TWI808528B - Sustained mosquito incense - Google Patents

Abstract

The present invention is to provide a persistent mosquito-killing coil which can maintain the insecticidal effect for a long time even if it burns for a short time while reducing the stimulation during burning. The present invention is a persistent mosquito-killing incense stick with continuous insecticidal effect even after burning. It is characterized in that it contains at least one insecticidal component selected from the group consisting of metrin, profluthrin, and bifulin, and a carbide substrate with an iodine adsorption capacity of 200 mg/g or less. The volatilization amount of the insecticidal component per unit time during combustion is set at 0.05-15 mg/min, and the burning time is set within 30 minutes.

Description

Persistent Mosquito Killing Incense

The present invention relates to a persistent mosquito-killing line incense which maintains insecticidal effect even after burning.

As a product for repelling flying pests such as mosquitoes, there are widely used mosquito-killing incense sticks that disperse insecticidal ingredients in the space to be treated by fumigation. Mosquito-killing incense sticks are set to match the bedtime of human beings, and the burning time of one column is set at about 7 to 8 hours. The pests in the space to be treated will be knocked down or killed until they are burned out, and then the pests will be eliminated or avoided from the space.

However, in recent years, due to the improvement of the sanitation environment or changes in housing affairs, especially in the buildings of the Ministry of Metropolis, the sealing of residences is also progressing, reducing the chance of mosquitoes and other pests entering the building from outside the building. Therefore, if the mosquitoes in the room are expelled before going to bed, it is no longer necessary to disperse the insecticidal ingredients continuously during the bedtime, as in the past. Judging from this situation, up to now, long-term continuous use has been considered as the basic mosquito-killing coil, and there is an attempt to shorten the burning time in the proposal.

For example, there are mosquito-killing coils that use room-temperature volatile pyrethrins such as metrin, profluthrin, and bifurin as insecticidal ingredients (for example, refer to Patent Document 1). In the mosquito-killing coil of Patent Document 1, even after burning, the insecticidal component remains in the air for a long time, so even if the burning time is shortened, the insecticidal effect can be maintained for a long time. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2011-12056

[Problem to be solved by the invention]

However, in mosquito repellent coils, there is a search for a product that reduces odor or irritation caused by insecticidal components or fragrance components, thereby reducing smoke and the like. However, Patent Document 1 has focused on reducing the burning time while dispersing the necessary amount of insecticidal components, and there is still room for research on reducing the irritation during burning.

The present invention is made in view of the above-mentioned problems, and aims to provide a persistent mosquito-killing coil that can maintain the insecticidal effect for a long time even if it burns for a short time while reducing the irritation during burning. [Means to solve the problem]

The characteristic composition of the persistent mosquito-killing coil of the present invention for solving the above-mentioned problems is that it is a persistent mosquito-killing coil that has a persistent insecticidal effect even after burning, and is characterized in that it contains: At least one insecticidal ingredient selected from the group consisting of Metrin, Profluthrin and Byfulin, and a carbide substrate with an iodine adsorption energy of 200 mg/g or less.

According to the composition of the persistent mosquito-killing incense stick, in addition to containing at least one insecticidal component selected from the group consisting of metrin, profluthrin, and bifulin, and containing a carbide substrate with an iodine adsorption capacity of 200 mg/g or less, even after burning, the insecticidal component remains in the air after a long period of time, so the insecticidal effect can be sustained for a long time. In addition, the carbide substrate with an iodine adsorption capacity of 200 mg/g or less can reduce the odor or irritation caused by smoke and the like during combustion while preventing excessive decomposition of insecticidal components and reducing the insecticidal effect.

In the persistent mosquito-killing line incense related to the present invention, preferably The amount of volatilization per unit time of the aforementioned insecticidal component during combustion is set at 0.05-15 mg/min.

According to the persistent mosquito-killing incense stick of this configuration, since the volatilization amount of the insecticidal component per unit time is within the above-mentioned range, a sufficient amount of the insecticidal component can be volatilized in the air even if it is burned for a short time.

