FR2782243A1 - Solid phytosanitary compositions for tank mixing contain a silicone antifoam agent with a Brookfield viscosity of at least 8 Pa s - Google Patents

Abstract

Solid phytosanitary compositions are prepared by grinding a preferably aqueous suspension of a phytosanitary active material with a surfactant, and, an anti-foaming agent, a silicone having a Brookfield viscosity at 25 deg C of at least 8 Pa.s, and the ground mixture is dried to form a solid. Preferably, the anti-foaming agent of formula (I) has a Brookfield viscosity at 25 deg C of at least 20 Pa.s. ((R<1>)3SiO)-(R<2>R<4>SiO)x-((R<3>)2SiO)y-((R<1>)3SiO) (I) R<1> = 1-10C alkyl, 2-10C alkenyl, or aryl, aryl alkyl, alkyl aryl, aryl alkenyl, or alkenyl aryl in which the aryl groups have 5 - 10C and the alkyl and alkenyl groups have up to 4 C , or OH; R<2>, R<3>, and R<4> = a group as defined for R<1> but may not be OH; x and y = numbers that result in the (I) having the desired viscosity. The final solid compositions preferably contain 0.1 - 2% by weight of antifoaming agent. The antifoaming agent is preferably used as a compound with a mineral charge, such as a precipitated or calcined silica, especially one given a surface treatment to render it hydrophobic, quartz, calcined clays, diatomaceous earths, group IIA or IIIB oxides, hydroxides or sulfates, mica, or gypsum, alone or in admixture. The suspensions are preferably spray-dried giving solid compositions that may contain 50 - 95%, and preferably 20 - 60% of active material. The surfactant is principally present as a wetting agent, N-methyl-N-oleyl taurates, alkyl aryl sulfonates, alkyl benzene sulfonates, alkyl diphenyl ether sulfonates, alkyl naphthalene sulfonates, alkyl sulfo succinates, and ethoxylated alkyl phenols, alone or in admixture, being suitable.

Description

PREPARATION OF A SOLID PHYTOSANITARY COMPOSITION BY

ATOMIZATION IN THE PRESENCE OF AN ANTI-FOAM AGENT

The present invention relates to a process for preparing phytosanitary compositions in solid form, obtained by grinding and then drying a

suspension comprising the active material.

More particularly, the invention relates to a process using a particular anti-foaming agent, which can be introduced at the time of the preparation of the phytosanitary composition and which is capable of retaining its activity during

reuse of the latter.

The phytosanitary compositions, in addition to the active materials and fillers, contain surfactants, which have, among other things, the role of improving the wetting and the dispersion of the compositions during their use. However, very often these surfactants are the cause of difficulties associated with the production of foam; difficulties encountered, not only during the preparation of these compositions, but also, and

above all, during their use.

This is why it is known to add during the manufacture of the plant protection composition, then during the use (dilution / dispersion) of the latter, an anti-foaming agent. It is in fact necessary to proceed in two stages, since most defoamers lose their properties during the manufacture of the phytosanitary composition when they are subjected to high degrees of shearing. This is particularly the case for the preparation of water-dispersible granules, which are obtained by grinding a suspension comprising the active material and the surfactants,

followed by spray drying of the resulting suspension.

The drawbacks linked to this two-part solution are, on the one hand, that the user must use the anti-foaming agent in a tank-mix, and on the other hand that he

It is not always easy to dose the formulation and the defoamer correctly.

Another solution would be to add the second anti-foaming agent, no longer at the time of dilution of the phytosanitary composition but during the process for preparing the composition, either before drying or once the latter has dried. However, such a solution requires the use of appropriate mixing devices and the implementation of an additional operation which may result in a

deterioration of the granules obtained.

One of the objectives of the present invention is to provide a composition which does not

not having the aforementioned drawbacks.

These aims and others are achieved by the present invention which therefore relates to a process for preparing phytosanitary compositions in solid form, in which a suspension is carried out comprising at least one phytosanitary active material, at least one surfactant. and at least one anti-foaming agent, followed by drying to obtain the phytosanitary composition in solid form. The process according to the invention is characterized in that the grinding is carried out with a suspension comprising at least one anti-foaming agent chosen from silicone substances having a Brookfield viscosity measured at 25 ° C., greater than or equal to

8 Pa.s.

The choice of this particular type of silicone anti-foaming agent makes it possible to have an acceptable level of foam during the grinding operation, and conservation of

these properties at the time of dilution (dispersion) of the composition by the user.

