Method for modulating the release rate of microencapsulated active ingredients

Abstract

A method for modulating the release rate of microencapsulated active ingredients comprising the following steps: I) preparation of an aqueous suspension A) comprising microcapsules of at least one active ingredient, II) preparation of a liquid emulsifiable in water, component B), comprising a solvent of the active ingredient and at least a surfactant, III) water, component C), for diluting to the application dose the active ingredient, and mixing A), B) and C).

Claims

1. A method for increasing the release rate of microencapsulated active ingredients (a.i.) in agricultural application, comprising the following steps: I) preparation of an aqueous suspension A) comprising microcapsules of an active ingredient to improve their biological efficacy, wherein the active ingredient is at least one crop protection product selected from the group consisting of an herbicide, acaricide, insecticide, a fungicide, biocide, a plant and an insect growth regulator, and antidote; II) preparation of a water-emulsifiable liquid, component B), consisting of 90% w/w of a solvent of the microencapusulated active ingredient the solvent being inert with respect to the capsule shells and substantially immiscible with water, and 10% w/w of a 1:1 mixture of nonionic and anionic surfactants, wherein the solvent is at least one selected from the group consisting of: C.sub.9-C.sub.20 alkylbenzenes, wherein the alkyl is linear or branched; C.sub.1-C.sub.4 alkyl esters of C.sub.3-C.sub.14 dicarboxylic acids, or their mixtures; C.sub.3-C.sub.10 alkyl esters of C.sub.3-C.sub.10carboxylic acids or hydroxyacids; methyl esters of C.sub.12-C.sub.22 saturated or unsaturated fatty acids or their mixtures; and III) providing water, component C), for diluting the active ingredient, and IV) mixing A), B) and C) and adjusting the ratio (by weight3 of the solvent in component B) over the active ingredient in component A to modify a release rate of the active ingredient by further adding component B), wherein by increasing the ratio by weight of the solvent of component B)/active ingredient of component A), the release rate of the active ingredient is increased, wherein the ratio by weight between the solvent of component B) and the active ingredient of component A) is between 0.5:1 and 40:1, wherein non-ionic surfactants are at least one selected from the group consisting of ethoxylated alkylarylphenols, ethoxylated fatty alcohols, ethoxylated castor oil, and ethoxylated sorbitan oleate, wherein the ethoxylated units are in the range 1-60, and wherein the anionic surfactants are selected from sulphonates and sulphosuccinates.

2. The method according to claim 1, wherein A) is added to B), or B) is added to A), and then the water of step III) is added.

3. The method according to claim 1, wherein the water of step III) is added to component A) alone and/or to component B) alone before obtaining the mixing of the three components.

4. The method according to claim 1, wherein the A)+B) is in the form of an aqueous suspo-emulsion, aqueous suspo-dispersion or aqueous suspo-microemulsion.

5. The method according to claim 1, wherein in step II) the component B) is in the form of an aqueous emulsion.

6. The method according to claim 1, wherein the solvent of the component B) shows an agrochemical activity lower than 70% on target species.

7. The method according to claim 1, wherein the suspension A) has an active ingredient concentration from 1% up to 60% w/w.

8. The method according to claim 1, wherein the microcapsules of suspensions A) has a shell of a polymeric membrane insoluble in water formed of polymers obtained by polycondensation and selected from the group consisting of polyam ides, polyesters, polyurethanes, and polyureas.

9. The method according to claim 1, wherein the herbicide is at least one selected from the group consisting of dinitroanilines, chloroacetamides, carbamates and diphenylethers.

10. The method according to claim 1, wherein the acaricide is selected from the METI class.

11. The method according to claim 1, wherein the insecticide is at least one selected from the group consisting of a pyrethroid, neonicotinoid, carbamate and an organophosphate.

12. The method according to claim 1, wherein the fungicide is at least one selected from the group consisting of an imidazole, a triazole and an anilinopyrimidine.

13. The method according to claim 1, wherein the active ingredient in the microcapsule is in admixture with other active ingredients of the same class or of different classes.

14. The method according to claim 1, wherein the microcapsules comprise solvents and activity modifiers.

15. The method according to claim 1, wherein the suspension A) comprises at least one other component selected from the group consisting of a dispersant, an excipient as a thickener, an antifoam, antifreeze, antimould agents, and activity modifiers.

16. A method according to claim 14, wherein the activity modifier is at least one selected from the group consisting of: “safener”, in case of herbicides; PBO as a synergizing agent of the active ingredient in case of insecticides and fungicides, or in case of herbicides; and a sexual pheromone, a cairomone, in case of insecticides.

17. The method according to claim 1, wherein the anionic surfactants are selected from dodecylbenzene sulphonates.

18. The method according to claim 8, wherein the polymeric membrane is formed of polyurea.

19. The method according to claim 9, wherein the herbicide is at least one selected from the group consisting of pendimethalin, trifluralin, alachlor, acetochlor, dimethenamide, metolachlor, pethoxamide, pretilachlor, molinate, triallate, EPTC, oxyfluorfen, flurochloridone, chlomazone, and dichlobenil.

20. The method according to claim 9, wherein the herbicide is oxyfluorfen.

21. The method according to claim 10, wherein the acaricide is selected from fenazaquin or pyridaben.

22. The method according to claim 11, wherein the insecticide is at least one selected from the group consisting of bifenthrin, α-cypermethrin, cypermethrin, deltamethrin, imiprothrin, γ-cyhalothrin, prallethrin, tetramethrin; phosmet, chlorpyriphos, naled, fenitrothion; imidachloprid; carbosulfan, pirimicarb, aldicarb, thiodicarb, carbofuran and propoxur.

23. The method according to claim 22, wherein the insecticide is at least one selected from the group consisting of bifenthrin α-cypermethrin, deltamethrin and γ-cyhalothrin.

24. The method according to claim 12, wherein the fungicide is at least one selected from the group consisting of imazalil, tetraconazole, tebuconazole, propiconazole and pyrimethanil.

25. The method according to claim 1, wherein the solvent comprises C.sub.10-C.sub.16 alkylbenzenes.

26. A composition for increasing the release rate of microencapsulated active ingredients (a.i.) in agricultural applications, the composition comprising a mixture of: I) an aqueous suspension A) comprising microcapsules of an active ingredient to improve their biological efficacy, wherein the active ingredient is at least one crop protection product selected from the group consisting of an herbicide, acaricide, insecticide, a fungicide, biocide, a plant and an insect growth regulator, and antidote; II) a water-emulsifiable liquid, component B), consisting of 90% w/w of a solvent of the microencapusulated active ingredient the solvent being inert with respect to the capsule shells and substantially immiscible with water, and 10% w/w of a 1:1 mixture of nonionic and anionic surfactants, wherein the solvent is at least one selected from the group consisting of: C.sub.9-C.sub.20 alkylbenzenes and their mixtures, wherein the alkyl is linear or branched; C.sub.1-C.sub.4 alkyl esters of C.sub.3-C.sub.14 dicarboxylic acids, or their mixtures; C.sub.3-C.sub.10 alkyl esters of C.sub.3-C.sub.10 carboxylic acids or hydroxyacids; methyl esters of C.sub.12-C.sub.22 saturated or unsaturated fatty acids or their mixtures; and III) water, component C), for diluting the active ingredient, and wherein a ratio by weight of the solvent in component B) over the active ingredient in component A is adjusted to modify a release rate of the active ingredient by further adding component B), wherein by increasing the ratio by weight of the solvent of component B)/active ingredient of component A), the release rate of the active ingredient is increased, wherein the ratio by weight between the solvent of component B) and the active ingredient of component A) is between 0.5:1 and 40:1, wherein component B) optionally contains at least one activity modifiers selected from the group consisting of: safeners (antidotes) in case of herbicides; PBO as synergizing agent in case of insecticides, fungicides and herbicides; and sexual pherormones, cairomones, in case of insecticides; wherein the non-ionic surfactants are at least one selected from the group consisting of ethoxylated alkylarylphenols, ethoxylated fatty alcohols, ethoxylated castor oil, and ethoxylated sorbitan oleate, wherein the ethoxylated units are in the range 1-60; and wherein the anionic surfactants are selected from sulphonates and sulphosuccinates.

