MXPA01000029A - Malodour counteracting treatment - Google Patents

Abstract

A method of counteracting or neutralising airborne malodour comprising directing at the source of the malodour liquid droplets from a spray device containing a malodour counteracting composition, the method comprising imparting a unipolar charge to the said liquid droplets by double layer charging during the spraying of the liquid droplets by the spray device, the unipolar charge being at a level such that the said droplets have a charge to mass ratio of at least +/- 1 x 10-4 C/kg.

Description

TREATMENT FOR COUNTERING THE BAD ODORS The present invention relates to the treatment of odors, particularly bad odors carried in the air that can be caused or carried by particles carried in the air or by entities in a gaseous state. A known method for counteracting or neutralizing malodor includes the use of an aerosol spray device containing a composition comprising one or more agents that counteract malodor and which, when activated, produces an aerosol spray that can be directed towards the source of the bad smell. Several known products are marketed for this purpose. When the odor is caused totally or partially by particles carried in the air, a low frequency of collision occurs between the agent that counteracts the bad odor and the particles that cause the bad odor when using known aerosol devices and consequently the result is an inefficient process of counteracting the bad smell. The practical consequence of this inefficiency is that the agent that counteracts the bad smell must be used in large quantities in order to achieve the desired effect. This in turn causes unwanted side effects such as, for example, a strong perfume or a limited choice of fragrances. Even when the malodour is caused wholly or partially by a source other than airborne particles, the use of known aerosol spray devices containing compositions that counteract malodor remains relatively inefficient. To provide an aerosol spray that can be projected over a reasonable distance, the design of the device, and particularly the design of the spray head of the device, results in the emission of a spray with a small spray angle. Thus, most of the spray is displaced at least initially along or near a central spray line extending from the spray head. Accordingly, if the source of the nal odor is spread over a spatially significant distance in lateral directions relative to the spray line, it is necessary to supply a large amount of aerosol spray in order to effectively eliminate the malodor. Thus, to remove the bad smell of a room, a quantity of aerosol spray is required in the space of the room. We have now developed an improved method to counteract or neutralize a bad smell carried in the air.

Accordingly, the present invention provides a method for counteracting or neutralizing a bad odor carried in the air which comprises directing to the source of the malodor small droplets of liquid from a spray device containing a composition that counteracts the odor, the method comprises the supply of a unipolar charge to said small drops of liquid by means of a double layer charge during the spraying of the small drops of liquid by the spraying device, the unipolar charge is at a level such that said small droplets have a charge to mass ratio of at least +/- 1 x 10"4 C / g.The method of the present invention allows a bad odor carried in the air, for example, in a room or in another enclosed space, it has been effectively treated that the cause of the bad smell is from a source of particles, such as smoke, or from a gaseous origin, such as kitchen odors, or from small ones drops of liquid finely dispersed, or of resinous material. The method of the present invention is extremely effective in counteracting or neutralizing odors since small droplets of charged aerosol spray have a higher frequency of collision with the particles causing the odor contained in the air. In addition, since the small charged droplets carry the same charge polarity when sprayed from the spray device, they are rejected between them and therefore they extend more from the central spray line than they would if they were not loaded in accordance with the invention. Thus, the spray covers a greater volume of air space than in the case of a conventional air spray, allowing a more effective treatment for a lower volume of spray than in the case of a conventional spray device. It is preferred that the unipolar charge provided to the small drops of liquid is generally only through the interaction between the liquid within the spraying device and the spraying device itself as the liquid is sprayed therefrom. Particularly, it is preferred that the way how a unipolar charge is provided to the small droplets of liquid is not even partially based on the connection of the spraying device with any external charging induction device such as a relatively high voltage source, for example. or any other internal charge induction device, such as a battery. With an arrangement of this type, the spray device is completely autonomous, and therefore suitable for industrial, institutional and domestic use. Preferably, the spraying device is a domestic pressure spraying device that has no electrical circuit but can be manually operated. Typically, a device of this type has a capacity within a range of 10 ml to 2000 ml and can be operated manually, or through an automatic drive mechanism. A particularly preferred household device is a manual aerosol can.

