JPS63130502A - Insecticidal mat - Google Patents

Abstract

PURPOSE:To obtain an insecticidal mat having excellent preservation quality and thermal stability, by including a volatile insecticidal ingredient in cyclodextrin and placing the resultant clathrate material on a mat. CONSTITUTION:An insecticidal mat obtained by including a volatile insecticidal ingredient, particularly preferably pyrethroid based insecticide in cyclodextrin, particularly preferably beta-type and placing the resultant clathrate material on a mat. Oxidation of the volatile insecticidal ingredient can be prevented and stability to light is improved by including the volatile insecticidal ingredient. The volatility thereof by heating is as good as that of the nonclathrate compound. That is, since the volatile insecticidal ingredient is stably present even in preservation of the insecticidal mat as well as in use while heating and moderately volatilized in use while heating, excellent insecticidal effects are sustained for a long period. There is no fear of toxicity without requiring use of noxious oxidizing agents.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an insecticidal mat, and particularly to an insecticidal mat in which volatile insecticidal components contained therein have excellent storage stability and thermal stability. So.

[Prior Art/Problems to be Solved by the Invention] Conventionally, heating type insecticidal mats such as electric mosquito repellent mats have mainly been made of cardboard containing volatile insecticidal ingredients such as pyrethroids.

However, in such insecticidal mats, the volatile insecticidal components are often oxidized and decomposed during heating or storage, resulting in insufficient effectiveness.

Furthermore, in order to prevent this oxidative decomposition, a large amount of antioxidants such as BHA and BIT have been contained. For this reason, the concentration of vaporized BHA and BIT in the air is several hundred 1) I
) M, and there are also reports that often call for consideration of chronic and acute toxicity (safety) to the human body, and social measures are also becoming required.

Therefore, it is an object of the present invention to provide an insecticidal mat whose volatile insecticidal components are stable even during heating and storage.

[Means for solving problems]

The present inventors have continued various studies to achieve this objective, and have found that by including volatile insecticidal ingredients in cyclodextrin, oxidation of the volatile insecticidal ingredients can be prevented and that the volatile insecticidal ingredients can be stabilized against light. Furthermore, we discovered that its volatility upon heating is as good as that of non-clathrate compounds, and that stable and excellent insecticidal properties can be obtained without the need for antioxidants such as BHA and BIT. After further research, the present invention was completed.

That is, the present invention is an insecticidal mat in which a volatile insecticidal component (hereinafter also referred to as an clathrate compound) encapsulated in cyclodextrin is arranged on the mat.

The volatile insecticidal component used in the present invention has the ability to volatilize (
There are no particular limitations as long as the compound exhibits insecticidal activity by volatilizing under heating at about 180° C. and can be included in cyclodextrin. Pyrethroids are generally used as volatile insecticidal ingredients, and they may be either synthetic or natural. Synthetic pyrethroids include allethrin, fresrin, pyrethrin, permethrin, etc.; natural pyrethroids include components of pyrethrum, such as pyrethrin 1)
Examples include pyrethrin (■), cinerin (■), and cinerin (■).

As the mat used in the insecticidal mat of the present invention, it is sufficient to use one conventionally used in this field, which can contain volatile insecticidal ingredients and is heat resistant to heating of about 180 degrees Celsius. The one with the following is used. Specific examples of such materials include cardboard, felt, plasterboard, asbestos paper, and wood chips. There is no particular limit to the thickness of the mat, but from the viewpoint of maintaining appropriate volatility, a thickness of about 0.1 to 3 mm is preferably used.

The cyclodextrin used in the present invention includes α
, β, and γ types, but β type is particularly preferred.

Inclusion of volatile insecticidal components into cyclodextrin is conveniently carried out by means known per se, for example, as follows.

That is, does the cyclodextrin aqueous solution contain volatile insecticidal components? An example of such a method is to gradually add a solution dissolved in an 8 medium (for example, ethanol, etc.) to precipitate the clathrate and filter it out.

In this case, it is desirable to have a chelating agent such as ethylenediaminetetraacetic acid present.

Ma is a mode of disposing the clathrate compound on the mat.

This includes not only the embodiment in which the clathrate compound penetrates into the interior of the mat, but also the embodiment in which the clathrate compound penetrates into the interior of the mat, but it also includes the embodiment in which the clathrate compound penetrates into the interior of the mat. things are used. A specific method is to disperse the clathrate compound in a solvent (for example, polyvinyl alcohol, a mixed solvent of 1 part ethanol, 3 parts glycerin, and 60 parts water) and apply it directly to the mat, or apply it directly to the mat and then dry it. Ru.

