JPH01308204A - Method of insecticide by heating and transpiration - Google Patents

Abstract

PURPOSE:To continue insecticide effect in a long period of time, by dipping liquid-absorbent core on which inorganic powder is stuck with glue into a solution comprising aliphatic hydrocarbon solvent and pyrethroid-based insecticide compound dissolved in said solvent, indirectly heating upper part of said core and transpirating said insecticide solution. CONSTITUTION:A pyrethroid-based insecticide compound (e.g., allethrin, 'Pynamin Forte(R)')is dissolved in 10-18C aliphatic hydrocarbon solvent (preferably n-paraffin, isoparaffin) with a concentration of 3-8wt.%, then said solution is absorbed within an inorganic molded core and upper part of said core is indirectly heated at 60-135 deg.C, thus the insecticide is transpirated and insect- killing is performed. An inorganic molded core composed of mineral powder such as kaolin or activated clay is solely or together with wood powder, etc., solidified with glue, is preferable. By said method, clogging of the liquid- absorbing core is surely avoided and sufficient insecticide effect is exhibited in a long period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat evaporation insecticidal method, specifically, a method for immersing a part of a liquid-absorbing wick in an insecticidal liquid so that the wick absorbs the insecticidal liquid, and also The present invention relates to a heating transpiration insecticidal method in which the upper part is indirectly heated to evaporate the sucked insecticidal liquid. .

Conventional technology and its problems Traditionally, as a method of heating and evaporating chemicals for the purpose of cascading cars, etc., a device such as an electric mosquito repellent is used to heat and evaporate chemicals on porous substrates (solid mats) such as fiberboard. A commonly used method is to heat and evaporate the adsorbed insecticide. However, in this method, the amount of insecticide that can be impregnated into one solid mat is naturally limited, and it is necessary to replace the mat and dispose of the used mat. Moreover, the volatilization rate of the insecticide adsorbed on the mat decreases over time, which is a serious drawback.In addition, the effective volatilization rate of the insecticide adsorbed on the mat is only about 50%; Insecticide residual rate is 10%
However, it is not possible to maintain a stable insecticidal effect over a long period of time, and there are still considerable economic disadvantages.

As a heating evaporation method that can maintain the insecticidal effect over a long period of time, it solves the problem of replacing the mat and the disadvantage that the insecticidal effect disappears within a short period of time when using the solid mat. A method of heating and evaporating insecticide while absorbing it with a liquid-absorbing wick has been considered, and in fact, various insecticide evaporation devices using such a liquid-absorbing wick have been proposed. In these devices, a solvent solution of an insecticide is placed in a suitable container, which is sucked up using a liquid-absorbing wick made of felt, etc., and heated and evaporated from the upper part of the liquid-absorbing wick.

However, when such a two-type heating evaporation device is actually used, the solvent constituting the insecticide liquid quickly evaporates due to the heating of the liquid absorption wick, and the insecticide liquid gradually evaporates inside the wick. It becomes concentrated, turns into a resin, or the core material is smoked, causing clogging and making it impossible for the insecticidal liquid to absorb and evaporate, making it impossible to achieve a long-term, sustained effect. In addition to unavoidable deterioration over time, the effective volatilization rate was low and the residual rate was high. There are many possible causes of the various adverse effects seen in such heating transpiration methods using wicks, including the type of wick and the type of solvent, as well as the type of insecticide, concentration, heating conditions, etc. It was thought that it would be difficult to eliminate the disadvantages mentioned in Section 2.

An object of the present invention is to provide a heat transpiration insecticidal method that eliminates the drawbacks of the conventional heat transpiration insecticide methods. In particular, the present invention provides an improved method that avoids clogging of the liquid absorbent wick, has a long-lasting effect, and can measure the total amount of insecticide volatilization and the effective volatilization rate. The purpose is to provide a method.

