JP2022079611A - Long-acting mosquito-repelling incense - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a long-acting mosquito-repelling incense allowing an insecticidal effect to persist for a long period of time even when burned for a short period of time while reducing irritation during the burning.

SOLUTION: The long-acting mosquito-repelling incense has an insecticidal effect that persists even after being burned and contains at least one insecticidal component selected from the group consisting of metofluthrin, profluthrin, and transfluthrin and a carbide base material having an iodine adsorption capability of 200 mg/g or lower. The amount of the insecticidal component volatilized per unit time during the burning is set to be 0.05 to 15 mg/min, and the burning time is set to fall within 30 minutes.

SELECTED DRAWING: None

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to a persistent mosquito coil whose insecticidal effect is sustained even after burning.

As a product for exterminating flying pests such as mosquitoes, mosquito coils are widely used in which the insecticidal component is volatilized in the space to be treated by smoking. The mosquito coil has a burning time of about 7 to 8 hours according to the bedtime of human beings, and knocks down or kills pests existing in the space to be treated until it burns out, and further, pests from the space. Acts to eliminate or avoid.

By the way, in recent years, due to the improvement of sanitary environment and changes in housing conditions, especially in urban condominiums, housing is becoming more and more sealed, so there is an opportunity for pests such as mosquitoes to invade from outside the building to inside the building. decreasing. For this reason, if mosquitoes and the like in the room are exterminated before going to bed, it is no longer necessary to continuously volatilize the insecticidal component during bedtime as in the case of the conventional mosquito coil. Under such circumstances, an attempt to shorten the burning time of mosquito coils, which has been considered to be basically used continuously for a long time, has been proposed.

For example, there was a mosquito coil using a room temperature volatilizing pyrethroid such as metoflutrin, profluthrin, transfluthrin as an insecticidal component (see, for example, Patent Document 1). In the mosquito coil of Patent Document 1, since the insecticidal component remains in the air for a long time even after burning, the insecticidal effect is maintained for a long time even if the burning time is shortened.

Japanese Unexamined Patent Publication No. 2011-12506

By the way, in mosquito coils, products that reduce odors and irritation caused by insecticidal components, fragrance components, smoke and the like are required. However, Patent Document 1 focuses on volatilizing a required amount of insecticidal component while shortening the burning time, and there is room for study on reducing irritation during burning.

The present invention has been made in view of the above problems, and is a long-lasting mosquito coil that can maintain an insecticidal effect for a long time even if it is burned for a short time while reducing irritation at the time of burning. The purpose is to provide.

The characteristic composition of the persistent mosquito coil according to the present invention for solving the above-mentioned problems is
A long-lasting mosquito coil that has a long-lasting insecticidal effect even after burning.
With at least one insecticidal component selected from the group consisting of metoflutrin, profluthrin, and transfluthrin,
Carbide base material with iodine adsorption capacity of 200 mg / g or less,
Is to be contained.

According to the persistent mosquito coil of this composition, in addition to at least one insecticidal component selected from the group consisting of metoflutrin, profluthrin, and transfluthrin, a carbide base material having an iodine adsorption capacity of 200 mg / g or less is contained. By doing so, the insecticidal component remains in the air for a long time even after burning, and the insecticidal effect can be maintained for a long time. In addition, a carbide base material with an iodine adsorption capacity of 200 mg / g or less can reduce odors and irritation caused by smoke during combustion while preventing the insecticidal component from being excessively decomposed and reducing the insecticidal effect. can.

In the persistent mosquito coil according to the present invention
It is preferable that the amount of volatilization of the insecticidal component at the time of combustion per unit time is set to 0.05 to 15 mg / min.

According to the persistent mosquito coil of this composition, the amount of the insecticidal component volatilized per unit time is within the above range, so that a sufficient amount of the insecticidal component is volatilized in the air even if it is burned for a short time. be able to.

In the persistent mosquito coil according to the present invention
It is preferable that the burning time is set within 30 minutes.

According to the persistent mosquito coil of this configuration, by setting the burning time within 30 minutes, mosquitoes can be controlled only by burning before going to bed, and the product is easy to use.

In the persistent mosquito coil according to the present invention
It is preferable that the duration of the insecticidal effect after burning is set to 8 hours or more.