In the persistent mosquito-killing line incense related to the present invention, preferably Set the burn time within 30 minutes.

According to the continuous mosquito-killing incense stick of this configuration, by setting the burning time within 30 minutes and burning the incense stick just before going to bed, mosquitoes can be prevented and it becomes an easy-to-use product.

In the persistent mosquito-killing line incense related to the present invention, preferably The duration of the insecticidal effect after burning is set at more than 8 hours.

According to the persistent mosquito-killing incense stick of this composition, by setting the duration of the insecticidal effect after burning at more than 8 hours, when used at night, human beings will not be bitten by mosquitoes all night, and can sleep comfortably. Also, if the burning time is set within 30 minutes, if the duration of the insecticidal effect after each burning is set at 8 hours, when people want to fall asleep, the fire of the continuous mosquito killing coil incense will be extinguished, so there is no need to worry about fire, and it can be used safely even at night.

In the persistent mosquito-killing incense stick of the present invention, it is preferable to set the blending amount of the aforementioned insecticidal components as C _I (mg), and when the volatilization of the aforementioned insecticidal components during complete combustion is defined as V (mg), it is set in a manner that satisfies the following formula (1), .

According to the persistent mosquito-killing coil of this configuration, by satisfying the above-mentioned formula (1), it is possible to disperse a sufficient amount of the insecticidal ingredient in the air while suppressing the blending amount of the insecticidal ingredient.

In the persistent mosquito-killing line incense of the present invention, it is preferable to set the blending amount of the aforementioned insecticidal components as C _I (mg), the blending amount of the aforementioned carbide substrate as C _B (g), and when the iodine adsorption energy of the aforementioned carbide substrate is defined as A (mg/g), the following formula (2) is satisfied: .

According to the persistent mosquito-killing incense stick of this configuration, by satisfying the above-mentioned formula (2), while preventing excessive decomposition of the insecticidal component by the iodine adsorption energy of the carbide substrate, an appropriate amount of the insecticidal component can be volatilized after burning for a long time after the insecticidal effect.

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

〔Persistent Mosquito Killing Incense〕 The persistent mosquito-killing incense stick of the present invention contains insecticidal ingredients and carbide substrates. For example, it is obtained by adding an appropriate amount of water to the mixed powder containing insecticidal ingredients and carbide substrates, kneading them, molding them with extruders and punching machines, and then drying them naturally or by heating. In the mixed powder, as other substrates, it can be blended with combustion enhancers, extenders and binders. However, the insecticidal ingredient is not directly mixed into the mixed powder, and it is okay to spray or apply a liquid agent containing the insecticidal ingredient after molding. The size of the continuous mosquito killing coil is preferably set at a total length of 100mm or less, a thickness of 7mm or less, and a weight of 5g or less, more preferably a total length of 20mm to 90mm, a thickness of 2mm to 5mm, and a weight of 0.2g to 3g. As the shape of the persistent mosquito-killing incense stick, rod shape, swirl shape, cone shape, plate shape, etc. can be appropriately selected according to the purpose of use, but rod shape, swirl shape, and plate shape are preferred.

As the insecticidal ingredient, methenin, profluthrin, or befullin, which are pyrethrin-based insecticidal ingredients that are volatile at room temperature, are used. In the chemical structure of these pyrethrin-based insecticidal ingredients, if there are optical isomers or geometric isomers based on asymmetrical carbon or double bonds, any isomers can be used. These pyrethrin-based insecticidal ingredients can be used alone or as a mixture of two or more, but preferably include methenin. Here, the term "volatile at room temperature" means that the vapor pressure at 30°C is 2×10 ^-4 to 1×10 ^-2 mmHg. Due to their volatile properties at room temperature, Metrin, Profluthrin and Byfulin can remain in the air after burning for a long time in the continuous mosquito-killing coil, so they can maintain the insecticidal effect for a long time. In addition, methenin, profluthrin, and Byfulin can exert a sustained insecticidal effect by adhering to walls and the like after being evaporated, and by contacting mosquitoes that have the habit of stopping on walls and the like. Also, in this specification, the insecticidal effect includes the pest repelling effect in which pests do not approach, in addition to the effect of killing or knocking down pests.

