WO2007031786A1

WO2007031786A1 - Applicator, kit, and process

Info

Publication number: WO2007031786A1
Application number: PCT/GB2006/003458
Authority: WO
Inventors: Neil Atkin; Malcolm Tom Mckechnie; James Young
Original assignee: Reckitt Benckiser (Uk) Limited
Priority date: 2005-09-17
Filing date: 2006-09-18
Publication date: 2007-03-22
Also published as: GB0519047D0

Abstract

An applicator for delivering a treatment composition to a surface comprises a friable polymeric solid and a liquid or gel treatment composition contained within the solid such that rubbing the applicator on a surface breaks down the solid and releases the liquid or gel. A process for creating the applicator involves impregnation of the treatment composition into the solid by use of supercritical or superheated fluid. The applicator may be incorporated into a holder to facilitate use. The applicator is particularly useful for, cleaning and stain removal on soft surfaces such as fabrics and carpets.

Description

APPLICATOR, KIT, AND PROCESS

The invention is concerned with an applicator for delivering a liquid to a surface and a process for its manu- facture . In particular it is concerned with a friable polymeric solid containing a liquid or gel treatment composition, such as a cleaning or stain removal liquid, which is rubbed against a surface and releases the liquid or gel as the friable polymeric solid is eroded or crumbles away.

Sponges are known in the art and may be in the form of either closed or open cell solid matrices. Actual sponges are solid matrices formed from the exoskeletons of living sponges, and these have been mimicked by synthetic sponges made from solid polymeric materials. It is known to impregnate such sponges with a clean solution and then to apply the solution to a surface to be cleaned. The cleaning solution or liquid is absorbed into voids in the sponge when applied by the user from a separate source of cleaning solution or liquid, and then is squeezed out of the sponge in use when applied to a surface. This process leads to the liquid often coming into contact with the hands of the user necessitating the use of protective gloves. Cleaning liquid may also be wasted in that it permeates into parts of the sponge which are not subsequently used during the immediate cleaning process. Moreover, the sponge must be squeezed and emptied of the cleaning fluid after use in order to prevent its leakage onto any surfaces where the sponge may be stored subsequently. Furthermore, the sponge requires a separate source of cleaning solution or liquid. In order for such sponges to function the cells making up the matrix of the sponge must be interconnected such that liquids can pass from the outside of the sponge into the cells and then re-pass from the interior cells to the outside when required by the user, initiated by squeezing the sponge to close the cells and eject the cleaning liquid.

US 4,476,251 discloses a polyurethane foam having cleaning and germicidal activities. The foam is prepared by mixing together a pre-polymer reactant and water and adding to the mixture, prior to foam formation, a non- ionic surfactant, a quaternary ammonium compound and a silicone based surfactant. The foam is recommended as a disposable wiping pad to household cleaning applica- tions.

US 3,283,357 discloses and disinfecting cleansing pad, where a disposable pad or sponge incorporates a substantially dry water soluble impregnant consisting of a ger- micidal quaternary ammonium compound and amphoteric surfactants which are activated by moistening the pad or sponge immediately prior to use.

WO98/59026 discloses and cleaning material for cleansing surfaces comprising a closed cell foam matrix including an antimicrobial composition. The foam matrix may be a polyurethane foam and the antimicrobial composition may comprise silver ions in the form of a combination with a support material such as titanium dioxide. The silver halide/titanium dioxide is incorporated into the closed cell foam as a solid. It has now been found that problems of the prior art can be overcome by use of a friable polymeric solid, which has a liquid or gel cleansing composition contained within the friable polymeric solid.

In a first aspect the invention provides an applicator for delivery of a cleansing composition to a surface comprising a friable polymeric solid and a liquid or gel treatment composition characterised in that the liquid or gel treatment composition is contained within the friable polymeric solid whereby rubbing the applicator on a surface leads to breakdown of the friable polymeric solid and release of the liquid or gel treatment composition to the surface.

In use the applicator is rubbed against a surface to which it is desired to deliver a liquid or gel treatment composition. For instance, if the liquid or gel is a cleaning liquid or stain removing liquid, the applicator will be rubbed against the soft surface containing the stain or soil to be removed. As the friable polymeric solid crumbles and breaks away from the body of the applicator, the liquid or gel treatment composition contained within the friable polymeric solid is released onto the surface to be treated. Preferably the applicator is used on soft surfaces such as fabrics, woven or knitted, carpets, rugs, upholstery or furnishing fabrics. Because the closed cells are impermeable to the liquid or gel treatment composition, the liquid or gel does not come into contact with the user where the applicator is held by the user, but is only released where the friable polymeric solid breaks down on contact with the surface. Moreover the small particles of the fri- able polymeric solid which are abraded from the applicator in use may also act to absorb the combined liquid or gel plus stain or soil which has been removed from the surface to be treated, when the system is used for re- moval of stains or soil from surfaces.

