Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
  • B01J13/02—Making microcapsules or microballoons
  • B01J13/06—Making microcapsules or microballoons by phase separation
  • B01J13/14—Polymerisation; cross-linking
  • B01J13/16—Interfacial polymerisation
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
  • A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
  • A01N25/26—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests in coated particulate form
  • A01N25/28—Microcapsules or nanocapsules

Definitions

• This invention includes a method for delaying or preventing crystallization of materials susceptible to such crystallization by the use of a microencapsulation process.
• this invention includes a method for delaying or preventing crystallization through the use of encapsulated droplets of a solution of an active material which is substantially insoluble in aqueous conditions, where the encapsulating agent is a film formed from a modified urea-formaldehyde polymer.
• membranes, coatings, and capsules for the controlled release of liquid materials is well known in the art of both agricultural and non-agricultural chemicals.
• controlled-release techniques have improved the efficiency of herbicides, insecticides, fungicides, bactericides, and fertilizers.
• Non-agricultural uses include encapsulated dyes, inks, pharmaceuticals, flavoring agents, and fragrances.
• controlled-release materials are coated droplets or microcapsules, coated solids including both porous and non-porous particles, and coated aggregates of solid particles.
• a water-soluble encapsulating film is desired, which releases the encapsulated material when the capsule is placed in contact with water.
• Other coatings are designed to release the entrapped material when the coating is ruptured by external force.
• coalings are porous in nature and release the enlrapped material Io the surrounding medium at a slow rate by diffusion through the pores.
• coatings also serve to facilitate the dispersion of water-immiscible liquids into water and water-containing media such as wet soil. Droplets encapsulated in this manner are particularly useful in agriculture, where water from irrigation, rain, and water sprays is frequently present. A variety of processes for producing such capsules is known.
• microcapsules of uniform and readily controlled size which are suitable for use without further treatment, is disclosed in U.S. Patent No. 4,956,129 and U.S. Patent No. 5,332,584.
• the microcapsules described in these patents are substantially water-insoluble liquid materials within a porous shell.
• the patents disclose the material's slow release rate of the encapsulated materials through the shell through diffusion.
• Microcapsules formed by this process provide stability against crystallization and are capable of effecting a slow rate of release of the encapsulated liquid active solution by diffusion through the shell to the surrounding medium.
• the present invention resides in the ability to prevent or delay crystallization of these materials by use microcapsules formed by the process described above.
• the present invention can be readily adapted to accommodate variations in the active materials used, the kind of product desired, and economic factors in general. As the following indicates, both essential and optional features of the process and the product thereof can be varied over a wide range.
• the active material serving as the basis of the solution (i.e., the base solid) which forms the interior of the capsules (i.e., the core liquid) be of sufficiently small particle size.
• the particle size should be between 1 ⁇ m and 100 ⁇ m, preferably between 2 ⁇ m and 20 ⁇ m.
• the core liquid may consist of a solution of a single active base solid or one or more active solid base materials dissolved in an inert solvent.
• the core liquid solution may be saturated or supersaturated, but the solid base material is one that has a low melting point or low water solubility, i.e., the solid has a tendency to crystallize in the aqueous phase.
• a wide variety of active liquids can be encapsulated by the present process.
• the most useful liquids are those which do not react with either the prepolymer, the acid used in the self-condensation wall-forming step, or any of the other components in the system.
• any nonreactive liquid which will diffuse through the shell membrane is suitable.
• the liquid can be a single chemical compound or a mixture of two or more compounds. It can diffuse into water, soil, air, or any other surrounding medium.
• the liquids suitable for encapsulation by the process of the present invention should be solid at 30° C, have low solubility in water and at least moderate solubility in water-immiscible organic solvents.
