AU775938B2 - Sanitising composition and method - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT 0 a 0 0**0 *0 0 seop .000 *0 0 *0*0 .00.

~0 0. 0 0@ 0O *0 Applicant: CLEARWATER CONCEPTS PTY LTD A.C.N. 083 414 537 Invention Title: SANITISING COMPOSITION AND METHOD The following statement is a full description of this invention, including the best method of performing it known to

US:

2 FIELD OF THE INVENTION The present invention relates to a solid sanitising composition, to a sanitising solution prepared from the composition, and to a method of sanitising which utilises the sanitising solution.

SUMMARY OF THE INVENTION In a first aspect, the present invention provides a solid sanitising composition including, as active components, an oxidising agent, a water softening agent, a halide salt and a surfactant, the composition being arranged such that a solution formed by dissolving the composition in water has a pH in the range 6-8.

In a second aspect, the present invention provides a solid sanitising composition including, as active components: 15-60% by weight oxidising agent, 15-70% by weight water softening agent, 1-20% by weight halide salt, and 0.05-3% by weight surfactant; the composition being arranged such that a solution formed by 20 dissolving the composition in water has a pH in the range 6-8.

In a third aspect, the present invention provides a sanitising solution formed by dissolving a solid sanitising •composition according to the first or second aspects of the :present invention in water.

25 In a fourth aspect, the present invention provides a method of sanitising, the method including applying sanitising solution according to the third aspect of the present invention to a target requiring sanitisation.

The solid sanitising composition according to the second aspect of the present invention may also include, as an active component, 0-35% by weight of the active components of a pH adjusting agent.

z? -ic- S :\P3a 43 .DOC !O/06O4 3 Preferably, the composition includes, as active components: 35-55% by weight oxidising agent, 12.5-30% by weight water softening agent, 3-10% by weight halide salt, 0.05-1% by weight surfactant, and 10-30% by weight pH adjusting agent.

The composition may further including inert components such as sodium sulphate and potassium sulphate as fillers or the like.

Preferably, the composition also includes a pneumatogenic agent to improve dissolution of the composition in water by affording vigorous effervescence to the composition on contact with water. The pneumatogenic agent may be an additional active component or pneumatogenicity may be afforded to the composition by one *or more of the active or inert components which has/have pneumatogenic properties. The pneumatogenic agent is preferably a water soluble carbonate, for example, sodium hydrogen carbonate, potassium carbonate, sodium carbonate, potassium hydrogen carbonate, or a mixture thereof.

"All of the active components are solids which may be mixed to form a powder composition. The powder composition may be compressed into blocks, prills, tablets or the like for ease of use and for improved protection against moisture contamination as compared with a powder. Where the composition is compressed it preferably contains additional acid to increase the speed of dissolution of the compressed product and a binder such as carboxymethylcellulose.

Suitable additional acids include citric acid, adipic acid, sulphamic acid and acid phosphates which may be present in the order of 5-20% by weight. Where a binder is used it 11 V*.y-m I,I P3 4443. [.DOC 26/05/00 4 would typically be present in the order of 0.5-1.5% by weight.

On dissolution in water, the oxidising agent oxidises the halide salt to form hypohalite which affords sanitising properties to the sanitising solution.

Preferably, the oxidising agent is selected from potassium monopersulphate, sodium monopersulphate, sodium percarbonate, sodium perborate or a mixture thereof. Sodium percarbonate when used as an oxidising agent is advantageous because it also functions as a pneumatogenic agent.

Potassium monopersulphate and sodium monopersulphate are superior oxidising agents to sodium percarbonate and sodium perborate due to their greater oxidising potential.

SPreferably, the halide salt is a chloride or bromide salt. Sodium chloride is the most preferred halide salt.

The water softening agent affords cleaning properties to the sanitising solution and slows down oxidation of the halide salt by the oxidising agent, thereby reducing loss of hypohalite to the atmosphere.

Preferably, the water softening agent is oxidation stable and is selected from salts of phosphoric acid, citric acid, ethylenediamine tetraacetic acid (EDTA), and polymeric water softening agents.

Preferably, the pH adjusting agent results in the pH of the sanitising solution being in the range 6-8, more preferably about 7. Preferably, the pH adjusting agent is selected from salts of carbonic acid which it is noted also have pneumatogenic properties. Sodium carbonate is the most preferred pH adjusting agent. It is a water scavenger and enhances stability of the solid sanitising composition which is moisture sensitive.

The surfactant of the sanitising composition reduces the surface tension of the sanitising solution enabling H:\sheriylm\keep\speci\P3R448.I.DOC 26/05/00 5 greater penetration of the sanitising solution into microscopic pores and cavities of the target to be sanitised, for example, a polymeric food preparation board.

Preferably, the surfactant is selected from oxidation stable anionic and cationic fluorosurfactants, for example, surfactants from the Zonyl (registered trade mark of DuPont) range and the Fluorad (registered trade mark of 3M company) range.

