NZ330876A

NZ330876A - A coated stable pesticidal matrix comprising a ph dependant polymer and optionally a plasticiser a uv protector an activity enhancer and a glidant

Info

Publication number: NZ330876A
Application number: NZ33087698A
Authority: NZ
Inventors: Gaunglin Sun; Fakhruddin Ahmed; Bruce Christian Black
Original assignee: American Cyanamid Co
Priority date: 1997-07-09
Filing date: 1998-07-02
Publication date: 1999-10-28
Also published as: SG74058A1

Description

<div class="application article clearfix" id="description"> New Zealand Paient Spedficaiion for Paient Number 330876 New Zealand No International No 330876 PCT / TO BE ENTERED AFTER ACCEPTANCE AND PUBLICATION Priority dates 09 07 1997, Complete Specification Filed 02 07 1998 Classification (6) A01N25/26.14 Publication date 28 October 1999 Journal No 1445 NO DRAWINGS NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION Title of Invention Improved coated pestioidal matrices, a process for their preparation and compositions containing them Name, address and nationality of applicant(s) as in international application form AMERICAN CYANAMID COMPANY, a corporation of Five Giralda Farms, Madison, New Jersey 07940 0874, United States of America 3308 7 NEW ZEALAND PATENTS ACT, 1953 No Date COMPLETE SPECIFICATION IMPROVED COATED PESTICIDAL MATRICES, A PROCESS FOR THEIR PREPARATION AND COMPOSITIONS CONTAINING THEM We, AMERICAN CYANAMID COMPANY, a corporation organised and existing under the laws of the State of Maine, United States of Amenca, of Five Giralda Farms, Madison, New Jersey 07940 0874, United States of Amenca, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement - 1 - (followed by page la) ACY-33343 17 6.98 -1 a- IMPROVED COATED PESTICIDAL MATRICES. A PROCESS FOR THEIR PREPARATION AND COMPOSITIONS CONTAINING THEM Certain pesticidal agents are inactivated by ultraviolet radiation from the sun Because those pesticidal agents are useful for the control of pests and are applied m areas where they will be exposed to ultraviolet radiation, there is a need for photostable compositions containing those agents To prevent ultraviolet inactivation of pesticidal agents, compositions have been prepared which contain ultraviolet absorbers and/or reflectors and a pesticidal agent U S Patent 3,541,203 describes a protected virus composition for insect control The preferred composition includes a virus, an actinic light absorbing material and a polymeric binder material. However, the process used to prepare the preferred compositions of U S Patent 3,541,203 requires the use of toxic materials and numerous washing steps with flammable solvents thus making it unsuitable for commercial manufacture U S Patent 4,948,586 discloses a microencapsulated msecticidal pathogen Four microencapsulated compositions are shown to decrease the photoinactivation of Autographa cahfornica NPV However, the microencapsulated compositions retain only from 30 7 to 71 43% of the original activity upon exposure to sunlight U S Patent 4,948,586 discloses a method of preparing microencapsulated msecticidal pathogens which has numerous steps and is both time-consuming and laborious It is apparent that neither the process, nor the microencapsulated msecticidal ww ^ o g 0 pathogens, described in U S Patent 4,948,586, are entirely-satisfactory for providing a product stable to ultraviolet radiation U S Patent 5,560,909 discloses a process for the preparation of msecticidal compositions which requires the modification of the charge of a charged polymer to precipitate the polymer and entrap the insecticide However, this process is not entirely satisfactory because a small amount of the functional groups on the polymer will remain charged in the final product, resulting m a less efficacious product EP 697170-A1 discloses a process for the preparation of coated pesticidal agents which requires that the coating polymer be completely dissolved and which adjusts the pH of the coating solution to attain such dissolution Unfortunately, such dissolution reduces some of the desirable properties of the coating polymer, resulting in a less efficacious product The present invention comprises a process for the preparation of a coated pesticidal matrix, which process comprises a) preparing an aqueous mixture comprising a pesticidal agent, a pH-dependent polymer ana water, wherein the pH of the aqueous mixture is below the solubilization pH of the pH-dependent polymer; and b) drying the aqueous mixture of step (a) to produce the coated pesticidal matrix The aqueous mixture optionally includes a plasticizer, an ultraviolet protector, an activity enhancer and/or a glidant thus resulting in their presence in the coated pesticidal matrix Preferably, the pesticidal agent is a particulate chemical insecticide or a viral, bacterial or fungal msecticidal pathogen In a further aspect, the present invention provides a coated pesticidal matrix which comprises about 1 to 50% by weight of a pesticidal agent, about 5 to 50% by weight of a pH-dependent polymer wherein a substantial I u/- (V 2 I I 1' Aus m I re£Lfi'/fq I 33 o - number of the free carboxylic acid groups in said polymer have not been converted to their salt form, 0 to about 25% by weight of a plasticizer, 0 to about 30% by weight of an ultraviolet protector, 0 to about 75% by weight of an activity enhancer, and 0 to about 15% by weight of a glidant. In another aspect, the present invention comprises a wettable powder pesticidal composition which comprises about 0 5 to 40% by weight of a dispersing agent, about 1 to 10% by weight of a flow enhancing agent, about 10 to 70% by weight of a bulking agent; 0 to about 25% by weight of a wetting agent; 0 to about 35% by weight of a pH-modifymg agent; and about 5 to 75% by weight of a coated pesticidal matrix of the invention In a still further aspect, the present invention comprises a method for improving the residual control of a pest comprising applying to the locus of the pest a pesticidally effective amount of a coated pesticidal matrix of the invention Objects of the present invention include to provide a coated pesticidal matrix which retains the desirable properties of the coating polymer and thus retains a significant amount of its original pesticidal activity after exposure to ultra-violet radiation; to provide a process for the preparation of a coated pesticidal matrix under mild conditions which avoid degradation of the pesticidal agent; or at least to provide the public with a useful choice. Other objects of this invention will be apparent to those skilled in the art from the following description and the appended claims The process of this invention comprises. a) preparing an aqueous mixture comprising a pesticidal agent, a pH-dependent polymer, optionally a plasticizer, optionally an ultraviolet protector, INTELLECTUAL PROPERTY OFFICE OF NZ 1 1 /,1'3 ID39 allowed by page 3a RECEIVED - 3a - *=*7 vry W OS 76 optionally an activity enhancer, optionally a glidant, and water, provided that the pH of the aqueous mixture is below the solubilization pH of the pH-dependent polymer, and b) drying the aqueous mixture of step (a) to produce a coated pesticidal matrix Advantageously, it has been found that coated pesticidal matrices, prepared from a pH-dependent polymer without converting a substantial number of free carboxylic acid groups m the polymer to their salt form, retain a INTELLECTUAL PROPERTY OFFICE OF NZ 1 I AUG 1999 -4- ACY-33343 17 6 98 high percentage of their original activity after exposure to ultraviolet radiation and have greater residual activity compared to coated pesticidal agents prepared by the coating process described m EP 697170-A1. The instant 5 process accomplishes this by providing an aqueous mixture wherein the pH is below the solubilization pH of the pH-dependent polymer The coated pesticidal matrices of the invention preferably comprise about 1 to 50% by weight of a 10 pesticidal agent, more preferably about 5 