JP2795876B2 - Smoke sterilization method - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for disinfecting pests that inhabit plants by disinfecting pests using superheated steam and fumifying pests that inhabit plants.

[Conventional technology]

Conventionally, pest control substances (hereinafter referred to as pest control substances)
Smoke smoking is a method of mixing or isolating exterminating substances with oxidizing substances and flammable substances, storing them, evaporating the exterminating substances by heat of combustion, dissipating them into the atmosphere, cooling and smoking. Has been done.

However, this method overheats the pesticidal substance in the air, in an oxidizing agent, or in an oxidizing atmosphere such as a combustion gas.
A significant portion of the pesticides are inactivated by oxidative degradation,
Not only are they not used effectively, but there are problems such as the resulting oxidation products damaging humans and animals or plants.

As a method for solving this problem, the present inventors have previously conducted a method in which superheated steam is passed through a combustible substance without being heated in an oxidizing atmosphere, and is then vaporized and released into the atmosphere to form an atomization. (JP-B-43-2227).

[Problems to be solved by the invention]

By the way, the above method is an epoch-making method in that the oxidative decomposition of the exterminating substance is almost completely prevented, but in order to prevent the thermal decomposition of the exterminating substance, the temperature of the superheated steam and the temperature It is necessary to adjust the amount of the pesticidal substance to be entrained individually according to the pesticidal substance to be used, which is troublesome when using this method, such as complicated operation and complicated operation. Has become.

The present inventors have conducted intensive studies to solve the above-mentioned difficulties. As a result, when a thermal decomposition inhibitor composed of nitrocellulose and / or guanidine nitrate is added to the pesticidal substance, thermal decomposition of the pesticidal substance is suppressed and overheating is prevented. It was found that there was little alteration of the extermination substance without changing the entrainment conditions of steam.

The present invention has been made based on the above findings, without changing the entrainment conditions of superheated steam, not only oxidative decomposition of the extermination substance, but also thermal decomposition is suppressed, showing practically excellent efficacy, It is an object of the present invention to provide a method for sterilizing smoke and killing insects.

[Means for solving the problem]

In order to achieve the above object, the method of the present invention provides a method for controlling pesticidal substances by passing superheated steam directly to vaporize and entrain an aerosol product mainly composed of the pesticidal substance and releasing the substance into the atmosphere. In the method of the present invention, a thermal decomposition inhibitor comprising the nitrocellulose and / or guanidine sulfate is added to the extermination substance.

The thermal decomposition inhibitor used in the method of the present invention has a property of being heated in contact with superheated steam and being heated to be decomposed or hydrolyzed and vaporized, and here, either nitrocellulose or guanidine nitrate is used. Or both are used. It is preferable to adjust the amount to be used according to the temperature of the superheated steam or the amount of the accompanying pesticidal substance (vapor pressure of the pesticidal substance).
It is in the range of 0.05 to 10 parts by weight based on parts by weight.

When the above-mentioned thermal decomposition inhibitor is added, the difference in the decomposition rate of the extinguishing substance thermally decomposed by the temperature of the superheated steam is small, so that the operation can be performed with the temperature of the superheated steam being almost constant, so that the handling becomes simple, Various pesticidal substances can be smoked efficiently at the same time, and the desired sterilization and insecticidal action of each pesticidal substance can be performed in a single smoking operation.

Further, according to the method of the present invention, a pesticidal substance having a low vapor pressure is easily vaporized and smoked, and its rate is high. Although the reason is not clear, it is considered that a large amount of gas is generated due to the autolysis, hydrolysis, and the like of the thermal decomposition inhibitor.

Examples and Comparative Examples Next, the methods of the present invention will be described with reference to Examples and Comparative Examples.

