Non-aqueous active ingredient concentrates having an herbicidal effect

Abstract

The present invention relates to active compound concentrates having herbicidal action, comprising a) from 10 to 100 g/l of at least one 4-benzoyl-substituted pyrazole compound of the formula I in which ##STR00001## R.sup.1, R.sup.3 independently of one another are hydrogen, halogen, methyl, halomethyl, methoxy, halomethoxy, methylthio, methylsulfinyl or methylsulfonyl; R.sup.2 is a 5-membered heterocyclic radical which is unsubstituted or carries 1, 2, 3 or 4 substituents selected from the group consisting of halogen, C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.4-alkoxy, C.sub.1-C.sub.4-haloalkyl, C.sub.1-C.sub.4-haloalkoxy and C.sub.1-C.sub.4-alkylthio; R.sup.4 is hydrogen, halogen or methyl; R.sup.5 is C.sub.1-C.sub.6-alkyl, C.sub.3-C.sub.6-cycloalkyl or C.sub.3-C.sub.6-cycloalkylmethyl; and R.sup.6 is hydrogen or C.sub.1-C.sub.4-alkyl; or one of its agriculturally useful salts, b) from 200 to 700 g/l of 2-chloro-N-(2,4-dimethyl-3-thienyl)-N-(2-methoxy-1-methylethyl)acetamide, and c) from 10 to 200 g/l of at least one surfactant S selected from a mixture of at least one anionic surfactant and at least one nonionic surfactant, where the components a), b) and c) are present dissolved in a mixture of organic solvents consisting to at least 95% by weight, based on the solvent mixture, of d1) at least one aprotic polar organic solvent having a miscibility with water at 25° C. and 1 bar of at least 50 g/l, and d2) at least one organic solvent having a solubility in water at 25° C. and 1 bar of less than 5 g/l.

Claims

1. A non-aqueous active compound concentrate comprising a) from 10 to 100 g/l of at least one 4-benzoyl-substituted pyrazole compound of the formula I or one of its salts ##STR00003##  in which R.sup.1 and R.sup.5 are each methyl; R.sup.3 is methylsulfonyl; R.sup.2 is 4,5-dihydroisoxazol-3-yl; and R.sup.4 and R.sup.6 are hydrogen, b) from 400 to 700 g/l of 2-chloro-N-(2,4-dimethyl-3-thienyl)-N-(2-methoxy-1-methylethy)acetamide, and c) from 10 to 200 g/l of at least one surfactant S selected from a mixture of at least one anionic surfactant and at least one nonionic surfactant, where the components a), b) and c) are present dissolved in a mixture of organic solvents containing at least 95% by weight, based on the solvent mixture, of d1) at least one aprotic polar organic solvent having a miscibility with water at 25° C. and 1 bar of at least 50 g/l, which is selected from the group consisting of dimethyl sulfoxide, N-methylpyrrolidone, N-ethylpyrrolidone, and mixtures thereof, and d2) at least one organic solvent having a solubility in water at 25° C. and 1 bar of less than 5 g/l, which is a hydrocarbon solvent; in which the anionic surfactant is selected from the group consisting of compounds comprising at least one SO.sub.3 group or one PO.sub.4 group and at least one aliphatic hydrocarbon radical having 8 to 22 carbon atoms or an araliphatic hydrocarbon radical having 10 to 24 carbon atoms and in which the nonionic surfactant comprises, as main component, at least one poly-C.sub.2-C.sub.3-alkylene glycol ether compound, where the weight ratio of apolar protic solvent to hydrocarbon solvent is from 1:10 to 10:1, and where the total amount of organic solvent is from 300 to 600 g/l.

2. The active compound concentrate according to claim 1, wherein the organic solvent has a solubility in water at 25° C. and 1 bar of less than 5 g/l is a hydrocarbon solvent and in which the weight ratio of aprotic polar solvent to hydrocarbon solvent is in the range of from 5:1 to 1:5.

3. The non-aqueous active compound concentrate of claim 1 in which the concentration of the at least one 4-benzoyl-substituted pyrazole compound of the formula I or its salt is from 20 to 100 g/l.

