PT88056B - METHOD FOR THE PREPARATION OF PESTICIDE FORMULATIONS WITH WATER HAVING AN AVERAGE SIZE OF PARTICLE LESS THAN 200 NM AND METHOD FOR THEIR USE - Google Patents

Abstract

Water-miscible compsns. with an av. particle size (i.e. droplet size of dispersed phase) of up to 200 nm comprise water, oil, a surfactant and a cosurfactant with an HLB below 12.

Description

PROCESS FOR THE PREPARATION OF CHEMICAL FORMULATIONS

This invention relates to chemical formulations that are useful as water-miscible preparations of compounds that are normally considered to be insoluble in water and their use as pesticidal formulations.

Some of the most useful compounds in industry and agriculture are not soluble in water. This fact often prevents or reduces its use, particularly when it is desirable to apply the compound in solution. Although the compound can be very soluble in organic solvents, its use in large quantities is not always desirable from an economic or environmental point of view.

Such a group of compounds comprises pesticides, for example, pyrethroid pesticides, which are widely used commercially, either in the form of:

The. agrochemical concentrates of 5 g / 1- 500 g / 1 to be used after dilution in water; or in the form of

B. formulations of 0.1 g / 1 -1.0 g / 1 ready to use (p a u) in public health areas.

Typical solvents employed in these systems include hydrocarbons, such as, xylene, aromatic heavy naphtha, kerosene and various paraffins or alkanes.

A synthetic pyrethroid is deltamethrin, which is the common name for 3- (2,2-dibromoethyl) -2,2-dimethylcyclopropenoic acid carboxylic acid (3-phenoxyphenyl) methyl. Deltamethrin is a potent synthetic pyrethroid pesticide whose preparation of the racemic mixture is described in DE-A-4-2439177. Delmatrine is insoluble in water, but it is soluble in organic solvents, such as ethanol, acetone, dioxane, xylene and certain petroleum fractions.

Other synthetic pyrethroids include cyano (3-phenoxyphenyl) methyl cypermethrin (3- (2,2-dichlorophenyl) 2,2-dimethylcyclopropene-carboxylic permethrin (3- (2, 2, 2-dichloroethyl) -2,2-dimethylcyclopropenecarboxylic acid and phenvalerate (4-chloro-alpha- (1-methylethyl) -benzenoacetic acid (3-phenoxyphenyl) methyl ester. Cypermethrin can be prepared as described in DE- A-2326077, permethrin can be prepared as described in DE-A-2437882 and DE-A-2544150, and fenva lerate can be prepared as described in DE-A-2335341. Other pesticides include non-insecticides and pyrethroids (such as organophosphorus compounds) and herbicides and fungicides Organophosphorus compounds include chlorpyrites (0, 0_ -diethyl- £ -3,5,6-trichloro-2-pyridyl phosphorothioate), chlorpyrifos-methyl ( 0_, 0_-dimethyl-0_-3,5,6-trichloro-2-pyridyl phosphorothioate), phenothromion (0_, 0_-dimethyl-0_-4-nitro-m-tolyl phosphor rotioate) and pyrimiphos-methyl (0_-2-diethylamino-6-methylpyrimidin-4-yl-0.0-dimethyl phosphorothioate).

The present invention, in general, is directed to formulating water-insoluble, oil-soluble substances in water in the form of small particles, whose average particle size Z is less than 200 nm. The average size Z can be defined as the model medium free from light scattering. Such formulations include microemulsions, micellar solutions and molecular solutions.

Microemulsions are known in themselves. They are one of three identified types of dispersion (as distinct from a molecular solution) of oil, water and surfactant.

(the term oil is used in this specification to mean any non-aqueous solvent, in which a substance of interest is soluble and which is immiscible in water). These three

-5 types of dispersion are:

microemulsions, micellar solutions and normal (or macro emulsions) emulsions.

Macroemulsions appear white or opaque and are characterized by their properties in separating in their two original liquid phases at rest; the average particle diameter will, in general, be greater than 200 nm. Microemulsions and micellar solutions are translucent and do not separate. Microemulsions can be considered as having average droplet diameters or particle) from 10 to 200 nm, micellar solutions) as having average particle diameters from 2 'nm to 10 nm and molecular solutions as having mean particle diameters smaller than 2 nm. A recent sample suggests, however, that microemulsions with droplet diameters below 10 nm are possible.

Micelles occur when surfactants form large aggregates in water, when their concentration is greater than the critical micelle concentration (e m c); there is a sudden transition in the physical properties of such solutions to this concentration. In contrast, the physical properties. of surfactant solutions in non-aqueous solvents gradually change as the concentration increases. This is due to the fact that small aggregates are stable in non-aqueous solvents (for example, hydrocarbons) but are not in aqueous media, while the reverse is true for relatively large aggregates. Both spherical and cylindrical types of micelles have been recognized. Both of these types include aggregates of surfactant molecules, in which the hydrophilic tails point towards a nucleus, given that the heads hi. drophilic are directed externally.

Micellar solutions are observed when water is added to a solution of surfactant in oil or when oil is added to a solution of surfactant in water. Oil and water, which are practically immiscible in themselves meq

they can be solubilized with each other. When oil is solubilized in water, the oil molecules are incorporated between the chains of the surfactant molecules in the micelles: the solubilization can therefore be above the cmc. When water in oil is solubilized, it facilitates the aggregation of surfactant molecules in the form of inverted dilated micelles, in which the polar head groups are soaked in water. Such systems are considered as one-phase systems, and the groups are spherical or cylindrical.

Now returning to microemulsions, when a co-surfactant, such as an alcohol with a medium chain extension is added to a mixture containing oil, water and surfactant, the solubilized (oil or water) can form a nucleus surrounded by a layer of molecules surfactant and co-surfactant. The globules of oil in water or water in oil are almost all the same size, being smaller than 200 nm (and possibly in the range 10 to 100 nm).

As with macroemulsions, microemulsions can be of the water in oil (w / o) or oil in water (w / o) type and can be inverted from one to the other.

