a sodium tripolyphosphate (STPP) or other soluble salts such as sodium nitrilo triacctate, sodium carbonate, sodium bicarbonate or mixtures thereof; a watersoftening agent such as the di-sodium salt of ethylenediarninetetraacetic acid (DSEDTA); a moisture-controlling agent such as anhydrous sodium sulphate; and an active ingredient according to the intended purpose. For example a hard surface cleaner may contain as active ingredient a fatty alcohol ethoxylate, sodium lauryl sulphate or ethoxylated derivative thereof, sodium dodecyl benzene sulphonate or mixtures thereof or other metal salts thereof, while a sanitising hard surface cleaner may contain Ceerimldc BP.

optionally, the formulations may also include thickening agents such as acrylic polymers or celluloses or Xanthan gum-type thickness which may also enhance the cleaning, foam generation or foam stability properties of the composition. Additionally, perfumes may optionally be included and, if present, preferably are highly concentrated and are intimately mixed witb the other ingredients, for example by tumbling in order so as not adversely to affect the flow characteristics of the powder. Silica may also be added to improve the flow characteristics.

For use as window cleaning or degreasing compositions, typical liquid formulations include glycols such as propylene glycol monomethyl ether (PGME) or dipropylene glycol monomethyl ether, optionally together with ethoxylated fatty alcohol, isopropylamine dodecyl benzene sulphonate and/or ethoxylated nonyl phenols, ethoxylated castor oils, d limonene and various ethanolamines as examples of surfactants, and optionally perfume.

Exemplary compositions are as follows, in which all percentages are by weight: 1) Hard surface cleaner (solid) 50-75% S1sPP 5- 15% DSEDTA 10 - 20% anhydrous sodium sulphate 5 - 15% 25 - 100 mole fatty acid ethoxylate 0- 1% perfume 2. Sanitising hard surface clcaners (solid) 50 - 75% STpp 5- 15% DSEDTA 10 - 20% anhydrous sodium sulphate 5-15% Cetrimide BP 3. Window cleaner (liquid) 80-100% PGME 1 - 10% ethoxylated fatty alcohol 1 - 10% isopropykninc dodecyl benzae sulphanax 0- 1% perfume A method of recharging a container in accordance with the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is an elevation of an empty container having a dispenser in the form of a trigger spray unit, Figure 2 is an elevation of the container of Figure 1 with the spray unit removed, the container being.pattially filled with water, Figure 3 is a view similar to Figure 2 showing a sachet being inserted into the container, Figure 4 shows a sachet of Figure 3 immersed in the water within the container, Figure 5 shows the container following the re-fitting of the spray unit, and Figure 6 shows the container and spray unit after the sachet and contents therein have been dissolved in the water.

In Figure 1 a container 10 has a narrow neck portion 12 at its upper end formed with external screw threads 14 (Figure 2) for mounting a trigger spray unit 16. The container 10 and spray unit 16 are of known kind, the latter having the usual feed pipe 17 projecting downwardly into the container. Typically, the capacity of the container 10 may range from around half a litre to around one litre and normally contains product such as an all purpose hard surface cleaner, a sanitising hard surface cleaner, oven cleaner, glassfwindow cleaner, bathroomitoiler cleaner or other formulation which is typically water based and which can be sprayed by operating the trigger spray unit 16. Figure 1 shows the container 10 after all the contents have been dispensed therefrom In order to recharge the container in accordance with the invention, the trigger spray unit 16 is unscrewed from the container 10 and the container 10 Is partially filled with water 18 as shown in Figure 2. A sachet 20 made from polyvinyl alcohol film of thickness 40 and formed by a casting technique contains a concentrate 22 which, when diluted with water, will provide the required liquid product in the container 10. Typically, the contents 22 of the sachct 20 will be in the form of a powder but may take the form of a liquid. It will be noted that the sachet 20 is ideally elongate and sufficiently narrow to pass through the neck 12 with working clearance making it easy for a user to introduce the sachet 20 into the container 10 as shown in Figure 3. Alternatively the sachet 20 may be folded or rolled to fit through the neck 12. The sachet 20 drops to the bottom of the container 10 as shown in Figure 4 so as to be immersed in the water 18. The trigger spray unit 16 is then screwed back on to the container 10 as shown in Figure 5 and the container is shaken by the user as indicated by arrow A to dissolve the sachet 20 and the contents 22 in the waler 18. The dissolved contents produce the required product indicated at 24 in Figure 6 which is then ready for dispensing as required by using the trigger spray unit 16.

When the product 24 has been exhausted, any residue can be washed from the container 10 before recharging. Also, to help dissolve the sachet 20 and contents 22 more quickly, wann water 18 may be introduced into the container at the Figure 2 stage.

The invention is advantageous in that the container 10 and trigger spray unit 16 are retained for repeated use rather than being thrown away thercfore leading to a reduction of waste and increased economy.

Claims (13)

1. A method of recharging a container for a liquid substance having thereon a dispenser for dispensing the liquid substance, the method comprising removing the dispenser from the container to be recharged, introducing into the container a quantity of liquid and a liquid soluble sachet of concentrate and either prior to or after replacing the dispenser on the container causing the concentrate from the dissolved sachet to be dispersed or dissolved in the liquid to produce the liquid substance, in which the sachet is formed from polyvinyl alcohol film.

2. A method according to claim 1, in which the liquid comprises water.

3. A method according to claim 1 or claim 2, in which the sachet is dimensioned to fit through an opening on the container with working clearance and is preferably of elongate form.

4. A method according to claim 3, in which the maximum lateral dimension of the filled sachet is not more than about 2cm.

5. A method according to any preceding claim, in which the sachet contains a concentrate in the form of a powder.

6. A method according to any preceding claim, in which the method includes utilising a dispenser in the form of a hand operated spray unit having a feed pipe arranged to project downwardly into the container.

7. A container for liquid having a neck portion on which a removable dispenser is mounted, and a sachet dimensioned to fit through the neck portion of the container after the dispenser has been removed therefrom, the sachet being formed from polyvinyl alcohol film and containing a concentrate which can be dispersed or dissolved in the liquid after the sachet itself has dissolved.

8. A sachet containing a concentrate which can be dispersed or dissolved in a liquid following dissolution of the sachet in the liquid, in which the sachet is suitable for passing through the neck of a container containing said liquid and is formed from polyvinyl alcohol film.

9. A sachet according to claim 8, in which the polyvinyl alcohol film has a film thickness in the range 35 to 55 microns.

10. A sachet according to claim 8 or claim 9, in which the concentrate material is in the form of particles or granules coated or encapsulated by an inert screening material to prevent contact between the concentrate material and the sachet.

11. A sachet according to any of claims 8 to 10, in which a drying agent is included in the concentrate formulation to control moisture levels and decrease the rate of any reaction between the sachet material and the contents.

12. A sachet according to claim 8 or claim 9, in which the concentrate material is a liquid, the pH of which is within the medium alkalinity range of 9 to 9.5 or thereabouts.

13. A method of recharging a container substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.