4. The non-aqueous active compound concentrate of claim 1 in which the concentration of the at least one 4-benzoyl-substituted pyrazole compound of the formula I or its salt is from 20 to 50 g/l.

5. The non-aqueous active compound concentrate of claim 1 in which the concentration of the 2-chloro-N-(2,4-dimethyl-3-thienyl)-N-(2-methoxy-1-methylethyl)acetamide is from 400 to 600 g/l.

6. The non-aqueous active compound concentrate of claim 4 in which the concentration of the 2-chloro-N-(2,4-dimethyl-3-thienyl)-N-(2-methoxy-1-methylethyl)acetamide is from 400 to 600 g/l.

7. The non-aqueous active compound concentrate of claim 1 wherein the aprotic polar organic solvent is N-methylpyrrolidone.

8. The non-aqueous active compound concentrate of claim 4 wherein the aprotic polar organic solvent is N-methylpyrrolidone.

9. A method for controlling unwanted vegetation which comprises preparing an aqueous spray liquor by diluting an active compound concentrate according to claim 1 and applying the spray liquor to act on plants, their seeds and/or their habitat and allowing the spray liquor to act on plants, their seeds and/or their habitat.

10. The method according to claim 9 which comprises treating the leaves of the unwanted plants with the aqueous spray liquor.

Description

(1) The examples below serve to illustrate the invention in more detail and are not to be understood as limitations.

(2) Feedstocks:

(3) Topramezone (active compound of the formula I, in which R.sup.1 and R.sup.5 are each methyl, R.sup.2 is 4,5-dihydroisoxazol-3-yl, R.sup.3 is methylsulfonyl, R.sup.4 and R.sup.6 are hydrogen); Dimethenamid-P Emulsifier 1: mixture of calcium dodecylbenzenesulfonate, castor oil ethoxylate, EO/PO triblock copolymer and the phosphate ester of a fatty alcohol having a surfactant content of ≧85% by weight Emulsifier 2: EO/PO triblock copolymer having a molecular weight of 6500 and a propylene oxide percentage of 50% by weight Emulsifier 3: sodium salt of a phenolsulfonic acid/formaldehyde condensate Emulsifier 4: mixture of poly(ethoxylate-co-propoxylates) of tristyrylphenol Thickener: xanthan-gum Defoamer: commercial polydimethylsiloxane/filler emulsion (Wacker Silikon SRE-PFL) (active content 20% by weight) Microbiocide: formulation comprising a mixture of 1,2-benzisothiazolin-3-one and 2-methyl-4-isothiazolin-3-one, active content 5% by weight (Aktizide MBS from Thor Chemie GmbH) Hydrocarbon solvent: aromatic hydrocarbon mixture having a content of aromatic compounds of at least 99% by weight and a minimum boiling point, determined according to ASTM 86 to 99, in the range of from 235 to 248° C. and a maximum boiling point in the range of from 290 to 305° C. (Solvesso® 200 from Exxon Mobil)

EXAMPLE 1

Preparation of a Non-Aqueous Active Compound Concentrate

(4) In a stirred tank, 219 g of N-methylpyrrolidone were initially charged, 32 g of topramezone were added and the mixture was stirred until a clear homogeneous mixture was obtained. With stirring, 219 g of hydrocarbon solvent, 32 g of topramezone 538 g of dimethenamid-P/l and 112 g of emulsifier 1 were added in succession, and the mixture was stirred until it was homogeneous. The mixture obtained was a reddish-brown liquid comprising 538 g of dimethenamid-P/l and about 32 g of topramezone/l.

(5) The density, determined at 20° C., was about 1.11 to 1.12 g/cm.sup.3. The viscosity, determined using a rotation viscosimeter according to OECD test procedure 114, was about 20 to 35 mPa.Math.s. After two weeks of storage at 54° C., the sample showed no visible changes. The foam height of a 0.3% by weight strength dilution, determined according to Ross-Miles (ASTM-D 1173 53) was not more than 30 mm. The emulsion stability according to CIPAC MT was 36.3.

