WO2020104475A1 - Dithiocarbamate oil dispersions - Google Patents

Abstract

Dithiocarbamate oil dispersion comprising a polyamide obtained by reacting a fatty acid, a polyamine and a di- or tri-carboxylic acid in a specific molar ratio and use thereof in agriculture.

Description

DITHIOCARBAMATE OI L DISPERSIONS

TECHNICAL FIELD

The present invention relates to a dithiocarbamate oil dispersion comprising a polyamide obtained by reacting a fatty acid and a di- or tri- carboxylic acid with a polyamine in a specific molar ratio.

This invention also pertains to the use in agriculture of the dithiocarbamate oil dispersion comprising the above mentioned polyamide.

PRIOR ART

Dithiocarbamates (DTC) are by the most important group of organic fungicides for controlling plant diseases. DTCs are characterized by a broad spectrum of activity against various plant pathogens, low acute mammal toxicity, and low production costs. Owing to their known chemical instability at elevated temperature in the presence of moisture, dithiocarbamate active substances are, as a rule, formulated as solid formulations, such as dispersible powders and granules, or as oil dispersions.

Agrochemical oil dispersions (OD) are stable suspensions of agrochemical active ingredients, such as pesticides and crop protection chemicals, in organic fluids, and are usually intended for dilution with water before use. Oil dispersions are particularly useful for formulating oil insoluble solid active ingredients and for hydrolytically unstable compounds in aqueous compositions, such as dithiocarbamates.

A disadvantage of the OD formulations, in particular of dithiocarbamates, is that such formulations are not stable for enough time and show phase separation upon storage. Thus, storage even at ambient temperatures frequently leads to aggregation effects, viscosity buildup, gel formation or pronounced settling of the suspended phase. In the worst cases, the effects are irreversible, i.e. even strong shearing, for example by stirring, cannot re-homogenize the formulation.

A common method to solve this problem is usually to add to the dispersions a stabilizer that can act as a thickener increasing the viscosity of the system and/or can act as dispersant reducing the settling rate of the particles.

Typical stabilizer for waterless organic systems include organoclays, such as Bentone®. Organoclays are made from natural smectite, hectorite or montmorillonite clays by reacting the hydrophilic clay with quaternary ammonium compounds, so that it becomes organophilic and therefore compatible with non-aqueous media.

Other known stabilizer are surfactants, vegetable oil derivatives, silica derivatives and synthetic polymers.

For example, WO 2000/072681 describes an essentially anhydrous dithiocarbamate liquid formulation comprising : at least one active ingredient from the class of the dithiocarbamates, an essentially anhydrous oil phase, a polyhydroxystearic acid or a derivative thereof and/or an alkyl or alkenyl glycerin ether ethoxylate, as stabilizers, and, optionally, an anionic surfactant.

US 2009/202648 describes a dispersion comprising : a disperse phase comprising ethylene bis(dithiocarbamate); a continuous phase comprising a water immiscible liquid; and, as stabilizer, a metal polyacrylate having a molecular weight of from about 150 to about 15,000 Daltons.

US 2011/237591 relates to fungicidal plant protection formulations comprising : a) dimethomorph and b) at least one dithiocarbamate, formulated as an oil suspension concentrate in a liquid organic diluent and in the presence of at least one surface-active substance. Silicates, modified silicates, organic thickeners, for example those based on hydrogenated fatty acids and fatty acid derivatives, and thickeners based on synthetic polymers are mentioned among the suitable stabilizers.

WO 2012/167322 relates to an agricultural oil-based suspension formulation comprising an active ingredient suspended in finely divided form in an oil; and, as stabilizer, at least one surfactant selected from a polyalkylene glycol-fatty acid condensate or a polyalkylene glycolether fatty acid condensate. Dithiocarbamates are mentioned among the active ingredients. WO 2016/153913 describes an agrochemical formulation comprising a pesticide or mixture of pesticides, among which dithiocarbamates, and an adjuvant composition comprising an oil and a maleated natural oil derivative obtained from the reaction of a maleated natural oil and a derivative compound comprising at least one polyoxyalkylene glycol, mono-alkyl polyoxyalkylene glycol, polyether amine, alkylene amine, alkanol amine, etc. Polyamines, such as ethylene diamine, diethylene tetramine, triethylene diamine and triethylene tetramine, are included among the alkyleneamines.

Unfortunately, all these stabilizers show drawbacks and problems which reduce their applicability and performances.

They do not always impart sufficient stability to the dispersions across the desired temperature range and for enough time.

Since they can sensibly increase the viscosity of the dispersion, they must be very cautiously dosed.

Organoclays have to be carefully dispersed and need the presence of a chemical activator in order to function as anti-settling agents. If the organoclay is not well dispersed or chemically activated the result is poor cohesion strength and hence limited physical stability of the product.

Furthermore, the handling of most of these stabilizer is very difficult and/or harmful because they are mainly very fine and light powders or extremely viscous liquids.

Finally, they are difficult to dissolve/homogenize in the dispersions while avoiding the formation of gels or lumps and continued and careful monitoring of the formulation process is required.

For these reasons, a need still exist of a stabilizer that improves the physical stability of oil dispersions of fungicides of the family of dithiocarbamates without showing the above mentioned problems.

We have now found that oil dispersions of dithiocarbamates can be stabilized using an oil-soluble polyamide obtained by reacting in a specific ratio a fatty acid and a polyamine and, subsequently, reacting the obtained aminoamide with a di- or tri-carboxylic acid. This polyamide facilitates the preparation of dithiocarbamate oil dispersions and their storage, even in hot climates, for their effective use in agronomic applications.

Polyamides have been already proposed as stabilizer for agrochemical oil dispersions.

WO 2012/080208 describes a method for the preparation of an agrochemical oil dispersion comprising a thickener which is an amide obtained by reacting a polyhydroxystearic acid with diethylene triamine and/or triethylene tetramine. Dithiocarbamates are mentioned among the various agrochemical compounds suitable for the preparation of the oil dispersions.

