AU708907B2

AU708907B2 - Liquid insecticidal preparation for heat fumigation and method for killing insects by heat fumigation

Info

Publication number: AU708907B2
Application number: AU64444/96A
Authority: AU
Inventors: Yoko Kusumi; Tadahiro Matsunaga
Original assignee: Sumitomo Chemical Co Ltd
Current assignee: Sumitomo Chemical Co Ltd
Priority date: 1995-09-14
Filing date: 1996-09-05
Publication date: 1999-08-12
Anticipated expiration: 2016-09-05
Also published as: MY118334A; ITRM960625A1; KR100523676B1; IT1290148B1; FR2738718B1; ES2142205B1; ES2142205A1; TW383213B; MX9604050A; FR2738718A1; AU6444496A; KR970014564A

Description

BACKGROUND OF THE INVENTION 1) Field of the Invention The present invention relates to a novel liquid insecticidal preparation for heat fumigation and a method for killing insects by heat fumigation.

2) Related Art In the conventional method for fumigating a liquid insecticidal preparation by heating, which comprises dipping a part of a porous absorptive wick into i0 the liquid insecticidal preparation, thereby absorbing the preparation into the wick, and heating a different part of the wick from the part dipped in the preparation, thereby fumigating the absorbed preparation, it is difficult to conduct stable fumigation of the preparation for a long time with a stable insecticidal effect due to *clogging of the absorptive wick, changes in the composition of the preparation in the course of heat fumigation, o. etc., and thus it is desired to develop a liquid insecticidal preparation for heat fumigation capable of stable fumigation with a stable insecticidal effect.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem by adding an isopropyl ester of higher fatty acid or dibutyl phthalate to the liquid 2 insecticidal preparation, thereby preventing clogging of the absorptive wick and enabling stable fumigation of the preparation, while maintaining the stable insecticidal effect for a long time.

According to the first aspect of the present invention, there is provided a liquid insecticidal preparation, which comprises 0.1 to 15% by weight of a pyrethroid compound, 0.3 to 10% by weight of an isopropyl ester of higher fatty acid or dibutyl phthalate, on the basis of total preparation, and (c) saturated hydrocarbon(s) having a boiling point of 1800 to 310 0 C. 0eoc O According to the second aspect of the invention, there is provided a method for killing insects 15 by heat fumigation, which comprises dipping a part of a 00porous absorptive wick into a liquid insecticidal 0000 preparation, thereby absorbing the preparation into the wick, and heating a different part of the wick from the part dipped in the preparation, thereby fumigating the absorbed preparation, wherein a liquid insecticidal 0 preparation comprising 0.1 to 15% by weight of a pyrethroid compound, 0.3 to 10% by weight of an isopropyl ester of higher fatty acid or dibutyl phthalate, on the basis of total preparation, and (c) saturated hydrocarbon(s) having a boiling point of 1800 to 310 0 C is used as the liquid insecticidal preparation.

According to the third aspect of the present invention, there is provided use of an isopropyl ester of 3 higher fatty acid or dibutyl phthalate as an anticlogging agent for an absorptive wick for heat fumigation.

Heat fumigation of the present liquid insecticidal preparation never entails clogging of the absorptive wick, enabling stable fumigation while maintaining a stable insecticidal effect for a long time.

DETAILED DESCRIPTION OF THE INVENTION Pyrethroid compound which may be used in the present invention includes, for example, allethrin, :Of bioallethrin, esbiothrin, prallethrin, furamethrin, empenthrin, resmethrin, phenothrin, permethrin, transfluthrin, terallethrin, silafluophen, ethofenprox, etc.

Isopropyl ester which may be used in the present invention includes, for example, isopropyl esters of fatty acids having usually 12 to 18 carbon atoms, such as isopropyl laurate, isopropyl myristate, isopropyl palmitate, isopropyl stearate, etc.

20 Saturated hydrocarbon(s) having a boiling point of 1800 to 310 0 C which may be used in the present invention can be a single saturated hydrocarbon or a mixture of at least two thereof, which must be in a liquid state in every cases, and include, for example, aliphatic saturated hydrocarbon(s) such as undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, etc., and alicyclic 4 saturated hydrocarbon(s) corresponding to the aliphatic saturated hydrocarbon(s). As the saturated hydrocarbon(s), commercially available aliphatic and alicyclic saturated hydrocarbon(s) can be used, such as No. O Solvent H (trademark of Nippon Oil Co., Ltd., Japan), No. O Solvent M (trademark of Nippon Oil Co., Ltd., Japan), No. O Solvent L (trademark of Nippon Oil Co., Ltd., Japan), Normal Paraffin (trademark of Sanseki- Texaco Chemical Co., Japan), Deotomisole A-i (trademark of Yoshitomi Pharmaceutical Industries Ltd., Japan), IP Solvent 2028 (trademark of Idemitsu Petrochemical Co., Japan), Neothiosol (trademark of Chuo Kasei Japan), Norpar 12 (trademark of Exxon Chemical Co., USA), Norpar 13Norpar 12 (trademark of Exxon Chemical Co., USA), Norpar (trademark of Exxon Chemical Co., USA), Isopar M 1 (trademark of Exxon Chemical Co., USA), Isopar L 1 (trademark of Exxon Chemical Co., USA), Isopar V (trademark of Exxon Chemical Co., USA), Exxsol (trademark of Exxon Chemical Co., USA), Exxsol D110 (trademark of Exxon Chemical Co., USA), Exxsol D130 (trademark of Exxon Chemical Co., USA), etc.