27. A process for preparing the compositions of claim 26 comprising: separatedly adding B) and A) to C), while maintaining C) under stirring until reaching an active ingredient concentration corresponding to an agronomically effective rate; or adding B) to A), or adding A) to B), to obtain an undiluted mixture of A) and B), and diluting the undiluted mixture of A) and B) with C) until reaching an application rate of the active ingredient.

28. A composition for increasing the release rate of microencapsulated active ingredients (a.i.) in agricultural applications, the composition comprising a mixture of: I) an aqueous suspension A) comprising microcapsules of an active ingredient to improve their biological efficacy, wherein the active ingredient is at least one crop protection product selected from the group consisting of an herbicide, acaricide, insecticide, a fungicide, biocide, a plant and an insect growth regulator, and antidote; II) a water-emulsifiable liquid, component B), consisting of 90% w/w of a solvent of the microencapusulated active ingredient the solvent being inert with respect to the capsule shells and substantially immiscible with water, and 10% w/w of a 1:1 mixture of nonionic and anionic surfactants, wherein the solvent is at least one selected from the group consisting of: C.sub.9-C.sub.20 alkylbenzenes and their mixtures, wherein the alkyl is linear or branched; C.sub.1-C.sub.4 alkyl esters of C.sub.3-C.sub.14 dicarboxylic acids, or their mixtures; C.sub.3-C.sub.10 alkyl esters of C.sub.3-C.sub.10 carboxylic acids or hydroxyacids; methyl esters of C.sub.12-C.sub.22 saturated or unsaturated fatty acids or their mixtures; and wherein a ratio by weight of the solvent in component B) over the active ingredient in component A is adjusted to modify a release rate of the active ingredient by further adding component B), wherein by increasing the ratio by weight of the solvent of component B)/active ingredient of component A), the release rate of the active ingredient is increased, wherein the ratio by weight between the solvent of component B) and the active ingredient of component A) is between 0.5:1 and 40:1, wherein component B) optionally contains at least one activity modifiers selected from the group consisting of: safeners (antidotes) in case of herbicides; PBO as synergizing agent in case of insecticides, fungicides and herbicides; and sexual pherormones, cairomones, in case of insecticides; wherein non-ionic surfactants are at least one selected from the group consisting of ethoxylated alkylarylphenols, ethoxylated fatty alcohols, ethoxylated castor oil, and ethoxylated sorbitan oleate, wherein the ethoxylated units are in the range 1-60; and wherein the anionic surfactants are selected from sulphonates and sulphosuccinates.

29. A composition according to claim 28 comprising: A) a suspension of polyurea microcapsules comprising an herbicide, B) a mixture containing C.sub.9-C.sub.20 alkylbenzenes and their mixtures and non-ionic and anionic surfactants; wherein the ratio by weight between the solvent of B) and the active ingredient of A) is between 0.1:1 and 1:1.

30. The composition according to claim 29, wherein the composition is diluted to obtain an application rate of the active ingredient.

31. The composition according to claim 29, wherein the herbicide is oxyfluorfen.

32. The composition according to claim 29, wherein the ratio by weight between the solvent of B) and the active ingredient of A) is 0.8:1.

33. The composition according to claim 29, wherein the insecticide is γ-cyhalothrin.

34. The composition according to claim 29, wherein the ratio between the solvent(s) of B) and the active ingredient of A) is between 0.5:1 and 4:1.

35. The composition according to claim 29, wherein the ratio between the solvent(s) of B) and the active ingredient of A) is between 0.8:1 and 2:1.

Description

EXAMPLES

(1) Characterization

(2) Method for the Analytical Kinetic Determination of the Active Ingredient Release from the Microcapsules

(3) The method consists in placing a known amount of a formulation, previously diluted in water up to the application dose, on Teflon sheets and in the measurement of the active ingredient outside the microcapsule, at prefixed time (1, 2, 4, 6, 18, 24 hours) by extracting at each time the active ingredient released from the capsules with a suitable extraction solvent such as, for example, n-hexane.

(4) The procedure followed for the polyurea capsules was the following. 1) The formulation obtained according to the procedure described in the examples is diluted in distilled water until obtaining a suspension containing from 5 to 100 g of a.i./1,000 I of water (preferably 10-20 g/1,000 I). 2) 1 ml of the diluted suspension prepared in 1) is placed on a Teflon sheet having 6.5×5×0.02 cm sizes. 3) At fixed times, the Teflon sheet is transferred inside a 300 ml flask together with 50 ml of a solvent able to solubilize the a.i., but which does not affect the stability of the polymeric microcapsules. The solvent is reported in the examples. 4) The active principle released from the capsules is then extracted by shaker stirring for 5 minutes. 5) The organic solution is filtered on 0.45 μm filter, 6) The a.i. % in the extraction solvent is determined by the analytical method reported in the examples.

(5) The procedure is repeated at different times, for example, 1, 2, 4, 6, 18 and 24 hours, by using a new Teflon sheet each time. On the basis of the analytical results, the release kinetics are drawn up, by reporting the relative % of the a.i. released from the capsule with the time. As relative % it is meant the amount of a.i. released from the capsule, related to the initial concentration of the same in the starting formulation. The relative % can be calculated according to the following formula:
% rel=C/C.sub.F×100
wherein: C=a.i. concentration released from the capsules, as determined at point 6); C.sub.F=concentration of microencapsulated a.i. in the formulation.
Formulation Stability at the Dilution

(6) The stability at the dilution is evaluated by suspensibility measurements (sedimentation) determined through the method CIPAC MT 161. The greater the suspensibility (<sedimentation), the higher the composition stability.

(7) Accelerated Stability Test of the Suspension

(8) This test is used for evaluating the behaviour of the suspensions at room temperature (25° C.) for times over 1 year. It is assumed that 1 day at 54° C. corresponds to 1 month at room temperature.

(9) According to the standard test CIPAC MT 46, after 14 days of formulation storage at 54° C. (ageing test) the formulation characteristics (content, encapsulation efficiency) are again measured.

(10) Bioassay Method

(11) The biological activity of the formulations is evaluated in laboratory on a suitable species of insect by using a known and largely used method, called “leaf dip bioassay method”. This is described for example by Cahill, M. et al, Bull. Entomol. Res. 85, 181-187, 1995. Cotton plants, grown without being exposed to insecticides, are cut in the form of disks having 4 cm diameter. These disks are dipped in the insecticide water solution, containing also 0.01% of Agral® (non-ionic surfactant), and then dried at room temperature. The insecticide solutions are selected and prepared to obtain a mortality range between 0 and 100%. The control leaves are dipped in a solution formed of Agral 0.01% in distilled water. Once dried, the disks are positioned on agar (0.5%) in a petri (3 cm diameter, 1.5 cm depth). About 20 adult insects are placed on the treated cotton disks and left at 25° C. for 24 hours. The live insects are counted at zero time, after 24 and 48 hours in order to verify the mortality %.

(12) Potter Precision Laboratory Spray Tower

(13) The efficacy of the formulations was also tested using a Potter Precision Laboratory Spray Tower (as described in “Laboratory apparatus for applying direct sprays and residual films”, The Annual of Applied Biology, vol. 39, No. 1, Mar. 1, 1952).

(14) Test organisms were placed in a Petri dish (10-15 adults/replicate). The spray tower was calibrated with deionised water before application by adjusting the spraying pressure, application speed and type of nozzle to provide an output 2 mg/cm.sup.2±10% (200 I/ha). The applied amount was determined by weighing glass plates as reference before and immediately after treatment. After the calibration step the Petri dishes were sprayed with deionised water (for the untreated control) and then with the test items solutions (starting from the low concentration). The sprayer equipment was rinsed several times with deionised water among the different application of the products. The condition of the test organisms were observed at different times, for example 30′, 1 h, 3 h, 24 h after treatment (AT).

