JPH07100641B2 - Potency enhancer for aqueous insecticides for heat evaporation - Google Patents

Description

Detailed Description of the Invention

[Industrial applications]

The present invention relates to a potency enhancer for an aqueous insecticide for heat vaporization, which is applied to a system in which an insecticide is evaporated by heating at 80 to 200 ° C.

[Prior art]

Heretofore, (1) so-called mosquito coil and (2) electric mosquito mat have been popular as a method for heating and evaporating a drug for the purpose of insecticidal action. However, in recent years, the method of immersing the porous liquid absorbent core in the drug solution and heating the upper part of the core to heat and evaporate the drug does not require replacement of the mat etc. each time, and the effect is stable for a long time. For this reason, various proposals have been made for improving the drug formulation and the material and composition of the absorbent core for this method. For example, in Japanese Examined Patent Publication No. 61-23163,
A drug in which allethrin or an isomer thereof is used as an insecticide and which is dissolved in a hydrocarbon solvent having a specific high boiling point range is disclosed, and JP-A-63-48201 discloses a compound having 12 carbon atoms.
Attempts have been made to incorporate ~ 18 aliphatic hydrocarbons with insecticides and antioxidants which do not substantially evaporate at heating temperatures of 110-140 ° C.

[Problems to be Solved by the Invention]

Although these conventional chemical agents for heating and evaporation have some tentative results in terms of transpiration and usability, they are all oil-based oils, and they are highly flammable and can avoid the danger of fire. It wasn't. Furthermore, in the above-mentioned prior art, there is no specific proposal for enhancing the efficacy of insecticides. In view of the above situation, the present invention eliminates the danger of the conventional heat-evaporating agent against fire, and directly enhances the efficacy of the insecticide, and an object thereof is to provide a potency enhancer of the heat-evaporating aqueous insecticide. And

[Means for Solving the Problems]

