Emulsifiable concentrate for a phytosanitary composition, phytosanitary composition and phytosanitary film

Abstract

An emulsifiable concentrate for emulsified phytosanitary composition, including more than 90% by weight of at least one mixture of hydrocarbons having a distillation cut greater than 250 C., less than 20% by weight of n-paraffins and less than 1% aromatics, and from 1 to 4% by weight of a mixture of at least two surfactants TA1 and TA2, such that TA2 is more hydrophobic than TA1, the HLB of the mixture of which varies from 6 to 10.

Claims

1. An emulsifiable concentrate for an emulsified phytosanitary composition, comprising: more than 90% by weight of at least one mixture of hydrocarbons having a distillation cut greater than 250 C., comprising less than 20% by weight n-paraffins and less than 1% aromatics, from 1 to 4% by weight of a mixture of at least a first surfactant (TA1) and a second surfactant (TA2), such that TA2 is more hydrophobic than TA1 for a difference in hydrophile-lipophile balance (HLB) between TA1 and TA2 varying from 3 to 11 and the HLB of the mixture of which varies from 6 to 10, wherein the first surfactant TA1 is chosen from polyalkoxylated carboxylic acids, comprising a carbon chain with 16 to 20 carbon atoms having at least one olefin bond, each polyalkoxylated group comprising from 3 to 15 alkoxylated radicals, itself comprising from 1 to 4 carbons per oxygen atom, the HLB of the TA1 varying from 5 to 16, and from 0.0001% to 1% by weight of water; wherein the hydrocarbon mixture comprises more than 50% by weight of hydrocarbons containing from 15 to 30 carbon atoms.

2. The concentrate according to claim 1, further comprising from 2 to 3% surfactant TA1, and from 0.1 to 0.9% surfactant TA2.

3. The concentrate according to claim 1, wherein the water content is comprised between 0.05 and 0.5% by weight of the concentrate.

4. The concentrate according to claim 1, wherein the surfactant TA1 is chosen from the polyethoxylated oleic acids comprising from 4 to 8 ethoxylated radicals.

5. The concentrate according to claim 1, wherein the surfactant TA2 is selected from the group consisting of: sorbitan mono- and/or polycarboxylates; ethoxylated sorbitan mono- and/or polycarboxylates; glycerol mono- and/or polycarboxylates; and ethoxylated glycerol mono- and/or polycarboxylates, each polycarboxylate group comprising 1 to 3 carbon chains of 12 to 20 carbon atoms having at least one olefin bond, the polyethoxylated group comprising 1 to 5 ethoxylated groups, the HLB of the TA2 varying from 1 to 11.

6. The concentrate according to claim 1, wherein the surfactant TA2 is a sorbitan monooleate or a glycerol monooleate or their mixture.

7. A phytosanitary emulsion comprising: a) from 0.5% by weight to 10% by weight of an emulsifiable concentrate comprising: i) more than 90% by weight of at least one mixture of hydrocarbons having a distillation cut greater than 250 C., comprising less than 20% by weight n-paraffins and less than 1% aromatics, ii) from 1 to 4% by weight of a mixture of at least a first surfactant (TA1) and a second surfactant (TA2), such that TA2 is more hydrophobic than TA1 for a difference in hydrophile-lipophile balance (HLB) between TA1 and TA2 varying from 3 to 11 and the HLB of the mixture of which varies from 6 to 10; wherein the first surfactant TA1 is chosen from polyalkoxylated carboxylic acids, comprising a carbon chain with 16 to 20 carbon atoms having at least one olefin bond, each polyalkoxylated group comprising from 3 to 15 alkoxylated radicals, itself comprising from 1 to 4 carbons per oxygen atom, and HLB of the TA1 varying from 5 to 16, and iii) from 0.0001% to 1% by weight of water; and b) from 99.5% to 90% fresh and/or salt water; c) wherein the hydrocarbon mixture comprises more than 50% by weight of hydrocarbons containing from 15 to 30 carbon atoms.

8. The emulsion according to claim 7, comprising from 0.5 to 3% by weight of the concentrate and from 97 to 99.5% fresh and/or salt water, which emulsion has a creaming time according to the procedure MT36 between 25 seconds and 2 minutes.