Example 1 The upper part of a stainless steel boiler having an inner diameter of 11 cm and a height of 12 cm was connected to one end of a stainless steel heating tube having an inner diameter of 5 mm and a length of 10 cm provided with a nichrome heating wire, and the other end of the heating tube was connected to an inner diameter of 4.2 mm. It was connected to an exterminating substance receiver having a height of 6 cm and was used as a smoker for exterminating substances.

N '-(dichlorofluoromethylthio) -N, N-dimethyl-N'-phenylsulfamide: 3 g of "Eupalene", 3 g of nitrocellulose as a thermal decomposition inhibitor, and a particle size of about 3 g Mix and fill 20 g of 8 mesh vermiculite, put 300 ml of water in a boiler, heat with propane gas, generate steam at a rate of 3.7 g / min, heat with a heating tube, and use a rheostat provided on a nichrome wire. Adjusted to various temperatures, introduced into the above-mentioned exterminating substance receiver, the fumes generated thereby were collected by a condenser equipped with a cooling pipe, and the decomposition rate of upalene at each temperature was measured by gas chromatography. . The results are shown in Table 1.

Comparative Example 1 Except that no thermal decomposition inhibitor (nitrocellulose) was added, the decomposition rate of upalene at various heated steam temperatures was determined in the same manner as in Example 1. The results are shown in Table 2.

Example 2, Comparative Example 2 Ethyl paranitrophenothiobenzenephosphonate as a pesticide; "EPN", 0,0-dimethyl-S-2-ethylthioethyl phosphorodithioate; "ecatin",
6-methylquinoxaline-2,3-dithiocarbonate;
"Molestan", tetrachloroisophthalonitrile:
"Daconyl", N- (3,5 dichlorophenyl) -1,2-
Dimethylcyclopropane-1,2-dicarboximide:
"Sumirex", 1- (4-chlorophenoxy) -3,
3-dimethyl-1- (1,2,4 triazol-1-yl)-
2-butanone; "Bileton" and "Eupalen"
And the decomposition rate of each extermination substance was measured in the same manner as in Example 1 and Comparative Example 1 except that the superheated steam temperature was kept constant at 300 ° C. The results are shown in Table 3.

Example 3 Except that guanidine nitrate (3 g) was used in place of nitrocellulose, various pesticidal substances were smoked in a small horticultural glass room in the same manner as in Example 2, and pests living in the room were smoked. The pest control effect was measured after 12 hours, and the disease control was measured after 1 week.

 The results are shown in Table 4.

Comparative Example 3 Exterminating effect was measured in the same manner as in Example 3 except that guanidine nitrate was not used. The results are shown in Table 5.

[Effects of the Invention] As described above, the method of the present invention significantly suppresses decomposition of a pesticidal substance, improves not only the bactericidal insecticidal effect, but also the decomposition rate even when using superheated steam at the same temperature. Since there is not much change, superheated steam of the same temperature can be used for various extermination substances, so that handling is simplified, and since various destruction substances can be efficiently smoked by superheated steam of the same temperature, This is a method having many advantages such that various pests corresponding to these can be efficiently removed by a single operation.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masakatsu Ikenoya 7-10-1 Ichinomiya, Samukawa-cho, Koza-gun, Kanagawa Prefecture Inside the Sanko Chemical Industry Co., Ltd. Technology Center (72) Inventor Isao Kiwada, Samukawa, Koza-gun, Kanagawa 7-10-1, Machi Ichinomiya, Sanko Chemical Industry Co., Ltd. Technology Center (56) References JP-A-54-44027 (JP, A) JP-A-53-121927 (JP, A) JP-A-2-212403 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) A01N 25/18 A01N 25/22 A61L 2/20

Claims (1)

(57) [Claims] (1) passing superheated steam directly through a pesticidal substance to vaporize and entrain an aerosol product mainly composed of the pesticidal substance;
A method for disinfecting fumes, which is released into the atmosphere and turned into fumes, which comprises adding a thermal decomposition inhibitor consisting of nitrocellulose and / or guanidine nitrate to the extermination substance.