LU84274A1 - PHYTOSANITARY COMPOSITIONS IN THE FORM OF GRANULES - Google Patents

Description

J - ♦ * \

The present invention relates to bioactive compositions consisting of effervescent granules containing a herbicide or acid growth regulator, an alkali carbonate or bicarbonate, and optionally additives such as mold release agents, binding agents and / or fillers.

We know the herbicide acifluorfen-salt oe sodium, marketed under the brands of Tackle and Blazer and constituted this 5- j_2-chloro-4- (trifluoromethyl) phenoxy] 10 -2-nitrobenzoate sodium; The acifluorfen is therefore 5- [2-chloro-4- (trifluoromethyl) phenoxyJ -2-nitro benzoic acid.

In the present description, the compounds are designated under their chemical name according to the French nomenclature, however the figures indicating the position of the killing substances are placed before the latter in accordance with the Anglo-Saxon nomenclature.

The formulations marketed for sodium acifluor-fen-salt are compositions comprising as main constituents of water (76%) and only about 24% of herbicide.

An object of the invention is to produce dry herbicidal compositions, easily dispersible in water and which contain a fairly high concentration of active herbicidal material.

On this point, it should be noted that since the acifluorfen-sodium salt is hygroscopic, it is not in itself a commercially suitable herbicidal concentrate.

Another object of the invention is to provide herbicide compositions which are not in powder form. In fact, people who apply pesticide products are turning away more and more from compositions in powder form because of the nuisance and inconvenience in handling the powders (need for a mask, soiling, etc.).

In addition, various kinds of pesticide granules are readily known in water, well known in particular; r i 2 called self-dispersible granules (in English "dry flowables"). In particular, effervescent granules have been proposed (French patents 2,290,844 and English patents 847,370), these granules comprising at least three essential constituents: the active material, the carbonate and an acid capable of reacting with the carbonate.

Another object of the invention is to provide herbicide compositions as simple as possible and containing a high content of active material.

Another object of the invention is to provide dry herbicidal compositions which can easily use active materials such as acifluorfen-sodium salt.

It has now been found that these various aims can be achieved by the compositions according to the invention.

The subject of the invention is therefore pesticidal, bioactive, and more particularly herbicide compositions, in the form of water-soluble granules, said granules comprising 50 to 90% in poias of a herbicide (or growth regulator). acice and about 10 to 40% of an alkali metal carbonate or bicarbonate, in particular potassium or preferably sodium. The amount of active acid material is preferably between 60 and 75%. The compositions according to the invention also optionally contain 0 to 10% of impurities of the herbicidal acid (isomers or by-products of manufacture).

It should be understood that the term granules should not be taken in a limited sense, and that it includes any other similar form such as grains, lozenges, tablets.

Generally, these granules have at least one dimension between 0.1 and 50 mm, preferably between 0.3 and 3 mm.

The relative amount of herbicidal active ingredient relative to the carbonate is such that the molar ratio 3 carbonate or bicarbonate / acid active ingredient is between 1 and 3, preferably between 1.3 and ?.

The compositions according to the invention may contain minor amounts (for example 0.1 to 10%) of other 3 additives such as lubricants or release agents (for example 0.05 to 1% of aluminum stearate, or less), stabilizers, binders, agents promoting grain cohesion (for example urea or cellulose derivatives), agents promoting disintegration.

The compositions according to the invention may also contain other additives useful for the pesti-cioe application considered. Thus, it may be necessary to add surfactants or wetting or dispersing agents or any other product capable of promoting the penetration of the active ingredient into the plant.

These surfactants can be emulsifying, dispersing or wetting agents of ionic or nonionic type or a mixture of such surfactants. Mention may be made, for example, of salts of polyacrylic acids, salts of lignosulfonic acids, polycondensates of ethylene oxide on fatty alcohols or on fatty acids or on fatty amines, substituted phenols (in particular alkylphenols or arylphenols), salts of sulfosuccinic acid esters, derivatives of taurine (in particular alkyltaurates), phosphoric esters of polyoxyethylated alcohols or phenols, esters of fatty acids and of polyols ; derivatives with sulphate, sulphonate, phosphate functions of the above compounds.

Preferably, in the compositions according to the invention, the grains are separated from each other and their mass can flow when poured.

According to an advantageous variant, the compositions of the invention contain no inert filler, in particular no inert filler insoluble in water.

Acifluorfen is the active ingredient which is particularly suitable for the invention, but it is also possible to use -> "" 4 le 5 - [_ 2-chloro-4- (trifluoromethyl) phenoxy J -2-nitro-N-mé thanesulfonyl-benzamide, 2,4-dichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid, 1-naphthalene acetic acid (as growth regulator), methyl paraaminophenylsulfonylcarbamate.

The granules according to the present invention can be made by compression (for example using a press or a compactor) of the constituents so as to obtain a tablet, then by granulation of the compact material obtained.

Obtaining ready-to-use slurry (solution or suspension) from the granules according to the invention is carried out simply by putting said granules in water in an amount corresponding to the desired concentration 13 for the active material.

