Composition for insect pest control and method for insect pest control

Abstract

Provided is a composition for insect pest control containing natural pyrethrin, a radical chain inhibitor, a peroxide decomposer, and a solvent. Said composition releases natural pyrethrin at a transpiration rate in a range of 0.1 mg / hour to 2.0 mg / hour when heated for 116 hours at 140℃.

Description

Composition for pest control and method for pest control

[0001] The present invention relates to a composition for pest control and a method for pest control. This patent application claims priority and interest under the Paris Convention pursuant to Japanese Patent Application No. 2024-230251 (filed December 26, 2024) and Japanese Patent Application No. 2025-011308 (filed January 27, 2025), the contents of the above applications are incorporated herein by reference in their entirety.

[0002] Due to the growing consumer preference for natural products, natural pyrethrins have attracted attention (for example, Patent Document 1). Natural pyrethrins are suitable for use in pest control, but due to the instability of their chemical structure, their pest control effectiveness may decrease over time or when exposed to high temperatures.

[0003] International Publication No. 2022 / 220294

[0004] The object of this invention is to provide a pest control composition and a pest control method that have excellent pest control effects.

[0005] The inventors, in an effort to find a composition with excellent pest control effects, discovered that a composition containing natural pyrethrin, a radical chain inhibitor, a peroxide decomposer, and a solvent, which evaporates natural pyrethrin at a rate of 0.1 mg / hour to 2.0 mg / hour for 116 hours when heated at 140°C, exhibits excellent pest control effects and ease of use, thus completing the present invention.

[0006] The present invention includes the following [1] to [9]. [1] A pest control composition comprising natural pyrethrin, a radical chain inhibitor, a peroxide decomposer, and a solvent, wherein the natural pyrethrin is evaporated at a rate of 0.1 mg / hour to 2.0 mg / hour for 116 hours by heating at 140°C (hereinafter sometimes referred to as the present invention composition). [2] The pest control composition according to [1], wherein the radical chain inhibitor comprises at least one phenolic antioxidant selected from the group consisting of dibutylhydroxytoluene and butylhydroxyanisole. [3] The pest control composition according to [1] or [2], wherein the peroxide decomposer comprises a phosphorus-based antioxidant having a phenyl group. [4] A pest control composition according to any one of [1] to [3], wherein the peroxide decomposing agent comprises at least one phosphorus-based antioxidant selected from the group consisting of triphenyl phosphite, tetraphenyldipropylene glycol diphosphite, diphenyl mono(2-ethylhexyl) phosphite, di-n-decylphenyl phosphite, diphenyl mono(tridecyl) phosphite, and triisodecyl phosphite. [5] A pest control composition according to any one of [1] to [3], wherein the peroxide decomposing agent comprises triphenyl phosphite. [6] A pest control composition according to any one of [1] to [5], wherein the mass ratio of the radical chain inhibitor to the peroxide decomposing agent is 1:0.010 to 1:8. [7] A pest control composition according to any one of [1] to [6], which is a heat vaporization type pest control preparation. [8] A heat vaporization type insecticide device comprising a liquid bottle filled with the pest control composition according to [7], a liquid absorption wick, and a heating element. [9] A method for controlling pests, comprising the step of evaporating natural pyrethrin into the air at a evaporation rate of 0.1 mg / hour to 2.0 mg / hour for 116 hours.

[0007] The pest control composition and pest control method of the present invention have excellent pest control effects.

[0008] Figure 1 is a cross-sectional view of a heat vaporization type insecticide device using a liquid insecticide bottle.

[0009] The composition of the present invention comprises a natural pyrethrin, a radical chain inhibitor, a peroxide decomposer, and a solvent.

[0010] <Natural Pyrethrins> The natural pyrethrins used in this invention contain six compounds as active ingredients: pyrethrin I, pyrethrin II, cinerin I, cinerin II, jasmoline I, and jasmoline II. Natural pyrethrins can typically be obtained as an extract or dried pyrethrin powder, obtained by extracting the active ingredients from a powder made by collecting, drying, and grinding only the calyx of the flower of chrysanthemum (Tanacetum cinerariifolium or Chrysanthemum cinerariaefolium) using a suitable solvent (also called a solvent), such as an organic solvent like methanol. In addition to the six compounds mentioned above, natural pyrethrins may also contain plant-derived impurities (such as fatty acids and flavonoids).In addition to the aforementioned Chrysanthemum cinerariaefolium, other plants from which natural pyrethrins can be obtained include Calendula officinalis, Chrysanthemum coccinum, Tagetes erecta, Tagetes minuta, Zinnia elegans, and Zinnia linnearis (References 1: Adnane. H. Alain, C. & Chantal, B. 2000. The Production of Pyrethrins by Plant Cell and Tissue Cultures of Chrysanthemum cinerariaefolium and Tagetes Species. Critical Reviews in Plant Sciences, 19(1):69-89; Reference 2: Kudakasseril, GJ and Staba, EJ 1988. Insecticidal phytochemicals. In: Cell Culture and Somatic Cell Genetics of Plants. pp. 537-552. Constabel, F. and Vasil, IK, Eds., Academic Press, New York, Reference 3: John E. Casida, Gary B. Quistad. 1995. PYRETHRUM FLOWERS, Production, Chemistry, Toxicology, and Uses. pp. 123-125, Oxford University Press.).

[0011] The plant species and varieties that serve as the source of natural pyrethrins used in this invention are not limited to those mentioned above. The cultivation methods, cultivation conditions (weather, origin, soil type, etc.), harvest time, harvest part, harvesting method, washing method, extraction method, and purification method of the plants are not particularly limited. Natural pyrethrins used in this invention also include, for example, natural pyrethrins obtained using a vector into which a gene encoding a pyrethrin biosynthesis enzyme is incorporated.

[0012] The mass ratios of the six compounds used in the natural pyrethrins of the present invention—pyrethrin I, pyrethrin II, synerin I, synerin II, jasmolin I, and jasmolin II—are not particularly limited. Any mass ratio can be set for each compound in the range of 0.001 to 99% by mass relative to the total amount of natural pyrethrins. Typically, however, the natural pyrethrins are contained in the following mass ratios: pyrethrin I at 10 to 70% by mass, pyrethrin II at 10 to 70% by mass, synerin I at 1 to 20% by mass, synerin II at 1 to 20% by mass, jasmolin I at 1 to 20% by mass, and jasmolin II at 1 to 20% by mass, relative to the total amount of natural pyrethrins. As a specific example of a mixing ratio (mass ratio), [Pyrethrin I: Synerin I: Jasmolin I: Pyrethrin II: Synerin II: Jasmolin II] = 38.0:7.3:4.0:35.0:11.7:4.0 (Reference 3).