It will be appreciated that in some cleaning applications such as carpets, the friable solid needs to be removed after application. A preferred method of removal is by vacuuming with a vacuum cleaner. (Indeed the applicator / friable solid may be incorporated into a vacuum cleaner device / attachment) . The vacuuming is preferably performed after a slight delay to allow the actives in the friable solid to act on any soil.

Another use for the applicator is for instance the delivery of a polish to surfaces such as shoes, or leather. The applicator can be grasped by the user without coming into contact with the polish and the pol- ish can be applied directly and efficiently to where it is needed. Alternatively the applicator may be used to deliver pre-treatment agent onto a stain. For instance a composition comprising a bleach precursor such as tetra-acetyl ethylene diamine may be applied to a stain using the applicator as described above, where the stain is on a piece of fabric which is subsequently washed by hand or in a washing machine with a conventional detergent powder containing a peroxide bleach. This allows targeting of pre-treatment ingredients to specific re- gions of garments to be cleaned, minimising wastage of such ingredient. This also has the advantage that ingredients which are potentially harmful to the user do not come into contact with the skin of the user during the application as they would with a conventional sponge. There is no or little leakage or seepage of the ingredients where the applicator is grasped by the user.

Another use for the applicator is as an emergency, out of the home, stain removal application for fabrics where there may be no easy access to a water supply.

Another use for the applicator is as a general hard sur- face cleaner such as a limescale remover over small localised areas such as kitchen and bathroom fittings e.g. taps, or larger surfaces e.g. shower walls.

In another aspect the applicator may be used to- release a fragrance, insecticide, pesticide or mixture thereof onto a surface, the advantage being that the compound is locked in the friable polymeric solid of the applicator and so is not lost through volatility before it is required on a surface.

The friable polymeric solid is preferably a polymeric foam matrix comprising voids enclosed or partially enclosed by solid friable walls. The polymeric foam matrix may be an open cell foam, where the voids are in fluid connection, or may be a closed cell foam.

By closed cell it is meant that at temperatures from 0° to 40° centigrade and atmospheric pressure, the cells are not permeable to the flow of liquid from one cell to the next, such that if one cell contains liquid or gel, the leakage of that liquid or gel into adjacent cells is negligible. Suitably, the polymeric foam matrix may comprise both open and closed cells. Preferably, the polymeric foam matrix is substantially a closed cell foam matrix.

The polymeric foam matrix is preferably made from a friable polymeric material such as polyurethane, polyester, polyether, melamine or expanded polyethylene. Suitable polymeric foams include polyurethane foam and floral foam as supplied by Trident Foams Ltd UK and expanded polyethylene foam as supplied by Custom Foams UK.

The void diameter in the polymeric foam is suitably 1 nm to 0.5cm, preferably lμm to 0.3cm. The thickness of the polymeric foam matrix between the voids is suitably from lOOnm to 0.5cm, preferably lμm to 0.3cm.

The friable polymeric solid may also suitably be in the form of a single phase friable polymeric solid without voids, such as exemplified by a pencil eraser. A suit- able polymer for this purpose is polyvinyl chloride.

In use, the surface to be treated is rubbed with the applicator, and it is particularly preferred for the friable polymeric solid to be of such a friability that it tends to wear away to a limited extent when being rubbed on the surface. Moreover, the fine mildly abrasive particles formed as the friable polymeric solid crumbles in use also provide the benefit of aiding in removal of soil from the surface by abrasion.

A test for friability is as follows. A cube of the friable polymeric material containing the liquid or gel composition (35mm x 35mm x 35mm) is weighed. The cube is pushed down on to a sandpaper surface (3M™ P60 245 grade) with an applied force of 55Og and wiped over a 15 cm length course for 10 wipes. The cube is reweighed to measure weight loss. The range of suitable friability is¹ from 1% to 50% weight loss.

The friability is to be measured after incorporation of the liquid or gel composition, as this ^' may modify the friability of the polymeric material from its staring friability.

The friability can be adapted for suitability to the specific applications, e.g. higher friability for use on soft materials.

Where the treatment composition is a cleansing or bleaching composition, it is preferably an aqueous liquid or gel cleansing or bleaching composition, by which is meant that the composition comprises from 40 to 98wt% of water, preferably from 50 to 95wt% of water.