to 35% by weight of a pesticidal agent They preferably comprise about 5 to 50% by weight of a pH-dependent polymer, more preferably about 10 to 4 5% by weight of a pH-dependent polymer They preferably comprise about 0 to about 2 5% by weight of a 15 plasticizer, more preferably about 0 to about 25% by weight of a plasticizer. They preferably comprise about 0 to about 30% by weight of an ultraviolet protector, more preferably about 0 to about 20% by weight of an ultraviolet protector. They preferably comprise about 0 to about 7 5% by weight of 20 an activity enhancer, more preferably about 0 to about 45% by weight of an activity enhancer They preferably comprise about 0 to about 15% by weight of a glidant more preferably about 0 to about 10% by weight of a glidant In a preferred embodiment of the present invention, 25 coated pesticidal matrices prepared by the process of this invention comprise about 1 to 50% by weight of a pesticidal agent, about 5 to 50% by weight of a pH-dependent polymer, 0 to about 25% by weight of a plasticizer, 0 to about 3 0% by weight of an ultraviolet protector, 0 to about 75% by 30 weight of an activity enhancer, and 0 to about 15% by weight of a glidant More preferred coated pesticidal matrices prepared by the process of this invention are those comprising about 5 -5- ACY-33343 17 6.98 to 35% by weight of a pesticidal agent, about 10 to 45% by weight of a pH-dependent polymer, 0 to about 25% by weight of a plasticizer, 0 to about 20% by weight of an ultraviolet protector, 0 to about 45% by weight of an 5 activity enhancer, and 0 to about 10% by weight of a glidant. The aqueous mixture of this invention may be dried using any conventional drying technique which allows the pH-dependent polymer to form a coating film on the outside, 10 and a binding film inside, of the matrix particles Preferably, the aqueous mixture is spray dried or air dried. The coated pesticidal matrices of the present invention preferably have a particle size less than about 20 |±m, and, more preferably, have a particle size of about 15 2 |lm to 10 Jim Pesticidal agents suitable for use m the present invention include chemical and biological insecticides, acaricides, nematicides, fungicides, herbicides, and the like, and mixtures thereof. In particular, pesticidal 20 agents which are subject to inactivation of their desired activity by ultraviolet radiation are preferred pesticidal agents for use m this invention Chemical insecticides include, but are not limited to, arylpyrroles such as chlorfenapyr, amidmohydrazones such 25 as hydramethylnon, hydrazmecarboxyamides such as those described m U.S. 5,543,573, 1,4-diaryl-2-fluoro-2-butenes such as those described m EP 811593-A1, including l-[l-(p-chloropheny1)-2-fluoro-4-(4-fluoro-3-phenoxyphenyl)-2-butenyl]cyclopropane, (R,S)-(Z)-, 30 l-substituted-2-(nitromethylene) lmidazolidmes such as lmidacloprid and 1-{6-chloro-3-pyridyl)-2-(nitromethylene) lmidazolidine, phenylpyrazoles such as fipronil, and the like, and mixtures thereof The chemical 1 « V • ACY-33343 17 6 91 -6- msecticides of this invention, when m solid form, preferably have a particle size prior to coating of less than about 10 |iiri and, more preferably, have a particle size of about 0 1 [im to 5 Jim 5 Biological insecticides include all naturally occuring and genetically modified varieties of insect biological control agents such as viral pathogens, bacterial pathogens, and fungal pathogens Viral pathogens suitable for use include DNA viruses, RNA viruses and unclassified 10 insect viruses such as gonad-specific virus (GSV). The DNA viruses include double stranded enveloped DNA viruses such as (Subfamily, then species) Entomopoxvirmae (Melolontha melolontha entomopoxvirus), and Eubaculovirmae (Autographa californica MNPV; Heliocoverpa zea NPV, 15 Trichoplusia ni GV), as well as double stranded nonenveloped DNA viruses such as Iridoviridae (Chilo iridescent virus) and single stranded nonenveloped DNA viruses such as Parvoviridae (Galleria densovirus) The RNA viruses include double stranded enveloped RNA 20 viruses such as Togaviridae (Sindbis virus), Bunyaviridae (Beet leafcurl virus) and Flaviviridae (Wesselbron virus), as well as double stranded nonenveloped RNA viruses such as Reoviridae (Corriparta virus) and Birnaviridae (Drosophila X virus), as well as single stranded nonenveloped RNA 25 viruses such as Picornaviridae (Cricket paralysis virus), Tetravindae (Helxothis armigera stunt virus) and Nodaviridae (Black beetle virus) The Subfamily of double stranded DNA viruses Eubaculovirmae includes two genera, nuclear polyhedrosis 30 viruses (NPVs) and granulosis viruses (GVs), which are particularly useful for biological control because they produce occlusion bodies in their life cycle Examples of NPVs include Lymantria dispar NPV (gypsy moth NPV), ACY-33 343 17 6 98 -7- Autographa californica NPVs such as V8vEGTDEL, V8vEGTDEL-AalT, AcMNPV E2, AcMNPV LI, AcMNPV V8, and AcMNPV Pxl, Anagrapha falcifera NPV (celery looper NPV), Spodoptera littoralis NPV, Spodoptera frugiperda NPV, Heliothis 5 armigera NPV, Mamestra brassicae NPV, Choristoneura fumiferana NPV, Trichoplusia ni NPV, Heliocoverpa zea NPV, and Rachiplusia ou NPV, and the like. Examples of GVs include Cydia pomonella GV (coddling moth GV), Pieris brassicae GV, Trichoplusia ni GV, Artogeia rapae GV, Plodia 10 mterpunctella GV (Indian meal moth) , and the like Examples of entomopox viruses (EPVs) include Melolontha melolontha EPV, Amsacta moorei EPV, Locusta migratoria EPV, Melanoplus sanguinipes EPV, Schistocerca gregaria EPV, Aedes aegypti EPV, Chironomus luridus EPV, and the like 15 Bacterial pathogens suitable for use include, but are not limited to, Bacillus thurmgiensis, Bacillus lentimorbus, Bacillus cereus, Bacillus popilhae, Photorhabdus lummescens, Xenorhabdus nematophilus, and the like Fungal pathogens suitable for use include, but are 20 not limited to, Beauvena bassiana, Entomophthora spp , Metarrhizium anisopliae, and the like. AcMNPV E2 is described m EP 621337, and co-pending U S Serial No 08/009,264, filed January 25, 1993, which is incorporated herein by reference AcMNPV V8 and 25 V8vEGTDEL are described m U S Patent 5,662,897 which is incorporated herein by reference V8vEGTDEL-AaIT is described m EP 697170-A1 and co-pending U S Serial No 08/322,679, filed July 27, 1994 AcMNPV Pxl is described in co-pending provisional U S Serial No 60/084,705, filed 30 May 8, 1998, which is incorporated herein by reference Herbicides suitable for use m the present invention include chemical and biological herbicides Chemical herbicides include, but are not limited to, dinitroanilines -8- ACY-33343 17 6.98 such as pendxmethalin and trifluralin, lmidazohnones such as ima?ethapyr, lmazaqum, imazamethabenz-methyl, imazapyr, imazamox and lmazaoic, haloacetanilides such as alachlor, metolachlor, and propachlor, and the like, and mixtures 5 thereof Biological herbicides include, but are not limited to, fungal pathogens such as a Dactylaria higgmsii, and the like, and mixtures thereof pH-Dependent polymers suitable for use m the present invention include polymers which are essentially insoluble 10 below about pH 5 5, such as ethyl acrylate/methacrylic acid copolymers, methyl methacrylate/methacrylic acid copolymers, methacrylic acid/methyl acrylate/methyl methacrylate copolymers and the like, and mixtures thereof Preferred pH-dependent polymers include ethyl 15 acrylate/methacrylic acid copolymers particularly those wherein the ratio of free carboxyl groups to esters is about 1 1 (Eudragit L 30 D, solubilization pH >5 5, available from Rohm Pharma GmbH, Weiterstadt, Germany, and (S> Kollicoat MAE 30 D, solubilization pH >5 5, available 20 from BASF, Ludwigshafen, Germany), methyl methacrylate/methacrylic acid copolymers particularly those wherein the ratio of free carboxyl groups to esters is from about 1 1 to about 1 2 (Eudragit® S100, 1 2 ratio, solubilization pH > 7.0, available from