Preferably, therefore, the ratio between the charge of the small drops and the mass is at least +/- 1 x 10"4 C / kg and is provided to the small drops of liquid as a result of the use of a device aerosol spray with at least one of the characteristics of actuator material, size and shape of the actuator orifice, diameter of the immersion tube, characteristics of the valve and formulation of the composition that counteracts the malodor contained in the device spray being selected in order to achieve said ratio between small droplet charge and mass by a double layer charge by providing a unipolar charge to the small droplets during the actual spraying of the small droplets of liquid from the orifice of the spray device of As a result of the method of the present invention, a malodour control is observed with the use of a much smaller amount of counterstaining composition. the bad smell that in the case of the prior art. Furthermore, taking into account the increased frequency of collision between the airborne particles and the agent that counteracts the bad odor and the increased spray of the aerosol spray for a given amount of sprayed liquid from the aerosol, the efficiency of the spray is increased. agent that counteracts the bad smell.

These results are achieved due to the fact of the important unipolar charge provided to the small drops of liquid from the aerosol spray. The individual small droplets carry the same polarity charge and therefore focus on the malodorous particles that have the opposite charge or that are electrically neutral. In addition, • since the small charged droplets are rejected between them, no coalescence of the small droplets is observed or the coalescence level is low. On the contrary, the small charged droplets tend to have a greater dispersion compared to the small uncharged droplets. In addition, if the forces of repulsion from the charge within the small droplets is greater than the surface tension force of the small droplets, the small charged droplets are fragmented into several small smaller charged droplets (exceeding the Rayleigh limit). This process continues until the two opposing forces equalize or until the small drop evaporates completely. The malodorous particles are normally electrically isolated from their environment and typically find themselves in a potential that is the same as the potential of their environment. In this situation, a particle of bad odor located within a cloud of electrically charged small liquid droplets probably causes a distortion of the configuration of the electric field generated by the small droplets in such a way that it improves the. attraction of the small drops towards the particles. That is equivalent to focusing each particle of bad smell. Examples of agents that counteract the bad odor that can be used in the method according to the present invention are those that form all or part of the following currently available products: Arbor Vitae, benzyl salicylate, chlorophyll, cyclodextrins, d-limonene , flavanoids, Hinoki oil, parsley extract, phthalocyanine, saponin, tea tree oil, Tego Sorb (T.H. Goldschmidt), Veilex I, II or III (Bush Boake Alien) as well as the two aldehyde system described in US Patent No. 5795566. The liquid composition that is sprayed into the air using the aerosol spray device is preferably a mixture of water and hydrocarbon, or emulsion, or a liquid that is conveyed in an emulsion by stirring. of the spraying device before use, or during the spraying process. An example of an aerosol composition for home use that is in a form suitable for spraying in accordance with the method of the present invention is given in the examples presented below. While it is known that all liquid aerosols carry a negative charge or a net positive charge as a result of a double layer charge, or due to the fragmentation of the small drops of liquid, the charge provided to the small drops of the liquid sprayed from standard devices is only of the order of +/- 1 x 10"8 to 1 x 10" "C / This invention is based on the combination of several characteristics of the design of an aerosol spray system in order to increase the loading of the liquid during its spraying from the aerosol spray device.A typical aerosol spray device comprises : 1. An aerosol can containing the composition to be sprayed from the device and a liquid or gaseous impeller; 2. A dip tube that extends into the can, the top end of the dip tube is connected to a valve; 3. A drive device placed above the valve which may be depressed for the purpose of operating the valve; 4. An insert provided in the drive device comprising an orifice from which the composition is sprayed. An aerosol spray device for use in the present invention is described in WO 97/12227. It is possible to provide higher loads to the small droplets of liquid by choosing aspects of the aerosol device which includes the material, shape and dimensions of the drive device, the drive device insert, the valve and the tube. immersion and the