WO2016008696A1

WO2016008696A1 - Agrochemical oil-in-water emulsion comprising silica particles and water-soluble nonionic emulsifier

Info

Publication number: WO2016008696A1
Application number: PCT/EP2015/064556
Authority: WO
Inventors: Helmut Auweter; Marc Nolte; Wen Xu; Megan RUMLEY; Kara Benton
Original assignee: Basf Se
Priority date: 2014-07-14
Filing date: 2015-06-26
Publication date: 2016-01-21

Abstract

The present invention relates to an oil-in-water emulsion comprising a pesticide which is dissolved in a water-immiscible solvent, hydrophobic modified silica particles, and a water-soluble nonionic emulsifier. Furthermore, the invention relates to a process for the preparation of said emulsion by contacting water, the pesticide, the water-immiscible solvent, the water-soluble nonionic emulsifier and the silica particles. Further subject matter are a method of controlling phytopathogenic fungi and/or undesired plant growth and/or undesired insect or mite attack and/or for regulating the growth of plants, wherein the emulsion is allowed to act on the respective pests, their environment or the crop plants to be protected from the respective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment; and seed containing said emulsion.

Description

Agrochemical oil-in-water emulsion comprising silica particles and water-soluble non-ionic emulsifier

Description

The present invention relates to an oil-in-water emulsion comprising a pesticide which is dissolved in a water-immiscible solvent, hydrophobic modified silica particles, and a water-soluble nonionic emulsifier. Furthermore, the invention relates to a process for the preparation of said emulsion by contacting water, the pesticide, the water-immiscible solvent, the water-soluble nonionic emulsifier and the silica particles. Further subject matter are a method of controlling phytopathogenic fungi and/or undesired plant growth and/or undesired insect or mite attack and/or for regulating the growth of plants, wherein the emulsion is allowed to act on the respective pests, their environment or the crop plants to be protected from the respective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment; and seed containing said emulsion. The present invention comprises combinations of preferred features with other preferred features.

Agrochemical emulsions comprising inorganic particles are known. WO2008/030749 discloses a pesticidal emulsion comprising an aqueous phase, a colloidal solid, and a dispersed oil emulsion phase.

Object of the present invention was to further improve agrochemical formulations, for example with regard to their storage stability, their rain fastness, and their biological activity.

The object was achieved by an oil-in-water emulsion comprising a pesticide which is dissolved in a water-immiscible solvent, hydrophobic modified silica particles, and a water-soluble nonionic emulsifier. An emulsion, such as an oil-in-water emulsion (EW) is typically a conventional type of formulation in the field of the agrochemical formulations. In EW formulations of a pesticide, the emulsion is preformed in the commercial product and is conventionally diluted with a carrier, such as water, when making up the spray mixture. The emulsion is an oil-in-water emulsion which may comprise an aqueous phase as the continuous phase and an oil phase as the disperse phase. The oil phase usually forms droplets within the aqueous phase. The oil phase usually comprises the water-immiscible solvent. The oil phase usually comprises the pesticide. The oil phase usually comprises the pesticide, which is dissolved in the water-immiscible solvent.

The pesticide is dissolved in the water-immiscible solvent. Preferably, the pesticide is present at least in the disperse phase of the emulsion. The emulsion may comprise a further pesticide. The further pesticide may be present in the oil phase and/or in the aqueous phase. The mean droplet size of the oil phase droplets is usually in the range of from 0.1 to 20 pm, in particular of from 0.3 to 10 pm and specifically of from 0.5 to 4.0 pm. The mean droplet size can be determined by particle-size measurement by means of laser diffraction, for example using a Malvern Mastersizer 2000.

The emulsion is an oil-in-water emulsion, which means for example that the emulsion comprises water. The emulsion can comprise at least 5% by weight, preferably at least 10% by weight and especially preferably at least 15% by weight of water based on the total weight of the emulsion. The emulsion can comprise from 20 to 85% by weight, preferably from 30 to 75% by weight and especially preferably from 35 to 70% by weight of water, based on the total weight of the emulsion.

The emulsion comprises a water-immiscible solvent. The water-immiscible solvent may be soluble in water at 20 °C up to 50 g/l, preferably up to 20 g/l, and in particular up to 5 g/l.

Suitable examples for water-immiscible solvents are

a hydrocarbon solvent such a an aliphatic, cyclic and aromatic hydrocarbons (e. g. toluene, xylene, paraffin, tetrahydronaphthalene, alkylated naphthalenes or their derivatives, mineral oil fractions of medium to high boiling point (such as kerosene, diesel oil, coal tar oils)); - benzyl acetate;

a vegetable oil such as corn oil, rapeseed oil;

a fatty acid ester such as Ci-Cio-alkylester of a Cio-C22-fatty acid; or

methyl- or ethyl esters of vegetable oils such as rapeseed oil methyl ester or corn oil methyl ester.

Mixtures of aforementioned solvents are also possible. Preferred solvents are aromatic hydrocarbons.

