Title of Invention

"A SYNERGISTIC COMPOSITION,USEFUL AS AN INSECT REPELLENT"

Abstract

A synergistic composition comprising of dimethyl phthalate in the range of 70 to 75 wt %; allyl sulphate in the range of 10 to 15 wt %; citronella oil in the range of 5 to 10 wt %; neem oil in the range of 5 to 10 wt % and eucalyptus oil in the range of 2 to 5 wt %, which is an effective insect repellent. This composition can be used in combating menace caused by insects, especially mosquitoes, by spraying in different doses on grass, shrubs and trees. Typical sites for use of this composition can be in the yard around one's home or apartment, on a golf course, around a race track, in campground, in a park, on a basket ball or foot ball field and the like.

Full Text

The present invention relates to a synergistic composition, useful as an insect repellent. The present invention particularly relates to a synergistic composition consisting of dimethyl phthalate, allyl sulphate, citronella oil, neem oil, and eucalyptus oil. The synergistic composition of the present invention can be used in combating menace caused by insects, especially mosquitoes, by spraying in different doses on grass, shrubs and trees. Typical sites for use of this synergistic composition can be in the yard around one's home or apartment, on a golf course, around a race track, in campground, in a park, on a basket ball or foot ball field and the like. A search of prior art literature and patent databases reveals that a number of insect repellents have been developed hitherto. For example, N,N-dimethyl mtoluamide has been practically used as mosquito repellent. Camphor, naphthalene and p-dichlorobenzene have been practically used for repelling insects which attack clothing. Although not practically used yet, isoboldine is known to be effective against Prodenia litura, demissine to be effective against Scolytus multistriatus. 4-Methylphenol and 4-ethylphenol were reported to be effective as warning pheromones against Blattella. Also, G. Kajimoto et al have reported about repellency of some antioxidants for foods, hydroquinone, BHA (mixture of 2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole) and BHT (2-6-ditert-butyl-4-methylphenol) against fly's laver and cockroach (Nutrition and Food 14, 378-383 (1962)). The most prominent insect repellent in use today is N,N'-diethyl toluamide, commonly known as DEET. Other volatile insect repellents are known including ethyl hexanediol; 2-(octylthio)ethanol; dimethyl phthalate; di-n-propyl-2,5-pyridine dicarboxylate; 1,5a,6,9,9a, 9b-hexahydro-4a(4b)-dibenzofuran carboxaldehyde; citronellal; citronellol; geraniol; nerol; and linalool. The formulation of such insect repellents is particularly problematic due to the greasy feel of many of the repellents and especially the effect of DEET in staining clothing, crazing plastics and washing away in humid or rainy weather or when the person using the repellent is participating in water sports such as swimming or fishing. In addition, the lack of retention of insect repellents due to the action of water is also affected by the individual wearer's sweating. The evaporation of the insect repellent is directly related to the ambient temperature and wind velocity. Approximately 50% of a topically applied dose is absorbed in six hours with peak plasma levels being reached in 1 hour (Lurie et al, Pharmacokinetics of insect repellent N,N-diethyl toluamide. Med. Parazitol., 47, 72, 1979). Mehr et al, (Laboratory Evaluation of Controlled-Release Insect Repellent Formulations, J. Am. Mosq. Control Assoc., 1,143, 1985) evaluated a number of controlled release formulations of microencapsulated DEET and hydrophilic vinyl polymers such as polyvinylpyrrolidone. The polyvinylpyrrolidone formula was no better than unformulated DEET in repelling mosquitoes. Reifenrath et al, (Evaporation and Skin penetration characteristics of mosquito repellent formulations. J. Am. Mosq. Control Assoc., 5, 45 1989) tested silicone polymers, acrylate polymers, fatty acids and mixtures of repellents and evaluated evaporation and skin penetration. No differences in evaporation and skin penetration was found between formulations containing the polymers and unformulated DEET or with a mixture of dimethyl phthalate and DEET. Reifenrath et al, (In vitro skin evaporation and penetration characteristics of mosquito repellents. J. Pharm. Sci. 71, 1014, 1982) showed that the duration of repellent efficacy on man correlated with the time that vapor levels at the surface of the skin exceeded the minimum effective evaporation rates in-vitro. U.S. Pat No. 4,474,081 discloses the use of maleic anhydride/alpha olefin polymers and terpolymers to provide slow release of contact insect repellents when applied to the surface of the skin. Chemical Abstracts 110, 207847s (1989), discloses mosquito repellent compositions which have an active agent and an oil-soluble, water insoluble acrylate polymer comprising acrylic acid, stearyl methacrylate and isooctylacrylate. Reference may be made to US Patent No. 5,733,552, wherein mosquitoes are discouraged from occupying a grassy recreational area by spraying dilute garlic juice on grass, shrubs and trees. Surprisingly, this treatment repels mosquitoes. More surprisingly, mosquitoes are repelled for many months. For reasons not wholly understood, mosquitoes are repelled by some component of garlic juice, which may not be the odoriferous compounds. The equivalent of at least about 0.04 gallons of full strength garlic juice per acre is applied. Preferably, the garlic juice is applied in a concentration in the range of 0.04-0.5 gallons of full strength garlic juice per acre and in a strength of 1/2-5% garlic juice. In U.S. Patent Nos. 4,455,304; 4,876,090 and 5,429,817, use of garlic products as repellents for insects and birds is disclosed. Garlic juice has been sold to farmers and sprayed on field crops to control plant eating insects. It is known that dilute garlic oil is fatal to mosquito larvae. In parts of Africa, people eat garlic in the belief that the odor of garlic exuded through the skin acts as a repellant preventing Anopheles vectors from biting. It has been demonstrated that garlic fed to guinea pigs has a repellant effect on Anopheles Stephens! but not Aedes aegypti mosquitoes. Garlic juice is obtained by pressing garlic cloves. Generally, commercially available insect repellent compositions comprise an insect repellent compound in a carrier. The cost of the repellent composition is based, to a large extent, upon the cost of the relative amount of repellent compound included therein. Accordingly, any reduction of the relative amount of repellent compound in the carrier while still achieving a strong insect repellent activity will result in a relatively less expensive and desirable commercial product. Further, relatively high concentrations of Deet may give rise to allergic or toxic reactions in some individuals, as it is well known that different individuals may exhibit significantly different allergic reactions to a given substance. Also, at a certain concentration of DEET, a particularly sensitive individual may begin to exhibit signs of allergic reaction, whereas the same individual may not exhibit such a sensitivity when exposed to a second composition which includes a lesser amount of DEET. Moreover, the odor or oily nature of DEET may become undesirable to some individuals at relatively high concentrations. Repellents may be in the form of gases (olfactory), liquids, or solids (gustatory). Some wellknown insect repellents include: benzil, benzyl benzoate; 2,3,4,5-bis(butyl-2-ene) tetrahydrofurfural (MGK Repellent 11); butoxypolypropylene glycol; Nbutylacetanilide; normal-butyl-6,6-dimethyl-5,6-dihydro-1,4,pyrone-2-carboxylate (Indalone); dibutyl adipate; dibutyl phthalate; di-normal-butyl succinate (Tabatrex); N,N-diethyl-meta-toluamide (also known as Delphone, Detamide, Autan, or, more simply, Deet); dimethyl carbate (cis-bicycol-[2.2.1]-5~heptene- 2,3-dicarboxylate); dtmethyl-phthalate; 2-ethyl-2-butyl-1,3-propanediol; 2-ethyl- 1,3-hexanediol (Rutgers 612); di-normal-propyl isocinchomeronate (MGK Repellent 326); 2-phenylcyclohexanol; and normal-propyl N,N-diethylsuccinmate. Standard repellents for mosquitoes, ticks, and the like are citronella oil, dimethyl phthalate, normal-butylmesityl oxide oxalate and 2-ethyl hexanediol-1,3. See Kirk-Othmer Encyclopedia of Chemical Technology, Second Edition, Volume 11, pps. 724-728; and The Condensed Chemical Dictionary, Eighth Edition, Page 756. Reference may be made to U.S. Patent No. 3,590,118, wherein a composition has been described which incorporates known chemical repellents and a water soluble terpolymer resin in a solution which forms a film when applied to skin. The repellent is slowly released to the environment by diffusion and the composition has an effective life longer than that of the repellent agent alone. Effectiveness of up to 24 hours in a temperate climate has been observed. However, the film is stiff which can result in flaking of the film and loss of repellent qualities. Reference may be made to U.S. Patent No. 4,477,467, which describes an insect repellent composition containing DEET as the active agent and an aromatic proton donor as carrier. The carrier can be: (a) monocyclic aromatic with substituted hydroxyl or carbonyl groups or both; and (b) polycyclic aromatic with substituted hydroxyl or carbonyl groups or both. This repellent composition is said to have a longer lasting effect due to increased resistance to absorption through the skin by forming a complex. Reference may be made to U.S. Patent