JP7213379B2 - Long-lasting mosquito coil - Google Patents

Description

The present invention relates to a long-lasting mosquito coil whose insecticidal effect persists even after burning.

Mosquito coils are widely used as products for exterminating flying pests such as mosquitoes, in which insecticidal components are volatilized in a space to be treated by smoking. The burning time of one mosquito coil is set to about 7 to 8 hours according to the sleeping time of a person, and until it burns out, it knocks down or kills the pests existing in the space to be treated, and furthermore, the pests from the space. act to eliminate or avoid

By the way, in recent years, due to the improvement of sanitary environment and changes in housing conditions, especially apartments in urban areas are becoming more airtight. decreasing. Therefore, if mosquitoes and the like in the room are exterminated before going to bed, it is no longer necessary to volatilize the insecticidal component continuously during bedtime unlike the conventional mosquito-repellent incense. Under these circumstances, attempts have been made to shorten the burning time of mosquito-repellent incense sticks, which have been considered to be used continuously for a long period of time.

For example, there is a mosquito-repellent incense using room-temperature volatile pyrethroids such as metofruthrin, profluthrin, and transfluthrin as an insecticidal component (see, for example, Patent Document 1). In the mosquito-repellent incense of Patent Document 1, the insecticidal component remains in the air for a long time after burning, so the insecticidal effect lasts for a long time even if the burning time is shortened.

JP 2011-12056 A

Mosquito-repellent incense, on the other hand, is required to have insecticidal components, fragrance components, and further, products with reduced odors and stimuli caused by smoke and the like. However, Patent Document 1 focuses on volatilizing the necessary amount of insecticidal component while shortening the combustion time, and there is room for further study on reducing irritation during combustion.

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

The characteristic configuration of the long-lasting mosquito coil according to the present invention for solving the above problems is
A long-lasting mosquito coil whose insecticidal effect persists even after burning,
at least one insecticidal component selected from the group consisting of metofruthrin, profluthrin, and transfluthrin;
a carbide substrate having an iodine adsorption capacity of 200 mg/g or less;
is to contain

According to the long-lasting mosquito coil of this configuration, in addition to at least one insecticidal component selected from the group consisting of metofruthrin, profluthrin, and transfluthrin, it contains a carbide base material having an iodine adsorption capacity of 200 mg/g or less. By doing so, the insecticidal component remains in the air for a long time even after combustion, and the insecticidal effect can be maintained for a long time. In addition, the charcoal base material having an iodine adsorption capacity of 200 mg/g or less can reduce odors and irritation caused by smoke, etc. during combustion while preventing excessive decomposition of the insecticidal component and reducing the insecticidal effect. can.

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

According to the long-lasting mosquito repellent incense of this configuration, since the amount of volatilization of the insecticidal component per unit time is within the above range, a sufficient amount of the insecticidal component can be volatilized into the air even if it is burned for a short time. be able to.

In the long-lasting mosquito coil according to the present invention,
It is preferable that the combustion time is set within 30 minutes.

According to the long-lasting mosquito-repellent incense of this configuration, since the burning time is set within 30 minutes, mosquitoes can be controlled only by burning before going to bed, and it is a user-friendly product.

In the long-lasting 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 longer.

According to the long-lasting mosquito coil of this configuration, the duration of the insecticidal effect after burning is set to 8 hours or more, so that when used at night, people are not bitten by mosquitoes all night long. , can sleep comfortably. In addition, if the burning time is set to 30 minutes or less and the duration of the insecticidal effect after burning is set to 8 hours, the flame of the long-lasting mosquito coil will go out when the person falls asleep, so there is no need to worry about fires. It can be safely used even at night.

In the long-lasting mosquito coil according to the present invention,
When the compounding amount of the insecticidal component is C _I (mg) and the volatilization amount of the insecticidal component upon complete combustion is V (mg), the following formula (1):
(V/C _I )×100≧40 (1)
is preferably set so as to satisfy

According to the long-lasting mosquito coil of this configuration, by satisfying the above formula (1), a sufficient amount of the insecticidal component can be volatilized into the air while suppressing the blending amount of the insecticidal component.

In the long-lasting mosquito coil according to the present invention,
When the compounding amount of the insecticidal component is C _I (mg), the compounding amount of the carbide base material is C _B (g), and the iodine adsorption capacity of the carbide base material is A (mg/g), the following Formula (2):
C _I / (C _B ×A) ≥ 3 × 10 ^-2 (2)
is preferably satisfied.