The content of the insecticidal component is preferably from 0.1 to 5% by weight, more preferably from 0.2 to 3% by weight, based on the weight of the entire persistent mosquito-killing incense stick. When the content of the insecticidal component is less than 0.1% by weight, sufficient insecticidal effect may not be obtained. When the content of the insecticidal component exceeds 5% by weight, since the insecticidal component is not a component that contributes to direct combustion, there is a possibility of persistent extinguishment of the mosquito-killing coil.

As the carbide substrate, a carbide substrate having an iodine adsorption energy of 200 mg/g or less is used. As the carbide base material, specifically, charcoal, bamboo charcoal, plant-based activated carbon, coconut shell charcoal, and coffee dregs charcoal are derived from plant-derived carbide base materials, and carbon black, graphite, acetylene black, coal-based activated carbon, and petroleum-based activated carbon are derived from non-plant-based carbide base materials, especially carbide base materials derived from plant-based materials are preferred. Although the details will be described in the following examples, when the persistent mosquito-killing coil is blended with a carbide substrate with an iodine adsorption energy of 200 mg/g or less, it can prevent excessive decomposition of insecticidal components due to the iodine adsorption energy of the carbide substrate, while effectively reducing or alleviating the odor or irritation caused by the smoke caused by the burning of the persistent mosquito-killing coil. When the iodine adsorption capacity of the carbide substrate exceeds 200 mg/g, the insecticidal component may be excessively decomposed, and a sufficient insecticidal effect may not be obtained. In addition, in the persistent mosquito-killing coil of the present invention, plural types of carbide substrates having different iodine adsorption energies may be mixed and used so that the iodine adsorption energy becomes 200 mg/g or less. Furthermore, the iodine adsorption energy was measured in accordance with the activated carbon test method stipulated in JIS K 1474.

The content of the carbide base material is preferably 20 to 80% by weight relative to the weight of the entire persistent mosquito-killing coil. When the content of the carbide base material is less than 20% by weight, there is a possibility that the odor or irritation caused by smoke or the like during combustion cannot be sufficiently alleviated. When the content of the carbide base material exceeds 80% by weight, there is a possibility that the formability and strength of the persistent mosquito-killing coil cannot be ensured.

Combustion enhancer is blended in order to stably burn the continuous mosquito killing line incense. The extender is blended in order to improve the formability of the persistent mosquito-killing coil. Adhesives are blended with raw materials as solidified adhesives. Combustion enhancers, bulking agents and binders become the base material of persistent mosquito-killing coils. Examples of suitable combustion enhancers include wood powder, pyrethrum extract meal powder, citrus peel powder, tea powder, coconut shell powder, and the like. These combustion aids can be used alone or as a mixture of two or more. Examples of suitable extenders include diatomaceous earth, talc, clay, kaolin and the like. These extenders can be used alone or as a mixture of two or more. Examples of suitable binders include milled flour, starch (α starch, tapioca flour, etc.), methylcellulose, carboxymethylcellulose (CMC), and the like. These binders can be used alone or as a mixture of two or more. The carbide base material, combustion aid, extender and binder are the base material of the persistent mosquito-killing coil, and the content of the base material is preferably more than 90% by weight relative to the weight of the continuous mosquito-killing coil.

