GB2116535A - The use of formulations as compatibility agents in agriculture - Google Patents

Abstract

A formulation for use as a compatibility agent in pesticide/liquid fertiliser formulations comprises: a) an N-acyl sarcosinate, or a salt thereof, having the formula: RCON(CH3)CH2COOX I wherein R is a straight- or branched chain alkyl or alkenyl residue having from 2 to 18 carbon atoms and X is hydrogen, an alkali metal, the ammonium radical, a primary, secondary or tertiary amine group or a hydroxyalkylamine group; and b) a solvent or mixture of solvents for component a). i

Description

SPECIFICATION Use of formulations as compatibility agents The invention concerns the use of formulations in agriculture and particularly to the use of formulations as compatibility agents to improve the uniformity and stability of mixtures of liquid fertiliser and pesticides, thereby making it possible to spray previously unsprayable mixtures.

In general, pesticide and liquid fertiliser treatments need to be effected in separate stages because most pesticides are incompatible with liquid fertilisers, i.e. either they do not mix or they form unstable mixtures. This incompatibility can result in the formation of agglomerates of pesticide in the spray tank and thereby produce poor spraying performance with resultant damage to crops and/or ineffectiveness of treatment.

Clearly, there would be considerable economic advantages in combining the pesticide and liquid fertiliser treatments, as a result of eliminating one or more field operations.

Previous attempts to combine pesticides and liquid fertilisers into a single uniform and stable mixture have involved the incorporation of known emulsifying or suspending agents. The use of such materials, as compatibility agents, has proved unsatisfactory.

Surprisingly, we have now found that the use of certain N-acyl sarcosinates, or their salts, as compatibility agents, facilitates the production of uniform and stable suspensions or emulsions of pesticides in liquid fertilisers.

Accordingly, the present invention provides a method of using, as a compatibility agent in pesticide/liquid fertiliser mixtures, a formation comprising: a) N-acyl sarcosinate or a salt thereof having the formula: RCON(CH3)CH2COOX wherein R is a straight or branch chain alkyl or alkenyl residue having from 2 to 1 8 preferably 8-17 carbon atoms and X is hydrogen, an alkali metal, the ammonium radical, a primary, secondary or tertiary amine group or a hydroxy aikylamine group; and b) A solvent or mixture of solvents for the component a).

Preferably, the compatibility agent formulations used in the present invention contain 20-99, more preferably 6080% by weight of solvent and 1-80 more preferably 2040% by weight of the compound of formula I.

In the compounds of formula I, alkyl substituents R include ethyl, propyl, butyl, pentyl, hexyl, heptyl, nonyl, undecanyl, tridecanyl, pentadecanyl and heptadecanyl groups and alkenyl substituents R include prop-2-enyl, but3-enyl, pent-4-enyl, hex-5-enyl, hept-6-enyl and heptadec-8-enyl groups.

Examples of compounds of formula I include ethanoyl-, propanoyl, butanoyl, hexanoyl-, octanoyl, decanoyl-, lauroyl, tetradecanoyl-, hexanoyl, and octadecanoyl sarcosines, and in particular their salts e.g. their alkali metal especially their sodium salts; their ammonium salts; their alkyl (1 4) amine salts; and their triethanolamine salts.

Of particular interest are salts of compounds of formula I in which R is 8-1 7C alkyl, most especially N-lauroyl sarcosinate sodium salt having the formula: CH3(CH2)10CON(CH3)CH2 COONa The solvent, component (b), may be e.g. an aqueous system (which may or may not contain one or more co-solvents) or a non-aqueous system e.g. a polar alcohol. Examples of solvent components are water (which is the preferred solvent); methanol, methanol/water mixtures (in all proportions); ethanol/water mixtures containing up to 50% by weight of ethanol; propan-2-ol/water mixtures containing up to 50% by weight of propan-2-ol; and methanol/ethanol mixtures containing up to 50% by weight of ethanol.

The most preferred compatibility agent used in the invention is an aqueous solution of sodium lauroyl sarcosinate containing approximately 30% by weight of N-lauroyl sarcosinate sodium salt.

This preferred material which is commercially available (CIBA-GEIGY) under the trade name "SARKOSYL NL" is a colourless solution having a specific gravity of approximately 1.035 and a viscosity of 20 cps.

The present invention also provides a stable and uniform combined liquid fertiliser/pesticide mixture comprising: (i) liquid fertiliser; (ii) pesticide; (iii) a sarcosinate of formula I as hereinbefore defined; and (iv) a solvent or mixture of solvents for component (iii); As well as methods of producing such mixtures.

The concentrations of the liquid fertiliser and the pesticide components of the combined mixtures of the invention will vary according to the nature of the particular active ingredient and its use rate.