There is no particular limit to the amount of the clathrate compound of the present invention disposed in the mat, but it is usually 10 to 50 μ/clI! That's about it.

The insecticidal mat of the present invention is used, for example, by placing it in a so-called electric mosquito repellent or the like and heating it to about 90 to 180°C. In this way, the volatile insecticidal components are volatilized and good insecticidal activity is exhibited.

[Action/Effect]

In the insecticidal mat of the present invention, since the volatile insecticidal component is included in cyclodextrin, the volatile insecticidal component can stably exist not only during storage of the insecticidal mat but also when heated. Because it evaporates in a moderate amount, its excellent insecticidal effect lasts for a long time. Also, BHA and B I
Since there is no need to use harmful antioxidants such as T, there is no concern about chronic or acute toxicity caused by these.

[Example/Experiment example]

Example 1 1 g of pyrethrin and 0.01 g of ethylenediaminetetraacetic acid were dispersed in 10 ml of ethanol, and this was gradually added to 50 ml of a 10% β-cyclodextrin aqueous solution, and the precipitate was collected by filtration and dried.

1 ml of a 20% polyvinyl alcohol solution containing 300 μm of the obtained clathrate compound was applied onto the surface of cardboard with a thickness of 1) and an area of 1° ci, and dried at 40° C. to obtain an insecticidal mat.

Example 2 An insecticidal mat was obtained in the same manner as in Example 1, except that 1 g of Freswan was used instead of 1 g of pyrethrin.

Comparative Example 1 1 g of pyrethrin and 90.01 g of ethylenediaminetetravinegar i
Prepare a mixture of 20% polyvinyl alcohol containing 100μ of 1) 1m+ of the mixture with a thickness of l mu and an area of 10cd.
It was applied onto the surface of cardboard and dried at 40°C to obtain an insecticidal mat.

Comparative Example 2 An insecticidal mat was obtained in the same manner as in Comparative Example 1 except that 1 g of Fresrin was used instead of 1 g of pyrethrin.

Experimental Example 1 (Sustainability Test) The insecticidal mats prepared in Example 1.2 and Comparative Example 1.2 were placed on a hot plate heated to 150°C, and the volatile insecticidal components in the insecticidal mats were heated for a predetermined period of time. The remaining amount was measured. The measurement method was to dissolve the remaining volatile insecticidal components in ethanol 101 after a predetermined period of time, and perform quantitative analysis using reversed phase liquid chromatography. The calculations are shown in Table 1, assuming that the amount of volatile insecticidal components in the insecticidal mat before heating is 100%.

(Margins below) Table 1 Experimental Example 2 (Heat decomposition resistance test) The insecticidal mats prepared in Example 1.2 and Comparative Example 1.2 were cut into pieces, placed in a shield tube with a volume of 200 m1, and sealed. This shield tube is 18
The insecticidal mat was placed in an oven heated to 0°C, and after heating for a predetermined period of time, the remaining amount of volatile insecticidal components in the insecticidal mat was measured. The measurement method was to dissolve the remaining volatile insecticidal components in 10 ml of ethanol after a predetermined period of time, and perform quantitative analysis using reversed phase liquid chromatography. The calculations are shown in Table 2, assuming that the amount of volatile insecticidal components in the insecticidal mat before heating is 100%.

Table 2 Experimental Example 3 (Storage Test) The insecticidal mats prepared in Example 1.2 and Comparative Example L2 were coated with a 40μ polyester/polyethylene laminate film.
I heat sealed it with a thick one.

Heat seal size: 5cm x 4.5cm, inner circumference: 4.
It is 50 x 3 cm. After this heat seal was stored for 3 months at 40° C. and 90% humidity, the remaining amount of volatile insecticidal components in the insecticidal mat was measured. The measurement method is to dissolve the remaining volatile insecticidal components in ethanol 10+wl after storage,
Quantitative analysis was performed using reverse phase liquid chromatography. Note that calculations were made assuming that the amount of volatile insecticidal components in the insecticidal mat before storage was 100%, and the results are shown in Table 3.

Table 3

Claims (3)

[Claims] (1) An insecticidal mat in which a volatile insecticidal ingredient encapsulated in cyclodextrin is arranged on the mat. (2) The insecticidal mat according to claim (1), wherein the volatile insecticidal component is a pyrethroid insecticide. (3) The insecticidal mat according to claim (1), wherein the cyclodextrin is β type.