Rohm Pharma, and 25 Eudragit® L100, 1 1 ratio, solubilization pH > 6 0, available from Rohm Pharma), methacrylic acid/methyl acrylate/methyl methacrylate copolymers particularly those wherein the ratio of methacrylic acid, methyl acrylate and methyl methacrylate monomers is about 1.5 2 to 3 7 3 30 (Preparation 4110D, 1:6 5:2 5 ratio, solubilization pH > 7 2, available from Rohm Pharma), and mixtures thereof The pH-dependent polymer should be essentially insoluble below about pH 5 5 to prevent premature release I ACY-33343 17.6.98 -9- of the pesticide when the coated pesticidal matrix is applied to the locus of a pest In addition, when the pesticidal agent is an insecticide, the pH-dependent polymer is preferably soluble m the envnonment of the 5 insect's gut so that the pesticidal agent may be readily released from the coated pesticidal matrix. Preferably, the pH-dependent polymer should be soluble above about pH 7 to ensure that the pesticide is readily released in the insect's gut 10 In a preferred embodiment of the process of this invention, the methyl methacrylate/methacrylic acid copolymer is partially solubilized with base to reduce agglomeration of the copolymer particles prior to drying However, it should be understood that the amount of base 15 added is well below the amount required to fully solubilize the copolymer Typically, less than about 10% of the free carboxylic acid groups of the copolymer are converted to salts. Bases suitable for use to partially solubilize the methyl methacrylate/methacrylic acid copolymers of this 20 invention include ammonium hydroxide, alkali metal hydroxides, alkaline earth metal hydroxides and the like, with ammonium hydroxide being preferred. Plasticizers may be used m the process of this invention to reduce the minimum film forming temperature of 25 the pH-dependent polymer Plasticizers suitable for use m the present invention include any of the conventional agents known m the art such as poly{ethylene glycols), poly(propylene glycols), diethyl phthalate, dibutyl phthalate, citric acid esters such as triethyl citrate and 30 the like, castor oil, triacetm and the like or mixtures thereof Preferred plasticizers include poly(ethylene glycols) having an average molecular weight of about 1,000 to 10,000 and triethyl citrate i » -10- ACY-33343 17 6 98 Ultraviolet protectors may be used in the present invention to reduce the photoinactivation of the pesticidal agent Ultraviolet protectors suitable for use include ultraviolet absorbers and ultraviolet reflectors or 5 mixtures thereof Ultraviolet absorbers include various forms of carbon, such as carbon black (charcoal), benzophenones, such as 2-hydroxy-4-methoxybenzophenone (CYASORB UV9, available Cfom Cytec Industries, West Paterson, New Jersey), 2,2'-dihydroxy-4-methoxybenzophenone 10 (CYASORB® UV2 4, available from Cytec Industries), 2~ hydroxy-4-acryloyloxyethoxybenzophenone (CYASORB® UV2 09 8, available from Cytec Industries), 2-hydroxy-4-n-octoxybenzophenone (CYASORB UV531, available from Cytec Industries), dyes, such as congo red, malachite green, 15 malachite green hydrochloride, methyl orange, methyl green, brilliant green, acridme yellow, FDC green, FDC yellow, FDC red, and the like Ultraviolet reflectors include titanium dioxide and the like Preferred ultraviolet protectors include carbon black, benzophenones, dyes and 20 titanium dioxide, with titanium dioxide, carbon black, (JO (ft) CYASORB UV9 and CYASORB UV2 4 being most preferred Activity enhancers are used in this invention to enhance pesticidal activity of the pesticidal agent Activity enhancers suitable for use m this invention 25 include fluorescent brighteners described in U S Patent 5,124,149 and stilbene compounds described in U S Patent 5,246,936, both incorporated herein by reference In addition to enhancing pesticidal activity, the stilbene compounds also provide some protection from ultraviolet 30 radiation Preferred stilbene compounds are the analogues of 4,4'-diamino-2,2'-stllbene disulfonic acid, namely, a Calcofluor White (available from Sigma Chemical Co , St Louis, Missouri) such as Calcofluor White M2R, Calcofluor -11- ACY-33343 17 6 98 White ABT, Calcofluor White LD, Calcofluor White RWP, etc., a Blancophor (available from Mobay Chemicals, Pittsburgh, Pennsylvania) such as Blancophor BBH, Blancophor MBBH, Blancophor BHC, etc , an INTRAWITE (a heterocyclic 5 stilbene derivative, available from Crompton and Knowles Corp., Charlotte, North Carolina) such as INTRAWITE CF, etc , a Leucophor (available from Sandoz Chemicals Corp., Charlotte, North Carolina) such as Leucophor BS, Leucophor BSB, Leucophor EKB, Leucophor PAB, etc , a Phorwite 10 (available from Mobay Chemicals) such as Phorwite AR, Phorwite BBU, Phorwite BKL, Phorwite CL, Phorwite RKK, etc and the like Blancophor BBH, Calcofluor White M2R and Phorwite AR are the most preferred stilbene compounds Glidants may be used in the process of this invention 15 to keep the dried, coated pesticidal matrix particles from sticking together In addition, the glidant may also provide some protection from ultraviolet radiation Glidants suitable for use in this invention include talc, magnesium stearate, calcium stearate, calcium sulfate and 20 the like or mixtures thereof, with talc being preferred Other compatible additives such as preservatives, stabilizers (trehalose), anti-foam agents, anti-mold agents, anti-fungal agents, anti-bacterial agents and the like may also be included in the matrices of the present 25 invention Clearly, anti-fungal agents and anti-bacterial agents generally need not be used when fungal pathogens and bacterial pathogens, respectively, are used The compositions of the present invention may be wettable powders comprising one or more dispersing agents, 30 one or more flow enhancing agents, one or more bulking agents, one or more wetting agents and/or one or more pH-modifymg agents Such wettable powders preferably comprise about 2 to 15% by weight of a dispersing agent, -12- ACY-33343 17 6 98 more preferably about 2 to 15% by weight of a dispersing agent and most preferably about 2 to 10% by weight of a dispersing agent They preferably comprise about 1 to 10% by weight of a flow enhancing agent, more preferably about 5 1 to 10% by weight of a flow enhancing agent They preferably comprise about 10 to 60% by weight of a bulking agent, more preferably about 10 to 60% by weight of a bulking agent and most preferably about 20 to 50% by weight of a bulking agent They preferably comprise about 0 to 10 about 15% by weight of a wetting agent, more preferably about 0 to about 15% by weight of a wetting agent They preferably comprise about 0 to about 20% by weight of a pH-modifymg agent, more preferably about 0 to about 20% by weight of a pH-modifying agent and most preferably about 2 15 to 20% by weight of a pH-modifying agent They preferably comprise about 5 to 75% by weight of a coated pesticidal matrix prepared by the process of this invention, more preferably about 5 to 75% by weight of a coated pesticidal matrix prepared by the process of this invention and most 20 preferably about 15 to 60% by weight of a coated pesticidal matrix The present invention also provides wettable powder pesticidal compositions which comprise about 0 5 to 40% by weight of a dispersing agent, about 1 to 10% by weight of a 25 flow enhancing agent, about 10 to 70% by weight of a bulking agent, 0 to about 25% by weight of a wetting agent, 0 to about 35% by weight of a pH-modifying agent; and about 5 to 75% by weight of a coated pesticidal matrix prepared by the process of this invention 30 Preferred wettable powder pesticidal compositions of the present invention are those comprising about 2 to 15% by weight of a dispersing agent, about 1 to 10% by weight of a flow enhancing agent, about 10 to 60% by weight of a -13- ACY-333 43 17 6 98 bulking agent, 0 to about 15% by weight of a wetting agent, 0 to about 20% by weight of a pH-modifying agent, and