[0013] Examples of natural pyrethrins used in the present invention include pyrethrin I (total amount of pyrethrin I, synerin I, and jasmolin I) and pyrethrin II (total amount of pyrethrin II, synerin II, and jasmolin II), with pyrethrin I at 20 to 40% by mass and pyrethrin II at 12 to 31% by mass relative to the total amount of natural pyrethrin. The total amount of pyrethrin I and pyrethrin II in the natural pyrethrin is usually 10 to 99% by mass, preferably 15 to 90% by mass, and more preferably 20 to 85% by mass, relative to the total amount of natural pyrethrin.

[0014] The content of natural pyrethrin in the composition of the present invention is preferably 0.3 to 1.8% by mass, more preferably 0.4 to 1.5% by mass, relative to the total amount of the composition of the present invention. Even more preferably, it is 0.6 to 1.5% by mass. Specific examples of natural pyrethrin content include 0.3% by mass, 0.4% by mass, 0.5% by mass, 0.6% by mass, 0.7% by mass, 0.8% by mass, 0.9% by mass, 1.0% by mass, 1.1% by mass, 1.2% by mass, 1.3% by mass, 1.4% by mass, 1.5% by mass, 1.6% by mass, 1.7% by mass, and 1.8% by mass. These contents can also be expressed as "approximately." "Approximately" means plus or minus 10%, for example, "approximately 1% by mass" means 0.9% by mass to 1.1% by mass.

[0015] <Radical Chain Inhibitors> The radical chain inhibitors used in the present invention will now be described. In the present invention, a radical chain inhibitor means a compound that reacts with free radicals to produce stable molecules, thereby stopping chain reactions caused by free radicals. Examples of radical chain inhibitors include dibutylhydroxytoluene (hereinafter sometimes abbreviated as BHT) and butylhydroxyanisole (hereinafter sometimes abbreviated as BHA). Among these, BHA is preferred. BHT and BHA may also be used in combination. BHT and BHA are commercially available, for example, from Kanto Chemical Co., Ltd. The content of the radical chain inhibitor in the composition of the present invention is preferably 0.1 to 10% by mass, more preferably 0.2 to 8.0% by mass, and even more preferably 0.25 to 6.0% by mass, based on the total amount of the composition of the present invention. Specific radical chain inhibitor contentes include 0.15% by mass, 0.2% by mass, 0.3% by mass, 0.4% by mass, 0.5% by mass, 0.6% by mass, 0.7% by mass, 0.8% by mass, 0.9% by mass, 1.0% by mass, 2.0% by mass, 3.0% by mass, 4.0% by mass, 5.0% by mass, 6.0% by mass, 7.0% by mass, 8.0% by mass, and 9.0% by mass.

[0016] The mass ratio of natural pyrethrin to radical chain inhibitor contained in the composition of the present invention is preferably 1:0.1 to 1:34, more preferably 1:0.17 to 1:21, and even more preferably 1:0.3 to 1:10. Specific mass ratios include 1:0.2, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19, 1:20, 1:21, 1:22, 1:23, 1:24, 1:25, 1:26, 1:27, 1:28, 1:29, 1:30, 1:31, 1:32, and 1:33. These mass ratios can also be expressed as "approximately". "Approximately" means plus or minus 10%, so for example, "approximately 1:2" means between 1:1.8 and 1:2.2.

[0017] <Peroxide Decomposing Agents> The peroxide decomposing agents used in the present invention will now be described. In the present invention, a peroxide decomposing agent means a compound that has the effect of decomposing peroxides and converting them into more stable compounds. Peroxide decomposing agents include phosphorus-based antioxidants and sulfur-based antioxidants. Phosphorus-based antioxidants can be suitably used as peroxide decomposing agents. Furthermore, phosphorus-based antioxidants having a phenyl group can be suitably used as peroxide decomposing agents. In addition, multiple peroxide decomposing agents may be used in combination. Specific peroxide decomposing agents include, for example, triphenyl phosphite, tetraphenyldipropylene glycol diphosphite, diphenyl mono(2-ethylhexyl) phosphite, di-n-decylphenyl phosphite, diphenyl mono(tridecyl) phosphite, and triisodecyl phosphite. Among these, triphenyl phosphite, tetraphenyldipropylene glycol diphosphite, diphenyl mono(2-ethylhexyl) phosphite, and di-n-decylphenyl phosphite are preferred, and triphenyl phosphite is more preferred. Triphenyl phosphite (CAS registration number: 101-02-0) is commercially available, for example, as triphenyl phosphite (manufactured by Tokyo Chemical Industry Co., Ltd.) or ADEKA stub TPP (manufactured by ADEKA). Tetraphenyldipropylene glycol diphosphite (CAS registration number: 80584-85-6) is commercially available, for example, as JPP-100 (trade name) (manufactured by Johoku Chemical Industry Co., Ltd.). Diphenyl mono(2-ethylhexyl) phosphite (CAS registration number: 15647-08-2) is commercially available, for example, as JPM-308 (trade name) (manufactured by Johoku Chemical Industry Co., Ltd.). Di-n-decylphenyl phosphite (CAS registration number: 1254-78-0) is commercially available from many suppliers (for example, Shaanxi Dideu Medichem). Diphenyl mono(tridecyl) phosphite (CAS registration number: 60628-17-3) is commercially available, for example, as JPM-313 (trade name) (manufactured by Johoku Chemical Industry Co., Ltd.). Triisodecyl phosphite (CAS registration number: 25448-25-3) is commercially available, for example, as ADEKA Stab 3010 (manufactured by ADEKA).The content of the peroxide decomposing agent in the composition of the present invention is preferably 0.1 to 2.0% by mass, more preferably 0.2 to 1.0% by mass, and even more preferably 0.2 to 0.6% by mass, based on the total amount of the composition of the present invention. Specific peroxide decomposing agent contentes include 0.1% by mass, 0.2% by mass, 0.3% by mass, 0.4% by mass, 0.5% by mass, 0.6% by mass, 0.7% by mass, 0.8% by mass, 0.9% by mass, 1.0% by mass, 1.1% by mass, 1.2% by mass, 1.3% by mass, 1.4% by mass, 1.5% by mass, 1.6% by mass, 1.7% by mass, 1.8% by mass, 1.9% by mass, and 2.0% by mass.