Example 1

(15) Compositions Comprising Variable Release Oxyfluorfen Microcapsules

(16) Step a): Preparation of Suspension A)

(17) To 20.0 g of Solvesso® 200 (mixture of C.sub.9-C.sub.16 alkylbenzenes having a distillation range within 226-284° C.) contained in a vessel equipped with stirrer, 17.2 g of oxyfluorfen having a 97% w/w purity are added; the mixture is heated to 50° C., while maintaining it under stirring until complete homogeneization. Then, under stirring, 2.61 g of Voronate® M 220 (isocyanate MDI) are added.

(18) In the meantime 1.1 g of dispersant Borrement CA are dispersed in 44.28 g of water and the above prepared organic mixture is added thereto, by stirring through Turrax at the maximum speed, equal to 10,000 rpm, for about 2 minutes, obtaining an oil/water emulsion.

(19) Then, under stirring, by means of a blade stirrer at 800 rpm, 2.51 g of an aqueous solution containing 40% w/w of hexamethylendiamine are added.

(20) The so obtained mixture is transferred in a reactor maintained at 50° C. After few minutes the formulation is completed by addition of 4.0 g of a thickener (Rhodopol® 23 pregelled at 2.7% w/w in water and containing 1 g of Proxel® GXL as antimould agent), 0.2 g of antifoam agent Defomex® 1510 and allowed to cure for 4 hours at 50° C.

(21) Then it is cooled to room temperature and 10.0 g of calcium nitrate are added. A suspension of microcapsules having a concentration of active principle of 180 g/l is obtained. This is then subjected to the above characterization obtaining the following results:

(22) TABLE-US-00001 granulometry 50%  <5 micron 90% <20 micron
stability at the dilution

(23) suspensibility>90%

(24) The accelerated stability test of the microcapsule suspension is carried out as described in the characterization. The test confirms the chemico-physical stability of the suspension A).

(25) Step b): Preparation of Mixture A)+B)

(26) 10 parts by weight of a mixture B), formed for 90% w/w of Solvesso® 200 and for the remaining part of a mixture 1:1 w/w of Geronol® FF6 and Geronol® FF475, are added under slow stirring to 90 parts by weight of the suspension A). The weight ratio between solvent of component B) and a.i. of component A) is 0.6:1 and the a.i. concentration in the mixture A)+B) is 15% by weight.

(27) The accelerated stability test of the composition A)+B) is carried out as described in the characterization. The test confirms the chemico-physical stability of the composition A)+B).

(28) The compositions A) and A)+B) are diluted with water until obtaining an a.i. concentration equal to 1.3 g/l. By using the described procedure and n-hexane as extraction solvent, the content of a.i. released is determined by GC-ECD (electron capture detector). Repetitions are carried out after prefixed time intervals obtaining the results reported hereinafter.

(29) TABLE-US-00002 Time A) A) + B) (h) (a.i. %) (a.i. %) 1 0.34 1.22 2 0.29 2.6 4 0.36 3.9 8 0.29 5.5

(30) The comparison of the release data shows that the diluted suspension A) has a substantially constant release with the time, while the addition of solvent B) to A) allows to significantly increase the release of the active principle with the time.

Example 2

(31) Field Tests

(32) Application in post-emergency of the composition of example 1.

(33) The formulation A)+B) has been diluted with water until obtaining an application rate of 240 g of the a.i./ha. The water volume used was 350 I/ha.

(34) A single application in post-emergency has been effected by means of a knapsuck spraying PULVAL. The application has been carried out with 3 m long spraying bar equipped with 6 nozzles TJ 80015 VS which allowed to obtain an uniform distribution of the product tested.

(35) The evaluation of herbicide activity has been made on the following infesting grasses: MATRICARIA CAMOMILLA (MAT.CH); VERONICA HEDERAEFOLIA L. (VER.HE); PAPAVER RHOEAS (PAP.RH).
The herbicide activity of the formulation found on the sown ground is reported in the following table

(36) TABLE-US-00003 Infestant Activity VER. HE. 100% PAP. RH. 100% MAT. CH. 100%

(37) The results show that the diluted composition A)+B) has a very good herbicide activity (100%) in post-emergency phase on all the tested infestants even maintaining a low phytotoxicity on the target culture (barley).

Example 3

(38) Compositions Comprising Variable Release Pendimethalin Microcapsules

(39) Following the procedure as in example 1 a commercial pendimethalin microcapsules suspension A), (MOST MICRO®), with an a.i. concentration equal to 31.7% w/w is mixed with the component B) as described in example 1 in the following amounts (parts and % by weight): formulation 3A 76 parts by weight of A) 24 parts by weight of B) (a.i.=24% w/w of A)+B)) ratio by weight between the solvent of component B) and the a.i. of A) 1:1, formulation 3B 44 parts by weight of A) 56 parts by weight of B) (a.i.=14% w/w of A)+B)) ratio by weight between the solvent of component B) and the a.i. of A) 4:1.

(40) Composition A) and the compositions A)+B) are diluted with water until obtaining a pendimethalin concentration equal to 3 g/l.

(41) Following the procedure described in the characterization and by using n-hexane as extraction solvent, the content of the a.i. released at the different times is determined by GC-ECD technique.

(42) TABLE-US-00004 Ratio a.i./B) (by weight) 1:1 1:4 Time A) [A) + B)].sub.1 [A) + B)].sub.2 (h) (a.i. %) (a.i. %) (a.i. %) 1 5.4 6.2 7.1 2 6.0 7.4 8.8 8 6.2 9.0 14.8

(43) The release data show that the addition of the solvent as component B) to suspension A) allows to significantly increase the a.i. release.

Example 4

(44) Compositions Comprising Variable Release λ-Cyhalothrin Microcapsules

(45) Step a): Preparation of Suspension A)

(46) To 20.0 g of Solvesso® 200 (mixture of C.sub.9-C.sub.16 alkylbenzenes having a distillation range in the range 226-284° C.) contained in a vessel equipped with stirrer, 20.6 g of λ-cyhalothrin having a 97% purity are added; the mixture is heated to 50° C., by maintaining under stirring until complete homogeneization. Then, always under stirring, 1.42 g of Voronate® M 220 (isocyanate MDI) are added.

(47) In the meantime 1 g of calcium ligninsulphonate dispersant, Borrement CA, are dispersed in 44.11 g of water and the above prepared organic mixture is added thereto, by stirring through Turrax at the maximum speed, equal to 10,000 rpm, for about 2 minutes, obtaining an oil/water emulsion.

(48) Then, under stirring by means of a blade stirrer at 800 rpm, 1.37 g of an aqueous solution containing 40% by weight of hexamethylendiamine are added.

(49) The mixture is then transferred in a reactor maintained at 50° C. After few minutes the formulation is completed by addition of 2 g of thickener (Rhodopol® 23 pregelled at 2.7% w/w in water and containing 1 g of Proxel® GXL as antimould agent), 0.2 g of antifoam agent Defomex® 1510 and 0.3 g of Antarox® TSP/461 and allowed to mature for four hours at 50° C.

(50) After 4 hours, 9 g of calcium nitrate are added and it is cooled to room temperature.

(51) A suspension of microcapsules having an a.i. concentration equal to 200 g/l is obtained.

(52) This is then subjected to the described characterization obtaining the following results (% of the microcapsules):

(53) TABLE-US-00005 Granulometry 50%  <5 micron 90% <20 micron
Stability at the dilution

(54) Suspensibility>90%

(55) The accelerated stability test of the microcapsule suspension was then carried out as described in the characterization. The test confirms the chemico-physical stability of the suspension A).

(56) Step b): Preparation of Mixture A)+B)

(57) Formulation 4A

(58) 15 parts of a mixture B), formed for 90% by weight of Solvesso® 200 and for the remaining part of a mixture of Geronol® FF6 and Geronol® FF475 in a weight ratio 1.5:1 are added under low stirring to 75 parts by weight of the previously prepared suspension A) and then 10 parts by weight of water are added so as to obtain a composition containing 150 g/l of a.i. The weight ratio of the solvent of component B) : a.i. of component A) is 1:1.

