INSECTICIDAL FORMULATION FOR VECTOR AND PEST CONTROL WITH INCREASED CONTACT EFFICACY

Abstract

The present invention relates to insecticidal formulations for vector and pest control with increased contact efficacy, more particularly to insecticidal active ingredient—matrix particles and insecticidal compositions comprising such insecticidal active ingredient—matrix particles, as well as to methods and uses of such insecticidal formulations.

Claims

1. Insecticidal active ingredient—matrix material particles with a particle size d50 of 0.1 to 75 microns, comprising a) at least one insecticidal active ingredient selected from the group consisting of isoxazolines, meta-diamides, arylpyrazolheteroarylamides and arylpyrazolarylamides, wherein the at least one insecticidal active ingredient is distributed in b) a matrix material comprising a wax.

2. Insecticidal active ingredient—matrix material particles with a particle size d50 of 0.1 to 75 microns comprising a) at least one insecticidal active ingredient selected from the group consisting of isoxazolines, meta-diamides, arylpyrazolheteroarylamides and arylpyrazolarylamides, wherein the at least one insecticidal active ingredient is distributed in b) a matrix material, wherein the insecticidal active ingredient—matrix material particle does not exhibit a melting peak of the active ingredient when measured in a second heating cycle after heating to a temperature of at least 20° C. above the melting point of the at least one insecticidal active ingredient at a steady heating rate using Differential Scanning Calorimetry.

3. The insecticidal active ingredient—matrix material particles according to claim 2, wherein in the first heating cycle of a Differential Scanning Calorimetry the at least one insecticidal active ingredient and the matrix material are heated to a temperature of at least 20° C. above the melting point of the at least one insecticidal active ingredient at a steady heating rate.

4. The insecticidal active ingredient—matrix material particles according to claim 3, wherein the maximal heating temperature of the first heating cycle is retained for a period of at least 10 minutes.

5. The insecticidal active ingredient—matrix material particles according to claim 3, wherein the at least one insecticidal active ingredient and the matrix material are cooled down to a temperature of between 0° C. to 40° C. between the first and second heating cycle at a steady cooling rate.

6. The insecticidal active ingredient—matrix material particles according to claim 1, wherein the weight ratio between the at least one insecticidal active ingredient and the matrix material is from 1:99 to 1:1.

7. The insecticidal active ingredient—matrix material particles according to claim1, wherein the at least one insecticidal active ingredient selected from the group consisting of 2-chloro-N-cyclopropyl-5-{1-[2,6-dichloro-4-(1,1,1,2,3,3,3-heptafluoropropan-2-yl)phenyl]-1H-pyrazol-4-yl}-N-methylnicotinamide, Broflanilide and 4-[(5S)-5-(3,5-dichloro-4-fluorophenyl)-5-(trifluoromethyl)-4,5-dihydro-1,2-oxazol-3-yl]-N-[(4R)-2-ethyl-3-oxo-1,2-oxazolidin-4-yl]-2-methylbenzamide.

8. An insecticidal composition, wherein the insecticidal composition comprises a) insecticidal active ingredient—matrix material particles according to claim 1, b) one or more surfactant(s), c) optionally further adjuvants selected from the group of anti-freeze agents, anti-foam agents, preservatives, anti-oxidants, thickeners and colourants, and d) a liquid phase.

9. The insecticidal composition according to claim 8, wherein the insecticidal composition comprises a) from 1 to 70% by weight of insecticidal active ingredient—matrix material particles according to claim 1, b) from 1 to 25% of one or more surfactant(s), c) from 0 to 25% by weight of adjuvants selected from the group of anti-freeze agents, anti-foam agents, preservatives, anti-oxidants, thickeners and colourants, and d) a liquid phase,. which i y adds up to 100% per weight of the total insecticidal composition.

10. The insecticidal composition according to claim 8 wherein the insecticidal composition is in the form of a suspension concentrate (SC) or a spray solution thereof.

11. (canceled)

12. A method for controlling pests, comprising applying insecticidal active ingredient—matrix material particles according to claim 1.

13. A method to identify a useful matrix material for an insecticidal composition with Differential Scanning Calorimetry comprising: a) heating at least one insecticidal active ingredient selected from the group consisting of isoxazolines, meta-diamides, arylpyrazolheteroarylamides and arylpyrazolarylamides and a matrix material to be tested to a temperature of at least 20° C. above the melting point of the at least one insecticidal active ingredient at a steady heating rate in a first heating cycle of the Differential Scanning Calorimetry, b) retaining the maximal heating temperature of the first heating cycle for a period of at least 10 minutes, c) cooling the temperature is down to a temperature of between 0° C. to 40° C., d) in a second heating cycle step, raising the temperature to a temperature of at least 20° C. above the melting point of the at least one insecticidal active ingredient at a steady heating rate, and e) identifying a useful matrix material in the case that the insecticidal active ingredient matrix material combination does not exhibit a melting peak when measured in the second heating cycle of the Differential Scanning Calorimetry.