Mosquito-killing incense sticks are usually given a scent suitable for incense sticks, but recently, for the purpose of obtaining an aroma effect or a relaxing effect, various fragrance ingredients with volatile properties are sometimes added. The persistent mosquito-killing coil of the present invention can suppress the odor or irritation caused by smoke and the like during combustion, and maintain the insecticidal effect for a long time regardless of the addition of fragrance components. Examples of fragrance ingredients include galaxolide, muskone, hexyl cinnamaldehyde, Iso E Super, methyl dihydrojasmonate, ethylene brassylate, geraniol, methyl atrarate, hexyl salicylate, tricyclodecenyl acetate, and β-naphthyl methyl ketone (or Anger crystal), ambroxan, Tonalide (6-acetyl-1,1,2,4,4,7-hexamethyltetrahydronaphthalene), γ-undecalactone, Cashmeran, Calone, heliotropin, indenyl-2,4-dioxane, α-isomethyl ionone, indole, Methyl cedryl ketone, methyl β-naphthyl ketone, rosephenone, coumarin, vanillin, styrax resinoid, benzyl benzoate, undecanal, benzyl salicylate, ionone, α-ionone, β-ionone, lily aldehyde, 3,5 -Dinitro-2,6-dimethyl-4-t-butylacetophenone, acetylcedrene, 2-cyclohexylene-2-phenylacetaldehyde, isolongifolanone, cis-3-hexenal, etc. These fragrance components can be used alone or as a mixture of two or more. The content of the fragrance component is preferably from 0.001 to 5% by weight, more preferably from 0.01 to 1% by weight, based on the weight of the entire persistent mosquito-killing coil. When the content of the fragrance component is less than 0.001% by weight, sufficient aroma may not be produced. When the content of the fragrance component exceeds 5% by weight, the odor may be excessively enhanced or stimulated.

The persistent mosquito-killing coil of the present invention may also contain antifungal agents, preservatives, stabilizers, efficacy enhancers, deodorants, etc. as other components. Examples of antifungal agents and preservatives include dehydroacetates, sorbates, p-hydroxybenzoates, and the like. Examples of stabilizers include 2,6-di-tert-butyl-4-methylphenol (BHT), 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), 4,4'-butylenebis(3-methyl-6-tert-butylphenol), 4,4'-thiobis(3-methyl-6-tert-butylphenol), 2-tert-butyl-6 -(3-tert-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, etc. By adding such a stabilizer, not only the stability of the insecticidal ingredient over time during storage, but also the stability during smoking can be significantly enhanced, which in turn helps to improve the effectiveness of the active ingredients after volatilization. The amount of the stabilizer added is preferably 0.01 to 0.5 times the amount of the insecticidal component. Examples of potency enhancers include piperonyl butoxide, N-(2-ethylhexyl)-bicyclo[2,2,1]hept-5-ene-2,3-dicarboxyimide, and the like. In addition, the persistent mosquito killing line incense may also contain coloring agents such as malachite green and food additives (food blue No. 1, food yellow No. 4, food red No. 106, etc.).

[burning time] Although the previous mosquito-killing incense sticks used the burning smoke to disperse the insecticidal ingredients to prevent mosquitoes, etc., but the use at bedtime can also avoid the generation of smoke. In the persistent mosquito-killing coil of the present invention, even after burning for a long time, the insecticidal component remains in the air, and the insecticidal effect can be sustained. Therefore, the usability can be improved by setting the burning time in an appropriate range. The burning time of the persistent mosquito killing line incense of the present invention from ignition to burnout is preferably within 30 minutes. By setting the burning time within 30 minutes, it can prevent mosquitoes after a long time during bedtime, but in the short time before going to bed or just after going to bed, the continuous burning of the mosquito-killing coil coil can be completed, so you can go to bed without worrying about smoke. Still, after the burning of the persistent mosquito-killing thread incense, the duration of the insecticidal effect (the time during which mosquitoes can be controlled) is preferably more than 8 hours, more preferably more than 10 hours, and most preferably more than 12 hours. By setting the duration of the insecticidal effect after burning to more than 8 hours, for example, when used at night, human beings will not be bitten by mosquitoes throughout the night and can sleep comfortably. Also, if each burning time is set within 30 minutes, the duration of the insecticidal effect after burning is set at 8 hours. When people want to fall asleep, the fire of the continuous mosquito-killing coil incense will be extinguished, so there is no need to worry about fire, and it can be used safely even at night. In this way, although the burning time of the persistent mosquito-killing incense stick of the present invention is short, it still has the insecticidal effect for a long time, so it is suitable for indoor use, especially for use in highly airtight spaces. However, the persistent mosquito-killing coil of the present invention can of course also be used outdoors.

