阅读说明：本技术 驱蚊剂组合物 (Mosquito repellent composition ) 是由 余慧芯 穆尼·塞利特 于 2018-12-03 设计创作，主要内容包括：本发明涉及一种驱虫剂组合物,其包含：蒸气活性拟除虫菊酯；可燃性散装材料；和粘结剂；其中蒸气活性拟除虫菊酯从选自甲氧苄氟菊酯、四氟苯菊酯、四氟甲醚菊酯、氯氟醚菊酯、瑞那富宁和七氟甲醚菊酯的组的一种或多种中选择。本发明也包括制备驱虫剂组合物的方法、包含该组合物的制品、包含此类制品的套组和通过点燃该组合物来驱离昆虫的方法。(The present invention relates to an insect repellent composition comprising: a vapor active pyrethroid; a combustible bulk material; and a binder; wherein the vapor-active pyrethroid is selected from one or more of the group consisting of metofluthrin, transfluthrin, meperfluthrin, permethrin, ryafurtinin and permethrin. The invention also includes methods of making the insect repellent compositions, articles of manufacture comprising the compositions, kits comprising such articles of manufacture, and methods of repelling insects by igniting the compositions.)

1. An insect repellent composition comprising:

a vapor active pyrethroid;

a combustible bulk material; and

a binder;

wherein the vapor-active pyrethroid is selected from one or more of the group consisting of metofluthrin, transfluthrin, meperfluthrin, ryafurthrin, and tetramethrin, and the vapor-active pyrethroid is present in an amount to provide a release rate of:

wherein the pyrethroid is metofluthrin, the release rate is 0.05 to 0.30 mg/min;

wherein the pyrethroid is transfluthrin, the release rate is 0.15 to 0.45 mg/min;

wherein the pyrethroid is permethrin, the release rate is 0.05 to 0.50 mg/min;

wherein the pyrethroid is meperfluthrin, the release rate is from 0.04 to 0.40 mg/min;

wherein the pyrethroid is linaflunine and the release rate is from 0.05 to 0.50 mg/min; and

wherein the pyrethroid is metaflumethrin and the release rate is from 0.05 to 0.50 mg/min.

2. The composition according to claim 1, wherein the pyrethroid is metofluthrin and the release rate is from 0.05 to 0.30 mg/min.

3. The composition according to claim 1, wherein the pyrethroid is transfluthrin and the release rate is from 0.05 to 0.50 mg/min.

4. The composition according to claim 1, wherein the pyrethroid is transfluthrin and the release rate is 0.15 to 0.45 mg/min.

5. The composition according to claim 1, wherein the pyrethroid is meperfluthrin and the release rate is from 0.04 to 0.40 mg/min.

6. The composition according to claim 1, wherein the pyrethroid is linaflunine and the release rate is 0.05 to 0.50 mg/min.

7. The composition according to claim 1, wherein the pyrethroid is heptaflumethrin and the release rate is 0.05 to 0.50 mg/min.

8. A composition according to any one of the preceding claims, wherein the pyrethroid is provided as the compound itself.

9. The composition according to any one of claims 1 to 7, wherein the pyrethroid is provided in the form of an emulsion concentrate or a microemulsion.

10. The composition according to any one of the preceding claims, wherein the combustible bulk material is in the form of a powder of one or more selected from the group consisting of wood, sawdust, paper, cardboard, coconut shell, flour made from leaves or other nut shells, jute, bagasse, rice hulls, tea leaves, coffee grounds, charcoal, and pyrethrum grounds.

11. The composition according to claim 10, wherein the combustible bulk material is one or more selected from the group consisting of wood flour, coconut shell flour, charcoal powder, and pyrethrum residue.

12. The composition of any one of the preceding claims, wherein the combustible bulk material is provided in an amount of 70 to 90% w/w.

13. The composition according to any one of the preceding claims, wherein the binder is selected from one or more materials selected from cypress flour, α -starch, Makko flour, incense flour, carboxymethyl cellulose, guar gum, tapioca starch, tamarind starch, and tamarind kernel flour.