(59) Formulation 4B

(60) Another formulation is prepared formed of 50 parts by weight of suspension A), 40 parts by weight of mixture B) and 10 parts by weight of water so as to obtain a composition containing 100 g/l of a.i. The weight ratio between the solvent of component B) : a.i. of component A) is 4:1.

(61) The accelerated stability test is carried out on the two formulations 4A and 4B as described in the characterization. The test confirms the chemico-physical stability of the formulations.

(62) The suspension A) and the two formulations 4A and 4B are then diluted with water until obtaining an a.i. concentration equal to 250 mg/l.

(63) The results of the a.i. release for the formuation 4A are reported in example 7, for formuation 4B are reported in example 8.

Example 5

(64) Compositions Comprising Variable Release λ-cyhalothrin Microcapsules

(65) Step a): Preparation of Suspension A)

(66) 20.6 g of λ-cyhalothrin having a 97% w/w purity are added to 20.0 g of Solvesso® 200 contained in a vessel equipped with a stirrer. The mixture is heated to 50° C. under stirring until complete homogeneization. Then, under stirring, 2.84 g of Voronate® M 220 (isocyanate MDI) are added.

(67) In the meantime 1 g of calcium ligninsulphonate dispersant, Borrement CA, is dispersed in 44.11 g of water and the above prepared organic mixture is added thereto, by stirring through Turrax at the maximum speed equal to 10,000 rpm for about 2 minutes, obtaining an oil/water emulsion.

(68) Then, under stirring, by means of a blade stirrer at 800 rpm, 2.73 g of an aqueous solution containing 40% w/w of hexamethylendiamine are added.

(69) The mixture is then transferred into a reactor maintained at 50° C. After few minutes the formulation is completed by addition of 2 g of thickener (Rhodopol® 23 pregelled at 2.7% w/w in water and containing 1 g of Proxel® GXL as antimould agent), 0.2 g of antifoam agent Defomex® 1510 and 0.3 g of Antarox® TSP/461 and allowed to mature for four hours at 50° C.

(70) Then 9 g of calcium nitrate are added and it is cooled to room temperature.

(71) A suspension of microcapsules having an a.i. concentration equal to 200 g/l is obtained.

(72) This is then subjected to the described characterization obtaining the following results:

(73) TABLE-US-00006 Granulometry 50%  <5 micron 90% <20 micron
Stability at the Dilution

(74) suspensibility>90%

(75) The accelerated stability test of the microcapsule suspension has been carried out as described in the characterization. The test confirms the chemico-physical stability of the suspension A).

(76) Step b): Preparation of Mixture A)+B)

(77) Formulation 5A

(78) 15 parts by weight of a mixture B), formed for 90% w/w of Solvesso® 200 and for the remaining part of a mixture of Geronol® FF6 and Geronol® FF475 in a weight ratio 1.5:1, are added under low stirring to 75 parts by weight of suspension A). Then 10 parts by weight of water are added to obtain a composition containing 150 g/l of a.i.: The weight ratio component B):a.i. is 1:1. Then the composition A) and the composition A)+B) are diluted with water until obtaining an a.i. concentration equal to 250 mg/l.

(79) By using the previously described procedure and n-hexane as extraction solvent, the content of active ingredient released at the different times is determined by GC-ECD technique:

(80) TABLE-US-00007 Time A) Formulation 5A (h) (a.i. %) (a.i. %) 2 1.35 8.6 4 1.52 11.4 6 1.5 11 8 1.5 13.5

(81) The release data show that the addition of the solvent of component B) in the form of emulsifiable liquid to suspension A) allows to significantly increase the a.i. release.

Example 6

(82) Compositions of Variable Release Microcapsules Comprising λ-cyhalothrin and Biodiesel

(83) Step a): Preparation of Suspension A)

(84) The preparation of example 5 has been repeated but by replacing Solvesso® 200 with Biodiesel.

(85) Step b): Preparation of Mixture A)+B)

(86) Formulation 6A

(87) 15 parts by weight of a mixture B), formed for 90% by weight of Biodiesel and for 10% by weight of a mixture of Geronol® TE 777 and Geronol® FF475 in a weight ratio 1:1, are added to 75 parts by weight of the previously prepared suspension A) under low stirring. Then 10 parts by weight of water are added so as to obtain a composition containing 150 g/l of a.i. The ratio solvewnt of component B)/a.i. of component A) is 1:1. Then composition A) and composition A)+B) are diluted with water until obtaining an a.i. concentration equal to 250 mg/l.

(88) By using the described procedure and n-hexane as extraction solvent, the content of a.i. released at the different times is determined by GC-ECD technique.

(89) TABLE-US-00008 Time A) Formulation 6A (h) (a.i. %) (a.i. %) 4 6.8 25 6 9.3 37 8 14.5 52

Example 7

(90) Following the procedure described in the characterization and by using n-hexane as extraction solvent, the content of a.i. released at the different times is determined by GC-ECD technique:

(91) TABLE-US-00009 Ratio a.i./B) (by weight) 1:1 Time A) Formulation 4A (h) (a.i. %) (a.i. %) 2 20.4 23.5 4 26.8 51.4 6 27.8 70.8

(92) The release data show that the addition of the solvent of component B) in the form of emulsifiable liquid to suspension A) allows to significantly increase the a.i. release.

Example 8

(93) Following the procedure described in the characterization and by using n-hexane as extraction solvent, the content of active ingredient released at the different times is determined by GC-ECD technique:

(94) TABLE-US-00010 Ratio a.i./B) (by weight) 1:1 1:4 Time A) Formulation 4A Formulation 4B (h) (a.i. %) (a.i. %) (a.i. %) 2 20.4 23.5 35.5 4 26.8 51.4 82.1 6 27.8 70.8 85.4

(95) The release data show that the addition of the solvent of component B) in the form of emulsifiable liquid to suspension A) allows to significantly increase the a.i. release. Furthermore, as the ratio solvent of component B)/a.i. of component A) rises, the a.i. release increases.

Example 9

(96) Compositions Comprising Variable Release Microcapsules of α-cypermethrin

(97) Step a): Preparation of Suspension A)

(98) The procedure described in example 1 is repeated but using the following compounds in the amounts specified:

(99) TABLE-US-00011 α-cypermethrin (98% w/w) 10.2 g Purasolv ® EHL 26.0 g Voronate ® 2.58 g HMDA at 40% w/w 2.48 g Borrement ® CA  1.1 g Calcium nitrate 10.0 g Water 44.04 g 

(100) Microcapsules are obtained having an a.i. content of 10% w/w.

(101) Then suspension A) of microcapsules containing 5% w/w of α-cypermethrin is prepared by using the following compounds (% w/w):

(102) TABLE-US-00012 formulation of microcapsules 50 Defomex ® 1510 0.2 Rhodopol ® 23 (pregel at 2.7% w/w) 6 Water 43.8
Step b): Preparation of Mixture A)+B)
Formulation 9A

(103) 56.6 parts by weight of component B), constituted by a mixture of 80% w/w of 2-ethyihexyl lactate (Purasolv® EHL) and of 20% w/w of a mixture 4:1 (w/w) of Geronol® FF6 and Geronol® FF475, are added to 44.4 parts by weight of suspension A) of step a). The a.i. content in the mixture A)+B) is 2.2% w/w and the weight ratio between solvent of component B) and a.i. of component A) is 20:1.

(104) Composition A) and the mixture A)+B) are then diluted with water until obtaining an a.i. concentration equal to 20 mg/l.

(105) By using the described procedure and n-hexane as extraction solvent for the a.i., the content of a.i. released at the different times is determined by GC-ECD technique:

(106) TABLE-US-00013 Time A) Formulation 9A (h) (a.i. %) (a.i. %) 24 44 85

(107) The release data show that the addition of the solvent of component B) in the form of emulsifiable liquid to suspension A) allows to significantly increase the a.i. release.