The C02 released during effervescence causes rapid stirring of the solution; this stirring accelerates the dissolution of the ingredients in water and the salification of the acid; moreover the use of an acid in the formulation makes it possible to incorporate into the composition a higher content of active material than when the salt is added separately: this is a particularly advantageous advantage in the phytosanitary field where it is desirable to handle the least amount of products possible.

'23 The following examples, given without limitation, illustrate the invention and show how it can be implemented.

Example 1:

We mix: 30 - 7.23g of acifluorfen of purity 96¾ - 1.12g of anhydrous sodium carbonate - 0.01g of aluminum stearate.

The whole is ground in a glass ball mill comprising a single point of glass balls of 5 mm to 35 diameter. The mixture is then sieved and then compressed. The pellets obtained are lightly crushed in a 5% mortar and then pounded, sieved and the fraction is kept from 20 to 60 mesh (American standard sieves, 0.25-0.84mm).

By adding these granules to water, there is effervescence and dissolution, a clear solution-5 tion is obtained ready for spraying, except that it comprises in suspension particles of aluminum stearate.

*

The mixture contains 83% of herbicidal acid equivalent to 88% of the salt.

Example 2: 10 The following are mixed: - 7.22 g of acifluorfen (purity 96%) - 1.85 g of sodium bicarbonate - 0.01 g of aluminum stearate.

The mixture is treated as in Example 1. When water Gn is added to oe, results equivalent to those of Example 1 are obtained.

The mixture contains 76.4% herbicidal acid equivalent to 61% salt.

Example 3: 20 The following are mixed: - 74.9 g of acifluorfen of 80% purity - 25 g of anhydrous sodium carbonate - 0.1 g Ge aluminum stearate.

The whole is finely ground in a mechanical mill to obtain particles of 3 to 50 microns.

The mixture thus obtained is compressed under a pressure of 20 bars by a tablet making machine. The pellets obtained are crushed, then sieved so as to retain the grains of size 20 to 60 mesh (0.25 to 30 0.84 mm). These grains contain about 60% acifluorfen equivalent to 63.6% of its sodium salt.

These granules added to 4pau disintegrate with departure of this carbon dioxide and formation of the sodium salt of the acifluorfen-sodium salt, as in the previous examples.

* "6

Example 4: a mixture: - 63 g of acifluorfen of 80% purity - 25 g of anhydrous sodium carbonate 5 - 0.1 g of aluminum stearate.

The whole is ground as in Example 3.

The mixture obtained is compressed under a pressure of 5 bars by a tablet making machine. The pellets obtained are crushed and then sieved so as to retain the grains of size 15 to 30 mesh (0.5 to 1.2 mm). These grains contain 57.2% acifluorfen equivalent to 60% of its sodium salt; when put in water, they disintegrate perfectly and give an aqueous solution of the herbicide acifluorfen-sodium salt.

15 Example 5:

The procedure is as in Example 3 but replacing the 25 g of carbonate with 18 g of carbonate and 7 g of urea.

Granules of similar size and perfectly satisfactory as regards their disintegration in water are obtained.

Example 6:

Example 3 is repeated successively with 5- | 2-chloro-4- (trifluoromethyl) phenoxyj -2-nitro-N-methane-sultonyl-benzamide, 2,4-dichlorophenoxyacetic acid, 2- acid methyl-4-chlorophenoxyacetic and 1-naphthalene acetic acid.

• Satis granules are obtained in the same way, making and dissociating well in water.

4

Claims (10)

1. Bioactive compositions in the form of water-soluble granules, the said granules being characterized in that they comprise 50 to 90% of a herbicidal acid or growth regulator as well as 10 to 40% of carbonate or alkaline bicarbonate and possibly 0 to 10% of impurities <of the herbicidal acid. 2. Compositions according to claim 1, characterized in that the active material is herbicide. 3. Composition according to one of claims 1 or 2 characterized in that the alkali carbonate or bicarbonate is a sodium carbonate or bicarbonate. 4. Compositions according to one of claims 1 to 3 carac-15 terized in that they contain 60 to 75% of acidic herbicide. 5. Compositions according to one of claims 1 to 4, characterized in that the carbonate or bicarbonate / acid molar ratio is between 1 and 3, preferably between 1.3 and 2. 6. Compositions according to one of claims 1 to 5 characterized in that the granules are separated from each other and that their assembly is able to flow and that they do not contain an inert filler insoluble in water. »25 7) Composition according to one of claims 1 to 6 charac terized in that they contain 0.1 to 10% of an additive 'such as release agent, agent promoting disintegration, surfactant. 8. Compositions according to one of claims 1 to 7 carac-30 terized in that they contain 0.05 to 1% of aluminum stearate. 9. Compositions according to one of Claims 1 to 8, characterized in that the herbicide is acifluorfen. -1 8 "* 10. Compositions according to one of claims 1 to 8 characterized in that the acid active material is chosen from the group consisting of 5- [2-chloro-4- (trifluoro-methyl) phenoxyj-2-nitrc-N- methane sulfonylbenzamide, 2,4-dichlorophenoxyacetic acid, 1-naphthalene-acetic acid. AT " &