As a result of intensive studies conducted by the present inventors in order to solve the above-mentioned problems, it is quite surprising that a specific surfactant uses a certain insecticidal active ingredient (a pyrethroid compound) as an aqueous insecticide. The inventors have completed the present invention, finding that it not only enables it but also enhances the efficacy of the active ingredient. By the way, as an aqueous insecticide containing a pyrethroid, some spray preparations have already been developed, but they have been put into practical use only in Japan. Moreover,
Its active ingredient is limited to phenothrin and permethrin, and the surfactants such as polyoxyethylene polystyryl phenyl ether and alkylbenzene sulfonate, which are mixed in these preparations, are generally non-volatile and 80-200.
None of them evaporated when heated to ℃. From such a situation, it has been generally considered that when an aqueous insecticide is used for heat evaporation, the aqueous insecticide loses its balance and cannot perform its evaporation function. However, the present inventors have paid attention to a low boiling point surfactant,
When a heat transpiration test was carried out by preparing an aqueous insecticide using these, the transpiration of the active ingredient can be constantly connected for a long period without losing the balance of the component composition, particularly in the method using the absorbent core, and It was revealed that a higher insecticidal effect can be obtained. That is, the present invention comprises one or more surfactants that evaporate at a heating temperature of 80 to 200 ° C. The present invention relates to an efficacy enhancer for an aqueous insecticide for heat transpiration containing pyrethroid as an active ingredient. Among the above surfactants, those having a boiling point at 5 mmHg of 250 ° C. or less are preferable. Incidentally, the surfactant in the present specification means one capable of stably maintaining a pyrethroid compound in an emulsified state in water or in a solubilized state regardless of the presence or absence of micelle formation,
In a broad sense, it also includes a solvent that is compatible with water and oil. In general, the solubilized type water-based insecticide is less likely to cause liquid phase separation and the like in comparison with the emulsified type and is superior in usability, and thus is suitable for the heat evaporation insecticide method. As a surfactant suitable for the present invention, the following formula I: R—O (C ₃ H ₆ O) _m · (C ₂ H ₄ O) _n · H (I) (In the formula, R has 1 to 8 carbon atoms. Represents an alkyl group of
And n represent the integer of 0-6. ) A nonionic polyoxyalkylene alkyl ether compound represented by the following formula II: (In the formula, R ′ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and m and n represent an integer of 0 to 6.) A nonionic polyoxyalkylene phenyl ether compound Further, a polyoxyethylene fatty acid ester represented by the following formula III: R—COO— (CH ₂ CH ₂ O) _n · H (III) (wherein R and n have the same meanings as described above), Formula IV or
V: (Wherein R represents the same meaning as described above), a polyhydric alcohol fatty acid partial ester represented by the following formula VI or VII: (In the formula, R ″ is an alkyl group having 1 to 8 carbon atoms or 1
Represents a phenyl group in which one hydrogen atom may be substituted with an alkyl group having 1 to 3 carbon atoms. ) A polyhydric alcohol partial ether represented by the formula (In the formula, 1, m and n represent integers of 0 to 8), polyoxyethylene polyoxypropylene glycol, polyoxyethylene polyhydric alcohol fatty acid partial ester, and alkylolamide of fatty acid are exemplified. However, the present invention is not limited to these. Particularly preferred surfactants are those of the above formulas I and II, in which R represents an alkyl group having 3 to 8 carbon atoms, R'represents a hydrogen atom, and when either m or n is 0, the other is It is an integer of 2 to 5, or both m and n represent an integer of 2 or 3, which have sufficient solubility and are not so high in viscosity. Some of them, such as oxyethylene butyl ether (n = 2), are repellent to mosquitoes and are excellent in usability. In ordinary production, it is obtained as a mixture of compounds having different degrees of polymerization, and m and n are often expressed as an average number of moles, but it goes without saying that both single products and mixtures are included in the present invention. . The amount of the efficacy enhancer of the present invention is 10.0 to 70.0% by weight.
And the balance is mainly a pyrethroid compound and water as shown below. In addition, if necessary, to the extent that these surfactants do not impair the characteristics of the present invention, a small amount of a cationic surfactant,
An anionic surfactant, amphoteric surfactant or organic solvent may be blended. In the present invention, a pyrethroid compound is used as an active ingredient of the aqueous insecticide for heat evaporation from the viewpoint of safety.
It is preferable that 0.3 to 10.0% by weight of these be compounded alone or in combination. For example, the following insecticides can be exemplified, but of course the invention is not limited thereto. a) 3-allyl-2-methylcyclopent-2-ene-
4-on-1-yl d-cis / trans-chrysanthemate (trade name; Pinamine Forte; Sumitomo Chemical Co., Ltd.) b) (S) -2-methyl-4-oxo-3- (2- Propynyl) cyclopent-2-enyl d-cis / trans-chrysanthemate (generic name; Praresulin) c) 5-propargyl-2-furylmethyl d-cis /
Trans-chrysanthemate (trade name; Pinamine D Forte: manufactured by Sumitomo Chemical Co., Ltd.) d) 1-ethynyl-2-methyl-2-pentenyl d-
Cis / trans-chrysanthemate (generic name; empentrin) e) d-3-allyl-2-methylcyclopent-2-en-4-on-1-yl d-trans-chrysanthate (trade name; exulin) F) 5-benzyl-3-furylmethyl d-cis / trans-chrysanthate (trade name; Kryslon Forte: Sumitomo Chemical Co., Ltd.) g) 3-phenoxybenzyl d- Cis / trans-chrysanthate (generic name; phenothrin) h) 3-phenoxybenzyl 2,2-dimethyl-3-
(2,2-Dichlorovinyl) cyclopropanecarboxylate (generic name; permethrin) i) 3-allyl-2-methyl-cyclopent-2-en-4-one-1-yl 2,2,3,3-tetra Methylcyclopropanecarboxylate (generic name; terrareslin) j) 1-ethynyl-2-methyl-2-pentenyl 2,2