〔Volatilization of insecticidal ingredients per unit time〕 The persistent mosquito-killing incense stick of the present invention sets the volatilization amount of the insecticidal component per unit time during combustion in an appropriate range, so that a sufficient amount of the insecticidal component can be volatilized in the air even for short-term combustion. Here, the volatile amount of the insecticidal components of the persistent mosquito-killing coil is completely burned, which is calculated by connecting the exhaust bell with a glass tube equipped with silica gel to completely burn the persistent mosquito-killing coil, and sucking the air in the exhaust bell with a pump to trap the insecticidal components volatilized by combustion, and calculate the trapped insecticidal components by gas chromatography. The amount of volatilization per unit time divided by the volatilization amount of the insecticidal component thus calculated is preferably 0.05 to 15 mg/min, more preferably 0.1 to 10 mg/min. If the volatilization amount of the insecticidal component per unit time is within the above-mentioned range, an appropriate amount of the insecticidal component can be volatilized in the air even for a short-time combustion of less than 30 minutes. In addition, if the volatilization amount of the insecticidal component per unit time is within the above range, even if the iodine adsorption energy of the carbide substrate is 200 mg/g or less, the odor or irritation caused by smoke or the like during combustion can be reduced. When the volatilization amount of the insecticidal ingredient per unit time is less than 0.05 mg/min, the short-term combustion of less than 30 minutes may not be able to disperse a sufficient amount of the insecticidal ingredient in the air, and the insecticidal effect may not be sustained. When the volatilization amount per unit time of the insecticidal component exceeds 15 mg/min, there may be a possibility that the odor or irritation caused by smoke or the like during combustion cannot be sufficiently alleviated. Furthermore, since the insecticidal component is not a component that contributes to direct combustion, there is a possibility of persistent extinguishment of the mosquito-killing coil.

[Insecticidal Component Maintenance Rate] In the persistent mosquito-killing incense stick of the present invention, when the compounding amount of the insecticidal component is defined as C _I (mg), and the volatilization amount of the insecticidal component at the time of complete combustion is defined as V (mg), the ratio of the volatile amount V of the insecticidal component to the compounded amount C _I of the insecticidal component is the maintenance rate of the insecticidal component, and preferably satisfies the following formula (1). Insecticidal ingredient maintenance rate=(V/C _I )×100≧40 ･･･(1) By satisfying the condition of formula (1), since the insecticidal ingredient is excessively decomposed during the storage and combustion of the persistent mosquito-killing coil, it is possible to suppress the blending amount of the insecticidal ingredient during manufacture, and at the same time disperse a sufficient amount of the insecticidal ingredient in the air during combustion. When the maintenance rate of the insecticidal ingredient is less than 40%, the amount of the insecticidal ingredient necessary for the manufacture of the persistent mosquito-killing coil increases, which may become economically disadvantageous. Also, since the insecticidal component is not a component that contributes to direct combustion, increasing the blending amount of the insecticidal component may result in the possibility of continuous extinguishment of the mosquito-killing coil.