According to the persistent mosquito coil of this composition, the duration of the insecticidal effect after burning is set to 8 hours or more, so that when used at night, a person will not be bitten by mosquitoes all night. , You can sleep comfortably. Also, if you set the burning time to 30 minutes or less and the duration of the insecticidal effect after burning to 8 hours, the fire of the persistent mosquito coil will be extinguished by the time a person falls asleep, so be worried about the fire. It can be used safely even at night.

In the persistent mosquito coil according to the present invention
When the compounding amount of the insecticidal component is _CI (mg) and the volatilization amount of the insecticidal component when completely burned is V (mg), the following formula (1):
(V / _CI ) × 100 ≧ 40 ・ ・ ・ (1)
It is preferable that it is set to satisfy.

According to the persistent mosquito coil of the present configuration, by satisfying the above formula (1), a sufficient amount of the insecticidal component can be volatilized in the air while suppressing the blending amount of the insecticidal component.

In the persistent mosquito coil according to the present invention
When the compounding amount of the insecticidal component is _CI (mg), the compounding amount of the carbide base material is CB (g), and the iodine adsorption capacity of the carbide base material is _A (mg / g), the following Equation (2):
_CI / (CB x _A ) ≧ 3 × 10 ^-2 ... (2)
It is preferable to satisfy.

According to the long-lasting mosquito coil of this configuration, by satisfying the above formula (2), the insecticidal effect is prolonged after burning while preventing the insecticidal component from being excessively decomposed by the iodine adsorption ability of the carbide base material. An appropriate amount of pesticide component that can be sustained for a long time can be volatilized.

Hereinafter, the persistent mosquito coil of the present invention will be described. However, the present invention is not intended to be limited to the configurations described in the embodiments described below.

[Sustainable mosquito coil]
The persistent mosquito coil of the present invention contains an insecticidal component and a carbide base material. For example, a mixed powder containing the insecticidal component and the carbide base material is kneaded by adding an appropriate amount of water. Is obtained by molding with an extruder, a punching machine, or the like, and then air-drying or heating-drying. As other base materials, a combustion support agent, a bulking agent, a binder and the like can be added to the mixed powder. The insecticidal component may not be directly blended with the mixed powder, but a liquid agent containing the insecticidal component or the like may be sprayed or applied after molding. The size of the persistent mosquito coil is preferably set to a total length of 100 mm or less, a thickness of 7 mm or less, and a weight of 5 g or less, and a total length of 20 mm or more and 90 mm or less, a thickness of 2 mm or more and 5 mm or less, and a weight of 0.2 g or more and 3 g or less. Is more preferable. The shape of the persistent mosquito coil can be appropriately selected from rod-shaped, spiral-shaped, cone-shaped, plate-shaped and the like depending on the purpose of use, but rod-shaped, spiral-shaped and plate-shaped are preferable.

As the insecticidal component, metoflutrin, profluthrin, or transfluthrin, which are pyrethroid-based insecticidal components having volatility at room temperature, are used. If an asymmetric carbon or an optical isomer or a geometric isomer based on a double bond is present in the chemical structure of these pyrethroid insecticidal components, any isomer can be used. These pyrethroid insecticidal components can be used alone or as a mixture of two or more, but preferably contain metoflutrin. Here, having room temperature volatilization means that the vapor pressure at 30 ° C. is 2 × 10 ^-4 to 1 × 10 ⁻² mmHg. Since metoflutrin, profluthrin, and transfluthrin are volatilized at room temperature, they remain in the air for a long time even after burning the persistent mosquito coil, so that the insecticidal effect can be sustained for a long time. be. In addition, metoflutrin, profluthrin, and transfluthrin exert a continuous insecticidal effect even when mosquitoes, which have a habit of stopping on the wall surface, come into contact with each other by partially adhering to the wall surface after volatilization. be able to. In addition, in the present specification, the insecticidal effect shall include, in addition to the effect of lethal or knocking down the pest, the effect of repelling the pest that repels the pest.

The content of the insecticidal component is preferably 0.1 to 5% by weight, more preferably 0.2 to 3% by weight, based on the total weight of the persistent mosquito coil. If the content of the insecticidal component is less than 0.1% by weight, a sufficient insecticidal effect may not be obtained. If the content of the insecticidal component exceeds 5% by weight, the persistent mosquito coil may disappear because the insecticidal component is not a component that directly contributes to combustion.