[0018] The mass ratio of natural pyrethrin to peroxide decomposing agent contained in the composition of the present invention is preferably 1:0.05 to 1:7, more preferably 1:0.1 to 1:2.5, and even more preferably 1:0.1 to 1:1. Specific mass ratios of natural pyrethrin to peroxide decomposing agent include 1:0.06, 1:0.07, 1:0.08, 1:0.09, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:2, 1:3, 1:4, 1:5, and 1:6.

[0019] The mass ratio of the radical chain inhibitor to the peroxide decomposer contained in the composition of the present invention is preferably 1:0.01 to 1:8, more preferably 1:0.02 to 1:4, and even more preferably 1:0.03 to 1:2. Specific mass ratios of the radical chain inhibitor to the peroxide decomposer include 1:0.02, 1:0.03, 1:0.04, 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.5, 1:2.5, 1:3, 1:4, 1:5, 1:6, and 1:7.

[0020] <Solvents> The solvents used in this invention will now be described. As solvents (also called solvents), oily solvents or aqueous solvents are used. When oily solvents are used, oily solvents with a boiling point of 350°C or lower are usually used. Various organic solvents, mainly hydrocarbon solvents, can be used as such oily solvents, but aliphatic hydrocarbon solvents (paraffinic solvents or unsaturated aliphatic hydrocarbon solvents, or mixtures thereof) with a boiling point range of 150 to 350°C are particularly preferred. Examples of such solvents include paraffinic solvents such as n-paraffin and isoparaffin; deodorizing kerosene; and sewing machine oil (for example, Sewing Lube (manufactured by ENEOS Corporation)), with paraffinic solvents being particularly preferred. Examples of paraffinic solvents include, for example, Solvent No. 0 H (manufactured by ENEOS Corporation), Solvent No. 0 M (manufactured by ENEOS Corporation), Solvent No. 0 L (manufactured by ENEOS Corporation), IP Solvent 2028 (manufactured by Idemitsu Kosan Co., Ltd.), Norper 12 (manufactured by ExxonMobil Corporation), Norper 13 (manufactured by ExxonMobil Chemicals, Inc.), Norper 15 (manufactured by ExxonMobil Corporation), Isopar M (manufactured by ExxonMobil Corporation), Isopar L (manufactured by ExxonMobil Corporation), Isopar V (manufactured by ExxonMobil Corporation), and Isopar G (manufactured by ExxonMobil Corporation). Examples of organic solvents other than the hydrocarbon-based solvents include glycerin, propylene glycol, methanol, acetone, xylene, chlorcene, isopropanol, and chloroform. When aqueous solvents are used, glycol ether and water are usually used. Examples of such glycol ethers include ethylene glycol ethers, propylene glycol ethers, and dialkyl glycol ethers, with ethylene glycol ethers being preferred. Among ethylene glycol ethers, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol monopropyl ether are preferred. Note that one or a mixture of two or more glycol ethers may be used.The mass ratio of glycol ether to water is usually in the range of 1:0.4 to 1:8.5, preferably in the range of 1:1 to 1:8.5, and more preferably in the range of 1:1.4 to 1:3.6. The solvent may further contain an auxiliary solvent (also called an auxiliary solvent), and examples of auxiliary solvents include diisopropyl adipate, diisodecyl adipate, diisobutyl adipate, isopropyl myristate, isopropanol, benzyl acetate, ethanol, sucrose fatty acid ester, sorbitan fatty acid ester, propylene carbonate, 1,3-butylene glycol, polyoxyethylene hydrogenated castor oil, etc. A solvent different from the solvent used may be selected as the auxiliary solvent. For example, when a paraffinic solvent is used as the solvent, diisopropyl adipate or isopropyl myristate is preferred as the auxiliary solvent. The solvent content in the composition of the present invention (including the amount of auxiliary solvent if an auxiliary solvent is included) is preferably 60 to 99.5% by mass, and more preferably 70 to 99% by mass, based on the total amount of the composition of the present invention. Specific solvent content (including the amount of the auxiliary solvent if it includes the auxiliary solvent) is 61% by mass, 62% by mass, 63% by mass, 64% by mass, 65% by mass, 66% by mass, 67% by mass, 68% by mass, 69% by mass, 70% by mass, 71% by mass, 72% by mass, 73% by mass, 74% by mass, 75% by mass, 76% by mass, 77% by mass. , 78 mass%, 79 mass%, 80 mass%, 81 mass%, 82 mass%, 83 mass%, 84 mass%, 85 mass%, 86 mass%, 87 mass%, 88 mass%, 89 mass%, 90 mass%, 91 mass%, 92 mass%, 93 mass%, 94 mass%, 95 mass%, 96 mass%, 97 mass%, 98 mass%, 99 mass%. If the composition of the present invention further contains an auxiliary solvent, the content of the auxiliary solvent is usually 5 to 35% by mass, preferably 10 to 30% by mass, and more preferably 10 to 20% by mass, based on the total amount of the composition of the present invention.Specific examples of auxiliary solvent content include 6% by mass, 7% by mass, 8% by mass, 9% by mass, 10% by mass, 11% by mass, 12% by mass, 13% by mass, 14% by mass, 15% by mass, 16% by mass, 17% by mass, 18% by mass, 19% by mass, 20% by mass, 21% by mass, 22% by mass, 23% by mass, 24% by mass, 25% by mass, 26% by mass, 27% by mass, 28% by mass, 29% by mass, 30% by mass, 31% by mass, 32% by mass, 33% by mass, and 34% by mass. When the composition of the present invention further contains an auxiliary solvent, the content of the solvent excluding the auxiliary solvent is usually 51 to 94% by mass, preferably 60 to 89% by mass, and more preferably 72 to 88% by mass, relative to the total amount of the composition of the present invention. The content of the solvent excluding the specific auxiliary solvent is 52% by mass, 53% by mass, 54% by mass, 55% by mass, 56% by mass, 57% by mass, 58% by mass, 59% by mass, 60% by mass, 61% by mass, 62% by mass, 63% by mass, 64% by mass, 65% by mass, 66% by mass, 67% by mass, 68% by mass, 69% by mass, 70% by mass, 71% by mass. %, 72 mass%, 73 mass%, 74 mass%, 75 mass%, 76 mass%, 77 mass%, 78 mass%, 79 mass%, 80 mass%, 81 mass%, 82 mass%, 83 mass%, 84 mass%, 85 mass%, 86 mass%, 87 mass%, 88 mass%, 89 mass%, 90 mass%, 91 mass%, 92 mass%, 93 mass%.

