GB1562908A

GB1562908A - Insecticidal compostions

Info

Publication number: GB1562908A
Application number: GB51428/76A
Authority: GB
Original assignee: Imperial Chemical Industries Ltd
Current assignee: Imperial Chemical Industries Ltd
Priority date: 1976-12-09
Filing date: 1976-12-09
Publication date: 1980-03-19
Also published as: ES464863A1; DK550577A; TR19735A; ZA777138B; NZ185797A; DD133889A5; OA05816A; CA1090249A; IL53471A0; NL7713586A; FR2373231B1; PH13582A; PL104152B1; HU175384B; FR2373231A1; DE2754507A1; PL202671A1; JPS5372822A; BE861368A; CS194825B2

Description

(54) INSECTICIDAL COMPOSITIONS (71) We, IMPERIAL CHEMICAL INDUSTRIES LIMITED, Imperial Chemical House, Millbank, London SWIP 3JF, a British company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to insecticidal compositions.

It is known to prepare insecticidal compositions in the form of emulsifiable concentrates in which an insecticidal active ingredient is mixed with an aromatic solvent based on alkylated benzenes (usually di- and trimethylbenzenes) and a surface active agent. When such concentrates are mixed with a large volume of water preparatory to spraying the presence of the surface active agent ensures that an emulsion is formed and the solvent and active ingredient remain uniformly distributed in the water for a sufficient time to enable the diluted composition to be applied by conventional spray equipment to a locus which it is desired to treat with the insecticide.

It has however been discovered that when such emulsifiable concentrates contain active ingredients selected from certain classes of insecticide they would be capable of inflicting serious ocular damage in mammals if accidentally brought into contact with the eyes.

This effect, which is characterised by severe eye irritation usually coupled with the onset of a pannus reaction (development of corneal opacity and the irreversible growth of healing tissue over the eye), could not have been predicted from the demonstrated toxic effects of either the aromatic solvent or the active ingredient in isolation, since both exhibit only mild irritation of the eye, without any pannus reaction. These unexpected and undesirable effects appear to be limited to insecticides of the types described in published British Patent Specifications Nos.

1,439,615, 1,413,491 and 1,448,228.

The present invention provides insecticidal compositions in the form of emulsifiable concentrates which consists essentially of (a) an active ingredient of the formula:-

wherein R is hydrogen or cyano, and R1 is either (i) a group of formula:-

wherein X is chlorine, or methyl, or (ii) a group of formula :

where Y and Z are both chlorine or both methyl, or Y is hydrogen and Z is methyl or a group of formula:-

where Q is bromine or chlorine; in association with (b) a liquid diluent consisting essentially of a major proportion of white oil and a minor proportion of an aromatic solvent based on alkylated benzenes; and (c) an anionic or non-ionic surface active agent; the white oil constituting from 35% to 75% w/v of the composition and the total of white oil and active ingredient constituting 55% to 85% w/v of the composition.

The compositions of the invention may be prepared by conventional mixing techniques and may be used to combat insect pests in the conventional manner, being diluted with water before use.

It has been surprisingly found that not only are the invention compositions much less hazardous to mammalian eye tissue, but also they are actually more efficacious in the control of insect pests than the conventional aromatic solvent based compositions.

Specific examples of insecticides which may be employed as active ingredients in the invention compositions include permethrin (3-phenoxybenzyl 3-(2,2dichlorovinyl)-2,2-dimethylcyclopropane carboxylate), cypermethrin (cr-cyano-3- phenoxybenzyl 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylate), phenvalerate (a-cyano-3-phenoxybenzyl 2-(4-chlorophenyl)-3-methylbutyrate), and decamethrin ((S)-cr-cyano-3-phenoxybenzyl (IR, R,3S)-3-(2,2-dibromovinyl)-2,2 dimethylcyclopropane carboxylate).

The active ingredient may conveniently be used in the form of'technical' grade material which is the form in which it is obtained in practice when manufactured, substantially free of gross impurities and solvents, and in all other respects suitable for formulation into compositions for use as insecticides or tickicides.

The term 'white oil' as used herein means refined paraffinic hydrocarbons boiling at a temperature greater than 300"C, and containing a high ( > 90%) unsulphonatable residue. Preferably the white oil has a greater than 95% unsulphonatable residue. A typical white oil suitable for use in the invention compositions has a distillation range as follows:- 10% point 310--3400C 50% point 350--3750C 80% point 3804000C Typical examples of suitable materials include those sold under the tradenames 'Puremor', 'Sunspray' 6N, and 'Risella' 17. ('Puremor', 'Sunspray' and 'Risella' are registered Trade Marks).