characteristics of the liquid to be sprayed in such a way that the required level of charge is generated as the liquid is dispersed in the form of small droplets. Several characteristics of the aerosol system increase the double-layer loading and the exchange of charge between the liquid formulation and the surfaces of the aerosol system. Such increases are caused by factors that can increase the turbulence of the flow through the system, and increase the frequency and speed of contact between the liquid and the internal surfaces of the container and valve and drive system. By way of example, characteristics of the drive device can be optimized in order to increase the load levels in the spray liquid = from the container. A small hole in the drive device insert, of a size of 0.45 mm or less, increases the charge levels of the sprayed liquid through the drive device. The choice of material for the drive device can also increase the load levels in the sprayed liquid from the device with material, for example nylon, polyester, acetal, PVC and polypropylene tending to increase the load levels. The geometry of the hole in the insert can be optimized in order to increase the load levels in the liquid as it is sprayed through the drive device. Inserts that promote mechanical rupture of the liquid offer a better load. The insert of the drive device of the atomization device can be formed from a conducting material, semiconductor insulator or aesthetic-dissipater. The characteristics of the immersion tube can be optimized in order to increase the load levels in the liquid sprayed from the container. A narrow immersion tube, for example of approximately 1.27 mm internal diameter, increases the charge levels in the liquid, and the material of the dip tube can also be changed in order to increase the load. The characteristics of the valve can be selected in order to increase the ratio between load and mass of the liquid product as it is sprayed from the container. A small tailpiece hole in the cover, approximately 0.65 mm, increases the ratio between the load and the mass of the product during spraying. A small number of holes in the rod, for example 2 x 0.50 mm, also increases the load of the product during spraying. The presence of a vapor phase tap helps to optimize the charge levels, a large orifice vapor phase tap, for example from about 0.50 mm to 1.0 mm generally provides higher levels of charge. Changes in product formulation can also affect load levels. A formulation containing a mixture of hydrocarbon and water, or an emulsion of a non-miscible hydrocarbon and water, will provide a higher charge to mass ratio when sprayed from the aerosol device than a water alone formulation or a formulation of hydrocarbon only. It is preferred that a malodor neutralization composition for use in the present invention contain an oil phase, an aqueous phase, a surfactant, an agent that counteracts odors and an impeller. Preferably, the oil phase includes a Cg C12 hydrocarbon preferably present in the composition in an amount of 2 to 10% w / w. Preferably, the surfactant is glyceride oleate or a polyglycerol oleate, preferably present in the composition in an amount of 0.1 to 1.0% w / w. Preferably, the impeller is liquefied petroleum gas (LPG) which is preferably butane, optionally in admixture with propane. The impeller may be present in an amount of 10 to 90% w / w depending on whether the composition is contemplated for spraying in the form of a "wet" composition or in the form of a "dry" composition. In the case of a "wet" composition, the impeller is preferably present in an amount of 20 to 50% w / w, preferably in an amount of 30 to 40% w / w. Small droplets of liquid sprayed from the aerosol spray device will generally have diameters within a range of 5 to 100 micrometers, with a peak of small droplets of approximately 40 micrometers. The liquid that is sprayed from the aerosol spray device may contain a predetermined amount of a particulate material, for example, fumed silica, or a predetermined amount of a volatile material such as, for example, menthol or naphthalene. The method of the present invention during the process of counteracting bad odors, also accelerates the natural process of precipitation of particles carried in the air by indirectly charging the particles, thus allowing to improve quickly and conveniently the quality of the air. Examples of malodors counteracted, neutralized or reduced by the method of the present invention include tobacco smoke as well as vehicle exhaust smoke. A can for a typical aerosol spray device is formed of aluminum or of a lacquered or unlacquered tin plate or the like. The drive device insert can be formed, for example, of acetal resin. The lateral opening of the valve stem can typically be in the form of two openings of diameters of 0.51 mm. The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic cross section through an aerosol spray apparatus in accordance with the present invention; Figure 2 is a diagrammatic