According to the long-lasting mosquito coil of this configuration, by satisfying the above formula (2), the insecticidal component is prevented from being excessively decomposed due to the iodine adsorption capacity of the carbide base material, and the insecticidal effect is prolonged after burning. A suitable amount of insecticidal component can be volatilized which can last for a period of time.

The long-lasting mosquito coil of the present invention is described below. However, the present invention is not intended to be limited to the configurations described in the embodiments described below.

[Long-lasting mosquito coil]
The long-lasting mosquito coil of the present invention contains an insecticidal component and a charcoal base material. is obtained by molding with an extruder, a punching machine, etc., and then air-drying or heat-drying. The mixed powder can be blended with other base materials such as a flame retardant, a bulking agent, and a binder. The insecticidal component may not be directly blended into the mixed powder, but may be sprayed or coated with a liquid containing the insecticidal component after molding. The size of the long-lasting 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. is more preferable. The shape of the long-lasting mosquito-repellent incense can be appropriately selected according to the purpose of use, such as rod-like, spiral-like, cone-like, and plate-like, but preferably rod-like, spiral-like, and plate-like.

Metofluthrin, profluthrin, or transfluthrin, which is a pyrethroid insecticidal component having room temperature volatility, is used as the insecticidal component. If the chemical structure of these pyrethroid insecticidal components contains optical isomers or geometric isomers based on an asymmetric carbon or double bond, any isomers can be used. These pyrethroid-based insecticidal components can be used singly or as a mixture of two or more, but preferably contain metofruthrin. Here, having room temperature volatility means having a vapor pressure of 2×10 ⁻⁴ to 1×10 ⁻² mmHg at 30°C. Metofluthrin, profluthrin, and transfluthrin are volatile at room temperature, so they remain in the air for a long time even after burning the long-lasting mosquito coil, so it is possible to maintain the insecticidal effect for a long time. be. In addition, metofluthrin, profluthrin, and transfluthrin partially adhere to walls after volatilization, and exert a sustained insecticidal effect even when mosquitoes, which have the habit of stopping on walls, come into contact with them. be able to. In this specification, the insecticidal effect includes not only the effect of killing or knocking down pests but also the pest repelling effect of keeping pests away.

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 long-lasting 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 long-lasting mosquito coil may fade out because the insecticidal component does not directly contribute to combustion.

As the carbide substrate, a carbide substrate having an iodine adsorption capacity of 200 mg/g or less is used. Specific examples of the carbide base material include charcoal, bamboo charcoal, vegetable activated carbon, coconut shell charcoal, and coffee grounds charcoal. Non-vegetable carbonized substrates such as activated carbon and petroleum activated carbon can be used, and vegetable-derived carbonized substrates are particularly preferred. Details will be described in the examples below, but when a carbonized base material having an iodine adsorption capacity of 200 mg / g or less is blended into a long-lasting mosquito coil, excessive decomposition of the insecticidal component due to the iodine adsorption capacity of the carbonized base material occurs. While preventing this, it is possible to effectively reduce or alleviate odors and irritation caused by smoke or the like during burning of long-lasting mosquito coils. If the iodine adsorption capacity of the carbide base material exceeds 200 mg/g, the insecticidal component may be excessively decomposed, failing to obtain a sufficient insecticidal effect. Moreover, in the long-lasting mosquito coil of the present invention, it is possible to use a mixture of a plurality of types of carbonized base materials having different iodine adsorption capacities so that the iodine adsorption capacity 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 charcoal base material is preferably 20 to 80% by weight based on the total weight of the long-lasting mosquito coil. If 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 or the like during combustion cannot be sufficiently alleviated. If the content of the carbide base material exceeds 80% by weight, there is a possibility that the formability and strength of the long-lasting mosquito coil cannot be ensured.

The flame retardant is blended to stably burn the long-lasting mosquito coil. The bulking agent is blended to enhance the formability of the long-lasting mosquito coil. The binding agent is blended as a binder that binds and hardens the raw materials. The flame retardant, bulking agent, and binder are the base materials of long-lasting mosquito coils. Examples of suitable combustion-supporting agents include wood powder, pyrethrum extract lees powder, citrus peel powder, tea powder, coconut shell powder, and the like. These combustion-supporting agents can be used singly or as a mixture of two or more. Examples of suitable fillers include diatomaceous earth, talc, clay, kaolin, and the like. These extenders can be used singly or as a mixture of two or more. Examples of suitable binders include tab powder, starch (α starch, tapioca powder, etc.), methyl cellulose, carboxymethyl cellulose (CMC), and the like. These caking agents can be used singly or as a mixture of two or more. The charcoal base material, the flame retardant, the bulking agent, and the binder are the base materials of the long-lasting mosquito coil, and the content of the base material is 90% by weight or more of the total weight of the long-lasting mosquito coil. Preferably.