Such a result being obtained without having to add an anti-foaming agent, neither when the composition is used, nor after its drying. In addition, completely unexpectedly, this result could be obtained without having to add an anti-foaming agent after the suspension of active material has undergone a significant shearing operation.

(grinding).

But other advantages and features will become more apparent at

reading the description and the examples which follow.

The anti-foaming agent used in the process according to the invention is therefore chosen from silicone substances, also exhibiting a Brookfield viscosity.

measured at 25 C, greater than or equal to 8 Pa.s.

According to a particular embodiment of the invention, at least one anti-foaming agent is used having a Brookfield viscosity measured at 25 C,

greater than or equal to 10 Pa.s, preferably greater than or equal to 20 Pa.s.

The silicone substance (or silicone) is more particularly chosen from polyorganosiloxanes in which at least 50% of the organic substituents are

methyl radicals.

The other radicals of the silicone substance can be hydrogen atoms, hydroxyls, alkyl radicals, linear or branched in C1-C1o, alkenyl radicals, linear or branched, in C2-C1o, aryl or alkylaryl radicals in Cs -C10o More particularly, the silicone substances used correspond to the following formula: [(R1) 3SiO] - [R2R4SiO] X - [(R3) 2SiO] y [(R1) 3SiO] in which: - the radicals R1, identical or different, substituted or not, represent a linear or branched alkyl, C1-Clo; an alkenyl radical, linear or branched, C2-C10; an aryl, alkyl-aryl, aryl-alkyl, aryl-alkenyl, alkenyl-aryl radical, C5-C10 for the aryl part and C1-C4 for the alkyl or alkenyl part, or a hydroxyl; - the radicals R2, R3, R4, substituted or not, identical or different, represent a linear or branched alkyl, C1-C10o; a linear or branched alkenyl radical, C2-C10o; an aryl, alkyl-aryl, aryl-alkyl, aryl-alkenyl, alkenyl-aryl radical, C5-C10 for the aryl part and C1-C4 for the alkyl or alkenyl part; - x and y represent average numbers of units, chosen to ensure the Brookfield viscosity greater than or equal to 8 Pa.s, more particularly 10 Pa.s, of

preferably 20 Pa.s.

More particularly, silicone oils are used for which the radicals R1, which are identical or different, represent methyl, ethyl, vinyl, phenyl and hydroxyl radicals. Preferably, the preferred R 1 radicals are methyl or hydroxyl radicals. More particularly, suitable silicones comprising only terminal methyl radicals, or else silicones having, in each of the

ends, one hydroxyl radical and two methyl radicals.

As regards the radicals R2, R3, R4, the methyl, ethyl, vinyl and phenyl radicals are preferred. It should be noted that according to a particular embodiment, at

at least 80% of said radicals are methyls.

As preferred examples, there may be mentioned: (CH3) 3Si-O - [(CH3) 2-SiO] zSi (CH3) 3 or [(CH3) 2 (OH)] Si-O - [(CH3) 2Si -O] z-Si [(CH3) 2 (OH)] with z representing a number of sufficient value to ensure a Brookfield viscosity greater than or equal to 8 Pas, more particularly 10 Pa.s, preferably

Not.

Obviously, it would not be departing from the scope of the present invention by

using a mixture of these two compounds.

The silicone substance used can be in the form of an oil,

or even a compound.

It should be noted that the term compound is a conventional term in the field of silicones, and which denotes a silicone substance associated with at least one mineral filler. We use compounds whose Brookfield viscosity is greater than or

equal to 8 Pa.s, more particularly 10 Pa.s, preferably 20 Pa.s.

Generally, the mineral fillers used to obtain the compounds have a specific surface, measured according to BET methods, of at least m2 / g, in particular between 50 and 400 m2 / g, preferably greater than 70 m2. / g. They also have an average particle size of less than

0.1 µm and an apparent density of less than 200 g / l.

More particularly, the mineral filler is chosen from silica, crushed quartz, calcined clays, or even diatomaceous earths, oxides, hydroxides or sulphates of elements from columns IIA, IIIB of the periodic table of

elements, mica, gypsum, singly or in mixtures.

