COMPOSITION AND PROCEDURE FOR THE FIGHT AGAINST TERMITES

The present invention relates to a composition for controlling termites. Further, it relates also to a method for controlling a termite.

As conventional agents for controlling termites, organophosphorus compounds such as chlorpyrifos, or pyrethroids may, for example, be mentioned. However, among them, there are some which are feared to present toxicity against mammals or adverse effects to environment. Under the circumstances, a new agent for controlling a house insect pest is desired.

WO 97/06687 discloses an active substance combination of pyrethroids and insect-development inhibitors for providing long-term pesticidal effects.

WO 95/24997 discloses combinations of active insecticide substances. Synergistic combinations of pesticidally active compounds are known from WO 95/33380.

The present inventors have conducted an extensive research for an agent for controlling a house insect pest. As a result, they have found specifically that a composition as defined by claim 1 provides particularly excellent effects for controlling termites. The present invention has been accomplished on the basis of this discovery.

Namely, the present invention provides a composition for controlling a termite as a house insect pest according to claim 1.

Further, the present invention provides a method for controlling a termite, which comprises applying such a composition to its habitat.

In the present invention, the house insect pest is meant for termite living in a house or around it. The composition of the present invention is useful as a composition for controlling a termite.

Examples of the termite which can be controlled by using the composition of the present invention and the active ingredients, include Mastotermitidae, Termopsidae (Zootermopsis, Archotermopsis, Hodotermopsis, Porotermes and Stolotermes), Kalotermitidae (Kalotermes, Neotermes, Cryptotermes, Incisitermes and Glyptotermes), Hodotermitidae (Hodotermes, Microhodotermes and Anacanthotermes), Rhinotermitidae (Reticulitermes, Heterotermes, Coptotermes and Schedolinotermes), Serritermitidae and Termitidae (Amitermes, Drepanotermes, Hopitalitermes, Trinervitermes, Macrotermes, Odontotermes, Microtermes, Nasutitermes, Pericapritermes and Anoplotermes).

Particularly, types of the termite to be controlled in Japan, include, for example, Reticulitermes speratus, Coptotermes formosanus, Incisitermes minor, Cryptotermes domesticus, Odontotermes formosanus, Neotermeskoshunensis, Glyptotermes satsumensis, Glyptotermes nakajimai, Glyptotermes fuscus, Glyptotermes kodamai, Glyptotermes kushimensis, Hodotermopsis japonica, Coptotermes guangzhoensis, Reticulitermes miyatakei, Reticulitermes flaviceps amamianus, Reticulitermes sp. , Nasutitermes takasagoensis, Pericapriterme nitobei and Sinocapritermes mushae.

The blend ratio for a two component mixture in the present invention, i.e. the blend ratio of active ingredients (i) and (ii) is from 1:1,000 to 1,000:1, preferably from 1:1,000 to 100:1, more preferably from 1:1,000 to 50:1.

The composition of the present invention may be formulated together with adjuvants into various forms such as emulsifiable concentrates, suspension concentrates, wettable powders, water soluble powders, soluble concentrates, floable, water dispersible granules, granules, dusts, aerosols, pastes, poison bait chemicals, gel, formulated sheet, ultra-low volume concentrates and the like, in the same manner as in a case of conventional agricultural chemicals, and may be used as a composition for controlling termites. Such formulations are usually composed of 0.001 to 99 parts by weight, preferably 0.01 to 95 parts by weight, more preferably 0.01 to 80 parts by weight of an active ingredient and 1 to 99.999 parts by weight, preferably 5 to 99.99 parts by weight, more preferably 20 to 99.99 parts by weight of adjuvants. When such formulations are to be actually used, they may be used as they are or after being diluted with suitable diluents such as water to a predetermined concentration.

As the adjuvants, there may be mentioned carriers, emulsifiers, suspending agents, dispersants, extenders, penetrating agents, antifoaming agents, wetting agents, thickeners, preservatives or stabilizers. They may be added as the case requires. The carriers may be classified into solid carriers and liquid carriers. As the solid carriers, there may be mentioned powders of animal and plant origin, such as cellulose (including cellulose derivative), starch, activated carbon, soybean flour, wheat flour, wood powder, fish powder or powdered milk; or mineral powders such as titanium dioxide, talc, kaolin, bentonite, calcium carbonate, zeolite, diatomaceous earth, white carbon, clay or alumina, and the like. As the liquid carriers, there may be mentioned water; alcohols such as isopropyl alcohol or ethylene glycol; ketones such as cyclohexanone or methyl ethyl ketone; ethers such as dioxane or tetrahydrofuran; aliphatic hydrocarbons such as kerosine, light oil or the like; aromatic hydrocarbons such as xylene, trimethylbenzene, tetramethylbenzene, methylnaphthalene or solvent naphtha; halogenated hydrocarbons such as chlorobenzene; acid amides such as dimethylformamide; esters such as glycerine ester of a fatty acid; nitriles such as acetonitrile; sulfur-containing compounds such as dimethyl sulfoxide; and the like.