• Liquids suitable for encapsulation include chemical-biological agents such as herbicides, insecticides, fungicides, nematocides, bactericides, rodenticides, molluscides, acaricides, larvicides, animal, insect, and bird repellents, plant growth regulators, fertilizers, pheromones, sex lures and attractants, pharmaceuticals and flavor and odor compositions.
• the microcapsules of the present invention are particularly well adapted to pesticides, including thiocarbamates, dithiocarbamates, acetamides. anilides, sulfonamides, bisamides, triazines, organophosphorus compounds, natural fermentation products, and pyrethroids.
• azamethiphos coumaphos, menazon, pyridaphenlhion, azinphos-ethyl, azinphos-methyl. dialifos, phosmet, pyrazophos, chlo ⁇ yrifos, chlo ⁇ yrifos-methyl, tebupirimfos, quinalphos, methidathion, bromophos, famphur, fenchlorphos, jodfenphos, parathion-methyl, temephos, trichlorfon, mecarphon, cyanofenphos, EPN leptophos, fenamiphos, phosfolan, acephate, isocarbophos, methamidophos, indoxacarb, metoxadiazone, dialifos, phosmet, tetramethrin, ⁇ pronil, tebufenpyrad, tolfen
• bifenlhrin cyfluthrin, gamma-cyhalothrin, lambda-cyhalothrin, cypermethrin, alpha-cypermethrin, beta-cypermethrin, theta- cypermethrin, zeta-cypermethrin, deltamethrin, fenfluthrin, fenpropathrin, fenvalerate, esfenvalerate, permethrin, resmethrin, bioresmethrin, tefluthrin, tetramethrin, tralomethrin, transfluthrin, etofenprox, flufenprox, halfenprox, pyrimidifen, chlorfenapyr, spiromesifen, diafenthiuron, sulcofiiron sodium, hydramethylnon, isoprothiolane, mal
• Cymoxanil dodine, guazatine, iminoctadine, carpropamid, chloraniformethan, cyilufenamid, diclocymet, ethaboxam, fenoxanil, furametpyr, mandipropamid, penthiopyrad, prochloraz, silthiofam, triforine, benalaxyl, benalaxyl-M, furalaxyl, metalaxyl, metal&xyl-M, boscalid, carboxin, fenhexamid, metsulfov&x, ofurace, oxadixyl, oxycarboxin, thifluzamide, tiadinil, benodanil, flutolanil, mebenil, fenfuram, methfuroxam, flusulfamide, trichlamide, zarilamid, zoxamide, furmecyclox,
• chlozolinate iprodione, myclozolin, procymidone, vinclozolin, captafol, captan, ditalimfos, folpet, binapacryl, dinobuton, DNOC, cyazofamid, fenamidone, glyodin, peflurazoate, dimethomo ⁇ h, dodemorph, flumorph, pyrazophos, fentin acetate, chlozolinate, drazoxolon, famoxadone, hymexazol, myclozolin, vinclozolin, furametpyr, penthiopyrad, buthiobate, fluazinam, cyprodinil, diflumetorim, ethirimol, fenarimol, ferimzone, mepanipyrim, nuarimol, pyrimethanil, ienpiclonil, lludioxonil, llu
• halacrinate halacrinate, quinoxyfen, dithianon, chinomethionat, ethoboxam, methasulfocarb, anilazine, bilertanol, fluotrimazole, pencycuron, acibenzolar-methyl.
• pesticides are preferred, and certain classes of pesticides are particularly preferred.
• One such class is that of azole fungicides.
• This class of compounds includes those disclosed in U.S. Patent No. 4,243,405, which is incorporated by reference in its entirety as if specifically set forth herein.
• Specific compounds within this class include azaconazole, bitertanol, bromuconazole, cyproconazole, difenoconazole, diniconazole, fenbuconazole, fluquinconazole, flusilazole, flutriafol, hexaconazole, ipconazole, metconazole, myclobutanil, penconazole, prochloraz, propiconazole, tebuconazole, tetraconazole, triadimefon, triadimenol, triflumizole, triticonazole, and uniconazole.
• Also included in the types of core liquids useful in the present invention include solutions of azoxystrobin, trifloxystrobin, fiuoxystrobin, metalaxyl-M, benalazyl, furalaxyl, tefluthrin, thiamethoxam, imidacloprid, clothianidin, thiacloprid, abamectin, lambda-cyhalothrin, aldicarb, fipronil, among others.
• azoxystrobin trifloxystrobin, fiuoxystrobin, metalaxyl-M, benalazyl, furalaxyl, tefluthrin, thiamethoxam, imidacloprid, clothianidin, thiacloprid, abamectin, lambda-cyhalothrin, aldicarb, fipronil, among others.
• the antidote helps to protect the crop from injury by the herbicide, without appreciable effect on the potency of the herbicide against the undesired weed species.
• the antidote thus renders the herbicide more selective in its action.
• Useful antidotes include acetamides such as N,N-diallyl-2,2-dichloroacetamide and N,N-diallyl-2- chloroacetamide, oxazolidines such as 2,2,5-trimethyl-N-dichloroacetyl oxazolidine and 2,2 spirocyclohexyl-N-dichloroacetyl oxazolidine, and 1,8-naphthalic anhydride.
• the antidote is present in the composition in a non-phytotoxic, antidotally effective amount.
• non-phytotoxic is meant an amount which causes at most minor injury to the crop.
• antidotally effective is meant an amount which substantially decreases the extent of injury caused by the pesticide to the crop.