Suitably the cleansing composition comprises a surfactant selected ^'from the group consisting of anionic, cationic, zwitterionic, non-ionic, amphoteric surfac- tants and compatible mixtures thereof. The cleansing composition suitably comprises from 0.01 to 40wt% of surfactant, preferably from 0.1 to 20wt%. A bleaching composition may also contain such a surfactant in the amounts indicated above.

Suitably, the cleansing or bleaching composition may comprise from 0.1 to 30wt% of a water-miscible solvent. This may assist in soil or stain removal. Suitable sol- vents include alcohols such as ethanol and isopropyl alcohol, and glycol ether solvents such^' as n- propoxypropanol . By water-miscible solvent it is meant the solvent has a solubility in Water of 2wt% or more.

The bleaching composition contains a bleaching agent such as hydrogen peroxide, preferably in an amount of from 1 to 50wt%, more preferably from 3 to 6wt%.

Other compatible, conventional ingredients may also be incorporated in the cleansing composition, such as acids or alkalis, buffers, builders, sequestrants, chelating agents, gelling agents, fragrance, viscosity modifiers, preservatives and antimicrobials.

In one embodiment of the invention, the applicator is in the form of a block suitable to be grasped in the hand, or preferably shaped to fit the hand. During use the end of the applicator that wears away by rubbing the surface being cleaned, takes the shape of the contours of the surface being cleaned, enabling awkward nooks, crannies and corners to be cleaned with greater facility.

Another aspect of the invention concerns a kit of parts comprising an applicator as detailed above and a holder for the applicator wherein the applicator is removably but firmly held within the holder. The applicator is suitably adapted to be grasped in the hand of the user. A preferred embodiment of this aspect of the invention is where the kit has the appearance and characteristics of a dry-stick deodorant device, whereby the applicator device can be progressively extruded from the opening of the holder by the user using means conventionally employed in dry-stick deodorant devices (pushing up the base or rotating the base to feed the applicator out of the holder) .

The application in use may become coloured at the end applied to a stain. Accordingly the kit may also comprise a cutter to remove the coloured part of the applicator before it is reused.

In another aspect, the invention provides a suitable process for incorporating the liquid or gel treatment composition into the friable polymeric solid comprises the following sequential steps:

i) forming a friable polymeric solid into the shape of the applicator,

ii) placing the friable polymeric solid in a pressure vessel,

iii) impregnating the friable polymeric solid with the liquid or gel treatment composition at elevated temperature and pressure within the pressure vessel, and

iv) removing the friable polymeric solid impregnated with the liquid or gel treatment composition from the pressure vessel.

Alternatively, the step (i) of forming the friable polymeric solid into the shape of the applicator may take place after steps (ii) to (iv) . Thus, the invention also provides a process for forming an activator comprising the steps of:

i) placing a friably polymeric solid in a pressure vessel,

ii) impregnating the friable polymeric solid with a liquid or gel treatment composition at elevated temperature and pressure within the pressure vessel,

iii) removing the friable polymeric solid impregnated with the liquid or gel treated composition from the pressure vessel, and

iv) forming the impregnated friable polymeric solid into the shape of the applicator.

A suitable elevated temperature is, for example, at least 5O⁰C, preferably at least 6O⁰C, more preferably at least 80⁰C. A suitable elevated pressure is, for example, at least 2 bar (20OkPa) , preferably at least 3 bar (30OkPa), more preferably at least 5 bar (50OkPa).

Advantageously the friable polymeric solid is impreg- nated with a liquid or gel treatment composition by use of a supercritical or superheated liquid.

By supercritical fluid is meant a substance at a temperature and pressure above the critical temperature and pressure of the fluid.

A preferred supercritical fluid for use in the process of the invention is carbon dioxide. By superheated fluid, is meant a fluid which is heated to a temperature higher than its boiling point, without boiling, by maintaining it at a pressure higher than at- mospheric pressure. It is preferred to use superheated water/steam in the process of the invention, at a pressure of 3 Bar or more, preferably 10 bar or more.

Without wishing to be bound by any scientific theory, it is thought that the supercritical or superheated fluid leads to increased permeability of the friable solid polymer such that the treatment composition can diffuse through the swollen polymer to become entrained within the polymer itself and/or within any voids in the solid if the solid is a polymeric foam.

The process will be further clarified by the following Examples .

Example 1

A block of Trident III foam, obtained from Trident Foams Ltd, was placed in a pressure vessel immersed in water containing lwt% of sodium lauryl sulphate and 0.7wt% of isopropyl alcohol along with 0.5% of fragrance and other minor ingredients such as a preservative.