Suitable water-immiscible solvent are aromatic hydrocarbons. Aromatic hydrocarbons are compounds which consist of carbon and hydrogen and which comprise aromatic groups. Preferred are aromatic hydrocarbons or their mixtures with an initial boiling point of at least 160°C, preferably at least 180°C. Examples of aromatic hydrocarbons are benzene, toluene, o-, m- or p- xylene, naphthalene, biphenyl, o- or m-terphenyl, aromatic hydrocarbons which are mono- or polysubstituted by Ci-C2o-alkyl, such as ethylbenzene, dodecylbenzene, tetradecylbenzene, hexadecylbenzene, methylnaphthalene, diisopropylnaphthalene, hexylnaphthalene or decylnaphthalene. Others which are suitable are aromatic hydrocarbon mixtures with an initial boiling point of at least 160°C. Preferred aromatic hydrocarbons are aromatic hydrocarbon mixtures with an initial boiling point of at least 160°C, preferably at least 180°C. Mixtures of the above aromatic hydrocarbons are also possible. Usually, the emulsion comprises from 5 to 60% by weight, preferably from 15 to 55% by weight, especially preferably from 20 to 45% by weight of the water-immiscible solvent, in each case based on the total weight of the emulsion. The emulsion may comprise in addition to the water-immiscible solvent also a water-soluble solvent. The water-soluble solvent may be soluble in water at 20 °C more than 50 g/l, preferably more than 100 g/l. Usually, the emulsion comprises less than 10 % by weight, preferably less than 3 % by weight, especially preferably less than 1 % by weight of the water-soluble solvent, in each case based on the total weight of the emulsion. In one form the emulsion is essentially free of a water-soluble solvent.

The term pesticide refers to at least one active substance selected from the group of the fungicides, insecticides, nematicides, herbicides, safeners, biopesticides and/or growth regulators. Preferred pesticides are fungicides, insecticides, herbicides and growth regulators. Especially preferred pesticides are insecticides. Mixtures of pesticides of two or more of the abovemen- tioned classes may also be used. The skilled worker is familiar with such pesticides, which can be found, for example, in the Pesticide Manual, 16th Ed. (2013), The British Crop Protection Council, London. Suitable insecticides are insecticides from the class of the carbamates, organ- ophosphates, organochlorine insecticides, phenylpyrazoles, pyrethroids, neonicotinoids, spi- nosins, avermectins, milbemycins, juvenile hormone analogs, alkyl halides, organotin compounds nereistoxin analogs, benzoylureas, diacylhydrazines, METI acarizides, and insecticides such as chloropicrin, pymetrozin, flonicamid, clofentezin, hexythiazox, etoxazole, diafenthiuron, propargite, tetradifon, chlorofenapyr, DNOC, buprofezine, cyromazine, amitraz, hydramethyl- non, acequinocyl, fluacrypyrim, rotenone, or their derivatives. Suitable fungicides are fungicides from the classes of dinitroanilines, allylamines, anilinopyrimidines, antibiotics, aromatic hydrocarbons, benzenesulfonamides, benzimidazoles, benzisothiazoles, benzophenones, benzothi- adiazoles, benzotriazines, benzyl carbamates, carbamates, carboxamides, carboxylic acid dia- mides, chloronitriles cyanoacetamide oximes, cyanoimidazoles, cyclopropanecarboxamides, dicarboximides, dihydrodioxazines, dinitrophenyl crotonates, dithiocarbamates, dithiolanes, ethylphosphonates, ethylaminothiazolecarboxamides, guanidines, hydroxy-(2- amino)pyrimidines, hydroxyanilides, imidazoles, imidazolinones, inorganic substances, isoben- zofuranones, methoxyacrylates, methoxycarbamates, morpholines, N-phenylcarbamates, oxa- zolidinediones, oximinoacetates, oximinoacetamides, peptidylpyrimidine nucleosides, phenyla- cetamides, phenylamides, phenylpyrroles, phenylureas, phosphonates, phosphorothiolates, phthalamic acids, phthalimides, piperazines, piperidines, propionamides, pyridazinones, pyridines, pyridinylmethylbenzamides, pyrimidinamines, pyrimidines, pyrimidinonehydrazones, pyr- roloquinolinones, quinazolinones, quinolines, quinones, sulfamides, sulfamoyltriazoles, thia- zolecarboxamides, thiocarbamates, thiophanates, thiophenecarboxamides, toluamides, tri- phenyltin compounds, triazines, triazoles. Suitable herbicides are herbicides from the classes of the acetamides, amides, aryloxyphenoxypropionates, benzamides, benzofuran, benzoic acids, benzothiadiazinones, bipyridylium, carbamates, chloroacetamides, chlorocarboxylic acids, cy- clohexanediones, dinitroanilines, dinitrophenol, diphenyl ether, glycines, imidazolinones, isoxa- zoles, isoxazolidinones, nitriles, N-phenylphthalimides, oxadiazoles, oxazolidinediones, oxya- cetamides, phenoxycarboxylic acids, phenylcarbamates, phenylpyrazoles, phenylpyrazolines, phenylpyridazines, phosphinic acids, phosphoroamidates, phosphorodithioates, phthalamates, pyrazoles, pyridazinones, pyridines, pyridinecarboxylic acids, pyridinecarboxamides, pyrim- idinediones, pyrimidinyl(thio)benzoates, quinolinecarboxylic acids, semicarbazones, sulfonyla- minocarbonyltriazolinones, sulfonylureas, tetrazoli nones, thiadiazoles, thiocarbamates, tria- zines, triazinones, triazoles, triazolinones, triazolocarboxamides, triazolopyrimidines, triketones, uracils, ureas. The pesticide may comprise at least one water-insoluble pesticide. Water-insoluble pesticides may have a solubility in water of up to 10 g/l, preferably up to 1 g/l, and in particular up to 0.5 g/l, at 20 °C.

The pesticide may be soluble in the water-immiscible solvent (e.g. toluene), e.g. in an amount of at least 5 g/l, preferably at least 20 g/l and in particular at least 40 g/l, at 20 °C.

Usually, the emulsion comprises from 0.1 to 35% by weight, preferably from 0.5 to 20% by weight, especially preferably from 2 to 10% by weight of the pesticide, in each case based on the total weight of the emulsion.

The silica particles are hydrophobic modified. In general silica is hydrophilic due to silanol (Si- OH) groups on the surface of the particles. These silanol groups may be chemically reacted with various reagents to render the silica hydrophobic. The silica particles may be based on fumed or precipitated silica, where fumed silica is preferred.