• the preferred weight ratio of pesticide to antidote is about 0.1 : 1 to about 30: 1. The most preferred range for this ratio is about 3; 1 to about 20:1.
• synergists are compounds which have little or no pesticidal activity of their own, but when combined with a pesticide produce a combination with a potency significantly greater than the additive sum of the potencies of the compounds applied individually.
• synergists include 5- 1-[2-(2- ethoxyethoxy)ethoxy]ethoxy -1,3-benzodioxole (sesamex), l,4-di-(l,3-benzodioxol- 5-yl)tetrahydrofuro [3,4-c] furan (sesamin), l-methyl-2-(3,4- melhylenedioxyphenyOelhyl oclyl suphoxide (sulfoxide), and 5-[2-(2- butoxyethoxy)ethoxymethyll-6propyl- 1,3-benzodioxole (piperonyl butoxide).
• synergists are present in effective amounts, i.e., at any pesticide to-synergist ratio at which a synergistic effect is observed. This ratio varies widely from one combination to the next.
• Prepolymers suitable to the present invention are partially etherified urea- formaldehyde prepolymers with a high solubility in the organic phase and a low solubility in water.
• the prepolymer In its non-etherified form, the prepolymer contains a large number of methylol groups, -CH 2 OH, in its molecular structure.
• Etherification is the replacement of the hydroxyl hydrogens with alkyl groups, and is achieved by condensation of the prepolymer with an alcohol.
• the alkyl groups comprise four carbon atoms or more and they have replaced more than about 50% of the hydroxyl hydrogen atoms on the prepolymer molecule, the prepolymer becomes soluble in the organic phase.
• the prepolymers useful in the present invention are those in which from about 50% to about 98% of the hydroxyl hydrogen atoms have been replaced by alkyl groups of 4 to 10 carbon atoms each. In preferred practice, about 70% to about 90% of the groups have been etherified with a C 4 C6 alcohol. Both straight-chain and branch ed-chain alcohols are useful in the present invention, and all carbon atom ranges quoted herein are to be inclusive of their upper and lower limits.
• Etherified urea-formaldehyde prepolymers are commercially available as solutions in alcohol or in a mixture of alcohol and xylene.
• the alcohol used as the solvent is normally identical to that used as the etherifying agent.
• Those in most common use are n-butanol and iso-butanol.
• the degree of etherification (butylation) in these commercial products ranges between 70% and 90%, and the solution contains from 50% to 85% by weight of prepolymer. Minor amounts of free formaldehyde are also frequently present.
• These solutions are typically sold as cross-linking agents for alkyd resins and used primarily for the formulation of coating and finishing products such as pain Is and lacquers.
• Urea-formaldehyde prepolymers which have not been etherified are also available commercially, either in aqueous solutions or as water dissolvable solids, for use as adhesives. These can be etherified by condensation with the desired alcohol in a weakly acidic alcohol solution. The water of condensation is distilled off as an azeotrope with the alcohol until the desired degree of condensation (etherification) has been reached.
• Urea-formaldehyde prepolymers themselves can be prepared by known techniques, notably the base-catalyzed reaction between urea and formaldehyde in water at a weight ratio of 0.6 to 1.3 parts formaldehyde to one part urea by weight (1.2:1 to 2.6:1 on a molar basis), at a pH of 7.5 to 11.0 and a temperature of 5O 0 C to 90° C. Etherification is then accomplished as described in the preceding paragraph.
• the degree of etherification can be monitored by the quantity of water driven off during the distillation. Although the degree of etherification can be varied over a wide range to accommodate the needs of the reaction system, the rate of polymerization in the subsequent wall-forming step decreases as the degree of etherification increases. Too high a degree of etherification. therefore, tends to inhibit the progress of the wall formation. However, the water solubility of the prepolymer also decreases with increasing degree of etherification. Since low water solubility is a desirable feature of the prepolymer, it is best to avoid too low a degree of etherification. Thus, the suitable and preferred ranges are those stated above.
• the organic solution comprising the core liquid and the etherilled prepolymer is most conveniently formed when the latter is predissolved in a solvent, as it is when commercially sold for the coatings and finishings industry. In the absence of such a solvent, there is a high degree of hydrogen bonding between the hydroxyl groups, and the prepolymer is a waxy solid which is difficult to dissolve in the capsule core liquid.