Example 10

(108) Step b) of example 9 was repeated but using Solvesso® 200 instead of Purasolv® in the same amount and a ratio 1:1 (w/w) of Geronol® FF6 and Geronol® FF475. 52.6 parts by weight of component B) are added to 47.4 parts by weight of suspension A) of example 9.

(109) The a.i. content in the mixture A)+B) is 2.4% w/w and the weight ratio between solvent of component B) and a.i. of component A) is 20:1.

(110) Composition A) and the mixture A)+B) are then diluted with water until obtaining an a.i. concentration equal to 20 mg/l.

(111) By using the described procedure and n-hexane as extraction solvent for the a.i., the content of active ingredient released at the different times is determined by GC-ECD technique:

(112) TABLE-US-00014 Time A) A) + B) (h) (a.i. %) (a.i. %) 18 44 52 24 44 61

(113) The release data show that the addition of the solvent of component B) in the form of emulsifiable liquid to suspension A) allows to significantly increase the a.i. release.

Example 11

(114) To 45.9 parts by weight of A) of example 9 is added component B) formed of: 25.4 parts by weight of component B) of example 10, 28.7 parts by weight of component B) of example 9.

(115) The a.i. content in the mixture A)+B) is 2.3% w/w; the weight ratio between the solvent of component B) and the a.i. of component A) is 20:1.

(116) Composition A) and the mixture A)+B) are then diluted with water until obtaining an a.i. concentration equal to 20 mg/l.

(117) By using the previously described procedure and n-hexane as extraction solvent for the a.i., the content of active ingredient released at the different times is determined by GC-ECD technique:

(118) TABLE-US-00015 Time A) A) + B) (h) (a.i. %) (a.i. %) 18 44 67 24 44 70

(119) The release data show that the addition of the solvent of component B) in the form of emulsifiable liquid to suspension A) allows to significantly increase the a.i. release.

Example 12

(120) Compositions Comprising Variable Release Bifenthrin Microcapsules

(121) Step a): Preparation of Suspension A)

(122) The procedure described in example 1 was repeated but using the following compounds in the listed amounts:

(123) TABLE-US-00016 Bifenthrin (96% w/w) 15.6 g Purasolv ® EHL 15.0 g Voronate ® 2.14 g HMDA at 40% w/w 2.06 g Reax ® 88 B  1.1 g Calcium nitrate  9.0 g Water 51.9 g
An aqueous suspension is obtained having an a.i. content equal to 16% w/w.

(124) The following components are added to this formulation as reported:

(125) TABLE-US-00017 Microcapsule formulation 66.7% Defomex ® 1510 0.2% Rhodopol ® 23 (pregel at 2.7% w/w) 5% Proxel ® GXL 0.1% Water 28%
obtaining an aqueous suspension A) of microcapsules containing 10% w/w of a.i.
Step b): Preparation of Mixture A)+B)

(126) 71.4 parts by weight of component B) of example 9 are added to 28.6 parts weight of as above prepared component A). The a.i. content in the mixture A)+B) is 2.8% w/w and the weight ratio between the solvent of component B) and a.i. of component A) is 20:1.

(127) Suspension A) and the mixture A)+B) are then diluted with water up to a concentration equal to 20 mg/l.

(128) By using the previously described procedure and n-hexane as extraction solvent for the a.i., the content of the a.i. released is determined by GC-ECD technique:

(129) TABLE-US-00018 Time A) A) + B) (h) (a.i. %) (a.i %) 24 37 100

(130) The release data show that the addition of the solvent of component B) in the form of emulsifiable liquid to suspension A) allows to significantly increase the a.i. release.

Example 13

(131) Example 12 has been repeated by using 31.1 parts by weight of A) and 68.9 parts by weight of the component B) of example 1. The a.i. content in the mixture A)+B) is 3.1% w/w and the weight ratio between the solvent of component B) and a.i. of component A) is 20:1.

(132) The results of the a.i. release for this formuation are reported in example 14.

Example 14

(133) The formulation of example 13 has been characterized for the determination of the a.i. content by using the described procedure and n-hexane as extraction solvent for the a.i., by using GC-ECD technique. The results are the following:

(134) TABLE-US-00019 Time A) A) + B) (h) (a.i. %) (a.i. %) 24 37 100

(135) The release data show that the addition of the solvent of component B) in the form of emulsifiable liquid to suspension A) allows to significantly increase the a.i. release.

Example 15

(136) Compositions Comprising Variable Release λ-cyhalothrin Microcapsules

(137) Step a): Preparation of Suspension A)

(138) Example 5 is repeated by using the following ingredients and quantities:

(139) TABLE-US-00020 λ-cyhalothrin (97% w/w) 26.0 g Solvesso ® 200 15.0 g Voronate ® M220 2.87 g Borrement CA  1.0 g HMDA at 40% w/w 2.76 g Water 41.0 g

(140) The following components are added to the so obtained formulation:

(141) TABLE-US-00021 Rhodopol ® 23 (pregel at 2.7% w/w) 2 g Proxel ® GXL 1 g Defomex ® 1510 0.2%

(142) The mixture is allowed to mature for four hours at 50° C.

(143) Then 9 g of calcium nitrate are added and it is cooled to room temperature. A suspension of microcapsules having a.i. concentration equal to 250 g/l is obtained.

(144) The accelerated stability test of the microcapsule suspension has been carried out as described in the characterization. The test confirms the chemico-physical stability of the suspension A).

(145) Step b): Preparation of Composition A)+B)

(146) Component B) is a mixture formed by: 16.6% w/w Biodiesel, 2.5% w/w of a mixture constituted by Geronol® FF6 and Geronol® FF475 in a weight ratio 4:1, 5% w/w of a thickener (Rhodopol® 23 pregelled at 2.7% w/w in water and containing 1 g of Proxel® GXL as antimould agent), water for the remaining part up to 100% w/w.

(147) 60 parts by weight of component B) are added under low stirring to 40 parts by weight of the capsule suspension A) described in step a). The concentration of lambda-cyhalothrin in the so obtained composition is equal to 100 g/l and the ratio solvent Biodiesel of component B)/a.i. of component A) is equal to 1:1.

Example 16

(148) Efficacy of Insecticide Compositions

(149) The efficacy of different compositions of insecticide active ingredients (a.i.) against Aphis fabae (Af test) and Cydia pomonella (Codling moth) (Cp test) was evaluated.

(150) The following compositions were tested.

(151) Formulation 16A:

(152) a capsule suspension A) prepared according to step a) of example 15; a composition A)+B) prepared as described in step b) of example 15.
Formulation 16B: a commercial formulation A)′, namely Pyrinex containing microencapsulated Chlorpyrifos (250 g/l); a composition A)′+B) prepared by adding to the formulation A)' above component B) of step b) of example 6.
The ratio of the solvent of component B)/a.i. of component A)′ is 1:4.

(153) The compositions A), A)′, A)+B) and A)′+B) are diluted with water until obtaining an a.i. concentration equal to 250 mg/l.

(154) The protocols and results of efficacy trials are reported in example 16A for the Aphis fabae (Af test) and in example 16B for the Cydia pomonella (Cp test).

Example 16A

(155) Efficacy Trials on Aphis fabae (Af Test)

(156) The Aphis fabae Test (Af test) was performed according to the procedure described in the characterization, using a Potter Precision Laboratory Spray Tower.

(157) Table 1 reports the dosages and a.i. concentrations of the formulations used in this example 16A based on lambda-cyhalothrin.

(158) TABLE-US-00022 TABLE 1 N° N° insects/ ml g Formulations replicate replicate product/ha a.i./ha Suspension A) 3 10 50.00 5.00 Suspension A) 3 10 25.00 2.50 Suspension A) 3 10 12.50 1.25 Suspension A) 3 10 6.30 0.63 Suspension A) 3 10 3.20 0.32 Composition A) + B) 3 10 50.00 5.00 Composition A) + B) 3 10 25.00 2.50 Composition A) + B) 3 10 12.50 1.25 Composition A) + B) 3 10 6.30 0.63 Composition A) + B) 3 10 3.20 0.32 Suspension A)′ 3 10 20.00 5.00 Suspension A)′ 3 10 10.00 2.50 Suspension A)′ 3 10 5.00 1.25 Suspension A)′ 3 10 2.50 0.63 Suspension A)′ 3 10 1.25 0.32 Composition A)′ + B) 3 10 25.00 5.00 Composition A)′ + B) 3 10 12.50 2.50 Composition A)′ + B) 3 10 6.30 1.25 Composition A)′ + B) 3 10 3.20 0.63 Composition A)′ + B) 3 10 1.60 0.32 Untreated Control 3 10 0.00 0.00

(159) The results of the test (Af test) are reported in Table 3 as mortality assessment 24 hrs after treatment.

