JPH0977607A - Insecticidal method by heat evaporation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably evaporate an insecticidal liquid for a long time and attain a stable insecticidal effect. SOLUTION: This insecticidal method by heat evaporation is consisting of immersing a part of a porous liquid absorbing core 3 into an insecticidal liquid to impregnate the core with the insecticidal liquid and heating the upper part of the core to evaporate the impregnated insecticidal liquid. A liquid obtained by compounding a saturated hydrocarbon having a melting point of 180-310 deg.C with 0.1-15wt.% of a pyrethroid compound and 0.3-10wt.% of an isopropyl ester of a higher fatty acid (e.g. isopropyl palmitate) is used as the insecticidal liquid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-evaporative insecticidal method and a heat-evaporative insecticidal liquid.

[0002]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention An insecticide absorbed by immersing a part of a porous absorbent core in an insecticide, allowing the core to absorb the insecticide, and heating the upper part of the core. In the heat-transpiration insecticidal method of evaporating the liquid, it is difficult to obtain a stable insecticidal effect by performing stable evaporation of the insecticidal liquid for a long time due to clogging of the absorbent core, changes in the insecticidal liquid composition in the heating evaporation process, etc. Therefore, there has been a demand for the development of an insecticidal solution for heat transpiration which enables stable transpiration and has a stable insecticidal effect.

[0003]

Means for Solving the Problems The present invention is to solve the above-mentioned problems, and by adding an isopropyl ester of a higher fatty acid, it is possible to prevent clogging of the absorbent core and to stably evaporate the insecticidal liquid. In addition, it is possible to maintain a stable insecticidal effect for a long time. That is, according to the present invention, a part of the porous liquid absorbent core is immersed in the insecticidal liquid, the insecticidal liquid is absorbed into the core, and the absorbed insecticidal liquid is evaporated by heating the upper part of the core. In the heat-transpiration insecticidal method, 0.1-15% by weight of a pyrethroid compound is contained in a saturated hydrocarbon having a boiling point of 180-310 ° C. as an insecticidal liquid.
And a heat-evaporative insecticidal method using a liquid containing 0.3 to 10% by weight of isopropyl ester of higher fatty acid, and 0.1 to 15% by weight of pyrethroid compound, 0.3 to 10% by weight of isopropyl ester of higher fatty acid, and boiling point of 1
It is intended to provide an insecticidal solution for heat-transpiration insecticide, which is dissolved in a saturated hydrocarbon at 80 to 310 ° C.

[0004]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of the pyrethroid compound used in the present invention include allethrin, bioallethrin, esbiosulin, praretrin, flamethrin, empentrin, resmethrin, phenothrin, permethrin, transfluthrin, terraresulin, silafluofen, etofenprox and the like. To be Also,
Examples of the isopropyl ester of higher fatty acid used in the present invention include isopropyl laurate, isopropyl myristate, isopropyl palmitate, and isopropyl stearate, which are isopropyl esters of fatty acids having 12 to 18 carbon atoms.

The boiling point used in the present invention is 180 to
The saturated hydrocarbon at 310 ° C. may be a single kind or a mixture of two or more kinds. No. 0 solvent H (made by Nippon Oil Co., Ltd.), No. 0 solvent M, made by Nippon Oil Co., Ltd., No. 0 solvent L (made by Nippon Oil Co., Ltd.). ), Normal paraffin (manufactured by Mitsuishi / Texaco Chemical), deotomizole A-1 (manufactured by Yoshitomi Pharmaceutical), IP solvent 2028 (manufactured by Idemitsu Petrochemical), neothiozole (manufactured by Chuo Kasei), norper 12 (manufactured by Exxon Chemical), norper 13 ( Exxon Chemical), Norper 15
(Exxon Chemical), Isopar M (Exxon Chemical), Isopar L (Exxon Chemical), Isopar V
Commercially available products such as (manufactured by Exxon Chemical), Exol D80 (manufactured by Exxon Chemical), Exol D110 (manufactured by Exxon Chemical), and Exol D130 (manufactured by Exxon Chemical) can also be used.