No. 3,966,902, which describes a composition comprising an effective amount of an active ingredient such as a medicinal agent, a disinfectant, a pesticide, an insect repellent or a cosmetic agent in a carrier polymer of a monomer having hydrophilic functional groups containing aluminum, zinc or zirconium bound in complex form. The monomers can be hydroxyl alkyl esters of alpha-beta-unsaturated carboxylic acids (2- hydroxyethylacrylate or methacrylate). These monomers can be reacted with aluminum salts to form complexes. Reference may be made to U.S. Patent No. 4,304,591, which describes a waterinsoluble hydrophilic gel comprising a hydrophilic polymer of mono-olefinic monomers cross-linked with a major amount of a diolefinic non-hydrophilic monomer for use as a carrier for medicaments, pesticides, and fragrances for controlled release. Reference may be made to U.S. Patent No. 4,335,104, which describes a multipurpose anhydrous cosmetic composition which comprises a water insoluble surfactant in combination with active chemical agents. The product has increased and/or prolonged activity in topical applications to skin. Reference may be made to U.S. Patent No. 4,303,675, that describes a mosquito repellent which has a persistent action and is water soluble. The active agent consists of 2,5-dimethyl-2,5-hexanediol and is formulated with an inert carrier in the form of a cream, lotion, spray, soaking agents for towels or a thermal diffusion tabloid. Currently available mosquito repellents do provide relief from mosquitoes but have certain drawbacks, as detailed above, and hence are tolerated only by people motivated to coexist with mosquitoes. Thus, most people opt for indoor entertainment during the mosquito season for want of an effective, unobjectionable repellent. The main object of the present invention is to provide a synergistic composition, useful as an insect repellent, which obviates the drawbacks of the hitherto known prior art, as detailed above. Another object of the present invention is to provide a synergistic insect repellent composition which is cosmetically acceptable and effective in-vivo over long periods of time. Yet another object of the present invention is to provide a synergistic insect repellent composition which is cost effective. Still another object of the present invention is to provide a synergistic insect repellent composition which is eco-friendly. The present invention provides a synergistic composition essentially consisting of dimethyl phthalate, allyl sulphate, citronella oil, neem oil, and eucalyptus oil, which is useful as an effective insect repellent. Accordingly, the present invention provides a synergistic composition, useful as an insect repellent, which comprises: a) dimethyl phthalate in the range of 70 to 75 wt %; b) allyl sulphate in the range of 10 to 15 wt %; c) citronella oil in the range of 5 to 10 wt %; d) neem oil in the range of 5 to 10 wt % and eucalyptus oil in the range of 0 to 5 wt %; optionally along with pharmaceutically acceptable excepients. In an embodiment of the present invention the dimethyl phthalate is such as that obtained commercially. In another embodiment of the present invention the allyl sulphate is such as that obtained commercially. In yet another embodiment of the present invention allyl sulphate is obtained from garlic. In still another embodiment of the present invention the allyl sulphate is prepared by crushing garlic cloves in a mixer with adequate amount of water and distilling the resultant juice. In still yet another embodiment of the present invention the citronella oil is such as that obtained commercially. In a further embodiment of the present invention the neem oil is such as that obtained commercially. In a still further embodiment of the present invention the eucalyptus oil is such as that obtained commercially. In another embodiment of the present invention traces of perfumes and colours are added. The composition of the present invention essentially consisting of dimethyl phthalate, allyl sulphate, citronella oil, neem oil, and eucalyptus oil, is not a mere admixture but a synergistic mixture having properties which are distinct and are not a mere agglomeration of the properties of the individual ingredients. Further, there is no chemical reaction involved. The synergistic composition of the present invention essentially consists of dimethyl phthalate, allyl sulphate, citronella oil, neem oil, and eucalyptus oil. The dimethyl phthalate which forms an essential ingredient of the synergistic composition of the present invention can be obtained by a method as described and claimed in our co-pending patent application no. 0213/DEL/2003. In our co-pending patent application no. 0213/DEL/2003 we have described and claimed a method of producing dimethyl phthalate from naphthalene