Aqueous insecticidal compositions and the use thereof for protecting lignocellulose-containing materials

A method for protecting lignocellulosic materials against attack or destruction by harmful insects, comprising the treatment of the lignocellulosic material with an aqueous insecticide composition in the form of an aqueous dispersion of finely divided polymer particles which comprise at least one insecticidal organic active ingredient with a solubility in water of not more than 5 g/1 at 25° C. at 1013 mbar, said polymer particles having a mean particle size, determined by dynamic light scattering, of not more than 500 nm,

• where the polymer particles which comprise the at least one insecticidal active ingredient have a positive surface charge and where the aqueous dispersion of the active-ingredient-comprising polymer particles is obtained by subjecting a monomer composition of ethylenically unsaturated monomers M, in which the ethylenically unsaturated monomers M comprise the at least one insecticidal active ingredient in dissolved form, to radical aqueous emulsion polymerization,
• wherein the insecticidal active ingredient is selected among pyrethroids, carbamates, organo(thio)phosphates, arthropod growth regulators, pyrazole insecticides, abamectin, acequinocyl, amidrazone, amidoflumat, amitraz, azadirachtin, bifenazate, cartap, chlorfenapyr, chlordimeform, cyromazine, diafenthiuron, diofenolan, enamectin, endosulfan, fenazaquin, formetanate, formetanate-hydrochloride, hydramethylnon, indoxacarb, metaflumizon (4-{(2Z)-2-({4-(trifluoromethoxy)anilinol] carbonyl} hydrazono)-2-[3-trifluoromethyl)phenyl]ethyl}benzonitrile), pyridaben, pymetrozine, spinosad, tebufenpyrad, flupyrazaphos, flonicamid, flufenerim, flubendiamide, bistrifluron, NC512, benclothiaz, cyflumethofen, milbermectin, cyclometofen, lepimectin, profluthrin, dimefluthrin, N-ethyl-2,2-dichloro-1-methylcyclopropanecarboxamide-2-(2,6-dichloro-α,α,α-trifluroro-p-tolyl)phydrazone, N-ethyl-2,2-dimethylpropionamide-2-(2,6-dichloro-4-trifluoromethylphenyl)hydrazone, thiocyclam, pyridalyl, spirotetramat and neonicotinoids,
• wherein the monomers M comprise from 0.1 to 20% by weight based on the total amount of the monomers M of at least one monoethylenically unsaturated monomer M-k which is selected among monomers of the general formula I
• in which
• R1 is hydrogen or C1-C4-alkyl,
• R2, R3 independently of one another are C1-C4-alkyl and
• R4 is hydrogen or C1-C4-alkyl,
• Y represents oxygen, NH or NR5 wherein R5 is C1-C4-alkyl,
• A represents C2-C8-alkylene which is optionally interrupted by 1, 2 or 3 non-adjacent oxygen atoms, and
• X−represents an anion equivalent;
• wherein the monomers M further comprise from 60 to 99% by weight, based on the total amount of the monomers M, of at least one neutral monoethylenically unsaturated monomer M1 with a solubility in water of not more than 60 g/l at 25° C., which is selected from the group consisting of vinyl-aromatic monomers, C2-C10-alkyl acrylate and C1-C10-alkyl methacrylates.