[0021] The composition of the present invention may also contain other formulation aids, such as other insecticidal active ingredients, thickeners, surfactants, stabilizers, preservatives, essential oils, or synergists, to the extent that they do not adversely affect the evaporation rate of natural pyrethrins.

[0022] The compositions of the present invention can be obtained, for example, by mixing natural pyrethrin, a radical chain inhibitor, a peroxide decomposer, a solvent, and optionally a formulation aid until homogeneous.

[0023] In one aspect of the present invention, the composition of the present invention comprises natural pyrethrin, at least one radical chain inhibitor selected from the group consisting of BHT and BHA, at least one peroxide decomposer selected from the group consisting of triphenyl phosphite, tetraphenyldipropylene glycol diphosphite, diphenylmono(2-ethylhexyl) phosphite, din-decylphenyl phosphite, diphenylmono(tridecyl) phosphite, and triisodecyl phosphite, and at least one solvent selected from the group consisting of isoparaffin, diisopropyl adipate, and isopropyl myristate.

[0024] In one aspect of the present invention, the composition of the present invention comprises natural pyrethrin, at least one radical chain inhibitor selected from the group consisting of BHT and BHA, at least one peroxide decomposer selected from phosphorus-based antioxidants having a phenyl group, and at least one solvent selected from the group consisting of isoparaffin, diisopropyl adipate, and isopropyl myristate.

[0025] In one aspect of the present invention, the composition of the present invention comprises natural pyrethrin, BHA, triphenyl phosphite, isoparaffin, and diisopropyl adipate.

[0026] <Evaporation rate> By heating the composition of the present invention at 140 °C, natural pyrethrin is evaporated in the range of an evaporation rate of 0.1 mg / hour to 2.0 mg / hour for 116 hours. By making a composition containing natural pyrethrin, a radical chain inhibitor, a peroxide decomposer, and a solvent, it is possible to adjust the evaporation of natural pyrethrin at a desired rate.

[0027] In this invention, the evaporation rate of natural pyrethrin after heating for X hours means the mass (mg / hour) of natural pyrethrin that evaporates per hour during a total heating time of X hours to X+1 hours. That is, for example, the evaporation rate of natural pyrethrin after heating for 10 hours means the mass (mg / hour) of natural pyrethrin that evaporates per hour during a total heating time of 10 to 11 hours. The evaporation rate after heating at 140°C for 116 hours is measured, for example, by the following method: A composition prepared by mixing natural pyrethrin, a radical chain inhibitor, a peroxide decomposer, and a solvent is filled into a 45 mL liquid mosquito repellent bottle, an inner stopper with an absorbent wick (made of wood powder, φ7 mm, length 72 mm) inserted is attached, and the system is energized (heated) for a total of 14 days (112 hours), with "8 hours of power on - 4 hours of OFF" set as equivalent to one day of use. Subsequently, the mass (mg / hour) of natural pyrethrin evaporated per hour during the 4-5 hours after the start of power supply on the 15th day is analyzed. The evaporation rate (mg / hr) of natural pyrethrin is determined by collecting the evaporated natural pyrethrin vapor in a urethane foam-packed column for a predetermined time, extracting it with acetone, and quantitatively analyzing the natural pyrethrin contained in the extract by high-performance liquid chromatography. The evaporation rate at other time points can be measured in the same manner.

[0028] In another embodiment of the present invention, it can be a composition that evaporates natural pyrethrin in the range of an evaporation rate of 0.1 mg / hour to 2.0 mg / hour for 164 hours by heating at 140°C. In another embodiment of the present invention, it can be a composition that evaporates natural pyrethrin in the range of an evaporation rate of 0.1 mg / hour to 2.0 mg / hour for 228 hours by heating at 140°C. In one embodiment of the present invention, the ratio (V116 / V4) of the evaporation rate (V116) of natural pyrethrin after heating at 140°C for 116 hours to the evaporation rate (V4) of natural pyrethrin after heating at 140°C for 4 hours can be 0.1 to 3.0. Specific ratios (V116 / V4) include, for example, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9.

[0029] One embodiment of the present invention is a composition containing 0.3 to 1.8% by mass of natural pyrethrin, 0.1 to 10% by mass of a radical chain inhibitor, 0.1 to 2.0% by mass of a peroxide decomposer, and 60 to 99.5% by mass of a solvent, which evaporates natural pyrethrin in the range of an evaporation rate of 0.1 mg / hour to 2.0 mg / hour for 116 hours by heating at 140°C. Another embodiment of the present invention is a composition containing 0.3 to 1.8% by mass of natural pyrethrin, 0.1 to 10% by mass of BHA, 0.1 to 2.0% by mass of triphenyl phosphite, and 60 to 99.5% by mass of a solvent, which evaporates natural pyrethrin in the range of an evaporation rate of 0.1 mg / hour to 2.0 mg / hour for 116 hours by heating at 140°C.

[0030] The composition of the present invention is preferably used as a heating evaporation type pest control preparation.

[0031] <Heat-Vaporized Insecticide Preparation> The heat-vaporized insecticide preparation according to one embodiment of the present invention is a preparation that can be used in a heat-vaporized insecticide device 100, such as the one shown in Figure 1. The heat-vaporized insecticide preparation (solution 1) is filled into a liquid bottle 4. A portion of the liquid-absorbing wick 3 is immersed in the solution 1, and the liquid-absorbing wick is made to absorb the heat-vaporized insecticide preparation, and the upper part of the liquid-absorbing wick can be heated by a heating element 2 (the heating element is also called a heat-generating element). By indirectly heating the upper part of the liquid-absorbing wick to a temperature of about 60°C to about 150°C with the heating element 2, the natural pyrethrin contained in the heat-vaporized insecticide preparation absorbed by the liquid-absorbing wick is vaporized into the atmosphere, thereby controlling pests. The heat-vaporized insecticide preparation according to one embodiment of the present invention is not limited to the device shown in Figure 1, but can be applied to conventionally known heat-vaporized insecticide devices, and both can produce excellent effects. A heat-vaporation type insecticide apparatus to which the heat-vaporation insecticide formulation of the present invention can be applied is also described in, for example, Japanese Patent Publication No. 52-12106, Japanese Utility Model Publication No. 58-45670, and Japanese Patent Publication No. 2012-176947.