14. A method for increasing the contact efficacy of an insecticidal active ingredient selected from the group consisting of isoxazolines, meta-diamides, arylpyrazolheteroarylamides and arylpyrazolarylamides with an insecticidal composition according to claim 10, in comparison to a conventional suspension concentrate formulation with the same insecticidal active ingredient.

15. A method for controlling pests, comprising applying an insecticidal composition according to claim 8.

Description

EXAMPLES

1. Representative Physicochemical Parameters of Insecticidal Active Ingredients as Used According to the Invention

[0120]

TABLE-US-00001 TABLE 1 Insecticidal Active Ingredient Melting point water solubility at pH 7 broflanilide 155° C. <0.01 mg/l 4-[(5S)-5-(3,5-dichloro-4- 145° C. <0.01 mg/l fluorophenyl)-5-(trifluoromethyl)-4,5- dihydro-1,2-oxazol-3-yl]-N-[(4R)-2- ethyl-3-oxo-1,2-oxazolidin-4-yl]-2- methylbenzamide 2-chloro-N-cyclopropyl-5-{1-[2,6- 173° C. <0.01 mg/l dichloro-4-(1,1,1,2,3,3,3- heptafluoropropan-2-yl)phenyl]-1H- pyrazol-4-yl}-N-methylnicotinamide

[0121] The reported melting points as shown in table 1 were determined under normal conditions (1 atmosphere) with technical grade active ingredients by differential thermal analysis using a Mettler Toledo 822 or 823 DSC instrument. The sample was heated from 25° C. up to 300° C. at a heating rate of 3 K/min in a perforated aluminum crucible. The melting point is determined by first specifying a baseline for the temperature range to be evaluated. A tangent is then drawn at the turning point of the endothermic side of the peak and its intersection with the baseline is stated as the melting point of the investigated substance.

[0122] The reported water solubilities as shown in table 1 are determined as follows: Preparation of calibration standards: A 1000 ppm solution of the analyte in acetonitrile is prepared and from this at least three calibration points are obtained by dilution with acetonitrile going down to 0.01 mg/L, if needed. Sample Preparation: Two cavities of a deepwell are filled each with about 0.6 mg of homogenized sample and 500 μL of a pH 7 phosphate buffer is added. A glass pearl is added to each cavity, the deepwell is sealed and shaken for at least 24 h at 1600 rpm at 23° C. After the shaking procedure the solution is filtered. Aliquots of the filtrates are analysed via a HPLC-MS system with DAD and MS detection. The peak areas of all selected single DAD and ion traces are taken for the calculations. The calculation is done by external calibration against the areas of the standard samples (linear regression). The mean of all calculated values gives the water solubility of the active ingredient.

2. Determination of the Suitability of a Matrix Material for the Insecticidal Active Ingredient Under Investigation with Differential Scanning Calorimetry (DSC)

[0123] Using differential scanning calorimetry (Mettler Toledo DSC 822e or 823 DSC) some mg of matrix material and the insecticidal active ingredient under investigation are entered into a tile and closed.

[0124] The weight ratio between matrix material and insecticidal active ingredient was as follows:

TABLE-US-00002 TABLE 2 Weight Ratio (Matrix Insecticidal Active Material/Insecticidal Samples: Matrix material: Ingredient: Active Ingredient): Sample 1 Carnauba wax 2-chloro-N-cyclopropyl-5-{1- 90:10 (Mosselmann) [2,6-dichloro-4-(1,1,1,2,3,3,3- heptafluoropropan-2- yl)phenyl]-1H-pyrazol-4-yl}- N-methylnicotinamide Sample 2 Carnauba wax Broflanilide 90:10 (Mosselmann) Sample 3 Carnauba wax 4-[(5S)-5-(3,5-dichloro-4- 90:10 (Mosselmann) fluorophenyl)-5- (trifluoromethyl)-4,5- dihydro-1,2-oxazol-3-yl]-N- [(4R)-2-ethyl-3-oxo-1,2- oxazolidin-4-yl]-2- methylbenzamide Sample 4 Licowax 371 FP (from 2-chloro-N-cyclopropyl-5-{1- 90:10 (control) Clariant) [2,6-dichloro-4-(1,1,1,2,3,3,3- heptafluoropropan-2- yl)phenyl]-1H-pyrazol-4-yl}- N-methylnicotinamide