The silica particles are preferably hydrophobic modified by treatment with a silanes, a siloxane, or a mixture thereof, whereas silanes or a mixture thereof are preferred. Examples for silanes or siloxanes are dimethyldichlorosilane, octamethylcyclotetrasiloxane, polydimethylsiloxane, oc- tylsilane, hexamethyldisiloxane, methacrylsilane.

Examples of silanes or siloxanes are 2-acetoxyethyltrichlorosilane, 2-acetoxyethyltriethox- ysilane, 2-acetoxyethyltrimethoxysilane, acetoxymethyltriethoxysilane, acetoxymethyltrimethox- ysilane, 3-acetoxypropyltrimethoxysilane, 3-acetoxypropylmethyldichlorosilane, 4-aminobutyltri- ethoxysilane, m-N-(2-aminoethyl)aminomethylphenethyltrimethoxysilane, p-N-(2-aminoethyl)- aminomethylphenethyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrihydroxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(6-aminohexyl)-3-aminopropyltriethox- ysilane, N-(6-aminohexyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrihydroxysilane, 3- aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-benzoylpropyltrimethoxysilane, benzyldimethylchlorosilane, benzyltrichlorosilane, benzyltriethoxysilane, benzyltrimethoxysilane, [1 ,3-bis(glycidyloxy)propy]ltetramethyldisiloxane, N,N-bis(2-hydroxyethyl)-3-aminopropyltrieth- oxysilane, o-bromophenyltrimethoxysilane, m-bromophenyltrimethoxysilane, p-bromophenyltri- methoxysilane, 3-bromopropyltrichlorosilane, 3-bromopropyltrimethoxysilane, 1 1 -bro- moundecyltrimethoxysilane, 1 1 -bromoundecyltrichlorosilane, tert-butyldiphenylmethoxysilane, tert-butyldiphenylchlorosilane, n-butyltrichlorosilane, tert-butyltrichlorosilane, n-butyltrimethox- ysilane, tert-butyltrimethoxysilane, methyl 3-trichlorosilylpropionate, trihydroxysilylacetic acid sodium salt, 4-chlorobutyldimethylchlorosilane, 2-chloroethyldichloromethylsilane, 2-chloro- ethylmethyldimethoxysilane, 2-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, chloromethyldimethylethoxysilane, chloromethyldimethylisopropoxysilane, chloromethyldime- thylchlorosilane, chloromethylmethyldiethoxysilane, chloromethylmethyldiisopropoxysilane, p- chloromethylphenyltrichlorosilane, p-chloromethylphenyltrimethoxysilane, chloromethyltri- chlorosilane, chloromethyltriethoxysilane, chloromethyltrimethoxysilane, o-chlorophenyltri- chlorosilane, m-chlorophenyltrichlorosilane, p-chlorophenyltrichlorosilane, o-chlorophenyltrieth- oxysilane, m-chlorophenyltriethoxysilane, p-chlorophenyltriethoxysilane, 3-chloropropyl- dimethylchlorosilane, chloropropyldimethylmethoxysilane, 3-chloropropylmethyldichlorosilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrichlorosilane, 3-chloropropyltriethoxy- silane, 3-chloropropyltrimethoxysilane, 2-[4-chlorosulfonylphenyl]ethyltrichlorosilane, 2-[4- chlorosulfonylphenyl]ethyltrimethoxysilane, 3-cyanobutyldimethylchlorosilane,

3-cyanobutylmethyldichlorosilane, 3-cyanobutyltrichlorosilane, 2-cyanoethylmethyl- dichlorosilane, 2-cyanoethyltrichlorosilane, 2-cyanoethyltriethoxysilane, 2-cyanoethyl- trimethoxysilane, 3-cyanopropyldimethylchlorosilane, 3-cyanopropylmethyldichlorosilane, 3- cyanopropylmethyldimethoxysilane, 3-cyanopropyltrichlorosilane, 3-cyanopropyltriethoxysilane, 3-cyanopropyltrimethoxysilane, 11 -cyanoundecyltrichlorosilane, 1 1-cyanoundecyl- trimethoxysilane, cyclohexyldimethylchlorosilane, cyclohexylmethyldichlorosilane, cyclohexyl- methyldimethoxysilane, (cyclohexylmethyl)trichlorosilane, cyclohexyltrichlorosilane, cyclohex- yltrimethoxysilane, cyclopentyltrichlorosilane, cyclopentyltrimethoxysilane, n-decyldi- methylchlorosilane, n-decylmethyldichlorosilane, n-decyltrichlorosilane, n-decyltriethoxysilane, di-n-butyldichlorosilane, di-n-butyldimethoxysilane, (dichloromethyl)methyldichlorosilane,