It is in the area of inversion that microemulsions exhibit peculiar properties. Starting from fluid w / o microemulsions as water is added, they pass through a viscoelastic gel zone and as more water is added, they are inverted into a fluid o / w microemulsion. This process is reversible and the viscoelastic gel zone (which can be almost solid) comprises a hexagonal system of water cylinders adjacent to the w / o mat and a lamellar phase of bimolecular leaflets adjacent to the o / w stage. These phases of the gel step are liquid crystalline phases.

Microemulsions have a number of physical properties that can be considered, either alone or together, as a characteristic. One of the properties is the way they scatter light. Microemulsions are blue in reflected light and orange / red in still light

- allowed due to the Tyndall effect. Its molecules or components disperse light. Particles that are large compared to the extent of the light beam (white light can be said to have a radius span of 560 nm for the present purposes) reflect and refract on a regular basis and thus appear white. In comparison, the small particles scatter light in all directions and for this scattered light is a polarized plane. When the droplets of an emulsion are less than lambda / 4 in diameter, white light may pass through the dispersion and become translucent (or opalescent). Depending on the relative refractive indexes of the components, such systems become transparent (or very translucent). Rheology can also be used as a feature. When the dispersed aggregates are different from the spherical ones, they offer greater resistance to flow, and this can usually be detected in the form of a sudden and sudden increase in viscosity. In the case of microemulsions, the formation of the viscoelastic gel zone corresponds to the formation of non-spheroidal aggregates.

Sedimentation variations can be used for differentials between macroemulsions and microemulsions. Five minutes in a centrifuge at 100 to 500 x g will normally give you a cream or sediment from a macroemu). are. Generally speaking, microemulsions will not separate under such conditions.

Birefringence can also be identified as a characteristic of microemulsions. When very small aggregates are not isotropic, their dispersions become doubly refractive when they are stirred or allowed to flow. After the study between crossed filters (PC), the illuminated field will appear illuminated in brightly colored sea patterns. This is due to the dispersion and repolarization of polarized light.

Conductivity can be used

-8da to distinguish between continuous oil microemulsions and continuous oil micellar solutions. For a microemulsion, varying the conductivity as a function of (water volume) / (oil volume) reveals that there is no significant change as water is added close to the viscoelastic gel zone, whereas for micellar solutions, as water is added, there is a constant increase in conductivity. In both cases, the actual variation is anything more complex than this simple comparison, which should nevertheless serve as a useful guide. Conductivity can be measured, for example, on a PII-20 Digital Analyzer Apparatus (Analytical Suppliers, Derby).

One of the best ways to differentiate between formulations according to the invention and macroemulsions (and between microemulsions, micellar solutions and molecular solutions) is based on the particle or droplet size (usually measured in the form of averages). The average particle size or droplet can be measured with a laser particle grinder, such as the MALVERN 2c AUTO RECTIFIER (Malvern Instruments, Malvern, Hereford & Worcester), using glass cells as sample containers .

Other techniques can be used to determine additional or alternative features of formulations of this invention.

These include X-ray studies, electron microxopia, light scattering depolarization and r mn. In general, rmn measurements are used to clarify theoretical issues taking into account the state or location of the molecules in microemulsions. The width of the line in relation to the protons in molecules can indicate freedom of the molecules in relation to the thermal movement, indicating the widening of the line greater restriction of movement. The chemical change of water is different when it is distributed in spheres or in cylindrical or lamellar micelles. Further studies are possible using rmn,

in addition.

US-A-4567161 discloses concentrations of active liquid ingredient for the preparation of microemulsions. It is established that microemulsions are oil-in-water microemulsions. Coemulsifiers are a particular class of glycerin esters having EHL (hydrophilic / lipophilic balance) values between 12 and 18. US-A-4567161 formulations are said to have special significance for active pharmaceutical substances. However, the active ingredient can be a number of other substances, including herbicides (some of which are specified), fungicides, insecticides, acaricides, nematocides or plant growth regulators. No specific fungicides, insecticides, acaricides, nematocides or growth regulators are revealed or suggested.

It has now been discovered that by choosing coemulsifiers that have particular EHL values, it is possible to formulate microemulsions, which can invert having w / o formulations into w / o formulations, thus making their use much more flexible. It is also possible to formulate molecular solutions or micellar solutions, which form microemulsions in dilution with water. In addition, it has been found that certain pesticide formulations, such as pyrethroids (for example, deltamethrin, cypermethrin or permethrin) show marked biological activity.

According to the first aspect of the present invention, a water miscible formulation is provided, the average particle size of which is at most 200 nm, the formulation comprising water, oil, a surfactant and a factoring cos having an EHL less than 12.

As previously indicated, if the formulation is a microemulsion, the microemulsion will, in general, be clear or translucent, except in the vis coelastic gel phase. Micellar solutions and molecular solutions can

-10 must additionally be clear.

The water can be tap water although distilled water can be used. The amount of water in the microemulsion will depend on many factors but typically pa. w / w microemulsions will be 20 to 70% w / v and for w / o microemulsions it will be 40 to 95% w / v. In practice, it can be beneficial, although not essential, some hardness in the water. Hardness between 100 and 200 ppm (as CaCOg) may be appropriate, particularly around 150 ppm or 160 ppm.

As previously established, the oil need not merely be an oil in the sense of a fraction of petroleum, although such oils are included; the term oil is used to mean any non-aqueous solvent in which an interejeb substance is soluble and which is immiscible in water; alternatively, the substance of interest may itself be oil. Having said that, the oil can be animal, vegetable, mineral or silicone or any other organic solvent that is immiscible in water, such as an optionally halogenated hydrocarbon. The hydrocarbon can be aliphatic or aromatic or have both aliphatic and aromatic fractions. Typical solvents include xylene, naphthalene, kerosene, isoparaffins and halogenated hydrocarbons.