The composition of the present invention may be applied to the habitat of termites. The habitat of termites, may, for example, be a trail for termites, such as an ant trail, a wood or a soil. The composition of the present invention may be applied to the habitat of termites as formulated into e.g. a poison bait chemical, a dust, a paste or a gel, so that it may be fed or contacted to the whereby the termites can be controlled. Especially, to control termites, it is advisable to adopt ① a method wherein the above-mentioned poison bait chemical is set in a baiting system, or ② a method wherein the above-mentioned dust, paste, gel or the like is applied to an ant trail or is directly coated to the damaged portion.

In an application of the composition of the present invention to an ant trail, it is advisable to destroy a part of the ant trail and apply the composition to the interior of the ant trail. Further, in a case where the composition of the present invention is to be applied to a wood or to the habitat of termites, spray treatment or coating treatment may be employed. When the composition of the present invention formulated into a dust, a paste, a gel or the like, is to be coated to the wood, perforations may be formed for injection treatment through the perforations, as the case requires.

By applying the composition of the present invention as a poison bait chemical to an ant trail or around the ant trail, it is possible to exterminate nests of termites. For example, in a case where an ant trail is present under floor or the like, a part of the ant trail is broken and the composition of the present invention is applied or injected. Otherwise, a poison bait chemical is set around a building by utilizing the nature of termites always looking for a bait, to exterminate them by letting them take in the composition of the present invention. If the poison bait chemical of the composition of the present invention is applied or set, termite workers would eat the bait, continue to invite other termites to the bait to let them continuously die, or termite workers take the bait back to their nests and give the bait to termite soldiers larvae, or termite queen, so that the poison bait chemical containing the composition of the present invention will be distributed in the nest and thereby to destroy the nest. Further, the poison bait chemical may be set in a baiting system such as a bait station, which may be set at or around an ant trail or around a building.

The composition of the present invention may be used for soil treatment in such a manner that a layer of the chemical is formed at the soil surface. More specifically, for example, when a liquid formulation is applied to e.g. under floor soil of a wood building where human can enter, the application may be made by means of a power sprayer, and it is particularly preferred to primarily treat the base portion of a building where an ant trail is likely to be formed. Further, in order to treat under floor soil or the like where human can not enter, such as under floor for bathroom or the front door, a method will be employed wherein a hole is drilled, and the chemical will be injected to soil therethrough. Otherwise, the composition of the present invention may be applied to soil in the form of a granule or a dust.

The composition of the present invention may be formulated into an aerosol containing the above dust. The aerosol usually comprises the above dust and a propellant, and, if necessary, a solvent. Such an aerosol usually contains the dust in an amount of from 0.1 to 10 wt% and the propellant in an amount of from 20 to 90 wt%. Further, the solvent may, for example, be an ester such as isopropyl myristate, isopropyl palmitate, isopropyl decanoate or isopropyl laurate; or an alcohol such as ethanol or isopropyl alcohol.

When the composition of the present invention takes a form of a formulated sheet, it may contain the compound of the active ingredients usually in a concentration of from 0.01 to 20 wt% in the formulated sheet. The formulated sheet may be produced in accordance with a conventional method by having the compounds of the active ingredients supported on a carrier of a sheet shape such as a cellulose sheet. For example, a solution or dispersion containing the compounds of the active ingredients may be coated on a cellulose paper, followed by drying to obtain a formulated sheet. Such a solution or dispersion may be obtained by dissolving or dispersing the compounds of the active ingredients in a suitable solvent, but, if necessary, it can be diluted with a water containing a surfactant or a dispersant.

When the composition of the present invention is to be used for controlling a termite, the dose of the active ingredients may vary depending upon the application method of the composition of the present invention, the formulation and various other conditions, but is usually from 0.1 to 100 g/m², preferably from 0.5 to 20 g/m², in the case of soil treatment, and from 0.01 to 50 g/m², preferably from 0.1 to 5 g/m², in the case of wood treatment. Further, when it is applied as a poison bait chemical, the amount of the active ingredients is at a level of from 0.01 to 10 g per application site.