As the carbide base material, a carbide base material having an iodine adsorption capacity of 200 mg / g or less is used. Specific examples of the charcoal base material include charcoal, bamboo charcoal, vegetable activated carbon, coconut shell charcoal, and plant-derived charcoal base materials such as coffee cake charcoal, as well as carbon black, graphite, acetylene black, and coal. Examples thereof include non-vegetable-derived charcoal base materials such as activated carbon and petroleum-derived activated carbon, and plant-derived charcoal base materials are particularly preferable. The details will be described in Examples described later, but when a carbide base material having an iodine adsorption capacity of 200 mg / g or less is added to the persistent mosquito coil, excessive decomposition of the insecticidal component due to the iodine adsorption capacity of the carbide base material is caused. While preventing it, it is possible to effectively reduce or alleviate the odor and irritation caused by smoke and the like during burning of the persistent mosquito coil. If the iodine adsorption capacity of the carbide base material exceeds 200 mg / g, the insecticidal component may be excessively decomposed and a sufficient insecticidal effect may not be obtained. Further, in the persistent mosquito coil of the present invention, it is possible to mix and use a plurality of types of carbide substrates having different iodine adsorbing abilities so that the iodine adsorbing ability is 200 mg / g or less. The iodine adsorption capacity is measured according to the activated carbon test method specified in JIS K 1474.

The content of the carbide base material is preferably 20 to 80% by weight based on the total weight of the persistent mosquito coil. When the content of the carbide base material is less than 20% by weight, there is a possibility that the odor and irritation caused by smoke and the like during combustion cannot be sufficiently alleviated. If the content of the carbide base material exceeds 80% by weight, the moldability and strength of the durable mosquito coil may not be ensured.

The fuel-supporting agent is compounded to stably burn a long-lasting mosquito coil. The bulking agent is formulated to enhance the formability of the long-lasting mosquito coil. The binder is formulated as a binder that binds and hardens the raw materials. Fuel support agents, bulking agents, and binders are the base materials for persistent mosquito coils. Examples of suitable fuel-supporting agents include wood powder, pyrethrum extract powder, citrus epidermis powder, tea powder, coconut shell powder and the like. These combustion support agents can be used alone or as a mixture of two or more kinds. Examples of suitable bulking agents include diatomaceous earth, talc, clay, kaolin and the like. These bulking agents can be used alone or as a mixture of two or more. Examples of suitable binders include tab flour, starch (α-starch, tapioca flour, etc.), methyl cellulose, carboxymethyl cellulose (CMC) and the like. These binders can be used alone or as a mixture of two or more. The carbide base material, fuel support agent, bulking agent, and binder are the base materials of the persistent mosquito coil, and the content of the base material is 90% by weight or more based on the total weight of the persistent mosquito coil. It is preferable to have.

Mosquito coils are usually given a scent suitable for incense sticks, but recently, various volatile fragrance components may be added for the purpose of obtaining an aroma effect and a relaxing effect. The persistent mosquito coil of the present invention can suppress the odor and irritation caused by smoke during burning regardless of the addition of a fragrance component, and can maintain the insecticidal effect for a long time. Also in the persistent mosquito coil of the present invention, various fragrance components can be added for the purpose of obtaining an aroma effect and a relaxing effect. Examples of fragrance ingredients are galaxolide, muskketone, hexyl cinnamic aldehyde, isoe super, methyl dihydrojasmonate, ethylene brush rate, geraniol, methyl atlasate, hexyl salicylate, tricyclodecenyl acetate, oranger crystal, ambro. Xan, tonalide (6-acetyl-1,1,2,4,4,7-hexamethyltetraline), γ-undecalactone, cashmeran, caron, heliotropin, dihydroindenyl-2,4-dioxane, α -Isomethylionone, indol, methylsedrill ketone, methyl β-naphthylketone, rosephenone, coumarin, vanillin, stylux resinoid, benzylbenzoate, undecanal, benzylsalicylate, ionone, α-ionone, β-ionone , Lilyaldehyde, 3,5-dinitro-2,6-dimethyl-4-t-butylacetophenone, acetylsedrene, 2-cyclohexylidene-2-phenylacetaldehyde, isolongihoranone, cis-3-hexenol, etc. Can be mentioned. These fragrance ingredients can be used alone or as a mixture of two or more. The content of the fragrance component is preferably 0.001 to 5% by weight, more preferably 0.01 to 1% by weight, based on the total weight of the persistent mosquito coil. If the content of the fragrance component is less than 0.001% by weight, it may not be possible to sufficiently produce the fragrance. If the content of the fragrance component exceeds 5% by weight, the odor or irritation may become too strong.