The surfactant can be any typical emulsifier as described in most macroemulsion systems. The surfactant can be anionic, cationic, zwitterionic or nonionic. Anionic surfactants are most often used. Suitable anionic surfactants include sulfates, sulfonates and hydrocarbon sulfamates, in particular compounds in which the hydrocarbon moiety is in an alkyl or alkylaryl group. Soaps (hydrocarbyl carboxylates) can also be used, as well as sulfocarboxylic acids, such as sulfosuccinic acid. Examples of specific anionic detergents that can be used include alkyl benzene sulfonates and sulfonic acids, such as benzene Cg _to C- ^ θ alkyl sulfonates and sulfon /

-Oils including dodecyl benzene sulfonic acid (a predominantly branched chain mixture of such compounds, is sold under the brand name NANSASSA).

The selection of a suitable surfactant can be made by anyone skilled in the art. As an indicator principle, it should be noted that it is highly preferable to pair, in a chemical sense, the structure of the surfactant with the structure of the oil. For example, if the oil is aromatic, such as xylene or naphthalene, it is preferable to use a surfactant having an aromatic fraction for example, an alkyl benzene sulfonate or an alkyl naphthalene sulfonate. If the oil is aliphatic, an aliphatic surfactant, such as an alkyl sulfonate or a dialkyl sulfosuccinate (such as dioctyl sulfosuccinate) or a soap is preferable. Another factor that determines the choice of surfactant is the type of microemulsion (a / o or o / a) to be produced.

Low EHL surfactants (for example, having an EHL of 4 to 9, particularly 4 to 7) tend to stabilize a / o microemulsions and should therefore preferably be used for a / o microemulsions o and high EHL surfactants (for example, having an EHL of 9 to 20, particularly 9 to 20) tend to stabilize o / w microemulsions and should therefore be used for o / w microemulsions. EHL values can be measured using standard techniques.

After the initial selection has been made (for example, on the basis of EHL), further selection of the surfactant can be achieved by comparing the hydrophobic portion of the surfactant with the oil structure, as discussed earlier. Polar groups also play an important role in the surfactant and must be considered in the rigging process.

An alternative or additional surfactant selection system is based on the inversion phase temperature (TFI) and can therefore be referred to as the TFI system. This system is based on the temperature at which a sur-12factant causes an o / a emulsion to be inverted into a w / o emulin. It provides information regarding the types of oils, the phase-volume relationship and the concentration of surfactant that could be used. This system is established on the proposal that the EHL of a nonionic surfactant changes with temperature; the inversion of a type of emulsion occurs when the hydrophilic and lipophilic trends of the surfactant are precisely in balance. There are no forms of emulsion at this temperature. Nonionic surfactant stabilized emulsions tend to be of the o / a type at low temperatures and of the w / o types at high temperatures. From the microemulsion point of view, the TFI system has a useful feature, in that it can reflect light on the preferred chemical type of surfactant to match a given oil.

Water-miscible formulations according to the first aspect of the invention include a co-surfactant having an EHL less than 12. Typically, two classes of co-surfactants are preferred to employ, although others can be used. Aliphatic alcohols (particularly primary aliphatic alcohols) constitute a preferred first class. They can have a carbon content of 5 to 12 or more carbon atoms. Lower homologues (for example, Cg to C / alcohols are used to stabilize certain formulations, including w / o microemulsions and previous Cg alcohols (optionally including C _Q ) tend to be used to stabilize other formulations, including o / microemulsions The.

Nonionic surfactants form a more versatile group of co-surfactants. They can be balanced with the primary surfactant to give systems that are stable as micellar solutions and as both w / o and w / o microemulsions. A full range of nonionics can be used, including chain copolymers of ethylene oxide propylene oxide (as typified by BASF's range of PLURONIC PE or PLURIOL PE) and alcohol ethoxylates (as typi.

-13 (made by Shell's DOBANOL range)

EHL of the co-surfactant can be less than 10 or even less than 5. For example, a non-ionic co-surfactant is the ethylene oxide propylene oxide block copolymer containing 10% ethylene oxide, sold under the PLURONIC PE 6100 or PLURIOL PE 6100, which has an EHL of 3.0 Other EHL values suitable for co-surfactants are less than 3, for example, about 2 or even about 1.

It is possible to choose an appropriate co-surfactant to be formulated with a surfactant and other microemulsion components according to the inventions, for anyone skilled in the art. The methods previously discussed in relation to the choice of surfactant can also support the choice of co-surfactant. In addition or alternatively, the technique of partitioning the co-surfactant can assist in the preparation of microemulsions. This approximation is based on the premise that the responsible condition pa. For spontaneous formation and stability of microemulsions, there is an interfacial tension of zero (or transiently negative) The total interfacial tension was given by the formula:

i = (o / a) =

Where total interfacial tension, interfacial tension before the addition of stabilizing agents and yy - two dimensional dispersing pressures in the monolayer of adsorbed species.

-14Fci, then, it was proposed that the initial zero or the negative value of the total interfacial tension was the result not so much of a high value of the two dimensional dispersing pressures but of the great depression in the value of (^ o / a) a - , where ((a) a) is the interfacial tension after the addition of stabilizing agents.

Since most microemulsions appear to form much more easily in the presence of a cosurfactant, which is oil soluble, it was assumed that this material itself is distributed between the oil phase and the interface and subsequently changed the composition of the oil so that its interfacial tension has been reduced to (^ o / a) a. This provides a formula with a useful aid to help match emulsifiers (surfactants and co-surfactants) to oils for microemulsification. From an economic point of view, it is certainly desirable to use only a minimum of co-surfactant, which is suitable for use in any formulation of the invention under consideration.

Using the technique of dividing the co-surfactant, it has been found that for any given surfactant, a short chain co-surfactant will tend to produce a w / o system, while a long chain co-surfactant will tend to stimulate a the. In the case of soaps, the largest size of the cation (hydrated), the most effective of that particular soap, will be in stimulating a microemulsion of o / a.

From the point of view of the present invention. so, it is secondary if, the zero interfacial argument as a prerequisite for microemulsion stability, is correct. The argument was given only to illustrate how the co-surfactant can be selected. It is accepted that the use of the film's balance equation is an oversimplification, however, from the practical point of view of the formulator, the expression (^ o / a) a can be valuable.