• Polar organic solvents are particularly useful for preventing the hydrogen bonding and dissolving the prepolymer; examples include alcohols, ketones, esters, and aromatics. When etherifying agents of high chain length are used, aliphatics and other non-polar solvents can also be used. The most useful solvents are lhe same alcohols used as lhe etherifying agents, the solution being taken directly from the reaction mixture of the etherification process.
• the concentration of the prepolymer in the organic phase is not critical to the practice of the invention, but can vary over a wide range depending on the desired capsule wall strength and the desired quantity of core liquid in the finished capsule. It will be most convenient, however, to use an organic phase with a prepolymer concentration of from about 1% to about 70% on a weight basis, preferably from about 5% to about 50%.
• Optional additives include solvents, polymerization catalysts, and wall-modifying agents.
• Solvents provide a means for controlling the wall-forming reaction. As explained in Section E below, the reaction occurs when protons come in contact with the urea- formaldehyde prepolymer.
• the organic phase must be sufficiently hydrophilic to attract protons to the interface from the bulk of the aqueous phase, yet sufficiently hydrophobic to prevent large amounts of protons from crossing the interface and causing polymerization to occur throughout the bulk of the droplet.
• An appropriately selected solvent added to the organic phase can correct the character of the organic phase to achieve these results.
• the need for a solvent and the type of solvent needed-hydrophobic or hydrophilic- dependss on the nature of the liquid core material.
• Aliphatic and alicyclic solvents are examples of hydrophobic solvents
• alcohols and ketones are examples of hydrophilic solvents. The amount of solvent can be varied as needed to achieve the desired results.
• Catalysts capable of enhancing the wall-forming reaction can be placed in either the aqueous or organic phase.
• Catalysts are generally used when the core material is too hydrophobic, since they serve to attract protons toward the organic phase.
• Any water- soluble catalyst which has a high affinity for the organic phase and is capable of carrying a prolon can be used.
• Carboxylic and sulfonic acids are particularly useful. Examples include orthochlorobenzoic acid, 2-phenyl-2,2-dichloroacetic acid, benzoic acid, salicylic acid, p-toluenesulfonic acid and dodecylbenzene sulfonic acid.
• the same catalytic effect can be accomplished by dissolving salts of these acids in the aqueous or organic phase and then acidifying the aqueous phase. The acid form is produced by ion exchange.
• Wall-modifying agents serve to modify the character of the wall by varying its permeability to the core material.
• Suitable wall-modifying agents contain a substantial number of hydroxy 1 or mercapto groups capable of reacting with the methylol groups on the prepolymer.
• the wall modifier can be used in the organic solution to add multiple linkages to the methylol groups to increase the degree of cross-linking, or to exhaust active sites on the prepolymer to decrease the degree of cross-linking.
• the permeability of the wall (and consequently the release rate of the core liquid) can be either increased or decreased.
• Castor oil is one example of such an agent.
• the preferred cross-linking wall-modifying agent is pentaerythritol tetrakis (mercaptopropionate) sold under the tradename MERC APT ATE Q-43 ESTER, by Cincinnati Milacron Chemicals.
• MERC APT ATE Q-43 ESTER mercaptopropionate
• Other poly-functional mercaptan esters of a similar nature can be used.
• an emulsion is formed by dispersing the organic solution in an aqueous solution comprising water and a surface-active agent.
• the relative quantities of organic and aqueous phase are not critical to the practice of the invention, and can vary over a wide range, limited mostly by convenience and ease of handling. In practical usage, the organic phase will comprise a maximum of about 55% by volume of the total emulsion and will comprise discrete droplets of organic solution dispersed in the aqueous solution.
• the surface-active agent can be any of the wide variety of compounds known to be useful for lowering the surface tension of a fluid interface.
• Nonionic and anionic types are bolh useful.
• Examples of nonionic agents are long chain alkyl and mercaptan polyethoxy alcohols, alkylaryl polyethoxy alcohols, alkylaryl polyether alcohols, alkyl polyether alcohols, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene ethers, and polyethylene glycol esters with fatty or rosin acids.