The concentration of the sarcosinate compound of formula I is preferably within the range of from 0.01 to 5%, more preferably from 0.01% to 1% by volume, based on the total volume of the mixture.

The preferred method of producing the combined fertiliser/pesticide mixtures of the invention comprises: a) adding to the liquid fertiliser, e.g. in the spray tank, from 0.01 to 5%, preferably from 0.01 to 1% by volume (based on the total volume of the mixture) of a solution of the sarcosinate compound of formula I and optionally mixing thoroughly; b) adding the pesticide to the mixture so produced; and then c) thoroughly agitating the whole mixture.

As an alternative procedure, a premix of the required amounts of pesticide and a solution of the compound of formula I may be prepared in water; this premix added to the required amount of liquid fertiliser present e.g. in the spray tank and the whole is then mixed thoroughly. This premix variation is recommended for those instances in which fertilisers of high phosphate content and high viscosity are used.

The liquid fertilisers used in the mixture of the present invention may be e.g. liquid nitrogen fertilisers (optionally containing phosphate and/or potash components) and foliar feeds or other formulations containing micro-nutrients e.g. trace elements. Such mixed liquid fertilisers are usually designated by their percentage weight N-P-K ratios e.g. 4-10-10, 6-18-18 or 10-30-0.

Fertilisers not containing nitrogen (e.g. 0-6-6) may also be used.

Pesticides which present particular problems in terms of their incompatibility with liquid fertiliers include PREBANE 500L (50% w/v terbutryne suspension concentrate), HYTANE 500L (50% w/v isoproturon suspension concentrate), GESAPRIM 500L (50% atrazine suspension concentrate), DICURANE 500L (50% w/v chlortoluron suspension concentrate), FUBOL 58 WP (10% w/w metalaxyl+ 48% w/w mancozeb wettable powder), OPOGARD 500L (35% w/v terbutyrne+ 15 w/v terbuthylazine suspension concentrate) and SAPECORN 24 EC (24% w/w chlorfenvinphos emulsifiable concentrate).

As already mentioned, variations in such parameters as density, viscosity, salt concentration and nutrient analysis of liquid fertilisers, and the different effects on such parameters when various pesticides are added, can affect the compatibility balance between the fertiliser and the pesticide. Moreover, a liquid fertiliser with a nominally identical composition may be formulated sufficiently differently by various manufacturers that the fertiliser may respond variably in terms to its compatibility with the pesticide component.

For these reasons, and in order to determine the optimum amount of compatibility agent required for particular liquid fertiliser/pesticide combinations, it is desirable to carry out a compatibility test on each individual fertiliser/pesticide combination.

A suitable laboratory compatibility test procedure is as follows: Compatability test procedure 1. To 2x 100 ml measuring cylinders add the appropriate dose of fertiliser. Mark one cylinder with a "+" sign.

2. Add 0.05 ml of compatibility agent to the marked cylinder, stopper the cylinder and invert 10 times.

3. Add the required amount of pesticide to both cylinders. If the pesticide is a wettable powder formulation, a pre-slurry will need to be made using liquid fertiliser from the appropriate cylinder.

4. Stopper the cylinders and invert 10 times.

5. Leave the cylinders to stand and inspect the uniformity of the suspensions at 5 minute intervals up to 30 minutes.

Evaluation of results If the mixture in the marked cylinder does not show a significant improvement in the stability and uniformity when compared to the mixture in the unmarked cylinder, the test is repeated using 0.1 ml or more of the compatibility agent. If a level of 0.5 ml is reached and the mixture is still not sufficiently stable and uniform, a premix of pesticide with compatibility agent with an equal amount of water is prepared and added to the liquid fertiliser with mixing to yield the optimum result.

When evaluating compatibility to determine the appropriate use rate of the compatibility agent, a minimum stability period of 30 minutes without agitation is considered the acceptable criterion. Any mixture which requires the use of a compatibility agent should be sprayed as soon after mixing as possible with minimum time taken for transportation between fields.

The suspensions and emulsions of liquid fertiliser and pesticide combinations produced according to the invention are more uniform in composition and more stable than those produced without the addition of sarcosinate compounds of formula I.

The invention is further illustrated by the following Examples.