Means for Solving the Problems The present invention involves immersing a part of a liquid-absorbing wick in an insecticidal liquid so that the wick absorbs the insecticidal liquid, and indirectly heating the negative part of the wick to absorb the liquid. In the heating transpiration insecticidal method of evaporating an insecticidal liquid, a solution in which a pyrethroid compound as an active ingredient of the insecticide is dissolved in an aliphatic hydrocarbon solvent having a carbon number of 3-10 to 18 is used as the insecticidal liquid; A liquid absorbent core made of inorganic powder bound with a glue is used as the liquid core, and the upper part of the core is heated to about 60°C to about 135°C.
The present invention relates to a heat transpiration insecticidal method characterized by indirect heating to a temperature of .

According to the method of the present invention, the liquid absorption wick does not become clogged and its lifespan can be extended, and based on this, the evaporability (volatilization amount and effective volatilization rate) of the insecticide can be significantly improved by -1. - It is possible to maintain an excellent insecticidal effect over a long period of time.

In the present invention, the insecticide includes various PI nothroid insecticides conventionally used for pest control.

Specific examples thereof include the following.

03-allyl-2-methylcyclopent-2-ene-4
-on-1-yl dQ-cis/trans-chrysanthemer-1 (generic name allethrin; trade name pinamine; manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as AA) 03-allyl-2-methylcyclopent-2-ene -4
-on-1-yl d-cis/trans-crisantemate (trade name: Pinamine Forte: manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as AB) Od-: 3-allyl-2-methylcyclopent-2-ene- 4-on-1-yl d-trans-chrysanthemate (trade name: Exlin: manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as AC) 03-allyl-2-methylcyclopent-2-ene-4
-on-1-yl d-transucrysanthemate (
-Ship name: Pioarethrin (hereinafter referred to as AD) ON-(3,4,5,6-titrahydrophthalimide)-
Methyl dQ-cis/trans-chrysanthemer 1-
(-Ship name Phthalthrin: Trade name Neopinamine: Manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as AE) ○2-Methyl-4-oxo-3-(2-propynyl)cyclobent-2-enyl chrysanthemate 0 (S)-2- 05-Benzyl-3- Furylmethyl d-cis/trans-chrysantemate (-Ship name: Resmethrin: Product name: Lithronforte: Manufactured by Sumitomo Chemical Co., Ltd., hereinafter AF
05-(2-propargyl)-3-furylmethylchrysanthemate (-Ship name: Furamethrin, hereinafter referred to as AG) 03-phenoxybenzyl 2,2-dimethyl-3-(
2',2'-dichloro)vinylcyclopropane carboxylate (-ship name Permethrin; trade name Exmin: manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as AH) 03-phenoxybenzyl d-cis/trans-crisantemate (-ship Fetuthrin: Trade name Sumitrin: Manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as AI) Oα-cyanophenoxybenzyl isopropyl-4-
Chlorophenyl acetate (-Ship name Fuenvalerate;
Product name Sumicidin: Manufactured by Sumitomo Chemical Co., Ltd., hereinafter A
0(S)-α-cyano-3-phenoxybenzyl (IR
, cis) -3-(2,2-dichlorovinyl)-2,2
-dimethylcyclopropanecarboxylate (hereinafter AL
) 0 (R,S)-α-cyano-3-phenoxybenzyl (IR,l5)-cis/trans-3-(2,2-dichlorovinyl)-2,2-dimethyl, cyclopropanecarboxylate ( Oα-cyano-3-phenoxybenzyl d-cis/trans-chrysanthemate (hereinafter referred to as AN) 01-ethynyl-2-methyl-2-pentenyl cis/trans-chrysanthemate (hereinafter referred to as AO) 01 -ethynyl-2-methyl-2-pentenyl2.2-
Dimethyl-3-(2-methyl-1-propenyl)cyclopropane-1-carboxylate (hereinafter referred to as AP) 01-ethynyl-2-methyl-2-pentenyl 2.2,
3.3-Tetramethylcycloprobanca, lupoxylate (hereinafter referred to as AQ) 01-ethynyl-2-methyl-2
-Pentenyl 2,2-dimethyl-3-(2,2-dichlorovinyl)cyclopropyne-1-carboxylate (hereinafter referred to as AR) 〇3-aryl-2-methylcyclopent-2-ene-4
-on-1-yl 2,2,3.3-tetramethylcyclopropanecarboxylate (-ship name telarethrin) The above insecticides include commonly used efficacy enhancers, volatilization rate improvers, deodorants, Various additives such as fragrances can be optionally added. Efficacy enhancers include piperonyl butoxide, N-probylisome, MGK-264, cinepirin 222, cinepirin 500, Riesen 38
4.IBTA.