[0125] As reference an empty closed tile was used. After equilibrating in the machine, both tiles are heated according to the following program: [0126] Heating from 25° C. to 130° C. at a heating rate of 10° C./min. [0127] Waiting for 20 min [0128] Cooling down to 25° C. at a cooling rate of 10° C./min [0129] Heating from 25° C. to 200° C. at a heating rate of 10° C./min [0130] Cooling down to 25° C. at a cooling rate of 10° C./min

[0131] In case the weight ratio between the matrix material and insecticidal active ingredient is not optimal and e.g. too much insecticidal active ingredient is present which cannot be evently distributed within the matrix material within the given time using the program above. The content of the insecticidal active ingredient can be decreased and the program can be run again or maximal heating temperature can be kept for a longer time period or alternatively, the following program can be applied: [0132] Heating from 25° C. to 200° C. at a heating rate of 10° C./min (the upper temperature can be varied, depending on the melting point of the insecticidal active ingredient to be investigated and should be 20° C. above this melting point) [0133] Waiting for 20 min [0134] Cooling down to 25° C. at a heating rate of 10° C./min [0135] Heating from 25° C. to 200° C. at a heating rate of 10° C./min (the upper temperature can be varied, depending on the melting point of the insecticidal active ingredient to be investigated and should be 20° C. above this melting point) [0136] Cooling down to 25° C. at a heating rate of 10° C./min

[0137] Results: For samples 1 to 3 no melting peak of the insecticidal active ingredient during the second heating cycle has been identified in the DSC indicating that the matrix material is suitable for the insecticidal active ingredient investigated. For sample 4 a melting peak of the insecticidal active ingredient during the second heating cycle has been identified in the DSC indicating that the matrix material is not suitable for the insecticidal active ingredient investigated.

[0138] In analogy to the above described procedure and program other matrix material—insecticidal active ingredient combinations have been investigated with insecticidal active ingredients and matrix materials have been identified which did not show a melting peak of the insecticidal active ingredient during the second heating cycle in the DSC as follows:

[0139] Insecticidal Active Ingriedient: 2-chloro-N-cyclopropyl-5-{1-[2,6-dichloro-4-(1,1,1,2,3,3,3-heptafluoropropan-2-yl)phenyl]-1H-pyrazol-4-yl}-N-methylnicotinamide in combination with one of following matrix materials: Licowax S or Licowax KSL (from Clariant).

3. Preparation of Insecticidal Active Ingredient—Matrix Particles

[0140] 30.0 gram of 2-chloro-N-cyclopropyl-5-{1-[2,6-dichloro-4-(1,1,1,2,3,3,3-heptafluoropropan-2-yl)phenyl]-1H-pyrazol-4-yl}-N-methylnicotinamide was added to 70.0 gram of Carnaubawax (Mosselmann) This mixture was stirred and heated to a temperature of 130° C. The temperature was kept while stirring until the active ingredient was evenly distributed. Subsequently the mixture was cooled down to room temperature.

[0141] The obtained matrix active ingredient composition was milled using a mixer with a cutting device (food processor Braun Küchenmaschine 3210).

[0142] In analogy to this method the same (or other) insecticidal active ingredient—matrix particles can be made (also with other concentrations).

4. Preparation of a Suspension Concentrate (SC) Formulation Based on the Insecticidal Active Ingredient—Matrix Particles as Prepared in Example 3.

[0143] For the preparation of a SC 90, 300 gram of the insecticidal active ingredient—matrix particles according to example 3 was mixed with 30.0 gram wax emulsifier 4106 (from Clariant), 5 gram aerosil 200 (Evonik), 0.4 gram Proxel GXL 20 (Lonza), and 1 gram Silcolapse 426 R (Solvay), and the mixture is then stirred until a homogeneous suspension is formed. The homogeneous suspension is subjected initially to coarse grinding and then to fine grinding, resulting in a suspension in which 90% of the solids particles have a particle size below 10 μm. Subsequently, 4 gram Kelzan (CP Kelco) and 659.6 gram of demineralized water were added at room temperature with stirring. This gives a homogeneous suspension concentrate.

5. Preparation of Conventional SC Formulations

[0144] In order to compare the characterisics of the formulations according to the invention with conventional formulations following conventional SC formulation have been prepared: SC formulation with Deltamethrin (SC200), SC formulation (SC25, SC100) with 2-chloro-N-cyclopropyl-5-{1-[2,6-dichloro-4-(1,1,1,2,3,3,3-heptafluoropropan-2-yl)phenyl]-1H-pyrazol-4-yl}-N-methylnicotinamide and an SC wax formulation (SC2.5%) with Deltamethrin.