Preferably, the mineral filler associated with the silicone substance is silica. This can be in precipitated or calcined form. It may optionally have undergone a surface treatment aimed at hydrophobizing it. It should be noted that this treatment can be carried out beforehand or in situ. Conventionally, the hydrophobation treatment consists in contacting the silica with one or more organosilicon compounds. Among these compounds, mention may be made of methylpolysiloxanes such as hexamethyldisiloxane, octamethylcyclotetrasiloxane, methylpolysilazanes such as hexamethyldisilazane, hexamethylcyclotrisilazane, chlorosilanes such as dimethyldichlorichlorichlorochloran, levinichlorichlorichlorochloran, levinichlorichlorichlorochloran, levinichlorichlorichlorichloran, levinichlorichlorichloran, levinichlorichlorichlorichlorine, dichlorichlorichlorichlorine, chlorosilane, dimethyllorichlorichlorichlorichlorichlorichloride. alkoxysilanes such as

dimethylmethoxysilane, MQ resins.

During this treatment, the silicas can increase their starting weight up to

a rate of 20%.

According to a particularly advantageous embodiment of the invention, a compound is used, the mineral filler of which is precipitated silica. Of

preferably, the silica entering into the composition of the compound is hydrophobic.

It has been found that the higher the viscosity of the silicone substance, the less critical the hydrophobic character of the filler, and more particularly of the silica. However, a particularly advantageous embodiment of the invention consists in using a silicone substance of high viscosity with

* a filler, and more particularly silica, made very hydrophobic.

Conventionally, in a compound, the proportion of silicone relative to the mineral filler, and more particularly relative to the silica, varies between 2 and 15 and

preferably between 2 and 10.

The compounds are prepared in the usual way by mixing the two components, then heating the mixture obtained between 60 and 200 C, in particular at

around 150 C, preferably under reduced pressure.

If a hydrophobation treatment is carried out in situ, the silica undergoes a heat treatment at a temperature above 100 - 150 C, in the absence of

silicic compounds mentioned above.

The anti-foaming agent used in the invention can be in the form of an oil, of a compound, but also of an emulsion. Such an embodiment is advantageous in that the anti-foaming agent becomes easier to use, because the viscosity of the emulsion is very low, while retaining its advantageous properties because the viscosity of the anti-foaming agent. - foam, as such, always remains greater than or equal to 8 Pa.s, preferably greater than or equal to 10 Pa.s,

more particularly greater than or equal to 20 Pa.s.

When the silicone substance is used in the form of an emulsion, the continuous medium can be chosen from water or any other compound which does not dissolve,

or substantially not, the silicone substance.

Among the silicone compounds, in the form of an oil, an emulsion or a compound, available commercially and capable of entering into the composition according to the invention, there may be mentioned, for example, the compound Rhodorsil 471, marketed by

the Rhodia company.

It should be noted that the composition according to the invention can comprise one or more silicone substances, as such or combined with one or more mineral fillers. The total amount of anti-foaming agent in the phytosanitary composition represents 0.1 to 2% by weight relative to the total weight of the composition.

phytosanitary in solid form.

The process according to the invention is suitable for the preparation of plant protection compositions in solid form, and more particularly in the form of dispersible granules. By phytosanitary composition is meant any composition intended for applications in the field of agriculture, comprising at least one biologically active material, such as pesticides in particular. The term “pesticides” denotes, inter alia, herbicides, fungicides, acaricides, insecticides and nematicides. It should be noted that if the method according to the invention can be used for any type of plant protection active material, it is nevertheless particularly suitable for

solid active substances, insoluble or sparingly soluble in water.

By way of nonlimiting example of suitable active materials, mention may be made, inter alia, of Ametryne, Diuron, Linuron, Chlortoluron, Isoproturon, Nicosulfuron, Metamitron, Diazinon, Glyphosate, Aclonifen, '' Atrazine, Chlorothalonil, Bromoxynil, Bromoxynil heptanoate, Bromoxynil octanoate, Glufosinate, Mancozeb, Maneb, Zineb, Phenmedipham, Propanyl, the phenoxyphenoxy series, the heteroxyPénoxy series, the Coxyphenoxy series, the Coxyphenoxy, the Coxyph MPA , 2,4-D, Simazine, the active products of the imidazolinones series, the organophosphate family, with in particular Azinphos-ethyl, Azinphos-methyl, Alachlor, Chlorpyriphos, Diclofop-methyl , Fenoxaprop-p-ethyl, Methoxychlor,

Cypermethrin, Fenoxycarb.

The amount of active material in the solid phytosanitary composition more particularly represents 50 to 95% by weight relative to the total weight of the product.

solid phytosanitary composition.

As has been indicated previously, the phytosanitary composition comprises at least one surfactant. Among the suitable surfactants, mention may be made of surfactants exhibiting

mainly a role of wetting agent.