S-421, etc., volatilization rate improvers include phenethyl isothiocyanate, dimethyl pymixate, etc., deodorants include lauric acid methacrylate (LMA), and fragrances include citral, citronellal, etc.

The above insecticides are prepared in solution form. As the solvent for preparing the insecticide solution, various organic solvents, typically hydrocarbon solvents, can be used, but in particular aliphatic hydrocarbons (paraffinic solvents) with a boiling point range of 150 to 350°C (hydrocarbons and unsaturated aliphatic hydrocarbons) are preferred, and low paraffins having the boiling point range mentioned above contain 1-0 to 18 carbon atoms.
Dictionary of O
rganic compounds.

5th CD, 1982]. Among these, especially n
-Paraffin, isoparaffin, etc. are suitable for practical use because they are non-toxic, have no odor, and have very little risk of fire.

The solvent solution of the above insecticide is appropriately determined depending on the type of pyrethroid insecticide to be used and is not particularly limited, but the insecticide concentration is usually about 1 to 10% by weight, preferably 3 to 8% by weight. It is best to prepare it so that

In the present invention, an inorganic molded core made by caking inorganic powder with a sizing agent is used as the liquid-absorbing core. Specific examples include porous porcelain, glass fiber, inorganic fibers such as asbestos hardened with gypsum or bentonite, kaolin, activated clay, talc, diatomite, clay, perlite, gypsum, bentonite tanium, and glassy volcanic rock. Mineral powders such as calcined powder, glassy volcanic ash calcined powder, etc. alone or together with wood flour, rehydrated powder, activated carbon, etc., and examples include those hardened with dextrin, starch, gum arabic, synthetic glue CMC, etc. can.

A particularly preferred liquid-absorbing core is the above-mentioned mineral powder alone, or a mixture of 1-00 parts by weight of the mineral powder and wood flour, or 10-300 parts by weight of the wood flour mixed with back powder and/or activated carbon up to an equal weight. A sizing agent is added to the mixture to make up 5 to 25% by weight of the total weight of the liquid-absorbing core, water is added thereto, the mixture is kneaded, and then extrusion molded and dried. The liquid absorption rate of the liquid absorption core is preferably 1 to 40 hours, preferably 8 to 21 hours. This liquid absorption rate is measured by dipping a liquid absorption wick with a diameter of 7 mm and a length of 70 mm into an n-paraffin liquid at a temperature of 25°C to a depth of 15 mm from the bottom, and measuring the time it takes for the n-paraffin to reach the love love. means the value determined by In addition, in addition to mineral powder, wood flour, and sizing agent, the above-mentioned liquid-absorbing core contains pigments such as macarite green, sorbic acid and its salts, mold inhibitors such as dehydroacetic acid, etc. as necessary. You can also.

As an apparatus suitable for carrying out the method of the present invention, any of various conventionally known suction type heating evaporation apparatuses can be used. Examples include, for example, Japanese Patent Publication No. 52-Cho 21-06,
Examples include those described in Japanese Utility Model Application Publication No. 58-4567'0, and specific examples thereof are shown in the attached drawings.