Mosquito-repellent incense is usually scented with an appropriate scent, but recently, various fragrant ingredients with volatility are sometimes added for the purpose of obtaining aroma effects and relaxing effects. The long-lasting mosquito repellent incense of the present invention can suppress the odor and irritation caused by smoke and the like during combustion, regardless of the presence or absence of the addition of fragrance ingredients, and can maintain the insecticidal effect for a long time. Also in the long-lasting mosquito-repellent incense of the invention, various perfume components can be added for the purpose of obtaining aroma effects and relaxing effects. Examples of perfume ingredients include galaxolide, musk ketone, hexyl cinnamic aldehyde, isoe super, methyl dihydrojasmonate, ethylene brassylate, geraniol, methyl atralate, hexyl salicylate, tricyclodecenyl acetate, oranger crystal, ambro xane, tonalide (6-acetyl-1,1,2,4,4,7-hexamethyltetralin), γ-undecalactone, cashmeran, charon, heliotropine, dihydroindenyl-2,4-dioxane, α - isomethylionone, indole, methyl cedryl ketone, methyl β-naphthyl ketone, rosephenone, coumarin, vanillin, styrax resinoid, benzyl benzoate, undecanal, benzyl salicylate, ionone, α-ionone, β-ionone , lylyaldehyde, 3,5-dinitro-2,6-dimethyl-4-t-butylacetophenone, acetylcedrene, 2-cyclohexylidene-2-phenylacetaldehyde, isolongiphoranone, and cis-3-hexenol, etc. is mentioned. These perfume ingredients can be used singly 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 long-lasting mosquito coil. If the content of the perfume component is less than 0.001% by weight, it may not be possible to produce a sufficient fragrance. If the content of the perfume component exceeds 5% by weight, the odor and irritation may become too strong.

The long-lasting mosquito-repellent incense of the present invention may contain other components such as antifungal agents, preservatives, stabilizers, potency enhancers and deodorants. Examples of antifungal agents or preservatives include dehydroacetate, sorbate, p-hydroxybenzoate, 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-tertiarybutylphenol), 4,4'-butylidenebis (3-methyl-6-tertiarybutylphenol), 4,4'-thiobis (3-methyl-6-tertiarybutylphenol), 2-tertiary Butyl-6-(3-tert-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxy benzoate and the like. By adding such a stabilizer, not only the stability of the insecticidal component over time during storage, but also the stability during smoking is remarkably enhanced, and the efficacy of the active ingredient after volatilization is improved. can also contribute. The amount of the stabilizer to be added is preferably 0.01 to 0.5 times the amount of the insecticidal component. Exemplary potency enhancers include piperonyl butoxide, N-(2-ethylhexyl)-bicyclo[2,2,1]hept-5-ene-2,3-dicarboximide, and the like. Further, the long-lasting mosquito coil can 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]
Conventional mosquito-repellent incense repels mosquitoes and the like by volatilizing insecticidal components through smoking during combustion, but the generation of smoke may be avoided when used at bedtime. In the long-lasting mosquito coil of the present invention, the insecticidal component remains in the air for a long time even after burning, and the insecticidal effect can be sustained. can be improved. The long-lasting mosquito coil of the present invention preferably has a burning time of 30 minutes or less from ignition to burnout. By setting the burning time to within 30 minutes, it is possible to control mosquitoes for a long time while sleeping, and at the same time, the long-lasting mosquito coil burns in a short period of time before going to bed or immediately after going to bed. After finishing, you can go to bed without worrying about smoke or the like. After burning the long-lasting mosquito coil, the duration of the insecticidal effect (time during which mosquitoes can be controlled) is preferably 8 hours or longer, more preferably 10 hours or longer, and most preferably 12 hours or longer. 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. In addition, if the burning time is set to 30 minutes or less and the duration of the insecticidal effect after burning is set to 8 hours, the flame of the long-lasting mosquito coil will go out when the person falls asleep, so there is no need to worry about fires. It can be safely used even at night. In this way, the long-lasting mosquito coil of the present invention has a short burning time, but the insecticidal effect lasts for a long time, so it is suitable for indoor use, especially in a highly airtight space. suitable for use in However, the long-lasting mosquito coil of the present invention can of course be used outdoors.