The relative proportions of the various ingredients of the formulations according to the present invention can vary widely. For w / o microemulsions, micellar solutions and molecular solutions, the general and preferred ranges of ingredients can be as follows:

Ingredient w / v in general oil (including dissolved substance if any) 20 to 50%

Surfactant

Co-surfactant

Water 20% to 20% to 70% w / v preferred 40% to 5% l to 5% to 70%

In general, the amounts of surfactant and co-surfactant should be kept as low as well. and the amount of water should be kept as high as possible. The above is always true with the proviso that the total number of parts as a percentage of the ingredients cannot exceed 100.

For o / w microemulsions, the general and preferred concentration ranges of the ingredients can be as follows:

Ingredient p / v in general p / v preferred Oil (including dissolved if any) 1 The 20% 1 The 10% Active surf 1 The 10% 1 The 5% Co-surfactant 1 The 10% 1 The 5% Water 40 The 9 5% 70 The 90%

Again, what has been said above is always true with the proviso that the total number of parts as a percentage of the ingredients cannot exceed 100.

A substance, insoluble in water, soluble in oil, which one wishes to formulate, can be dissolved in the oil, although it is clear that the oil itself may be the substance insoluble in water, soluble in oil. This substance of interest can be any that is convenient to be formulated in this way (including other solvents). As previously established, pesticides, such as synthetic pyrethroids and herbicides, are particular candidates for formulation by means of the present invention. In addition to synthetic pyrethroids, natural pyrethroids, organic phosphorus compounds and carbanates are other examples of pesticides useful in the present invention. Mixtures of pesticides (eg mixtures of pyrethroids or mixtures of pyrethroid (s) and organic phosphorus compound (s) may be particularly suitable for some applications. Cypermethrin is an example of a liquid that can function both as an oil and as a substance insoluble in water, soluble in oil.

-17 <1) | -H |

Therefore, according to the second aspect, a water-miscible formulation is provided, whose average particle size is at most 200 nm, including the formulation water, oil, a surfactant and a co-surfactant, in which either the The oil is a pesticide or the formulation comprises a pesticide dissolved in the oil. When the oil is a pesticide, the formulation may be free of an oily solvent for the pesticide.

It is preferable that the cosurfactant has an EHL, less than 12.

The pesticide can be pyrethroid or any other insecticide, acaricide, herbicide or fungicide. Other preferred features of this second aspect of the invention are such, as for the first aspect mutatis mutandis.

With microemulsions of water in oil, micellar solutions and molecular solutions, in general, it is possible to obtain a higher concentration of the substance of interest (for example deltamethrin or another synthetic pyrethroid or another pesticide). However, o / w formulations can give a perfectly suitable concentration for final use or even for diluting concentrates before use.

In principle, a. according to the invention can be made in a very simple way. Therefore, according to a third aspect of the present invention, a formulation according to the first or second aspect is prepared by mixing ingredients. Depending on the thermodynamic acceptance of the system, the ingredients will tend to form a microemulsion, micellar solution or molecular solution. In practice, however, kinetic considerations may require that, preferably, some agitation is used to aid mixing. Stirring can be done by magnetic or mechanical means or, in some cases, ultrasonic.

Once a desired and correctly balanced formulation has been achieved, it will be found that the order in which the ingredients are added is usually not critical. However, for w / o microemulsions, micellar solutions and molecular solutions, it is preferable to add the ingredients in a container in the following order:

1. Add the oil in a container

2. Add guaisguer additives, such as deltametr_i in the solid, dissolved in another oil.

3. Add the surfactant and co-surfactant and dissolve them in the oil.

4. Add water to give a clear formulation (for example, a w / o microemulsion).

Although it may be found that the previous procedure is suitable for o / w microemulsions, there is a possibility that after the addition of water, the system could move into the viscoelastic gel zone (which can be almost solid) and this could cause practical mixing problems. Consequently, the following procedure for the preparation of o / w microemulsions is preferable:

1. The oil is added to a container

2. Additives (such as solid deltamethrin) are dissolved in the oil.

3. The surfactant is added and dissolved in the oil

4. Water is added and stirred to give a homogeneous macroemulation.

5. The co-surfactant is added and the system is agitated to produce a clear o / w microemulsion.

Routine modifications can be made to these basic processes to adapt the system to be used, such as applying heat or changing the degree of agitation.

It has previously been established that preferred pyrethroid or other pesticide microemulsion formulations have been found to have increased pesticidal activity. Therefore, according to a fourth aspect of the present invention, a method for controlling pests is provided, the process comprising applying a pesticide to a formulation, the average particle size of which is at most 200 nm. A. formulation can be a microemulsion, a micellar solution and a molecular solution; the microemulsion can be an o / w or a / o formulation. Oil-in-water microemulsion formulations are preferred. The formulation will generally comprise water, a pesticidal oil, a surfactant and a co-surfactant preferably, having an EHL of less than 12. Pyroids or other pesticides formulated in this way can be used to control pests in an agricultural environment , for example, in a harvest field. Examples of crops include cereals, brassicas such as cabbages and fruit such as apples and pears. Pests can be insects or mites or can be aphids; pests can be in the form of larvae. Another application is in the storage of cereals in large quantities, where the pile grain is susceptible to a variety of pests. In particular, in hot climates, such as the southern United States and Australia, the lower grain-perforating weevil (Rhyzopertha dominica caused considerable economic loss and proved to be difficult to control using conventional formulations. Formulations according to with the invention are surprisingly effective in treating such pests, in particular, the formulations of the invention have high activity, surprising persistence and can allow precisely to control and even dose the pesticide on the material to be protected. in general, can be achieved

by means of the present invention.

The applications of such pyrethroid or other pesticide formulations (eg, organo phosphorus) are not confined to agriculture: public health formulations can be commercially important. The agricultural formulations according to the invention may have one more advantage, in that it used less potentially harmful solvent (such as, xylene) per dose than certain conventional formulations, so it poses less of a threat to the crop to be treated, for the manager and the environment in general.