about 5 to 75% by weight of a coated pesticidal matrix prepared by the process of this invention 5 When the pesticidal agent is a biological agent, the wettable powder compositions of this invention preferably comprise about 2 to 10% by weight of a dispersing agent, about 1 to 10% by weight of a flow enhancing agent, about 10 20 to 50% by weight of a bulking agent, about 2 to 20% by weight of a pH-modifying agent, and about 15 to 60% by weight of a coated biological agent matrix prepared by the process of this invention Dispersing agents useful in the wettable powder 15 pesticidal compositions of this invention include any of the conventional agents known in the art Preferred dispersing agents are anionic agents, such as salts of the condensation products of formaldehyde with the sulfonation products of polycyclic aromatic compounds, sodium 20 lignosulfonate and the like or mixtures thereof with the sodium sulfonate of naphthalene formaldehyde condensates such as MORWET® D425 (available from Witco) , LOMAR® PW (available from Henkel, Ambler, Pennsylvania) and DARVAN 1 (available from R T. Vanderbilt Co , Norwalk, Connecticut) 25 being most preferred Flow enhancing agents useful in the wettable powder pesticidal compositions of this invention include conventional flow enhancing agents known in the art with silicates such as calcium silicates being preferred 30 MICRO-CEL E (a synthetic calcium silicate hydrate available from Celite Corp , Lompoc, California) is the most preferred flow enhancing agent ACY-33343 17 6 98 -14- Bulkmg agents suitable for use m the compositions of the present invention include natural and synthetic clays and silicates, e g , natural silicas such as diatomaceous earths, magnesium silicates such as talcs, 5 magnesium aluminum silicates such as attapulgites and ventriculites, aluminum silicates such as kaolinites, montmorillonites and micas, and hydrated aluminum silicates such as kaolin clay Preferred bulking agents are hydrated aluminum silicates, aluminum silicates, magnesium silicates 10 and magnesium aluminum silicates, with kaolin clay being the most preferred bulking agent Wetting agents suitable for use in the present invention include any of the conventional agents known m the art Preferred wetting agents include anionic agents 15 such as sodium N-methyl-N-oleoyltaurate, octylphenoxy polyethoxy ethanol, nonylphenoxy polyethoxy ethanol, sodium dioctyl sulfosuccinate, sodium dodecyl benzene sulfonate, sodium lauryl sulfate, sodium alkyl naphthalene sulfonate, sodium sulfonated alkyl carboxylate and the like or 20 mixtures thereof A mixture of sodium alkyl naphthalene sulfonate and sodium sulfonated alkyl carboxylate (MORWET EFW available from Witco, Houston, Texas) is a highly preferred wetting agent pH-Modifymg agents are used to maintain the pH of 25 aqueous tank-mixes prepared from the compositions of this invention below about pH 5 pH-Modifymg agents suitable for use include, but are not limited to, potassium hydrogen phthalate, and solid organic acids such as citric acid, glutamic acid, maleic acid, d, 1-malic acid, glutaric acid, 30 isophthalic acid, succinic acid, fumaric acid, adipic acid, and the like, and mixtures thereof Citric acid is especially useful as the pH-modifying agent in the compositions of this invention In the compositions of -15- ACY-33343 17 6 98 this invention, it is preferable to use a granular organic acid having a mean particle size greater than about 50 |Hn, preferably greater than about 100 |im The use of a granular organic acid improves the storage stability of the 5 wettable powder compositions of this invention when compared to wettable powder compositions containing a micronized organic acid The wettable powder pesticidal compositions of the present invention are typically prepared by blending a 10 mixture of a dispersing agent, a bulking agent, a flow enhancing agent, optionally a wetting agent and optionally a pH-modifying agent to form a premix This premix is then blended with the coated pesticidal matrix to form the desired wettable powder pesticidal compositions of the 15 present invention For the control of pests, the wettable powder pesticidal compositions of this invention are diluted with water to form an a ueous tank-mix and the tank-mix is applied to the locus of the pest 20 Surprisingly, it has been discovered that the coated pesticidal matrices of this invention provide improved residual control of pests when compared to coated pesticidal agents prepared according to the aqueous coating process described m EP 697170-A1 Accordingly, the 25 present invention provides a method for improving the residual control of a pest by applying to the locus of the pest a pesticidally effective amount of a coated pesticidal matrix prepared by the process of this invention Other ingredients such as attractants, stickers, anti-30 foaming agents and the like may also be added to the wettable powder compositions of this invention However, those additional ingredients are generally added separately -16- ACY-33343 17 6 98 to the tank-mix An adjuvant or mixture of adjuvants may also be added to the tank-mix In order to facilitate a further understanding of the invention, the following examples are presented primarily for the purpose of illustrating more specific details thereof The invention should not be deemed limited thereby except as defined m the claims -17- ACY-33343 1/ 6 98 EXAMPLE 1 Preparation of coated pesticidal matrices using an ethvl acrvlate/methacrvlic acid copolymer 5 A mixture of V8vEGTDEL polyhedral inclusion bodies (PIBs) (12 43 g of technical material, 7 5 g of PIBs, about 1 27 x 10U PIBs/gram, mean PIB size about 2 5 |lm) , water (65 02 g), Blancophor BBH (28 04 g, mean particle size about 1 Jim) , PEG 5000 (poly (ethylene glycol) average MW 10 5000, 14 0 g of a 10 wt/wt% solution), and Kollicoat® MAE 30 D (46 71 g) is stirred to obtain a slurry The slurry is filtered through an 80 mesh screen and spray dried using a Buchi spray drier (model 190) to obtain the coated pesticidal matrix identified as composition 1 m Table II 15 Using essentially the same procedure, but using the ingredients listed m Table I, the coated pesticidal matrices identified as compositions 2-17 m Table II are prepared -18- ACY-33343 17 6 98 TABLE I Pesticidal Acrent a V8vEGTDEL polyhedral inclusion bodies 5 b V8vEGTDEL-AaIT polyhedral inclusion bodies c Hydramethylnon d Bacillus thuringiensis 10 Ethvl Acrvlate/Methacrvlic Acid Copolymer e Kollicoat® MAE 30 D f Eudragit L 30 D 15 Plasticizer g PEG 5000 h PEG 8000 20 Stilbene Compound l Blancophor BBH 3 Calcofluor M2R 25 UV-Protector k Titanium dioxide 1 Charcoal 30 Additional Compound m Antifoam A (a polydimethylsiloxane and silica antifoam agent available from Dow Corning, Midland, Michigan) « Composition 1 2 3 4 5 6 7 8 9 Pesticidal Agent a/11 25 a/12 23 a/12 25 a/16 19 a/20 38 a/33 31 a/16 00 a/13 30 a/20 55 TABLE II Pesticidal Matrices Ingredient / wt/wt% .Copolymer e/28 62 f/23 30 f/18 37 f/20 96 f/26 38 f/43 11 f/20 71 f/17 22 f/25 74 Compositions may contain a small amount of res'dual water Plasticizer g/2 86 g/2 33 h/1 19 h/1 50 h/2 45 h/2 36 h/1 96 h/1 49 Stilbene Additional Compound UV - Protector Compound i/57 27 i/62 14 i/69 39 1/61 65 j/21 13 i/60 93 i/25 32 k/51 73 k/42 20 k/52 22 0 1 > n i CaJ OO -t^ c> o oo Pesticidal Cpmpqgnipn Agent 10 a/16 11 11 a/12 22 12 a/13.90 13 a/21 28 14 b/14 16 15 b/15 06 16 17 c/13 95 d/14.15 9 TABLE II fconU Ingredient / wt/wt0/)1 Stilbene Additional Copolymer Plasticizer Compound UV- Protector Compound f/20 44 g/2.05 1/61.40 f/23 29 g/2 33 i/62 16 f/26 52 g/2 62 i/49 93 I/7 02 f/1917 g/1 92 1/57 64 - - o f/27 05 g/2 13 i/56 66 e/22 77 g/2 23 i/59.94 > f/27 91 g/2 33 i/55 81 - - 3 Co OJ f/27 02 g/2 06 i/56 61 - m/0 16 " t—» VJ O vD CO -21- ACY-33343 17 6 98 EXAMPLE 2 Preparation of coated pesticiddl matrices using a methvl methacrylate/methacrylic acid copolymer A slurry is prepared by sequentially mixing