[Insecticidal Component/Absorptive Energy Ratio] In mosquito-killing coils, the blending amount of the insecticidal component is defined as C _I (mg), the blending amount of the carbide base material is defined as C _B (g), and the iodine adsorption energy of the carbide base material is defined as A (mg/g), the product of the blending amount C _B of the carbide base material and the iodine adsorption energy A of the carbide base material represents the total amount of iodine adsorption of the entire persistent mosquito-killing coil. Here, the ratio of the blending amount C I _of the insecticidal component to the product of the blending amount C _B of the carbide base material and the iodine adsorption energy A of the carbide base material, that is, the ratio of the insecticidal component/adsorption energy ratio, affects the volatilization amount of the insecticidal component. In the persistent mosquito-killing coil of the present invention, the insecticidal component/adsorption energy ratio preferably satisfies the following formula (2). Insecticidal ingredient/adsorption energy ratio=C _I /(C _B ×A)≧3×10 ^-2 ･･･(2) By satisfying the formula (2), relative to the blending amount of the insecticidal ingredient at the time of manufacture, the ratio of the insecticidal ingredient that can be decomposed by the iodine adsorption of the carbide substrate becomes very small during storage and combustion of the persistent mosquito-killing coil. Therefore, even if a part of the insecticidal component is decomposed during storage and burning of the persistent mosquito-killing coil incense, an appropriate amount of the insecticidal component that can last for a long time can be released after burning. When the insecticidal ingredient/adsorption energy ratio is less than 3×10 ^-2 , the ratio of the insecticidal ingredient that can be decomposed by the iodine adsorption of the carbide substrate increases during storage and combustion of the persistent mosquito-killing coil relative to the blending amount of the insecticidal ingredient during manufacture, and there is a risk that the insecticidal ingredient volatilized during combustion is insufficient.

〔Target pests〕 The persistent mosquito-killing incense of the present invention is not particularly limited as the object of pest control, but examples include house mosquitoes such as house mosquitoes, house mosquitoes, tropical house mosquitoes, underground house mosquitoes, Aedes mosquitoes such as A. Crawling pests such as cockroaches, mites, ants, temperate bedbugs, rodents, carcasses, corn weevils, etc. Among these pests, it is especially effective against house mosquitoes and Aedes mosquitoes. [Example]

[Example 1] Mix charcoal powder A (50 parts by weight) with an iodine adsorption capacity of 25 mg/g as a carbide base material, metrin (1.5 parts by weight) as an insecticidal component, a mixed fragrance (0.8 parts by weight) including musk musk and musk ketone as a fragrance component, plant powder as a combustion enhancer and extender, that is, pyrethrum extract powder (17 parts by weight), wood powder (10.7 parts by weight) and diatomaceous earth (3 parts by weight), and α Starch (14 parts by weight), and carboxymethylcellulose (CMC) (3 parts by weight), to which water (90 parts by weight) was added and kneaded well. Put the kneaded product in an extruder to shape it into a stick shape, and then dry it until the moisture content becomes about 7-10% by weight, so as to make the persistent mosquito-killing coil of Example 1. The persistent mosquito-killing incense stick of Example 1 has an insecticidal component/adsorption energy ratio of 1.2 and satisfies the conditions of the aforementioned formula (2).

When the persistent mosquito-killing incense stick of Example 1 was used in a room of 10 tatami mats (area 16.7m ² , height 2.5m, volume 41.7m ³ ), although it burned out in about 23 minutes, after 12 hours of burning, mosquitoes and other pests did not approach. From this, it can be seen that after 12 hours after the burning of the persistent mosquito-killing coil of Example 1, the insecticidal ingredients are still sufficiently left in the room. In addition, the persistent mosquito-killing incense stick of Example 1 produces less smoke during combustion, does not feel irritating odor, and produces a light floral smell. The scent is relaxing and suitable for bedroom use.

[Examples 2-12] Using charcoal powder A with an iodine adsorption capacity of 25 mg/g as a carbide substrate, and charcoal powder B with an iodine adsorption capacity of 838 mg/g, blended in Table 1, and according to Example 1, a persistent mosquito-killing coil with the characteristics of the present invention was produced (Examples 2-12). The insecticidal component/adsorption energy ratios of the persistent mosquito-killing incense sticks of Examples 2-12 are 3.1×10 ^-2 -2.2, all of which satisfy the condition of the aforementioned formula (2).

