GB2358139A

GB2358139A - Disinfectant composition

Info

Publication number: GB2358139A
Application number: GB0000424A
Authority: GB
Inventors: Robert Vern Channer
Original assignee: Reckitt and Colman Products Ltd; Reckitt Benckiser UK Ltd
Current assignee: Reckitt Benckiser UK Ltd; Reckitt Benckiser Healthcare UK Ltd
Priority date: 2000-01-11
Filing date: 2000-01-11
Publication date: 2001-07-18
Also published as: GB0000424D0; WO2001051100A1; AU2001226902A1

Abstract

Air is disinfected by burning a disinfectant composition comprising a disinfectant, preferably a glycol, and a fuel, preferably an alcohol or a liquid hydrocarbon. The composition may further include water, a perfume and a malodour counteract. A catalytic burner is preferably used to burn the composition.

Description

2358139 Improvements in or Relating to organic Compositions The present

invention relates to a method for disinfecting the air which comprises combusting a disinfecting composition in a catalytic burner wherein the disinfecting composition comprises a fuel and a disinfectant.

It is well known that air-borne bacteria can facilitate the spread of disease. Accordingly various methods have been tried to sanitise the air. These methods rely upon different ways of getting the disinfectant into a form where it can sanitise the air. For example aerosols have been used. Also electrical devices which comprise a heating element which indirectly heats a pad or wick saturated with a disinfecting composition are known. The problem with these methods is that the distribution of the disinfectant throughout the space in which the device is placed is unsatisfactory. A solution to this problem has been sought.

According to the present invention, there is provided a method of disinfecting the air which method comprises burning a disinfectant composition which comprises a disinfectant and a fuel. The method preferably comprises catalytic burning.

A suitable disinfectant for use in the invention is a disinfectant which is able zo be volatilised at the temperature of combustion and which is effective at killing airborne bacteria. The temperature at which combustion takes place depends on the nature of the catalyst and the fuel.

For example a glycol, such as propylene glycol, dipropylene glycol, tripropylene glycol, ethylene glycol, diethylene glycol and/or triethylene glycol, is suitable for use as the disinfectant.

A suitable fuel for use in the invention is an alcohol (for example methanol ethanol, isopropanol and/or n-propanol) and/or a liquid hydrocarbon (such as benzene or a liquid alkane for example heptane or octane).

optionally the disinfectant composition additionally comprises a perfume and, optionally, a malodour counteractant.

A suitable perfume for use in the invention comprises one or more fragrant materials such as cedarwood oil, sandalwood oil, bergamot, Bulgarian rose oil, patchouli, myrrh, clove leaf oil, linalol, ethyl alcohol, terpineol, menthol, citronellal, and/or phenyl ethyl alcohol.

A suitable malodour counteractant for use in the invention is one or more aroma and/or non-aroma chemicals which are known to have an action in reducing the perception of the intensity of malodours e.g. unsaturated esters, ketones, aldehydes, and/or a fragrant material e.g. citronellal and/or cedarwood oil (which is known to counteract the perception of tobacco malodour).

According to a preferred embodiment of the invention, the disinfectant composition used in the invention comprises:

(a) from 50% (preferably from 75%) to 99% (preferably to 98%, more preferably to 95%) by weight 5 of a fuel; (b) from 1% (preferably from 2%, more preferably from 5%) to 50% (preferably to 25%) by weight of a disinfectant; and, optionally, (c) from 0% to 10% by weight of water, from 0% to 20% (preferably to 10%, more preferably to 3%) by weight of a perfume and/or from 0% to 5% by weight of a malodour counteractant.

The composition used in the invention is preferably substantially free from water.

According to the invention there is further provided a kit comprising:

(a) a burner; (b) a disinfectant composition which comprises a disinfectant and a fuel; and (c) instructions for the use of disinfectant composition (b) in the burner (a) to disinfect air.

According to the invention there is also provided a kit comprising:

(a) a disinfectant composition which comprises a disinfectant and a fuel; and (b) instructions for the use of disinfectant composition (a) in a burner to disinfect air.