14. The composition of claim 13, wherein the binder is cedar flour and/or α -starch.

15. The composition of any preceding claim, wherein the binder is provided in an amount of 5 to 40% w/w.

16. The composition of any one of the preceding claims, further comprising a preservative.

17. The composition of claim 16, wherein the preservative is selected from one or more materials selected from sodium dehydroacetate, potassium sorbate, and sodium benzoate.

18. The composition of claim 16 or 17, wherein the preservative is provided in an amount of 0.1 to 1.0% w/w.

19. The composition of any one of the preceding claims, further comprising at least one emulsifier.

20. The composition of any one of the preceding claims, further comprising at least one promoter or oxygen donor for fuel.

21. The composition of any of the preceding claims, further comprising at least one flame retardant.

22. The composition of any one of the preceding claims, further comprising at least one colorant and/or fragrance.

23. A method of preparing an insect repellent composition as defined in any one of the preceding claims, comprising the steps of:

a) providing a vapor-active pyrethroid;

b) providing a combustible bulk material;

c) providing a binder;

d) optionally, providing a preservative;

e) optionally, providing at least one additive selected from the group consisting of emulsifiers, promoters or oxygen donors for fuels, flame retardants, colorants, and fragrances; and

f) mixing the vapour-active pyrethroid, the combustible bulk material and the binder, and optionally the preservative and/or at least one of the additives, with the addition of water.

24. The method of claim 23, further comprising the step of forming the composition into an article.

25. An article of manufacture comprising an insect repellent composition as defined in any one of claims 1 to 22.

26. The article of claim 25, wherein the composition comprises a pyrethroid in the form of an emulsion concentrate or a microemulsion.

27. The article of claim 25 or 26, wherein the article is self-supporting.

28. The article of claim 27, wherein the article is substantially conical.

29. The article of any one of claims 25 to 28, weighing from 0.5 to 5.0 grams.

30. The article of claim 29, weighing from 0.8 grams to 3.0 grams.

31. The article of claim 30 having a weight of 1.0 to 2.0 grams.

32. The article of any one of claims 25 to 31, configured to burn for 10 to 60 minutes.

33. The article of claim 32, configured to burn for 15 to 40 minutes.

34. The article of claim 33, configured to burn for 20 to 30 minutes.

35. A kit comprising an article as defined in claim 25 which is not self-supporting and further comprising a base for supporting the article.

36. A method of repelling insects, wherein the method involves igniting an insect repellent composition as defined in any one of claims 1 to 22 or an article as defined in any one of claims 25 to 34 to repel insects.

37. The method of claim 36, wherein the insect is selected from one or more of the group consisting of a mosquito, midge, sand fly, black fly, house fly, jungle fly, mosquitos, horse fly, bee, wasp, ant, cockroach, leech, tick, and mite.

38. The method of claim 37, wherein the insect is a mosquito.

39. The method of claim 38, wherein the mosquito is a D-allethrin resistant mosquito.

Technical Field

The present invention relates to a composition and method for repelling insects, particularly flying insects such as mosquitoes.

Background

The listing or discussion of a prior-published document in this specification should not be taken as an admission that the document is part of the state of the art or is common general knowledge.

In many areas of the world, the humming of mosquitoes may not be merely distracting. It may be predictive that bites may transmit diseases such as malaria, dengue fever, flexo fever (chikungunya) and zika (zika) to individuals. As such, even when an individual attempts to protect themselves from bites using repellents, repellents may not be effective until the mosquito is within a few inches of the individual. The proximity of mosquitoes can cause an individual to feel a fire due to the constant humming of the mosquito and can even cause anxiety or fear if they are afraid of being bitten.

Other pest species may also pose a threat of biting or stinging on the individual, which may be irritating or, in the worst case, life threatening due to allergic reactions. Such species include, but are not limited to, midges, sand flies, black flies, house flies, jungle flies (bush flies), hair mosquitoes (march flies), horse flies, bees, wasps, ants, cockroaches, leeches, ticks, and mites. While most, but not all, of these species are not disease vectors, their presence in and around humans and animals can afflict the relevant individuals for a variety of reasons.