cross section through the valve assembly of the apparatus of Figure 1; Figure 3 is a cross-section through the drive device insert of the assembly illustrated in Figure 2; Figure 4 shows the configuration of the orifice of the spray head shown in Figure 3 when viewed in the direction A; and Figure 5 shows the configuration of the swirl chamber of the spray head shown in Figure 3 when viewed in the direction B. With reference to Figures 1 and 2, an aerosol spray device of according to the present invention. Said device comprises a can 1, formed of a lacquered or unlacquered tin or aluminum plate or the like in a conventional manner, which defines a reservoir 2 for a liquid 3 having a conductivity such that the small drops of the liquid can carry a proper electrostatic charge. Also within the can is a gas under pressure which is capable of pushing the liquid 3 out of the can 1 through a duct system comprising a dip tube 4 and a valve and a drive device assembly 5. The dip tube 4 includes an end 6 terminating in a peripheral part of the can bottom 1 and another end 7 connected to the tail part 8 of the valve assembly. The tailpiece 8 is fixed through a mounting assembly 9 installed in an opening in the upper part of the can and includes a lower portion 10 defining a tailpiece orifice 11 where the tube end 7 is connected. 4. The tailpiece includes a perforation 12 of a relatively narrow diameter in a lower portion 11 and a relatively wider diameter in its upper portion 13. The valve assembly also includes a rod tube 14 mounted within the bore. 12 of the tailpiece and positioned to be axially displaced within the bore 12 due to the action of the spring 15. The valve rod 14 includes an internal bore 16 having one or more side openings (bore holes) 17 ( see Figure 2). The valve assembly includes a drive device 18 having a central bore 19 which houses the valve rod 14 in such a manner that the bore 16 of the rod tube 14 is in communication with the bore 19 of the drive device. A passage 20 in the drive device extending perpendicularly relative to the bore 19 joins the bore 19 with a recess including a post 21 in which a spray head is mounted in the form of an insert 22 including a bore 23 in communication with the passage 20. A ring 24 of elastomeric material is provided between the external surface of the valve stem 14 and, usually, this seal ring closes the side opening 17 in the valve stem 14. The construction of the valve assembly is such that when the actuating device 18 is manually depressed, it pushes the valve rod 14 downwards against the action of the spring 15 as shown in FIG. 2 in such a way that the seal ring 24 already it does not close the side opening 17. In this position, a path from the reservoir 2 to the perforation 23 of the spray head is provided in such a way that the liquid can be pushed, under the pressure of the gas in the can, towards the head sprayed through a duct system comprising the dip tube 4, the tailpiece bore 12, the valve stem bore 16, the drive device bore 19 and the passage 20. A bore 27 (not shown in Figure 1) is provided in the wall of the glue piece 8 and constitutes a vapor phase socket whereby the gas pressure in the tank 2 can act directly on the liquid flowing to the tank. through the valve assembly. This increases the turbulence of the liquid. It has been found that an increased load is provided if the diameter of the hole 27 is at least 0.76 mm. Preferably, the lateral opening 17 joining the valve stem bore 16 with the tailpiece bore 12 has the shape of two holes, each with a diameter not greater than 0.51 mm in order to increase the generation of electrostatic charge. In addition, the diameter of the dip tube 4 is preferably as small as possible, for example 1.2 cm, in order to increase the charge provided to the liquid. Also, the charge generation is increased if the diameter of the tailpiece hole 11 is as small as possible, for example, no more than about 0.64 mm. Referring now to Figure 3, a cross-section through the drive device insert of the apparatus of Figures 1 and 2 is shown on an enlarged scale. For simplicity, the perforation 23 is shown in the form of a single cylindrical aperture. in this Figure. However, the perforation 23 preferably has, for example, the configuration illustrated in Figure 4. The apertures in the perforation 23 are indicated by the reference number 31 and the portions defining the apertures in the perforation are indicated through of the reference number 30. The total peripheral length of the portions defining the openings in the perforation outlet is indicated by L (in mm) since it is the total area of the opening in the perforation outlet (in mm2) and the values of L are already indicated in Figure 4. L / a is greater than 8 and this condition is especially suitable for load development since it means an increased contact area between the drive device insert and the fluid that go through. Many different configurations can be adduced in order to produce a high L / a ratio without