The persistent mosquito coil of the present invention may contain a fungicide, a preservative, a stabilizer, an efficacy enhancer, a deodorant and the like as other components. Examples of the fungicide or preservative include dehydroacetic acid salt, sorbate salt, p-hydroxybenzoate salt and the like. To give an example of a stabilizer, 2,6-di-terriary butyl-4-methylphenol (BHT), 2,2'-methylenebis (4-methyl-6-tertiary butylphenol), 2,2'-methylenebis (4). -Ethyl-6-tertiary butylphenol), 4,4'-butylidenebis (3-methyl-6-tertiary butylphenol), 4,4'-thiobis (3-methyl-6-tertiary butylphenol), 2-tertiary Butyl-6- (3-tertiary butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2,4-di-tertiary butyl phenyl 3,5-di-terriary butyl-4-hydroxy Benzoate and the like can be mentioned. By adding such a stabilizer, not only the stability of the insecticidal component over time during storage but also the stability during smoking is significantly enhanced, and the efficacy and durability of the active ingredient after volatilization are improved. Can also contribute. The amount of the stabilizer added is preferably 0.01 to 0.5 times the amount of the insecticidal component. Examples of the efficacy enhancer include piperonyl butoxide, N- (2-ethylhexyl) -bicyclo [2,2,1] hepta-5-ene-2,3-dicarboxyimide and the like. Further, the persistent mosquito coil may contain a coloring agent such as malachite green and food additives (edible blue No. 1, edible yellow No. 4, edible red No. 106, etc.).

[Burning time]
Conventional mosquito coils control mosquitoes and the like by volatilizing insecticidal components by smoking during combustion, but smoke generation may be avoided when used at bedtime. The persistent mosquito coil of the present invention is easy to use by setting the burning time within an appropriate range because the insecticidal component remains in the air for a long time even after burning and the insecticidal effect can be maintained. Can be improved. The persistent mosquito coil of the present invention preferably has a burning time of 30 minutes or less from ignition to burning out. By setting the burning time to 30 minutes or less, it is possible to control mosquitoes for a long time while sleeping, but it burns persistent mosquito coils before going to bed or immediately after going to bed. After finishing, you can go to bed without worrying about smoke. After burning the persistent mosquito coil, the duration of the insecticidal effect (time during which mosquitoes can be controlled) is preferably 8 hours or more, more preferably 10 hours or more, and most preferably 12 hours or more. By setting the duration of the insecticidal effect after burning to 8 hours or more, for example, when used at night, a person can sleep comfortably all night without being bitten by mosquitoes. Also, if you set the burning time to 30 minutes or less and the duration of the insecticidal effect after burning to 8 hours, the fire of the persistent mosquito coil will be extinguished by the time a person falls asleep, so be worried about the fire. It can be used safely even at night. As described above, the persistent mosquito coil of the present invention is suitable for indoor use because the insecticidal effect lasts for a long time while the burning time is short, and the space is particularly highly airtight. It is suitable for use in. However, the persistent mosquito coil of the present invention can of course be used outdoors.

[Amount of insecticidal component volatilized per unit time]
The persistent mosquito coil of the present invention sets the amount of the insecticidal component volatilized per unit time at the time of combustion within an appropriate range, so that a sufficient amount of the insecticidal component can be in the air even if it is burned for a short time. Can be volatilized. Here, the amount of the insecticidal component volatilized when the persistent mosquito repellent incense is completely burned is determined by completely burning the persistent mosquito repellent incense in the exhaust bell connected to the glass tube filled with silica gel. It is calculated by trapping the insecticidal component volatilized by combustion by sucking the air in the pump and analyzing the trapped insecticidal component by gas chromatography. The amount of volatilization per unit time obtained by dividing the amount of volatilization of the insecticidal component calculated in this way by the burning time is preferably 0.05 to 15 mg / min, and more preferably 0.1 to 10 mg / min. preferable. If the amount of the insecticidal component volatilized per unit time is within the above range, an appropriate amount of the insecticidal component can be volatilized in the air even if the combustion is performed for a short time of 30 minutes or less. Further, if the amount of the insecticidal component volatilized per unit time is within the above range, the odor and irritation caused by smoke during combustion can be reduced even if the iodine adsorption capacity of the carbide base material is 200 mg / g or less. be able to. When the amount of the insecticidal component volatilized per unit time is less than 0.05 mg / min, a sufficient amount of the insecticidal component cannot be vaporized in the air by burning for a short time of 30 minutes or less, and the insecticidal effect is sustained. There is a risk of not doing so. If the amount of the insecticidal component volatilized per unit time exceeds 15 mg / min, there is a risk that the odor and irritation of smoke caused by smoke during combustion cannot be sufficiently alleviated. Furthermore, since the insecticidal component is not a component that directly contributes to burning, the persistent mosquito coil may disappear.