WO 2015/145105 discloses an oil dispersion comprising an oil, at least one agrochemical active and/or nutrient and a polyamide formed from a dimer acid compound, optionally a C₄-Ci₂ co-dicarboxylic acid, and one or more diamine compounds. The agrochemical active can be chosen in a very long list of pesticides, including fungicides, herbicides, insecticides, algicides, moluscicides, miticides, and rodenticides; and antimicrobials, including germicides, antibiotics, antibacterials, antivirals, antifungals, antiprotozoals and antiparasites.

As far as the Applicant knows, none of the prior art documents discloses the use of the specific polyamides of the invention as stabilizers for dithiocarbamate oil dispersions.

The expression "dithiocarbamate oil dispersion" is to be understood as meaning a dispersion concentrate based on an organic vehicle in which one or more dithiocarbamate compounds are suspended; further agrochemical active ingredients may be present in the dispersion.

DESCRIPTION OF THE INVENTION

It is therefore an object of the present invention a dithiocarbamate oil dispersion comprising : from 5.0 to 60 % by weight (wt%) of at least one fungicide of the family of the dithiocarbamates, from 10 to 90 wt% of an oil and from 0.05 to 10 wt% of a polyamide obtained by reacting in a first step: a) one mole of a polyamine having n amino groups with exchangeable hydrogens, wherein n is an integer ranging from 3 to 4;

b) from 1 to n-1 moles of a saturated or unsaturated C₆-C₃₀ aliphatic monocarboxylic acid or an ester thereof;

to obtain an aminoamide having an acid number below 30 mg_K0_H/g and, subsequently, reacting the remaining amino groups bearing exchangeable hydrogens of the aminoamide with :

c) from 0.3 to 1.0 mole of a C₂-Ci₀ di- or tri-carboxylic acid or with the corresponding anhydride for each mole of remaining amino groups to obtain a polyamide with a total amine value below 60 mg_K0_H/g·

It is a further object of the invention a method for the preparation of a dithiocarbamate oil dispersion comprising :

i) preparing a mixture comprising at least one fungicide of the family of the dithiocarbamates and an oil;

ii) adding to the mixture the above described polyamide;

said dithiocarbamate oil dispersion comprising from 5.0 to 60 wt% of said fungicide, from 10 to 90 wt% of oil and from 0.05 to 10 wt% of said polyamide.

It is another object of the invention a method for the treatment of plants, crops or fields comprising the step of:

i. providing a dithiocarbamate oil dispersion as described above;

ii. diluting said dithiocarbamate oil dispersion with water or a water solution of agronomic compounds to produce a sprayable composition; iii. applying to the plants, crops, or fields an effective amount of said sprayable aqueous composition.

DETAILED DESCRIPTION OF THE INVENTION

Preferably, the dithiocarbamate oil dispersion of the invention comprises: from 7.0 to 60 wt% of at least one fungicide of the family of the dithiocarbamates; from 20 to 80 wt% of an oil and from 0.1 to 5.0 wt%, more preferably from 0.2 to 3 wt%, of the polyamide described above.

The fungicide of the family of the dithiocarbamates can be chosen, for example, among amobam, asomate, azithiram, carbamorph, cufraneb, cuprobam, disulfiram, ferbam, metam, nabam, tecoram, thiram, urbacide, ziram, dazomet, etem, milneb, mancopper, mancozeb, maneb, metiram, polycarbamate, propineb and zineb. Preferred fungicides of the family of the dithiocarbamates are: mancozeb, maneb, thiram and ziram. Mancozeb being the most preferred.

The oil is a water-insoluble liquid organic medium and may be any of those oils commonly used in agriculture for making oil dispersions for agricultural use. Suitable oils for the dispersions of the invention are, for example:

• linear or branched C₈ to C₃₀ paraffins having boiling points above 140 °C (paraffin oils), for example octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, their mixtures, or mixtures thereof with higher boiling homologs, such as hepta-, octa-, nona-decane, eicosane, heneicosane, docosane, tricosane, tetracosane, pentacosane, and the branched chain isomers thereof.

• mineral oils, which are distillate fractions of mineral oil (petroleum), such as mixtures of open-chain linear or branched C_i4 to C₃₀ hydrocarbons.

• aromatic or cycloaliphatic, which may be unsubstituted or substituted, C₇ to Ci₈ hydrocarbons such as mono- or poly-alkylsubstituted benzenes, or mono- or poly-alkylsubstituted naphthalenes.

• vegetable oils such as liquid triglycerides for example olive oil, castor oil, palm oil, sesame oil, corn oil, rice bran oil, peanut oil, cotton seed oil, soybean oil, rapeseed oil, linseed oil, sunflower oil, safflower oil, or also trans-esterification products thereof, e.g. alkyl esters, such as rapeseed oil methyl ester or rapeseed oil ethyl ester.

• animal oil, such as whale oil, cod-liver oil, or mink oil.

• liquid esters of Ci to C₁₂ monoalcohols or polyols, for example butanol, n-octanol, i-octanol, dodecanol, cyclopentanol, cyclohexanol, cyclooctanol, ethylene glycol, propylene glycol or benzyl alcohol, with C₂ to Cio carboxylic or polycarboxylic acids, such as caproic acid, capric acid, caprylic acid, pelargonic acid, succinic acid and glutaric acid; or with aromatic carboxylic acids such as benzoic acid, toluic acid, salicylic acid and phthalic acid. Esters which can be used in the oil dispersions of the invention are thus, for example, benzyl acetate, caproic acid ethyl ester, pelargonic acid ethyl ester, benzoic acid methyl or ethyl ester, salicylic acid methyl, propyl, or butyl ester, diesters of phthalic acid with saturated aliphatic or alicyclic Ci to C_i2 alcohols, such as phthalic acid dimethyl ester, dibutyl ester, diisooctyl ester;

· liquid amides of amines, such as Ci-C₅ alkylamines or alkanolamines, with Ce-Cis carboxylic acids;

• mixtures thereof.

According to a particular embodiment, the oil is chosen among paraffin oils, mineral oils, in particular those having an aromatic portion of less than 8% by weight, vegetable oils or trans-esterification products thereof, and mixtures thereof.

The polyamine a) has n amino groups with exchangeable hydrogens, wherein n is an integer ranging from 3 to 4. More preferably n is 3.