In view of the above, many efforts have been made and with varying degrees of success to keep these pests away from humans and/or animals. These efforts have generally focused on physical barriers, pesticide compositions, and insect repellent compositions.

Physical barriers such as mosquito nets, which may be impregnated with pesticides and/or insect repellents, have proven effective in preventing individuals from being bitten if a person is to remain in a place, such as a person sleeping in a bed. However, such barriers are impractical for people who are on the move (due to restricted movement) or in recreational environments, whether indoors or outdoors, where the barrier may prevent an individual from enjoying the surrounding environment.

Pesticides have had limited success in reducing or eliminating the threat of an individual being bitten while in an enclosed environment (e.g., indoors). The pesticide is provided in the form of an aerosol spray, a combustible mosquito coil, and an electronic device that releases the pesticide into the air over a period of time. All of these forms rely on the release of an effective amount of pesticide into the air in order to rid the space-specific pest species during the pesticide's effective period.

The active agents (particularly insecticides/pesticides) used in conventional mosquito coils are slowly released into the environment as the mosquito coil smolders. Mosquito coils (and similar products) therefore require an initialization time before they can provide a sufficient concentration of pesticide to an enclosed space to obtain an acceptable level of protection. In other words, the use of mosquito coils does not provide immediate protection against mosquitoes, resulting in an increased risk of the user being bitten by mosquitoes for a period of time that the user is supposed to be protected but is not actually present. Where mosquitoes are already resistant to some insecticides, a greater amount of insecticide needs to be brought into the environment before the mosquito is knocked down, thereby increasing the initialization time and also increasing the risk of mosquito bites. Conventional mosquito coils must also burn for long periods of time to provide protection. This means that if they are used indoors, for example to protect sleeping users, there is a risk of fire, or at least the possibility of discomfort to the user due to smoke generated when the mosquito coil burns.

JP2011012056 discloses a method for controlling pests wherein when burning mosquito coils, a release is made having a vapour pressure of 2 × 10 at 30 ℃^-4To 1 × 10^-2mmHg pyrethroid (pyrethid) compound. The specification states that the pyrethroid has a particle size of less than 1 μm, and therefore it is entrained in the form of small particles into the air of smoke generated by burning the mosquito coil and is volatilized by heating. These mosquito coils contain a larger amount of the insecticide component than conventional mosquito coils, and the volatilization rate of the insecticide component can be significantly prevented from being lowered by burning the mosquito coil and carrying away the insecticide particles by the smoke generated by the burning.

Therefore, there is a need for an alternative to mosquito coils that can rapidly release active agents while providing long-term protection without excessive pesticide loading and without the need for long-term smoke generation to entrain pesticide particles into the air.

Disclosure of Invention

In a first aspect, there is provided an insect repellent composition comprising:

vapor-active pyrethroids;

a combustible bulk material; and

a binder;

wherein the vapor active pyrethroid is selected from one or more of the group consisting of meperfluthrin (meperfluthrin), ryanodhrin (renoflluthrin), heptafluthrin (heptafluthrin), and more particularly metofluthrin (mefluthrin), transfluthrin (transfluthrin), and tetramethrin (dimefluthrin), and the vapor active pyrethroid is present in an amount to provide the following release rates:

wherein the pyrethroid is metofluthrin, and the release rate is 0.05 to 0.30 mg/min;

wherein the pyrethroid is transfluthrin with a release rate of 0.15 to 0.45 mg/min;

wherein the pyrethroid is permethrin with a release rate of 0.05 to 0.50 mg/min;

wherein the pyrethroid is meperfluthrin with a release rate of 0.04 to 0.40 mg/min;

wherein the pyrethroid is linaflunine and the release rate is 0.05 to 0.50 mg/min; and

wherein the pyrethroid is heptafluoromethyl ether pyrethroid with a release rate of 0.05 to 0.50 mg/min.