According to the invention there is provided use of a disinfectant composition in a burner to disinfect air which composition comprises a disinfectant and a fuel.

The method of the invention is preferably carried out using a catalytic burner. A catalytic burner for use in the invention preferably comprises a reservoir for the fuel, a burner head and a wick to transport the fuel from the reservoir to the burner head. The burner head is optionally made from a refractory wool, a porous ceramic material or an inorganic mesh material (such as a metallic gauze). It is impregnated by a catalytic material which is usually based on platinum, palladium, rhodium and/or a combination thereof with another catalytically active metal, complex and/or ceramic Suitable catalytic burners are disclosed in EP-B-277875, FR-A-2 579 465 and FR-A-2 680 118.

The advantage of the present invention is that the convection currents which are generated when..the disinfectant composition is burnt ensure that the disinfectant is widely disseminated throughout the space in which the method of the invention is carried out. Surprisingly the disinfectant is not itself burnt during burning of the composition, especially during the catalytic burning of the composition.

The invention is illustrated by the following Examples which are not intended to limit the scope of the invention.

Preparation A A disinfectant composition suitable for use in the invention were prepared by mixing the following ingredients.

95% Isopropanol, 2% Tri-ethylene glycol, and 3% Water; wherein the percentages given are percentages by weight.

Preparation B A disinfectant composition suitable for use in the invention were prepared by mixing the following ingredients.

95% Isopropanol, and 5% Tri-ethylene glycol; wherein the percentages given are percentages by weight.

Example

A method according to the invention was carried out as follows using the compositions according to Preparations A and B. A comparative composition containing 95% by weight of isopropanol and 5% by weight of water was also used. The method was carried out using a catalytic burner as described in EP-B-277875 which burner comprises a reservoir for the fuel, a ceramic burner head impregnated with catalyst and a wick to transport the fuel from the reservoir to the burner head. In the method the compositions were tested for their effectiveness at inactivating airborne Micrococcus luteus in the aerosol state.

-M The test micro-organism used was the type strain of Micrococcus luteus (ATCC4698, NCTC2665) A freeze dried vial of the micro-organism was obtained from the National Collection of Industrial and Marine Bacteria (Torry, Aberdeen) The contents were resuspended in nutrient broth and plated out on Tryptone Soya Broth agar (TSBA) plates. The plates were incubated at 3CC for 72 hours and colonies were used to innoculate 500 mi flasks containing 50 ml of nutrient broth. The flasks were incubated at 3CC for 48 hours in shaking incubator. The resulting suspension of M. luteus was centrifuged and washed three times in sterile distilled water. This stock suspension was assayed and found to have a concentration of 5 x 109 cells/ml. This suspension was stored at CC before use. A ten-fold dilution of this suspension in distilled water was used as the spray suspension. The suspension was assayed before the first control run and after the final runs and was found to contain 6.0 x 108 and 7.0 x 10' cfu/mi respectively.

The method was carried out in a room having dimensions of 3.Om by 3.1m by 2.3m high. The room is fitted with a HEPA filtered air supply and extract system which allows the room air to be flushed before experiments to remove any background microbial aerosol.

Whilst the method was carried out, the ventilation system was switched off.

The spray suspension was aerosolised for one minute using a three jet Collison nebuliser (May 1973) operating at 18.3 x 103 kg /M2. The nebuliser produces an aerosol of low particle size (greater than 85% of the particles produced have a size of less than 2 pim).

A fan was operated during spraying and for an additional minute after spraying to disperse the aerosol before sampling was undertaken.

The air in the room was tested using two Casella slit samplers (Casella, London) which were operated at a flow rate of 30 1/min to take 60 regular 5 second samples over a two hour period beginning two minutes after the commencement of nebulisation. Five all glass impingers, operating at 12 1/min, were used to sample the aerosol for five minutes at time periods of minutes, 15 minutes, M minutes, one hour and two hours after nebulisation. The detection limit of the All Glass Impinger is 0.8 cells per litre.

Before the method according to the invention was carried out, two control runs were carried out. Then runs were performed with the catalytic burner and each of the compositions of Preparations A and B and the comparative composition. For each run, the catalytic burner was lit in the room 1 hour before the microbial suspension was nebulised.