-Dimethyl-3- (2,2-dichlorovinyl) cyclopropanecarboxylate k) 3-phenoxybenzyl 2- (4-ethoxyphenyl) -2-methylpropyl ether (generic name; etophane prox) l) dimethyl (4 -Ethoxyphenyl) {3- (3-phenoxy-4-fluorophenyl) propyl} silane m) 2-methyl-2- (4-ethoxyphenyl) -5-
(3-Phenoxy-4-fluorophenyl) pentane Among these, the insecticides a) to d) are preferable in terms of their industrial availability, efficacy, safety and transpiration property, and among them, the insecticide c) is excellent. . Further, in the present invention, the heat-transpiration aqueous insecticide, if necessary organic phosphorus agents, other insecticidal components such as carbamate agents, fungicides, components such as repellents, or stabilizers, synergists, dyes, It is also possible to appropriately add an organic solvent or the like as a fragrance or an auxiliary agent. Aqueous insecticide for heating evaporation containing the efficacy enhancer of the present invention as described above is applied to a system in which the insecticide is evaporated by heating at 80 to 200 ° C., but in particular, a porous liquid absorbent core in the chemical solution. It is suitable for a system in which a part of the core is dipped to absorb the drug solution into the core and the upper part of the core is heated to evaporate the absorbed drug. As the heating method, either direct heating or indirect heating can be applied, but in consideration of the decomposition loss of the drug and the like, indirect heating is preferred. The first specific example applied to this method
Shown in the figure. Aqueous insecticide for heat transpiration containing the efficacy enhancer of the present invention 1
Is poured into a plastic drug solution container 2 having excellent chemical resistance such as polypropylene, PET, polyvinyl chloride, etc., and the liquid absorbent core 3 is held in a hermetically sealed shape via an appropriate holder, and then stored in the heating evaporation device 4. It As a shape of the chemical liquid container 2, a cylindrical shape has been generally used, but for example, a recess is formed in the bottom,
If a groove or streak is provided on the cylindrical surface, or if it has a polygonal shape, it can be easily grasped by hand and can be stored in the evaporation device 4 easily, which is convenient. In addition, the liquid absorbent core 3 is made of an inorganic substance such as calcium carbonate, magnesium, clay, talc, kaolin, diatomaceous earth, gypsum or porcelain substance, or a heat-resistant polymer substance, wood powder, pulp charcoal powder, activated carbon or the like. It is possible to use a powder obtained by firing or hardening it with an appropriate binder, or a material such as felt, non-woven fabric, asbestos, wood, bamboo, etc., which allows liquid to flow through by a capillary phenomenon, etc. And is held in the liquid medicine container 2 in the form of a sealed plug. Since the aqueous insecticide 1 of the present invention uses a surfactant having a relatively low boiling point as a potency enhancer, unlike conventional surfactants, even if it is dipped in a liquid absorbing core and absorbed, It was clarified that the surfactant does not accumulate in the solution, and therefore there is little risk of causing problems such as separation of chemicals and clogging. As a conventional method for storing the liquid medicine container 2 loaded with the liquid absorbent core 3 in the heating evaporation device 4, it is of course possible to mount the liquid medicine container 2 in this shape by providing a screw-on type bottom lid as in the conventional method. Although not available, the method of screwing the screw part engraved on the upper side of the drug solution container 2 into the holder provided inside the device is more preferable because the drug solution container 2 can be firmly fixed to the instrument 4 compared to the former method. . Reference numeral 5 is a heating element installed with a gap around the heat receiving portion of the liquid absorbent core 3, and 6 is a power cord to be connected to the heating element 6, which is an extension cord mounting type or a plug terminal is a device 4 It may be a so-called cordless type that is fixed to the device 4, or a storage chamber for storing the power cord may be separately provided in the instrument 4. 7 is a protective cap placed on the upper part of the heating element, which is preferably attached for safety. A transpiration port 8 is formed in the central part of the
The size and shape of the cap 7 protects the evaporative liquid from excessive protection.
Alternatively, it is optional as long as it is not condensed and attached to the device 4. Further, the heating evaporation device is appropriately provided with a vent hole 9 so that the outside air can communicate from the vent hole 9 through the gap between the heat receiving part of the liquid absorbent core 3 and the heating element 5. The position of the communication port 9 may be either the body or the bottom,
The bottom portion is more preferable in that a chimney-type action and effect that provides a stable evaporation function and a high drug diffusion force can be expected. When the water vaporizing insecticide 1 for heating and transpiration containing the efficacy enhancer of the present invention is applied to the above heating and vaporizing instrument 4 and is used with electricity, the insecticide 1 that has penetrated into the heat receiving portion of the liquid absorbent core 3 is indirectly heated by the heating element 5. It evaporates and exhibits an extremely high control effect against mosquitoes, flies, cockroaches, bed bugs, mites and the like. At this time, the efficacy enhancer (surfactant) is also heated and evaporated together with the insecticide, which assists the attachment and penetration of the insecticide into the insect body, and acts to further enhance the insecticidal effect. Furthermore, since the drug solution containing the efficacy enhancer of the present invention is aqueous, the danger of fire, which is the case with conventional oil-based drug solutions, is eliminated, and the odor and usability are also very excellent.