In a second aspect, there is provided a method of preparing an insect repellent composition according to the invention, comprising the steps of:

a) providing a vapor-active pyrethroid;

b) providing a combustible bulk material;

c) providing a binder; and

d) the steam-active pyrethroid, the combustible bulk material and the binder are mixed with the addition of water.

In a third aspect, there is provided an article of manufacture comprising an insect repellent composition according to the present invention.

In a fourth aspect, a kit is provided comprising an article according to the invention and a chassis supporting the article.

In a fifth aspect, there is provided a method of repelling insects, wherein the method involves igniting an insect repellent composition according to the invention to repel insects.

Detailed Description

The present invention relates to insect repellent compositions comprising vapour-active pyrethroids. It further relates to articles comprising the insect repellent composition, and processes for preparing the composition and articles made therefrom. The present invention further relates to a kit comprising such an article and a chassis supporting the article. It still further relates to a method of repelling insects, wherein the method involves igniting an insect repellent composition to repel insects. The compositions of the present invention comprise a combustible bulk material and a binder, and may optionally contain preservatives and excipients or other additives. The vapor active pyrethroid is one or more selected from the group consisting of meperfluthrin, linaflunine, metaflumethrin, and more particularly metofluthrin, transfluthrin, and tetramethrin, and is present in an amount capable of providing the following release rates:

wherein the pyrethroid is metofluthrin, and the release rate is 0.05 to 0.30 mg/min;

wherein the pyrethroid is transfluthrin with a release rate of 0.15 to 0.45 mg/min;

wherein the pyrethroid is permethrin with a release rate of 0.05 to 0.50 mg/min;

wherein the pyrethroid is meperfluthrin with a release rate of 0.04 to 0.40 mg/min;

wherein the pyrethroid is linaflunine and the release rate is 0.05 to 0.50 mg/min; and

wherein the pyrethroid is heptafluoromethyl ether pyrethroid with a release rate of 0.05 to 0.50 mg/min.

As used herein, the term "repelling" or equivalent generally refers to preventing insects from entering or staying at a locus, or if entering the locus, from landing on humans and/or animals. This includes behavioral effects of exposure such as disorganization and disorientation, situations that result in uncoordinated landings on human and/or animal targets, and situations in which they are knocked down or killed.

As used herein, the term "release rate" is the product of the amount of pyrethroid present in the composition and its evaporation rate, divided by the combustion time of the bulk material. One skilled in the art will appreciate that the release rate of each pyrethroid may be different, but the same effect of knocking down the insect may still be achieved as long as the release rate is such that a sufficient amount of the pyrethroid is released into the environment. The present invention achieves effective knockdown without using excess pyrethroid in the composition, and the present inventors have recognized that relatively low concentrations of pyrethroid in flammable bulk materials may be effective in certain circumstances (e.g., indoors or enclosed spaces).

As used herein, the term "evaporation rate" refers to the proportion of pyrethroid present in the composition that is released to the air as a vapor upon combustion of the composition. This will be less than 100% because, for example, some pyrethroids can decompose when the composition is burned.

As used herein, the term "burn time" refers to the time of combustion of an article made from the composition disclosed herein before it is exhausted or reaches a point at which it can no longer support combustion.

In embodiments, the pyrethroid may be metofluthrin and the release rate may be from 0.05 to 0.30 mg/min.

In embodiments, the pyrethroid may be permethrin and the release rate may be from 0.05 to 0.50 mg/min.

In embodiments, the pyrethroid may be transfluthrin and the release rate may be from 0.15 to 0.45 mg/min.

In embodiments, the pyrethroid may be meperfluthrin and the release rate is from 0.04 to 0.40 mg/min.

In embodiments, the pyrethroid may be linaflunine and the release rate is from 0.05 to 0.50 mg/min.

In embodiments, the pyrethroid may be metaflumethrin and the release rate is from 0.05 to 0.50 mg/min.

In embodiments, in the compositions disclosed herein, the metofluthrin may be provided in an amount to achieve a release rate of 0.08 to 0.27 mg/min. In embodiments, transfluthrin may be provided that can achieve a release rate of 0.16 to 0.45 mg/min. In embodiments, transfluthrin may be provided that can achieve a release rate of 0.06 to 0.21 mg/min.