[0032] While heating elements (heating element 2) that generate heat when electricity is applied are commonly used as heating elements (heating element 2) in heat vaporization type insecticide devices, the device is not limited to these, and any known heating element such as an air oxidation heating element or a heating element utilizing a platinum catalyst can be used.

[0033] The liquid-absorbing core 3 is generally classified into fired cores, porous ceramic cores, resin cores, felt cores, braided cores, and adhesive cores. In the present invention, fired cores, porous ceramic cores, resin cores, and felt cores are preferably used, and fired cores or porous ceramic cores are more preferably used. The material of the fired core is not particularly limited, as long as it is stable to heat-evaporative insect control formulations and capable of absorbing the solution by capillary action. The fired core is obtained by firing a mixture containing (a) an inorganic substance (inorganic powder, inorganic binder, etc.), or preferably (b) an organic substance (carbonaceous powder, organic binder, etc.) at 600 to 2000°C. Here, there are also fired cores that consist almost entirely of (a) with a small amount of (b), and such fired cores are sometimes called porous ceramic cores. The inorganic substance contains inorganic powder as an essential component, but may also contain an inorganic binder as an auxiliary component as needed. Examples of inorganic powders include steatite, alumina, silica, talc, calcite, perlite, mullite, cordierite, mica, zirconia, diatomaceous earth, gypsum, acid clay, fiberglass, and asbestos. Examples of inorganic binders include various clays such as clay (kaolin clay), bentonite, and halosite, as well as tar pitch and water glass. Of these, clay is a preferred material because of its excellent binding properties. The above inorganic binders may be used individually or in a mixture of multiple types. Examples of organic substances include carbonaceous powders such as wood flour, activated carbon, charcoal, diatomaceous earth, graphite, carbon black, and coke, or organic binders such as carboxymethylcellulose (CMC), acrylic resin, polyolefin resin, starch (pregelatinized starch, etc.), gum arabic, gelatin, and polyvinyl alcohol. The resin core is formed by covering the outer surface of the core material with a sheath material for absorbing and vaporizing a heat-dispersing insect control agent. For example, it can be formed from thermoplastic and / or thermosetting synthetic resins having a heat resistance of 130°C or higher, such as synthetic fibers like polyester and nylon, inorganic fibers, or plastic materials like polyethylene, polypropylene, polyvinyl chloride, polyacrylic, and phenolic resin.The sheath material that forms the inside of the core material is usually formed as a fiber aggregate, and the fibers that make up this include felt, cotton, pulp, nonwoven fabric, asbestos, inorganic molded products, as well as synthetic fibers such as polyester and highly absorbent wood. The liquid-absorbing core may also contain dyes, preservatives, or antioxidants as appropriate, for example, by mixing them during the bonding of the inorganic powder and the adhesive. Commercially available liquid-absorbing cores can be used, and examples of such commercially available liquid-absorbing cores include Fuji-Chem HK-100 (manufactured by Fuji Chemical Co., Ltd.) and Rauschert Steatite 45% (manufactured by Rauschert).

[0034] One of the physical properties of an absorbent wick is porosity (= {1 - [bulk density / true density]} × 100), and this value is known to be related to the absorption height due to capillary action of the solution (Gypsum & Lime No. 213 (1988)). In calculating the porosity, the bulk density (g / mL) can be obtained, for example, by dividing the sample weight (unit: g) by the sample volume (c) (unit: mL). The sample volume (c) can be measured, for example, using a mercury intrusion porosimeter as follows: The "total volume of the cell" is determined by filling a sealed measuring cell with mercury. Next, the "cell volume excluding the sample" is determined by filling the sealed measuring cell with mercury at low pressure with the sample inside. The sample volume (c) is calculated by taking the difference between the "total volume of the cell" and the "cell volume excluding the sample". In calculating the porosity, the true density can be determined by the following formula. True density (e) = weight of sample ÷ (sample bulk volume (c) - sample pore volume (d)) The method for measuring the sample bulk volume (c) is as described above. The sample pore volume (d) can be measured, for example, using a mercury intrusion porosimeter as follows: Mercury is injected into a sealed cell containing the sample up to the upper limit of the measurement pressure range, and the cumulative pore volume (f) (unit: mL / g) of the sample is determined from the mercury volume obtained. Then, the sample pore volume (d) (mL) is obtained by multiplying the obtained cumulative pore volume (f) (unit: mL / g) of the sample by the weight of the sample (g). Porosity of the liquid-absorbing wick used in the present invention can be, for example, 30 to 70%. Among these, 40 to 70% is preferred, and 45 to 60% is more preferred. Specific porosity levels include 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 41%, 42%, 43%, 44%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, and 69%.

[0035] Furthermore, the cumulative pore volume (mL / g) is known as a physical property of the liquid-absorbing wick. The cumulative pore volume can be determined by the measurement method using the mercury intrusion porosimeter described above. Examples of the cumulative pore volume of the liquid-absorbing wick used in the present invention include 0.1 to 2.0 mL / g, preferably 0.2 to 1.5 mL / g, and more preferably 0.4 to 1.0 mL / g. Specific cumulative pore volumes include 0.1 mL / g, 0.2 mL / g, 0.3 mL / g, 0.4 mL / g, 0.5 mL / g, 0.6 mL / g, 0.7 mL / g, 0.8 mL / g, 0.9 mL / g, 1.0 mL / g, 1.1 mL / g, 1.2 mL / g, 1.3 mL / g, 1.4 mL / g, 1.5 mL / g, 1.6 mL / g, 1.7 mL / g, 1.8 mL / g, 1.9 mL / g, and 2.0 mL / g.

[0036] Furthermore, the pore size (μm) is known as a physical property of the liquid-absorbing wick. The pore size can be measured, for example, using a mercury intrusion porosimeter. The pore size distribution can be obtained from the relationship between the pore size and its volume obtained using a mercury intrusion porosimeter. Furthermore, by taking the logarithmic derivative (dV) of the increase in pore volume between measurement points and dividing it by the logarithm of the difference in pore size (dlogD) (mL / g) on ​​the vertical axis, and examining the relationship with the logarithm of the pore size (μm), the maximum pore size into which the most mercury has penetrated can be read. Examples of the maximum pore size of the liquid-absorbing wick used in this invention include 0.2 to 10 μm, preferably 0.5 to 8 μm, and more preferably 0.8 to 5 μm. Specific examples of maximum pore diameters include 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, and 10 μm.