Surface active agents for use in the invention compositions are preferably of the anionic or non-ionic type. Suitable agents of the anionic type include for example soaps, salts of aliphatic monoesters of sulphuric acid, for example, salts of aliphatic monoesters of sulphuric acid, for example sodium lauryl sulphate; and salts of sulphonated aromatic compounds, for example dodecylbenzenesulphonate, sodium, calcium and ammonium lignosulphate, butylnaphthalene sulphonate, and a mixture of the sodium salts of diisopropyl- and triisopropylnaphthalenesulphonic acid. Suitable agents of the non-ionic type include, for example, the condensation products of ethylene oxide with fatty alcohols such as oleyl alcohol and cetyl alcohol, or with alkyl phenols such as octylphenol, nonylphenol, and octylcresol. Other non-ionic agents are the partial esters derived from long chain fatty acids and hexitol anhydrides, for example sorbitol monolaurate; the condensation products of the said partial esters with ethylene oxide and the lecithins.

More than one surface active agent may be used in the invention compositions to achieve the necessary emulsifying action and to optimise the behaviour of the dilute composition on the treated surface e.g. crop foliage.

The amount of surface active agent (or agents if more than one is used) will vary according to the amount of the other ingredients present, but is generally within the range 5 to 20% w/v, and preferably within the range 7 to 12% w/v of the emulsifiable concentrate.

The amount of aromatic solvent present in the concentrate varies principally with the choice and amount of active ingredient. Thus the active ingredients of the type represented by the foregoing formula wherein R is cyano are much less soluble in the white oil than those wherein R is hydrogen, and thus require the use of more aromatic solvent to achieve miscibility. The range is generally from about 10% to about 40% w/v, and preferably from 12 to 30% w/v. If less than 10% is used there is incomplete miscibility of the ingredients. Compositions comprising more than 40% of the aromatic solvent do not exhibit the reduction in ocular damage.

The concentrates may be prepared by simply mixing the various ingredients together. Preferably the active ingredient is dissolved in the aromatic solvent together with the surface active agent or agents and this mixture then diluted with the white oil.

The compositions thus produced are stable over long periods and may be diluted with water before being sprayed to combat insect pests.

Although the Examples given herein refer to various materials identified by their Trademarks, it is not intended to imply that the invention is limited solely to concentrates prepared using these materials. Thus alternative materials for use as surface active agents in the emulsifiable concentrates of the invention may be found, for example, by reference to McCutcheon's "Detergents and Emulsifiers" (1975 Edition) in Book I or Book II of the combined edition thereof (published by McCutcheon's Division, M C Publishing Company, Glen Rock, New Jersey, USA).

This reference also indicates the sources of the various Trademarked materials referred to in the Examples, with the exception of'Aromasol' H, which is an aromatic naphtha consisting of alkylated benzenes, principally the isomeric trimethylbenzenes along with a minor proportion of C, and C10 alkylated benzenes.

Alternatives to 'Aromasol' H include mixed xylenes, and an aromatic naphtha sold under the trademark 'Tenneco' 500/100.

The invention is illustrated by the following Examples.

EXAMPLE 1.

This Example illustrates an emulsifiable concentrate according to the invention. The following ingredients were mixed together in the proportions stated.

% w/v Permethrin (technical) 25.0 'Atlox'3404F 6.0 'Triton' X207 3.0 White Oil 45.0 'Aromasol' H to 100.0 ('Atlox','Triton' and 'Aromasol' are Registered Trade Marks).

EXAMPLE 2.

This Example illustrates another emulsifiable concentrate according to the invention.

% w/v Cypermethrin 10.0 'Atlox'3404F 7.2 'Triton' X207 1.8 White Oil 60.0 'Aromasol' H to 100.0 EXAMPLE 3.

This Example illustrates a further emulsifiable concentrate according to the invention.

% w/v Phenvalerate 25.0 'Atlox' 3404F 9.0 White Oil 45.0 'Aromasol' H to 100.0 EXAMPLE 4.

An emulsifiable concentrate according to the invention was prepared by mixing together the following ingredients in the proportions stated and then diluting the mixture with white oil until the total volume was 1 litre.

Permethrin (technical) 50 g 'Arylan' CA 36 g 'Synperonic' A4 54 g 'Aromasol' H 120 g The concentrate thus produced contained 5% w/v of permethrin and had a specific gravity of 0.88 at 1 50C.