【Example】

Hereinafter, the present invention will be described based on examples, but the present invention is not limited thereto. 2 and 3 show the results of a gas chromatographic method under which the surfactant as a potency enhancer of the present invention and some pyrethroid compounds as an active ingredient were tested under the following conditions. FIG. 2 shows a constant temperature condition and FIG. 3 shows a temperature rising condition.
C (Pinamine Forte), D (Pinamine Forte),
F (praresulin) is a pyrethroid compound, and A (polyoxyethylene butyl ether, n = 2), B (polyoxyethylene hexyl ether, n = 3), E (polyoxyethylene octyl ether, n = 4) are used in the present invention. It is a suitable surfactant. However, in the case of a commercially available surfactant represented by n as the average number of moles, it is shown at the position of the main peak corresponding to the fraction of the average number of moles. Constant temperature condition [Fig. 2] Detector: Hydrogen flame ionization type detector Separation tube: Glass column with inner diameter of about 3 mm and length of about 1 m filled with Chromosolve W impregnated with SE-30 at 5% packing Separation Tube temperature; constant temperature around 140 ° C As shown in Fig. 2, the vapor pressure was higher when the heat-evaporable pyrethroid pinamine forte (D) was adjusted to hold for about 50 minutes. The retention time of Pinamine D Forte (C) was about 30 minutes, and that of Praresulin (F), which had a slightly lower heat transpiration property than Pinamine Forte (D), was about 60 minutes. When SE-30 is used as the packing material, it is generally said that the order of retention time corresponds to the boiling point (low → high) of the compound, and the boiling point of pinamine forte is about 190 ° C / 5mmH.
It is g. On the other hand, the retention time of the polyoxyethylene butyl ether (n = 2), polyoxyethylene hexyl ether (n = 3), and polyoxyethylene octyl ether (n = 4) used for the aqueous insecticide of the present invention are respectively About 2
Min, approx. 10 min, approx. 50 min.
It was within 80 minutes. Temperature rising conditions [Fig. 3] Detector, separation tube; same as constant temperature conditions Separation tube temperature: 100 ° C (maintained for 10 minutes) 100 to 260 ° C (heating rate of 3 ° C per minute) 260 ° C (maintained for 30 minutes) As shown in FIG. 3, when the holding operation of the pinamine forte (D) was adjusted to about 40 minutes under the temperature rising condition, the holding time of each compound was closer to that of the constant temperature condition of, The retention time of Pinamine D Forte (C) is about 35 minutes,
Praresulin (F) was about 42 minutes. On the other hand, polyoxyethylene butyl ether (n = 2),
The retention times of polyoxyethylene hexyl ether (n = 3) and polyoxyethylene octyl ether (n = 4) are about 5 minutes, about 25 minutes, and about 40 minutes, respectively, and the retention time of the main peak is 60 minutes. It was within the range. That is, the efficacy enhancer used in the aqueous insecticide according to the present invention is a surfactant having a relatively low boiling point, so that it can be evaporated together with the pyrethroid compound, accumulate in the absorbent core, or cause clogging. Clearly there is no fear of causing problems. Test example Inner diameter 20 cm, 43 cm high plastic cylinders are stacked in two layers, and the inner diameter is 20
A cylinder with mc and a height of 20 cm is placed, and a cylinder with the same diameter and a height of 20 cm is placed. This four-tiered cylinder is placed on a disk on a stand. There is a 5 cm circular hole in the center of the disk, and an electric fumigant insecticide equipped with the reagent having the formulation shown in the table below is placed on the circular hole and fumigated. Then, in the upper cylinder,
Release 20 dogs and measure the number of rolls over time. exposure
Collect all test insects after 20 minutes and examine their mortality rate after 24 hours. The test was repeated 3 times in a two-stop system to determine the KT ₅₀ value. The test formulations and results are summarized in the table below. The test results show that Test Examples 1 to 3 of the present invention containing a surfactant as a potency enhancer of the present invention showed higher insecticidal efficacy than Control 1 which did not contain this potency enhancer. There is.