The amount of saturated hydrocarbon(s) having a boiling point of 1800 to 310°C is not particularly limited, but is usually 50 99.6% by weight on the basis of total amount of the present preparation.

The present liquid insecticidal preparation may contain perfumes, stabilizers such as BHT, etc., if necessary.

5 An effective amount of the present liquid insecticidal preparation can be fumigated by dipping a part (for example, a lower part) of a porous absorptive wick into the present liquid insecticidal preparation, thereby absorbing the preparation into the wick, and heating a different part of the wick from the dipped part (for example, an upper part when the dipped part is a lower part).

Porous materials for the absorptive wick which may be used in the present invention includes, for example, inorganic powders such as clay, talc, kaolin, diatomaceous earth, gypsum, pearlite, bentonite, acid clay, glass fibers, asbesto, etc., which are bound and molded with a binding agent such as carboxymethyl 15 cellulose starch, gum arabic, gelatin, polyvinyl alcohol, etc. The absorptive wick may contain a pigment, an antiseptic, etc., if desired.

The absorptive wick can be heated at about 1000 to 160°C by indirect heating with a circular heater such as an electric heater.

The present method for killing insects by heat fumigation is very effective, when applied to a heat fumigation type apparatus for killing insects, as disclosed in JP-B-2-25885, etc.

Insects to be killed by the present method are those killed by a pyrethroid compound contained in the present liquid insecticidal preparation and include, for example, mosquitos, houseflies, etc.

11111111 6 BRIEF DESCRIPTION OF DRAWING Fig. 1 shows an example of an apparatus applicable to the present method for killing insects by heat fumigation; Fig. 2A shows an apparatus used in Example 5; and Fig. 2B shows top view of the metallic ring of Fig. 2A.

PREFERRED EMBODIMENTS OF THE INVENTION The present invention will be described in detail below, referring to Examples.

0:00 10 Example 1 Go.: Prallethrin as component and isopropyl palmitate as component were dissolved into Norpar 13 *"(trademark of saturated hydrocarbons commercially available from Exxon Chemical Co., USA) to make 2.6% by weight and 7.7% by weight, respectively, whereby the present liquid insecticidal preparation was obtained.

The preparation was put into a container having a capacity of 45 ml in a heat fumigation type apparatus for killing insects, the apparatus being provided with an absorptive wick, as shown in Fig. i.

In Fig. 1, numeral 1 is a liquid insecticidal preparation, 2 a circular heater, 3 a porous absorptive wick and 4 a container for the preparation 1, and the lower part of porous absorptive wick 3 is dipped in the preparation 1 to absorb the preparation 1 into the wick 3, and the upper part of the wick 3 is heated by the 7 circular heater 2.

Example 2 Prallethrin as component and dibutyl phthalate as component were dissolved into Norpar 13 (trademark of saturated hydrocarbons commercially available from Exxon Chemical Co., USA) to make 2.6% by weight and 7.7% by weight, respectively, whereby the present liquid insecticidal preparation was obtained.

The preparation was put into a container having a capacity of 45 ml in a heat fumigation type apparatus for killing insects, the apparatus being provided with an absorptive wick, as shown in Fig. 1.

eooo Example 3 Allethrin and isopropyl palmitate were 15 dissolved into Neothiosol (mentioned above) to make by weight and 5.0% by weight, respectively, whereby the present liquid insecticidal preparation was obtained.

Example 4 Transfluthrin and isopropyl stearate were dissolved into Norpar 15 (mentioned above) to make by weight and 1.0% by weight, respectively, whereby the present liquid insecticidal preparation was obtained.

Example An apparatus as shown in Fig. 2A was used.