[Maintenance rate of insecticidal components]
In the persistent mosquito coil of the present invention, when the amount of the insecticidal component is _CI (mg) and the amount of the insecticidal component volatilized when completely burned is V (mg), the amount of the insecticidal component volatilized V. The insecticidal component maintenance rate, which is the ratio between the amount of the insecticidal component and the amount of the insecticidal component _CI , is calculated by the following formula (1):
Insecticidal component maintenance rate = (V / _CI ) × 100 ≧ 40 ・ ・ ・ (1)
It is preferable to satisfy. By satisfying the condition of the formula (1), the insecticidal component is not excessively decomposed during the storage and burning of the persistent mosquito coil. A sufficient amount of insecticidal component can be volatilized in the air. If the insecticidal component retention rate is less than 40%, the amount of the insecticidal component required for producing the persistent mosquito coil becomes large, which may be economically disadvantageous. In addition, since the insecticidal component is not a component that directly contributes to combustion, increasing the amount of the insecticidal component may cause the persistent mosquito coil to disappear.

[Insecticidal component / adsorption capacity ratio]
In the mosquito repellent incense, when the amount of the insecticidal component is _CI (mg), the amount of the charcoal base material is C _B (g), and the iodine adsorption capacity of the charcoal base material is A (mg / g). The product of the compounding amount C _B of the charcoal base material and the iodine adsorption capacity A of the charcoal base material indicates the total amount of iodine adsorption of the entire persistent mosquito repellent incense. Here, the insecticidal component / adsorption capacity ratio, which is the ratio of the compounding amount _CI of the insecticidal component to the product of the compounding amount C _B of the carbide base material and the iodine adsorption capacity A of the carbide base material, affects the volatilization amount of the insecticidal component. give. In the persistent mosquito coil of the present invention, the insecticidal component / adsorption capacity ratio is as follows:
Insecticidal component / adsorption capacity ratio = _CI / (CB × _A ) ≧ 3 × 10 ^-2 ... (2)
It is preferable to satisfy. By satisfying the formula (2), the ratio of the insecticidal component decomposed by the iodine adsorption capacity of the carbide base material during storage and combustion of the persistent mosquito coil is sufficient with respect to the blending amount of the insecticidal component at the time of manufacture. It will be small. Therefore, even if some of the insecticidal components are decomposed during storage and burning of the persistent mosquito coil, it is possible to volatilize an appropriate amount of the insecticidal component capable of sustaining the insecticidal effect for a long time after burning. .. When the insecticidal component / adsorption capacity ratio is less than 3 × ^10-2 , it is decomposed by the iodine adsorption capacity of the carbide base material during storage and combustion of the persistent mosquito coil with respect to the amount of the insecticidal component at the time of manufacture. The proportion of insecticidal components to be produced increases, and there is a risk that the insecticidal components that volatilize during combustion will be insufficient.

[Pests to be controlled]
The pests to be controlled by the persistent mosquito repellent incense of the present invention are not particularly limited. , Flies, bees, abs, buoys, mosquitoes, squid and other flying pests, as well as cockroaches such as Aedes albopictus, Aedes albopictus, Aedes albopictus, Aedes albopictus, Aedes albopictus, Aedes albopictus, etc. Aedes albopictus is mentioned, and among these pests, it is particularly effective against Culex and Aedes albopictus.

[Example 1]
A mixed fragrance containing charcoal powder A (50 parts by weight) having an iodine adsorbing ability of 25 mg / g as a charcoal base material, metoflutrin (1.5 parts by weight) as an insecticidal component, galaxoride as a fragrance component, and muskketone (muskketone). 0.8 parts by weight), as a fuel-supporting agent / bulking agent, insecticide chrysanthemum-extracted lees powder (17 parts by weight), wood powder (10.7 parts by weight), diatomaceous soil (3 parts by weight), and sticking. As an agent, α starch (14 parts by weight) and carboxymethyl cellulose (CMC) (3 parts by weight) were mixed, water (90 parts by weight) was added thereto, and the mixture was sufficiently kneaded. The kneaded product was molded into a rod shape by an extruder, and then dried until the water content was about 7 to 10% by weight to prepare a persistent mosquito coil of Example 1. The persistent mosquito coil of Example 1 had an insecticidal component / adsorption capacity ratio of 1.2 and satisfied the above-mentioned formula (2).