One skilled in the art will be able to determine the appropriate amount of pyrethroid to include in the composition within the above-described ranges of release rates. In embodiments, the metofluthrin may be present in an amount of 0.10 to 5.00% w/w, preferably in an amount of 0.50 to 3.00% w/w, more preferably in an amount of 0.35 to 0.66% w/w. In an embodiment transfluthrin is present in an amount of from 0.1 to 5.00% w/w, preferably from 1.00 to 3.00% w/w, more preferably from 0.56 to 1.00% w/w. In embodiments, the transfluthrin may be present in an amount of from 0 to 5.00% w/w, preferably in an amount of from 1.00 to 3.00% w/w, more preferably in an amount of from 0.24 to 1.10% w/w.

The pyrethroid may be provided in any physical form. In embodiments, the pyrethroid may be provided as the compound itself. The compounds may be in solid, semi-solid or liquid form.

Typically, when the compound itself is provided, it may be designated as "technical grade". In an alternative embodiment, the pyrethroid may be provided in the form of an emulsion concentrate (emulsifiable concentrate). In yet a further embodiment, the pyrethroid may be provided in the form of a microemulsion.

Any suitable combustible bulk material may be used. In embodiments, the combustible bulk material may be in the form of a powder of one or more substances selected from the group consisting of wood, sawdust, paper, cardboard, coconut shell, flour made from leaves or nut shells other than coconut shells, jute, bagasse, rice hulls, tea leaves, coffee grounds, charcoal, and pyrethrum grounds.

In embodiments, the combustible bulk material may be one or more selected from the group consisting of wood flour, coconut shell flour, charcoal powder, and pyrethrum slag.

One skilled in the art will be able to determine the appropriate amount of combustible bulk material to include in the composition. The amount of combustible bulk material will be influenced by the flammability and desired burn time of the selected material, as well as the nature of the other components in the composition. In embodiments, the combustible bulk material may be provided in an amount of from 60 to 95% w/w, preferably from 70 to 90% w/w, more preferably from 75 to 85% w/w.

In embodiments, the binder may be selected from one or more materials selected from cedar wood flour (Josspowder), α -starch, Makko flour, balsa flour (tabu powder), carboxymethyl cellulose, guar gum, tapioca starch, tamarind starch, and tamarind kernel powder.

In embodiments, the binder may be selected from one or more materials selected from cedar wood flour, α -starch, Makko flour, incense flour, carboxymethyl cellulose, and guar gum.

In embodiments, the binder may be cedar wood flour and/or α -starch, in embodiments, the ratio of cedar wood flour to α -starch is 4: 1 to 6: 1.

One skilled in the art will be able to determine the appropriate amount of binder to include in the composition. The amount of binder will be affected by the bond strength of the binder, as well as the properties of the other components in the composition. In embodiments, the binder may be provided in an amount of 5 to 40% w/w, preferably 10 to 30% w/w, more preferably 15 to 20% w/w.

In embodiments, the insect repellent composition may further comprise a preservative. For example, the preservative may be selected from one or more materials selected from sodium dehydroacetate, potassium sorbate, and sodium benzoate (e.g., sodium dehydroacetate and sodium benzoate, such as sodium dehydroacetate).

One skilled in the art will be able to determine the appropriate amount of preservative to include in the composition. The function of the preservative is to prevent the growth of mold and microorganisms that may affect the performance or appearance of the article comprising the composition. The amount of preservative will be influenced by the desired shelf life, as well as the nature of the other components in the composition. The preservative may be provided in an amount of 0 to 5% w/w, preferably 0.05 to 3% w/w, more preferably 0.1 to 1% w/w.

In embodiments, the insect repellent composition further comprises other additives or excipients. Other additives include, but are not limited to, emulsifiers, accelerators or oxygen donors for fuels, flame retardants, preservatives, colorants, and fragrances. These may be incorporated into the composition or, in some cases, may be applied as an overcoat to an article formed from the composition.