Example 1 The Compatibility Test Procedure was used to evaluate the compatibility of the herbicide PREBANE 500L (50% w/vTerbutryne suspension concentrate; use rate 5.6 litres per ha.) with Fertiliquid F12, 3-10-10 liquid fertiliser (use rate 354 litres per ha.), Chafer 4-12-12 (use rate 400 litres per ha.), Omnia 4-10-10 (use rate 330 litres per ha.) and Billericay Farm Services 3.3-10-10 (user rate 280 litres per ha.) Clear Liquid Fertilisers. The compatibility agents used were based on (a) Oleoyl sarcosinate, acid form; (b) Oleoyl sarcosinate, sodium salt, (c) Oleoyl sarcosinate, ammonium salt and (d) Oleoyl sarcosinate, triethanolamine salt. Each sarcosinate was dissolved in water at a concentration of 30% w/w and the resultant compatibility agents were used at a rate of 0.05%, equivalent to 50 ml per 100 litres of liquid fertiliser. Controls containing no compatibility agent were also prepared.

In the control cylinders, the pesticide particles began to flocculate immediately and separation was complete within 5 minutes. In the cylinder containing the oleoyl sarcosinate acid form, flocculation began after 5 minutes and separation was complete after 1 5 minutes. In the cylinders containing the other compatibility agents, stability and uniformity remained for over 6 hours.

Example 2 The compatibility test procedure was used to evaluate the compatibility of the herbicide HYTANE 500L (isoproturon 50% suspension concentrate; use rate 5 litres per hectare) with Fertiliqiud F22, 3-10-6 liquid fertiliser (use rate 500 litres per hectare). The compatibility agents used were based on: a) lauroyl sarcosinate sodium salt b) coconut oil sarcosinate sodium salt c) palm kernel oil sarcosinate sodium salt and d) oleoyl sarcosinate sodium salt.

The sarcosinates were separately dissolved in water at a concentration of 30% w/w and the resultant compatibility agents were used at a rate of 0.05%, equivalent to 50 ml to 100 litres of liquid fertiliser. A control cylinder with no compatibility agent was also prepared.

In the control, dispersion was not complete and flocculation of the dispersed herbicide particles were observed immediately. Separation was complete within 5 minutes.

In the cylinder containing the oleoyl sarcosinate sodium salt flocculation began after 5 minutes and separation was complete after 10 minutes.

In the cylinder containing the palm kernel oil sarcosinate sodium salt flocculation began after 5 minutes and separation was complete after 1 5 minutes.

In the cylinder containing the coconut oil sarcosinate sodium salt, flocculation began after 5 minutes and separation was complete after 20 minutes.

In the cylinder containing the lauroyl sarcosinate sodium salt, flocculation began after 1 5 minutes and separation was complete after 40 minutes.

Example 3 The Compatibility Test Procedure, described hereinbefore, was used to evaluate the compatibility of the fungicide FUBOL 58 WP (metalaxyl 10%+mancozeb 48% wettable powder, use rate 3 kg per ha), with the following foliarfeeds; Complessal (use rate 4.2 kg per ha.), Stimufol (user rate 2 kg per ha.) and Polyverdol (use rate 8 kg per ha.), all of which are formulations containing micronutrients.

The compatability agent used was a formulation containing 32.5% of a coconut oil sarcosinate (sodium salt) and 67.5% water. The foliar feeds were first dispersed in water at a rate equivalent to 200 litres of solution per ha. and the compatibility agent was added at a rate equivalent to 300 ml per 100 litres of solution (0.3%).

FUBOL 58WP was then added to the foliar feed solutions. Controls containing no compatibility agent were also prepared.

In the controls, complete separation of the fungicide from the foliar feed solution occurred in less than 5 minutes. In the measuring cylinders containing compatibility agent, excellent suspensions were formed. After 30 minutes further observations were made and the suspensions in the measuring cylinders containing the compatibility agent remained uniform with no evidence of separation.

Example 4 The Compatibility Test Procedure was used to evaluate the compatibility of the herbicide DICURANE 500L (chlortoluron 50% w/v suspension concentrate, use rate 7 litres per ha.) with Omnia 2-6-12,4-10-10 and 6-13-8 clear liquid fertilisers use rate 300 litres per ha).

The premix method was used with compatibiity agent at the rate of 0.3% (300 ml per 1 00 litres of fertiliser). The compatibility agent used was a palm kernel oil sarcosinate sodium salt 30% w/v in water. Control cylinders with no compatibility agent were also prepared.

In the controls, separation was complete within 5 minutes. The cylinders containing compatibility agent remained stable after 30 minutes.

Exampe 5 The compatibility test procedure was used to evaluate the compatibility of the insecticide SAPECRON 24EC (chlorfenvinphos 25% w/v emulsifiable concentrate, use rate 5.6 litres per ha.) with B.F.S. 3.3-10-10 clear liquid fertiliser (use rate 280 litres per ha).

The Compatibility agent used was 30% by weight lauryl sarcosinate sodium salt and 70% methanol.

The premix method was used with compatability agent at a rate of 0.3% by volume (300 ml per 100 litres of fertiliser). A control cylinder containing no compatibility agent was also prepared.