V8vEGTDEL 5 polyhedral inclusion bodies (13 0 g of technical material, 6 0 g of PIBs, about 1 27 x 1011 PIBs/gram, mean PIB size about 2 5 |lm) , water, 56 6 g of a copolymer slurry (previously prepared by mixing Eudragit S100 (30 0 g), water (166 g), IN ammonium hydroxide solution (15 24 g) 10 and triethyl citrate (15 0 g)), Blancophor BBH (14 0 g), talc (3 21 g), charcoal (9 0 g), a solution of Calcofluor M2R (14.0 g) m water, and water The resultant slurry is then filtered through an 80 mesh screen and spray dried using a Buchi spray drier (model 190) to obtain the coated 15 pesticidal matrix identified as composition 18 m Table IV. Using essentially the same procedure, but using the ingredients listed m Table III, the coated pesticidal matrices identified as compositions 19-26 m Table IV are prepared ACY-33343 17 6 98 -22-TABLE III Pesticidal Aaent a V8vEGTDEL polyhedral inclusion bodies 5 b V8vEGTDEL-AaIT polyhedral inclusion bodies c Yeast Methvl Methacrvlate/Methacrvlic Acid Copolymer dD d Eudragit S100 10 e Eudragit L100 Plasticizer f Triethyl citrate 15 UV-Protector g Charcoal Stilbene Compound h Blancophor BBH 20 i Calcofluor M2R G1idant j Talc 25 Additional Compound k Citric acid 1 Microat afa Complex (an antioxidant available from Nurture Inc , Missoula, Montana) TABLE IV Pesticidal Matrices Ingredient / wt/wr/o1 Pesticidal Stilbene Additional Composition Aaent Copolymer Plasticizer UV-Protector Compound Glidant Compound 18 a/1189 d/14 86 f/7 43 g/17 84 h/27 75 j/6 36 i/13 87 19 a/11.89 d/14 86 f/7 43 g/17 84 h/35 08 j/6 36 I/6 54 20 a/12 36 e/15 45 f/7 72 g/18 54 h/37 08 j/7.72 k/1 13 21 a/12 12 e/1515 f/7 58 g/18 18 h/36 36 j/7 58 k/1.01 I/2.02 22 b/10 90 d/16 59 f/8 30 g/16 59 h/38.06 j/5 20 1/4 36 23 b/8 68 d/17.59 f/8.81 g/16 77 h/38 47 j/5 26 1/4 41 I to I n 24 b/8 77 d/16.94 f/8 47 g/17 20 h/38 86 j75 31 - ~ i/4 45 25 a/10.90 d/16 59 f/8 30 g/16 59 h/38 06 j/5 20 i/4 36 u> oo UJ O 26 c/21 61 e/40 36 - - h/38 04 » 1 Compositions may contain a small amount of residual water -24- ACY-33343 17 6 98 EXAMPLE 3 Preparation of coated pesticidal matrices using a methacrylic acid/methvl acrvlate/methvl methacrylate copolymer 5 A mixture of chlorfenapyr (3 00 g, mean particle size about 2 5 |im) , water (100.00 g) , Blancophor BBH (12 00 g, mean particle size about 1 |im) , triethyl citrate (0 23 g) , a 20% solution of Preparation 4110D (22.50 g), talc (3 00 ®) g), and MORWET D425 (1 50g) is stirred to obtain a slurry 10 The slurry is filtered through an 80 mesh screen and spray dried using a Buchi spray drier (model 19 0) to obtain the coated pesticidal matrix identified as composition 27 m Table VI Using essentially the same procedure, but using the 15 ingredients listed in Table V, the coated pesticidal matrices identified as compositions 28-32 m Table VI are prepared. ACY-33343 17 6 98 -25- TABLE V Pesticidal Agent 5 a Chlorfenapyr b Hydramethylnon c 1-(6-Chloro-3-pyridyl)-2-(nitromethylene)imidazolidine d V8vEGTDEL-AaIT polyhedral inclusion bodies 10 Methacrylic Acid/Methvl Acrvlate/Methvl Methacrylate Copolymer Preparation 4110D Plasticizer 15 Triethyl citrate Stilbene Compound e Blancophor BBH f Calcofluor M2R 20 UV-Protector Charcoal G1idant 25 Talc Additional Compound MORWET D4 25 TABLE VI Pesticidal Matrices Ingredient/wt/wt% Pesticidal Preparation Triethyl Stilbene Composition Agent 4110D Citrate Compound 27 a/12 38 18 57 0 95 e/49 53 28 a/9 01 18.02 0.90 e/36.04 f/9 01 29 b/12 38 18 57 0.95 e/49 53 30 b/9 01 18 02 0 90 e/36 04 f/9 01 31 c/13 97 21 12 1 05 e/42 76 32 d/9 36 18 71 1.87 e/37.42 f/4 57 'Compositions may contain a small amount of residual water. Charcoal Talc MORWETgD425 13 51 13 51 18.71 12 38 9 01 12 38 9 01 13.97 9 36 6 19 4 50 6.19 4 50 713 -27- ACY-33343 17 6 98 EXAMPLE 4 Preparation of a coated pesticidal matrix using a methyl methacrylate/methacrylic acid copolymer. RE AX 85A and Indulm C A mixture of V8vEGTDEL polyhedral inclusion bodies (13 0 g of technical material, 6 0 g of PIBs, about 1 27 x 1011 PIBs/gram, mean PIB size about 2 5 |J.m) and ammonium hydroxide solution (15 0 g, pH 9 5) is stirred for 15 (E> minutes, treated with REAX 85A (0 18 g, a sodium lignosulfonate available from Westvaco, Charleston Heights, South Carolina), stirred for 15 minutes, treated with <B) Indulm C (12 0 g of a 2% solution, pH 11, a sodium lignate available from Westvaco), stirred for one hour, and adjusted slowly to pH 4 5 with dilute sulfuric acid over 2 5 hours After stirring for 45 minutes, the polyhedral inclusion body mixture is mixed with the copolymer slurry described in Example 2 (56 6 g), Blancophor BBH (14 70 g), talc (3 21 g), charcoal (9 0 g), a solution of Calcofluor M2R (3.30 g) m water, and water to obtain a slurry The slurry is filtered through an 80 mesh screen and spray dried using a Buchi spray drier (model 190) to obtain the coated pesticidal matrix identified as composition 33 in Table VII -28- ACY-33343 17 6 98 TABLE VII Composition 33 Inaredient wt/wt% V8vEGTDEL polyhedral inclusion bodies 12 53 Eudragit® S100 15 66 Triethyl citrate 7 83 Charcoal 18 80 Blancophor BBH 3 0 7 0 Calcofluor M2R 6.89 Talc 6 70 00 Indulm C 0.50 fib REAX 85A 0 38 5 EXAMPLE 5 Preparation of wettable powder pesticidal compos11 i ons The coated pesticidal matrix identified as composition 10 18 in Table IV (23 13 g) is added to a premix of MORWET® EFW (3.84 g), MORWET® D425 (7 68 g), kaolin clay (23.03 g), fl?) MICRO-CEL E (2 30 g), and citric acid (11 52 g) The resultant mixture is blended to obtain the wettable powder composition identified as composition 34 m Table VIII 15 Using essentially the same procedure, the wettable powder compositions identified as compositions 35-53 in Table VIII are prepared TABLE VIII Wettable Powder Pesticidal Compositions ingredient! v/\Jv/t% Coated Pesticidal Composition Matrix1 MORWET3 EFW MORWET* D425 Kaolin Clav MICRO-CELsE Citric Acid 34 18/32.35 5.37 1074 3221 3.22 16 112 35 1/30 77 5 50 10 99 32.97 3 30 16 482 36 2/25 91 5 88 11 76 35 29 3 53 17.63* 37 9/16 05 6 67 13 32 39 98 4.00 19.99* 38 11/25 91 5 88 11 76 35 28 3 53 17.642 39 12/16 98 7 56 15 11 49 81 4 98 5 56* 40 13/19 80 6 37 12 73 38 20 3 82 19 092 41 15/21.52 713 14 30 4710 4 70 5 252 42 19/32 35 5 37 10 74 32.21 3 22 16 112 43 20/31.12 5.47 10 94 32 79 3 28 16 402 44 21/31 73 5 42 10 84 32 50 3 25 16.25* coated pesticidal matrix is identified by the n particle size about 1-3 jjm 3 Mean particle size greater than about 100 pm. ' The coated pesticidal matrix is identified by the composition number from Tables II, IV or VI. 1 Mean particle size about 1-3 jjm TABLE Vlll fCont.1 Ingredient/ wt/wt% Coated Pesticidal Composition Matrix1 45 46 47 48 49 50 51 52 53 22/30 70 22/33 47 22/32 79 23/31 94 25/33 86 27/43.86 28/60 42 31/38 76 32/42 80 MORWET3 EFW MORWET5 D425 Kaolin Clay MlCRO-CELgE Cttrlc Acid 5 50 5 70 5 34 5 52 6 02 5 11 3 60 5 00 11 00 11 40 10 67 11 04 12 04 10 22 7 20 10 00 3 00 32 99 36 16 32 01 36 39 39 68 33 68 23 75 32.94 37 20 3 30 3 61 3 20 3 64 3.97 3 37 2 37 3 30 6.00 16 50' 9 662 16 007 11.472 4 43' 3 76* 2 65* 10 003 11.003 1 The coated pesticidal matrix is identified by the composition number from Tables II, IV or VI 2 Mean particle size about 1-3 (jm 3 Mean particle size greater than about 100 pm ACY-33343 17 6 98 -31- EXAMPLE 6 Evaluation of wettable powder pesticidal compositions of this invention and a wettable powder pesticidal composition disclosed in EP 697170-A1 5 against tobacco budworms Wettable powder compositions 34, 36, 37 and 43, and a control composition, identified below, are tested for efficacy against neonate tobacco budworms, H virescens, on cotton variety IAC-22 through bioassay of field-treated 10 foliage Each composition is mixed with water, 0 2 w/v% KINETIC (nonionic surfactant mixture available from Helena Chemical Co , Memphis, Tennessee), and 3 5 w/v% MIRASPERSE (2-hydroxypropyl ether starch available from A E. Staley Manufacturing Co , Decatur, Illinois). In addition, 0 1 15 w/v% citric