[Volatilization amount per unit time of insecticidal component]
In the long-lasting mosquito coil of the present invention, by setting the volatilization amount of the insecticidal component per unit time during combustion to an appropriate range, a sufficient amount of the insecticidal component can be released into the air even if it is burned for a short time. can volatilize. Here, the volatilization amount of the insecticidal component when the long-lasting mosquito coil is completely burned is calculated by completely burning the long-lasting mosquito coil in an exhaust bell connected to a glass tube filled with silica gel. Air is drawn in with a pump to trap the insecticidal components volatilized by combustion, and the trapped insecticidal components are analyzed by gas chromatography. The volatilization amount per unit time obtained by dividing the volatilization amount of the insecticidal component calculated in this way by the combustion time is preferably 0.05 to 15 mg/min, more preferably 0.1 to 10 mg/min. preferable. If the volatilization amount of the insecticidal component per unit time is within the above range, it is possible to volatilize an appropriate amount of the insecticidal component into the air even with short-time combustion of 30 minutes or less. In addition, if the volatilization amount of the insecticidal component per unit time is within the above range, the odor and irritation caused by smoke, etc. during combustion can be reduced even if the iodine adsorption capacity of the carbide substrate is 200 mg/g or less. be able to. When the volatilization amount of the insecticidal component per unit time is less than 0.05 mg/min, a sufficient amount of the insecticidal component cannot be volatilized into the air by short-time combustion of 30 minutes or less, and the insecticidal effect is sustained. There is a risk that it will not. If the volatilization amount of the insecticidal component per unit time exceeds 15 mg/min, there is a possibility that the odor and irritation caused by smoke and the like during combustion cannot be sufficiently alleviated. Furthermore, since the insecticidal component is not a component that directly contributes to combustion, there is a possibility that long-lasting mosquito coils will fade out.

[Insecticide retention rate]
In the long-lasting mosquito coil of the present invention, when the amount of the insecticidal component is C _I (mg) and the amount of the insecticidal component volatilized when completely burned is V (mg), the volatilized amount of the insecticidal component V The insecticidal component retention rate, which is the ratio of the compounding amount _CI of the insecticidal component to
Insecticidal component retention rate = (V/C _I ) x 100 ≥ 40 (1)
is preferably satisfied. By satisfying the condition of formula (1), the insecticidal component is not excessively decomposed during storage and burning of the long-lasting mosquito coil. A sufficient amount of the insecticidal component can be volatilized into the air. If the insecticidal component retention rate is less than 40%, the amount of the insecticidal component required for manufacturing the long-lasting mosquito coil increases, 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 long-lasting mosquito coil to fade out.

[insecticidal component/adsorption capacity ratio]
In the mosquito coil, when the compounding amount of the insecticidal component is _CI (mg), the compounding amount of the carbide base material is C _B (g), and the iodine adsorption capacity of the carbide base material is A (mg/g), The product of the blending amount CB of the charcoal base material and the iodine adsorption capacity _A of the charcoal base material indicates the total amount of iodine adsorbability of the entire long-lasting mosquito coil. Here, the insecticidal component/adsorption capacity ratio, which is the ratio of the compounded amount _CI of the insecticidal component to the product of the compounded amount C _B of the carbide substrate and the iodine adsorption capacity A of the carbide substrate, affects the volatilization amount of the insecticidal component. give. In the long-lasting mosquito coil of the present invention, the insecticidal component/adsorptive capacity ratio is expressed by the following formula (2):
Insecticidal component/adsorptive capacity ratio = C _I / (C _B × A) ≥ 3 × 10 ^-2 (2)
is preferably satisfied. By satisfying the formula (2), the proportion of the insecticidal component that is decomposed by the iodine adsorption capacity of the carbonized base material during storage and burning of the long-lasting mosquito coil against the amount of insecticidal component at the time of production is sufficient. to be small. Therefore, even if some insecticidal components are decomposed during storage and burning of the long-lasting mosquito coil, an appropriate amount of insecticidal components that can sustain the insecticidal effect for a long time after burning can be volatilized. . If the insecticidal component/adsorption capacity ratio is less than 3 × 10 ^-2 , the amount of the insecticidal component at the time of manufacture is decomposed by the iodine adsorption capacity of the charcoal base material during storage and combustion of the long-lasting mosquito coil. The ratio of the insecticidal component to be used becomes large, and there is a possibility that the insecticidal component that volatilizes during combustion may be insufficient.