1 ,3-dichlorotetramethyldisiloxane, Ν,Ν-diethylaminomethyltriethoxysilane, diethyldichlorosilane, diethyldiethoxysilane, 2-(diethylphosphoryl)ethyltriethoxysilane, dimethyldihydroxysilane, di-n- hexyldichlorosilane, diisopropyldichlorosilane, diisopropyldimethoxysilane, 3-N,N-dimethyl- aminopropyltrimethoxysilane, dimethyldichlorosilane, dimethyldiethoxysilane, dimethyl- dimethoxysilane, 1 ,3-dimethyltetramethoxydisiloxane, 3-(2,4-dinitrophenylamino)propyl- triethoxysilane, di-n-octyldichlorosilane, diphenyldichlorosilane, diphenyldiethoxysilane, diphe- nyldimethoxysilane, diphenyldifluorosilane, diphenylmethylchlorosilane, diphenylmethyl- ethoxysilane, diphenyldihydroxysilane, docosylmethyldichlorosilane, docosyltrichlorosilane, do- decyldimethylchlorosilane, dodecylmethyldichlorosilane, dodecylmethyldiethoxysilane, dodecyl- trichlorosilane, dodecyltriethoxysilane, 3-N-ethylaminoisobutylmethyldiethoxysilane, 3-N- ethylaminoisobutyltrimethoxysilane, ethyldimethylchlorosilane, ethylmethyldichlorosilane, m- ethylphenethyltrimethoxysilane, ethyltriacetoxysilane, ethyltrichlorosilane, ethyltriethoxysilane, ethyltrimethoxysilane, 3-glycidyloxypropyldimethylethoxysilane, 3-glycidyloxy- propylmethyldiethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 3-glycidyloxypropyltri- ethoxysilane, 3-glycidyloxypropyltrimethoxysilane, n-heptylmethyldichlorosilane, n-heptyltri- chlorosilane, n-hexadecyltrichlorosilane, n-hexadecyltriethoxysilane, n-hexadecyltrimethox- ysilane, n-hexylmethyldichlorosilane, n-hexyltrichlorosilane, n-hexyltriethoxysilane, hydroxyme- thyltriethoxysilane, 3-iodopropyltrimethoxysilane, isobutyldimethylchlorosilane, isobutylmethyl- dimethoxysilane, isobutyltrichlorosilane, isobutyltriethoxysilane, isobutyltrimethoxysilane, 3-isocyanatopropyldimethylchlorosilane, 3-isocyanatopropyltriethoxysilane, 3-isocya- natopropyltrimethoxysilane, isooctyltrichlorosilane, isooctyltrimethoxysilane, isopropyldime- thylchlorosilane, isopropylmethyldichlorosilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(p-methoxyphenyl)propyl- methyldichlorosilane, 3-(p-methoxyphenyl)propyltrichlorosilane, 2-[methoxy(polyethyleneoxy)]- propyltrimethoxysilane, 3-methoxypropyltrimethoxysilane, 3-(N-methylamino)propyl- methyldimethoxysilane, 3-(N-methylamino)propyltrimethoxysilane, methyltribromosilane, methyl- trichlorosilane, methyltriethoxysilane, methyltrimethoxysilane, methyltrifluorosilane, methyltri-n- propoxysilane, tris(methoxyethoxy)methylsilane, n-octadecyldimethylchlorosilane, n-octadecyl- dimethylmethoxysilane, n-octadecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride, n- octadecylmethoxydichlorosilane, n-octadecylmethyldichlorosilane, n-octadecylmethyl- diethoxysilane, n-octadecylmethyldimethoxysilane, n-octadecyltrichlorosilane, n-octadecyl- triethoxysilane, n-octadecyltrimethoxysilane, S-(octanoyl)mercaptopropyltriethoxysilane, n- octyldimethylchlorosilane, n-octyldimethylmethoxysilane, n-octyltrichlorosilane, n-octyltri- ethoxysilane, n-octyltrimethoxysilane, n-pentyltrichlorosilane, n-pentyltriethoxysilane, 2- phenylethyltrichlorosilane, 2-phenylethyltrimethoxysilane, 3-phenoxypropyltrichlorosilane, 3-(N-phenylamino)propyltriethoxysilane, 3-(N-phenylamino)propyltrimethoxysilane, phenylme- thyldichlorosilane, phenylmethyldiethoxysilane, phenylmethyldimethoxysilane, phenyltri- chlorosilane, phenyltriethoxysilane, phenyltrifluorosilane, phenyltrimethoxysilane, n- propyldimethylchlorosilane, n-propylmethyldichlorosilane, n-propyltrichlorosilane, n- propyltriethoxysilane, n-propyltrimethoxysilane, 1 ,3-diethoxy-1 ,1 ,3,3-tetramethyldisiloxane, tet- ra-n-propoxysilane, 3-thiocyanatopropyltriethoxysilane, p-tolyltrichlorosilane, p- tolyltrimethoxysilane, triacontyldimethylchlorosilane, triacontyltrichlorosilane, tri-tert- butoxyhydroxysilane, 3-(2-sulfolanyloxyethoxy)propyltriethoxysilane, 3-(tert-butyloxy- carbonylamino)propyltriethoxysilane, 3-(ethyloxycarbonylamino)propyltriethoxysilane,

3-[(2-hydroxypolyethyleneoxy)carbonylamino]propyltriethoxysilane, 3-(triethoxysilylpropyl)-dihy- dro-3,5-furandione, (3,3,3-trifluoropropyl)trimethoxysilane, 3-(hydroxysulfonyl)- propyltrihydroxysilane, 3-(methylphosphonyl)propyltrihydroxysilane, triisopropylsilane, N-[(5- trimethoxysilyl)-2-aza-1 -oxypentyl]caprolactam, (3-trimethoxysilylpropyl)diethylene- triaminetriacetic acid trisodium salt, N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride, trimethylchlorosilane, trimethylbromosilane, trimethylethoxysilane, trimethylfluorosilane, trime- thyliodosilane, trimethylmethoxysilane, trimethyl-n-propoxysilane, triphenylchlorosilane, tri- phenylethoxysilane, triphenylhydroxysilane, 3-ureidopropyltriethoxysilane, 3- ureidopropyltrimethoxysilane, 1 ,1 ,1 ,3,3,3-hexamethyldisilazane, 1 ,3-di-n-butyl-1 ,1 ,3,3-tetra- methyldisilazane. It will be appreciated that it is also possible in accordance with the invention to use mixtures of silane compounds.

The silica particles may have a specific surface area (BET; Brunauer, Emmet and Teller) from 20 to 600 m²/g, preferably from 100 to 300 m²/g, and in particular from 150 to 250 m²/g. The specific surface area may be determined according to DIN ISO 9277.