acid is added to the aqueous control composition Treatments are applied with a C02 backpack sprayer calibrated to deliver 200 L/ha using 2 ft boom with hollow-cone nozzles (3/row, 1 centered and 2 drop) For bioassay, leaves are collected 1-2 hours following 20 application for initial activity and 1, 2, 3, and 4 days after treatment for residual activity. The treated leaves are placed in petn dishes with moist filter papers (1 leaf/dish, 4 larvae/dish, 16 dishes/treatment with a total of 64 larvae/treatment/sampling period). After allowing 25 the larvae to feed on the treated leaves for four days, they are transferred to diet trays containing pieces of untreated cotton leaves, one larva/cell. After 4 days, the surviving larvae are counted The results are summarized m Table IX 30 As can be seen from the data in Table IX, compositions containing coated pesticndal matrices prepared by the process of the present invention, in general, have greater residual activity against H virescens than the control -32- ACY-333 43 17 6 98 composition prepared by the aqueous process described in EP 697170-A1 In particular, composition 34 has significantly greater residual activity than the control composition This is an especially surprising discoveiy because the 5 copolymer used in composition 34 and the control composition is the same Eudragit S100 Control Composition Inoredient wt/wt% boated pesticidal agent 2 5 14 MORWET EFW 5 94 MORWET D425 11 89 Kaolin Clay 3 5 64 rt?\ MICRO-CEL E 3 56 Citric Acid 17 83 Prepared according to the aqueous process described in EP 697170-A1 The coated pesticidal agent contains 15 31 10 wt/wt% V8vEGTDEL polyhedral inclusion bodies, 15 31 wt/wt% Eudragit S100, 0 43 wt/wl% PEG 8000, 23 04 wt/wt% charcoal and 45 92 wt/wt% Blancophor BBH TABLE IX Percent Mortality of H. virescens 15 on Cotton variety IAC-22 Days After Treatment Treatment 0. 1 2. 3. 4_ Composition 3 4 100 92 95 89 75 Composition 3 6 98 97 77 75 66 Composition 3 7 97 94 92 77 67 Composition 4 3 98 95 95 86 80 Control composition 95 86 83 73 69 Untreated 5 2 5 8 6 -33- ACY-33343 17 6 98 EXAMPLE 7 Evaluation of wettable powder pesticidal compositions against tobacco budworms on cotton and lettuce 5 Compositions 3 9 and 49 from Table VIII are tested for efficacy against neonate tobacco budworms, Hehothis virescens, on lettuce variety Green-Towers and cotton variety Delta-Pine 51 through bioassay of field-treated foliage The plots are strips of cotton and lettuce (ca 10 40 ft long) with 3 ft row spacing Each composition is mixed with water and applied at 8 x 1011 polyhedral (£> inclusion bodies/acre DIPEL 2X (Bacillus thurmgiensis var. Kurstaki, available from Abbott Laboratories, North Chicago, Illinois) is applied at 1 0 lb product/acre as a 15 standard Treatments are applied with a C02 backpack sprayer calibrated to deliver 20 gallons per acre using a 2 ft boom with hollow-cone nozzles (3/row, 1 centered and 2 drop) Tor bioassay, leaves are collected 1-2 hours following 20 application for initial activity and 2, 3, 4 and 5 days after treatment for residual activity The treated leaves are placed m petri dishes with moist filter papers (1 leaf/dish, 4 larvae/dish, 16 dishes/treatment with a total of 64 larvae/treatment/sampling period) After allowing 25 the larvae to feed on the treated leaves for two days, they are transferred to diet trays, one larva/cell The surviving larvae are also counted at 2, 4, 6 and 8 days after transfer to diet The results are summarized in Tables X and XI 30 As can be seen from the data m Tables X and XI, the pesticidal compositions of this invention (compositions 39 and 49) have greater residual activity against tobacco <5) budworms after 4, 6 and 8 days on diet than DIPEL 2X -34- ACY-33343 17 6 98 TABLE X Percent Mortality of Day s After Tobacco Budworms oil Cotton Days After Treatment Trea tment Trans f e r to Dxet 0. 2. 1 4. 5. Composition 39 0 4 3 2 1 2 2 24 9 6 3 4 4 49 23 14 6 13 6 50 27 16 7 15 8 51 27 16 8 15 Composition 49 DIPEL® 2X 0 2 3 2 52 17 4 90 57 6 91 59 8 91 59 0 29 9 2 37 13 4 56 14 6 56 14 8 56 14 2 0 5 9 7 6 29 11 14 31 15 16 33 16 16 6 2 4 7 4 6 10 4 6 12 5 6 12 5 6 Untreated 0 12 112 2 1 4 2 3 4 4 2 6 3 3 5 6 2 6 4 3 5 8 2 6 4 3 5 5 -35- ACY-33343 17 6 9 TABLE XI Percent Mortality of Tobacco Budworms on Lettuce Days After Days After Treatment Treatment Transfe r t o Diet 0. 2 3. 4. 5_ Composition 39 0 27 5 2 5 1 2 72 36 16 20 11 4 94 84 62 55 50 6 95 85 67 59 52 8 95 86 67 60 52 Composition 49 DIPEL 2X 0 16 3 2 73 24 4 98 88 6 99 88 8 99 88 0 100 53 2 100 70 4 100 70 6 100 70 8 100 70 7 1 6 23 18 16 78 62 55 85 62 58 85 62 59 42 45 29 50 57 35 56 58 37 56 58 38 56 58 38 Untreated 0 2 12 2 4 2 2 2 5 2 6 4 4 5 6 3 9 6 4 5 6 4 10 8 4 5 6 6 10 -36- ACY-33343 17 6 98 EXAMPLE 8 Evaluation of non-irradiated and irradiated wettable powder compositions against Heliothis virescens Plastic bioassay trays containing 32 open-faced wells (4x4x25 cm, L x W x H) per tray are utilised as test arenas m this evaluation Five mL of Stoneville diet (soybean/wheat germ) is poured into each well and allowed to harden Aqueous suspensions of the wettable powder pesticidal compositions are evenly spread over the surface of the hardened diet to provide 2 x 103 V8vEGTDEL polyhedral inclusion bodies per well Half of the trays are placed under ultraviolet lamps (two FS40UVB bulbs set 30 cm above the trays, Atlantic Ultraviolet Corp , Bay Shore, NY) for four hours All trays are then infested with one three-day-old H virescens larva per well. The wells are covered with a vented, clear plastic sheet and held under constant fluorescent light at a temperature of about 27 °C After ten days, the wells are examined and larval mortality measurements are made The results are summarized m Table XII Advantageously, the wettable powder pesticidal compositions of this invention (composition numbers 35, 36, 38 and 40) retain at least 73 percent of their original activity after being exposed to ultraviolet light for 4 hours -37- ACY-33343 17 6 98 TABLE XII Evaluation Of Non-Irradiated and Irradiated Wettable Powder Pesticidal Compositions Against if. Virescens Wettable Powder Irradiation Percent Larval Composition1 Exposure (hours) Mortalitv 35 0 98 4 74 36 0 98 4 80 38 0 97 4 75 40 0 97 4 71 1 Composition number from Table VIII -38- ACY-33343 17 6 98 EXAMPLE 9 Field evaluation of wettable powder pesticidal compositions against tobacco budworms on tobacco m North Carolina 5 A field evaluation is conducted on tobacco grown near Clayton, North Carolina A wettable powder composition of this invention (composition 46) at 2 x 1011, 5 x 1011, and 8 x 1011 bodies/acre, Bacillus thurmgiensis (DIPEL® 2X, Abbott Laboratories) at 1 0 lb wettable powder (WP)/acre, 10 and acephate (ORTHENE® 75SP, available from Valent USA, Walnut Creek, California) at 0 75 lb active ingredient (ai)/acre are compared for efficacy against H virescens Biological materials are suspended m water containing an (e) insect gustatory stimulant (PHEAST available from 15 AGRISENSE, Fresno, California), aqueous dilutions of (s> acephate contained no PHEAST Treatments and untreated check are replicated four times (small plots) in a randomized complete block design By using fine-hair brushes, 1- to 2-day old laboratory-reared H virescens are 20 placed on the underside of leaves in each plot Natural infestation of H virescens also occurred at the test site Treatments are applied to tobacco about 2 hours before each artificial larval infestation on days 1 and 8 Treatments are applied with a tractor-mounted, C02-pressurized boom 25 sprayer which is calibrated to deliver 25 gallons/acre through a single D2-33 nozzle centered over each tobacco 2 row Boom pressure during application is 60 lb/in At 2 and 5 days after first application and 5 and 9 days after second application, live H virescens are 30 counted on 20 plants m each plot Additionally, visual estimate of leaf damage caused by larval feeding is made 14 days