EXAMPLE 2

Preparation of a Non-Aqueous Active Compound Concentrate

(6) In a stirred tank, 219 g of dimethyl sulfoxide were initially charged, 32 g of topramezone were added and the mixture was stirred until a clear homogeneous mixture was obtained. With stirring, 219 g of hydrocarbon solvent, 32 g of topramezone 538 g of dimethenamid-P/l and 112 g of emulsifier 1 were added in succession, and the mixture was stirred until it was homogeneous. The mixture obtained was a reddish-brown liquid comprising 538 g of dimethenamid-P/l and about 32 g of topramezone/l.

(7) The density, determined at 20° C., was about 1.11 to 1.12 g/cm.sup.3. The viscosity, determined using a rotation viscosimeter according to OECD test procedure 114, was about 20 to 35 mPa.Math.s. After two weeks of storage at 54° C., the sample showed no visible changes. The foam height of a 0.3% by weight strength dilution, determined according to Ross-Miles (ASTM-D 1173 53) was not more than 30 mm.

EXAMPLE 3

Preparation of a Non-Aqueous Active Compound Concentrate

(8) In a stirred tank, 219 g of N-methylpyrrolidone were initially charged, 32 g of topramezone were added and the mixture was stirred until a clear homogeneous mixture was obtained. With stirring, 219 g of hydrocarbon solvent, 32 g of topramezone 538 g of dimethenamid-P/l and 112 g of a mixture of calcium dodecylbenzenesulfonate and emulsifier 5 in a weight ratio of 1:1 were added in succession, and the mixture was stirred until it was homogeneous. The mixture obtained was a reddish-brown liquid comprising 538 g of dimethenamid-P/l and about 32 g of topramezone/l.

(9) The density, determined at 20° C., was about 1.11 to 1.12 g/cm.sup.3. The viscosity, determined using a rotation viscosimeter according to OECD test procedure 114, was about 20 to 35 mPa.Math.s.

EXAMPLE 4

Preparation of an Aqueous Active Compound Concentrate According to the Invention

(10) 1. In a stirred vessel, 400 g of demineralized water were initially charged, and 60 g of 1,2 propylene glycol, 20 g of emulsifier 3 and 166.7 g of an 18% by weight strength aqueous solution of emulsifier 2 were added successively. The mixture was stirred until a homogeneous clear solution was obtained, and 343.9 g of industrial-grade topramezone having a topramezone content of 97.7% by weight and 1 g of defoamer were then added successively. The suspension obtained in this manner was cooled to about 15° C. and then passed through a rotor/stator mill and subsequently, with cooling, through a bead mill until the desired particle size distribution was achieved. In this manner, an aqueous topramezone suspension was obtained in which 80% by weight of the particles had a diameter below 2 μm. 2. In a stirred vessel, 10 g of 1,2-propylene glycol and 119.4 g of demineralized water were initially charged, and 3 g of thickener and then 2 g of the microbiocide were then added successively with stirring. With stirring, the solution obtained in this manner was then added to the suspension obtained in step 1, and a further 4 g of the defoamer were then added with stirring. In this manner, an aqueous suspension was obtained which contained about 336 g of topramezone/1 and had a viscosity, determined according OECD 114, of about 60 to 100 mPa.Math.s. The particle size distribution was characterized by a d.sub.90 of ≦3.5 μm and a d.sub.50 of ≦1.3 μm. 3. With stirring, 44.4 g of 1,2-propylene glycol, 44.4 g of emulsifier 3 and 66.6 g of a 2% by weight strength aqueous solution of the thickener comprising 1.6% by weight of the biocide to 285.7 g of demineralized water. With stirring, 561 g of dimethenamid-P was added at 23° C. to this solution, and the mixture was stirred until a stable emulsion was obtained. Subsequently, 107.6 g of the suspension obtained in step 2 were added to the emulsion obtained in this manner, and stirring was continued for 10 minutes.

(11) In this manner, an aqueous suspoemulsion was obtained which had a dimethenamid-P content of about 538 g and a topramezone content of about 32 g/l. The density was about 1.11 g/cm.sup.3. The viscosity, determined using a rotation viscosimeter according to OECD test procedure 114, was about 70 to 90 mPa.Math.s. The d.sub.90 was below 7 μm and the d.sub.50 was below 1.5 μm. The pH of an about 1% by weight strength dilution in demineralized water was in the range of from about 2.5 to 4.5.