based chemicals, particularly phthalic anhydride, which is a coal tar bye product, using dimethyl sulphate as a promoter. The novelty of the present invention is in providing a composition which has effective insect repellent properties. The above said novelty has been achieved by the non-obvious inventive step of providing a synergistic composition which essentially consists of 70 to 75 wt % dimethyl phthalate; 10 to 15 wt % allyl sulphate; 5 to 10 wt % citronella oil; 5 to 10 wt % neem and 0 to 5 wt % eucalyptus oil, which is useful as an insect repellant. The following examples are given by way of illustration of the present invention and should not be construed to limit the scope of the present invention. Example-1 This composition contains commercial grade dimethyl phthalate, allyl sulpahte, citronella oil and neem oil. Traces of colour and perfume were added to improve the outlook of the composition and to remove any possible smell of allyl sulphide. (Table Removed) Traces The efficiency of the composition was tested on bushes infested with mosquitoes and found to be excellent. Example-2 This composition contains commercial grade dimethyl phthalate, allyl sulpahte, citronella oil and neem oil. Traces of colour and perfume were added to improve the outlook of the composition and to remove any possible smell of allyl sulphide. (Table Removed) traces The efficiency of the composition was excellent when sprayed on bushes and plants adjacent to courtyards of houses. Example-3 This composition contains commercial grade dimethyl phthalate, allyl sulpahte, citronella oil and neem oil. Traces of colour and perfume were added to improve the outlook of the composition and to remove any possible smell of allyl sulphide. Dimethyl Phthalate (Table Removed) traces The efficiency of the composition was excellent when sprayed in gardens. Example-4 This composition contains commercial grade dimethyl phthalate, allyl sulpahte, citronella oil and neem oil. Traces of colour and perfume were added to improve the outlook of the composition and to remove any possible smell of allyl sulphide. Dimethyl Phthalate (Table Removed) traces The efficiency of the composition was excellent when sprayed near play ground. Example-5 This composition contains commercial grade dimethyl phthalate, allyl sulpahte, citronella oil, neem oil and eucalyptus oil. In this composition, eucalyptus oil along with traces of colour and perfume were added to improve the outlook of the composition and to remove any possible smell of allyl sulphide. Dimethyl Phthalate (Table Removed) The addition of eucalyptus oil provided increased fragrance to the composition. The main advantages of the present invention are: 1. It provides a synergistic insect repellent composition which is cosmetically acceptable and effective in-vivo over long periods of time. 2. It provides a synergistic insect repellent composition which is cost effective. 3. It provides a synergistic insect repellent composition which is eco-friendly. We claim: 1. A synergistic composition, useful as an insect repellent, which comprises: (a) dimethyl phthalate in the range of 70 to 75 wt %; (b) allyl sulphate in the range of 10 to 15 wt %; (c) citronella oil in the range of 10 to 15 wt %; (d) neem oil in the range of 5 to 10 wt %; and (e) eucalyptus oil in the range of 0 to 5 wt %; optionally along with pharmaceutically acceptable excepients. 2. A synergistic composition as claimed in claim 1, wherein the dimethyl phthalate is natural or synthetic in origin. 3. A synergistic composition as claimed in claim 1, wherein the allyl sulphate is natural or synthetic in origin, preferably obtained from garlic. 4. A synergistic composition as claimed in claim 1, wherein the citronella oil is natural or synthetic in origin. 5. A synergistic composition as claimed in claim 1, wherein the neem oil is natural or synthetic in origin. 6. A synergistic composition as claimed in claim 1, wherein the eucalyptus oil is natural or synthetic in origin. 7. A synergistic composition as claimed in claim 1, wherein pharmaceutically acceptable excepients such as traces of perfumes and colours are added. 8. A synergistic composition, useful as an insect repellent, substantially as herein described with reference to the examples.

Documents:

0243-del-2003-abstract.pdf

0243-del-2003-claims.pdf

0243-del-2003-correspondence-others.pdf

0243-del-2003-correspondence-po.pdf

0243-del-2003-description (complete).pdf

0243-del-2003-form-1.pdf

0243-del-2003-form-18.pdf

0243-del-2003-form-2.pdf

0243-del-2003-form-3.pdf

243-del-2003-Abstract-(06-11-2008).pdf

243-del-2003-Claims-(06-11-2008).pdf

243-del-2003-Corresopndence-Others-(06-11-2008).pdf

243-del-2003-Description (Complete)-(06-11-2008).pdf

243-del-2003-Form-1-(06-11-2008).pdf

243-del-2003-Form-3-(06-11-2008).pdf