9. The emulsion according to claim 7, wherein the emulsion does not show any deposit after 14 days of storage at 54 C. according to a procedure recommended by CIPAC MT 46.3.1.

10. A method for producing the emulsion according to claim 7, further comprising mixing the concentrate and the water in a tank on the site of application of the emulsion and emulsifying it by a static emulsifier or a rotor stator mixer.

11. A method for the insecticidal and/or fungicidal treatment of crops comprising the step of spraying onto crops a phytosanitary emulsion comprising: a. From 0.5% by weight to 10% by weight of an emulsifiable concentrate comprising: i. more than 90% by weight of at least one mixture of hydrocarbons having a distillation cut greater than 250 C., comprising less than 20% by weight n-paraffins and less than 1% aromatics, ii. from 1 to 4% by weight of a mixture of at least a first surfactant (TA1) and a second surfactant (TA2), such that TA2 is more hydrophobic than TA1 for a difference in hydrophile-lipophile balance (HLB) between TA1 and TA2 varying from 3 to 11 and the HLB of the mixture of which varies from 6 to 10, wherein the first surfactant TA1 is chosen from polyalkoxylated carboxylic acids, comprising a carbon chain with 16 to 20 carbon atoms having at least one olefin bond, each polyalkoxylated group comprising from 3 to 15 alkoxylated radicals, itself comprising from 1 to 4 carbons per oxygen atom, the HLB of the TA1 varying from 5 to 16, and iii. from 0.0001% to 1% by weight of water; and b. from 99.5% to 90% fresh and/or salt water; c. wherein the hydrocarbon mixture comprises more than 50% by weight of hydrocarbons containing from 15 to 30 carbon atoms.

12. The method according to claim 11 wherein the phytosanitary emulsion is sprayed onto fruit tree crops.

13. The method according to claim 12, wherein the fruit tree crops comprise banana trees or lemon trees.

14. A homogeneous oil film obtained by vaporization of an emulsion comprising: a. from 0.5% by weight to 10% by weight of an emulsifiable concentrate comprising: i. more than 90% by weight of at least one mixture of hydrocarbons having a distillation cut greater than 250 C., comprising less than 20% by weight n-paraffins and less than 1% aromatics, and ii. from 1 to 4% by weight of a mixture of at least a first surfactant (TA1) and a second surfactant (TA2), such that TA2 is more hydrophobic than TA1 for a difference in hydrophile-lipophile balance (HLB) between TA1 and TA2 varying from 3 to 11 to the HLB of the mixture of which varies from 6 to 10; wherein the first surfactant TA1 is chosen from polyalkoxylated carboxylic acids, comprising a carbon chain with 16 to 20 carbon atoms having at least one olefin bond, each polyalkoxylated group comprising from 3 to 15 alkoxylated radicals, itself comprising from 1 to 4 carbons per oxygen atom, the HLB of the TA1 varying from 5 to 16, and iii. from 0.0001% to 1% by weight of water; b. from 99.5% to 90% fresh and/or salt water; c. the homogenous oil film being deposited on trunks and leaves, and comprising less than 5% water; and d. wherein the hydrocarbon mixture comprises more than 50% by weight of hydrocarbons containing from 15 to 30 carbon atoms.

15. An emulsifiable concentrate for an emulsified phytosanitary composition, comprising: more than 90% by weight of at least one mixture of hydrocarbons having a distillation cut greater than 250 C., comprising less than 20% by weight n-paraffins and less than 1% aromatics, from 1 to 4% by weight of a mixture of at least a first surfactant (TA1) and a second surfactant (TA2), such that TA2 is more hydrophobic than TA1 for a difference in hydrophile-lipophile balance (HLB) between TA1 and TA2 varying from 3 to 11 and the HLB of the mixture of which varies from 6 to 10, wherein the first surfactant TA1 is chosen from polyalkoxylated carboxylic acids, comprising a carbon chain with 16 to 20 carbon atoms having at least one olefin bond, each polyalkoxylated group comprising from 3 to 15 alkoxylated radicals, itself comprising from 1 to 4 carbons per oxygen atom, the HLB of the TA1 varying from 5 to 16, and from 0.0001% to 1% by weight of water; wherein the mixture of hydrocarbons comprises less than 10 ppm sulphur and less than 100 ppm aromatics and is chosen from the group constituted by the hydrodewaxed hydrocarbons containing more than 50% by weight isoparaffins and desulphurized and dearomatized hydrocarbons containing more than 20% by weight naphthenes of which more than 10% are polynaphthenes.