In accordance with a fifth aspect of the invention, a method for controlling pests in stored cereals is provided, the method comprising applying a water miscible formulation to a pest lime (e.g. stored cereal or a stored cereal container). , whose average particle size is at most 200 nm, including the formulation water, oil, a surfactant, a cosurfactant, in which either the oil is a pesticide or the formulation comprises a pesticide dissolved in the oil.

Other preferred features of the fourth and fifth aspects are as in the first aspect mutatis mutandis.

The concentration of substance of interest (for example, deltamethrin) in the investment formulations can vary as little as 0.1 ppm, 0.01 g / 1 or 0.1 g / 1 to 100 or 200 g / 1 or more. High concentrations of pesticide can vary from 10 to 300 g / 1, for example, 25 to 200 g / 1, such as 25 or 100 g / 1. For agricultural use of deltamethrin or another pyrethroid pesticide, it can be verified that the final concentration of 10 to 50 g / 1 or 100 g / 1 is adequate. For public health or for use in stored cereals, it can be seen that a formulation containing 0, 1 ppm or 0.05 g / 1, for example, 0.1 g / 1 to 1 g / 1, is acceptable.

-210 invention will be illustrated by the following examples

EXAMPLE 1

A w / o microemulsion was created from the following ingredients:

Xylene / Deltamethrin Concentrate ^^ 200 ml / 1

Xylene 200 ml / 1 PLURIOL PE 6100 ⁽²⁾ 150 g / 1 NANSA SSA ⁽³⁾ 130 g / 1 Water (from tap) 345 g / 1

Grades:

(1) The concentrate contained 125 g / 1 of deltamethrin and gives a final concentration of 25 g / l (2) Mark in relation to the ethylene oxide propylene oxide block copolymer containing 10% ethylene oxide, nonionic surfactant-EHL 3.0, working as a co-surfactant.

(3) Brand in relation to dodecyl benzene sulfonic acid - predominantly simple chain (anionic surfactant).

One liter of the previous formulation was prepared by first adding 200 ml of xylene to a beaker. Then 200 ml of the xylene / deltamethrin concentrate was added to the same beaker. The surfactant and co-surfactant were then added and dissolved in the oil phase. Then, water was added, with stirring, to give a clear w / o microemulsion. The formula.

-22 was confirmed to be a microemulsion by conductivity measurements. The average particle size of a 1/400 dilution was measured by a laser particle size rectifier MALVERN SIZE 2C AUTORECTIFIER, 62.8 + 11.8 nm.

EXAMPLE 2

A formulation was prepared from the following ingredients:

Deltamethrin

Xylene

NANSA SSA (2)

Copolymer of propylene oxide / / ethylene oxide *

Water, 4 g / 1 25, 75 g / 1 g / 1, 2 g / 1 906 g / 1 * Co-surfactant: molar mass of the polypropylene oxide portion = 1750 g / mol; percentage of polyethylene oxide in total molecule = 10%

One liter of the previous formulation was prepared by first adding xylene to a beaker. Then, solid deltamethrin was added and dissolved in xylene. The NANSA SSA surfactant was then added and dissolved in the oil phase. Subsequently, water was added and the mixture was stirred to give a homogeneous macroemulsion. Finally, the co-surfactant (PLURIOL PE 6100) was added and the entire system was agitated to produce a clear formulation. The average pair size

-23 particle was measured by a laser particle size rectifier, MALVERN SIZE AUTORECTIFIER 2C, being 0.8 nm which indicates that the formulation is a molecular solution.

EXAMPLE 3

A formulation was prepared from the following ingredients:

Xylene / Cypermethrin 400 ml / 1 PLURIOL PE 6100 150 g / i NANSA SSA 130 g / i Water 345 g / i

note:

(1) 100 g of cypermethrin (technique) created for 400 ml with xylene (2) Brand in relation to dodecyl benzene sulfonic acid - predominantly simple chain (anionic surfactant).

20 g of cypermethrin was created to 80 ml with xylene, and the resulting mixture was placed in a 250 ml beaker. The PLURIOL PE 6100 surfactant and the NANSA SSA co-surfactant were then slowly dissolved therein and the appropriate amount of water (69.0 ml) was added slowly from a burette under agitation. The formulation was confirmed to be a micellar solution by conductivity measurements. The average particle size of a dilution was measured by a laser particle size rectifier,

Λ

-24 MALVERN SIZE AUTORECTIFIER 2C, 40.2 + 6.9 nm, revealing that the diluted formulation is a microemulsion.

EXAMPLE 4

A ready-to-use formulation was

. starting from following ingredients. (1 ) 8.0 ml / 1 KOTHRINE 50 Xylene 2.0 ml / 1 PLURONIC 1 PE 10 100 ⁽²¹ 9.0 g / 1 NANSA SSA 6.0 g / 1 Water 976.0 g / 1

Grades:

(1) A 50 g / 1 solution of deltamethrin in xylene (2) Marked in relation to a ethylene oxide chain copolymer of propylene oxide containing 10% ethylene oxide, EHL 3.0 nonionic surfactant, working as a co-surfactant.

K'OTHRINE and xylene were mis; and the surfactants were dissolved in them; then water was added from a burette under constant agitation. The ta. mean particle size was measured by a ta rectifier. particle laser, MALVERN SIZE AUTORECTIFIER 2C, 15.0 + 2.2 nm, revealing that the formulation is at the lower limit of the size for a microemulsion.

EXAMPLE 5

A ready-to-use formulation was created from the following ingredients:

KOTHRINE 50 ⁽¹⁾ 8.0 ml / 1

Xylene 2.0 ml / 1

PLUROMIC PE 10 100 ⁽²⁾ 12.0 g / 1

NANSA SSA 8.0 g / 1

Water 91 7.0 g / 1

Grades:

(1) A 50 g / 1 solution of deltamethrin in xylene (2) Marked over a ethylene oxide / propylene oxide chain copolymer containing 10% ethylene oxide, non-ionic EHL 3.0 surfactant working as a co-surfactant.