reducing the cross-sectional area to a value that would allow only low fluid flow rates. Thus, for example, it is possible to employ driving device insert piercing configurations (i) wherein the piercing outlet comprises a plurality of segment-type openings (with or without a central opening).; (ii) where the outlet comprises several openings of the sector type; (iii) where the openings together form an outlet in the form of a grill or grid; (iv) where the exit is generally cross-shaped; (v) where the openings together define an outlet in the form of concentric rings; and combinations of these configurations. Drive insert insert drilling configurations are particularly preferred wherein a tongue-like portion protrudes into the liquid flow stream and can be vibrated in this manner. This property of vibration can cause a turbulent flow and improve the separation of electrostatic charge from the double layer, allowing a greater load to move in the volume of the liquid. Referring now to Figure 5, a plan view of a possible configuration of a swirl chamber 35 of the drive device insert 22 is shown. The swirl chamber includes 4 lateral channels 36 equally spaced and tangential relative to an area central 3"qce surrounds the perforation 23. In use, the liquid pushed from the reservoir 2 by the gas under pressure travels along the passage 20 and hits the channels 36 in a normal manner with respect to the longitudinal axis of the channels. The positioning of the channels is such that the liquid tends to follow a circular motion before entering the central area 37 and thence towards the perforation 23. As a consequence, the liquid is subjected to a substantial turbulence which increases the electrostatic charge in the The following examples illustrate the invention: EXAMPLE 1 A formulation for cooling the air was produced as follows: 83% by weight of a solvent of isoparaffin was introduced into a mixing and stirred vessel. 0.2% by weight of butylhydroxytoluene was added to the container as a corrosion inhibitor and stirred until a homogeneous mixture was obtained. Then, in turn, 5% by weight of a polyglycerol oleate emulsifier and 11.8% by weight of an agent that counteracts / neutralizes the bad odor were added, and stirring continued until a homogeneous mixture was obtained. This mixture constituted the oil phase of the final product. 6% by weight of this phase was placed in a tin coated aerosol can of the type described in relation to Figures 1 and 2 and with a spray head drilling configuration as shown in Figure 4 and a chamber configuration of swirls in accordance with that illustrated in Figure 5. The drive device insert was formed of acetal resin. The side opening 17 of the valve stem had the form of 2 openings with a diameter of 0.51 mm, the hole for taking the vapor phase 27 had a diameter of 0.76 mm, the hole 11 of the glue pipe had a diameter of 0.64 mm and the diameter of the dip tube 4 was 3 mm. Then 59% of soft water was added to the can and then the valve assembly was placed on the can. 35% by weight of butane in the can was introduced through the valve assembly to achieve a pressure of 28,124 kg / m2 (40 psi) inside the can. By pressing the drive device 18, a fine mist of small droplets of liquid having a charge to mass ratio of -1 x 10 ~ 4 C / kg and a flow rate of about 1.5 g / sec was obtained. The small drops quickly disperse in the air. The aerosol spray device described above was compared to a known, standard aerosol spray device loaded with the same aerosol formulation in the following test. Smoke odor control test The experiment was based on a panel. In order to be able to evaluate the results, it was necessary to measure the threshold levels of the members of the panel. By selecting the members of the panel with the same threshold value, a more accurate result could be obtained. TEST OF UMBI IL Six samples of fragrance were made with diethyl phthalate (DEP) in different concentrations of fragrance. They were placed in wide-necked, amber glass jars and marked as follows: A = 2% solution, 0.6 g of fragrance diluted with 29.4 g of DEP B = 0.5% solution, 0.15 g of fragrance diluted with 29.85 g of DEP C = 0.05% solution, 0.015 g of fragrance diluted with 29,985 g of D? PD = 0.005% solution, 0.0015 g of fragrance diluted with 29.9985 g of DEP E = 0.0005% solution, 0.00015 g of fragrance diluted with 29.99985 g of DEP F = standard, 30 g of DEP G = standard, 30 g of DEP A group of prospective panel members were asked to select " the fragrance that does not belong to the group "using F + G as standard samples all the time and any of the other samples. Starting with the strongest (A), they were asked to select three times the samples they suspected were the most fragrant. The prospective panel members who achieved consistently correct answers for the fragrances in the A - C ranks were selected as final panel members for the next experiment. It should be noted that none of the panel members could predict fragrance D with 100% certainty.