[0037] In a heat vaporization type insecticide device according to one embodiment of the present invention, the distance between the heating element and the liquid-absorbing wick may be 1 mm to 10 mm. Specific distances between the heating element and the liquid-absorbing wick include 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, and 10 mm. If the distance from the heating element to the liquid-absorbing wick varies depending on the location, the above distance shall be the average value of 10 points of the distance from the heating element to the liquid-absorbing wick (distance measured to be the shortest distance from a predetermined point on the heating element).

[0038] In the heat-evaporation type insecticidal device according to one embodiment of the present invention, the surface area of the liquid absorption core directly heated by the heating body (the area of the surface of the liquid absorption core facing the heating body) is 0.5 to 10 cm

[0039] , 2 , 2 , 2 , 2 , 2 , , 2 , 2 , 2 It can be. Specific examples of the surface area of the liquid absorption core directly heated by the heating body include 0.6 cm 2 、0.7 cm 2 、0.8 cm 2 、0.9 cm 2 、1.0 cm 2 、1.1 cm 2 、1.2 cm 2 、1.3 cm 2 、1.4 cm 2 、1.5 cm 2 、1.6 cm 2 、1.7 cm 2 、1.8 cm 2 、1.9 cm 2 、2.0 cm 2 、2.1 cm 2 、2.2 cm 2 、2.3 cm 2 、2.4 cm 2 、2.5 cm 2 、2.6 cm 2 、2.7 cm 2 、2.8 cm 2 、2.9 cm 2 、3.0 cm 2 、3.5 cm 2 、4.0 cm 2 、4.5 cm 2 、5.0 cm 2 、5.5 cm 2 、6.0 cm 2 、6.5 cm 2 、7.0 cm 2 、7.5 cm 2 、8.0 cm 2 、8.5 cm 2 、9.0 cm 2 、9.5 cm 2 can be mentioned.

[0039] One parameter that can be considered when designing a heat vaporization type insecticide device is the "percentage of chemical solution reduction during a predetermined total heating time," defined by the following formula: Percentage of chemical solution reduction during a predetermined heating time (%) = (1 - Mass of heat vaporization insecticide remaining in the bottle during the predetermined total heating time (g) / Mass of initial heat vaporization insecticide filled in the bottle (g)) × 100 The percentage of chemical solution reduction during a predetermined total heating time can be set according to the intended usage period of the heat vaporization type insecticide device. For example, when manufacturing a heat vaporization type insecticide device with a long usage period, it can be designed so that the percentage of chemical solution reduction during a predetermined heating time is low. The percentage of chemical solution reduction during a predetermined total heating time can be adjusted by appropriately selecting the physical properties of the liquid absorption wick and the amount of heat vaporization insecticide filled into the chemical solution bottle.

[0040] A heat vaporization type insecticide device according to one embodiment of the present invention may be designed such that the rate of reduction of the insecticide solution over a total heating time of 160 hours is 40 to 80%, and the rate of reduction of the insecticide solution over a total heating time of 360 hours is 60 to 100%.

[0041] Another embodiment of the present invention may be a heat vaporization type insecticide device designed such that the rate of reduction of the insecticide solution over a total heating time of 360 hours is 30 to 80%, and the rate of reduction of the insecticide solution over a total heating time of 720 hours is 50 to 100%.

[0042] A heat vaporization insecticide device according to one embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 0.6 parts by mass of natural pyrethrin (as active ingredient), 1.0 part by mass of BHA, 0.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and a 4:6 (mass ratio) mixed solvent of Isopar M and Isopar L in an amount necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 55% and a cumulative pore volume of 0.85 mL / g is used. The temperature of the heating element is set to 140°C. The liquid reduction rate after a total heating time of 160 hours is 75%, and the liquid reduction rate after a total heating time of 320 hours is 100%.

[0043] A heat vaporization insecticide device of another embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 0.6 parts by mass of natural pyrethrin (as active ingredient), 1.0 part by mass of BHA, 0.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and a 4:6 (mass ratio) mixed solvent of Isopar M and Isopar L in amounts necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 49% and a cumulative pore volume of 0.51 mL / g is used. The temperature of the heating element is set to 140°C. The rate of liquid reduction after a total heating time of 160 hours is 48%, and the rate of liquid reduction after a total heating time of 360 hours is 74%.

[0044] A heat vaporization insecticide device of another embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 0.6 parts by mass of natural pyrethrin (as active ingredient), 1.0 part by mass of BHA, 0.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and a 4:6 (mass ratio) mixed solvent of Isopar M and Isopar L in amounts necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 41% and a cumulative pore volume of 0.24 mL / g is used. The temperature of the heating element is set to 140°C. The rate of reduction of the liquid solution over a total heating time of 360 hours is 64%.

[0045] A heat vaporization insecticide device of another embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 0.6 parts by mass of natural pyrethrin (as active ingredient), 5.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and a 4:6 (mass ratio) mixed solvent of Isopar M and Isopar L in amounts necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 55% and a cumulative pore volume of 0.85 mL / g is used. The temperature of the heating element is set to 140°C. The liquid reduction rate after a total heating time of 160 hours is 65%, after a total heating time of 357 hours it is 99%, and after a total heating time of 360 hours it is 100%.

[0046] A heat vaporization insecticide device of another embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 0.6 parts by mass of natural pyrethrin (as active ingredient), 5.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and a 4:6 (mass ratio) mixed solvent of Isopar M and Isopar L in an amount necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 49% and a cumulative pore volume of 0.51 mL / g is used. The temperature of the heating element is set to 140°C. The rate of liquid reduction after a total heating time of 160 hours is 51%, after a total heating time of 357 hours it is 72%, and after a total heating time of 480 hours it is 83%.

[0047] A heat vaporization insecticide device of another embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 0.6 parts by mass of natural pyrethrin (as active ingredient), 5.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and a 4:6 (mass ratio) mixed solvent of Isopar M and Isopar L in an amount necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 41% and a cumulative pore volume of 0.24 mL / g is used. The temperature of the heating element is set to 140°C. The rate of liquid reduction after a total heating time of 160 hours is 49%, after a total heating time of 357 hours it is 71%, and after a total heating time of 480 hours it is 80%.

[0048] A heat vaporization insecticide device of another embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 0.4 parts by mass of natural pyrethrin (as active ingredient), 1.0 part by mass of BHA, 5.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and the amount of isopar L necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 41% and a cumulative pore volume of 0.24 mL / g is used. The temperature of the heating element is set to 140°C. The rate of liquid reduction after a total heating time of 164 hours is 56%, after a total heating time of 277 hours it is 75%, and after a total heating time of 376 hours it is 88%.