【The invention's effect】

As described in detail above, the potency enhancer of the heat-transpiration aqueous insecticide of the present invention promotes the attachment and penetration of the active ingredient (pyrethroid) into the insect body, and therefore the effect obtained only by the conventional insecticide is effective. Is further enhanced. Moreover,
The efficacy enhancer of the present invention, which is a low-boiling-point surfactant, eliminates the risk of fire vaporization of chemicals for heat evaporation. In addition, the heat-transpiration aqueous insecticide containing the efficacy enhancer of the present invention is also excellent in transpiration property and safety for humans and animals. Therefore, it is combined with the increased insecticidal effect and low flammability, The present invention provides an effective insecticide for heat evaporation.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a specific example of a heating evaporation device suitable for applying the aqueous insecticide according to the present invention. In the figure, 1 ... Aqueous insecticide for heating and evaporation 2 ... Chemical solution container, 3 ... Liquid absorption core 4 ... Heating and evaporation device, 5 ... Heating element 6 ... Power cord, 7 ... Protective cap 8 ... Transpiration port, 9 ... Vent port FIG. 2 and FIG. 3 are graphs showing some gas chromatograms of the potency enhancer (surfactant) and the pyrethroid compound used in the present invention, and FIG. The conditions are shown in FIG. 3 which are temperature rising conditions. In the figure, A: polyoxyethylene butyl ether (n = 2) B: polyoxyethylene hexyl ether (n = 3) C: pinaminef D forte D: pinamine forte E: polyoxyethylene octyl ether (n = 4) F ... Praresulin

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Claims (4)

[Claims] 1. A potency enhancer for an aqueous insecticide for heat evaporation comprising a pyrethroid as an active ingredient, which comprises one or more surfactants which evaporate at a heating temperature of 80 to 200 ° C. 2. The efficacy enhancer according to claim 1, wherein the surfactant has a boiling point of 250 ° C. or less at 5 mmHg. Wherein the surfactant has the following formula _{I: R-O (C 3} H 6 O) m · (C 2 H 4 O) n · H (I) ( wherein, R 1 to carbon atoms 8 represents an alkyl group, and m
And n represent the integer of 0-6. ) One or two of the polyoxyalkylene alkyl ether compounds represented by
The efficacy enhancer according to claim 1 or 2, which is one or more kinds. 4. A surfactant having the following formula II: (In the formula, R ′ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and m and n represent an integer of 0 to 6), or one of the polyoxyalkylene phenyl ether-based compounds or The efficacy enhancer according to claim 1 or 2, which is two or more kinds.