When the persistent mosquito coil of Example 1 was used in a room of 10 tatami mats (area 16.7 m ² , height 2.5 m, volume 41.7 m ³ ), it burned out in about 23 minutes, but 12 hours after burning. Various pests such as mosquitoes did not approach. From this, it is considered that a sufficient amount of the insecticidal component remained in the room for 12 hours even after the burning of the persistent mosquito coil of Example 1. In addition, the persistent mosquito coil of Example 1 produced a small amount of smoke during combustion, did not feel a pungent odor, and produced a faint floral scent. This scent provided a feeling of relaxation and was suitable for use in the bedroom.

[Examples 2 to 12]
As the carbide base material, charcoal powder A having an iodine adsorption capacity of 25 mg / g and charcoal powder B having an iodine adsorption capacity of 838 mg / g were used, and the formulation shown in Table 1 was used according to the present invention according to Example 1. Persistent mosquito coils (Examples 2 to 12) having the characteristic composition of the above were prepared. The persistent mosquito coils of Examples 2 to 12 had an insecticidal component / adsorption capacity ratio of 3.1 × ^10-2-2.2 , and all of them satisfied the above-mentioned formula (2). ..

[Comparative Examples 1 to 3]
As the carbide base material, charcoal powder A having an iodine adsorption capacity of 25 mg / g and / or charcoal powder B having an iodine adsorption capacity of 838 mg / g were used, and the formulations shown in Table 2 were formulated according to Example 1. Persistent mosquito coils (Comparative Examples 1 to 3) having no characteristic composition of the present invention were prepared. The persistent mosquito coils of Comparative Examples 1 to 3 are examples in which the iodine adsorption capacity of the carbide base material is larger than that specified in the present invention, and the insecticidal component / adsorption capacity ratio is also 7.2 × 10 ^-3 to 2. It was .2 × ^10-2 , and none of them satisfied the condition of the above-mentioned equation (2).

[Reference example]
A persistent mosquito coil (reference example) was prepared according to Example 1 with the formulation shown in Table 2 without using a carbide base material having an iodine-adsorbing ability.

Each test shown in the following (1) to (4) was carried out using Examples 1 to 12, Comparative Examples 1 to 3, and the persistent mosquito coil of Reference Example.

(1) Stability over time The insecticidal component contained in the persistent mosquito coil after storage at 50 ° C for 1 month was analyzed by gas chromatography, and the content of the insecticidal component after storage for 1 month and the insecticidal component at the time of manufacture. The recovery rate of the insecticidal component was calculated from the blending amount of. Stability over time was determined according to the following criteria.
A: Recovery rate of insecticidal component 95% or more B: Recovery rate of insecticidal component 90% or more, less than 95% C: Recovery rate of insecticidal component less than 90%

(2) Insecticidal component retention rate The insecticidal component volatilized by combustion by completely burning the persistent mosquito coil in the exhaust bell connected to the glass tube filled with silica gel and sucking the air in the exhaust bell with a pump. Was trapped and the trapped insecticidal component was analyzed by gas chromatography to calculate the amount of the insecticidal component volatilized when the persistent mosquito coil was completely burned. Then, the insecticidal component maintenance rate was calculated based on the above-mentioned formula (1) from the calculated volatilization amount and the blending amount of the insecticidal component at the time of production.

(3) Preference By burning a persistent mosquito coil in a glass cylinder with a diameter of 20 cm and a height of 40 cm, 10 panelists gave the highest score of 10 and the lowest score of 1 for stimulant relaxation and scent preference. Evaluated as. As a result of the palatability test by the sensory test, the average value of the scores by 10 panelists was calculated.

(4) Practical insecticidal efficacy test A persistent mosquito coil was burned in the center of a closed 25 m ³ room. Eight hours after burning, 50 adult Culex pipiens were released and exposed for 2 hours, after which all test mosquitoes were recovered. During that time, the adult Culex pipiens that fell and turned over with the passage of time were counted, and the time when 25 adult Culex pipiens fell and turned up was defined as the KT ₅₀ value (rounded to the nearest whole number).