(160) In Table 3:
% Corrected Mortality=[(Mt−Mc)/(100−Mc)]×100
wherein Mt=% mortality of treated sample Mc=% mortality of untreated sample (untreated control)

(161) TABLE-US-00023 TABLE 3 % Dose g N.sup.o N.sup.o % Corrected Formulations a.i./ha Treated dead Mortality Mortality Suspension A) 2.50 30 18 60.00 55.56 Suspension A) 1.25 30 9 30.00 22.22 Suspension A) 0.63 30 9 30.00 22.22 Suspension A) 0.32 30 6 20.00 11.11 Composition A) + B) 2.50 30 21 70.00 66.67 Composition A) + B) 1.25 30 15 50.00 44.44 Composition A) + B) 0.63 30 18 60.00 55.56 Composition A) + B) 0.32 30 12 40.00 33.33 Suspension A)′ 5.00 30 6 20.00 11.11 Suspension A)′ 2.50 30 6 20.00 11.11 Suspension A)′ 1.25 30 6 20.00 11.11 Composition A)′ + B) 5.00 30 24 80.00 77.78 Composition A)′ + B) 2.50 30 12 40.00 33.33 Composition A)′ + B) 1.25 30 9 30.00 22.22 Untreated Control 0.00 30 3 10.00 Na

(162) The composition A)+B) has proved to be more effective than suspension A) alone 24 hours after treatment. Furthermore, the LD.sub.50 values were as follows: LD.sub.50 value for A) is 1.56 g a.i./ha, LD.sub.50 value for A)+B) is 0.66 g a.i./ha.

(163) The results of LD.sub.50 confirm that the composition A)+B) is much more effective than A) alone.

(164) The composition A)′+B) has proved to be more effective than the suspension A)′ alone 24 hours after treatment. Furthermore, the LD.sub.50 values were as follows: LD.sub.50 value for A)′ is >5.00 g a.i./ha, LD.sub.50 value for A)′+B) is 2.50 g a.i./ha.

(165) The results of LD.sub.50 confirm that the composition A)′+B) has a more improved insecticide activity compared to A)′ alone.

Example 16B

(166) Efficacy Trials on Cydia pomonella (Codling Moth) (Cp Test)

(167) Cydia pomonella test (Cp test) was carried out according to the following procedure. In a small chamber, with an area of 174 mm.sup.2 filled with a semi-synthetic media formed essentially by Agar and flours, were distributed the products in a water suspension (50 μl/174 mm.sup.2). Insect mortality was recorded at 24 hours after treatment (AT).

(168) The experimental test conditions were the following: temperature: 25° C.±2° C. relative humidity: 60-90% photoperiod: 16 h light and 8 darkness

(169) The dosages and a.i. concentrations of the formulations of example 16B based on Chlorpyrifos tested on Cydia pomonella (Cp test) are reported in Table 4.

(170) TABLE-US-00024 TABLE 4 N° N° mL g Formulations replicate insects/replicate product/ha a.i./ha Suspension A)′ 2 16 40.00 10.00 Suspension A)′ 2 16 20.00 5.00 Suspension A)′ 2 16 10.00 2.50 Suspension A)′ 2 16 5.00 1.25 Suspension A)′ 2 16 2.50 0.625 Suspension A)′ + B) 2 16 50.00 10.00 Suspension A)′ + B) 2 16 25.00 5.00 Suspension A)′ + B) 2 16 12.50 2.50 Suspension A)′ + B) 2 16 6.25 1.25 Suspension A)′ + B) 2 16 3.125 0.625 Untreated Control 2 32 0.00 0.00

(171) The results of the Cydia pomonella (Cp test) of example 16B are reported in Table 6 as the mortality assessment at 24 hrs after treatment.

(172) TABLE-US-00025 TABLE 6 % Dose g N.sup.o N.sup.o % Corrected Formulations a.i./ha Treated dead Mortality Mortality Suspension A)′ 10.00 32 14 43.75 41.94 Suspension A)′ 5.00 32 8 25.00 22.58 Suspension A)′ 2.50 32 2 6.25 3.23 Suspension A)′ 1.25 32 0 0.00 0.00 Suspension A)′ 0.625 32 0 0.00 0.00 Composition A)′ + B) 10.00 32 30 93.75 93.55 Composition A)′ + B) 5.00 32 26 81.25 80.65 Composition A)′ + B) 2.50 32 18 56.25 54.84 Composition A)′ + B) 1.25 32 8 25.00 22.58 Composition A)′ + B) 0.625 32 4 12.50 9.68 Untreated Control 0.00 32 2 3.125 3.125

(173) The composition A)′+B) has proved to be more effective than A)′ alone at 24 hours after treatment. Furthermore, the LD.sub.50 values were as follows: LD.sub.50 value for A)′ is 11.16 g a.i./ha; LD.sub.50 value for A)′+B) is 2.30 g a.i./ha.

(174) The results of LD.sub.50 show that the composition A)'+B) has a higher insecticide action compared to A)′ alone.

Example 17

(175) Efficacy of Herbicide Compositions

(176) The herbicide activity, tested in pre- and post-emergence, of different compositions against Rumex acetosa and Allium tuberosum has been evaluated. The following compositions were tested in order to compare their efficacy.

(177) The first composition (with its comparison) is as follows:

(178) a capsule suspension A) prepared as described in example 1, containing Oxyfluorfen (concentration of active 180 g/l); a composition A)+B) formed of the above A) plus component B) obtained in step b) of example 1. 90 parts by weight of A) The amount of B) added to A) allows to obtain an active ingredient concentration equal to 150 g/l and a weight ratio between solvent of component B)/a.i. of component A) equal to 0.6:1.
The second composition is as follows: a composition A)′+B), constituted by 76 parts of a commercial suspension A)′ of microencapsulated Pendimethalin (31.7% w/w), namely Most Micro, and 24 parts of B), as described in step b) of example 1. The weight ratio between the solvent of component B) and the active ingredient of component A) is equal to 1:1.
The third composition is as follows: a composition A)′+B)′, constituted by 44 parts of a commercial suspension A)′ as defined under the second composition and 56 parts of B), as obtained in step b) of example 1. The weight ratio between the solvent of component B) and the active ingredient of component A) is equal to 4:1.

(179) The compositions A), A)′, A)+B), A)′+B) and A)′+B)′ above were diluted with water until obtaining an a.i. concentration equal to 250 mg/l.

(180) The protocols and results of efficacy trials are reported in example 17A for the post-emergence test and in example 17B for the pre-emergence test.

Example 17A

(181) The post-emergence test was performed according to the following procedure. Plants were grown from seed to the 2 to 4 true leaf stage. Test composition is sprayed on the plants and leaf surfaces. The pots were irrigated with a water nutrient source located at the bottom of each pot. The plants will grow in non-porous plastic pots with a tray under the pot. The pots were large enough to allow normal growth and limit overlap of leaves among plants.

(182) Untreated control plants and treated plants were kept under the same environmental conditions.

(183) All spray solutions were prepared with deionised water on the same day of application.

(184) They were applied with an appropriate spraying equipment, calibrated in order to provide an output of 400 l/ha. The status of the plants was then evaluated in comparison with that of untreated control plants regarding the effects on vigour and growth at 7, 14 and 21 days after application (% mortality).

(185) The fresh shoot weight (Biomass) at 21 days after treatment was evaluated. The phytotoxicity was tested in terms of visual detrimental effects (chlorosis, necrosis, wilting leaf and stem deformations mortality).