after the second application using the rating scale shown below The results are summarized in Table XIII -39- ACY-3 33 43 17.6 98 Rating Scale Rating Meaninq 4 Severe Damage 3 Heavy Damage 2 Moderate Damage 1 Slight Damage 0 No Damage As can be seen from the data m Table XIII, the wettable powder composition of this invention (composition 46) provides good control of H. virescens on tobacco In fact, on day 17 of the test, the invention composition provides greater control of H virescens than DIPEL® 2X and acephate TABLE XIII Field Evaluation of Wettable Powder Compositions - North Carolina Mean Number of Live Larvae per 20 Plants Mean Plant Day of Test Injury on Day Treatment Pate 3 8 13 1Z 22 of Test Composition 46 2x10" bodies/acre 7 8 6 2 1.8 0.5 0.4 5x10" bodies/acre 68 62 1 2 02 03 8 x 10" bodies/acre 7.0 6.0 1 0 05 0.3 DIPEL® 2X 1 0 lb of WP/acre 55 50 1 2 25 0 1 Acephate 0 75 lb of ai/acre 60 58 1 2 08 02 Untreated 11.2 82 88 90 1 8 -41- ACY-3334 3 17 6 98 EXAMPLE 10 Field evaluation of wettable powder pesticidal compositions against tobacco budworms on tobacco m Georgia 5 A field evaluation is conducted on flue-cured tobacco (var K-236) grown near Tifton, Georgia A wettable powder composition of this invention (composition 47) at 2 x 10u, 5 x 1011, and 8 x 1011 bodies/acre, Bacillus thurmgiensis (DIPEL 4L, available from Abbott Laboratories) at 1 0 10 pint/acre, and methomyl (LANNATE® 2 4L, available from DuPont, Wilmington, Delaware) at 0 6 lb active ingredient (ai)/acre are compared for efficacy against H virescens Biological materials are suspended m water containing an insect gustatory stimulant (COAX available from CCT Corp , 15 Carlsbad, California) at 2 0 pints/acre, aqueous dilutions of methomyl contained no COAX® Treatments and untreated check are replicated four times m a randomized complete block design A treatment replicate consists of a five-row by 20 ft plot of tobacco Treatments are applied to 20 tobacco on days 1, 5, 9, 17 and 22 of the test Treatments are applied with a backpack, C02-pressurized boom sprayer which is calibrated to deliver 20 7 gallons/acre through three TX12 (Spraying Systems, Wheaton, IL) hollow-cone nozzles per row (one nozzle above center of the row and one 25 nozzle directed at each of the two sides of the row) Boom 2 pressure during application is 40 lb/in On days 5, 8, 12, 22, 26 and 29 of the test, live H virescens are counted on 2 0 plants in each plot The results are summarized in Table XIV 30 As can be seen from the data m Table XIV, the wettable powder composition of this invention (composition 47) provides good control of H virescens TABLE XIV Field Evaluation of Wettable Powder Compositions - Georgia Mean Number of Live Larvae per 20 Plants Day of Test Treatment Pate 5 8 12 22 26 29 Composition 47 2x10" bodies/acre 43 1 8 0.5 33 1.0 1 3 5x10" bodies/acre 23 2 0 00 4.5 28 03 8 x 1011 bodies/acre 1 5 0 0 0 0 5 8 1.3 0.3 DIPEL® 4L 1 0 pint/acre 3 8 1.5 08 43 1 5 1 3 Methomyl 0.6 lb ai/acre 1 5 0 5 05 63 2.0 03 Untreated 4 8 2 8 08 70 43 28 -43- ACY-33343 17 6 98 EXAMPLE 11 Evaluation of UV stability of wettable powder compositions comprising chlorfenapvr Wettable powder compositions 50 and 51 from Table VIII, and a control composition identified below are evaluated for UV stability An aqueous suspension of each test composition is applied to plastic petri dishes (100 mm x 15 mm) using a belt sprayer with nozzles calibrated to provide 400 1/ha The test materials are applied at rates to provide the equivalent of 0 5, 1.0 and 5 0 g of chlorfenapyr per hectare The dishes are dried and exposed to UV light using either a UV-B lamp (280-315 nm) or natural light for various periods of time Three second-mstar tobacco budworm larvae (Heliothis virescens) are then placed m each dish and the dishes are covered After holding the dishes at 26 7°C for 48 hours, the surviving larvae are counted The results are summarized m Tables XV and XVI As can be seen from the data m Tables XV and XVI, chlorfenapyr treatments made with the wettable powder compositions of this invention are significantly more stable to UV exposure than the control composition which does not incorporate chlorfenapyr into a pesticidal matrix ACY-33343 17 6 98 -44- Control Composition Ingredient wt/wt% Chlorfenapyr (tech ) 5 43 MORWET®EFW 8 60 MORWET D4 25 17 21 Kaolin Clay 56 75 MIRO-CEL E 5 67 Citric Acid1 6 34 1Mean particle size about 1- 3 J-lm TABLE XV Evaluation of UV (natural light) Irradiated Chlorfenapyr Wettable Powder Coinpositions Wettable Irradiation Percent Larval Powder Expo sure(day Mortality Composition s ) 1 0 g/ha 0 .5 g/ha 50 0 100 86 2 74 58 3 28 34 51 0 100 91 2 100 75 3 63 48 Control Composition 0 100 97 2 3 54 15 34 22 </div>

Claims

<div class="application article clearfix printTableText" id="claims"> -45- ACY-3 334 3 17 6.98 TABLE XVI Evaluation of UV-B Lamp Irradiated Chlorfenapyr Wettable Powder Compositions Wettable Irradiation Percent Larval Powder Exposure(hour Mortality Compos ition s ) 5.0 g/ha 1 0 g/ha 50 0 100 100 8 100 76 22 100 76 37 100 0 51 0 100 100 8 100 47 22 100 21 37 56 0 Control Composition 0 100 100 8 100 31 22 100 24 37 14 6 -46- ACY-33 3 43 17 6 98 WHAT WE CLAIM IS: 1. A process for the preparation of a coated pesticidal matrix which process comprises a) preparing an aqueous mixture comprising a pesticidal agent, a pH-dependent polymer and water, provided that the pH of the aqueous mixture is below the solubilization pH of the pH-dependent polymer, and b) drying the aqueous mixture of step (a) to produce the coated pesticidal matrix 2 A process as claimed m Claim 1 wherein one or more of a plasticizer, an activity enhancer and an ultraviolet protector is included m the aqueous mixture 3. A process as claimed m Claim 1 or Claim 2 wherein the pesticidal agent is selected from the group consisting of an insecticide, an acaricide, a nematicide, a fungicide and a herbicide and mixtures thereof 4 A process as claimed in any one of Claims 1 to 3 wherein the pesticidal agent is a chemical or a biological insecticide 5 A process as claimed m any one of Claims 1 to 3 wherein the pesticidal agent is a chemical insecticide selected from the group consisting of chlorfenapyr, hydramethylnon, lmidacloprid, 1-(6-chloro-3-pyridyl)-2-(nitromethylene)imidazolidine, fipronil, and l-[l-(p-chlorophenyl)-2-fluoro-4-(4-fluoro-3-phenoxyphenyl)-2-butenyl]cyclopropane, (R,S)-(Z)-, and mixtures thereof -47- ACY-33343 17 G 98 6 A process as claimed in any one of Claims 1 to 5 wherein the pesticidal agent is a biological insecticide selected from the group consisting of V8vEGTDEL, V8vEGTDEL-AalT, Heliothis zea NPV, Lywantria dispar NPV, AcMNPV E2, AcMNPV LI, ACMNPV V8, AcMNPV Pxl, and Bacillus thurmgiensis, and mixtures thereof 7 A process as claimed in any one of Claims 1 to 6 wherein the pH-dependent polymer is selected from the group consisting of an ethyl acrylate/methacrylic acid copolymer, a methyl methacrylate/methacrylic acid copolymer, a methacrylic acid/methyl acrylate/methyl methacrylate copolymer, and mixtures thereof, the plasticizer is selected from the group consisting of a poly(ethylene glycol), a poly(propylene glycol), a citric acid ester, diethyl phthalate, dibutyl phthalate, castor oil, triacetin, and mixtures thereof, the ultraviolet protector is selected from the group consisting of carbon black, a benzophenone, a dye, titanium dioxide, and mixtures thereof, the activity enhancer is a stilbene compound, and the glidant is selected from the group consisting of talc, magnesium stearate, calcium stearate, calcium sulfate, and mixtures thereof 8 A process as claimed in any one of Claims 1 to 7 wherein the pH-dependent polymer is selected from the group consisting of an ethyl acrylate/methacrylic acid copolymer wherein the ratio of free carboxyl groups to esters is about 1 1, a methyl methacrylate/methacrylic acid copolymer wherein the ratio of free carboxyl groups to esters is from about 1 1 to about 1 2, a