• anionic agents are the calcium, amine, alkanolamine, and alkali salts of alkyl and alkylaryl sulfonates; vegetable sulfonates; and ethoxylated and propoxylated mono- and dielhers of phosphoric acid.
• Blends of surface-active agents are also useful.
• Preferred surface-active agents are polyethelene glycol ethers of linear alcohols and alkali salts of alkyl and alkylaryl sulfonates.
• the quantity of surface-active agent is not critical to the invention, and can vary over a wide range.
• the agent generally comprises from about 0.1% to about 5.0% by weight of the aqueous phase.
• the agent can be added before or after the emulsion is formed.
• emulsion stability can be enhanced by adding a protective colloid to the aqueous phase.
• a protective colloid stabilizes a dispersed system against aggregation, flocculation, and coalescense.
• Many materials are known to function as protective colloids and are available commercially, including polyvinyl alcohols, alginates, alpha- and gamma protein, casein, methyl cellulose, carboxymethyl cellulose, gelatin, glues, natural gums, polyacids, and starch.
• the colloid can be added to the aqueous phase prior to the formation of the emulsion, or to the emulsion itself after it has been formed. Although the colloid is an optional additive, its inclusion in the present system is preferred. Polyvinyl alcohol protective colloids are particularly preferred.
• Additional compounds which serve as protective colloids are the salts of lignin sulfonate, such as the sodium, potassium, magnesium, calcium or ammonium salts.
• lignin sulfonates such as the sodium, potassium, magnesium, calcium or ammonium salts.
• commercial lignin sulfonates are TREAX®, LTS, LTK and LTM, respectively, the potassium, magnesium and sodium salts of lignosulfonate (50% aqueous solutions), Scott Paper Co., Forest Chemical Products; MARASPERSE CR® and Marasperse CBOS-3®, sodium lignosulfonate, American Can Co.: Polyfon 0®, Polyfon T®, Reax 88B®, Reax 85B®, sodium sails of lignin sulfonate and Reax C- 21®, calcium salt of lignin sulfonate, Westvaco Poly chemicals; Orzan S and Orzan A, the sodium and ammonium salts
• the actual quantity of colloid is not critical and any amount which is effective in enhancing the stability of the emulsion can be used. It is most convenient to use between about 0.1% and about 5.0% colloid by weight in terms of the aqueous phase.
• the droplet size in the emulsion is not critical to the invention. For greatest utility of the final product, the droplet size will fall in the range of about 0.5 microns to about 4000 microns in diameter. The preferred range for most pesticidal applications is from about 1 micron to about 100 microns in diameter.
• the emulsion is prepared by the use of any conventional high shear stirring device. Once the desired droplet size is attained, mild agitation is generally sufficient to prevent droplet growth throughout the balance of the process.
• the system is acidified to a pH of between about 0 and about 4.0, preferably between about 1.0 and about 3.0.
• This causes the etherified urea-formaldehyde prepolymer to polymerize by self- condensing in situ and from a shell completely enclosing each droplet.
• Acidification can be accomplished by any suitable means, including adding any acid which is water-soluble, including formic acid, citric acid, hydrochloric acid, sulfuric acid, phosphoric acid, and the like. Acidification can also be achieved by the use of acidic dispersants or surface-active agents, provided that such components are added to the system after the emulsion has been formed.
• the in situ self-condensation polymerization reaction is self-terminating and is generally allowed to run to completion.
• the reaction can be arrested before completion, however, by raising the pH.
• the wall tightness, rigidity, and permeability can be controlled. This can also be accomplished in most cases by a wall modifier as described above.
• the rate of the in situ self-condensation polymerization reaction increases with both acidity and temperature depending upon the pH.
• the reaction can therefore be conducted anywhere within the range of about 20° C to about 100 0 C, preferably between about 40 0 C and about 70° C.
• the reaction will generally be complete within a few hours, although with high acidity and high temperature, the reaction can be completed within minutes.
• the capsules can be stored and used as an aqueous dispersion, or filtered and recovered as dried capsules. In either form, the capsules are useful and effective in the slow release of the core liquid.