16. The concentrate according to claim 15, wherein the composition does not show any deposit after 14 days of storage at 54 C. according to a procedure recommended by CIPAC MT 46.3.1.

17. An emulsifiable concentrate for an emulsified phytosanitary composition, comprising: more than 90% by weight of at least one mixture of hydrocarbons having a distillation cut greater than 250 C., comprising less than 20% by weight n-paraffins and less than 1% aromatics, from 1 to 4% by weight of a mixture of at least a first surfactant (TA1) and a second surfactant (TA2), such that TA2 is more hydrophobic than TA1 for a difference in hydrophile-lipophile balance (HLB) between TA1 and TA2 varying from 3 to 11 and the HLB of the mixture of which varies from 6 to 10, wherein the first surfactant TA1 is chosen from polyalkoxylated carboxylic acids, comprising a carbon chain with 16 to 20 carbon atoms having at least one olefin bond, each polyalkoxylated group comprising from 3 to 15 alkoxylated radicals, itself comprising from 1 to 4 carbons per oxygen atom, the HLB of the TA1 varying from 5 to 16, and from 0.0001% to 1% by weight of water; wherein the mixture of hydrocarbons is chosen from gas oil cuts having boiling points above 250 C., originating from hydrocracking vacuum distillate gas oils or other refining processes, these cuts having been desulphurized and/or dearomatized by catalytic hydrogenation then distilled into cuts with ranges of less than 75 C., these cuts comprising more than 20% naphthenes and having a pour point below 15 C.

18. The concentrate according to claim 17, wherein the hydrocarbon mixture comprises more than 50% by weight of hydrocarbons containing from 15 to 30 carbon atoms.

19. The concentrate according to claim 17, wherein the composition does not show any deposit after 14 days of storage at 54 C. according to a procedure recommended by CIPAC MT 46.3.1.

Description

DETAILED DESCRIPTION

(1) The following examples are given for the purposes of illustration, but cannot be considered as limiting the invention.

Example 1

(2) The present example is intended to describe the preparation of emulsifiable concentrates that are composed of 3% by weight of a mixture of two surfactants TA1 and TA2, 0.1% by weight of water and of 96.9% by weight of hydrocarbons. These hydrocarbons are constituted by a dearomatized gas oil cut, the temperature of the cut being comprised between 305 and 380 C. containing 27% naphthenes and 73% paraffins, of which more than 90% by weight are isoparaffins.

(3) Several combinations of surfactants TA1 and TA2 were tested: the characteristics of these mixtures are described in Table I below. The samples of concentrates obtained are referenced Xi.

(4) TABLE-US-00001 TABLE I Surfactants HLB eq Ecotoxicity Visible Concentrates TA1 TA2 TA1 TA2 Mix TA1 TA2 deposit X1 2 OE Sorbitan 5.9 4.3 5.6 High Low No Ethoxylated monooleate C13-C15 alcohol X2 20 OE Sorbitan 8.9 4.3 7.1 Low Low No Ethoxylated monooleate Triglycerides of rapeseed X3 10 OE Sorbitan 12.0 4.3 9.4 Low Low No Ethoxylated monooleate oleic acid X4 6 OE Sorbitan 9.8 4.3 8.9 Low Low No Ethoxylated monooleate oleic acid

(5) The mixture satisfies a linear mixture law on the basis of the weight fractions of each of the surfactants: thus the average HLB is equal to xHLB(TA1)+yHLB(TA2), x and y corresponding to the weight concentrations of these TAi in the mixture.

(6) The emulsions according to the invention, prepared from concentrates Xi, satisfy certain characteristics. They do not show a deposit after storage for 14 days at 54 C. according to the procedure recommended by CIPAC MT 46.3.1, and they satisfy the creaming test described below. The creaming test is carried out according to the CIPAC MT 36 procedure. The emulsions are prepared in a graduated test tube by dispersing 5 mL of an emulsifiable concentrate in 95 mL of hard water (containing 274 ppm CaCO.sub.3 and 27 ppm MgO). The concentrate and the water are preheated to 30 C. in order to emulsify more easily, and the emulsion is formed by successively upturning the same test tube after it has been sealed. For each test tube, the creaming time is then measured, i.e. the time required to obtain 4 mL hydrocarbons. Table II shows the creaming time for each of the concentrates Xi of Table I.