In addition to enhancing the wettability of the sanitising solution, it is believed that the presence of fluorosurfactant in the composition results in a residual film remaining on the target which is suspected to have a residual antibacterial effect.

The concentration of sanitising composition in the sanitising solution will, to a significant extent, be dependent upon the application to which the sanitising solution is to be put. Typically however, the sanitising solution will be formed by dissolving 0.5-5% by weight solid sanitising composition in water. It is to be noted that 20 dissolving the solid sanitising composition in water serves to both dilute the sanitising composition and activate the sanitising composition.

The sanitising solution is preferably used at ambient temperature because, although sanitising efficiency is increased at elevated temperature, loss of hypohalite to the atmosphere is enhanced.

EXAMPLES

Example 1 Preparation of Solid Sanitising Composition A solid sanitising composition was prepared by grinding 55g of potassium monopersulphate (oxidising agent), 24.95g of sodium tripolyphosphate (water softening agent), 15g of sodium carbonate (pH adjusting agent and pneumatogenic agent), 5g of sodium chloride (halide salt) and 0.05g of H: \sheTl kep\ SPeCi A 44 A. I DOC 26/05/00 6 Zonyl FSD (surfactant). The ground solids were thoroughly mixed with a spatula and samples placed in a tableting press to form 5g tablets.

Example 2 Preparation of Sanitising Solution A sanitising solution was prepared by placing one of the tablets from Example 1 in 500ml of water at ambient temperature. The tablet effervesced vigorously on contact with the water and was observed to be completely dissolved within 5 minutes. The resultant sanitising solution was found to have a pH of 7.1.

Example 3 Sanitising Efficiency The sanitising efficiency of the sanitising solution prepared in Example 2 was tested by treating agar plates and measuring bacterial colony growth. The sanitising solution was found to meet the requirements of the Therapeutic Goods Authority Test for disinfectants Option C (Commercial Grade Disinfectants) Example 4 Comparative Analysis A base for a sanitising composition was prepared by 20 grinding and thoroughly mixing 45% by weight potassium monopersulphate (oxidising agent), 12.5% by weight sodium Stripolyphosphate (water softening agent), 17.5% by weight sodium carbonate (pH adjusting agent and pneumatogenic agent), 5% by weight sodium chloride (halide salt), and by weight sodium sulphate (filler and moisture control agent) Samples of sanitising compositions were prepared by adding to 50 gram lots of the above sanitising composition base an amount of surfactant as set out in Table 1 below and thoroughly mixing the resultant composition.

H. shrylmlk-p ,pci PMA442. I DOC 26/05'00 7 TABLE 1 SANITISING COMPOSITION SURFACTANT A 0.05 grams of Zonyl® FSP B 1.5 grams of Nonoxynol 9 C 0.05 grams of Zonyl® FSD D 1.5 grams of Rhodafac®RA600 A series of trials were conducted using polyethylene cutting boards purchased from a supermarket.

In all trials the boards were washed with hot water and dish washing liquid, dried, contaminated with raw pork and chicken meat and contaminated with milk. Thereafter the contaminated boards were treated as set out in Table 2 below and then microbiological swabs were taken from the boards and incubated on agar plates. The agar plates were incubated for 72 hours at 25 0 C. Figures 1-7 are photographs of the agar plates from trials 1-7 respectively following incubation. Growth on the incubated agar plates was quantitatively assessed as Yes, No and Slight and the results are set out in Table 2.

go o BPI: Th 31-L Spec i P3A44.I I.DOC 29 05 00 8 TABLE 2 Trial Treatment Growth 1 Nil Yes 2 Washed with hot water and dish Yes washing liquid 3 Washed with hot water and dish Sight washing liquid followed by a sterilising solution formed by dissolving 10 grams of Sanitising Composition A per litre of ambient temperature water.

4 Washed with hot water and dish Sight washing liquid followed by a sterilising solution formed by dissolving 10 grams of Sanitising Composition B per litre of ambient temperature water.

Washed with hot water and dish No washing liquid followed by a sterilising solution formed by dissolving 10 grams of Sanitising Composition C per litre of ambient temperature water.

6 Washed with hot water and dish Slight washing liquid followed by a sterilising solution formed by dissolving 10 grams of Sanitising Composition D per litre of ambient temperature water.

7 Washed with hot water and dish Slight washing liquid followed by a commercially available disinfectant containing a quaternary ammonium compound as active ingredient.

Example 5 Meat Processing Plant A sanitising solution was formed by dissolving grams of Sanitising Composition C from Example 4 per litre of ambient temperature water.

The sanitising solution was used in a meat processing plant in lieu of a commercially available disinfectant following standard cleaning of various pieces of equipment. Following treatment with the sanitising solution, the equipment was tested for total H; Sh- 'IM 111-)sp c.P3R44-1. I DOC 26/05/00 9 bacteria and coliforms and the results are set out in Table 3.

