United States Patent 19
`Itzel et al.
`
`[11] Patent Number:
`[45] Date of Patent:
`
`4,892,866
`Jan. 9, 1990
`
`[54] STABILIZED PESTICIDAL COMPOSITION
`
`[56]
`
`[75]
`
`Inventors:
`
`Hanshelmut Itzel, Gau-Algesheim;
`Manfred Dewenter, Badenheim;
`Siegfried Henke, Welgesheim,all of
`Fed. Rep. of Germany
`
`[73] Assignee:
`
`Shell Internationale Research
`Maatsshappij B. V., The Hague,
`Netherlands
`
`[21] Appl. No.: 223,078
`
`[22] Filed:
`
`Jul. 22, 1988
`
`Foreign Application Priority Data
`[30]
`Aug. 7, 1987 [DE]
`Fed. Rep. of Germany....... 3726339
`
`[SU]
`[52]
`
`Tint, C04 casesccccesssssscsnssssssesnsssseseenee AOIN 57/00
`UWS. Che cescesssssccsessssesssssssseeeee 514/119; 514/970;
`514/971
`[58] Field of Search...............cc08 514/119, 970, 971
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`2,996,531
`3,090,719
`
`8/1961 YOUNG weccccsssssssssescssesesesesees 558/107 *
`5/1963 Pinemonti etal. .......s00 514/119
`
`FOREIGN PATENT DOCUMENTS
`
`237004 10/1985 Japan .
`791824
`3/1958 United Kingdom .
`903159
`8/1962 United Kingdom .
`
`Primary Examiner—Allen J. Robinson
`[57]
`_ ABSTRACT
`Theinvention provides a pesticidal composition com-
`prising, as active ingredient, dimethoate together with
`at least one inert carrier therefor, characterized in that
`the composition contains, as stabilizer, a cyclopropene
`fatty acid or an oil containing at least 1% w of a cyclo-
`propenefatty acid.
`
`4 Claims, No Drawings
`
`TIDE 1021
`
`1
`
`TIDE 1021
`
`

`

`4,892,866
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`5
`
`20
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`25
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`30
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`1
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`STABILIZED PESTICIDAL COMPOSITION
`
`2
`Pesticidal compositions comprise at least one active
`ingredient together with at least one inert carrier there-
`fore, preferably at least two carriers, at least one of
`which is a surface-active agent.
`Theinventionrelates to stabilised pesticidal composi-
`A carrier may be a solid or. liquid material, which
`tions, and moreparticularly to the stabilisation of pesti-
`may be inorganic or organic and of synthetic or natural
`cidal compositions containing dimethoate.
`origin. Typical solid carriers include natural and syn-
`Dimethoate,
`O,O-dimethyl-S-methylcarbamoyl-
`thetic clays andsilicates, for example natural silicas, for
`methyl phosphorodithioate, is a well-knownand widely
`example diatomaceous earths, and aluminium silicates,
`used systemic and contact insecticide. It is described,
`for example kaolinites, montmorillonites and micas.
`together with methods for its preparation, for example
`Typical liquid carriers are ketones, for example methyl-
`in UK Patent No. 791,824 and U.S. Pat. No. 2,996,531.
`naphthalenes, petroleum fractions, for example petro-
`Oneproblem of dimethoateis thatit is thermally unsta-
`leum xylenes and light mineral oils, and chlorinated
`ble and at temperatures of about 50° C. or moreit can be
`hydrocarbons, for example carbon tetrachloride. Mix-
`subject to uncontrolled thermal breakdown,resulting in
`tures of liquids are often suitable.-
`explosions. This is clearly a greater potential drawback
`One or more surface-active agents and/or stickers
`in hot climates, and particularly in developing countries
`can be included in a pesticidal composition. A surface-
`where storage facilities do not enable products to be
`active agent may be an emulsifying agentor a dispersing
`protected from the sun’s rays and where products are
`agent or a wetting agent; it may be non-ionic or ionic.
`liable to be transported in open trucks and stored tem-
`Anyof the surface-active agents usually applied in for-
`‘porarily in the open.
`mulating insecticides may be used. Examples of suitable
`In such conditions unprotected storage, or storage for
`surface-active agents are the sodium and calcium salts
`very long periods of time can easily result in products
`of polyacrylic acids and lignin sulphonic acids; the con-
`being unusable giving rise to problems of disposal, and
`densation products of fatty acids or aliphatic amines or
`in somecases fires have been caused by auto-ignition of
`amides containing at least 12 carbon atomsin the mole-
`stored products.