Among suitable wetting agents, there may be mentioned without intention to be limited thereto, N-methyl-N-oleoyl taurates; salts of alkylarylsulphonates, such as salts of alkylbenzene sulphonates, salts of alkyl-diphenyl ether sulphonates, salts of alkylnaphthalene sulphonates; mono-alkyl sulfosuccinates, di-alkyl sulfosuccinates; ethoxylated alkylphenols. These wetting agents can be

used alone or as a mixture.

Mention may be made, for example, as wetting surfactants, of Geropon SDS, Geropon T / 77, Supragil NC / 85, Rhodacal DS / 10, Supragil WP,

marketed by Rhodia Chimie.

The amount of wetting agent can be between 0.5 and 10% by weight, relative to the total weight of the solid phytosanitary composition, preferably between 1 and% by weight, relative to the same reference. The solid phytosanitary compositions according to the present invention can also comprise at least one surfactant having mainly a role of dispersing agent. Among the dispersing agents suitable in the context of the present invention, there may be mentioned, inter alia, the alkali metal or ammonium salts of alkylnaphthalene sulfonates condensed with formalin; the alkali metal or ammonium salts of 4,4-dihydroxybiphenylsulfonate condensed with formalin; alkali metal or ammonium salts of alkylarylphosphates or cralkylarylsulphates, such as mono-, di- or tri-styrylphenols, polyoxyethylenated and / or polyoxypropylenated, phosphated or sulphated, neutralized or not; alkali metal, alkaline earth metal or ammonium lignosulphonates; and their mixtures. It should be noted that ammonium has the same following meaning: -N (R3) 3+, with R3, identical or different, representing

hydrogen atoms, or C1-C4 hydrocarbon radicals.

The ethylene oxide / propylene oxide copolymers are also compounds which can be used as dispersing agents. Suitable in particular

compounds having a molecular mass of between 3000 and 25000 g / mol.

Also suitable are alkali metal or ammonium salts of polymers comprising at least one monomer chosen from acids, diacids or unsaturated C3-C5 anhydrides, optionally combined with at least one monomer.

chosen from hydrocarbon radicals, unsaturated, linear or branched C4-C8.

More particularly, one can use polymers comprising as monomers, maleic acid, maleic anhydride, acrylic acid, methacrylic acid, alone or as mixtures. Said polymers can likewise

comprise at least one monomer chosen from isobutylene or diisobutylene.

This polymer can be in an acid form or else in an alkali metal or ammonium salt form of the -N (R3) 3+ type, with R3, identical or different, representing hydrogen atoms, or radicals. hydrocarbons in

C1-C4. Preferably, the copolymer is in the form of sodium salts.

Preferably, a polymer is used comprising maleic acid,

and / or maleic anhydride combined with isobutylene and / or diisobutylene.

The combination of an alkylbenzenesulphonate salt (such as more particularly, sodium alkylbenzenesulphonate, and preferably sodium dodecylbenzene sulphonate) with the aforementioned polymer, that is to say ie the polymer comprising maleic acid, and / or maleic anhydride combined with isobutylene and / or diisobutylene, preferably in the form of a sodium salt. The weight ratio of salt to polymer being more particularly / 90. By way of nonlimiting illustration, the dispersing agents can be chosen from the following products: Geropon 1 T / 36, Geropon TA / 72, Geropon SC / 213, Supragil MNS / 90, Supragil GN, Soprophore FL, SoprophorO FLK,

Soprophor 4D384.

The amount of dispersing agent in the solid phytosanitary composition is generally between 2 and 20% by weight, relative to the total weight of the

composition, preferably between 2 and 15% by weight, relative to the same reference.

It is advantageously between 2 and 10% by weight, relative to the weight

total of the solid phytosanitary composition.

The composition may likewise comprise additives common in the field, such as in particular disintegrating agents, anti-caking agents,

binding agents, inert fillers.

As examples of such compounds, mention may be made, inter alia, of starch, crosslinked polyvinylpyrrolidones, microcrystalline cellulose, crosslinked sodium carboxymethylcellulose, ammonium or sodium phosphates, sodium carbonate or bicarbonate, sodium acetate, sodium metasilicate, magnesium, zinc or calcium sulphates, magnesium hydroxide, calcium chloride,

molecular sieves.

Generally, the total amount of additives of this type, if they are present, varies between 0.5 and 40% by weight relative to the total weight of the phytosanitary composition.

solid, preferably between 1 and 30% by weight relative to the same reference.