8 Into two glass pipes 11, 4 cm in diameter and 12 cm high, were each provided 10 mosquito female adults (Culex pipiens pallens). Then, both ends each of the glass pipes 11 were closed with a nylon net. The glass pipes were placed in a cylindrical cover of plastics 12, cm in diameter and 30 cm high, provided at the bottom with a metallic ring 13 integrated with a metallic plate 17, about 5 cm in width, having individual tapered holes 16 for setting the glass pipes 11 while setting the glass pipes 11 to the individual tapered holes 16, respectively. A metallic cylinder 14, 20 cm in diameter and cm high, is provided at the bottom end of the cylindrical cover 12. The heat fumigation type apparatus 15 for o killing insects, obtained in Example 1 or 2, which was 15 heated in advance, was provided at the bottom of the metallic cylinder 14. The upper part of the absorptive wick was indirectly heated to 1200 135 0 C. The number of the mosquito female adults knocked down thereby was counted at different time intervals such as 5 hours, 105 hours, 205 hours, 305 hours and 405 hours after the start of the test and KT 50 values (the time in minutes required for knocking down 50% of the mosquito female adults) were calculated by Probit analysis.

Comparative test was also carried out for a case of using diheptyl phthalate in place of isopropyl palmitate used as component in Example i. Results are shown in Table.

9 Table Component

KT

5 s at time intervals given below hr 105 hr 205 hr 305 hr 405 hr Dibutyl 2.6 2.2 2.3 2.4 phthalate Isopropyl 2.5 2.2 2.3 2.4 palmitate Diheptyl 2.7 2.8 3.1 4.0 3.3 phthalate As is apparent from the foregoing Table, the

*O*

lower insecticidal effect was observed when diheptyl phthalate was used as component in place of dibutyl phthalate and isopropyl palmitate.

5 When a similar test was also carried out for a case of using no such component at all, volatization of the effective component was lowered due to clogging of the absorptive wick about 300 hours after the start of the test, and the insecticidal effect cannot be maintained for a long time.

The present method for killing insects by heat fumigation of the present liquid insecticidal preparation can conduct stable fumigation of the preparation for a long time, while maintaining a stable insecticidal effect.

9A Throughout this specification and the claims, the words "comprise", "comprises" and "comprising" are used in a nonexclusive sense.

0:00 0.0.

.9 10 THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS: 1. A liquid insecticidal preparation for heat fumigation, which comprises 0.1 to 15% by weight of a pyrethroid compound, 0.3 to 10% by weight of isopropyl ester of higher fatty acid or dibutyl phthalate, on the basis of total preparation, and (c) saturated hydrocarbon(s) having a boiling point of 180° to 310 0

C.

2. A liquid insecticidal preparation according to Claim 1, wherein the component is an isopropyl ester of higher fatty acid.

3. A liquid insecticidal preparation according to Claim 1, wherein the component is dibutyl phthalate.

:0 4. A liquid insecticidal preparation according to Claim 2, wherein the component is isopropyl laurate, isopropyl myristate, isopropyl palmitate or isopropyl stearate.

A method for killing insects by heat fumigation, which comprises dipping a part of a porous absorptive wick into a liquid insecticidal preparation, thereby absorbing the preparation into the wick, and heating a different part of the wick from the part dipped in the preparation, thereby fumigating the absorbed preparation, wherein a liquid insecticidal preparation comprising 0.1 to 15% by weight of a pyrethroid compound, 0.3 to 10% by weight of an isopropyl ester of higher fatty acid or dibutyl phthalate, on the basis of total preparation, and saturated hydrocarbon(s)

Claims

6. A method according to Claim 5, wherein the component is an isopropyl ester of higher fatty acid.
7. A method according to Claim 5, wherein the component is dibutyl phthalate.
8. A method according to Claim 6, wherein the component is isopropyl laurate, isopropyl myristate, isopropyl palmitate or isopropyl stearate.
9. Use of an isopropyl ester of higher fatty acid or dibutyl phthalate as anti-clogging agent for an absorptive wick for heat fumigation. 9Se* @O DATED THIS 5TH DAY OF SEPTEMBER 1996 SUMITOMO CHEMICAL COMPANY, LIMITED By its Patent Attorneys: GRIFFITH HACK CO Fellows Institute of Patent Attorneys of Australia S° 0.9. 9 A* ABSTRACT OF THE DISCLOSURE A liquid insecticidal preparation for heat fumigation, which comprises 0.1 to 15% by weight of a pyrethroid compound,(b) 0.3 to 10% by weight of an isopropyl ester of higher fatty acid or dibutyl phthalate, on the basis of total preparation, and (c) saturated hydrocarbon(s) having a boiling point of 1800 to 310°C is stably fumigated without any clogging of a porous absorptive wick with a stable insecticidal effect for a long time, when used by dipping a part of the porous absorptive wick therein, thereby absorbing the preparation into the wick, and heating the different part of the wick from the part dipped in the preparation, thereby fumigating the preparation. eftf O no oo o °r° 5* S S 545