DE2306043A1 - HERBICIDE - Google Patents

Description

Badische Anilin- & Soda-Fabrik AG 2306043

Our reference: O.Z. 29 694 Sws / Wil 67OO Ludwigshafen, 5-2.1973

herbicide

The present invention relates to a new valuable herbicidal mixture in solid form, with a high active ingredient content, and to its use as a herbicide.

The use of 1-phenyl-4-amino-5-chloropyridazon- (6), 2,3-dichloroallyl- and 2,3,3-trichloroallyl-N, N-diisopropylthiol carbamate is known as herbicides.

A liquid mixture of 1-phenyl-4-amino-5-chloropyridazon- (6) and 2,3-dichloroallyl-N, N-diisopropyl-thiolcarbamate is also known (DT-PS 1 216 010). The disadvantage of this mixture is the low active ingredient concentration of 20 wt.% (Calculated on the total mixture) in this mixture.

It has been found that the active ingredient content of the mixture, with an unchanged biological activity is substantially higher when the herbicide (calculated on the final mixture) is more than 20 # wt. Of a mixture in solid form from 10 to 60 wt.% L-phenyl-4 -amino-5-chloro-pyridazone (6) and adsorbed on a solid carrier 10 to 50 wt.% 2,3-dichloroallyl-N-diisopropylthiolcarbamat and / or 2,3,3-trichloroallyl-N-diisopropylthiolcarbamat. The solid carrier is expediently a highly adsorptive carrier. Adsorption can be carried out in such a way that the 2,3-dichloro-allyl derivative, which is liquid at room temperature, is mixed directly with the carrier substance, the 2,3,3-trichloroallyl derivative, which is solid at room temperature, is mixed as a melt at a slightly elevated temperature in a mixer will. Highly adsorptive carrier substances which are suitable for this purpose are, for example, silicas or gels with a BET surface area of at least 100 m / g, preferably those with more than 200 m / g are used. It is possible in this V / else to prepare mixtures with more than 20 wt.% Active ingredient.

784/72 / 2

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The BET method is a gas adsorption measuring method for determining inner and outer surfaces (J-. Arner, Chem. Soc. 5 £, 2682 (1957) and 60, 309 (1938)).

The solid carrier present in the herbicide according to the invention should be in finely divided form. By this we mean particles with a size of 10 ^J ' to 10 mm, in particular

- ~% -2 "■ special from 10 to 10 mm.

It is preferably used as a finely divided, solid carrier Used silica gel. The stability of the mixtures according to the invention is extremely good »

The herbicide is suitable for combating undesirable Plants. It is used in the usual way, for example by dusting, spraying or spraying.

The ratio of liquid active ingredient to solid carrier can be in the range of 10 to ^ O parts by weight of active ingredient 90 to 60 parts by weight of carrier material vary. The mixture preferably contains 25 parts by weight of active ingredient as a mixture with 75 parts by weight of solid carrier.

The stable mixtures according to the invention can additionally wetting agents or dispersants which are customary in addition to the substances mentioned so far contain.

The mixtures according to the invention are prepared by the mixture components active ingredient and solid carrier and optionally further mixture components, such as others Active ingredients, wetting and dispersing agents, advantageously in finely divided form he shape, intensively mixed with each other and, if necessary, finely ground. The mixture can be used in conventional mixing devices, for example a ribbon mixer. It is advisable to see when mixing and possibly grinding to avoid heating the mixture above about 60 ° C. the Mixing components are mixed together in the mixing device for about] 50 minutes to 3 hours, depending on the quantity and intensity mixed and are then suitable for longer storage

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suitable.

Another advantage of the mixtures according to the invention lies in that the relatively volatile thiol arbamates through the volatility of the adsorption is greatly reduced, so that it does not occur so quickly after spraying on the field must be worked into the soil, as is necessary with the emulsion concentrates.

This reduction in the rate of evaporation can be seen in the following experiment:

On thin glass plates with a surface of approx. 8 cm 2,3-Dichlorallyl-diisopropylthiolcarbamate was used once as known aqueous emulsion and on the other hand as an aqueous suspension of the solid mixture according to the invention in the form of a applied throughout the film. After the water had evaporated, the platelets were placed on an electronic ultra-microbalance attached and a stream of air of constant strength and temperature passed it. The time-dependent weight loss of this The measuring plate was registered continuously. After 10 hours there were a film obtained from the known emulsion had been, 3. 10 "mg of active ingredient / cm evaporated while it was from a film consisting of a solid mixture according to the invention

-2 / 2 had been made, only 2. 10 mg / cm. The 2,3,3-trichloroallyl compound behaves accordingly. At the same time, therefore, significantly less evaporates from the solid mixture Active ingredient than from the liquid mixture.

The contents of active ingredients of the mixtures according to the invention are 10 to 60 wt.% L-phenyl-4-amino-5-chloro-pyridazone (6) and 10 to 50 wt.% 2,3-JDiallyl-N-diisopropylthiolcarbamat and / or 2 , 3 * 3-triehloroallyl-N-diisopropylthiol carbamate.

The weight percentages relate to the entire mixture. The rate of evaporation of the thiol arbamates is expediently reduced by 25 to 40 % by adsorption compared to the rate of evaporation of the liquid products.

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The following examples are intended to explain the invention (the parts are parts by weight).

Example 1 '

66.6 parts of 2,3-dichloroallyl-N-diisopropylthiol carbamate become on 33rd> 3 parts of precipitated silica with a surface after BET of 250 m / g, which is contained in a mixer, sprayed on and mixed well.

39 parts of 1-phenyl-4-amino-5-chloropyridazone- (6) are with 31.5 parts of this mixture with the addition of customary network and Dispersants and carriers supplemented to 100 parts, mixed and ground in conventional mills. The finished solid Mixture contains 39% by weight of the pyridazo derivative and 21% by weight of the thiol carbamate. .

The wettable powder obtained in this way has a good one herbicidal effect that of the corresponding liquid formulations, calculated on the same amount of active ingredient. His Storage and suspension stability corresponds to the usual ' Default. .

Example 2 '

Instead of 2,3-dichloroallyl-N-diisopropylthiol carbamate accordingly Example 1 are equal parts of 2,3,3-trichloroallyl-N-d ± isopropylthiol carbamate used. Then proceed as described in Example 1.

The above statements apply accordingly to the quality and effectiveness of this wettable powder.

/ 5 409835/0992

Claims (4)

- 5 - O, Z. 29 Claims (Ϊ). Herbicide containing more than 20 percent by weight of a Mixture in solid form from 10 to 60 percent by weight (calculated on the finished mixture) 1-phenyl-4-amino-5-chloropyridazon- (6) and adsorbs 10 to 50 percent by weight of 2, j5-dichloroallyl-N-diisopropylthiol carbamate on a solid carrier and / or 2, j5,> - trichloroallyl-N-diisopropylthiol carbamate. 2. Herbicide according to claim 1, characterized in that the solid carrier has a BET surface area of at least 100 mVg. 3. Herbicide according to claim 1 or 2, characterized in that the evaporation rate of the thiol carbamate is reduced by 25 to 40 % by adsorption. 4. Use of a herbicide according to claim 1 for combating unwanted plants = Badische Anilin- & Soda-Fabrik AG, - /, 09835/0992