AU679966B2 - Granular pesticide compositions - Google Patents

Description

AUSTRALIA

Patents Act COMPLETE SPECIFICATION

(ORIGINAL)

Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority Related Art: 0 0 *000 *0 0 *000 Name of Applicant: Zeneca Limited .044

SO

*4 Actual Inventor(s): Kang-Chi Lin Horst Redmer Ernest N. Villafranca Address for Service: 0* *0 *0 PHILLIPS ORMONDE FITZPATRICK Patent and Trade Mhrk Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Invention Title: GRANULAR PESTICIDE COMPOSITIONS Our Ref 366871 POF Code: 205202/192132 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): -1- PR-8707A GRANULAR PESTICIDE COMPOSITIONS Background and Prior Art This invention pertains to granular compositions containing pesticides. More particularly, it relates to granular compositions containing insecticides, particularly S. soil insecticides, and more specifically, pyrethroids, which So have been found to posses both good stability and low mammalian toxicity, while still retaining good bioactivity.

o. The pyrethroids are a well-known class of insecticides and include such commonly employed compounds as permethrin, cypermethrin, allethrin, deltamethrin, resmethrin, and cyhalothrin. Most of the pyrethroids are employed as S wettable powders or liquid compositions for foliar or aerosol spraying. One pyrethroid which has been found to have suitable activity for use as a soil insecticide is tefluthrin, which has thp chemical name 2,3,5,6-tetrafluoro-4-methylphenylmethyl-(la,3a)-(Z)- (±)-3-(2-chloro-3,3,3-trifluoro-l-propenyl)- 2,2-dimethylcyclopropanecarboxylate. For use in soil, tefluthrin has been formulated in granular compositions employing gypsum as the carrier. However, such compositions have been subject to lumping or caking during storage (from water retained in the gypsum during processing) and have also raised problems with agricultural equipment when the relatively hard gypsum particles entered gears and other components, causing damage.

It would be desirable to provide a granular composition, particularly for application to the soil, containing a pyrethroid or other soil insecticide or pesticide, supported

~I

2 on a carrier, which does not produce the lumping, caking or equipment damage caused by gypsum particles.

Additionally, the preparation of the gypsum-supported compositions required that the pesticide first be prepared as an emulsion, which was then used to prepare the final composition. It would also be desirable to obtain a granular pesticide formulation which could be obtained by the more simple technique (commonly used) of spraying a solution of the pesticide on the granules.

C.

Summary of the Invention In brief, this invention comprises a granular pesticidal composition comprising from about 0.1 to about weight percent of a pesticide, from about 1 to about 30 weight percent of a C 1

-C

4 alkyl ester of a fatty acid having from 8 to 18 carbon atoms, or a mixture of such esters, the remainder comprising a granular support.

Detailed Description of the Invention According to the invention pesticidal granular compositions are prepared which contain a pesticide supported on a granular support, preferably a clay support and which also contain from about I to about 30 weight percent of a

C

1

-C

4 alkyl ester of a C 8

-C

18 fatty acid, or a mixture of such esters.

For purposes of convenience, the inventi~o e described below with respect to the pyrethrold insecticide tefluthrin. However, the compositons and method of preparing them, according to-thi4r invention, may be used with a number r--of oth r-p-esticides. In general, the compositions may contain b n "6 "2" l-HI!^ L I -2A- Throughout the description and claims of this specification, the word "comprise" and variations of the word, such as "comprising" and "comprises", is not intended to exclude other additives, components, integers or steps.

For purposes of convenience, the invention will be described below with respect to the pyrethroid insecticide tefluthrin. However, the compositions and method of preparing them, according to this invention, may be used with a number of other pesticides. In general, the compositions may contain

S

S

see *o* l *o *o *ee *o

-W-

3 an insecticide, and more particularly, a soil insecticide, which may be a pyrethroid, a carbamate, an organophosphorus insecticide, or other type of insecticide which is incorporated into the soil. Of these classes, pyrethroids are preferred.

Various materials may be used as the granular support of the compositions of this invention. The preferred materials are clays such as montmorillonite, attapulgite, mica, kaolin, talc, pyrophyllite, vermiculite and synthetic calcium silicates. However, non-clay granular materials such as diatomaceous earth, corn cob, peanut hulls, wood pulp and various cellulosic materials and mixtures of clay and non-clay granular materials such as clay/wood pulp are also suitable for use in these compositions.

The third component required for these compositions is a C -C 4 alkyl ester of a C 8 18 saturated or unsaturated fatty acid or a mixture of such esters. Preferred esters are methyl esters of such acids and more preferred are methyl oleate and the methyl ester of rapeseed oil fatty acid.