Preferred polyamines include polyalkylene polyamines, for example those having formula I:

H₂N[(CH₂)_xNH]_yH I

where x is an integer ranging from 1 to 6 and y is an integer ranging from 2 to 3.

Examples of preferred polyalkylene polyamines of formula I are those wherein x is 2, that is the polyethylene amines, such as ethylene diamine, diethylene triamine, triethylene tetramine, tetraethylene pentamine and mixtures thereof.

Other preferred polyalkylene polyamines are polyethyleneimines with a average molecular weight of below about 300 dalton, which exhibit a low degree of branching. More preferably, the polyamine a) is a polyethylene amine chosen among diethylene triamine, triethylene tetramine and mixtures thereof. Diethylene triamine being the most preferred.

The C₆-C₃o aliphatic monocarboxylic acid b) (or its ester) can be both unsaturated and saturated.

Examples of C₆-C₃₀ aliphatic unsaturated monocarboxylic acids suitable for the preparation of the polyamide of the invention include both unsaturated and polyunsaturated aliphatic carboxylic acids with from 6 to 30 carbon atoms. Examples of these acids are palmitoleic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, and the like.

Examples of C₆-C₃₀ aliphatic saturated monocarboxylic acids include decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, and the like.

Mixtures of C₆-C₃₀ saturated and unsaturated aliphatic monocarboxylic acids can be also used.

In a preferred embodiment of the invention, the C₆-C₃₀ monocarboxylic acid b) is a mixture of C₁₂-C₂₂ saturated and unsaturated aliphatic monocarboxylic acids.

In a more preferred embodiment of the invention the C₆-C₃₀ monocarboxylic acid b) is a mixture of C₁₂-C₂₂ saturated and unsaturated aliphatic monocarboxylic acids comprising at least 40 % by weight, preferably at least 60 % by weight, of oleic acid.

Natural oils, such as coconut oil, mustard seed oil, palm oil, olein, soybean oil, canola oil, tall oil, sunflower oil, and mixture thereof, are particularly preferred sources of of monocarboxylic acids or mixtures thereof.

Mixtures of monocarboxylic acids obtained as by-product in the process of the biodiesel production are also suitable sources of C₆-C₃₀ saturated and unsaturated aliphatic monocarboxylic acids.

In a preferred embodiment of the invention the polyamine is reacted a saturated or unsaturated C₆-C₃₀ aliphatic monocarboxylic acid or a mixture of C₆-C₃₀ aliphatic monocarboxylic acids. Preferably, the monocarboxylic acid source is selected from tall oil, rape seed oil, soybean oil, by-products in the process of the biodiesel production and mixtures thereof.

The preparation of the aminoamide may be carried out according to methods well known to those skilled in the art. For example, by heating the polyamine a) and the monocarboxylic acid b) (or an ester thereof) up to 250 °C, preferably from 140 to 180 °C, either or not, in a suitable hydrocarbon solvent such as toluene or xylene and azeotroping off the formed water, with or without catalysts such as p-toluenesulphonic acid, zinc acetate, zirconium naphthenate or tetrabutyl titanate. Usually, the end-point of the reaction is considered to be reached when the acid number of the reaction mixture, determined by ASTM standard method D1980-87, is below 30 mg_K0H/g, preferably below 10 mg_K0H/g ·

When the polyamine used is diethylene triamine, preferably, in the first step one mole of diethylene triamine is reacted with from 1.4 to 2.0 moles of C₆-C₃o aliphatic monocarboxylic acid.

The di- or tri-carboxylic acid or the corresponding anhydride c), that can be reacted with the above-described aminoamides to form the polyamide of the present invention, has preferably from 3 to 8 carbon atoms, more preferably 4 carbon atoms.

Examples of suitable C₂-Ci₀ di- or tri-carboxylic acids include succinic acid, malonic acid, (ethylenedioxy) diacetic acid, maleic acid, diglycolic acid, tartaric acid, tartronic acid and fumaric acid; citric acid, aconitic acid, citraconic acid, carboxymethyloxysuccinic acid and lactoxysuccinic acid; phthalic acid; and mixtures thereof.

Preferably, the C₂-Ci₀ di- or tri-carboxylic acid c) is a C₃-C₈ di-carboxylic acid. Di-carboxylic acid which are particularly suitable for the realization of the present invention are fumaric acid, malonic acid, maleic acid, or their corresponding anhydrides; and mixtures thereof. Maleic acid being the most preferred.

The aminoamide containing amino groups with exchangeable hydrogens and the di- and/or tri-carboxylic acid (or corresponding anhydride) described above can be condensed at a temperature ranging from about 120 to about 250 °C, preferably from about 140 to about 200 °C, while the formed water is distilled off. The end-point of the reaction is considered to be reached when the total amine value of the reaction mixture, determined by ASTM standard method D2074-12, is below 60 mg 0_H/g, preferably below 40 mg_K0_H/g, more preferably below 20 mg_K0H/g-

Preferably, the acid number of the polyamide so obtained, determined by ASTM standard method D1980-87, is below 70 mg_K0H/g, more preferably it is comprised between 20 and 60 mg_K0_H/g·

In the preferred embodiment of the invention, the remaining amino groups with exchangeable hydrogens are reacted with from 0.4 to 0.9 moles, more preferably from 0.4 to 0.7 moles, of C₂-Ci₀ di- or tri carboxylic acid, preferably di-carboxylic acid, for each mole of remaining amino groups.

The polyamide obtained by reacting :

a) one mole of diethylene triamine;

b) from 1.4 to 2 mole of a mixture of saturated or unsaturated C12-C22 aliphatic monocarboxylic acids or esters thereof;

and, subsequently, reacting the remaining amino groups with exchangeable hydrogens of the aminoamide so obtained with :

c) from 0.4 to 0.7 mole of maleic acid or with the corresponding anhydride for each mole of remaining amino groups;

is particularly suitable for the realization of the present invention.

The above described polyamides show unexpectedly high stabilizing performances for dithiocarbamate oil dispersions, especially with vegetable oils and paraffin oils.