• Dispersions are preferably stabilized by dispersants dissolved in the continuous phase. Since most dispersants are more effective in neutral or basic solutions, it is preferable to raise the pH of the dispersion once the wall has been formed. This is accomplished by any water-soluble base. Any conventional dispersant can be used.
• Typical dispersants include lignin sulfonates, polymeric alkylnaphthalene sulfonates, sodium naphthalene sulfonate, polymethylene bis-naphthalene sulfonate, and sodiumN-methyl N-(long chain acid) taurates.
• a unique feature of the process of the invention is that the solid permeable polymer shells enclosing the organic phase droplets are formed by means of condensation of the urea-formaldehyde prepolymer in the organic phase adjacent to the interface formed between the organic phase droplets and the aqueous phase solution. This is a consequence of the urea-formaldehyde prepolymers being dissolved in the organic phase.
• the advantages of forming the polymer shells on the organic side of the interface are several.
• the first is that the process itself is more easily controlled than the prior art processes, which involve wall-forming condensation in the aqueous phase.
• the wall-forming polymer can deposit upon the walls of the container in which the emulsion is present, on the agitator or any other structure which may be present, in addition to depositing on the droplets.
• the wall-forming polymer that condenses on the organic side of the interface does not deposit on any of the container walls or other structures.
• the organic phase contains a pesticide
• a higher loading of organic phase results in a more concentrated pesticide formulation. This enables substantial cost savings to be achieved in manufacturing, packaging and transportation.
• An aqueous solution was prepared containing 309.6g water, 4.Og of an alkylnaphthalene sulfonate, sodium salt (CAS# 79103-93-8), and 11.2g of a naphthalene sulfonic acid polymer with formaldehyde, sodium salt (CAS# 50-00-0). The pH was then lowered to ⁇ 2.0 with concentrated sulfuric acid.
• a saturated organic solution was prepared by mixing 32Og of a mixture of the RS/SR and RR/SS diaseteomeric pairs of lhe fungicide propiconazole and 80g of 2- methylnaphthalene and raising the temperature to 50 0 C. This was then cooled to 3O 0 C and 52g of Cymel U-1050-10 Resin (a 60% n-butanol solution of a partially butylated urea-formaldehyde prepolymer in which the degree of butylation of 70-90%) was added.
• the organic solution was slowly added, with agitation, to the aqueous solution.
• the agilalion rale was lhe increased Io get an average particle size of lhe emulsion droplets to between 2 ⁇ m and 20 ⁇ m.
• the mixture was then heated to 55°C for three hours under gentle agitation. Heating was discontinued and the pH raised to 9 with ammonium hydroxide.
• An aqueous solution was prepared containing 309.6g water, 4.Og of an alkylnaphthalene sulfonate, sodium salt (CAS# 79103-93-8), and 11.2g of a naphthalene sulfonic acid polymer with formaldehyde, sodium salt (CAS# 50-00-0). The pH was then lowered to ⁇ 2.0 with concentrated sulfuric acid.
• a saturated organic solution was prepared by mixing 16Og of the fungicide myclobutanil and 24Og of 2-methylnaphthalene and raising the temperature to 5O 0 C.
• Cymel U-1050-10 Resin a 60% n-butanol solution of a partially butylaled urea-formaldehyde prepolymer in which the degree of butylation of 70-90%) was added.
• the organic solution was slowly added, with agitation, to the aqueous solution.
• the agitation rate was the increased to get an average particle size of the emulsion droplets to between 2 ⁇ m and 20 ⁇ m.
• the mixture was then heated to 55°C for three hours under gentle agitation. Heating was discontinued and the pH raised to 9 with ammonium hydroxide.

Landscapes

• Life Sciences & Earth Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• General Health & Medical Sciences (AREA)
• Health & Medical Sciences (AREA)
• Pest Control & Pesticides (AREA)
• Agronomy & Crop Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Dispersion Chemistry (AREA)
• Plant Pathology (AREA)
• Toxicology (AREA)
• Engineering & Computer Science (AREA)
• Dentistry (AREA)
• Wood Science & Technology (AREA)
• Zoology (AREA)
• Environmental Sciences (AREA)
• Manufacturing Of Micro-Capsules (AREA)
• Agricultural Chemicals And Associated Chemicals (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=39082896

Family Applications (1)

Country Status (4)

Cited By (6)

Citations (1)

• 2007
  • 2007-08-07 WO PCT/US2007/075310 patent/WO2008021800A2/en active Application Filing
  • 2007-08-14 CL CL2007002363A patent/CL2007002363A1/es unknown
  • 2007-08-14 AR ARP070103602 patent/AR062374A1/es unknown
  • 2007-08-14 TW TW96129947A patent/TW200831180A/zh unknown

Patent Citations (1)

Also Published As

Similar Documents

Legal Events