K'OTHRINE and xylene were placed in a beaker. To these, PLURIOL and NANSA were added; then it was mixed well. Water was added to this mixture under constant stirring. The average particle size was measured by a laser particle size rectifier, MALVERN SIZE AUTORECTIFIER 2C, with 4.1 + 1.4 nm, revealing that the formulation is a micellar solution.

-26EXAMPLE 6

A formulation was created

following ingredients; K'OTHRINE 50 ^1} 40, 0 ml / 1 NANSA SSA 34.2 g / i (2) PLURONIC PE 6200 ^k ' 41.8 g / i Filtered tap water 889 g / i

Grades:

(1) A 50 g / 1 solution of deltamethrin in xylene (2) Mark in relation to a ethylene oxide propylene oxide chain copolymer containing 20% ethylene oxide - nonionic surfactant, acting as a cosurfactant.

Ml of KOTHRINE, 34.2 g of NANSA SSA and 41.8 g of PLURIOL PE 6200 were placed in a beaker (cup) and then mixed with a shaker. Then, 889 g of water were added to this mixture under constant stirring. The average particle size was measured by a laser particle size rectifier, MALVERN SIZE AUTORECTIFIER 2C, Being 0.8 nm, revealed that the formulation is a molecular solution. An 8% dilution had an average particle size of 73.0 + 14.3 nm, measured in a similar manner, revealing that the diluted formulation is a microemulsion.

-27EXAMPLE 7

from the following ingredients:

Cypermethrin

Xylene

PLURIOL PE 8100 ⁽¹ NANSA SSA

Water

A formulation was created at par50 g / 1 38.5 g / 1

100 g / 1

53.8 g / 1 757.7 g / 1

note:

(1) Brand referring to the ethylene oxide propylene oxide chain copolymer containing 10% ethylene oxide (EHL = 2) - its non-ionic substance acting as a co-surfactant.

Cypermethrin was dissolved in xylene; to this, PLURIOL PE 8100 is NANSA SSA were added and mixed well. The water was added, slowly, under constant stirring until clear. The average particle size of a 1/400 dilution in water was measured by a laser particle size rectifier, SIZE AUTO-RECTOR NHO MALVERN 2C, Being 41.2 + 7.0 nm, revealing that the formulation is a microemulsion .

i

-28EXAMPLE 8

A formulation was created based on the following ingredients:

Cypermethrin 50 g / 1 PLURIOL PE 8100 ⁽¹ ' 130 g / i NANSA SSA 70 g / i Water 750 g / i

note:

(1) Mark referring to an ethylene oxide propylene oxide chain copolymer containing 10% ethylene oxide (EHL = 2) non-ionic surfactant working as a cosurfactant.

Cypermethrin was dissolved in PLURIOL PE 8100 and NANSA SSA. The water was added slowly under constant stirring until clear. The average particle size was measured by a laser particle size rectifier, MALVERN SIZE 2C AUTORECTIFIER, Sen from 7.8 + 1.6 nm, revealing that the formulation is a micellar solution. It is assumed that a diluting microemulsion would be formed.

-29EXAMPLE 9

A formulation was created based on the following ingredients:

Cypermethrin 95.6 g / 1 Xylene 36.8 g / 1 PLURIOL PE 8100 ^(1} 124.3 g / 1 NANSA SSA 66.9 g / 1 Water 676.4 g /

note:

(1) Mark referring to an ethylene oxide propylene oxide chain copolymer containing 10% ethylene oxide (E H L = 2) - non-ionic surfactant working as a co-surfactant.

Cypermethrin was dissolved added PLURIOL PE 8100 and NANSA water was added slowly under the clear. The average particle size% rectifier of MALVERN SIZE 2C, 40.6 + 7, in xylene. This was SSA and well mixed. The constant agitation until cuia was measured by a laser AUTORECTIFICADOR nm, revealing that the formulation is a microemulsion.

I

-30EXAMPLE 10

A formulation was created based on the following ingredients:

Cypermethrin 100 g / 1 PLURIOL PE 8100 ⁽¹⁵ 154 g / i NANSA SSA 83 g / i Water 663 g / i

note:

ethylene oxide (EHL = 2) cosurfactant.

(1 )

Mark referring to a propylene oxide chain copolymer containing 10% non-ionic surfactant oxide functioning as

Cypermethrin was dissolved 8100 and NANSA SSA. The water was added constant slowing until it was clear. The average size was measured by a pair size rectifier, MALVERN SIZE 2C AUTORECTIFIER, which reveals that the formulation is a microemulsion.

in PLURIOL PE mind under laser particle agi 18.1 + 3.9 nm

EXAMPLE 11

Following the general procedure of Example 1, a microemulsion of fervalerate was prepared at a final concentration of 100 g / 1.

EXAMPLE 12

A formulation was created based on the following ingredients:

Fenitrotiono 175 g / i Deltamethrin 25 g / i Xylene 180 g / i PLURIOL PE 8100 150 g / i NANSA SSA 100 g / i Water 400 g / i

fenitrothion and deltamethrin were dissolved in xylene; to the resulting solution, were added. PLURIOL PE 8100 and NANSA SSA were stirred. Then, the water was added slowly under constant stirring until clear. The average particle size of a 1/400 dilution in water was measured by a laser particle size rectifier, MALVERN SIZE 2C AUTORECTIFIER, Being 41.5 + H, 4 nm, revealing that the diluted formulation is a micro emulsion .

EXAMPLE 13

A formulation was created from the following ingredients:

Chlorpyrifos-methyl

Deltamethrin

175 g / 1 25 g / 1

Xylene 180 g / i PLURIOL PE 8100 150 g / L NANSA SSA 100 g / i Water 400 g / i

Chlorpyrifos-methyl and delta, metrine were dissolved in xylene; to the resulting solution, PLURIOL PE 8100 and NANSA SSA were added under stirring. Then, the water was added slowly under constant stirring until it became clear. The average particle size of a 1/400 dilution in water, was measured by a laser particle size rectifier, MALVERN SIZE AUTORECTIFIER 2C, Being about 40 nm, revealing that the diluted formulation is a microemulsion.