Commercial formulations of such esters include Emery 2219 (58% methyl oleate, 24% methyl stearate, 14% methyl linoleate, 4% methyl palmitate), Emerest 2301 (76% methyl oleate, 24% methyl esters of other C 14

-C

18 fatty acids), Emery 2270 (70% methyl laurate, 28% methyl myristate, 1% methyl palmitate), and Emery 2209 (55% methyl caprylate, 40% methyl caprate, 3% methyl caproate, 2% methyl laurate) all available from Henkel Corporation, Emery Group; Stepan C-25 (methyl caprylate methyl caprate), available from Stepan Company; KE-1870 (methyl oleate) and CE-910 (methyl caprylate methyl caprate), available from Proctor Gamble Company, Priolube 1400 (methyl oleate), available from Unichema; PAMAK W4 (tall oil fatty acids), available from Hercules Inc.; ACTINOL FA1 and D30LR (tall oil fatty acids), available from Arizona Chemical Company; Kemester EX-1550 (methyl ester of poly- 4 overized tall oil), Kemester 3695 (methyl ester of dimer acid), and Witconoi 2301 methyl oleate, all available from Witco Corporation; and Edenor ME-SU and Edenor ME-SU/DS-20 (methyl ester of rapeseed oil fatty acid, also known as methyl canolate) available from Henkel AG.

The compositions of this invention are prepared by the very simple method of combining the pesticide with the alkyl ester or esters and spraying the resulting material on the granular support This inve-dion includes compositions in which the content (by weight percent) o alkyl ester or esters is greater than that of the pesticide, as well as those in which the quantity of pesticide is greater than that of the alkyl ester or esters. In the former case, the pesticide may be dissolved in the ester(s); in the latter case a mixture will be formed.

a Compositions of this invention contain from about 0.1 to about 30 weight percent, 15 preferably from about 0.5 to about 25 weight percent, and most preferably from about 1 to about 15 weight percent, of a pesticide, from about 1 to about weight percent, preferably from about 6 to about 21 weight percent, and most preferably from about 6 to about 18 weight percent, of the C 1

-C

4 alkyl ester of a fatty acid, or mixture of such esters, the remainder comprising the support, Other 20 ingredients, such as stabilizers (for instance polyalkylene glycols such as dipropylene glycol) and/or antioxidants may also be included in the composition if desired. Suitable antioxidants include propyl gallate, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), tall oil rosin, tertiary butyl hydroquinone and natural tocopherols (Vitamin E).

The compositions may also include certain additional solvents such as paraffinic, isoparaffinic or naphthenic solvents such as Vista LPA-170 or Vista LPA-210, available from Vista Chemical Co., Houston, Texas.

M

5 General Procedure The compositions of the following examples are prepared by the following general procedure: The indicated amount of tefluthrin (technical grade; 96.2% purity except as indicated) was added to the indicated amount of the fatty acid ester to form a solution. That solution was then sprayed or aspirated onto the i.dicated amount of support in a mixer to produce the supported granular composition.

The following examples show the amounts of technical grade tefluthrin, fatty acid ester and support in both absolute and percentage by weight of the overall composition.

S Example 1 Ingredient Amount Weiht Tefluthrin 12.66 1.62 Emerest 2301* 78.14 10.00 montmorillonite c" lay 662.83 88.38 *contains 76% by weight methyl oleate and 24% by weight methyl esters of other C14-C18 acids.

Example 2 Ingredient Amount eight% tefluthrin 12.20 1.62 Emerest 2301 75.29 10.00 dipropylene glycol 7.52 1.00 montmorillonite clay 655.35 87.38

-M

-6 Incaredient tefluthrin Emerest 2219* mont-morillonite clay Example 3 Amountg.) 22 .68 70.00 607. 32 Weicrht% 3.24 10.00 86.76 *contains 58% by weight methyl oleate, 24% methyl stearate, 14% methyl linoleate and 4% methyl palmitate.

Example 4 ingredient Aon g1Weictht!% tefluthrin 11.34 1.62 EDENOR ME 42.0 6.00 inontmorillonite clay 92.38 *Methyl ester of rapeseed oil fatty acid containing 90.5% methyl, esters of C 18 fatty acids.

In redient tefluthrin Witconol 2301 montmorillonate clay Example Amou~J~j.

5.12 7.38 We ichtA 1.64 2.36 300.00960 96.00

IG

-7 Ingiredient tefluthrin Emerest 2301 mica Example 6 Amount 8 .10 50.00 441.90 Weig~ht% 1.62 10.00 88.38 Example 7 fi' In erdient tefluthrin (95% pur'ity) Witconol 2301 propylene glycol Biodac 1240 (cellulosic wood pulp) Weigiht% 63 .2 400.*0 40.0 3496.8 1.58 100.00 1.00 87 .42 *0 Example 8 0 *0 Ingredient Amut(.

tefluthrin (9s% purity) 2.40 V 4icconol 2301 15.13.

propylene glycol 1.58 attapulgite clay 132.03 1.59 10.00 1.05 87.36 Weight%

I

-8a- EXamv1eg 9 Incrredient Amount tefluthrin purity) 2.40 Witconol 2301 15.11 propylene glycol 1.58 diatomaceous silica 132.03 K e j ht 1.59 104 1 87.36 got* 0.