The colorant enables the article containing the composition to be colored for aesthetic reasons. In embodiments, the colorant may be present in an amount of 0 to 5% w/w, more preferably 0.1 to 0.5% w/w. Suitable colorants include, but are not limited to, malachite green, acid red, and rhodamine B. The presence of the perfume in the article is such as to provide a consumer-friendly odour when the article is burnt. In embodiments, the perfume may be present in the article in an amount of from 0 to 1% w/w, more specifically from 0.1 to 0.5% w/w. Suitable fragrances include, but are not limited to, jasmine or other flower oils or synthetic forms thereof. Cedarwood flour can also be used as a fragrance. The perfume is typically introduced to the surface of the article by impregnation after the article has been formed.

Emulsifiers may be present in the composition. The emulsifier may be combined with the pyrethroid before adding it to the composition, or the emulsifier and pyrethroid may be added separately. In a particularly advantageous embodiment, the emulsifier may be incorporated into the composition by using an Emulsion Concentrate (EC) comprising a solution of the pyrethroid in an organic solvent and at least one emulsifier. Typically, the emulsifier may be present in the EC in an amount of from 5 to 25% w/w, preferably from 10 to 20% w/w. A range of emulsifiers may be used including, but not limited to, any one or combination of anionic, cationic, amphoteric, nonionic and polymeric surfactants. Solvents typically used in EC formulations include hydrocarbon fluids such as dearomatized hydrocarbon fluids, isoalkane fluids and aromatic fluids.

The oxygen donor or promoter, if present, acts by increasing the rate at which the substrate burns. The oxygen donor or enhancer may be present in an amount of 0 to 5% w/w. Suitable promoters or oxygen donors for use in fuels include, but are not limited to, potassium nitrate and lead acetate. Flame retardants, if present, serve to reduce the rate at which the substrate burns. The flame retardant may be present in an amount of 0 to 5% w/w. Suitable flame retardants include, but are not limited to, potassium carbonate, boric acid, and talc.

In embodiments, the composition may be made from:

a vapour active pyrethroid selected from the group consisting of metofluthrin and permethrin, either alone or in combination, wherein the pyrethroid may be present in an amount of from 0.2 to 1.0% w/w; both metofluthrin and tetramethrin are contemplated;

a combustible bulk material which may be one or more of the group consisting of wood flour, coconut shell flour, charcoal powder, and pyrethrum slag, and which may be present in an amount of from 70 to 90% w/w;

a binder, which may be cedarwood flour and α -starch, wherein the w/w ratio of cedarwood flour to α -starch is 4: 1 to 6: 1;

a preservative, which may be sodium dehydroacetate, which may be present in an amount of from 0.1 to 0.5% w/w; and

excipients and/or additives, which may be present in an amount of 0.5 to 5% w/w.

In an embodiment, a 1.3 to 1.5g dosage form of a composition containing at least 0.25% w/w of metofluthrin and/or tetramethrin is provided. Such compositions are capable of testing at 30m when tested using Culex quinquefasciatus in a free flight test conducted immediately after the composition has substantially completely pyrolyzed³Providing a KT of 7.0 to 10 minutes in the space of (1)₅₀. Under the same conditions 8 hoursAfter the time, the composition further provides KT for 21 to 60 minutes₅₀. Typically, the dosage forms disclosed herein are capable of providing KT for 7.0 minutes to 8.5 minutes after substantially complete exhaustion of the composition₅₀And after 8 hours provides KT for 22 to 33 minutes₅₀。

In embodiments, the composition may further comprise water. Water is typically added to facilitate mixing and shaping of the composition. Typically, once the composition is formed, the water will be removed by drying, although some residual water may remain in the composition and article after forming.

In addition, meperfluthrin, linafluvalinate, metaflumethrin, and transfluthrin may also be used in compositions similar to those outlined above for metofluthrin and transfluthrin. In these compositions, meperfluthrin, linafluthrin, heptafluthrin, and transfluthrin may be present alone or in combination with one or more other active agents mentioned herein, including metofluthrin and transfluthrin.