In a preferred embodiment, the dithiocarbamate oil dispersion of the invention further comprises from 5 to 30 wt%, preferably from 5 to 20 wt%, of at least one surfactant. Surfactants are used not only to improve dispersion and to emulsify oil upon dilution in water, but also to increase suspension stability, wetting ability and penetration, and to provide the mixing ability and suspension/emulsion stability of a product after dilution with water.

As surfactants, anionic, cationic, non-ionic and ampholytic surfactants and mixtures thereof can be used. Suitable surfactants are, for example, nonionic emulsifiers and dispersants, such as:

• polyalkoxylated, for example polyethoxylated and/or polypropoxylated, saturated and unsaturated, aliphatic alcohols, such as those having 8 to 24 carbon atoms in the alkyl radical and having 1 to 50, preferably 3 to 20, ethylene oxide and/or propylene oxide units;

• polyalkoxylated arylalkylphenols, such as, for example, polyalkoxylated tristyrylphenol having an average degree of alkoxylation of between 3 and 50, preferably from 5 to 25;

• polyalkoxylated alkylphenols, such as those having one or more alkyl radicals, such as, for example, polyalkoxylated nonylphenol or tri-sec- butylphenol, and a degree of alkoxylation of between 2 and 40, preferably from 4 to 20;

• polyalkoxylated hydroxyl-fatty acids or glycerides which contain hydroxyl-fatty acids, such as, for example, castor oil, having a degree of alkoxylation of between 10 and 80;

• sorbitan or sorbitol esters with fatty acids or polyalkoxylated sorbitan or sorbitol esters;

• polyalkoxylated amines;

• di- and tri-block copolymers, for example from alkylene oxides, for example from ethylene oxide and propylene oxide, having average molar masses from 200 to 8000 g/mol, preferably from 1000 to 4000 g/mol;

• alkylpolyglycosides or polyalkoxylated alkylpolyglycosides.

Preferred nonionic surfactants are polyalkoxylated, saturated and unsaturated, aliphatic alcohols, in particular alkoxylated aliphatic alcohols having 8 to 14 carbon atoms in the alkyl radical and 3 to 20 ethylene oxide and/or propylene oxide units, polyalkoxylated arylalkylphenols and di- and tri-block copolymers, in particular polyethylene oxide/polypropylene oxide block copolymers having average molar masses from 1000 to 4000 g/mol.

Also suitable are anionic surfactants, for example:

· polyalkoxylated surfactants which are ionically modified, for example by conversion of the terminal free hydroxyl function of the alkylene oxide block into a sulfate or phosphate ester;

• alkali metal and alkaline earth metal salts of alkylarylsulfonic acids having a straight-chain or branched alkyl chain;

· alkali metal and alkaline earth metal salts of paraffin-sulfonic acids and chlorinated paraffin-sulfonic acids;

• polyelectrolytes, such as lignosulfonates, condensates of naphthalenesulfonate and formaldehyde, and polystyrenesulfonates;

• anionic esters of alkylpolyglycosides, such as alkylpolyglucoside sulfosuccinates or citrates;

• salts of sulfosuccinic acid, which was esterified once or twice with linear, or branched aliphatic, cycloaliphatic and/or aromatic alcohols, or salts of sulfosuccinic acid, which was esterified once or twice with alkylene oxide adducts of alcohols.

Preferred anionic surfactants are polyalkoxylated nonionic surfactants which were ionically modified, salts of alkylarylsulfonic acids having a straight-chain or branched alkyl chain and anionic esters of alkylpolyglycosides.

Examples of cationic and ampholytic surfactants are quaternary ammonium salts, alkyl amino acids, and betaine or imidazoline amphotensides.

Nonionic surfactants are the preferred surfactants for the realization of the present invention.

The dithiocarbamate oil dispersion of the invention can further comprise from 0.55 to 50 wt%, preferably from 2 to 30 wt%, of at least another agrochemical active ingredient. Suitable additional agrochemical active ingredients for the dithiocarbamate oil dispersion are, for example, further fungicides, bactericides, insecticides, acaricides, nematicides, herbicides, aracnicides, insect growth regulators, repellents, antibiotics, plant growth regulators, plant nutrients and mixture thereof.

Examples of fungicides which may be mentioned are:

2-anilino-4-methyl-6-cyclopropyl-pyrimidine; 2',6'-dibromo-2-methyl-4'- trifluoro-methoxy-4'-trifluoromethyl-l,3-thiazole-5-carboxanilide; 2,6- dichloro -N-( 4-trifluoro-methylbenzyl)-benzamide; (E)- 2-methoximino-N -methyl- 2-(2-phenoxyphenyl)-acetamide; 8-hydroxyquinoline sulphate; methyl (E)-2-{2-[6-(2-cyanophenoxy)-pyrimidin-4-yloxy]-phenyl}-3- methoxyacrylate; methyl (E)-methoximino[alpha-(o-tolyloxy)-o-tolyl]- acetate; 2-phenylphenol (OPP), aldimorph, ampropylfos, anilazine, azaconazole, benalaxyl, benodanil, benomyl, binapacryl, biphenyl, bitertanol, blasticidin-S, bromuconazole, bupirimate, buthiobate, calcium polysulphide, captafol, captan, carbendazim, carboxin, quinomethionate, chloroneb, chloropicrin, chlorothalonil, chlozolinate, cymoxanil, cyproconazole, cyprofuram, carpropamide, dichlorophen, diclobutrazole, dichlofluanid, diclomezin, dicloran, diethofencarb, difenoconazole, dimethirimol, dimethomorph, diniconazole, dinocap, diphenylamine, dipyrithion, ditalimfos, dithianon, dodine, drazoxolon, edifenphos, epoxyconazole, ethirimol, etridiazole, fenarimol, fenbuconazole, fenfuram, fenitropan, fenpiclonil, fentin acetate, fentin hydroxide, ferimzone, fluazinam, fludioxonil, fluoromide, fluquinconazole, flusilazole, flusulfamide, flutolanil, flutriafol, folpet, fosetyl-aluminium, fthalide, fuberidazole, furalaxyl, fenhexamide, guazatine, hexachlorobenzene, hexaconazole, hymexazole, imazalil, imibenconazole, iminoctadine, iprobenfos (IBP), iprodion, isoprothiolan, iprovalicarb, kasugamycin, copper preparations, such as: copper hydroxide, copper naphthenate, copper oxychloride, copper sulphate, copper oxide, oxine-copper and