EXAMPLE 5.

An emulsifiable concentrate comprising cypermethrin was prepared by mixing together the following ingredients. The white oil was added last.

% w/v Cypermethrin (technical) 25.0 'Atlox' 3404F 3.0 'Atlox' 3409F 4.5 'Aromasol' H 30.0 White oil to 100.0 The resulting concentrate possessed a specific gravity of 0.96 at 15 C.

EXAMPLE 6.

An omulsifiable concentrate according to the invention was prepared by mixing the following ingredients together in the proportions given, the white oil being added last.

% w/v Permethrin (technical) 10.0 'Atlox'3404F 7.2 'Triton' X207 1.8 'Aromasol' H 12.0 White oil to 100.0 The specific gravity of the concentrate was 0.90 at 150C.

EXAMPLE 7.

An emulsifiable concentrate containing 2% w/v permethrin was prepared by mixing together the following ingredients in the proportions given, the white oil being added last.

% w/v Permethrin (technical) 2.0 'Atlox'3404F 6.0 'Triton' X207 3.0 'Aromasol' H 10.0 White oil to 100.0 EXAMPLE 8.

The eye irritancy of the composition of Example 1 was determined in comparison with that of a standard emulsifiable concentrate of the conventional type having the following constitution.

% w/v Permethrin (technical) 25.0 'Acrylan' CA 7.5 'Synperonic' OPlO 12.5 2-Methoxyethanol 5.0 'Aromasol' H to 100.0 ('Arylan' and 'Synperonic' are Registered Trade Marks).

The tests were conducted using the procedure of Draize, J.H., (1959), Appraisal of the Safety of Chemicals in Foods, Drugs, and Cosmetics, Association of Food and Drug Officials of the United States, 46. The numerical scores obtained in these tests were interpreted and classified by the system described by Kay, J.H., and Calandra, J.C., (1962) J. Soc. Cosmet. Chem. 13, 6 to produce a grading on the Draize scale of 1 to 8 where 1 represents no effect and 8 represents severe eye damage. The results are given in the following table.

NUMERICAL SCORES Day Day Day Day Day Draize Formulation 1 2 3 6 7 Grading Standard EC 29 23 19.5 30* 15* 6 Example 1 EC 9.3 6 2.7 0 0 4 *The pannus reaction was observed to have set in on the 6th day. with the Standard EC. No such reaction was observed with the composition of the invention.

A grading of 6 indicates that the Standard EC is a severe irritant, whereas the grading of 4 for the composition of the invention indicates that it is only a mild irritant.

In a further series of tests other compositions of the invention were compared with standard emulsion concentrates containing no white oil. The results are set out in the following Table.

STANDARD EC INVENTION EC Active Draize Pannus Draize Pannus Ingredient (a.i.) % w/v a.i. i. Grading Reaction Grading Reaction Permethrin 24 6 Yes A No Permethrin 5 6 Yes 4 No Pennethrin 2 5 No A No Cyp exme thrin 10 6 Yes 5 No Similar tests have also shown that a conventional 30% emulsion concentrate (containing no white oil) of phenvalerate also gives a Draize grading of 6, as does a 1.25% standard emulsion concentrate of a-cyano-3-phenoxybenzyl (1 R.3S)-3-(2,2- dichlorovinyl)-2,2-dimethylcyclopropane carboxylate. These high Draize gradings and the onset of the pannus reaction could not have been predicted from the data for the technical grade active ingredient per se. These are given in the following Table.

Cis/Trans Draize Pannus Active Ingredients Ratio Grading Reaction Technical permethrin 2:3 3 No Technical permethrin 9:1 3 tAo Technical cypermethrin 2:3 4 No Technical cypermethrin 9:1 .4 No These tests clearly demonstrate that although the active ingredients per se do not present a serious hazard to eye tissue, when they are present in a composition comprising an aromatic solvent in certain proportions not only does the irritancy factor as measured on the Draize scale increase from slight or mild to severe but also in most cases there is also an onset of the pannus reaction. These undesirable hazardous effects are clearly mitigated by the inclusion of white oil in the compositions.

EXAMPLE 9.

This Example illustrates the superior insecticidal effect of the invention com position of Example 1 in a field trial comparison with the Standard EC described in Example 8.