The composition of the present invention may contain in addition to the compounds of the active ingredients, fungicides of e.g. organosulfur compounds, organophosphorus compounds, organoarsenic compounds or organochlorine compounds; insecticides of e.g. organophosphorus compounds, organochlorine compounds, carbamates or chloronicotinyls, or various anti-biotics or one or more other agents for controlling house insect pests. Particularly, the composition of the present invention may contain insecticides, such as chitin synthesis inhibitors of e.g. organophosphorus compounds, carbamates or chloronicotinyls, or insect growth regulators having sclerotization activities or juvenile hormone mimic activities, or one or more termite-controlling active components, ant-controlling active components or cockroach-controlling active components. Further, an organophosphorus insecticide such as Phoxim, Chlorpyrifos, Pyridaphenthion, Fenitrothion or Propetamphos; a carbamate insecticide such as Fenobucarb or Propoxur; a chloronicotinyl insecticide such as Imidacloprid; or an insecticide such as Sulfuramid or Hydramethylnon, may be particularly suitably incorporated to the composition of the present invention.

The composition of the present invention is excellent in the activities for controlling termites and soil stability, has preventive activities against termites and has lasting activities against termites. Further, such a composition makes it possible to reduce the dose of the chemical and thus makes it possible to reduce health problems or problems of environmental pollution.

Now, some of preferred embodiments of the compositions for controlling termites according to the present invention, will be exemplified. However, the present invention is by no means restricted to such

Benzoylurea compound used as the active ingredient (i) is Chlorfluazuron and/or Hexaflumuron.

Now, the pyrethroid compound and as the active ingredient (ii) is bifenthrin. The pyrethroid compound has various optical isomers, and in the present invention, active optional isomers and their mixture may be used.

Among the above embodiments, the composition for controlling a termite, which is in the form of a poison bait chemical, will be explained. A termite will not die immediately after ingesting the poison bait chemical and will bring the poison bait chemical into the nest. The poison bait chemical brought into the nest will be ingested by or contacted to other termites Consequently, it is possible to kill all of the termites which ingested or were in contact with the poison bait chemical. The poison bait chemical is characterized by having such an effect (an effect of spread).

A conventional quick acting agent of an organic phosphorus type, a pyrethroid type or the like, has a repellent nature and will not be ingested by a house insect pest. Even if it is ingested, the house insect pest ingested it, will die immediately, whereby no effect of spread can be expected. Accordingly, it is common to employ a slow acting conventional agent such as a benzoyl urea compound as the active ingredient for a poison bait chemical. However, if a slow acting active ingredient is employed, although the effect of spread can be obtained, it takes from 2 to 3 months to kill the house insect pests in the entire nest, whereby the damage during the period can not be prevented.

As the base material for a poison bait chemical, various types may be mentioned, but a bait log, fresh pulp or pulp is preferred. As the bait log to be used as the base material, various types may be mentioned, but a bait log of conifer type such as pine, cedar or Hinoki cypress, is preferred. Among them, it is particularly preferred to employ pine. Further, among pines, it is further preferred to employ Japanese larch. Such a conifer type bait log is preferably a dead tree or one obtained by sufficiently boiling it in hot water to decoct components and insect pests in the bait log. The fresh pulp or pulp to be used as the base material is used as a cellulose source which will be a bait for termites. As such pulp, KIMUTAORU (tradename, manufactured by CRECIA Co.) or KITCHENTOWEL (tradename, manufactured by NEPIA Co.) may, for example, be mentioned. The weight ratio of the hydrazone compound or its salt to the base material, is usually from 1:10,000 to 1:4, preferably from 1:1,000 to 1:9.

