Fungizides Pflanzenschutzmittel

Insoluble or slightly soluble salts of a 1-lower alkyl-3-higher alkyl benzimidazole of formula: in which R1 is a C1-C4 alkyl radical, R2 is H or a C1-C4 alkyl radical, R3 is a C8-C20 alkyl radical, R4 is H or a C1-C4 alkyl radical, a C1-C4 alkoxy radical, a chlorine atom or a nitro group, X is a salt-forming radical as hereinafter defined, and n is a whole number equal to the valency of the anion X, are prepared by reacting a soluble salt of a 1-lower alkyl-3-higher alkyl-benzimidazole with a salt of the formula MenX, in which Me is an alkali metal. X is a chloride, bromide, sulphate, nitrate, hexacyanoferrate, reineckate, dihydronaphthalene-1,5-disulphonate, (di)-nitrophenylsulphonate, pentachlorophenate, 2-mercaptobenzimidazolate or 2-mercapto-benzothiazolate ion. The compounds are used in fungicidal compositions.ALSO:Fungicidal compositions comprise minor amounts of compounds of formula in which R1 is a C1-C4 alkyl radical, R2 is H or a C1-C4 alkyl radical, R3 is a C8-C20 alkyl radical, R4 is H or a C1-C4 alkyl or alkoxy radical, a chlorine atom or a nitro group, X is an ion as defined below and n is a whole number equal to the valency of the anion X, incorporated in a major amount of an inert solid or liquid diluent or carrier. X may be a chloride, bromide, sulphate, nitrate, hexacyanoferrate, reineckate, dihydro-naphthalene - 1,5 - disulphonate, (di) - nitrophenyl-sulphonate, pentachloro-phenate, 2-mercaptobenzimidazolate or 2-mercapto-benzothiazolate radical. The compositions may be sprayed in a dispersed or emulsified form or applied as dusts. When sprayed, the compounds are ground with suitable wetting and dispersing agents in the presence of inert materials, such as kaolin or talc, or together with emulsifiers dissolved in suitable solvents. They may be applied with other fungicides and/or insecticides. In an example, the compounds are used in the form of an aqueous emulsion. Auxiliary solvents such as dimethyl formamide, chlorobenzene and acetone may be used in the formation of the emulsions and a non-ionic emulsifier such as an aryl-hydroxypolyglycol ether may also be added.