The persistent mosquito coils of Examples 1 to 12, which contain metoflutrin, profluthrin, or transfluthrin as an insecticidal component and contain a carbide base material having an iodine adsorption capacity of 200 mg / g or less, are excellent in stability over time. It was confirmed that the insecticidal component retention rate was 40% or more, and the KT ₅₀ value 12 hours after combustion was 30 minutes or less even if the combustion was performed for a short time within 30 minutes, and an excellent insecticidal effect could be continuously obtained. rice field. The persistent mosquito coils of Examples 1 to 12 have the same or higher stability over time as the reference example not containing a carbide base material having an iodine-adsorbing ability, and have an insecticidal effect 12 hours after burning. It is considered that the iodine adsorption capacity of the carbide base material is suppressed to 200 mg / g or less, so that the excessive decomposition of the insecticidal component by the carbide base material does not occur.

In addition, the persistent mosquito coil of Reference Example was worried about the odor of smoke and the amount of smoke, whereas the persistent mosquito coil of Examples 1 to 12 were all after burning. It had a highly palatable fragrance, was not overfilled with smoke, and was easy to use in actual use with excellent irritation-relieving properties and fragrance palatability. From this, the persistent mosquito coils of Examples 1 to 12 have the effect of reducing the odor and irritation caused by smoke during combustion even if the iodine adsorption capacity of the carbide base material is 200 mg / g or less. It is considered that it can be sufficiently obtained.

Among the persistent mosquito coils of Examples 1 to 12, those having a relatively low amount of volatilization of the insecticidal component per unit time (Examples 4 to 6 and 8) tended to have a slightly reduced efficacy. rice field. Further, in Example 3 in which the amount of volatilization per unit time was 10.2 mg / min, which was extremely large, the burning of the persistent mosquito coil did not continue until the end. Therefore, the amount of the insecticidal component volatilized per unit time is preferably 0.05 to 15 mg / min, more preferably 0.1 to 10 mg / min.

Compared with Example 1, in Example 9, the amount of the insecticidal component and the carbide base material is the same, and only the type of the fragrance component is different, but the insecticidal component retention rate and the KT 50 12 hours after combustion are KT ₅₀ . There was no big difference in the values. Example 10 is different from Example 1 in that the amount of the insecticidal component and the carbide base material is the same and the fragrance component is not mixed, but the insecticidal component retention rate and 12 hours after combustion. There was no big difference in the KT ₅₀ value of. From this, it is considered that the type and blending amount of the fragrance component do not have a great influence on the decomposition of the insecticidal component due to the iodine adsorption ability of the carbide base material.

On the other hand, when metoflutrin is contained as an insecticidal component as in Comparative Examples 1 to 3, but a carbide base material having an iodine adsorption capacity of more than 200 mg / g is contained, the stability of the insecticidal component over time is insufficient. The insecticidal component retention rate was less than 40%, and the KT ₅₀ value 12 hours after combustion was 120 minutes or more, and a sufficient insecticidal effect could not be obtained. It is considered that this is because the iodine adsorption capacity of the carbide base material exceeds 200 mg / g, which causes excessive decomposition of the insecticidal component by the carbide base material. Further, in the persistent mosquito coils of Comparative Examples 1 to 3, it was difficult to perceive the fragrance due to the fragrance component, and the result was that the fragrance tone was altered.

The persistent mosquito coil of the present invention can be used as a household or commercial mosquito coil for controlling pests, and is particularly suitable for mosquitoes such as Culex pipiens, London Underground mosquito, and Aedes albopictus. be.

Claims (3)

A long-lasting mosquito coil that has a long-lasting insecticidal effect even after burning.
Contains at least one insecticidal component selected from the group consisting of metoflutrin, profluthrin, and transfluthrin.
A persistent mosquito coil in which the amount of volatilization of the insecticidal component at the time of burning is set to 0.1 to 15 mg / min. The persistent mosquito coil according to claim 1, wherein the burning time is set to 30 minutes or less. When the compounding amount of the insecticidal component is _CI (mg) and the volatilization amount of the insecticidal component when completely burned is V (mg), the following formula (1):
(V / _CI ) × 100 ≧ 40 ・ ・ ・ (1)
The persistent mosquito coil according to claim 1 or 2, which is set to satisfy the above conditions.