In the control cylinder, separation was complete within 5 minutes, whereas in the cylinder containing the compatibility agent, the mixture remained uniform for 30 minutes.

Example 6 The compatibility test procedure was used to evaluate a mixture of a 50% w/v atrazine suspension concentrate (use rate 3.4 litres per hectare) and 6-13-8 liquid fertiliser (use rate 200 litres per hectare).

The 50% atrazine suspension concentrate was premixed with an equal volume of water, to ensure complete dispersion in the fertiliser, and to this was added a 30% w/v aqueous solution of N-lauroyl sarcosinate sodium salt at a rate equivalent to 300 ml of compatibility agent per 1 00 litres of fertiliser. This mixture was then added to the fertiliser.

A control containing no compatibility agent was prepared using the same method.

In the control cylinder, flocculation was apparent after 5 minutes and separation was complete after 30 minutes.

In the cylinder containing the compatibility agent flocculation was not apparent until after 25 minutes and separation was not complete until well over 120 minutes had elapsed.

Claims (22)

Claims

1. The use, as a compatibility agent in pesticide/liquid fertiliser mixtures of a formulation comprising: a) an N-acyl sarcosinate, or a salt thereof, having the formula: RCON(CH3)CH2COOX wherein R is a straight- or branched chain alkyl or alkenyl residue having from 2 to 1 8 carbon atoms and X is hydrogen, an alkali metal, the ammonium radical, a primary, secondary or tertiary amine group or a hydroxyalkylamine group; and b) a solvent, or a mixture of solvents for component a).

2. Use according to claim 1 wherein the compound of formula I is used in the form of a salt.

3. Use according to claim 1 or 2 of a formulation containing 20-99 weight% of solvent and 1-80 weight% of the compound of formula I.

4. Use according to claim 3 of a formulation containing 60-80 weight% of solvent and 2040 weight% of the compound of formula

5. Use according to any of the preceding claims wherein the compound of formula lisa C8-C17 alkyl sarcosinate or its sodium-, ammonium- or triethanol-amine salts.

6. Use according to claim 5 wherein the compound of formula I is N-lauroyl sarcosinate sodium salt.

7. Use according to claim 6 wherein the formulation is an aqueous solution containing approximately 30% by weight of N-lauroyl sarcosinate sodium salt.

8. Use according to claim 1 substantially as described with reference to any of the Examples.

9. A combined liqoid fertiliser/pesticide mixture comprising (i) a liquid fertiliser; (ii) a pesticide; (iii) a compound of formula I as defined in claim 1; and (iv) a solvent or mixture of solvents for component (iii).

10. A mixture according to claim 9 wherein the concentration of the compound of formula I is within the range of from 0.01 to 5% by volume, based on the total volume of the mixture.

11. A mixture according to claim 10 wherein the concentration of the compound of formula I is within the range of from 0.01 to 1% by volume, based on the total volume of the mixture.

12. A mixture according to any of claims 9 to 11, wherein the liquid fertiliser is a liquid nitrogen fertiliser (optionally containing phosphate and/or potash components) or a foliar feed.

13. A mixture according to any of claims 9 to 12 wherein the pesticide is a terbutryne suspension concentrate, an isoproturon suspension concentrate, an atrazine suspension concentrate, a chlortoluron suspension concentrate, a metalaxyl/mancozeb wettable powder, a terbutryne/terbuthylazine suspension concentrate or a chlorfenvinphos emulsifiable concentrate.

14. A mixture according to any of claims 9 to 1 3 wherein the solvent is water.

1 5. A mixture according to claim 9 substantially as described with reference to any of the Examples.

1 6 A method of producing a mixture as defined in claim 9 comprising the steps of: a) adding to the liquid fertiliserfrom 0.01 to 5% by volume, based on the total volume of the mixture, of a solution of the compound of formula I as defined in claim 1, and optionally mixing thoroughly the mixture so obtained, b) adding the pesticide component to the mixture produced in step a); and c) thoroughly agitating the whole mixture.

17, A method according to claim 16 wherein steps a) to c) are effected in a spray tank.

18. A method of producing mixture as defined in claim 9 comprising the steps of: a) preparing a premix of the required amounts of pesticide and a solution of the compound of formula in water b) adding the premix from step a) to the required amount of liquid fertiliser; and c) agitating the whole mixture thoroughly.

1 9. A method according to claim 1 8 wherein steps b) and c) are effected in a spray tank.

20. A method according to claim 18 or 19 wherein the fertiliser used is of high phosphate content and of high viscosity.

21. A method according to claim 1 6 or 18 substantially as described with reference to any of the Examples.

22. A combined liquid fertiliser/pesticide mixture when produced by a method claimed in anyofclaims 18to21.