As inert fillers capable of being used in the plant protection compositions according to the invention, mention may be made, without however being limited to them, of soluble or partially soluble starch; bentonite; kaolin; diatomaceous earth; rattapulgite; zeolites; alkaline earth metal carbonate, silicates

(calcium, magnesium in particular); talc; mica; silicon dioxide; silico-

aluminates, alkali metal, alkaline earth metal or ammonium sulphates; oxides, hydroxides or sulphates of elements of columns IIA, IIIB of the periodic table

elements; carbon black, alone or in mixtures.

The method according to the invention will now be described.

In a first step, a suspension is prepared comprising at least one active material, at least one surfactant and at least one anti-foaming agent as defined.

before.

Advantageously, the suspension is an aqueous suspension.

The amount of water added is more particularly between 20 and 60% in

weight relative to the weight of said suspension.

The preparation of the suspension is carried out in a conventional manner in the

field. Thus, all the products can be brought into contact simultaneously.

The preparation of the suspension is generally carried out at a temperature

close to room temperature.

The second step of the process for preparing the solid phytosanitary composition according to the invention consists in grinding the suspension, so as to obtain a

particle size distribution of the particles forming the suspension, appropriate.

Conventionally, the grinding is carried out until an average size of the

particles of the order of 1 to 10 μm, preferably of the order of 1 to 4 μm.

The grinding operation takes place in any type of suitable equipment, such as

in ball mills.

It should be noted, and this represents a very important advantage of the present invention, that it is no longer necessary to add an anti-foaming agent once the grinding has been carried out.

The suspension obtained is then dried.

The drying takes place using conventional means. But preferably, said drying takes place by atomization, that is to say by spraying the suspension in a hot atmosphere (spray-drying). This warm atmosphere

is advantageously of the air.

The atomization can be carried out by means of any sprayer known per se, by

for example by a spray nozzle of the sprinkling head type or the like.

So-called turbine atomizers can also be used.

This drying can take place in co-current, against the current.

On the various spraying techniques likely to be used in the present process, reference may be made in particular to the basic work of MASTERS entitled "SPRAY-DRYINGn (second edition, 1976, Editions George

Godwin - London).

It will be noted that ron can also implement the atomization operation.

drying by means of a 'flash' reactor, for example of the type described in particular in

French patent applications Nos. 2 257 326, 2 419 754 and 2 431 321.

By way of illustration, the gas inlet temperature during drying (whatever

either the method chosen) is between 130 and 250 C.

Obviously, the temperature to which the active material is subjected during

drying remains below the degradation temperature of said active material.

At the end of this drying operation, the solid phytosanitary composition according to the invention is obtained. It conventionally has an average particle size

of the order of 400 μm.

The solid phytosanitary composition obtained according to the process in accordance with the invention, more particularly in the form of a dispersible granule, has low foaming properties, when it is diluted or dispersed at the time of its use.

In addition, it retains such properties after storage.

A concrete but nonlimiting example of the invention will now be presented.

EXAMPLE

The following compositions are prepared: compounds comparative invention * tap water 225 g 225 g * Rhodorsilc 471 (Rhodia) 1.375 g

Brookfield viscosity 20 Pa.s.

* Rhodacal & DS / 10 (Rhodia) 11 9 11 g * Geropon SC213 (Rhodia) 22 q 22 g * Sodium lignosulfonate 22 g 22 g (Borresperse - Borregard) * Kaolin (Argirecg B24 - Blancs Minerals de Paris) 6.875 g 6.875 q * Isoproturon 211.8 g211.8 q

1 / preparation of the suspension.

In a beaker, with stirring with a deflocculating paddle of 65 mm in diameter), we

add all of the components in the order listed above.

then homogenized for 2 minutes at 6000 revolutions / minute, with UltraTurrax.

The mixture quickly demixes (brown liquid, beige solid).

2 / Grinding of the suspension A grinding is then carried out with Minimotormill (grinder comprising 190 ml of

glass beads (diameter 0.8-1.2 mm)).

One grinds at 1500 revolutions / minute and three grinds at 2000 revolutions / minute. 3 / Atomization / Drying of the suspension Atomization conditions: Atomizer inlet temperature: 145 C Atomizer outlet temperature: 135 C Nozzle air flow: 900 I / h Nozzle air pressure: 0.2 bar

Drying takes place in an Aeromatic fluid bed for 30 minutes at 60 C.