`cule with ethylene oxide and/or propylene oxide; fatty
`It has now surprisingly been found that when dimeth-
`acid esters of glycerol, sorbitan, sucrose or pentaeryth-
`oate is stored in admixture with an oil containing a
`ritol, condensates of these with ethylene oxide and/or
`cyclopropene fatty acid significantly reduced thermal
`propylene oxide; condensation products of fatty alco-
`degradation can be observed.
`hols or alkyl phenols, for example p-octylphenol or
`Accordingly the present invention provides a pestici-
`p-octylcresol, with ethylene oxide and/or propylene
`dal composition comprising, as active ingredient, di-
`oxide; sulphates or sulphonates of these condensation
`methoate together with at least one inert carrier there-
`products; alkali or alkaline earth metal salts, preferably
`for, characterised in that the composition contains, as
`sodium salts, of sulphuric or sulphonic acid esters con-
`stabiliser, a cyclopropene fatty acid or an oil containing
`taining at least 10 carbon atoms in the molecule, for
`at least 1% w of a cyclopropenefatty acid.
`example sodium lauryl sulphate, sodium secondary
`Typical examples of cyclopropene fatty acids are
`alkyl sulphates, sodium salts of sulphonated castoroil,
`malvalic acid (2-octyl-1-cylopropene-1-heptanoic acid)
`and sodium alkylaryl sulphonates, such as sodium dode-
`(otherwise also knownas malvic acid or halphen acid)
`cylbenzene sulphonate; and polymers of ethylene oxide
`and sterculic acid (2-octyl-1-cyclopropene-1-octanoic
`and copolymers of ethylene oxide and propylene oxide.
`acid) (also knownas sterculinic acid). Oils containing
`A pesticidal composition may for example be formu-
`these acids can be extracted from seeds of the kapok
`lated as a wettable powder, microcapsules, a dust, gran-
`tree (Cieba pentandra) (viz. kapok seed oil) and from
`ules, a solution, an emulsifiable concentrate, an emul-
`Sterculia species, particularly Sterculia foetida. These
`sion, a suspension concentrate or an aerosol. Composi-
`acids are also to be found in other plants, e.g. durian
`tions may have controlled release properties, or may be
`suitable for use as a bait.
`(Durio zibethinus), gnemon (Gretum gnemon) and in
`species of the Malvaceae family.
`Wettable powders usually contain 25, 50 or 75% w of
`Preferably the stabiliser in a composition of the in-
`active ingredient and may contain, in addition to inert
`vention comprises malvalic or sterculic acid or oil from
`solid material, 3-10% w of a dispersing agent and,
`seeds of the kapok tree or from Sterculia species. The
`where necessary, 0-10% w ofa stabiliser, a penetrant
`stabiliser may very conveniently be kapok seed oil.
`and/ora sticker. A dust is usually formulated as a dust
`It is preferred for. the weight ratio of cyclopropene
`concentrate having a composition similar to that of a
`fatty acid(s): dimethoate in a composition of the inven-
`wettable powderbut withouta dispersant, andis diluted
`tion to be in the range 0.1:1 to 1.5:1, more preferably
`in the field with further solid carrier to. give a composi-
`0.4:1 to 1:1, advantageously 0.5:1 to 0.7:1.
`tion usually containing 3-10% w ofactive ingredient.
`When the stabiliser in a composition of the invention
`Granules usually have a size in the range of from 10
`is kapok seed oil, the weight ratio kapok seed oil: di-
`to 100 BS mesh (1.676-0.152 mm) and may be manufac-
`methoate is preferably in the range 1:1 to 10:1, more
`tured by agglomeration or impregnation techniques.
`preferably 4:1 to 6:1.
`Generally, granules will contain 43-25% w active ingre-
`60
`The invention also provides a method ofstabilising a
`dient and 0-10% w of additives, for exampleastabiliser,
`pesticidal composition comprising, as active ingredient,
`slow release modifier and/or a binding agent.
`dimethoate together with at least oneinert carrier there-
`Emulsifiable concentrates usually contain, in addition
`for, the method comprising incorporating in the compo-
`to a solvent, and, when necessary, co-solvent, 10-50%
`sition, as stabiliser, a cyclopropene fatty acid or an oil
`w/v active ingredient, 2-20% w/v emulsifier and
`containing at least 1% w of a cyclopropenefatty acid.