Among the above embodiments, the composition for controlling a termite which is in the form of a gel, will be explained. The gel may be applied to an ant trail as an ant trail-treating agent or may be coated directly to a damaged portion such as a wood. Otherwise, it may be coated on a bait wood, fresh pulp or pulp to form a poison bait chemical, which will be used as set in a baiting system, and it is particularly effective to use it as coated on a wood damaged by termites. Further, it is most effective to apply it to perforated portions of the wood damaged by termites. The water absorptive polymer to be used for the gel, may be used as the base material or may be contained as an additive in the agent for controlling a termite. Otherwise, it may be used as a carrier for the agent for controlling a termite. The water absorptive polymer may also be one having been swelled by having another component taken into the interior. The water absorptive polymer to be used, is preferably one having a water absorptivity of at least 10 times, preferably at least 100 times, its own weight. One having such a high water absorptivity may, for example, be an isobutylene/maleic anhydride copolymer, a polyacrylate polymer, a starch/polyacrylate polymer, a polyvinyl acetate/polyacrylate polymer, a carboxymethylcellulose polymer or a polyvinyl alcohol polymer. In a case where a water absorptive polymer is used as the base material, its amount is preferably from 0.05 to 10 wt%, more preferably from 0.1 to 5%, in the total weight.

Among the above embodiments, the dust will be explained. The dust may be applied to an ant trail as an ant trail treating agent or used as a poison bait chemical as set in a baiting system. This dust is characterized in that the effect of spread is excellent as compared with conventional dusts. As the solid carrier to be used for this dust, the above-mentioned animal or plant powder, and/or a mineral powder is preferred, and among them, cellulose and/or titanium oxide is preferred. Here, the cellulose may be a commercially available cellulose such as crystalline cellulose; cellulose fiber such as pulp; a cellulose porous body such as cellulose beads; or a cellulose derivative such as carboxymethylcellulose or a cellulose ester.

Among the above embodiments, the soil treating agent will be explained. The soil treating agent is used in the form of an aqueous suspension, a granule, a dust or the like. For example, the aqueous suspension is applied to soil for use.

Preferred embodiments will be given below with respect to the method for controlling a termite by means of the composition for controlling a termite of the present invention, but it should be understood that the present invention is by no means restricted thereto.

1. (1) A method for controlling a termite, which comprises applying the composition of the present invention to the habitat of the termite.
2. (2) The method of (1) wherein the composition of the present invention is fed or contacted to the termite.
3. (3) The method of (1) or (2) wherein the habitat of the termite is soil.
4. (4) The method of (1) wherein the composition for controlling a termite is applied to an ant trail or coated directly to a damaged portion to control termites.
5. (5) The method of (1) wherein the composition for controlling a termite of the present invention in the form of a poison bait chemical, is set in a baiting system.
6. (6) The method of (5) wherein the baiting system is set at or around an ant trail or around a building.
7. (7) The method of (5) or (6), wherein the baiting system is a bait station.
8. (8) The method of (2) wherein the composition of the present invention in the form of a dust, paste or gel, is applied to an ant trail or coated directly to a damaged portion to control termites or ants.
9. (9) The method of (8) wherein the composition of the present invention in the form of a dust, paste or gel, is applied to an ant trail.
10. (10) The method of (8) wherein the composition of the present invention in the form of a dust, paste or gel is directly coated to a damaged portion.

Now, the present invention will be described in further detail with reference to Examples. However, it should be understood that the present invention is by no means restricted to such specific Examples.

A filter paper having a diameter of 80 mm was placed in a plastic Petri dish, and 1 ml of a pesticide solution having a predetermined concentration was dropped thereon. After the treatment, the solvent was sufficiently evaporated, and then, 1 ml of distilled water was impregnated to the treated filter paper, whereupon 15 termite workers and one termite soldier (Reticulitermes speratus) were released. The plastic Petri dish was placed in a container having wet cotton laid over the bottom, and the container was maintained at 25°C for 13 days, whereupon the number of dead termites in the Petri dish was examined, and the mortality was calculated by the following formula. Mortality%=Number of dead termite workers/15termite workers×100

Further, by the Colby's formula, the theoretical value (%) of mortality can be calculated. In a case where the actual mortality (%) is higher than the theoretical value (%), it can be said that the composition of the present invention has a synergistic effect for controlling the house insect pest.

A filter paper having a diameter of 80 mm was placed in a plastic Petri dish, and 1 ml of a pesticide solution having a predetermined concentration was dropped thereon, whereupon 10 termite workers (Coptotermes formosanus) were released, and a cover was put on the Petri dish. This plastic Petri dish was put in a container having wet cotton laid over the bottom and maintained at room temperature of 25°C. On 21 or 28th day after the treatment, the number of dead termites in the Petri dish was examined, and the mortality was calculated in the same manner as Test Example 1. The results are shown in the following table.

According to the present invention, the composition comprising at least two specific compounds as defined by claim 1, as active ingredients, can be used as an agent for controlling termites.