[Pests to be controlled]
The pests to be controlled by the persistent mosquito coil of the present invention are not particularly limited. Flying pests such as flea flies, bees, gadflies, blackflies, midges, and mussels, as well as cockroaches such as German cockroaches, American cockroaches, and black cockroaches, ticks, ants, bedbugs, bookworms, bedbugs, maize weevil, etc. Among these pests, it is particularly effective against Culex and Aedes.

[Example 1]
Charcoal powder A (50 parts by weight) having an iodine adsorption capacity of 25 mg/g as a carbide base material, Metofluthrin (1.5 parts by weight) as an insecticidal component, and a mixed fragrance containing galaxolide, musk ketone, etc. as fragrance components ( 0.8 parts by weight), pyrethrum extract lees powder (17 parts by weight), wood flour (10.7 parts by weight), and diatomaceous earth (3 parts by weight), which are vegetable powders, as a combustion-supporting agent and bulking agent, and caking As agents, α-starch (14 parts by weight) and carboxymethyl cellulose (CMC) (3 parts by weight) were mixed, water (90 parts by weight) was added, and the mixture was sufficiently kneaded. The kneaded product was extruded into a rod shape and then dried until the water content reached about 7 to 10% by weight to produce a long-lasting mosquito coil of Example 1. The long-lasting mosquito coil of Example 1 had an insecticidal component/adsorptive capacity ratio of 1.2, satisfying the condition of the above formula (2).

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

[Examples 2 to 12]
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 as the charcoal base material. A long-lasting mosquito coil (Examples 2 to 12) having the characteristic configuration of was produced. The long-lasting mosquito coils of Examples 2 to 12 had an insecticidal component/adsorptive capacity ratio of 3.1 × 10 ^-2 to 2.2, and all satisfied the conditions of the above formula (2). .

[Comparative Examples 1 to 3]
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 as the charcoal base material, and the mixture shown in Table 2 was prepared according to Example 1. Persistent mosquito coils (Comparative Examples 1 to 3) not having the features of the present invention were produced. The long-lasting mosquito coils of Comparative Examples 1 to 3 are examples in which the iodine adsorption capacity of the charcoal base material is greater than the regulation of the present invention, and the insecticidal component/adsorption capacity ratio is also 7.2 × 10 ^-3 to 2. .2×10 ⁻² , and none of them satisfy the condition of the above formula (2).

[Reference example]
A long-lasting mosquito coil (reference example) was produced according to Example 1 according to the formulation shown in Table 2 without using the charcoal base material having iodine adsorption ability.

Using the long-lasting mosquito coils of Examples 1 to 12, Comparative Examples 1 to 3, and Reference Example, the following tests (1) to (4) were conducted.

(1) Stability over time The insecticidal components contained in the long-lasting mosquito coil after storage at 50 ° C for 1 month were 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 compounding 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 and 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 a long-lasting mosquito coil in an exhaust bell connected to a 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 volatilization amount of the insecticidal component when the long-lasting mosquito coil was completely burned. Then, from the calculated volatilization amount and the blending amount of the insecticidal component at the time of production, the insecticidal component retention rate was calculated based on the above-described formula (1).

(3) Palatability A long-lasting mosquito coil was burned in a glass cylinder with a diameter of 20 cm and a height of 40 cm, and 10 panelists gave the highest score of 10 and the lowest score of 1 for stimulus relaxation and fragrance 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 long-lasting mosquito coil was burned in the center of a closed 25 m ³ room. Eight hours after burning, 50 adult Culex pipiens females were released and after 2 hours of exposure, all test mosquitoes were collected. During this period, the number of Culex pipiens female adults that fell and turned upside down was counted over time, and the point at which 25 Culex pipiens female adults fell upside down was defined as the KT ₅₀ value (rounded off to the nearest whole number).

The long-lasting mosquito coils of Examples 1 to 12, which contain metofluthrin, profluthrin, or transfluthrin as an insecticidal component and contain a carbonized base material having an iodine adsorption capacity of 200 mg/g or less, have excellent stability over time, All of them have an insecticidal component retention rate of 40% or more, and it was confirmed that the KT ₅₀ value 12 hours after burning is 30 minutes or less even for short-time combustion of 30 minutes or less, and that excellent insecticidal effects can be obtained continuously. rice field. The long-lasting mosquito coils of Examples 1 to 12 have temporal stability equal to or higher than that of the reference example that does not contain a carbide base material having iodine adsorption capacity, and an insecticidal effect 12 hours after burning. Since the iodine adsorption capacity of the carbide substrate is suppressed to 200 mg/g or less, it is considered that excessive decomposition of the insecticidal component by the carbide substrate does not occur.