`0-20% w/v of other additives, for example a stabiliser,
`Preferred methods of the invention employ the same
`a penetrant and/or a corrosion inhibitor. A suspension
`stabilisers and weight ratios as indicated abovein rela-
`concentrate is a stable, non-sedimenting, flowable prod-
`tion to compositions of the invention.
`uct and usually contains 10-75% w active ingredient,
`
`50
`
`35
`
`65
`
`-
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`2
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`

`

`4,892,866
`
`4
`temperatures for up to 36 months. Results are given in
`Table I following:
`
`TABLEI
`% breakdownof dimethoate
`
`37° Cc.
`A
`
`I
`
`50° C.
`A
`
`I
`
`60° C.
`A
`
`I
`
`0
`
`80
`
`11
`
`*
`
`0
`0
`0
`0
`0
`
`1
`10
`40
`70
`100
`
`Temperature
`Formulation
`
`20° Cc.
`(ambient)
`I
`A
`
`10
`
`Period (months)
`1
`6
`12
`10
`o
`24
`40
`o
`36
`*strongly exothermic breakdown
`
`The results given in Table I show the very much
`greater thermal stability conferred upon a formulation
`of dimethoate and cyclohexanonebytheinclusion of an
`oil (kapok oil). containing cyclopropenefatty acids.
`Weclaim:
`1. A pesticidal composition comprising, as active
`ingredient, a pesticidally effective amount of dimetho-
`ate together with at least one inert carrier therefor,
`characterized in that the composition containsa stabiliz-
`ing effective amountofa stabilizer comprising a cyclo-
`propene fatty acid, said stabilizer being selected from
`the group consisting of malvalic acid, sterculic acid, and
`oil from seeds of the kapok tree, from Sterculia species,
`from Durio zibethinus, from Gretym gnemon or from
`species of the Malvaceae family.
`2. A composition according to claim 1 wherein the
`stabilizer is selected from the group consisting of mal-
`valic acid, sterculic acid and oil from seeds of the kapok .
`tree or from Sterculia species.
`3. A composition according to claim 1 wherein the
`weightratio of cyclopropenefatty acid:dimethoateis in
`the range of 0.1:1 to 1.5:1.
`4. A composition accordingto claim 1, 2 or 3 wherein
`the stabilizer comprises oil from seeds of the kapoktree,
`the weight ratio of said oil:dimethoate being in the ©
`range of 1:1 to 10:1.*
`*£
`*©
`*&
`*&
`
`2
`
`35
`
`40
`
`45
`
`50
`
`35
`
`65
`
`3
`0.5-15% w of dispersing agent, 0.1~-10% w of suspend-
`ing agent, for example protective colloid and/ora thi-
`oxotropic agent, and 0-10% w ofother additives in-
`cluding, for example, a defoamer, a corrosion inhibitor,
`a stabiliser, a penetrant and/or a sticker, and as disper-
`sant, water or an organic liquid in which the active
`ingredient
`is substantially insoluble; certain organic
`additives and/or inorganic salts may be dissolved in the
`dispersant to assist in preventing sedimentation or as
`anti-freeze for water.
`The aqueous dispersions and emulsions formed by
`diluting a wettable powder or an emulsifiable concen-
`trate are themselves pesticidal compositions. Such dis-
`persions and emulsions may be of the water-in-oil or of
`the oil-in-water type, and may have a thick “mayon-
`naise’”’-like consistency.
`Pesticidal compositions may also contain other ingre-
`dients, for example, one or more other compoundspos-
`sessing pesticidal, herbicidal or fungicidal properties, or
`attractants, for example pheromones or food ingredi-
`ents, for use in baits and trap formulations.
`_ The invention also includes a method of combating
`pests at a locus which comprises applying to that locus
`a pesticidal composition according to the invention.
`The invention will be further understood from the fol-
`lowingillustrative Examples.
`EXAMPLE1
`
`A formulation of dimethoate was prepared by admix-
`ing components according to the following composi-
`tion.
`
` I
`
`Dimethoate
`Cyclohexanone
`Kapok seed oil
`(equivalent to 6-7% w/w
`cyclopropene fatty acids)
`
`%wiw
`11
`34
`55
`
`For comparison purposesstorage stability of formula
`I was monitored together with that of comparative
`formulation A, which consisted of 55.4% w/w dimeth-
`oate and 44.6% w/w cyclohexanone, over a range of
`
`3
`
`