The silica particles may have a carbon content from 0.1 to 12 wt%, preferably from 0.4 to 6.0 wt%, and in particular from 0.6 to 2.5 wt%. The carbon content may be determined according to DIN ISO 3262-20 chapter eight.

The primary particle diameter of the silica particles is in general in the range from

0.1 to 1000 nm, preferably from 1 to 100 nm, in particular from 3 to 30 nm. The primary particle diameter is preferably determined via transmission electron microscopy (TEM).

In general, a distinction is made in the case of particles between the primary and the secondary particle diameter. A plurality of smaller particles (having a primary particle

diameter) may agglomerate to form a larger particle (having a secondary particle

diameter). The secondary particle diameter can therefore often also be designated as agglomerate size.

The agglomerate particle diameter of the silica particles is in general in the range from 0.1 to 500 μιτι, preferably from 0.3 to 10 pm, in particular from 1 to 20 pm. The agglomerate particle diameter usually designates the mean particle diameter which is determined according to the volume fraction from the particle size distribution. Said particle size distributions can be measured by light scattering (for example on a Zetasizer Nano S apparatus from Malvern Instruments).

The hydrophobic modified silica particles (also known as "hydrophobic silica") are commercially available from various companies.

The emulsion may comprise 0.1 to 20 wt%, preferably 0.2 to 10 wt% and in particular 0.4 to 5 wt% of the silica particles.

The emulsion comprises a water-soluble nonionic emulsifier. Water-soluble nonionic emulsifiers may be selected from alkoxylates, preferably from compounds such as alcohols, alkylphenols, amines, amides, arylphenols, fatty acids or fatty acid esters which have been alkoxylated with 10 to 50 equivalents, where ethylene oxide and/or propylene oxide may be employed for the alkoxylation, preferably ethylene oxide.

In a form the water-soluble nonionic emulsifier contains C2-C3-polyalkoxylat.es of C10-C22- hydroxy fatty acid triglycerides, C2-C3-polyalkoxylates of Cio-C22-fatty acid mono- or diglycer- ides, or mixtures thereof, and where the average degree of alkoxylation (preferably of ethoxyla- tion) of the Cio-C22-hydroxy fatty acid triglycerides or Cio-C22-fatty acid mono- or diglycerides is usually from 10 to 150, preferably from 15 to 100, in particular from 20 to 70 and specifically from 30 to 65. In a preferred form the water-soluble nonionic emulsifier contains polyethoxylates of C12-C22- hydroxyfatty acid triglycerides, polyethoxylates of Ci2-C22-fatty acid mono- or diclycerides, or mixtures thereof, and where the average degree of alkoxylation (preferably of ethoxylation) of the Ci2-C22-hydroxyfatty acid triglycerides or Ci2-C22-fatty acid mono- or diclycerides is usually from 10 to 150, preferably from 15 to 100, in particular from 20 to 70 and specifically from 30 to 65.

In a preferred form the water-soluble nonionic emulsifier contains polyethoxylates of C12-C22- hydroxyfatty acid triglycerides, or mixtures thereof, and specifically polyethoxylates of castor oil, and where the average degree of of ethoxylation of the Ci2-C22-hydroxyfatty acid triglycerides (e.g. castor oil) is usually from 10 to 150, preferably from 15 to 100, in particular from 20 to 70 and specifically from 30 to 65. The water-soluble nonionic emulsifier may have an HLB value of at least 10, preferably of at least 12, and in particular of at least 13.5. The water-soluble nonionic emulsifier may have an HLB value of up to 20, preferably of up to 17, and in particular of up to 15.5. The HLB value may be determined according to the method of Griffin. The water-soluble nonionic emulsifier has usually a solubility in water of at least 5 g/l, preferably at least 20 g/l, and in particular at least 100 g/l, as may determined at 25 °C.

The water-soluble nonionic emulsifier is usually present in the aqueous phase of the oil-in-water emulsion. Preferably, the water-soluble nonionic emulsifier is present in dissolved form the aqueous phase of the oil-in-water emulsion.

Usually, the emulsion comprises from 0.1 to 15% by weight, preferably from 0.2 to 8 % by weight, especially preferably from 0.5 to 5% by weight of the water-soluble nonionic emulsifier, in each case based on the total weight of the emulsion.

The emulsion may comprise further nonionic emulsifiers beside the water-soluble nonionic emulsifier. The further nonionic emulsifiers are different from the water-soluble nonionic emulsifiers. The further nonionic emulsifier is usually water-insoluble. The further nonionic emulsifier has usually a solubility in water of below 5 g/l, below 20 g/l, orbelow 100 g/l, as may determined at 25 °C. The further nonionic emulsifier may have an HLB value of below 10, below 12, or below 13.5. Usually, the emulsion comprises from 0.1 to 20% by weight in each case based on the total weight of the emulsion.

In another form the oil-in-water emulsion comprises from 0.1 to 30 by weight of the pesticide (e.g. solubility in water of up to 10 g/l), 10 to 50% by weight of the water-immiscible solvent (e.g. aromatic hydrocarbons or benzyl acetate), 0.1 to 10% by weight of the silica particles, and 0.1 to 10% by weight of the water-soluble nonionic emulsifier, where the sum of these components is from 25 to 70 wt%, in each case based on the total weight of the emulsion. In another form the oil-in-water emulsion comprises from 0.5 to 20 by weight of the pesticide (e.g. solubility in water of up to 5 g/l), 15 to 45% by weight of the water-immiscible solvent (e.g. aromatic hydrocarbons or benzyl acetate), 0.2 to 7% by weight of the silica particles, and 0.2 to 7% by weight of the water-soluble nonionic emulsifier, where the sum of these components is from 30 to 70 wt%, in each case based on the total weight of the emulsion.