[Comparative Examples 1-3] Using charcoal powder A with an iodine adsorption capacity of 25 mg/g as a carbide base material, and/or charcoal powder B with an iodine adsorption capacity of 838 mg/g, blended in Table 2, according to Example 1, a persistent mosquito-killing coil that does not have the characteristic constitution of the present invention was produced (Comparative Examples 1-3). Compared with the provisions of the present invention, the persistent mosquito-killing incense sticks of Comparative Examples 1 to 3 are examples in which the iodine adsorption energy of the carbide substrate is larger, and the insecticidal component/adsorption energy ratio is 7.2×10 ^-3 to 2.2×10 ^-2 , which do not satisfy the conditions of the aforementioned formula (2).

〔Reference example〕 The carbide base material with iodine adsorption capacity was not used, and the blending shown in Table 2 was carried out according to Example 1 to make a persistent mosquito-killing coil (reference example).

Each test shown in the following (1)-(4) was performed using the persistent mosquito killing coils of Examples 1-12, Comparative Examples 1-3, and the reference example.

(1) Stability over time The insecticidal components contained in the persistent mosquito-killing coils stored at 50°C for one month were analyzed by gas chromatography, and the content of the insecticidal components after storage for one month and the blending amount of the insecticidal components at the time of manufacture were used to calculate the recovery rate of the insecticidal components. The stability over time was judged according to the following criteria. A: The recovery rate of insecticidal ingredients is over 95% B: The recovery rate of insecticidal components is more than 90% and less than 95%. C: The recovery rate of insecticidal components is less than 90%

(2) Maintenance rate of insecticidal ingredients The continuous combustion of the persistent mosquito-killing coil is done by connecting the exhaust bell with a glass tube equipped with silica gel, and the air in the exhaust bell is sucked by a pump to trap the insecticidal components volatilized by combustion, and the trapped insecticidal components are analyzed by gas chromatography to calculate the volatile amount of the persistent mosquito-killing coil when it is completely burned. Then, from the calculated amount of volatilization and the compounding amount of the insecticidal ingredient at the time of production, the insecticidal ingredient maintenance rate was calculated according to the above-mentioned formula (1).

(3) hobby In a glass cylinder with a diameter of 20cm and a height of 40cm, the continuous mosquito-killing coil was burned. 10 testers evaluated the stimulation mitigation and odor preference, with the highest point as 10 and the lowest point as 1. As the test result of the preference by the sensory test, the average value of the evaluations by 10 testers was calculated.

(4) On-site insecticidal efficacy test In the center of a closed room of 25m ³ , burn continuous mosquito-killing incense sticks. After 8 hours of burning, put 50 adult females of the house mosquito and expose them for 2 hours, and recover all the mosquitoes for testing. Meanwhile, with the passage of time, count the female adults of S. aurantias that were falling and turning upwards, and set the time point when 25 female adults of S. acerophyllums were falling and turning upwards as the KT ₅₀ value (rounded up below the decimal point).

The persistent mosquito-killing coils of Examples 1 to 12, which contain Metrin, Profluthrin, or Bifulin as insecticidal ingredients, and carbide substrates with an iodine adsorption energy of 200 mg/g or less, have excellent stability over time. The insecticidal ingredient maintenance rate of any of them is more than 40%. Even if burned for a short period of time within 30 minutes, the KT ₅₀ value after 12 hours of self-burning is below 30 minutes, and the excellent insecticidal effect is sustained. It is considered that the persistent mosquito-killing coils of Examples 1 to 12 have the same level of stability over time as the reference example that does not incorporate a carbide substrate with iodine adsorption energy, and the insecticidal effect after 12 hours of self-combustion. Therefore, by suppressing the iodine adsorption energy of the carbide substrate to be below 200 mg/g, the decomposition of excess insecticidal components by the carbide substrate will not occur.