(186) The above tests were performed in greenhouse under controlled climatic conditions as follows: temperature: 22±10° C.; photoperiod: 16 h light 8 h darkness; relative Humidity: 70±25%; light intensity: luminance of 350±50 μE/m.sup.2/s.

(187) Temperature, humidity, carbon dioxide concentration and light intensity were measured continuously with a data logger system.

(188) Table 7 reports the concentrations and formulations tested of example 17A.

(189) TABLE-US-00026 TABLE 7 N° N° g Formulations replicate plants/replicate a.i./ha Suspension A) 2 10 240 Suspension A) 2 10 120 Suspension A) 2 10 60 Composition A) + B) 2 10 240 Composition A) + B) 2 10 120 Composition A) + B) 2 10 60 Composition A)′ + B) 2 10 1095 Composition A)′ + B) 2 10 547.5 Composition A)′ + B) 2 10 273.75 Composition A)′ + B)′ 2 10 1095 Composition A)′ + B)′ 2 10 547.5 Composition A)′ + B)′ 2 10 273.75 Untreated Control 2 10 0.00
The results of the post-emergence test are reported in Tables 8 and 9. Table 8 reports the % mortality on Rumex acetosa in a post-emergence treatment by using A), A)+B), A)′+B) and A)′+B)′.

(190) TABLE-US-00027 TABLE 8 After 7 After 14 After 21 Formulation days days days Untreated 0 0 0 Suspension A) (a.i. 60 g/ha) 35 35 45 Suspension A) (a.i. 120 g/ha) 80 80 80 Suspension A) (a.i. 240 g/ha) 85 90 95 Composition A) + B) (a.i. 60 g/ha) 85 85 85 Composition A) + B) (a.i. 120 g/ha) 100 100 100 Composition A) + B) (a.i. 240 g/ha) 100 100 100 Composition A)′ + B) (a.i. 237.75 g/ha) — 0 10 Composition A)′ + B) (a.i. 547.5 g/ha) — 10 15 Composition A)′ + B) (a.i. 1095 g/ha) — 30 40 Composition A)′ + B)′ (a.i. 237.75 g/ha) — 5 15 Composition A)′ + B)′ (a.i. 547.5 g/ha) — 30 35 Composition A)′ + B)′ (a.i. 1095 g/ha) — 35 55
Table 9 reports the % mortality on Allium tuberosum in a post-emergence treatment by using A), A)+B), A)′+B) and A)′+B)′.

(191) TABLE-US-00028 TABLE 9 After 7 After 14 After 21 Formulation days days days Untreated 0  0 0 Suspension A (a.i. 60 g/ha) 0  0 0 Suspension A (a.i. 120 g/ha) 0 15 15 Suspension A (a.i. 240 g/ha) 10 10 15 Composition A) + B) (a.i. 60 g/ha) 5 10 10 Composition A) + B) (a.i. 120 g/ha) 10 20 20 Composition A) + B) (a.i. 240 g/ha) 30 30 30 Composition A)′ + B) (a.i. 237.75 g/ha) — — — Composition A)′ + B) (a.i. 547.5 g/ha) — — 10 Composition A)′ + B) (a.i. 1095 g/ha) — 10 15 Composition A)′ + B)′ (a.i. 237.75 g/ha) — — 5 Composition A)′ + B)′ (a.i. 547.5 g/ha) —  5 10 Composition A)′ + B)′ (a.i. 1095 g/ha) — 10 20

(192) The results obtained in the post-emergence test show that the composition A)+B) is more effective on Rumex acetosa and Allium tuberosum in terms of mortality than A) alone.

(193) The results obtained in the post-emergence test show that the composition A)′+B)′ (ratio solvent of component B)/a.i. of component A)=4:1) is more effective on Rumex acetosa and Allium tuberosum in terms of mortality than A)′+B) (ratio solvent of component B)/a.i. of component A)=1:1).

(194) Biomass

(195) The biomass, the measured fresh shoot weight data at 21 days after post-emergence treatment, is reported in Table 10.

(196) TABLE-US-00029 TABLE 10 Suspension A) Untreated Weight (g) Weight (g) Weight (g) Species Weight (g) 60 g/ha 120 g/ha 240 g/ha Rumex acetosa 12.66 1.00 0.67 0.53 Allium tuberosum 4.99 4.99 4.64 3.54 Composition A) + B) Untreated Weight (g) Weight (g) Weight (g) Species Weight (g) 60 g/ha 120 g/ha 240 g/ha Rumex acetosa 12.66 0.37 0 0 Allium tuberosum 4.99 4.13 3.81 2.69 Composition A)′ + B) Untreated Weight (g) Weight (g) Weight (g) Species Weight (g) 273.8 g/ha 547.5 g/ha 1095 g/ha Rumex acetosa 12.66 8.14 6.6 5.29 Allium tuberosum 4.99 5.05 4.97 4.33

(197) The results obtained in the post-emergence test show that the test composition A)′+B) is more effective on the Rumex acetosa and the Allium tuberosum in terms of biomass than A) alone.

(198) Phytotoxicity

(199) The phytotoxicity, in terms of chlorosis, necrosis and reduction growth, was observed at 7, 14 and 21 days and reported in Table 11 on Rumex acetosa in a post-emergence trearment, and in Table 12 on Allium tuberosum in a post-emergence trearment.

(200) In Tables 11 and 12 the meaning of the abbreviations are as follows:

(201) H=Growth reduction C=Chlorosis N=Necrosis no=no phytotoxicity

(202) TABLE-US-00030 TABLE 11 After 7 After 14 After 21 Formulation days days days Untreated no no no Suspension A (a.i. 60 g/ha) no N, C N, C Suspension A (a.i. 120 g/ha) N C C Suspension A (a.i. 240 g/ha) N N, C N, C Composition A) + B) (a.i. 60 g/ha) N no no Composition A) + B) (a.i. 120 g/ha) no no no Composition A) + B) (a.i. 240 g/ha) no no no Composition A)′ + B) (a.i. 237.75 g/ha) H no no Composition A)′ + B) (a.i. 547.5 g/ha) N, H H H Composition A)′ + B) (a.i. 1095 g/ha) N, C, H no no Composition A)′ + B)′ (a.i. 237.75 g/ha) no no no Composition A)′ + B)′ (a.i. 547.5 g/ha) H H H Composition A)′ + B)′ (a.i. 1095 g/ha) C, N, H C, N, H C, N, H

(203) TABLE-US-00031 TABLE 12 After 7 After 14 After 21 Formulation days days days Untreated no no no Suspension A (a.i. 60 g/ha) no no no Suspension A (a.i. 120 g/ha) no no no Suspension A (a.i. 240 g/ha) N, C, H H H Composition A) + B) (a.i. 60 g/ha) N, C N, C N, C Composition A) + B) (a.i. 120 g/ha) N, C N, C, H N, C, H Composition A) + B) (a.i. 240 g/ha) N, C, H N, C, H N, C, H Composition A)′ + B) (a.i. 237.75 g/ha) no no no Composition A)′ + B) (a.i. 547.5 g/ha) no no no Composition A)′ + B) (a.i. 1095 g/ha) no N N Composition A)′ + B)′ (a.i. 237.75 g/ha) no no no Composition A)′ + B)′ (a.i. 547.5 g/ha) C C C, H Composition A)′ + B)′ (a.i. 1095 g/ha) C C, N, H C, N, H

(204) The results reported in Tables 11 and 12 in the post-emergence test show that the compositions A)+B) is more effective on the Rumex acetosa and Allium tuberosum in terms of phytotoxicity than A) alone.

(205) The results of the composition A)′+B)′ (ratio solvent of component B)/a.i. of component A)=4:1) is more effective on Rumex acetosa and Allium tuberosum in terms of phytotoxicity than A)′+B) (ratio solvent of component B)/a.i. of component A)=1:1).