A composition is obtained in the form of granules.

4 / Foam persistence test before and after aging Part of the powder obtained previously was treated for 15 days at

54 C (simulation of storage conditions).

The foam persistence test was carried out as follows, with CIPAC 500 ppm water: Pour 100 ml of water into a test tube and introduce 2 g of

product to be tested, before plugging the test piece.

a Perform 30 complete retrouements, leaving each

turning the air bubble back up to the upper part.

a Unblock the test tube and start the stopwatch.

Measure volumes of foams at 0, 1, 5, 10, 20 and 30 mns.

The results are collated in the following table: volumes of foam Initial time (ml) (mirnutes) after storage comparative invention invention

0 35.4 40 33.7

1 22.5 37 21.4

16.9 37 16.3

14.6 34.5 14.6

3.4 29 3.4

2.2 i 26 t 2.2 It is observed that the composition has a significant defoaming activity, compared with the comparative composition devoid of antifoaming agent. In addition, the composition is stable after aging and the defoaming effect is retained.

Claims (12)

1. Process for preparing phytosanitary compositions in solid form, in which a suspension comprising at least one phytosanitary active material, at least one surfactant and at least one anti-foaming agent is carried out, followed by drying to obtain the phytosanitary composition in solid form, characterized in that the grinding is carried out with a suspension comprising at least one anti-foaming agent, chosen from silicone substances, having a Brookfield viscosity measured at 25 C, greater than or equal to 8 Pa.s 2. Method according to the preceding claim, characterized in that rl'on implements at least one anti-foam agent whose Brookfield viscosity is greater or equal to 10 Pa.s and preferably greater than or equal to 20 Pa.s. 3. Method according to any one of the preceding claims, characterized in that at least one anti-foaming agent chosen from silicone substances of the following formula is used: [(R1) 3SiO] - [R2R4SiO] x [(R3) 2SiOy - [(R1) 3SiO] in which: - the radicals R1, identical or different, substituted or not, represent a linear or branched alkyl, C1-Clo; a linear or branched alkenyl radical, C2-Clo; an aryl, alkyl-aryl, aryl-alkyl, aryl-alkenyl, alkenyl-aryl, C5-Clo radical for the aryl part and C1-C4 for the alkyl or alkenyl part, or a hydroxyl; 2-5; - the radicals R2, R3, R4, substituted or not, identical or different, represent a linear or branched alkyl, C1-Co10; an alkenyl radical, linear or branched, C2-C10; an aryl, alkyl-aryl, aryl-alkyl, aryl-alkenyl, alkenyl-aryl radical, at C5-Co10 for the aryl part and at C1-C4 for the aikyl or alkenyl part; - x and y represent average numbers of units chosen to ensure a Brookfield viscosity greater than or equal to 8 Pa.s, more particularly greater or equal to 10 Pa.s, preferably greater than or equal to 20 Pa.s. 4. Method according to the preceding claim, characterized in that one implements at least one anti-foaming agent whose radicals R1, identical or different, -35 represent methyl, ethyl, vinyl, phenyl, hydroxyl radicals; the radicals R2, R3, R4, identical or different, represent methyl radicals, ethyls, vinyls, phenyls. 5. Method according to any one of the preceding claims, characterized in which is used a total amount of anti-foaming agent representing 0.1 to 2% by weight relative to the total weight of the plant protection composition in solid form. 6. Method according to any one of the preceding claims, characterized in which ron uses at least one anti-foaming agent in the form of a compound. 7. Method according to the preceding claim, characterized in that the compound comprises at least one mineral filler chosen from precipitated silica, calcined silica, optionally having undergone a surface treatment aimed at hydrophobizing it, quartz, calcined clays, or even diatomaceous earths, oxides, hydroxides or sulphates of elements from columns IIA, IIIB of the periodic table elements, mica, gypsum, alone or in mixtures. 8. Method according to any one of the preceding claims, characterized in that at least one anti-foaming agent is used in the form of an emulsion. 9. Method according to any one of the preceding claims, characterized in that rl'on uses an amount of active material corresponding to 50 to 95% by weight relative to the total weight of the solid phytosanitary composition. 10. Method according to any one of the preceding claims, characterized in that your aforementioned suspension is an aqueous suspension. 11. Method according to the preceding claim, characterized in that the water content of the suspension represents 20 to 60% by weight relative to the total weight of the suspension. 12. Method according to any one of the preceding claims, characterized in what rl'on carries out spray drying.