The test was carried out using three cabins with controlled temperature and humidity. In all the cabins, cigarette smoke was introduced through a device to artificially smoke two Marlborough cigarettes. After this, the cabins were treated as follows: Cab 1 0.5 g of normal aerosol spray was sprayed in the center of the cabin. Cabin 2 In this cabin 0.5 g of the electrostatically charged aerosol spray was introduced in the center of the cabin. Cabin 3 This cabin was left with only tobacco smoke added in order to remind the panel members of the bad smell of reference, as appropriate. Fifteen panel members were asked to select which booth between cabins 1 and 2 had the strongest bad smell of tobacco compared to booth 3. The results were interpreted statistically to establish a significance that showed that the dew was electrostatically charged the cabin 2 significantly reduced the perceived bad smell compared to the normal aerosol spray in the cabin 1. Additional examples of compositions that counteract the malodor are given below, which can be formulated in accordance with the method of example 1 above , EXAMPLE 2 Component% weight / weight Butane butane 40 35 Hydrocarbon Cg-C? 2 5.0 Poly glycerol oleate 0.30 Butylated hydroxytoluene 0.0130 Diethyl phthalate 0.70 Arbor Vitae 0.2 Soft water to form up to 100% EXAMPLE 3 Component% weight / weight Butane butane 40 35 Hydrocarbon C9-C12 5.0 Polyaglycerol Oleate 0.30 Butylated Hydroxytoluene 0.0130 Ityphthalate 0.70 Benzyl salicylate 0.2 Soft water up to 100% EXAMPLE 4 Component% weight / weight Butane builder 40 35 C9-C12 hydrocarbon 5.0 Polyglycerol oleate 0.30 Butylated hydroxytoluene 0.0130 Diethyl phthalate 0.70 Carra Odor 0.2 Soft water to make up to 100% One or more ce the following agents to counteract malodor can be used in compositions of example 1 to 4, instead of the agent to counteract the malodor of these examples. Arbor Vitae Benzyl salicylate Chlorophyll Cyclodextrins d-limonene 7 flavanoids Hinoti oil Phthalocyanine parsley extract saponin Tea tree oil Tego Sorb Veilex I, II or III (from Bus Boake Alien) and the system of two aldehydes described in the Patent North American No. 5795566.

Claims (13)

1. CLAIMS A method to counteract or neutralize the bad smell carried in the air, which comprises directing small droplets of liquid to the source of the odor from a spray device containing a composition that counteracts malodor, the method comprises the supply of a unipolar charge to said small droplets of liquid by means of double layer loading during the spraying of the small drops of liquid by the spraying device, the unipolar charge is at a level such that said small droplets have a relation between charge and a mass of at least +/- 1 x 10"4 C / kg A method according to claim 1 wherein the spraying device is an aerosol spray device A method according to claim 1 according to claim 2, wherein the composition that counteracts the malodor is an emulsion, a method according to the claim in any of the claims. above where small droplets of liquid have a diameter within a range of 5 to 100 micrometers. A method according to claim 1 in any of the preceding claims wherein the composition includes an agent that counteracts malodor that is selected from one or more of the following: Arbor Vitae, benzyl salicylate, chlorophyll, cyclodextrins, d-limonene , flavanoids, Hinoki oil, parsley extract, phthalocyanine, saponin, tea tree oil or Tego Sorb. A method according to claim 1 in any of the preceding claims wherein the unipolar charge is provided to the small drops of liquid only by the interaction between the liquid and the spraying device, without imparting any charge from an internal device or external load inductor. A method according to claim 6 wherein the ratio between charge and mass of the small droplets is at least / 1 X 10 ~ 4 C / Y. and is given to the small droplets of liquid as a result of the use of an aerosol spray device with at least one of the characteristics of the material of the drive device, the shape and size of the orifice of the drive device, the diameter of the dip tube, the characteristics of the valve and the formulation of the composition that counteracts the malodor contained within the aerosol device being selected in order to achieve said ratio between charge and mass of small droplets by means of a double layer charge that provides the unipolar charge to the small droplets during actual spraying the small drops of liquid from the orifice of the aerosol spray device. 8. A method of conformance to any of the preceding claims wherein the composition which counteracts malodor comprises an oil phase, an aqueous phase, a surfactant, an agent that counteracts malodor and a impellent 9. A method according to claim 8 wherein the oil phase includes a C9-C1? Hydrocarbon. 10. A method according to claim 9 wherein the hydrocarbon Cc, -Ci2 is present in the composition in an amount of 2 to 10% w / w. 11. A method according to any of claims 8 to 10 wherein the surfactant is 20 glyceryl oleate or a polyglycerol oleate. 12. A method according to any of claims 8 to 11 wherein the surfactant is present in the composition in an amount of 0.1 to 1.0% w / w. 13. A method according to any of claims 8 to 12 wherein the impeller is liquefied petroleum gas. A method according to claim 13 wherein the impellent is present in the composition in an amount of 20 to 50% w / w.