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US-12616199-B2 - Crystallisation-free, highly concentrated suspension concentrates of metribuzin and diflufenican

US12616199B2US 12616199 B2US12616199 B2US 12616199B2US-12616199-B2

Abstract

The invention relates to the technical field of surfactant combinations combined with rheological modifiers combinations for crop protection formulations with increased shelf life and reduced crystallization, in particular herbicidal formulations, and formulations containing said surfactant combinations, as well as methods for producing said formulations.

Inventors

  • Arianna Martelletti

Assignees

  • BAYER AKTIENGESELLSCHAFT

Dates

Publication Date
20260505
Application Date
20200819
Priority Date
20190820

Claims (10)

  1. 1 . An aqueous agrochemical composition comprising: a1) 30%-35% (w/w) metribuzin; a2) 15%-20% (w/w) diflufenican in form of suspended particles; b) 1%-2% (w/w) of sodium lignosulfonates; c) 1%-2% (w/w) of non-ionic block copolymers of ethylene oxide and propylene oxide having a MW of about 12,000; d) at least one rheology modifier selected from the group consisting of: d1) 0.05%-0.15% (w/w) hydroxypropyl methylcellulose (HPMC), d1)+d2) 0.05%-0.15% (w/w) (HPMC) and 0.3%-0.7% (w/w) synthetic amorphous silica, d1)+d3) 0.05%-0.15% (w/w) (HPMC) and 0.1%-0.2% (w/w) xanthan gums, and d3) 0.1%-0.2% (w/w) of xanthan gums; e) 0.1%-0.3% (w/w) of citric acid; f) 5%-7% (w/w) of 1,2 propylene glycol; and g) water.
  2. 2 . The aqueous agrochemical composition according to claim 1 , wherein component d) is d3) only.
  3. 3 . The aqueous agrochemical composition according to claim 1 , wherein components b), c), d1), and e) are present in: b) 1.2% to 1.5% of sodium lignosulfonates, c) 1.2% to 1.5% of non-ionic block copolymers of ethylene oxide and propylene oxide having a MW of about 12,000, d1) 0.08%-0.12% of HPMC, and e) 0.17%-0.23% of citric acid.
  4. 4 . The aqueous agrochemical composition according to claim 1 , wherein component e) is present in e) 0.2% of citric acid.
  5. 5 . A product comprising the aqueous agrochemical composition according to claim 1 in an agrochemical formulation to stabilize metribuzin and diflufenican.
  6. 6 . A product comprising an aqueous agrochemical composition according to claim 1 for application in soybean.
  7. 7 . A product comprising an aqueous agrochemical composition according to claim 1 as fertilizer compatible compositions for tank mixing.
  8. 8 . The aqueous agrochemical composition according to claim 1 wherein the ratio of b) to c) is from 0.8:1 to 1:0.8.
  9. 9 . The aqueous agrochemical composition according to claim 8 , wherein the ratio of b) to c) is 1:1.
  10. 10 . The aqueous agrochemical composition according to claim 3 , wherein components b), c), d1), and e) are present in: b) 1.33% of sodium lignosulfonates, c) 1.33% of non-ionic block copolymers of ethylene oxide and propylene oxide having a MW of about 12,000, d1) 0.1% of HPMC, and (e) 0.2% of citric acid.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is the National Stage entry of International Application No. PCT/EP2020/073155, filed 19 Aug. 2020, which claims priority to European Patent Application No. 19192728.4, filed 20 Aug. 2019. BACKGROUND Field Surfactant and rheology modifiers combination for agrochemical (crop protection) formulations with increased shelf life and reduced crystallization, in particular for agrochemical formulations comprising metribuzin and diflufenican. The invention relates to the technical field of surfactant combinations combined with rheological modifiers combinations for crop protection formulations with increased shelf life and reduced crystallization, in particular herbicidal formulations, and formulations containing said surfactant combinations, as well as methods for producing said formulations. In a preferred embodiment, the instant invention relates to highly loaded aqueous formulations of herbicides, in particular aqueous formulations containing metribuzin and diflufenican. In particular, the invention relates to a high loaded suspension concentrate containing metribuzin and diflufenican with improved chemical and specifically physical stability. Description of Related Art To enhance the efficiency of applying herbicidal active ingredients, it is highly desirable to combine two or more active ingredients in a single formulation. Applying a combination of active ingredients with different modes of action can also provide for greater weed control. Concentrate compositions containing high loadings of multiple active ingredients are economical to transport and store. Concentrated compositions containing high loadings of multiple active ingredients (i.e., pre-mix concentrates) are also beneficial in avoiding or reducing mixing errors when preparing the application mixture in the field. Active substances can in principle be formulated in a great variety of ways, wherein the properties of the active substances and the nature of the formulation can lead to problems with regards to the processing, stability, usability and effectiveness of the formulations. In addition, for economic and ecological reasons certain formulations are more advantageous than others. Storage stability of suspended pesticide particles is a common problem in agrochemical formulation. Several additives and methods are known which try to avoid such problems. However, there is still the need to further improve the storage stability of such formulations. Apart from this, there is in general a demand for highly concentrated (highly loaded) formulations of active substances, since the higher concentration has many advantages. Thus, for example with highly concentrated formulations a lower expenditure on packaging is necessary than with less concentrated formulations. Similarly, the expenditure for production, transport and storage decreases; also, for example, the preparation of the spraying mixtures is simplified owing to the smaller quantities of for example pesticides which have to be handled, e.g. in the filling and mixing process. The active substances from the 1,2,4-triazinones group, such as metamitron and metribuzin, are highly effective herbicides with activity against harmful plants in plant crops. Metribuzin (IUPAC name: 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one; 4-amino-6-tert-butyl-3-methylthio-1,2,4-triazin-5(4H)-one) is a triazinone herbicide and has the following chemical structure: Metribuzin is an inhibitor of photosynthesis in plants. The compound can be absorbed by roots and leaves of the plants and then translocate in the xylem. Metribuzin is active in the control of grasses and broad-leaved weeds. Metribuzin is commercially available in herbicidal compositions and methods for its preparation are known in the art. Water-based formulations, such as aqueous suspension concentrates (SC), as a rule have the advantage that no organic solvents are required. Aqueous suspension concentrates for the formulation of agrochemically active substances are known. Thus, for example aqueous suspension concentrates of pesticides are described in WO 2011018188 A1 and EP 0110174 A1. In the latter a mixture of formaldehyde condensation products or lignosulfonates and wetting agents is preferably used. From US 2011/039704 A1 it is known that aqueous, aluminum silicate-free, highly concentrated suspension concentrates, containing the active substance metribuzin, one or more surfactants based on nonionic polymers from the ‘acrylic grafted polymers’ group, one or more rheology modifiers based on anionic heteropolysaccharides from the xanthan gum group can be prepared and are chemically and physically stable. Attempts on the basis of US 2011/039704 A1, which refers to the currently marketed formulation of aluminum silicate-free SC with 600 g/L metribuzin as active substance (corresponding to ca. 52.2 wt. %), to prepare a formulation with 600 g/L (in total) of a mixture of metribuz