In another form the oil-in-water emulsion comprises from 1 to 10 by weight of the pesticide (e.g. solubility in water of up to 1 g/l), 20 to 40% by weight of the water-immiscible solvent (e.g. aromatic hydrocarbons or benzyl acetate), 0.4 to 5% by weight of the silica particles, and 0.5 to 5% g

by weight of the water-soluble nonionic emulsifier, where the sum of these components is from 35 to 65 wt%, in each case based on the total weight of the emulsion.

The emulsion may comprise auxiliaries for agrochemical formulations. Examples for suitable auxiliaries are surfactants, dispersants, wetters, adjuvants, solubilizers, penetration enhancers, protective colloids, adhesion agents, thickeners, humectants, repellents, attractants, feeding stimulants, compatibilizers, bactericides, anti-freezing agents, anti-foaming agents, colorants, tackifiers and binders. Suitable surfactants are surface-active compounds, such as anionic, cationic, and amphoteric surfactants, block polymers, polyelectrolytes, and mixtures thereof. Such surfactants can be used as dispersant, solubilizer, wetter, penetration enhancer, protective colloid, or adjuvant. Examples of surfactants are listed in McCutcheon's, Vol.1 : Emulsifiers & Detergents, McCutch- eon's Directories, Glen Rock, USA, 2008 (International Ed. or North American Ed.).

Suitable anionic surfactants are alkali, alkaline earth or ammonium salts of sulfonates, sulfates, phosphates, carboxylates, and mixtures thereof. Examples of sulfonates are alkylarylsulfonates, diphenylsulfonates, alpha-olefin sulfonates, lignine sulfonates, sulfonates of fatty acids and oils, sulfonates of ethoxylated alkylphenols, sulfonates of alkoxylated arylphenols, sulfonates of con- densed naphthalenes, sulfonates of dodecyl- and tridecylbenzenes, sulfonates of naphthalenes and alkylnaphthalenes, sulfosuccinates or sulfosuccinamates. Examples of sulfates are sulfates of fatty acids and oils, of ethoxylated alkylphenols, of alcohols, of ethoxylated alcohols, or of fatty acid esters. Examples of phosphates are phosphate esters. Examples of carboxylates are alkyl carboxylates, and carboxylated alcohol or alkylphenol ethoxylates.

Suitable cationic surfactants are quaternary surfactants, for example quaternary ammonium compounds with one or two hydrophobic groups, or salts of long-chain primary amines. Suitable amphoteric surfactants are alkylbetains and imidazolines. Suitable block polymers are block polymers of the A-B or A-B-A type comprising blocks of polyethylene oxide and polypropylene oxide, or of the A-B-C type comprising alkanol, polyethylene oxide and polypropylene oxide. Suitable polyelectrolytes are polyacids or polybases. Examples of polyacids are alkali salts of polyacrylic acid or polyacid comb polymers. Examples of polybases are polyvinylamines or pol- yethyleneamines. Suitable adjuvants are compounds, which have a negligible or even no pesticidal activity themselves, and which improve the biological performance of the compound I on the target. Examples are surfactants, mineral or vegetable oils, and other auxilaries. Further examples are listed by Knowles, Adjuvants and additives, Agrow Reports DS256, T&F Informa UK, 2006, chapter 5. Suitable thickeners are polysaccharides (e.g. xanthan gum, carboxymethylcellulose), anorganic clays (organically modified or unmodified), polycarboxylates, and silicates. Suitable bactericides are bronopol and isothiazolinone derivatives such as alkylisothiazolinones and benzisothiazolinones.

Suitable anti-freezing agents are ethylene glycol, propylene glycol, urea and glycerin.

Suitable anti-foaming agents are silicones, long chain alcohols, and salts of fatty acids.

Suitable colorants (e.g. in red, blue, or green) are pigments of low water solubility and water- soluble dyes. Examples are inorganic colorants (e.g. iron oxide, titan oxide, iron hexacyanofer- rate) and organic colorants (e.g. alizarin-, azo- and phthalocyanine colorants).

Suitable tackifiers or binders are polyvinylpyrrolidone, polyvinylacetates, polyvinyl alcohols, pol- yacrylates, biological or synthetic waxes, and cellulose ethers. The emulsion may be employed for the purposes of treatment of plant propagation materials, particularly seeds. The compositions in question give, after two-to-tenfold dilution, active substance concentrations of from 0.01 to 60% by weight, preferably from 0.1 to 40% by weight, in the ready-to-use preparations. Application can be carried out before or during sowing. Methods for applying or treating the emulsion on to plant propagation material, especially seeds include dressing, coating, pelleting, dusting, soaking and in-furrow application methods of the propagation material. Preferably, the emulsion is applied on to the plant propagation material by a method such that germination is not induced, e. g. by seed dressing, pelleting, coating and dusting. When employed in plant protection, the amounts of active substances applied are, depending on the kind of effect desired, from 0.001 to 2 kg per ha, preferably from 0.005 to 2 kg per ha, more preferably from 0.05 to 0.9 kg per ha, in particular from 0.1 to 0.75 kg per ha. In treatment of plant propagation materials such as seeds, e. g. by dusting, coating or drenching seed, amounts of active substance of from 0.1 to 1000 g, preferably from 1 to 1000 g, more preferably from 1 to 100 g and most preferably from 5 to 100 g, per 100 kilogram of plant propagation material (preferably seed) are generally required. When used in the protection of materials or stored products, the amount of active substance applied depends on the kind of application area and on the desired effect. Amounts customarily applied in the protection of materials are 0.001 g to 2 kg, preferably 0.005 g to 1 kg, of active substance per cubic meter of treated mate- rial.