In addition, compared with the persistent mosquito-killing coils of the reference example, compared to the concerns about the smell of smoke or the large amount of smoke, the persistent mosquito-killing coils of Examples 1 to 12 all emit a high-favorite fragrance after burning, and do not overfill the smoke. They are easy to use in actual use because they are excellent in irritation relief and odor preference. From this, it can be seen that the persistent mosquito-killing coils of Examples 1 to 12 are considered to be sufficiently effective in reducing odor or irritation caused by smoke or the like during combustion even if the iodine adsorption energy of the carbide substrate is 200 mg/g or less.

Furthermore, among the persistent mosquito-killing coils of Examples 1-12, it was observed that the insecticidal components had a lower volatilization amount per unit time (Examples 4-6, 8), and the effectiveness tended to decrease slightly. Also, in Example 3, where the volatilization amount per unit time was 10.2 mg/min, which was extremely large, there were cases where the burning of the persistent mosquito-killing coil could not last to the end. Therefore, the volatilization amount of the insecticidal component per unit time is preferably 0.05-15 mg/min, more preferably 0.1-10 mg/min.

When comparing Example 9 with Example 1, although the blending amounts of insecticidal components and carbide substrates are the same, and only the types of fragrance components are different, the maintenance rate of insecticidal components and the KT ₅₀ value after 12 hours of self-combustion are not much different. When comparing Example 10 with Example 1, although the blending amount of the insecticidal component and the carbide substrate is the same, and the point of not blending the fragrance component is different, the maintenance rate of the insecticidal component and the _KT50 value after 12 hours of self-combustion are not much different. From this, it can be seen that the type or blending amount of the fragrance ingredient does not have a significant impact on the decomposition of the insecticidal ingredient by the iodine adsorption energy of the carbide substrate.

On the other hand, like Comparative Examples 1-3, as the insecticidal ingredient, although methenin is contained, but when the carbide base material with the iodine adsorption capacity exceeding 200 mg/g is contained, the stability of the insecticidal ingredient over time is not sufficient, the maintenance rate of the insecticidal ingredient is lower than 40%, and the _KT50 value after 12 hours of self-combustion is also more than 120 minutes, and a sufficient insecticidal effect cannot be obtained. This is considered to be because the iodine adsorption energy by the carbide substrate exceeds 200 mg/g, resulting in decomposition of excess insecticidal components by the carbide substrate. In addition, in the persistent mosquito-killing coils of Comparative Examples 1 to 3, it was difficult to feel the fragrance by the fragrance components, and it was a result of feeling that the fragrance tone had deteriorated. [Industrial availability]

The persistent mosquito-killing coil of the present invention can be used as a household or business-use mosquito-killing coil, and can be used to control pests, especially for mosquitoes such as sharp-spotted house mosquitoes, underground house mosquitoes, and Aedes albopictus.

Claims (5)

A persistent mosquito-killing incense stick, which is a persistent mosquito-killing incense stick that has a persistent insecticidal effect even after burning, is characterized in that it contains: at least one insecticidal component selected from the group consisting of Metofluthrin, Profluthrin, and Transfluthrin, and a carbide substrate derived from plants. For example, the persistent mosquito-killing coil incense of claim 1, the burning time is set within 30 minutes. For example, the persistent mosquito-killing thread incense according to claim 1 or 2, which sets the duration of the insecticidal effect after burning to more than 8 hours. Such as claim 1 or 2 of the persistent mosquito-killing line incense, wherein, when the blending amount of the aforementioned insecticidal component is defined as C _I (mg), and the volatilization amount of the aforementioned insecticidal component at the time of complete combustion is defined as V (mg), it is set in a manner that satisfies the following formula (1), (V/C _I )×100≧40‧‧‧(1). For the persistent mosquito-killing incense stick according to claim 1 or 2, wherein, when the blending amount of the aforementioned insecticidal component is set as C _I (mg), the blending amount of the aforementioned carbide base material is set as C _B (g), and the iodine adsorption energy of the aforementioned carbide base material is set as A (mg/g), the following formula (2) is satisfied: C _I /(C _B ×A)≧3×10 ⁻² ‧‧‧(2).