Bordeaux mixture; mepanipyrim, mepronil, metalaxyl, metconazole, methasulfocarb, methfuroxam, metsulfovax, mydobutanil, nitrothal- isopropyl, nuarimol, ofurace, oxadixyl, oxamocarb, oxycarboxine, pefurazoate, penconazole, pencycuron, phosdiphen, pimaricin, piperalin, polyoxine, probenazole, prochloraz, procymidon, propamocarb, propi- conazole, pyrazophos, pyrifenox, pyrimethanil, pyroquilon, quintozene (PCNB), quinoxyfen, sulphur and sulphur preparations, tebuconazole, tecloftalam, tecnazene, tetraconazole, thiabendazole, thicyofen, thiophanate-methyl, toldlophos-methyl, tolylfluanid, triadimefon, triadimenol, triazoxide, trichlamide, tricyclazole, tridemorph, trifiumizole, triforin, triticonazole, trifioxystrobin, validamycin A, vinclozolin, ciproconazole, dodine, fenamidone, fenexamide, fluopicolide, fluoxastrobin, fosetyl-aluminium, iprovalicarb, pencycuron, prothioconazole, spiroxamina, triadimenol, trifioxystrobin, azoxystrobin, acibenzolar-S-methyl, ciprodinil, mandipropamid, fenpropidin, boscalid, kresoxim-methyl, pyraclostrobin, dimetomorf, fenpropimorf, metraphenone, tolclofos-methyl and 2-[2-(l-chloro-cyclopropyl)-3-(2- chlorophenyl)- 2-hydroxypropyl]- 2, 4-dihydro-[l,2,4]-triazole-3-thione. Examples of bactericides which may be mentioned are:

bronopol, dichlorophen, nitrapyrin, kasugamycin, octhilinon, furancarboxylic acid, oxytetracycline, probenazole, streptomycin, tecloftalam, copper sulphate and other copper preparations.

Examples of insecticides, acaricides and nematicides which may be mentioned are:

abamectin, acephate, acrinathrin, alanycarb, aldicarb, alphamethrin, amitraz, avermectin, AZ 60541, azadirachtin, azinphos A, azinphos M, azocyclotin, Bacillus thuringiensis, 4-bromo-2-(4-chlorphenyl)-l- (ethoxymethyl)-5-(trifluoromethyl)-pyrrole-3-carbonitrile, bendiocarb, benfuracarb, bensultap, betacyfluthrin, bifenthrin, BPMC, brofenprox, bromophosa, bufencarb, buprofezin, butocarboxine, butylpyridaben, cadusafos, carbaryl, carbofuran, carbophenothion, carbosulfan, cartap, chloethocarb, chlaretoxyfos, chlorfenvinphos, chlorfluazuron, chlormephos, N-[(6-chloro-3-pyridinyl)-methyl]-N'-cyano-N-methyl- ethaneimidamide, chlorpyrifos, chlorpyrifos M, cis-resmethrin, clocythrin, clofentezin, cyanophos, cycloprothrin, cyfluthrin, cyhalothrin, cyhexatin, cypermethrin, cyromazin, deltamethrin, demeton-M, demeton-S, deme- ton-S-methyl, diafenthiuron, diazinon, dichlofenthion, dichlorvos, dicliphos, dicrotophos, diethion, diflubenzuron, dimethoate, dimethylvinphos, dioxathion, disulfoton, emamectin, esfen valerate, ethiofencarb, ethion, ethofenprox, ethoprophos, etrimphos, fenamiphos, fenazaquin, fenbutatin oxide, fenitrothion, fenobucarb, fenothiocarb, fenoxycarb, fenpropathrin, fenpyrad, fenpyroximate, fenthion, fenvalerate, fipronil, fluazuron, flucycloxuron, flucythrinate, flufenoxuron, flufenprox, fluvalinate, fonophos, formothion, fosthiazate, fubfenprox, furathiocarb, HCH, heptenophos, bexaflumuron, hexythiazox, imidacloprid, iprobenfos, isazophos, isofenphos, isoprocarb, isoxathion, ivermectin, lambdacybalothrin, lufenuron, malathion, mecarbam, mevinphos, mesulfenphos, metaldehyde, methacrifos, methamidophos, methidathion, methiocarb, methomyl, metolcarb, milbemectin, monocrotophos, moxidectin, naled, NC 184, nitenpyram, omethoate, oxamyl, oxydemethon M, oxydeprofos, parathion AL, parathion ML, permethrin, phenthoate, phorate, phosalon, phosmet, phosphamidon, phoxim, pirimicarb, pirimiphos M, pirimiphos A, profenophos, promecarb, propapbos, propoxur, prothiophos, prothoate, pymetrozine, pyrachlophos, pyridaphenthion, pyresmethrin, pyrethrum, pyridaben, pyrimidifen, pyriproxifen, quinalphos, salithion, ebufos, silafluofen, sulfotep, sulprofos, tebufenozide, tebufenpyrad, tebupirimiphos, teflubenzuron, tefluthrin, temephos, terbam, terbufos, tetrachlorvinphos, thiacloprid, thiafenox, thiamethoxam, thiodicarb, thiofanox, thiomethon, thionazine, thuringiensin, tralomethrin, transfluthrin, triarathen, triazophos, triawron, trichlorfon, triflumuron, trimethacarb, vamidothion, XMC, xylylcarb, zetamethrin, ethoprophos, fenpyroximate, methoxyfenozide, spinosad, spirodiclofen, thiacloprid, cypermethrine, alfacypermethrine, alphametrine e metaflumizone.