[0145] SC formulation with Deltamethrin and the SC formulation with 2-chloro-N-cyclopropyl-5-{1-[2,6-dichloro-4-(1,1,1,2,3,3,3-heptafluoropropan-2-yl)phenyl]-1H-pyrazol-4-yl}-N-methylnicotinamide have been prepared as follows: The liquid ingredients as shown in table 3 were mixed and then solids were added and the mixture is then stirred until a homogeneous suspension is formed. The homogeneous suspension is subjected initially to coarse grinding and then to fine grinding, resulting in a suspension in which 90% of the solids particles have a particle size below 10 μm. Subsequently, Kelzan and water are added at room temperature with stirring. This gives a homogeneous suspension concentrate.

TABLE-US-00003 TABLE 3 SC formulation with 2- chloro-N-cyclopropyl-5-{1- [2,6-dichloro-4-(1,1,1,2,3,3,3- heptafluoropropan-2- yl)phenyl]-1H-pyrazol-4-yl}- SC formulation with N-methylnicotinamide (in % Deltamethrin (in % by by weight) weight) Ingredients Formulation: SC 25 Formulation: SC 200 2-chloro-N-cyclopropyl-5-{1- 2.5 [2,6-dichloro-4-(1,1,1,2,3,3,3- heptafluoropropan-2- yl)phenyl]-1H-pyrazol-4-yl}- N-methylnicotinamide Deltamethrin 18.35 Atlox 4913 (from Croda) 3.0 4.5 Soprophor TS 54 (from 5.0 1.5 Solvay) Synperonic PE/F 127 (from 5.0 Croda) Glycerin 10.0 1,2-propylene glycol 10.0 Silcolapse 426 R (from 0.1 0.275 Solvay) Proxel ® GXL 20 (Lonza 0.12 0.12 group) Preventol ® D7 (from Lanxess) 0.08 Kelzan (CP Kelco) 0.4 0.24 Citric acid 0.018 Demineralized water 73.88 64.917

[0146] The SC wax formulation (SC 2.5%) with Deltamethrin was prepared according to example 1 according to WO2016/001285A1.

6. Comparison of the Biological Contact Efficacy A gainst Mosquitos with an Inventive SC Formulation and a Conventional SC Formulation

[0147] Diluted spray solution was prepared by dissolving a specific amount of formulation in tap water.

[0148] The SC 90 formulation as prepared according to example 4 containing 9 g active ingredient per 100 g formulation was used. An appropriate amount of SC 90 formulation was dissolved in an appropriate amount of tap water and transferred to a spray robot that is capable of spraying a volume of 35 ml evenly to an area of one square meter. An active ingredient/m.sup.2 (abbreviated a.i./m.sup.2) surface concentration of 4 mg has been targeted and achieved. The sprayed surface were glazed tiles.

[0149] In addition, an appropriate amound of a conventional SC 25 formulation as prepared according to example 5 (25g active ingredient per liter) was added to an appropriate amount of tap water. 35 ml of that solution was sprayed with a spray robot onto 1 square meter in order to achieve a deposit of 4 mg active ingredient/m.sup.2. The surfaces were glazed tiles.

[0150] Control: As negative control 50 ml pure tap water were transferred to the spray robot. 35 ml of the tap water were sprayed to an area of 1 square meter. The surfaces sprayed were glazed tiles.

[0151] Then, Anopheles funestus (Malaria mosquito) insects were placed onto the dried surface of the glazed tiles for 30 min after a 24 h drying period. Afterwards, test insect were removed from the surface and transferred to clean containers for further observation. Read-out times for insects were 24 hour after contact to the treated surface. Mortality in percent (%) was measured. In the examples, 100% mortality means that all test insects were dead, whereas 0% means that no mortality could be observed. The results are shown in table 4.

TABLE-US-00004 TABLE 4 Test insects: Anopheles funestus (Malaria mosquito) Mortality [%] Formulation mg a.i./m.sup.2 24 h SC 90 (example 4) 4 100 SC 25 (example 5) 4 25 Control 0

[0152] The SC formulation according to the invention (SC 90) shows better biological contact efficacy against mosquitos in comparison to a conventional SC formulation (SC 25) with the same active ingredient at the same surface concentration.

7. Biological Performance of Known SC Formulations with Deltamethrin and “Controlled Release” Formulations with Deltamethrin in Contact Bioassay Against Mosquitos.

[0153] Similarly as outlined in example 6 a contact bioassay was conducted with the “controlled release” Deltamethrin SC 2.5 wax formulation and the conventional SC 200 formulation both prepared as described in example 5. The results are shown in table 5 (The control was the same as in example 6).

TABLE-US-00005 TABLE 5 Test insects: Anopheles funestus (Malaria mosquito) Mortality [%] Formulation mg a.i./m.sup.2 24 h Deltamethrin SC 2.5 (example 5) 4 75 Deltamethrin SC 200 (example 5) 4 85

[0154] The results in table 5 show that “controlled release” formulations—in general—are not suitable to achieve optimal results in regard to contact and initial biological efficacy.