JPS602284B2 - How to maintain the effectiveness of volatile insecticides - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling the distribution of the insecticidal component of a diluted insecticide and maintaining its efficacy for 8 hours or more.

An insecticide method in which allethrin is impregnated into an impregnated carrier such as a fibrous, porous synthetic resin, or mineral medium, and the rod is heated to a temperature of 120 to 140 qo using an appropriate method such as an electric heater to disperse the insecticidal component. Insect control methods include, for example, Kosho Tsubaki.
This method is known from Japanese Patent No. 800 and No. 41-4477, and has been put to practical use and widely used.

These insecticidal methods are used to protect the user from pests while sleeping, and the average sleeping time of humans, which is 7.
It is practically important to maintain insecticidal efficacy for ~8 hours. However, in these insecticidal methods, although the insecticidal ingredients themselves have strong efficacy, their efficacy is concentrated in the early stage of heating the mortar, and in the latter half the insecticidal efficacy decreases or becomes completely ineffective. There are drawbacks.
This is because the insecticidal component has a high vapor pressure and good scattering properties, so most of it is dispersed in the barrel at the initial stage of heating. Therefore, it is necessary to maintain the insecticidal ingredient in the barrel for a period of 8 to 1 feeding period. Methods to solve these problems include changing the heating temperature of the impregnated plate to a temperature lower than 120°C, or adding some kind of slow-release agent (dispersion inhibitor) to the insecticidal ingredient in the carrier. One possible method is to impregnate it with water.

However, the former method of lowering the temperature reduces the ability of the insecticidal component to uniformly diffuse into the room after volatilization, which is not preferable for the expression of insecticidal efficacy. Therefore, the present inventors investigated various sustained-release agents to eliminate these drawbacks, and as a result, discovered an extremely effective sustained-release agent that freely controls the brightness of the nematode component.
The present invention was completed after confirming that the adjustment was possible. That is, the present invention has a viscosity of 3 to 25 qo.
At least one dimethylpolysiloxane having a viscosity of 100 centistokes or methylphenylpolysiloxane having a viscosity of 10 to 100 centistokes in 2yo, suitable for pyrethroid insecticides such as chrysanthemum acid ester, tetramethyl, trimethylcyclopropane carboxyl ester, etc. This is a method in which the sustained-release agent is added at a suitable ratio and impregnated into the carrier, and by changing the addition ratio of the sustained-release agent, the duration of dispersion can be freely adjusted to a desired time. The insecticide mixed with this controlled-release agent may be impregnated into fibrous materials or porous synthetic resins, and other porous magnetic materials such as bisque, diatoms, clay, etc.
It can also be used by absorption in mineral powder materials such as white carbon, etc.

It is also suitable for insecticidal methods in which it is formulated into a paste or cream and dispersed over a heating element. This sustained release agent contains biveronyl butoxide, octachlorodipropyl ether, N
- Several insect synergists such as octyl-bicycloheptenedicarpoxyimide, beta-butoxy, beta-thiocyanojethyl ether, etc., jetyl-m-toluamide, ethylhexanediol, 2,3,4,5-bis-(△2-butylene) - It can also be used mixed with a repellent such as tetrahydrofurfural.

In addition, the sustained release agent may be added to an insecticide in advance and impregnated into a fiber board, etc., or mixed with an insecticide synergist or repellent and mixed with the insecticide at the time of use. Regardless of the time order or method, it exhibits excellent effects. Next, the present invention will be explained with examples.

Example 1 Insecticidal ingredients include 40 females of 5-propargyl-2-furylmethyl ester (hereinafter referred to as flamethrin) of chrysanthemum acid and 70 females or 140 females of dimethylpolysiloxane or methylphenylpolysiloxane, and further 2,6 -ditertiarybutyl-4-methylphenol (hereinafter referred to as BH
A fiberboard containing components 1 to 8 below, including 40 fibers (referred to as T), is prepared.

The residual rate of flamethrin after heating these fiberboards to 160°C for 4 hours with an electric heater was compared with the residual rate of a fiberboard (type number 9) on which flamethrin and BHT were adsorbed without containing this sustained release agent. . As a result of the above tests, this sustained-release agent is capable of retaining 30% or more of the rodent component even after 4 hours, and the remaining amount can be changed appropriately by using sustained-release agents with different viscosities. It is possible. This residual insecticidal component has a very large effect on the effectiveness of insecticides after 4 hours, and a residual rate of around 40% is desirable.
It is clear that the present sustained-release agent is optimal as a volatilization inhibitor, that is, a sustained-release agent, for insecticidal ingredients. Example 2 In the same manner as in Example 1, fiberboards were prepared in which the insecticidal component was replaced with various pyrethroids, and the residual rate of the insecticidal component was measured after 16 hours.

Here, 2-methyl-5-propargyl-3-furyl methyl ester of daichusic acid is referred to as propartrin, and will be expressed as such hereinafter. This shows that the present sustained release agent is effective in common with commonly used pyrethroid insecticides.

Example 3 For type numbers 3 and 9 of Example 1, 16,000 yen with electric heater
While heating the specimen, we compared and observed the rate of fall and overturn caused by A. edulis over time.

The results are shown in the figure. The above results show that the effect of the one without the sustained release agent (dimethylpolysiloxane) decreases rapidly after 4 hours, whereas the effect of the one containing this sustained release agent is almost the same as at the beginning even after one feeding period. This shows that it has become possible to continue to maintain the effectiveness of the

Claims (1)

[Claims] 1 Pyrethroid insecticides have a viscosity of 3 to 25℃ at 25℃.
A method for maintaining insecticidal efficacy characterized by blending dimethylpolysiloxane with a viscosity of 100 centistokes or methylphenylpolysiloxane with a viscosity of 10 to 100 centistokes at 25°C.