The Micrococcus luteus decay curves measured by the Casella slit sampler are shown graphically in Figure 1 wherein the open triangular and square symbols represent the results obtained for the control runs, the black circles represent the results for the run with the comparative composition and the white diamonds and black stars are for the runs with the compositions for Preparations A and B, respectively.

no The Micrococcus luteus decay curves measured by the j All Glass Impinger (AGI) are shown graphically in Figure 2 wherein the symbols have the same meaning as for Ficure 1.

Both tile Casella and the AGI results clearly show that when the compositions of Preparative Examples 1 and 2 were used in the catalytic burner, there was a significant increase in the decay rate of M. luteus in the air. The vapourisation of the comparative composition caused no increase in the decay rate compared with the controls. Both of the compositions according to Preparations A and B caused an approximate 2 log drop in airborne M. Luteus numbers within a 30 minute period. The rate of decay using the composition according to Preparation B was slightly greater than that with the composition of Preparation A which is believed to be due to the higher concentration of triethylene glycol in the sample.

Claims

1 A method of disinfecting air which method comprises burning a disinfectant composition which comprises a disinfectant and a fuel.

2. A method according to claim 1 wherein the method comprises catalytic burning.

3. A method according to claim 1 or claim 2 wherein the disinfectant composition comprises:

(a) from 50% to 99% by weight of a fuel; (b) from 1% to 50% by weight of a disinfectant; and, optionally, (c) from 0% to 10% by weight of water, from 0% to 20% of a perfume and/or from 0% to 5% by weight of a malodour counteractant.

4. A method according to any one of the preceding claims wherein the disinfectant is a glycol.

5. A method according to any one of the preceding claims wherein the fuel is an alcohol or a liquid hydrocarbon.

6. A method according to any one of the preceding claims wherein the burning is carried out in a burner which comprises a reservoir for the fuel, a bu-rner head and a wick to transport the fuel from the reservoir to the burner head, wherein the burner head is impregnated with a catalytic material.

7. A method according to claim 6 wherein the catalytic 30 material is platinum, palladiumf rhodium and/or a combination thereof with another catalytically active metal, complex and/or ceramic.

8. A method of disinfecting the air substantially as hereinbefore described in the Example.

9. A kit comprising:

10. A kit comprising:

(a) a disinfectant composition which comprises a disinfectant and a fuel; and (b) instructions for the use of disinfectant composition (b) in a burner to disinfect air.

11. A kit according to claim 9 or claim 10 wherein the burner is a catalytic burner.

12. A kit according to claim 11 wherein the catalytic burner comprises a reservoir for the fuel, a burner head and a wick to transport the fuel from the reservoir to the burner head, wherein the burner head is impregnated with a catalytic material.

13. A kit according to claim 12 wherein the catalytic material is platinum, palladium, rhodium and/or a combination thereof with another catalytically active metal, complex and/or ceramic.

14. A kit according to any one of claims 8 to 13 wherein the disinfectant composition comprises:

(a) from 50% to 99% by weight of a fuel; (b) from 1% to 50% by weight of a disinfectant; and, optionally, 5 (c) from 0% to 10% by weight of water, from 0% to 20% of a perfume and/or from 0% to 5% by weight of a malodour counteractant.

15. A kit according to any one of claims 8 to 14 wherein the disinfectant is a glycol.

16. A kit according to any one of claims 8 to 15 wherein the fuel is an alcohol or a liquid hydrocarbon.

17. Use of a disinfectant composition in a burner to 15 disinfect air which composition comprises a disinfectant and a fuel.

18. Use according to claim 17 wherein the burner is a catalytic burner. 20

19. Use according to claim 17 or claim 18 wherein the disinfectant composition comprises: (a) from 50% to 99% by weight of a fuel; (b) from 1% to 50% by weight of a disinfectant; and, optionally, 25 (c) from 0% to 10% by weight of water, from 0%- to 20% of a perfume and/or from 0% to 5% by weight of a malodour counteractant. 30