Examples of herbicides which may be mentioned are:

anilides, such as, for example, diflufenican and propanil; arylcarboxylic acids, such as, for example, dichlorpicolinic acid, dicamba and picloram; aryloxyalkanoic acids, such as, for example, 2,4-D, 2,4-DB, 2,4-DP, Fluroxypyr, MCPA, MCPP and triclopyr; aryloxy-phenoxy-alkanoic acid esters, such as, for example, diclofop-methyl, fenoxapropethyl, Fluazifop- butyl, haloxyfop-methyl and quizalofop-ethyl; azinones, such as, for example, chloridazon and norflurazon; carbamates, such as, for example, chlorpropham, desmedipham, phenrnedipham and propham; chloroacetanilides, such as, for example, alachlor, acetochlor, butachlor, metazachlor, metolachlor, pretilachlor and propachlor; dinitroarilines, such as, for example, oryzalin, pendimethalin and trifluralin; diphenyl ethers, such as, for example, acifluorfen, bifenox, fluoroglycofen, fomesafen, halosafen, lactofen and oxyfluorfen; ureas, such as, for example, chlortoluron, diuron, fluometuron, isoproturon, linuron and methabenzthiazuron; hydroxylamines, such as, for example, alloxydim, clethodim, cycloxydim, sethoxydim and tralkoxydim; imidazolinones, such as, for example, imazethapyr, imazamethabenz, imazapyr and imazaquin; nitriles, such as, for example, bromoxynil, dichlobenil and ioxynil; oxyacetamides, such as, for example, mefenacet; sulfonylureas, such as, for example, amidosulfuron, bensulfuron-methyl, chlorimuron-ethyl, chlorsulfuron, cinosulfuron, metsulfuron-methyl, nicosulfuron, primisulfuron, pyrazosulfuron-ethyl, thifensulfuron-methyl, triasulfuron and tribenuron-methyl; thiocarbamates, such as, for example, butylate, cycloate, diallate, EPTCL, esprocarb, molinate, prosulfocarb, thiobencarb and triallate; triazines, such as, for example, atrazine, cyanazine, simazine, simetryne, terbutryne and terbutylazine; triazinones, such as, for example, hexazinon, metarnitron and metribuzin; others, such as, for example, aminotriazole, benfu resate, bentazone, cinmethylin, clomazone, clopyralid, difenzoqual, dithiopyr, ethofumesate, fluorochloridone, glu- fosinate, glyphosate, isoxaben, pyridate, quinchlorac, quinmerac, sulphosate and tridiphane, aclodifen, bap, bispyribac-sodium, ethoxysulfuron, flufenacet, foramsulfuron, iodosulfuron methyl sodium, isoxadifen ethyl, isoxaflutole, mefenpyr diethyl, mesosulfuron methyl, sulcotrione, mesotrione, prosulfuron, florasulam, clodinafop propargyl, pinoxaden, trinexapac ethyl, dimethenamide-P, imazamox, profoxydim, tepraloxidim.

Examples of plant growth regulators which may be mentioned are chlorocholine chloride and ethephon.

Examples of repellents which may be mentioned are diethyl-toluamide, ethylhexane-diol and buto-pyronoxyl.

Other classes of pesticides that are suitable for formulating in the dithiocarbamate oil dispersions of the invention, will be clearly understood by those skilled in the art or can be found, for example, in "The Pesticide Manual", 15th edition, The British Crop Protection Council, 2009, and the literature cited therein.

Examples of plant nutrients, which can be added to the dithiocarbamate oil dispersion of the invention, are customary inorganic or organic fertilizers for supplying plants with macro- and/or micro-nutrients, such as: ammonia salts, such as ammonium sulfate, ammonium bisulfate, ammonium salts of carboxylic acids, ammonium chloride, ammonium carbonate, ammonium phosphate, urea and urea derivatives; phosphorus sources, such as phosphoric salts (MAP monoammoniumphosphate, DAP diammoniumphosphate); potash sources, like potassium phosphate and mono- or di-potassium carbonate; compounds containing micronutrients and secondary nutrients like Zinc, Manganese, Magnesium, Iron, Calcium, Nickel, Molibdenum, Sulfur, Boron, and their chelated salts; polycarboxylic acids, such as citric acid; and mixtures thereof; protein derivatives and hydrolyzed proteins and mixtures thereof. Preferred plant nutrients are MAP, ammonium sulfate , sulfur, urea and urea derivatives.

The dithiocarbamate oil dispersion of the invention can comprise from 0.01 to 5 % wt of a thickener to further improve the stability of the composition. Suitable thickeners are for example thickeners based on natural polymers, such as cellulose derivatives; hydrogenated castor oil or polyhydroxystearic acid; bentones and modified silica. Natural oils and derivatives thereof, are the preferred thickeners. The oil dispersion according to the invention can comprise from 0.5 to 35 wt% of adjuvants commonly used in this field and well known to those expert in the art, such as wetting agents, antidrift agents, penetrants and stickers.

In addition to each of the aforementioned components said oil dispersion may also comprise from 0.1 to 10 wt% of other agronomic additives and "crop management" substances such as oil-soluble agrochemical active ingredients, water soluble carrier and/or deflocculation agents (e. g. kaolin, lignin compounds), antifoam agents (e.g. silicon-based), antifreeze agents, dyes (e. g. azo dyes), preservatives (e. g. biocide and/or antioxidant), fillers, perfumes, evaporation inhibitors, pH modulators, etc.

The oil suspensions according to the invention can be prepared in a manner known per se.

In the method of the invention, the solid active ingredients are preferably employed in the finely ground state, that is as a micronized powder of less than 50 microns in size on average, preferably of less than 20 microns, more preferably less than 10 microns, or they may be reduced to this particle average size during any step of the dispersion preparation. In one embodiment, it is possible to prepare the dispersion by first coarse wet-milling and then fine wet-milling the active ingredient, in the presence of the oil, so that the final average particle size of the dithiocarbamate is below 50 microns, preferably below 20 microns. Milling can be carried out in a colloid mill, ball mill, sand mill, and preferably in grinding ball mills.

In a further embodiment, it is possible to prepare the dispersion by mixing the oil, the possible other liquid additives and the solid ingredients that have been preliminarily pulverized to an average particle size of from about 20 to 50 microns by a dry mill and then, optionally, subjecting the mixture to fine treatment by a wet-mill, such as a ball mill or a sand mill, so that the final average particle size of the dithiocarbamate is below 20 microns, preferably below 10 microns. The described polyamide is preferably added after milling, but, since it does not increase the viscosity of the dispersion of the invention, it can be also added before milling. It can be poured into the liquid as such, preferably heated at a temperature above 40 °C, or can be predispersed or predissolved in on oil and then added to the grinded mixture.