EXAMPLE 14

A formulation was created from the following ingredients:

Fenitrotiono 150 g / 1 Cypermethrin 50 g / i Xylene 180 g / i PLURIOL PE 8100 150 g / i NANSA SSA 100 g / i Water 40 0 g / i

-33 Fenitrothion and cypermethrin were dissolved in xylene; PLURIOL PE 8100 and NANSA SSA were added to the resulting solution with stirring. Then the water was added slowly under constant stirring until it was clear. The average particle size of a 1/400 dilution in water can be measured by a laser particle size rectifier, MALVERN SIZE AUTORECTIFIER 2C, Being about 40 nm, revealing that the diluted formulation is a microemulsion.

EXAMPLE 15

A formulation was created from the following ingredients:

Chlorpyrifos-methyl 150 g / i Cypermethrin 50 g / i Xylene 180 g / i PLURIOL PE 8100 150 g / i NANSA SSA 100 g / i Water 400 g / i

chlorpyrifos-methyl and cipeir metrina were dissolved in xylene to the resulting solution, PLURIOL PE 8100 and NANSA SSA were added under stirring. Then, the water was added slowly under constant stirring until it was clear. The average particle size of a 1/400 dilution in water can be measured by a laser particle size rectifier, MALVERN SIZE AUTORECTIFIER 2C, Being about 40 nm, revealing that the diluted formulation is a microemulsion.

'- \

-34 EXAMPLE A

A microemulsion of deltamethrin, as prepared in Example 1, was used to treat a cabbage crop in southern Nottinghamshire, where most of the plants were infested with 2 to 4 small gray aphid colonies, with some caterpillars present. The atmospheric conditions were sunny and the temperature was 16 °.

The formulation of Example 1 was applied at rates of 50, 70, 150 and 450 mls / ha and compared to a control formulation (deltamethrin DECIS) of comparable concentration. The DECIS formulation was applied at rates of 50, 75 and 150 ml. These treatments together with the untreated control formulations are shown in Table 1. The word DECIS is a brand.

TABLE I

Treatment No.

Product

Not treated

Example 1 Example 1 Example 1 Example 1

DECIS

DECIS

DECIS

MlsVha Rate

150

50

150

-35Rate N was chosen as

150 mls / ha, that is, the maintenance rate normally used in a repeated application program. This rate was chosen to test products at lower than normal total effectiveness rates

Results were assessed by treating the number of live aphid colonies per plant after treatment. The test comprised four replications, each consisting of examining 25 plants. In other words, 100 plants per treatment were calculated. The number of colonies remaining, as well as the degree of control (percentage), of pests, compared to untreated plants, are shown in Table 2.

TABLE 2

Without treatment 1 2 3 4 5 6 7 8 Rate (mls / ha) 0 50 75 150 450 50 75 150 Rep 1 47.0 10 .0 6.0 6.0 4.0 28.0 19.0 11.0 Rep 2 33.0 14.0 13.0 7.0 0 28.0 17.0 14.0 Rep 3 34.0 17.0 8.0 5.0 3.0 20 .0 13.0 7.0 Rep 4 38.0 12.0 11.0 7.0 6.0 15.0 12.0 12.0 Total 152.0 53.0 38 .0 25.0 13.0 91.0 61.0 44.0 Middle 38 .0 13.3 9.5 6.3 3.3 22.8 15.3 11.0 % in ( sontrol 65.1 75.0 83.6 91.4 40 .1 59.9 71.1

Not treated

Minimum significant difference between media:

4.14 to 95% probability 5.65 to 99% probability 7.60 to 99.9% probability

-36The results can be analyzed as follows:

TABLE 3

Control rate (mis / ha)%

Example 1 DECIS

Example 1 / DECIS (%) improved: o

50 65.1 40, 1 162 62 75 75.0 59.9 125 25 150 83.6 71.1 117 17

In Table 3 and Figure 1, which graphically shows the percentage of control as a function of the application rate for the formulation of Example 1 and the formulation of DECIS, it can be seen that microemulsions according to the present invention are more active than conventional non-microemulsion formulations. The microemulsion of Example 1 shows improvements between 15 and 60% over the standardized formulation, depending on the rates used; and it seems to achieve commercial acceptability, that is, more than 70% control at about 60 mls / ha.

EXAMPLE Β

LD50 ^to P ^purple i ^< 3os of the microemulsions of Examples 1.3 and 11 against blowworm larvae were terminated by topical application of 1 microliter in various dilutions and were compared with the LD ^^ s of corresponding emulsifiable concentrates ( CES). The results are shown in Table 4:

TABLE 4

Active ingredient Approximate LDj-θ (mcg / insect) Proportion & concent. of the microemulsion Standardized EC M: EC Deltamethrin 0, 76 0. 145 0.52 (25 g / 1) Cypermethrin 0, 10 0 0.200 0, 5 (100 g / 1) Fervalerato 0.342 0.617 0.55

Regarding the three pyrethroids tested, it can be seen that there is the same order of reduction in the LD ^ q value, that is, about 50%.

EXAMPLE C

A cypermethrin formulation, as prepared in Example 3, was used to treat a crop of apples discovered in southern Nottinghamshire, which were infested with tortrix larvae. The formulation of Example 3 was diluted at rates of 2.5.3.3 ', 5.0 and 10.0 ml / 20 l and was compared with a control formulation (cypermethrin AMBUSH C). The AMBUSH C formulation was diluted at rates of 2.5.5.0 and 10 ml / 20 1. (10.0 ml of AMBUSH C per 20 liters is the normal dilution rate for this product). These treatments, together with the untreated control, are shown in Table 5. The AMBUSH mine is a brand.

TABLE 5

Treatment No. Product Rate ml / 20 1

1 Not treated - 2 Example 3 2.5 3 Example 3 3.3 4 Example 3 5.0 5 Example 3 10, 0 6 AMBUSH C 2.5 7 AMBUSH C 5.0 8 AMBUSH C 10, 0

-39The results were calculated by making a note of the number of live larvae three days after treatment; weak or dead larvae were removed by a heavy downpour before calculation. The trial comprised four repetitions. The number of larvae that remained, as well as the degree of control (percentage) of larvae compared to untreated plants, are shown in Table 6.