[0006] The heat-evaporative insecticidal method of the present invention can be applied to the heat-evaporative insecticidal apparatus disclosed in, for example, Japanese Patent Publication No. 2-25885, and can exert excellent effects. FIG. 1 shows an example of an apparatus used in the method for heat-evaporative insecticidal method of the present invention, in which a part of a porous absorbent core 3 is immersed in the insecticidal liquid 1, and the insecticidal liquid is absorbed in the core. Then, the upper part of the core can be heated by the heating element 2.

Examples of the porous material which is the material of the absorbent core include inorganic powders such as clay, talc, kaolin, diatomaceous earth, gypsum, perlite, bentonite, acid clay, glass fiber and asbestos, and carboxymethyl cellulose, starch,
A product obtained by binding and molding with a sizing agent such as gum arabic, gelatin, or polyvinyl alcohol is used. In addition, a coloring matter, a preservative, and the like may be appropriately added to the absorbent core.

[0008]

The present invention will be described in more detail below with reference to examples. First, an example of the insecticidal liquid for heat evaporation of the present invention will be shown. Example 1 Praletrin and isopropyl palmitate, respectively
Norper 13 to be 2.6% and 7.7% by weight
The solution was dissolved in (Saturated hydrocarbon manufactured by Exxon Chemical Co., Ltd.) to obtain the insecticidal solution of the present invention, which was placed in a container having a volume of 45 ml, a liquid absorbent core was attached, and the insecticidal apparatus was heated and evaporated as shown in FIG.

Example 2 A female of Culex pipiens 10 was placed in a glass tube having a diameter of 4 cm and a height of 12 cm.
The head is released and both ends of the glass tube are closed with a nylon mesh 2
Book cover made of plastic (diameter 18 cm, height 30 cm)
Put it inside and put a metal tube under the cylindrical cover (diameter 20 cm, height
80cm) and a heating evaporation type insecticidal device as shown in FIG. 1 which is preheated on the bottom of the metal cylinder, and indirectly heats the upper part of the absorbent core to 120 to 135 ° C. The number was counted and the KT ₅₀ value (the time required for 50% of the insects to knock down, the unit was minutes) was calculated by the probit method. Further, a test was conducted for comparison also in the case of adding diheptyl phthalate, which is an aromatic dicarboxylic acid ester, in place of the isopropyl palmitate used in Example 1. The results are shown in Table 1.

[0010]

[Table 1] As seen from the results in the above table, when diheptyl phthalate was added instead of isopropyl palmitate, the insecticidal efficacy was clearly decreased. In addition, the same test was conducted in the case where the ester was not added.
From the time when it exceeded 00 hours, the volatilization of the active ingredient decreased due to the clogging of the core, and the insecticidal effect could not be maintained for a long period of time.

[0011]

According to the method of the present invention, the insecticidal liquid is stably evaporated for a long time to obtain a stable insecticidal effect.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of an apparatus used in the method for killing insects by heat evaporation according to the present invention.

[Explanation of symbols]

Reference numeral 1 is a chemical solution, 2 is a heating element, 3 is an absorbent core, and 4 is a container containing the chemical solution.

Claims (4)

[Claims] 1. A part of a porous liquid absorbent core is immersed in an insecticidal liquid so that the core absorbs the insecticidal liquid and the upper part of the core is heated to evaporate the absorbed insecticidal liquid. In the heat-transpiration insecticidal method, 0.1-15% by weight of a pyrethroid compound is contained in a saturated hydrocarbon having a boiling point of 180-310 ° C. as an insecticidal liquid.
And a solution containing 0.3 to 10% by weight of an isopropyl ester of a higher fatty acid, which is used as a heat-evaporative insecticidal method. 2. The heat-evaporative insecticidal method according to claim 1, wherein the isopropyl ester of higher fatty acid is isopropyl laurate, isopropyl myristate, isopropyl palmitate or isopropyl stearate. 3. Pyrethroid compound 0.1 to 15% by weight, isopropyl ester of higher fatty acid 0.3 to 10% by weight,
An insecticidal liquid for heat evaporation, which is dissolved in a saturated hydrocarbon having a boiling point of 180 to 310 ° C. 4. The insecticidal liquid for heat transpiration according to claim 3, wherein the isopropyl ester of higher fatty acid is isopropyl laurate, isopropyl myristate, isopropyl palmitate or isopropyl stearate.