(a) Cotton plants, infested with Heliothis armigera, Earias insulana, and Ostrinia nubilalis, were sprayed with aqueous compositions made by diluting the emulsifiable concentrates, at the flowering stage, 8 weeks and 9 weeks after sowing. The compositions contained 25, 50 and 100 ppm of the active ingredient. The number of damaged buds was assessed seven days later. Treatments which give less than 5% of damaged buds are considered satisfactory. The results are given in the following table.

Formulation Rate ppm Ss Damaged Buds Standard EC 25 15.1 50 6.6 100 2.5 Example 1 EC 25 5.8 50 4.6 100 4.6 Control. 36.7 (b) Vines infested with larval Lobesia botrana were sprayed with aqueous compositions of the EC's containing 20 and 30 ppm of active ingredient. The number of 3rd generation living caterpillars was assessed per 25 bunches of grapes.

No. of Caterpillars/ Formulation Rate ppm 25 bunches Standard EC 20 130 30 62.5 Example 1 EC 20 92.5 30 42.5 Control L 227.5

WHAT WE CLAIM IS: 1. An insecticidal composition in the form of an emulsifiable concentrate consisting essentially of (a) an active ingredient of formula:-

wherein R is hydrogen or cyano, and R1 is either (i) a group of formula:-

where X is chlorine, or methyl, or

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

position of Example 1 in a field trial comparison with the Standard EC described in Example 8.

(a) Cotton plants, infested with Heliothis armigera, Earias insulana, and Ostrinia nubilalis, were sprayed with aqueous compositions made by diluting the emulsifiable concentrates, at the flowering stage, 8 weeks and 9 weeks after sowing. The compositions contained 25, 50 and 100 ppm of the active ingredient. The number of damaged buds was assessed seven days later. Treatments which give less than 5% of damaged buds are considered satisfactory. The results are given in the following table.

Formulation Rate ppm Ss Damaged Buds Standard EC 25 15.1 50 6.6 100 2.5 Example 1 EC 25 5.8 50 4.6 100 4.6 Control. 36.7 (b) Vines infested with larval Lobesia botrana were sprayed with aqueous compositions of the EC's containing 20 and 30 ppm of active ingredient. The number of 3rd generation living caterpillars was assessed per 25 bunches of grapes.

No. of Caterpillars/ Formulation Rate ppm 25 bunches Standard EC 20 130 30 62.5 Example 1 EC 20 92.5 30 42.5 Control L 227.5

WHAT WE CLAIM IS: 1. An insecticidal composition in the form of an emulsifiable concentrate consisting essentially of (a) an active ingredient of formula:-

wherein R is hydrogen or cyano, and R1 is either (i) a group of formula:-

where X is chlorine, or methyl, or (ii) a group of formula:-

where Y and Z are both chlorine or both methyl, or Y is hydrogen and Z is methyl or a group of formula:-

where Q is bromine or chlorine; in association with (b) a liquid diluent consisting essentially of a major proportion of white oil and a minor proportion of an aromatic solvent based on alkylated benzenes; and (c) one or more anionic or non-ionic surface active agents; the white oil constituting from 35% to 75% w/v of the composition and the total of white oil and active ingredient constituting 55% to 85% w/v of the composition.
2. An insecticidal composition as claimed in Claim 1 wherein the active ingredient is permethrin, cypermethrin or decamethrin.
3. An insecticidal composition as claimed in Claim 1 wherein the active ingredient is phenvalerate.
4. An insecticidal composition as claimed in any one of Claims 1 to 3 in which the white oil is characterised in having an unsulphonatable residue of greater than 95%.
5. An insecticidal composition as claimed in any one of Claims 1 to 4 in which the white oil is characterised in having a distillation range in which the 10% point is in the range 310 to 3400C, the 50% point is in the range 350 to 3750C and the 80% point is in the range 380 to 4000 C.
6. An insecticidal composition as claimed in any one of Claims 1 to 5 wherein the surface active agent or agents are present in an amount within the range 5 to 20% w/v.
7. An insecticidal composition as claimed in Claim 6 wherein the surface active agent or agents are present in an amount within the range 7 to 12% w/v.
8. An insecticidal composition as claimed in any one of Claims 1 to 7 wherein the aromatic solvent is present in an amount within the range 10 to 40% w/v.
9. An insecticidal composition as claimed in Claim 8 wherein the aromatic solvent is present in an amount within the range 12 to 30% w/v.
10. Insecticidal compositions in the form of emulsifiable concentrates as claimed in Claim 1, substantially as described herein, with particular reference to any one of Examples 1 to 7.