The vessel was sealed and heated to 150⁰C at a pressure of 10 bar (1000 kPa) . This was maintained for 3 hours then the system was cooled over 24 hours and excess pressure vented.

The resulting impregnated foam was effective as a friable cleaning stick, releasing a liquid cleansing compo- sition when rubbed against fabric. The stain from the fabric could clearly be seen colouring the abraded particles .

Example 2

A block of Floral (dry) closed-cell polyurethane foam, obtainable from Smithers Oasis UK Ltd, was placed in a pressure vessel immersed in water containing 3wt% of so- dium laurethyl sulphate (anionic surfactant) and 4wt% of hydrogen peroxide along with 0.5% of fragrance.

The vessel was sealed and heated to 125°C at a pressure of 10 bar (1000 kPa) . This was maintained for 30 min- utes then the system was cooled over 24 hours and excess pressure vented.

Example 3

A block of Floral (dry) foam was placed in a pressure vessel immersed in water containing 3wt% of sodium lauryl sulphate and 4wt% of hydrogen peroxide along with 0.5% of fragrance.

The vessel was sealed and heated to 75°C at a pressure of 10 bar (1000 kPa) . This was maintained for 60 minutes then the system was cooled over 24 hours and excess pressure vented.

The resulting impregnated foam was effective as a fri- able cleaning stick, releasing a liquid cleansing composition when rubbed against fabric. The stain from the fabric could clearly be seen colouring the abraded particles .

Example 4

A block of Trident III foam was placed in a pressure vessel immersed in supercritical CO₂ containing 10wt% of Isopar™ V (Exxonmobil Chemicals) .

The vessel was sealed and heated to 50⁰C at a pressure of 250 bar (25000 kPa) . This was maintained for 3 hours then the system was cooled over 24 hours and excess pressure vented.

The resulting impregnated foam was effective as a friable cleaning stick, releasing a liquid cleansing composition when rubbed against a fabric. The stain from the fabric could clearly be seen colouring the abraded par- tides.

Example 5

A block of Trident III foam was placed in a pressure vessel immersed in water containing Cillit Bang multipurpose cleaner, obtained from Reckitt Benckiser N. V. The vessel was sealed and heated to 150⁰C at a pressure of 10 bar (1000 kPa) . This was maintained for 3 hours then the system was cooled over 24 hours and excess pressure vented.

The resulting impregnated foam was effective as a friable cleaning stick, releasing a liquid cleansing composition when rubbed against a hard surface. The stain from the fabric could clearly be seen colouring the abraded particles.

Claims

1. An applicator for delivery of a liquid or gel treat- ment composition to a surface, comprising a friable polymeric solid and a liquid or gel treatment composition, characterised in that the treatment composition is contained within the friable polymeric solid whereby rubbing the applicator on a surface leads to breakdown of the friable polymeric solid and release of the treatment composition to the surface.

2. An applicator according to claim 1, wherein the . friable polymeric solid is a polymeric foam.

3. An applicator according claim 1 or claim 2 wherein the treatment composition is a cleaning or bleaching composition.

4. An applicator according to any preceding claim wherein the friable solid is a closed cell polymer foam.

5. An applicator according to any preceding claim wherein the treatment composition comprises a compound selected from the group consisting of fragrance, insecticide, pesticide or mixtures thereof.

6. An applicator according to any preceding claim wherein the friable solid is in particulate form.

7. An applicator according to claim 6, wherein the particle size of the friable soild is from 0.05 mm to 10mm, more preferanly 1mm to 5mm and most preferably from lmm to 3mm.

8. A kit of parts comprising an applicator as claimed in any preceding claim and a holder for the applicator wherein the applicator is removably but firmly held within the holder.

9. A process for forming an applicator as defined in any one of claims 1 to 7 comprising the steps of:

i) forming a friable polymeric solid into the shape of the applicator,

ii) placing the friable polymeric solid in a pressure vessel,

iii) impregnating the friable polymeric solid with a liquid or gel treatment composition at elevated tempera- ture and pressure within the, and

10. A process for forming an applicator as defined in any one of claims 1 to 7 comprising the steps of:

i) placing a friable polymeric solid in a pressure vessel, ii) impregnating the friable polymeric solid with a liquid or gel treatment composition at elevated temperature and pressure within the pressure vessel,

11. A process according to claim 9 or claim 10 wherein the friable polymeric solid is impregnated with the liquid or gel treatment composition by use of a supercriti- cal or superheated fluid.

12. A process according to claim 11 wherein the supercritical fluid is carbon dioxide.

13. A process according to claim 12 wherein the superheated fluid is water.