Example 17B

(206) The pre-emergence test was performed according to the following procedure. Seeds were placed in contact with soil treated with the test substance. The pots were irrigated with a water nutrient source located at the bottom of each pot. The plants will grow in non-porous plastic pots with a tray under the pot. The pots were large enough to allow normal growth and limit overlap of leaves among plants.

(207) Untreated control plants and treated plants were kept under the same environmental conditions.

(208) All spray solutions were prepared with deionised water on the day of application.

(209) Test solutions were applied by means of an appropriate spraying equipment, calibrated in order to provide an output of 400 l/ha. The measured endpoints were visual assessment of seedling emergence (% emergence), fresh shoot weight at 21 days after treatment (biomass) and visual detrimental effects evaluated as chlorosis, mortality, plant development abnormalities (phytotoxicity).

(210) The above tests were performed in greenhouse under controlled climatic conditions as follows: temperature: 22±10° C.; photoperiod: 16 h light 8 h darkness; relative Humidity: 70±25%; light intensity: luminance of 350±50 μE/m.sup.2/s.

(211) Temperature, humidity, carbon dioxide concentration and light intensity were measured continuously with a data logger system.

(212) The concentrations and formulations tested of example 17B on Rumex acetosa and Allium tuberosum are reported in Table 13.

(213) TABLE-US-00032 TABLE 13 N° N° g Formulations replicate plants/replicate a.s/ha Suspension A) 2 10 240 Suspension A) 2 10 120 Suspension A) 2 10 60 Composition A) + B) 2 10 240 Composition A) + B) 2 10 120 Composition A) + B) 2 10 60 Untreated Control 2 10 0.00

(214) The results of the pre-emergence test (indicated as % of emergence) are reported in Table 14 for Rumex acetosa and in Table 15 for Allium tuberosum.

(215) TABLE-US-00033 TABLE 14 After 7 After 14 After 21 Formulation days days days Untreated 20 35 70 Suspension A) (a.i. 60 g/ha) 20 20 20 Suspension A) (a.i. 120 g/ha) 20 20 15 Suspension A) (a.i. 240 g/ha) 10 10 0 Composition A) + B) (a.i. 60 g/ha) 20 20 7.14 Composition A) + B) (a.i. 120 g/ha) 20 15 7.5 Composition A) + B) (a.i. 240 g/ha) 10 5 0

(216) TABLE-US-00034 TABLE 15 After 7 After 14 After 21 Formulation days days days Untreated 20 40 75 Suspension A) (a.i. 60 g/ha) 30 40 40 Suspension A) (a.i. 120 g/ha) 27 35 35 Suspension A) (a.i. 240 g/ha) 25 34 25 Composition A) + B) (a.i. 60 g/ha) — 38 24 Composition A) + B) (a.i. 120 g/ha) — 32 24 Composition A) + B) (a.i. 240 g/ha) 20 20 20

(217) The results obtained in the pre-emergence test show that the composition A)+B) is more effective on the Rumex acetosa and Allium tuberosum than A) alone.

(218) Biomass

(219) The biomass, as measured fresh shoot weight data at 21 days after treatment, is reported in Table 16.

(220) TABLE-US-00035 TABLE 16 Suspension A) Untreated Weight (g) Weight (g) Weight (g) Species Weight (g) 60 g/ha 120 g/ha 240 g/ha Rumex acetosa 0.5 0.24 0.16 0 Allium tuberosum 1.28 1.07 0.99 0.82 Composition A) + B) Untreated Weight (g) Weight (g) Weight (g) Species Weight (g) 60 g/ha 120 g/ha 240 g/ha Rumex acetosa 0.5 0.17 0.09 0 Allium tuberosum 1.28 0.92 0.86 0.70

(221) The results of biomass in the pre-emergence test show that the composition A)+B) is more effective on the Rumex acetosa and Allium tuberosum than A).

(222) Phytotoxicity

(223) The phytotoxixity, evaluated as chlorosis and necrosis, observed at 14 and 21 days, is reported in Table 17 for Rumex acetosa and in Table 18 for Allium tuberosum.

(224) In the Tables

(225) H=Growth reduction C=Chlorosis N=Necrosis no=no phytotoxicity

(226) TABLE-US-00036 TABLE 17 After 14 After 21 Formulation days days Untreated no no Suspension A (a.i. 60 g/ha) no no Suspension A (a.i. 120 g/ha) N N Suspension A (a.i. 240 g/ha) N N Composition A) + B) (a.i. 60 g/ha) N N Composition A) + B) (a.i. 120 g/ha) N N Composition A) + B) (a.i. 240 g/ha) N N

(227) TABLE-US-00037 TABLE 18 After 14 After 21 Formulation days days Untreated no no Suspension A (a.i. 60 g/ha) no no Suspension A (a.i. 120 g/ha) no no Suspension A (a.i. 240 g/ha) no no Composition A) + B) (a.i. 60 g/ha) N N Composition A) + B) (a.i. 120 g/ha) C, N C, N Composition A) + B) (a.i. 240 g/ha) C, N C, N

(228) The results obtained in the pre-emergence test show that the composition A)+B) is more effective on Rumex acetosa and Allium tuberosum in terms of phytotoxicity than A) alone.

Example 18

(229) Compositions Comprising Microcapsules Containing Bifenthrin Having a Controlled Release

(230) Step a): Preparation of Suspension A)

(231) It was prepared according to step a) of example 12.

(232) Step b): Preparation of Composition A)+B)

(233) To 28.6 parts by weight of the suspension A) are added 1.5 parts by weight of the mixture B), obtained in step b) of example 9. The active ingredient content in the mixture [A)+B)]′ is 9.5% w/w and the weight ratio between solvent of component B) and the a.i. of component A) is 0.42:1.

(234) Analogously, a mixture [A)+B)]″ is prepared by adding 14.30 parts by weight of B) to 28.6 parts by weight of A). The weight ratio between the solvent of component B) and the a.i. of component A) is 4:1 and the active ingredient is 6.7% w/w.

(235) The capsules suspension A), mixtures [A)+B)]′ and [A)+B)]″ were diluted in water up to a concentration of 20 mg/l of active ingredient.

(236) By using the procedure described in the characterization and n-hexane as solvent of extraction of the a.i., the amount of a.i. released from the microcapsules is determined by means of GC-ECD.

(237) The results obtained are below reported.

(238) TABLE-US-00038 Solvent of B)/a.i — 0.42:1 4:1 Time A) [A) + B)]′ [A) + B)]″ (h) (a.i. %) (a.i. %) (a.i. %) 1 n.d. 19 36 6 n.d. 26 50 24 37 92 100 (n.d. means non detectable).

(239) The results show that [A)+B)]′ and [A)+B)]″ are more effective than A) alone.

Example 19

(240) Efficacy Trials

(241) The compositions described in example 18 were tested on a susceptible strain of, using a Potter Tower, as described in the characterization. Approximately 15 adult females of Aphis fabae were placed on a Petri dish of 6 cm diameter. The suspension of microcapsules A) and the compositions [A)+B)]′ and [A)+B)]″ were diluted in water up to an applicative dosage of 3 g a.i./ha.

(242) The treatments were performed at a pressure correspondent to 2.7 mbar using a volume of insecticide solution equal to 1.25 ml. Between each treatment and the following one, the Potter Tower was washed several times with demineralized water. The efficacy in terms of mortality of the aphids was evaluated after 1 hour, 6 hours and 24 hours.

(243) The results are reported in Table 19.

(244) TABLE-US-00039 TABLE 19 Mortality after Mortality after Mortality after 1 hr (%) 6 hrs (%) 24 hrs (%) untreated 0 0 0 A) 0 17.24 60.00 [A) + B)]′ 53.33 66.67 100.00 [A) + B)]″ 83.87 88.24 100.00

(245) The results show that the efficacy of the compositions [A)+B)]′ and [A)+B)]″ is higher than that of the capsule suspension A). In particular, it is evident that, increasing the amount of B) added to A) ([A)+B)]″ vs [A)+B)]′), the efficacy of the microencapsulated formulation is enhanced. This is in agreement with the release time evaluations reported in example 18.