TABLE 6

No treatment

Rate (ml / 20 1) 0 2.5 3.3 5.0 10.0 2.5 5.0 10.0

Rep 1 Rep 2 Rep 3 Rep 4

0 0

0 0

0 0

0 0

1

0

0

0

0

1

0

0

Total

0 0

10% control

100. 0 100.0 100 .0 9 3.4 80 .0 9 3.4 100.0

Not treated

In Table 6, it can be seen that the formulation according to the invention is more effective, even at lower active ingredient concentrations, than a conventional formulation.

EXAMPLE D

The formulation in Example 3 was tested against various insect pests and small mites (namely Oryzaephilus surinamensis, Sitophilus granarius, Tribolium castaneum (insects) and Acarus siro and destructive Glycyphagus (small mites) and was compared with a standard preparation of pirimiphos -methyl, supplied in the form of an emulsifiable concentrate at 25% w / v. At the active ingredient rates of 1 ppm and 2 ppm, the reaction of the formulation of Example 3 was similar to the reaction of the standard preparation, but at the ingredient rates active of 0.5 ppm and 0.25 ppm, the formulation of the Example exceeded the reaction of the standard preparation

EXAMPLE E

The formulation of Example 3 was tested against the lower perforating cereal weevil (Rhyzoperthe dominica) and was compared with a standard preparation of pyrimiphosmethyl, supplied in the form of an emulsifiable concentrate at 25% w / v. The formulation of Example 3 at an active ingredient rate of 0.15 ppm gave a comparable reaction to the standard preparation at an active ingredient rate of 0.25 ppm.

ac-41EXAMPLE F

The formulation of Example 3 was tested against the lower grain-perforating weevil (Rhyzopertha dominica) in a six-month study. The raw number was measured at the following intervals after the start of the study and at the following concentrations:

Raw number

(%) wool week 22.Month 48.Month 62.Month 0.125 mg / kg 97 92 92 68 0.25 mg / kg 10 0 99 10 0 98 0, 5 mg / kg 100 100 100 100 1.0 mg / kg 100 100 100 100 2.0 mg / kg 100 10 0 100 10 0

The results are illustrated graphically in Figure 1. It can be seen that the initial high level of activity is substantially maintained during the duration of the study

-42 COMPARATIVE EXAMPLE G

A commercially available macroemulsified formulation of cypermethrin was tested under conditions identical to Example F in relation to the lower weevil, or grain perforator (Rhyzopertha dominica) in a six month study. The raw number was measured at the following intervals after the start of the study and at the following concentrations:

Raw number

(%) there Week 22.Month 42.Month 62.Month 0.125 mg / kg 100 0 0 0 0.25 mg / kg 100 0 0 0 0.5 mg / kg 100 0 0 0 1.0 mg / kg 100 0 0 0 2.0 mg / kg 10 0 0 0 0 The results are illustrated graphically in Figure 2 . It can be seen that the level is high the initial of activity is not maintained during the duration of es

everything, in contrast to the formulations of the invention.

-43 COMPARATIVE EXAMPLE H

A commercially available macroemulsified formulation of pyrimiphos-methyl was tested under conditions identical to Example F, for the lower grain-perforating weevil (Rhyzopertha dominica) over a six-month study. The raw number was measured at the following intervals after the start of the study and at the following concentrations:

Raw number

(%) wool week 29.Month 4 9.Month 69. 0.125 mg / kg 8 2 2 0 0.25 mg / kg 69 1 1 4 0, 5 mg / kg 98 4 5 5 1.0 mg / kg 99 2 10 8 2.0 mg / kg 98 8 16 7

graphically in Figure 3 of the initial activity only for the duration of the study, wind.

The results are illustrated. It can be seen that the elevated level is maintained only up to a small country in contrast to the formulations of the.

Claims (7)

13. - Process for the preparation of a water-miscible formulation, which is a microemulsion, a micellar solution or a molecular solution and whose average particle size is, at most 200 nm, characterized by the inclusion of water, a pesticidal oil, a surfactant and a co-surfactant, in which either the pesticidal oil is a pesticide or the pesticidal oil comprises a pesticide dissolved in the oil, in which the nonionic surfactant having hydrophilic / lipophilic (HLB) less than 10 comprises co-surfactant a balance 23. The method of claim 1, wherein the co-surfactant comprises a chain copolymer of ethylene oxide and propylene oxide or an alcohol ethoxylate. 33. The method of claim 2, wherein the co-surfactant comprises a chain copolymer of ethylene oxide and propylene oxide. 43. The process of claim 1, 2 or 3, characterized in that it comprises an anionic surfactant. according to the surfactant 53. The method of claim 4, wherein the surfactant is a hydrocarbon sulfonic acid. 6 ^a . Process according to claim 5, characterized in that the hydrocarbon sulfonic acid is an alkyl or alkylaryl sulfonic acid. 7 ^a . Process according to claim 5, characterized in that the hydrocarbon sulfonic acid is C-C-benzene sulfonate alkyl. O ± o 8 ^a . Process according to any one of claims 1 to 7, characterized in that the pesticidal oil consists substantially only of a pesticide. 9 ^a . Process according to any one of claims 1 to 8, characterized in that the formulation comprises on a w / v basis: oil (20 to 50%), surfactant (1 to 20%), co-surfactant (1 to 20%) and water (20 to 70%) with the proviso that the total number of parts of the ingredients, in percentage, cannot exceed 100 .. 10 ^a . Process according to any one of claims 1 to 8, characterized in that the formulation comprises on a w / v basis: oil (1 to 20%), surfactant (1 to 10%), co-surfactant (1 to 10%) and water (40 to 95)%, with the proviso that the total number of parts of the ingredients, in percentage, cannot exceed 100. 11 ^a . Process according to any one of claims 1 to 10, characterized in that a microemulsion is prepared. -4612a. Method for the protection of stored cereals against pests, characterized in that it comprises the application, to cereals, of a pesticidal formulation, prepared according to any one of claims 1 to 11.