One skilled in the art will appreciate that the compositions of the present invention can be prepared in a variety of ways and then incorporated into an article. Typically, the combustible bulk material and binder are ground into powder form, combined, and added to water containing the pyrethroid and other materials such as dyes, perfumes, binders, and preservatives. The insect repellent composition so produced is in the form of a mass (dough) and may be formed into an article.

The article may be any article including a coil or rod in conventional form, but may also include other configurations. For example, the composition may be provided in a form that is contained within a vial or container and combusted therein. Such vials or containers may be partially open to the atmosphere. For example, it may have an opening that exposes the insect repellent composition, or the insect repellent composition may be located in a chamber within the article, the chamber being vented so that evaporated pyrethroid can be introduced into the air.

It will be appreciated that the article may take the form of a coil or rod. The coil may be formed in a planar circular, hexagonal or other spiral shape by a process involving rolling or pressing a thin sheet of the dough formed in the above process to a uniform thickness, followed by cutting out the coil and baking to remove moisture. The coated rods can be prepared by coating thin wooden rods with the clusters formed in the above process.

Alternatively, the dough formed in the above process may be shaped using molding or other forming methods (e.g., vacuum forming).

In embodiments, the insect repellent composition is molded into an article. In embodiments, the base is molded into the article. Alternatively, a chassis may be provided with the article for insertion therein prior to use. For example, a small hole may be introduced or formed in the article and this may be used to locate the article on an upstanding pin which forms part of a stand for the article. The support may also form a dish or tray for collecting the ashes of the combustion products.

The molded article according to the present invention may be formed into any suitable shape. The article may be helical or may be formed as a rod, disc, cylinder, prism, sphere, pyramid or cone. The pyramid will have an n-sided polygonal base, where n is 3, 4 or more, such as 3 to 8, preferably 3 to 6, and typically 3 (i.e., a triangular base pyramid) or (i.e., a square base pyramid). The prism will have a polygonal base with n bases, a second base which translationally replicates the base, and n further faces connecting the respective sides of the two bases, where n is 3, 4 or more, for example 3 to 12, preferably 4 to 8, and typically 4 (i.e. a cube or rectangular prism), 6 or 8. The article may be truncated, such as a truncated cone or pyramid. The article may be of any shape as long as it can be ignited and maintained in a configuration that allows the combustion to continue for a desired time. Those skilled in the art will appreciate that certain shapes are readily molded and that the molding process may specify shapes that deviate from the general description. For example, the molding process may specify forming a groove (indexing) in the article to receive a support member during the molding process or to facilitate demolding. For example, if the article is shaped as a generally conical or generally pyramidal pyramid, grooves may also be provided to facilitate stacking of the molded articles. Typically, a recess may be provided in the base, but if desired, a depression (depression), indentation, dimple or opening may also be formed in the upper surface or side.

Those skilled in the art will appreciate that some shapes may require support to ensure combustion is sustained, while others, such as cones or cylinders, are self-supporting and therefore can burn without tipping, provided they are placed on surfaces that will not ignite. The shape of the article may be adjusted, for example by adding a flange to increase the area of contact with the support surface to make it more stable. The shape may also be adapted for other purposes, for example by introducing ear wings (tabs) to facilitate handling. The article may include grooves on any surface or may be patterned in any manner. The article may be formed from two or more pieces joined together in any suitable manner.

In embodiments, the molded article may be self-supporting.

In embodiments, the molded article may be substantially conical. It will be appreciated that the substantially conical article may be truncated and may contain grooves in the upper surface (if truncated) or the base or both, and may include other structural elements as described above.