The dithiocarbamate oil dispersions of the invention have Brookfield RV® viscosity at 25°C and 20 rpm of at least 300 mPa_*s, preferably of at least 1000 mPa_*s, , and usually below 25,000 mPa_*s, preferably below 10,000 mPa_*s.

The dithiocarbamate oil dispersion can be diluted with water or water solutions of agronomic compounds before use to produce a sprayable composition, which is used in treating plants or crops. Dilution in water usually results in suspensions, emulsions, suspoemulsions or solutions of the dithiocarbamate at a concentration of at least 0.001 g/l. It may be advantageous to add, to the aqueous composition obtained, further agrochemical active substances and/or adjuvants and additives conventionally used for application, for example stickers or antidrift agents.

The invention also relates to sprayable aqueous compositions obtained by dilution of a dithiocarbamate oil dispersions according to the present invention.

The invention also relates to a method which comprises applying to the plants or to the locus thereof an effective amount of a sprayable aqueous compositions obtained by dilution of the dithiocarbamate oil dispersion according to the present invention. Application may be made by ground or aerial spray equipment. The amount of active ingredient applied may vary within a relatively wide range. It depends essentially on the nature of the desired effect. In general, the application rates are at least 0.01 g of active ingredient per hectare of soil surface. EXAMPLES

Characterization Methods

The acid number was determined following the ASTM standard method D1980-87.

The total amine value was determined following the ASTM standard method D2074-12.

The Brookfield RV® viscosity (mPa_*s) was determined at 25 °C and 20 rpm using a Brookfield RV® viscosimeter.

Ingredients

In the Examples the following ingredients were used :

• Tall Oil Fatty Acids (TOFA);

• Linolenic Acid;

• Diethylene Triamine (DETA);

• Triethylene Tetramine (TETA);

· Maleic Anhydride (MA);

• Citric Acid, anhydrous;

• Fumaric Acid;

• Mancozeb, 85 wt% active substance;

• Methiram, 85 wt% active substance;

· Maneb, 98 wt% active substance;

• BANOLE, paraffin oil from Total SA;

• EDC 95/11, hydrocarbons, Ci₅-C₂o, n-alkanes, isoalkanes, cyclics, < 0.03% aromatics, from Total SA;

• FLUID GENERA 9, paraffin oil from Total SA;

· Soy Lecithin;

• CHIMIPAL AC/9, ethoxylated fatty alcohol from Lamberti S.p.A.;

• EMULSON AG/CAL E, alkylbenzene sulfonate from Lamberti S.p.A.;

• ESATERGE 15 S5, alkoxylated fatty alcohol from Lamberti S.p.A.;

• AEROSIL 200, hydrophilic fumed silica, from Evonik Resource Efficiency GMBH;

• FLUIDIFICANTE FD, polyester based dispersant, from Lamberti S.p.A. Polyamide Preparation

Polyamide 1

842.4 g of TOFA were loaded in a 2000 ml glass reactor equipped with a Dean-Stark apparatus and a mechanical blade stirrer and heated to about 50 °C. Then 187.6 g of DETA were added. The reaction mixture was further heated to 160 °C under nitrogen atmosphere and maintained at this temperature for 3 hours. At the end of the reaction, the acid number of the aminoamide was below 10 mg_K0_H/g·

Subsequently, the mass was cooled to about 80 °C and 151.4 g of MA were slowly added. The reaction temperature was increased to 180 °C and maintained at this value for 60 min. The obtained polyamide had a total amine content below 26 mg_K0_H/g and an acid number of about 18 mg_K0H/g-

The polyamide was then diluted in EDC 95/11, to a final concentration of 65% by weight based on the weight of the final solution.

Polyamide 2

650.2 g of TOFA were loaded in a 2000 ml glass reactor equipped with a Dean-Stark apparatus and a mechanical blade stirrer and heated to about 50 °C. Then 146.2 of TETA were added. The reaction mixture was further heated to 160 °C under nitrogen atmosphere and maintained at this temperature for 3 hours. At the end of the reaction, the aminoamide had an acid number below 20 mg_K0H/g.

Subsequently, the mass was cooled to about 90 °C and 98.1 g of MA were slowly added. The reaction temperature maintained at 90 °C for 60 minutes. The obtained polyamide had a total amine content below 50 mg _0H/g and an acid number below 45mg_KOH/g·

The polyamide was then diluted in EDC 95/11, to a final concentration of 65% by weight based on the weight of the final solution.

Polyamide 3

578 g of TOFA were loaded in a 2000 ml glass reactor equipped with a

Dean-Stark apparatus and a mechanical blade stirrer and heated to about 50 °C. Then 103.2 g of DETA were added. The reaction mixture was further heated to 160 °C under nitrogen atmosphere and maintained at this temperature for 3 hours. At the end of the reaction, the aminoamide had an acid number below 20 mg_K0_H/g·

Subsequently, the mass was cooled to about 140 °C and 192 g of Citric Acid were slowly added. The reaction temperature was increased to 160 °C and maintained at this value for 60 minutes. The obtained polyamide had a total amine content below 20 mg_K0_H/g and an acid number of about 40 mg_K0H/g.

The polyamide was then diluted in EDC 95/11, to a final concentration of 65% by weight based on the weight of the final solution.

Polyamide 4

578 g of TOFA were loaded in a 2000 ml glass reactor equipped with a Dean-Stark apparatus and a mechanical blade stirrer and heated to about 50 °C. Then 103.2 g of DETA were added. The reaction mixture was further heated to 160 °C under nitrogen atmosphere and maintained at this temperature for 3 hours. At the end of the reaction, the aminoamide had an acid number below 20 mg_K0_H/g·

Subsequently, 116.1 g of Fumaric Acid were slowly added. The reaction temperature was increased to 180 °C and maintained at this value for 120 minutes. The obtained polyamide had a total amine content below 20 mg 0_H/g and an acid number of about 40 mg_K0_H/g and was liquid at room temperature.