[0049] A heat vaporization insecticide device of another embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 0.6 parts by mass of natural pyrethrin (as active ingredient), 1.0 part by mass of BHA, 5.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and an amount of isopar L necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 41% and a cumulative pore volume of 0.24 mL / g is used. The temperature of the heating element is set to 140°C. The rate of liquid reduction after a total heating time of 164 hours is 43%, after a total heating time of 277 hours it is 55%, and after a total heating time of 376 hours it is 63%.

[0050] A heat vaporization insecticide device of another embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 1.2 parts by mass of natural pyrethrin (as active ingredient), 1.0 part by mass of BHA, 5.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and the amount of isopar L necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 41% and a cumulative pore volume of 0.24 mL / g is used. The temperature of the heating element is set to 140°C. The rate of liquid reduction after a total heating time of 164 hours is 33%, after a total heating time of 277 hours it is 40%, and after a total heating time of 376 hours it is 44%.

[0051] A heat vaporization insecticide device of another embodiment of the present invention may be configured as follows: The heat vaporization insecticide preparation consists of 1.5 parts by mass of natural pyrethrin (as active ingredient), 1.0 part by mass of BHA, 5.06 parts by mass of BHT, 0.5 parts by mass of triphenyl phosphite, 15 parts by mass of diisopropyl adipate, and an amount of isopar L necessary to make 100 parts by mass of the preparation. 45 mL of the heat vaporization insecticide preparation is filled into a liquid bottle. A liquid-absorbing wick with a porosity of 41% and a cumulative pore volume of 0.24 mL / g is used. The temperature of the heating element is set to 140°C. The rate of liquid reduction after a total heating time of 164 hours is 28%, after a total heating time of 277 hours it is 33%, and after a total heating time of 376 hours it is 36%.

[0052] One embodiment of the present invention is a pest control method comprising the step of heating a heat-evaporative insecticide formulation to vaporize natural pyrethrin into the air for 116 hours at an evaporation rate in the range of 0.1 mg / hour to 2.0 mg / hour. One embodiment of the present invention is a pest control method comprising the step of heating a heat-evaporative insecticide formulation to vaporize natural pyrethrin into the air for 164 hours at an evaporation rate in the range of 0.1 mg / hour to 2.0 mg / hour. One embodiment of the present invention is a pest control method comprising the step of heating a heat-evaporative insecticide formulation to vaporize natural pyrethrin into the air for 228 hours at an evaporation rate in the range of 0.1 mg / hour to 2.0 mg / hour. In one embodiment of the present invention, the ratio (R116 / R4) of the transpiration rate of natural pyrethrin 4 hours after the start of transpiration (R4) (per hour from 4 to 5 hours after the start of transpiration) to the transpiration rate of natural pyrethrin 116 hours after the start of transpiration (R116) (per hour from 116 to 117 hours after the start of transpiration) can be 0.1 to 3.0. Specific ratios (R116 / R4) include, for example, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, and 2.9. Another embodiment of the present invention is a method of controlling pests in which the heating of the heat-evaporative insect control agent is performed by allowing an absorbent core to absorb the heat-evaporative insect control agent and heating the upper part of the absorbent core with a heating element. Another embodiment of the present invention is a method for controlling pests in which the upper part of the liquid-absorbing wick is heated with a heating element to indirectly heat the upper part of the liquid-absorbing wick to a temperature of approximately 60°C to approximately 150°C (for example, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C).A further embodiment of the present invention is a method for controlling pests, wherein the space from which the natural pyrethrin is evaporated includes at least one selected from entrances, corridors, toilets, washrooms, bathrooms, changing rooms, verandas, balconies, attics, stairs, garages, warehouses, attic storage, pantries, libraries, closets, cupboards, living rooms, bedrooms, dining rooms, and outdoors (e.g., gardens, yards, campgrounds, sports fields, forests).

[0053] The pests that can be controlled by the composition and pest control method of the present invention include various harmful insects and arthropods such as mites. Specifically, the pests that can be controlled include harmful flying insects such as Culex pipiens, Culex tritaeniorhynchus, Culex aeruginosa, and Culex pipiens; Aedes mosquitoes such as Aedes aegypti and Aedes albopictus; Anopheles mosquitoes such as Anopheles sinensis; midges; houseflies such as Muscicapa japonica, Muscicapa fuscipes, and Muscicapa japonica; blowflies, flesh flies, Drosophila, moth flies, phorid flies, horseflies, gnats, stable flies, and biting midges. Among these, mosquitoes such as Culex pipiens, Aedes mosquitoes, and Anopheles mosquitoes are particularly suitable as pests to be controlled. Furthermore, the composition and pest control method of the present invention are also effective against mosquitoes, flies, fleas, bed bugs, house dust mites, indoor dust mites, cockroaches, ticks, and other sanitary pests that are classified as sanitary pests that transmit diseases and cause illness in humans, and these sanitary pests can also be listed as target pests for control.

[0054] Another embodiment of the present invention is a method for controlling pests, wherein the method for controlling pests is a method for exterminating sanitary pests. In this specification, "control" is a concept that includes extermination, repellent, and prevention. "Extermination" is a concept that includes killing, knocking down, driving away, or keeping away the target pest, and it is preferable to kill or knock down the pest.

[0055] The present invention will be described in more detail below with reference to examples such as manufacturing examples and test examples, but the present invention is not limited to these examples.

[0056] Manufacturing Example 1 (Manufacturing of a heat-dispersion insecticide) A heat-dispersion insecticide of Example 1 was obtained by mixing natural pyrethrin, a radical chain inhibitor, a peroxide decomposer, and a solvent to obtain the composition of Formulation Example 1 shown in Table 1. A heat-dispersion insecticide of Comparative Example 1 was obtained by mixing natural pyrethrin, a radical chain inhibitor, and a solvent to obtain the composition of Comparative Example 1 shown in Table 1.

[0057] In the table, radical chain inhibitor 1: BHA; radical chain inhibitor 2: BHT; peroxide decomposition agent 1: triphenyl phosphite (ADEKA TPP (ADEKA)); solvent 1: diisopropyl adipate; solvent 2: a mixed solvent of Isopar M and Isopar L in a 4:6 (mass ratio) ratio (Isopar M (trade name) and Isopar L (trade name) are both isoparaffinic solvents manufactured by ExxonMobil).