methacrylic acid/methyl acrylate/methyl methacrylate copolymer wherein the ratio of the monomers is about 1 5 2 to 3 7 3, and mixtures thereof, -48- ACY-33343 17 6 98 the plasticizer is selected from the group consisting of triethyl citrate and a poly(ethylene glycol) having an average molecular weight of about 1,000 to 10,000, and the stilbene compound is selected from the group consisting of Blancophor BBH, Calcofluor White M2R, Phorwite AR, and mixtures thereof 9 A process as claimed m any one of Claims 1 to 8 wherein the pH-dependent polymer is a methyl methacrylate/methacrylic acid copolymer and is partially solubilized with base 10 A process as claimed m Claim 9 wherein the base is selected from the group consisting of ammonium hydroxide, an alkali metal hydroxide, and an alkaline earth metal hydroxide 11 A process as claimed m any one of Claims 1 to 10 wherein in said drying step the aqueous mixture is spray dried 12 A process as claimed m any one of Claims 1 to 11 wherein the coated pesticidal matrix has a particle size less than about 2 0 |lm 13 A process as claimed m any one of Claims 1 to 12 wherein the coated pesticidal matrix has a particle size of about 2 |lm to 10 }lm 14 A process as claimed in any one of Claims 1 to 13 wherein the coated pesticidal matrix comprises about 1 to 50% by weight of the pesticidal agent, about 5 to 50% by weight of the pH-dependent polymer, 0 to about 25% by -49- ACY-33343 17 6 98 weight of the plasticizer, 0 to about 30% by weight of the ultraviolet protector, 0 to about 75% by weight of the activity enhancer, and 0 to about 15% by weight of the glidant 15 A coated pesticidal matrix which comprises about 1 to 50% by weight of a pesticidal agent, about 5 to 50% by weight of a pH-dependent polymer wherein a substantial number of the free carboxylic acid groups in said polymer have not been converted to their salt form, 0 to about 25% by weight of a plasticizer, 0 to about 30% by weight of an ultraviolet protector, 0 to about 75% by weight of an activity enhancer, and 0 to about 15% by weight of a glidant 16 A coated pesticidal matrix as claimed in Claim 15 which comprises about 5 to 3 5% by weight of the pesticidal agent, about 10 to 45% by weight of the pH-dependent polymer, 0 to about 2 5% by weight of the plasticizer, 0 to about 20% by weight of the ultraviolet protector, 0 to about 45% by weight of the activity enhancer, and 0 to about 10% by weight of the glidant 17 A coated pesticidal matrix as claimed m Claim 15 wherein the pH-dependent polymer is selected from the group consisting of an ethyl acrylate/methacrylic acid copolymer, a methyl methacrylate/methacrylic acid copolymer, a methacrylic acid/methyl acrylate/methyl methacrylate copolymer, and mixtures thereof, the plasticizer is selected from the group consisting of a poly(ethylene glycol), a poly(propylene glycol), a citric acid ester, diethyl phthalate, dibutyl phthalate, castor oil, triacetm, and mixtures thereof, the ultraviolet -50- ACY-33343 17 6 98 protector is selected from the group consisting of carbon black, a benzophenone, a dye, titanium dioxide, and mixtures thereof, the activity enhancer is a stilbene compound, and the glidant is selected from the group consisting of talc, magnesium stearate, calcium stearate, calcium sulfate, and mixtures thereof 18 A coated pesticidal matrix as claimed in Claim 17 wherein the pH-dependent polymer is selected from the group consisting of an ethyl acrylate/methacrylic acid copolymer wherein the ratio of free carboxyl groups to esters is about 1 1, a methyl methacrylate/methacrylic acid copolymer wherein the ratio of free carboxyl groups to esters is from about 1 1 to about 12, a methacrylic acid/methyl acrylate/methyl methacrylate copolymer wherein the ratio of monomers is about 1 5 2 to 3 7 3, and mixtures thereof; the plasticizer is selected from the group consisting of triethyl citrate and a poly(ethylene glycol) having an average molecular weight of about 1,000 to 10,000, and the stilbene compound is selected from the group consisting of Blancophor BBH, Calcofluor White M2R, Phorwite AR, and mixtures thereof 19 A coated pesticidal matrix as claimed m any one of Claims 15 to 18 wherein the pesticidal agent is a chemical insecticide or a biological insecticide 20 A coated pesticidal matrix as claimed m any one of Claims 15 to 18 wherein the pesticidal agent is a chemical insecticide selected from the group consisting of chlorfenapyr, hydramethylnon, imidaclopnd, 1-<6-chloro-3-pyridyl)-2-(nitromethylene)imidazolidine, fipronil, and

1- -51- ACY-33343 17.6 98 [1-(p-chlorophenyl)-

2-fluoro-4-(4-fluoro-

3-phenoxyphenyl)-2-butenyl]cyclopropane, (R,S)-(Z)-, and mixtures thereof 21. A coated pesticidal matrix as claimed in any one of Claims 15 to 18 wherein the pesticidal agent is a biological insecticide selected from the group consisting of V8vEGTDEL, V8vEGTDEL-AaIT, Heliothis zea NPV, Lymantria dispar NPV, AcMNPV E2, AcMNPV LI, ACMNPV V8, AcMNPV Pxl, and Bacillus thurmgiensis, and mixtures thereof 22 A coated pesticidal matrix as claimed in any one of Claims 15 to 21 having a particle size of less than about 2 0 |im 23 A coated pesticidal matnxas claimed in any one of Claims 15 to 21 having a particle size of about 2 |tm to 10 |im 24 A wettable powder pesticidal composition which comprises about 0 5 to 40% by weight of a dispersing agent, about 1 to 10% by weight of a flow enhancing agent, about 10 to 70% by weight of a bulking agent, 0 to about 25% by weight of a wetting agent, 0 to about 35% by weight of a pH-modifying agent, and about 5 to 75% by weight of a coated pesticidal matrix as defined in any one of Claims 15 to 21 25 A composition as claimed in Claim 24 which comprises about 2 to 15% by weight of tne dispeising agent, about 1 to 10% by weight of the flow enhancing agent, about 10 to 60% by weight of the bulking agent, -52- ACY-33343 17 6 98 0 to about 15% by weight of the wetting agent, 0 to about 20% by weight of the pH-modifying agent, and about 5 to 75% by weight of the coated pesticidal matrix 26 A composition as claimed in Claim 24 or Claim 25 wherein the pesticidal agent m the coated pesticidal matrix is a biological agent 27 A composition as claimed m Claim 2 6 which comprises about 2 to 10% by weight of tne dispersing agent, about 1 to 10% by weight of the flow enhancing agent, about 20 to 50% by weight of the bulking agent, about 2 to 20% by weight of the pH-modifying agent, and about 15 to 60% by weight of the coated pesticidal matrix 28 A composition as claimed m any one of Claims 24 to 27 wherein the pH-modifying agent is an organic acid 29 A composition as claimed in Claim 28 wherein the organic acid is citric acid 30 A composition as claimed in Claim 28 wherein the organic acid has a mean particle size greater than about 50 (im 31 A composition as claimed m Claim 30 wherein the organic acid has a mean particle size greater than about 100 Jim -53- 7 y? - 0»j 0 ^ / I ; t j/ fa 32 A coated pesticidal matrix produced by the process defined m any one of Claims 1 to 14 33 A method for improving the residual control of a pest which comprises applying to the locus of the pest a pesticidally effective amount of a coated pesticidal matrix defined m any one of claims 15 to 32 34 A coated pesticidal matrix obtainable by the process defined m any one of Claims 1 to 14 3 5 A process for the preparation of a coated pesticidal matrix as defined m claim 1 substantially as herein described with reference to any example thereof 3 6 A coated pesticidal matrix as defined m claim 15 substantially as herein described with reference to any example thereof 37 A wettable powder pesticidal composition as defined m claim 24 substantially as herein described with reference to any example thereof 3 8 A method for improving the residual control of a pest as claimed m claim 33 substantially as herein described with reference to any example thereof By the authorised agents rcvOCC\"V AJ PARK & SON ^ i </div>