The polyamide was then diluted in EDC 95/11, to a final concentration of 65% by weight based on the weight of the final solution.

Polyamide 5

314.1 g of linolenic acid were loaded in a 1000 ml glass reactor equipped with a Dean-Stark apparatus and a mechanical blade stirrer and heated to about 50 °C. Then 68.67 g of DETA were added. The reaction mixture was further heated to 155 °C under nitrogen atmosphere and maintained at this temperature for 3 hours. At the end of the reaction, the acid number of the aminoamide was below 20 mg_K0_H/g- Subsequently, the mass was cooled to about 90 °C and 65.3 g of MA were slowly added. The reaction temperature was increased to 165 °C and maintained at this value for 90 min. The obtained polyamide had a total amine content below 50 mg_K0H/g.

The polyamide was then diluted in EDC 95/11, to a final concentration of 65% by weight based on the weight of the final solution.

Oil Dispersion Stability Test

The dithiocarbamate/oil mixtures were prepared by vigorously mixing the oil, the surfactants and the agrochemical active ingredient. The mixtures were milled with a ball mill until a optimal particle size distribution was reached (D50 <2mGh; D90 <5mGh; determined with a laser light scattering spectrometer Malvern Mastersizer 2000). The recipes in grams for 100 grams of dithiocarbamate oil dispersions are summarized in Table 1. The stabilizers of the invention (Polyamides 1-5 ) and of the comparative stabilizers (Aerosil 200 and Fluidificante FD), as such or pre- dissolved/pre-dispersed at a concentration of 25 wt% in the oil, were added to the various mixtures after milling.

All oil dispersions were homogeneous and did not show any lumps or gels. The stability test /storage stability test) were performed at room temperature and at 54 °C on each dithiocarbamate oil dispersion in order to monitor over time the appearance of the dispersions, in particular the presence or absence of an oil phase or of a creamy phase in the composition, the presence or absence aggregations or sediments, and the presence or absence of supernatants. For this purpose, about 100 ml of the agrochemical oil dispersions were sealed in glass containers and allowed to rest at room temperature (r.t.) and in a oven at 54 °C. Table 2 reports the results of the test. "Thixotropic" means that the dispersion has become sharply more viscous, but it is still flowable after agitation. "Gel" means that the dispersion has become extremely viscous and it is not flowable anymore, even after agitation. Table 1

* Comparative

Table 2

Table 3

* Comparative

The results demonstrate that the polyamides of the invention do not increase the viscosity of the oil dispersions, do not form gel or lumps upon dissolution and have very good stabilization performances,.

The dithiocarbamate oil dispersions according to the invention can be easily prepared and show a good stability over the time, also at elevated temperatures. These dispersions are pourable, even after long storage, dispersible into water using minimal agitation and have very little tendency to form films in water, which can easily plug nozzle sieves.

Claims

1) A dithiocarbamate oil dispersion comprising : from 5.0 to 60 by weight (wt%) of at least one fungicide of the family of the dithiocarbamates, from 10 to 90 wt% of an oil and from 0.05 to 10 wt% of a polyamide obtained by reacting in a first step:

a) one mole of a polyamine having n amino groups with exchangeable hydrogens, wherein n is an integer ranging from 3 to 4 with

b) from 1 to n-1 moles of a saturated or unsaturated C₆-C₃₀ aliphatic monocarboxylic acid or an ester thereof;

to obtain an aminoamide having an acid number below 30 mg_K0_H/g and, subsequently, reacting the remaining amino groups bearing exchangeable hydrogens of the aminoamide with :

c) from 0.3 to 1.0 moles of a C₂-Ci₀ di- and/or tri-carboxylic acid or the corresponding anhydride for each mole of remaining amino groups;

to obtain a polyamide with a total amine value below 60 mg_K0H/g -

2) The dithiocarbamate oil dispersion of claim 1), comprising : from 7.0 to 60 wt% of at least one fungicide of the family of the dithiocarbamates; from 20 to 80 wt% of an oil and from 0.1 to 5.0 wt% of said polyamide.

3) The dithiocarbamate oil dispersion of claim 1), wherein said polyamine a) is a polyalkylene polyamine of formula I:

H₂N[(CH₂)_xNH]_yH I

where x is an integer ranging from 1 to 6, and y is an integer ranging from 2 to 3.

4) The dithiocarbamate oil dispersion of claim 3), wherein, said polyamine a) is a polyalkylene polyamine of formula I in which x is 2, that is a polyethylene amine.

5) The dithiocarbamate oil dispersion of claim 1), wherein the C₆-C₃₀ aliphatic saturated or unsaturated monocarboxylic acid b) is a mixture of C₁₂-C₂2 aliphatic saturated or unsaturated monocarboxylic acids.

6) The dithiocarbamate oil dispersion of claim 1), the C₂-Ci₀ di- or tri carboxylic acid c) is a C₃-C₈ di-carboxylic acid.

7) The dithiocarbamate oil dispersion of claim 1), wherein said oil is selected in the group consisting of linear or branched C₈ to C₃₀ paraffins having boiling points above 140 °C (paraffin oils); mineral oil; aromatic or cycloaliphatic C₇ to Ci₈ hydrocarbon compounds; vegetable oils or transesterification products thereof; animal oils; liquid esters of Ci to C₁₂ monoalcohols with C₂ to Ci₀ carboxylic or polycarboxylic acids; liquid amides of Ci to C₅ amines alkylamines or alkanolamines with C₆ to Ci₈ carboxylic acids; and mixtures thereof.

8) The dithiocarbamate oil dispersion of claim 7), wherein the oil is chosen among paraffin oils, mineral oils, vegetable oils or trans esterification products thereof, and mixtures thereof.

9) The dithiocarbamate oil dispersion of claim 1), further comprising from 5 to 30 wt% of at least one surfactant.

10) A method for the treatment of plants, crops, a or fields comprising the steps of:

i. providing a dithiocarbamate oil dispersion according to claims from 1) to 9);

ii. diluting said dithiocarbamate oil dispersion with water or a water solution of agronomic compounds to produce a sprayable composition;

iii. applying to the plants, crops or fields an effective amount of said sprayable aqueous composition.