Example ingrredient tefluthrin* Emerest 2306 U** montmorillonite, clay 9%prt 1.63 8.00 90.37 0055 5045

S..

0050

S.

5* 5 S S

S.

*Emerest 2301 plus 0.5% BHT stabilizer Exaple11 Ingredient tef3,uthrin* CE-810** montmori lion ite, clay We, is h t 3.*26 7.00 89-74 *92% purity **from Proctor cOamble; ontainoi primarily methyl caprylate and methyl caprate 9 Example 12 Ingredient WeiQht% tefluthrin* 8,15 CE-810 17.50 montmorillonite clay 89.74 92% purity In storage stability tests, compositions produced according to this invention, including compositions of the above examples, showed a reasonable stability f'r periods of up to three months at temperatures of betweent 4 and 50 0

C.

Compositions of this invention have shown satisfactory control of Western Spotted Cucumber Beetle larvae and eggs, and other insects.

In a test for mammalian toxicity, a composition according to this invention containing (by weight) tefluthrin (technical grade), 10.00% methyl oleate and 88.5% montmorillonite clay demonstrated very low eye irritation in rabbits; on tests of six rabbits, only moderate irritation was seen this composition falls into Toxicity Category III.

-I

Claims (17)

1. A water insoluble granular sotl insecticide composition free of surfactants and dispersing agents comprising from about 0.1 to about 30 weight percent of a pyrethroid insecticide, from about 1 to about 30 weight percent of a Cl-C 4 alkyl ester of a fatty acid having from 8 to 18 carbon atoms, or a mixture of such esters, and supported on a granular support consisting essentially of a) a clay; b) a granular material ,her than clay selected from the group consisting of diatomaceous earth, corn cob, peanut hulls, wood pulp and other cellulosic materials; or c) a mixture of clay and said granular material other than clay. i0

2. A composition according to Claim 1 further comprising a stabilizer and/or anti-oxidant.

3. A composition according to Claim 1 or Claim 2 comprising from about 0.6 to about 25 weight percent of an insecticide, and from about 6 to about 21 weight percent of C -C 4 alkyl ester of a fatty acid having from 8 to 18 carbon atoms, or mixture of such esters.

4. A composition according to Claim 3 comprising from about 1 to about weight percent of an insecticide, and from about 7 to about 18 weight percent of a Ci-C 4 alkyl ester of a fatty acid having from 8 to 18 carbon atoms, or mixture of such esters.

5. A composition according to any one of the preceding claims in which the ester is a methyl ester or a mixture of methyl esters.

6. A composition according to Claim 5 in which the ester is selected from methyl caprate, methyl caprylate, methyl oleate, methyl laurate, methyl stearate, the methyl ester of rapeseed oil fatty acid and mixtures of two or more thereof.

7. A composition according to any one of the preceding claims in which the insecticide is tefluthrin.

8. A composition according to Claim 1 in which the ester comprises methyl oleate.

9. A composition according to Claim 7 in which the ester comprises primarily o1 methyl oleate. A composition according to Claim 1 in which the ester comprises methyl caprylate and methyl caprate.

R/ ,'j I I -11- 590 4411i Al 9919" io=§9, I•PO

11. A composition according to Claim 1 in which the ester comprises the methyl ester of rapeseed oil fatty acid.

12. A composition according to any one of the preceding claims in which the granular support is a clay.

13. A composition according to any one of the preceding claims in which the granular support is montmorillonite clay.

14. A composition according to any one of Claims 1 to 11 in which the granular o0 support is a material other than clay.

A composition according to any one of Claims 1 to 11 in which the granular support is a combination of a clay and a material other than clay.

16. A composition according to any one of the preceding claims further comprising a stabilizer and/or antioxidant selected from polyalkylene glycols, s15 propyl gallate, BHT, DHA, tall oil rosin, tertiary butyl hydroquinone, natural tocopherols and mixtures of two or more of the above.

17. A composition according to Claim 1 as substantially as hereinbefore described with reference to any one of the examples. S S 20 DATED: 8 January, 1997 PHILLIPS ORMONDE FITZPATRICK aAttorneys for: 25 ZENECA LIMITED "ft y -f A 12 GRANULAR PESTICIDE COMPOSITIONS Abstract Granular pesticidal formulations contain a C I-C4 alkyl este.- of a fatty acid having from 8 to 18 carbon atoms, or a m2ixtiire of such esters. .111 *so. 5* 5* S S SO S OS