Typically, the weight of the molded article according to the invention is from 0.5 to 5.0g, preferably from 0.8 to 3.0g, more preferably from 1.0 to 2.0 g. The weight is affected by the generally desired burn time. In embodiments, it is desirable for the molded article to burn for 10 to 60 minutes, preferably 15 to 40 minutes, and most preferably 20 to 30 minutes. In a particularly advantageous embodiment, the invention provides a small and fast burning product to provide fast and long term protection against insects (e.g. against mosquitoes). A relatively small cone will burn faster than a larger cone formulated in the same manner. Smaller cones will give faster protection against insects than larger cones, although the protection time is somewhat shorter. The burn time may also be affected by the formulation of the cone. For example, the addition of a promoter will increase burn time. The choice of combustible bulk material can also affect the burn time. Thus, these parameters are selected to achieve a burn time that provides an appropriate guard time. When immediate protection is more important, a shorter burn time is selected, and when the duration of protection is emphasized, a longer burn time is selected.

The weight of the molded article is also affected by the form in which the pyrethroid is provided. While not wishing to be bound by theory, when the pyrethroid is provided in the form of an emulsion concentrate, it is believed that the surfactant and/or organic solvent in the emulsion concentrate is present in an amount sufficient to impart an oily texture to the insect repellent composition, making it difficult to mold. However, this can be addressed by increasing the size of the product, which in turn allows it to be molded into a self-supporting shape, such as the desired conical shape.

In embodiments, articles comprising compositions in which an emulsifier is present, such as compositions in which the pyrethroid is provided in the form of a concentrated emulsion or microemulsion, may be formed into self-supporting shapes, such as cones.

The amount of pyrethroid in each molded article may be selected to achieve a desired release rate. This will be determined more or less by the dimensions of the moulded article. One skilled in the art can adjust the components of the composition and the size and shape of the molded article to achieve a predetermined burn time to achieve release of the pyrethroid at a desired rate.

The invention also provides a kit comprising an article comprising an insect repellent composition and a base for supporting the article.

In embodiments, the article may be somewhat loose (frangible), and the chassis may be adapted for insertion into the article. In particular, the chassis typically includes a portion adapted to pass through the article and a portion for supporting the article once the article is secured to the chassis. However, the chassis may likewise contain support members for supporting the article without passing through it.

In one configuration, the article may include an aperture, wherein the base is adapted to engage with the aperture. In an alternative or additional configuration, the support may comprise a dish or tray for collecting ash of the burned product.

The kit may further comprise instructions for use.

The method of the present invention involves igniting the insect repellent composition to repel insects. Generally, the method involves igniting one or more articles containing a composition according to the present invention.

One skilled in the art will appreciate that because pyrethroids are insecticides, it is possible to kill the insects. It will be further understood by those skilled in the art that knocking down or killing the insects acts to repel the insects, thus protecting people in the location protected by the combustion article or articles of the present invention from insect bites. Those skilled in the art will also appreciate that exposure has behavioral effects on the insect, such as confusion and disorientation, resulting in an uncoordinated landing on human and/or animal targets, and that this also serves the purpose of repelling the insect.

In embodiments, the insect repellent composition can be ignited within the enclosed space. In particular, the insect repellent composition may be ignited indoors, for example, when an occupant sleeps, in a bedroom to repel insects.

The number and spacing of molded articles according to the present invention is determined by a number of factors. If used indoors, the size and shape of the room will affect the number of said articles to be placed in the respective room. If used in partially open spaces, the size and shape of the space will affect the number of articles to be placed in each space. This will also be influenced by, for example, the degree of space confinement and whether there is wind. The size of the molded article and its pyrethroid content will also affect the number of said articles to be placed in the respective room or space. Typically, the moulded article according to the invention may provide ≦ 12.0m for the space in the closed room²This is a typical room size.

The compositions of the present invention are active against a number of insects, particularly flying insects. In an embodiment, the insect is one or more selected from the group consisting of a mosquito, midge, sand fly, black fly, house fly, jungle fly, hairy mosquito, horse fly, bee, wasp, ant, cockroach, leech, tick and mite.

In embodiments, the insect is a mosquito.

Those skilled in the art will appreciate that insects in some places have become resistant to insecticides commonly used in those areas.

Those skilled in the art will appreciate that the compositions of the present invention, which provide long term protection, may be particularly useful in situations where it is necessary to minimize or even avoid exposure to mosquitoes.