Various types of oils, wetters, adjuvants, fertilizer, or micronutrients, and other pesticides (e.g. herbicides, insecticides, fungicides, growth regulators, safeners) may be added to the emulsion as premix or, if appropriate not until immediately prior to use (tank mix). These agents can be admixed with the compositions according to the invention in a weight ratio of 1 :100 to 100:1 , preferably 1 :10 to 10:1. The user applies the emulsion or the tank mix prepared from the emulsion usually from a pre- dosage device, a knapsack sprayer, a spray tank, a spray plane, or an irrigation system. Usually, the emulsion is made up with water, buffer, and/or further auxiliaries to the desired application concentration and the ready-to-use spray liquor or the agrochemical composition according to the invention is thus obtained. Usually, 20 to 2000 liters, preferably 50 to 400 liters, of the ready-to-use spray liquor are applied per hectare of agricultural useful area.

The present inventnion further relates to a method of preparing the emulsion by contacting water, the pesticide, the water-immiscible solvent, the water-soluble nonionic emulsifier and the silica particles, and optionally the auxiliaries. The contacting may be achieved in a known manner, such as described by Mollet and Grubemann, Formulation technology, Wiley VCH, Wein- heim, 2001 ; or Knowles, New developments in crop protection product formulation, Agrow Reports DS243, T&F Informa, London, 2005. Usually, the contacting is achieved by mixing (eg in a high shear mixer) at ambient temperatures (eg 10 to 40 °C).

The present inventnion further relates to a method of controlling phytopathogenic fungi and/or undesired plant growth and/or unde-sired insect or mite attack and/or for regulating the growth of plants, wherein the emulsion is allowed to act on the respective pests, their environment or the crop plants to be protected from the respective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment.

Examples of suitable crop plants are cereals, for example wheat, rye, barley, triticale, oats or rice; beet, for example sugar or fodder beet; pome fruit, stone fruit and soft fruit, for example apples, pears, plums, peaches, almonds, cherries, strawberries, raspberries, currants or goose- berries; legumes, for example beans, lentils, peas, lucerne or soybeans; oil crops, for example oilseed rape, mustard, olives, sunflowers, coconut, cacao, castor beans, oil palm, peanuts or soybeans; cucurbits, for example pumpkins/squash, cucumbers or melons; fiber crops, for example cotton, flax, hemp or jute; citrus fruit, for example oranges, lemons, grapefruit or tangerines; vegetable plants, for example spinach, lettuce, asparagus, cabbages, carrots, onions, tomatoes, potatoes, pumpkin/squash or capsicums; plants of the laurel family, for example avocados, cinnamon or camphor; energy crops and industrial feedstock crops, for example maize, soybeans, wheat, oilseed rape, sugar cane or oil palm; maize; tobacco; nuts; coffee; tea; bananas; wine (dessert grapes and grapes for vinification); hops; grass, for example turf; sweetleaf (Stevia rebaudania); rubber plants and forest plants, for example flowers, shrubs, deciduous trees and coniferous trees, and propagation material, for example seeds, and harvested produce of these plants.

The term crop plants also includes those plants which have been modified by breeding, mutagenesis or recombinant methods, including the biotechnological agricultural products which are on the market or in the process of being developed. Genetically modified plants are plants whose genetic material has been modified in a manner which does not occur under natural conditions by hybridizing, mutations or natural recombination (i.e. recombination of the genetic material). Here, one or more genes will, as a rule, be integrated into the genetic material of the plant in order to improve the plant's properties. Such recombinant modifications also comprise posttranslational modifications of proteins, oligo- or polypeptides, for example by means of gly- cosylation or binding polymers such as, for example, prenylated, acetylated or farnesylated residues or PEG residues.

The present inventnion further relates to seed containing the emulsion.

The advantages of the emulsion according to the invention are high storage stability, even at varying or low temperatures. In particular, no phase separation is observed during storage. The droplet size in the emulsion is small and/or stable. Moreover, the emulsion according to the invention permits, if required, the addition of large amounts of fat-soluble or water-soluble adjuvants in the oil phase or the aqueous phase. The good storage stability is retained even when such substances are added. Another advantage is the high rainfastness of the emulsion on the crops; a reduced toxicity; a reduced amount of emulsifiers and/or surfactants; a reduced spray drift, e.g. for ground or aerial spray application.

The examples which follow illustrate the invention without imposing any limitation. Examples

Hydrocarbon A: Aromatic hydrocarbon solvent, initial boiling point about 230 °C, aromatic content at least 99 vol%, flash point 100-1 10 °C.

Silica Particles: Silica particles, hydrophobic modified with hexadecyltrimethoxysilan, specific surface area (BET) about 175 to 205 m²/g, carbon content about 1.0 to about 1.7 wt%, primary particle diameter about 10-15 nm.

Antifoamer: Silicon defoamer.

Adjuvant A: Liquid ethoxylated and propoxylated C12-18 alcohol, water-insoluble, dynamic viscosity about 115-130 mPas at 23 °C.

Auxiliary A: Oleyl alcohol, ethoxylated with 3 units of ehtylene oxide, HLB 6-7, water-insoluble. Emulsifier A: Castor oil, ethoxylated with 50-60 units of ethylene oxide, HLB 14-15, melting point 30-35 °C, soluble in cold water.

Biocide: Aqueous mix of 2-methyl-4-isothiazolin-3-one and 1 ,2-benzisothiazolin -3-one.

Example 1

An alpha-Cypermethrin oil-in-water emulsion stabilized by the Silica Particles and the Emulsifier was prepared according to Table 1.

Table 1

The pesticidal oil-in-water emulsions were produced by the following procedure:

1. Alpha-Cypermethrin and the Auxiliary A are added to the Hydrocarbon A and stirred until they were dissolved (oil phase).

2. The Silica Particles, the Emulsifier A, propylene glycol and the Antifoamer were mixed with water to obtain uniformity (aqueous phase).