In addition, the long-lasting mosquito coils of the reference example were concerned about the smell of smoke and the amount of smoke, whereas the long-lasting mosquito coils of Examples 1 to 12 were all after burning. It had a highly palatable fragrance, was not too full of smoke, and was easy to use in practical use because it was excellent in alleviating stimulation and in the palatability of the fragrance. From this, the long-lasting mosquito coils of Examples 1 to 12 have the effect of reducing odors and irritation caused by smoke and the like during combustion even if the iodine adsorption capacity of the carbonized base material is 200 mg / g or less. It is considered to be sufficiently obtained.

Among the long-lasting mosquito coils of Examples 1 to 12, those with a relatively low volatilization amount of the insecticidal component per unit time (Examples 4 to 6 and 8) tended to slightly decrease in efficacy. rice field. In addition, in Example 3, where the volatilization amount per unit time was 10.2 mg/min, which was exceptionally large, the combustion of the persistent mosquito coil did not last until the end in some cases. Therefore, the volatilization amount of the insecticidal component per unit time is preferably 0.05 to 15 mg/minute, more preferably 0.1 to 10 mg/minute.

Compared with Example 1, Example 9 has the same insecticidal component and the amount of the charcoal base material, and differs only in the type of the _fragrance component. There was no significant difference in values. Example 10 differs from Example 1 in that the blending amounts of the insecticidal component and the charcoal base material are the same and the fragrance component is not blended, but the insecticidal component retention rate and 12 hours after burning There was no significant difference in the _KT50 values of From this, it is considered that the type and blending amount of the fragrance component do not have a great effect on the decomposition of the insecticidal component due to the iodine adsorption capacity of the carbide base material.

On the other hand, when methofluthrin is contained as an insecticidal component as in Comparative Examples 1 to 3, but a carbonized substrate having an iodine adsorption capacity of more than 200 mg/g is contained, the insecticidal component has insufficient stability over time. The insecticidal component retention rate was less than ₄₀ %, and the KT50 value 12 hours after burning was 120 minutes or more, indicating that sufficient insecticidal effect was not obtained. This is presumably because the iodine adsorption capacity of the carbide substrate exceeded 200 mg/g, resulting in excessive decomposition of the insecticidal component by the carbide substrate. In addition, in the long-lasting mosquito coils of Comparative Examples 1 to 3, it was difficult to perceive the fragrant properties of the fragrant components, resulting in a perceptible deterioration of the scent tone.

The long-lasting mosquito coil of the present invention can be used for controlling pests as a mosquito coil for home or business use, and is particularly suitable for mosquitoes such as Culex pipiens, Culex pipiens, and Aedes albopictus. be.

Claims (7)

A long-lasting mosquito coil whose insecticidal effect persists even after burning,
one insecticidal component selected from the group consisting of metofruthrin, profluthrin, and transfluthrin;
a plant-derived carbide base material;
contains
The shape is rod-like,
The amount of insecticidal component per incense stick is 6.0 mg or more,
A long-lasting mosquito coil in which the volatilization amount per unit time of the insecticidal component during combustion is set to 0.1 to 15 mg/min. The long-lasting mosquito coil according to claim 1, containing 20 to 80% by weight of the plant-derived carbonized base material. 3. The long-lasting mosquito coil according to claim 1 or 2, wherein said insecticidal effect includes an effect of killing or knocking down pests and/or an pest-repellent effect of keeping pests away. The long-lasting mosquito coil according to any one of claims 1 to 3, wherein the burning time is set within 30 minutes, and the insecticidal effect lasts for 12 hours or more after burning. 5. The long-lasting mosquito coil according to claim 4, which has a KT50 value of 30 minutes or less after 12 hours of burning. The amount of volatilization is determined by burning the long-lasting mosquito coil in an exhaust bell connected to a glass tube filled with silica gel and sucking the air in the exhaust bell with a pump to volatilize the insecticidal component by combustion. The long-lasting mosquito coil according to any one of claims 1 to 5, which is calculated by trapping and analyzing the trapped insecticidal component by gas chromatography. When the compounding amount of the insecticidal component is C _I (mg) and the volatilization amount of the insecticidal component upon complete combustion is V (mg), the following formula (1):
(V/C _I )×100≧40 (1)
The long-lasting mosquito coil according to any one of claims 1 to 6, which is set so as to satisfy