TABLE 3 Department and Total Coliforms** Interpretation Area Bacteria* Cooked 1 0 Acceptable Meat Slicer Raw Slicer 1 0 Acceptable Bandsaw 0 0 Acceptable Linker 0 0 Acceptable Bowl Cutter 0 0 Acceptable Mincer 0 0 Acceptable a. a. a a (Grade 4 Unacceptable) (Grade 1 Unacceptable) Example 6 Bacteriostatic Action Agar plates were prepared with lawn cultures of the challenge microorganisms. Up to five wells were aseptically cut into the agar layer using a flame sterilised 5mm cork borer.

\\P.ISihooe$\Shr yl\i)eeP.SP.nC.\P3'.. I DOC 29,05 00 10 Controls Rationale Procedure Expected Result Media Test media Incubate 1 x Test invalid sterility sterility uninoculated if growth agar plate occurs Incubate 37 0

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48 hrs Sample Sample 20pl of Test invalid Sterility sterility sample into if growth NBt tube, occurs incubate 37°C 48 hrs inoculum Culture Examine test Test invalid Fertility viability plates for if no growth lawn growth occurs

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Reference: Pharmaceutical Microbiology 4 th Edition, Hugo W B Russell AD 1987 p267 3.4.1.

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The test procedure involved placing 0.lml of the sample into the well of the lawn culture plate, incubating at 37 0 C for 48 hours, and measuring the radius of the zone of inhibition of growth in mm with a radius of >6.5mm being 10 regarded as significant.

The results are set out in Table 4. The Inventive Sample was prepared by dissolving Sanitising Composition C from Example 4 in standard hard water as per EML 3-31-0 to a concentration of 100ppm and the Control Sample was prepared by dissolving chlorine in standard hard water as per EML 3-31-0 to a concentration of 100ppm.

RP1 I. -m Sh- yMEf)ep\%SIeCi\P3R44 .1DOC 29/05/00 11 TABLE 4 Sample Escherichia Vibrio Legionella Results coi cholera pneumophila Comment SG1 Inventive 26 18 14 Sample Inventive 22 12 10 PASS Sample Inventive 24 10 Sample Control 10 10 13 PASS Sample 0@

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5550 S 55 S. S S. S S S 55 H, Shrl 4 ,-Ci P3.'443 I DOC 26,05/00

Claims (4)

1. A solid sanitising composition including, as active components, an oxidising agent, a water softening agent, a halide salt and a surfactant, the composition being arranged such that a solution formed by dissolving the composition in water has a pH in the range 6-8.

2. A solid sanitising composition including, as active components:

15-60% by weight oxidising agent, 15-70% by weight water softening agent, 1-20% by weight halide salt, and 0.05-3% by weight surfactant; the composition being arranged such that a solution formed by dissolving the composition in water has a pH in the range 6-8. 3. A composition as claimed in claim 2 further including, as an active component, 0 35% by weight of the active components of a pH adjusting agent. 4. A composition as claimed in claim 3 containing, as active components:

35-55% by weight oxidising agent, 12.5-30% by weight water softening agent, o^ 3-10% by weight halide salt, o'oe 0.05-1% by weight surfactant, and 25 10-30% by weight pH adjusting agent. 5. A composition as claimed in any one of the preceding claims further including a pneumatogenic agent. 6. A composition as claimed in claim 5 wherein the pneumatogenic agent is a water soluble carbonate. 7. A composition as claimed in claim 6 wherein the water soluble carbonate is selected from the group consisting of sodium hydrogen carbonate, potassium h s oni, r. P 33-4 .1 DOZ: DS I I 13 carbonate, sodium carbonate, potassium hydrogen carbonate, and mixtures thereof. 8. A composition as claimed in any one of the preceding claims wherein the oxidising agent is selected from the group consisting of potassium monopersulphate, sodium monopersulphate, sodium percarbonate, sodium perborate and mixtures thereof. 9. A composition as claimed in any one of the preceding claims wherein the halide salt is a chloride salt, a bromide salt, or a mixture thereof. A composition as claimed in any one of the preceding claims wherein the water softening agent is selected from the group consisting of salts of phosphoric acid, citric acid, ethylenediamine tetraacetic acid (EDTA), and polymeric water softening agents. S11. A composition as claimed in any one of claims 3 wherein the pH adjusting agent is sodium carbonate. 12. A composition as claimed in any one of the preceding claims wherein the surfactant is selected from oxidation stable anionic and cationic fluorosurfactants. 13. A sanitising composition substantially as herein *described in Example 1 or Table 1. 14. A sanitising solution formed by dissolving a composition as claimed in any one of the preceding claims in 25 water. 15. A method of sanitising, the method including applying a sanitising solution as claimed in claim 14 to a target requiring sanitisation. Dated this 1 8 th day of June 2004 CLEARWATER CONCEPTS PTY LTD By its Patent Attorneys GRIFFITH HACK H Shievy!t Sp-2cOP3244 I DOC 13 33 .1