FIG. 1 is a schematic diagram of a suction heat evaporation device suitable for carrying out the method of the present invention, which comprises an insecticide solution having a wick support (2) supporting a wick (1). A storage container (3) and a liquid absorbent wick inserted into the container with its upper part protruding.
1), a hollow disk-shaped heating element (4) for indirectly heating its two side surfaces, a support part (5) for supporting the heating element (4), and support legs (6). A heating element support stand (
7), and the heating element (4) has a cord (not shown) for energizing it to generate heat.

In addition, the heating element used in the above-mentioned device is generally a heating element that generates heat when energized, but is not limited to this (for example, a heating element that uses an air oxidation heating material, a platinum catalyst, etc.) is used. Any known heating element such as a heating material may be used.

According to the method of the present invention, the desired insecticidal effect is achieved by heating the liquid absorbent core to an appropriate temperature at which the insecticidal liquid composition can evaporate from the liquid absorbent core. The heating temperature is determined appropriately depending on the type of insecticide, etc., and is not particularly limited, but is usually about 70 to 50°C, preferably 135 to 145°C.
The surface temperature of the heating element is within the range of about 60°C to about 1-35°C, preferably about 120-13°C.
Corresponds to 0°C.

Thus, according to the present invention, it is possible to reliably avoid clogging of the liquid-absorbing wick and volatilize the insecticide for a long period of time at an insecticide concentration that provides a sufficient insecticidal effect.

Example Examples will be given below to explain the present invention in more detail.

Example 1 20 parts by weight of starch and water were added to 60 parts by weight of perlite and 20 parts by weight of wood flour, and after kneading, extrusion molding and drying were carried out to form a porous liquid-absorbing core (diameter 7!■ x length 70 mm, oil-absorbing core). 14 hours) was prepared.

Furthermore, insecticidal liquid compositions (Nos. 1 to 13) were obtained using each of the insecticides and organic solvents shown in Table 1 below at predetermined ratios. - Table 1 The symbols in the solvent section of Table 1 indicate the following.

B B...Boiling point 180-210℃/760mmHg
Aliphatic hydrocarbon B C...boiling point 210-240°C/760mmHg
Aliphatic hydrocarbon B D ...boiling point 240-270°C/7.60mmH
g of aliphatic hydrocarbon B E ...boiling point 270-300°C/760mmH
50 g of each of the insecticidal liquid compositions prepared above were placed in the container (3) shown in FIG. A sample of the composition was heated to a temperature of 135°C, and a transpiration test of the insecticide in the composition sample by heating was conducted.

In addition, the heating element (4) has an inner diameter of 10 mm and a thickness of 10 m.
A hollow disc-shaped heating element of m was used. In addition, the amount of pesticide volatilization is determined by suctioning and collecting the volatilized vapor into a silica gel column every hour.
This silica gel was extracted with chloroform, concentrated, and then quantitatively analyzed using a gas chromatograph (=16-).

Table 2 below shows the results of the insecticide volatilization amount B/hr per hour 10 hours, 100 hours, 200 hours, and 300 hours after the start of heating the insecticidal liquid composition sample.

Table 2 Table 2 (Continued) From Table 2 above, it is clear that according to the present invention, the improved amount of pesticide volatilization can be sustained over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an example of an apparatus suitable for implementing the method of the present invention, in which (1) is a liquid absorbing wick, (3) is an insecticidal liquid composition storage container, and (4) is a heating element. Show each. (That's all) Figure 1

Claims (1)

[Claims] (1) A heating transpiration insecticidal method in which a part of a liquid-absorbing wick is immersed in an insecticidal liquid to cause the wick to absorb the insecticidal liquid, and the upper part of the wick is indirectly heated to evaporate the sucked insecticidal liquid. In this method, a solution in which a pyrethroid compound as an active ingredient of the insecticide is dissolved in an aliphatic hydrocarbon solvent having 10 to 18 carbon atoms is used as the insecticidal liquid, and an inorganic powder is caked with a glue as the liquid absorbent core. Using a liquid-absorbing wick, the upper part of the wick is approximately 60 mm
A heating transpiration insecticidal method characterized by indirectly heating to a temperature of 135°C to about 135°C.