[0058] Test Example 1 (Amount of Natural Pyrethrin Evaporated in Heat-Dispersing Insecticide Formulations) 34 g of the heat-dispersing insecticide formulation of Formulation Example 1 or Comparative Formulation Example 1 was filled into a 45 mL plastic container, and a porous liquid-absorbing wick (cylindrical, diameter: 7 mm, length: 72 mm, porosity: 55%, cumulative pore volume: 0.85 mL / g, maximum pore diameter: 4 μm, wood powder liquid-absorbing wick obtained by calcining wood powder and binder, etc.) was inserted via a stopper so that the top could be heated by a heater, thus creating a heat-dispersing insecticide formulation with a liquid-absorbing wick. The heat-dispersing insecticide formulation with a liquid-absorbing wick was set in the heat-dispersing insecticide device (heater temperature: 140°C) shown in Figure 1. After turning the heater ON for 8 hours (heating), turning the power OFF for 4 hours (heating stop) constituted one cycle, and this was repeated. In specific cycles from the start of heating to cycle 15, the amount of natural pyrethrin evaporated per hour at 4-5 hours after the start of heating was measured. The test was performed in two replicates, and the amount of natural pyrethrin evaporated was taken as the average of the two measurements. The amount of natural pyrethrin evaporated was determined by collecting the evaporated natural pyrethrin over time using a glass column packed with polyurethane sponge as an adsorbent, then extracting it from the polyurethane sponge with acetone, and quantitatively analyzing the amount of natural pyrethrin in the extract using high-performance liquid chromatography (absolute calibration curve method). The results are shown in Table 2.

[0059] The heat-dispersed insecticide formulation in Formulation Example 1 was confirmed to maintain a natural pyrethrin evaporation rate of 0.1 to 2.0 mg / hour over a long period of time. On the other hand, the heat-dispersed insecticide formulation in Comparative Formulation Example 1 had a low natural pyrethrin evaporation rate per hour.

[0060] Test Example 2 (Efficacy Test of Heat-Dispersed Insecticide Formulation) Ten female adult Culex pipiens pallens mosquitoes were placed in a glass tube with a diameter of 4.5 cm and a height of 12 cm, and the openings at the top and bottom of the glass tube were covered with nylon netting to contain them. The same procedure was repeated to prepare two glass tubes containing 10 female adult Culex pipiens mosquitoes each. A metal cylinder with a diameter of 22 cm and a height of 83 cm was set upright. The two glass tubes containing the Culex pipiens mosquitoes were fixed vertically above the metal cylinder so that the lower end of the glass tubes was at the height of the upper opening of the metal cylinder. The heat-dispersed insecticide formulation of Formulation Example 1 (filled in a bottle with an absorbent wick inserted), which had been heated for a predetermined period, was set in the heat-dispersed insecticide device (heater temperature: 140°C) shown in Figure 1. The heat vaporization insecticide device was installed at the bottom inside a metal cylinder, and the knockdown rate was recorded after 10 minutes of being powered on (heating). The same procedure was performed using the heat vaporization insecticide of Comparative Formulation Example 1 instead of Formulation Example 1. The knockdown rate (hereinafter referred to as the KD rate) can be calculated using the following formula: KD rate (%) = (number of knocked-down insects / number of test insects) × 100. The results are shown in Table 3.

[0061]

[0062] Test Example 3 (User Experience of Heat-Vaporized Insecticide) One or more heat-vaporized insecticide devices, as shown in Figure 1, were set on the floor of a test chamber (3m x 4m x 2.3m) to produce a predetermined amount of natural pyrethrin vaporization. The natural pyrethrin was vaporized by turning on the power (heating) for 10 minutes. After that, participants entered the chamber and evaluated the user experience by assigning scores based on the following criteria. The results are shown in Table 4. Criterion 1 (Odor) 3: Unpleasant 2: Sensitive but not unpleasant 1: Almost not noticeable 0: Not noticeable at all Criterion 2 (Sensations other than odor (e.g., scratchy throat, itchy or stinging nose)) 3: Unpleasant 2: Sensitive but not unpleasant 1: Almost not noticeable 0: Not noticeable at all Judgment: × (Poor usability): The sum of Criterion 1 and Criterion 2 is 5 or more △ (Issues with usability): The sum of Criterion 1 and Criterion 2 is 3 to 4 ○ (No problems with usability): The sum of Criterion 1 and Criterion 2 is 2 or less

[0063] It was confirmed that the user experience was good when the transpiration rate of natural pyrethrin was between 0.1 mg / hour and 2.0 mg / hour. On the other hand, it was confirmed that the user experience deteriorated when the transpiration rate of natural pyrethrin exceeded 2.0 mg / hour.

[0064] The present invention provides a pest control composition and a pest control method with excellent pest control effects.

[0065] 1. Pest control agent for heat vaporization 2. Heating element 3. Liquid absorption wick 4. Liquid bottle

Claims

1. A pest control composition comprising natural pyrethrin, a radical chain inhibitor, a peroxide decomposer, and a solvent, wherein heating at 140°C causes the natural pyrethrin to evaporate at a rate of 0.1 mg / hour to 2.0 mg / hour for 116 hours.

2. The pest control composition according to claim 1, wherein the radical chain inhibitor comprises at least one phenolic antioxidant selected from the group consisting of dibutylhydroxytoluene and butylhydroxyanisole.

3. The pest control composition according to claim 1, wherein the peroxide decomposing agent comprises a phosphorus-based antioxidant having a phenyl group.

4. The pest control composition according to claim 1, wherein the peroxide decomposing agent comprises at least one phosphorus-based antioxidant selected from the group consisting of triphenyl phosphite, tetraphenyldipropylene glycol diphosphite, diphenyl mono(2-ethylhexyl) phosphite, di-n-decylphenyl phosphite, diphenyl mono(tridecyl) phosphite, and triisodecyl phosphite.

5. The pest control composition according to claim 1, wherein the peroxide decomposing agent contains triphenyl phosphite.

6. The pest control composition according to claim 1, wherein the mass ratio of the radical chain inhibitor to the peroxide decomposer is 1:0.010 to 1:

8.

7. A pest control composition according to any one of claims 1 to 6, which is a pest control preparation for heat vaporization.

8. A heat vaporization type insecticide device comprising a liquid medicine bottle filled with the insecticide composition described in claim 7, a liquid absorption wick, and a heating element.

9. A method for controlling pests, comprising the step of evaporating natural pyrethrin into the air at a evaporation rate of 0.1 mg / hour to 2.0 mg / hour for 116 hours.

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