(7) TABLE-US-00002 TABLE II Creaming time/4 mL Emulsion concentrate HLB eq oil (seconds) E1 X1 5.6 33 E2 X2 7.1 15 E3 X3 9.4 17 E4 X6 8.9 40

(8) If the stability of the emulsions according to the invention is compared to that of the emulsions of the prior art (here E1), it is noted that the emulsions according to the invention give a reasonable creaming time, i.e. a sufficient resistance to separation before spraying and water run-off on contact with the crops. It is noted moreover, that the presence of a deposit is prohibitive for a food quality application onto citrus fruit. In fact, the appearance of a deposit is evidence of a homogeneity deficiency of the emulsion and therefore of a product having properties that are different from those expected.

(9) Moreover, the concentrates of additives of the emulsions according to the invention, X2, X3 and X4 present the best average HLB compromise with surfactants having very different HLB values. Unlike the emulsions of the prior art, these surfactants are all ecotox.

Example III

(10) The present example aims to exemplify the fungicidal and insecticidal effects of the emulsion according to the invention. Samples of products to be tested on citrus groves (oranges) are prepared. The reference R corresponds to an untreated citrus plot.

(11) Emulsions according to the invention are used, obtained from X6, at 3% in a mixture of hydrocarbons as described in Example 1 for forming the concentrate. This concentrate is mixed at concentrations of 1 and 2% in water, then emulsified. The citrus groves are sprayed at a rate of 1200 L/ha. The efficacy of these emulsions is compared to that of an emulsion of the prior art T1, as described hereinafter and to a chemical reference product corresponding to the use of a synthetic pesticide, here Chlorpyrifos, reference T2.

(12) For the emulsion T1, the concentrate is prepared using 1.4% ethoxylated C.sub.12-C.sub.14 alcohol and 1.6% ethoxylated C.sub.13 alcohol acid phosphate in the same mixture of hydrocarbons. As previously, this concentrate is mixed at concentrations of 1 and 2% in water then emulsified. The resulting emulsions are applied in an identical manner onto citrus.

(13) The efficacy of these emulsions in preventing harmful insect activity is then evaluated, by comparison with the reference products and the prior art. To this end, a count is undertaken of the number of insects present at the time of application of the emulsions on the reference, and the number of insects having withstood the treatment after 20 days. The efficacy is measured according to the Abbott formula based on the number of live insects, the number of dead insects and the % of citrus infected (more than 3 insects per fruit).

(14) The Abbott formula is the following:
% efficacy=[(untreatedtreated)/untreated)]100
The results are given in Table III and IV below. (l/hl indicates l of concentrate per hl of water)

(15) TABLE-US-00003 TABLE III Name of Parasite Aonidiella aurantii Type of Evaluation Number of Number of Number of live live dead % fruits individuals individuals individuals % mortality infected Reference time Treatment Concentration t = 0 t + 20 days t + 20 days t + 20 days t + 20 days R 225.5 231.8 3.0 1.3 46.5 E4 1.01/hl 215.3 58.0 145.0 71.4 12.3 E4 2.01/hl 211.0 22.0 175.5 88.8 7.8 T1 1.01/hl 216.8 59.0 160.0 73.0 12.3 T1 2.01/hl 207.3 21.5 177.5 89.1 7.0 T2 0.151/hl 216.5 23.5 172.0 88.0 7.8

(16) TABLE-US-00004 TABLE IV Name of Parasite Aonidiella aurantii Type of Evaluation % Efficacy (Based on the number of % Efficacy (Based live individuals) on mortality) Reference time (days) Treatment Concentration t + 20 t + 20 E4 1.01/hl 75.0 73.7 E4 2.01/hl 90.5 83.3 T1 1.0l/hl 74.5 73.7 T1 2.01/hl 90.7 84.9 T2 0.151/hl 89.9 83.3