3. The oil phase was poured into the aqueous phase under agitation.

4. Homogenization was achieved my mixing with 2 minutes at 7000 rpm with a Silverson high shear mixer.

5. Droplet size was assessed and shearing continued until the oil droplet size reached a value below 3 micron.

6. Biocide and xanthan gum were added and mixed.

The storage stability was tested with a sample at 54 °C for two weeks, with another sample in a daily cycling temperature from -10 °C to +10 °C for two weeks, and with another sample at -10 °C for two weeks.

The emulsion stability was determined by visual observation of the samples. No noticeable phase separation occurred.

The oil droplet size was measured before / after storage by a Malvern^® Mastersizer 2000. No droplet size increase was observed.

Therefore, the alpha-Cypermethrin oil-in-water emulsion is physically stable.

A dilution stability test in 342 ppm standard hard water, calculated as calcium carbonate, was also carried out. One milliliter of the sample emulsion was mixed with 99 ml of the standard hard water. The visual observation of the sample was performed after 24 h standing. No settlement, creaming or phase separation was observed. Therefore, the alpha-Cypermethrin oil- in-water emulsion is physically stable in hard water after dilution. Example 2

A Chlorfenapyr oil-in-water emulsion with the following composition was prepared as described in Table 2:

Table 2

The pesticidal oil-in-water emulsions were prepared according to example 1. Adjuvant A was also dissolved in step 1. in the oil phase.

The oil droplet size was measured before / after storage by a Malvern^® Mastersizer 2000. No droplet size increase was observed. Therefore, the Chlorfenapyr oil-in-water emulsion is physically stable. A dilution stability test in 342 ppm standard hard water, calculated as calcium carbonate, was also carried out. One milliliter of sample D was mixed with 99 ml of 342 ppm standard hard water. The visual observation of the sample was performed after 24 h standing. No settlement, creaming or phase separation was observed. Therefore, the Chlorfenapyr oil-in-water emulsion is physically stable in hard water after dilution. Example 3

A Pyraclostrobin oil-in-water emulsion with the following composition was prepared according to Table 3:

Table 3

The pesticidal oil-in-water emulsions were prepared according to example 1 .

The storage stability was tested with a sample at 54 °C for two weeks, with another sample in a daily cycling temperature from -10 °C to +10 °C for two weeks, with another sample at -10 °C for two weeks, and with another sample at 21 °C for two weeks.

The oil droplet size was measured before / after storage by a Malvern^® Mastersizer 2000. No droplet size increase was observed. Therefore, the Pyraclostrobin oil-in-water emulsion is physically stable. The emulsion stability was determined by visual observation of sample phase separation after storage, as well as the increase of the oil droplet size before / after storage at different storage temperatures. Therefore, the Pyraclostrobin oil-in-water emulsion is physically stable.

A dilution stability test in 342 ppm standard hard water, calculated as calcium carbonate, was also carried out. One milliliter of sample D was mixed with 99 ml of 342 ppm standard hard water. The visual observation of the sample was performed after 24 h standing. No settlement, creaming or phase separation was observed. Therefore, the Pyraclostrobin oil-in-water emulsion is physically stable in hard water after dilution.

Claims

1. An oil-in-water emulsion comprising a pesticide which is dissolved in a water-immiscible solvent, hydrophobic modified silica particles, and a water-soluble nonionic emulsifier.

2. The emulsion according to claim 1 , where the emulsion comprises from 0.1 to 10 wt% of the silica particles.

3. The emulsion according to claim 1 or 2, where the silica particles have a specific surface area from 100 to 300 m²/g.

4. The emulsion according to claims 1 to 3, where the silica particles have a primary particle diameter of about 1 to 50 nm.

5. The emulsion according to claims 1 to 4, where the silica particles are hydrophobic modified by treatment with a silanes, a siloxane, or a mixture thereof.

6. The emulsion according to claims 1 to 5, where the solvent is a hydrocarbon solvent, benzyl acetate, a vegetable oil, a fatty acid ester, a methyl- or ethyl esters of vegetable oils, or a mixture thereof.

7. The emulsion according to claims 1 to 6, where the solvent is an aromatic hydrocarbon or benzyl acetate.

8. The emulsion according to claims 1 to 7 comprising 30 to 75 wt% of water.

9. The emulsion according to claims 1 to 8, where the emulsion comprises from 15 to 55 wt% of the water-immiscible solvent.

10. The emulsion according to claims 1 to 9, where the pesticide comprises a water-insoluble pesticide.

1 1. The emulsion according to claims 1 to 10, where the water-soluble nonionic emulsifier has a solubility in water of at least 5 g/l at 25 °C.

12. The emulsion according to claims 1 to 1 1 , where the water-soluble nonionic emulsifier has an HLB value of at least 10.

13. The emulsion according to claims 1 to 12, where the water-soluble nonionic emulsifier

comprises C2-C3-polyalkoxylat.es of Cio-C22-hydroxy fatty acid triglycerides, C2-C3- polyalkoxylates of Cio-C22-fatty acid mono- or diglycerides, or mixtures thereof, and where the average degree of alkoxylation of the Cio-C22-hydroxy fatty acid triglycerides or C10-C22- fatty acid mono- or diglycerides is from 10 to 150.

14. A method of preparing the emulsion according to any of claims 1 to 13, by contacting water, the pesticide, the water-immiscible solvent, the water-soluble nonionic emulsifier and the silica particles.

15. A method of controlling phytopathogenic fungi and/or undesired plant growth and/or undesired insect or mite attack and/or for regulating the growth of plants, wherein the emulsion as defined in any of claims 1 to 13 is allowed to act on the respective pests, their environment or the crop plants to be protected from the respective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment.