CA1044134A - Microcapsule insecticide composition - Google Patents
Microcapsule insecticide compositionInfo
- Publication number
- CA1044134A CA1044134A CA248,015A CA248015A CA1044134A CA 1044134 A CA1044134 A CA 1044134A CA 248015 A CA248015 A CA 248015A CA 1044134 A CA1044134 A CA 1044134A
- Authority
- CA
- Canada
- Prior art keywords
- shell
- composition
- composition according
- pyrethroid
- liquid fill
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
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
- B01J13/20—After-treatment of capsule walls, e.g. hardening
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/30—Low-molecular-weight compounds
- C08G18/32—Polyhydroxy compounds; Polyamines; Hydroxyamines
- C08G18/3225—Polyamines
Abstract
ABSTRACT
A microcapsule insecticide composition comprising microcapsules each having a polyurea shell wall including as an integral part of said shell a photostable ultraviolet light absorbent compound with a log molar extinction co-efficient of from about 2 to about 5 with respect to radi-ation having wave lengths in the range of from about 270 to 350 nanometers and a liquid fill capable of slowly permea-ting the shell and comprising a pyrethroid and a biological synergist therefor.
A microcapsule insecticide composition comprising microcapsules each having a polyurea shell wall including as an integral part of said shell a photostable ultraviolet light absorbent compound with a log molar extinction co-efficient of from about 2 to about 5 with respect to radi-ation having wave lengths in the range of from about 270 to 350 nanometers and a liquid fill capable of slowly permea-ting the shell and comprising a pyrethroid and a biological synergist therefor.
Description
- ~.N. 912,242 MICROCAPSULE INSECTICIDE COMPOSITION
The present invention relates to microcapsule insecticide compositlons which are stabili~ed against environmental degradation.
Pyrethroids, including both the naturally occurring compounds and their synthetically prepared analogs 7 are a well known class o~ contact insecticides.
They have broad spectrum activity~ that is, they are effective in controlling a variety Or pests such as house-.: . , , flies, mosquitoes~ cockroaches, etc. They are not harmful ~;
to plants, food, animals and humans and are consequently environmentally saf`e (leaving no harmful residues).
Despite these highly favorable characteristics, pyrethroids have had only limited usefulness because of their relatively short lived insecticidal activity. This is due to their decomposition into non-active, non-insecticidal products in the presence of oxygen and ultra-violet light. The speed o~ this decomposition (or environ-mental degradation) is dependent upon the environment in which the pyrethroids are placed but typically takes place in from several minutes to several hours. Thus the useful- ~;
ness ~f pyrethroids as insecticides has been severely limited by their instability.
Encapsulation of a variety of ac~ive liquid sub-stances (including dyes~ inks, chemical reagents, pharma-ceuticals, flavoring materials, pesticides, herbicides and peroxides) has been suggested to preserve them until i released by crushing, melting~ dissolving or otherwise removing the capsule wall or until release by dlffusion is ~ .
' :, -,: , ef~ected (see for example U.S. Patent 3~577,515). Thls en-capsulation per se is not of great help in the delivery of pyrethroids, since they degrade almost as readlly inside ' the capsules as they do unencapsulated.
Various speclfic attempts have been made to stabilize pyrethroids against environmental degradation.
Thus, antioxidants, biological synergists and photostable ultraviolet light absorbent compounds have been added to solutions of the pyrethroids. Various solid carriers have also been used, such as gum arabic, dextrin, gelatin~ un-vulcanized rubbers, inorganic powders, and other polymeric products. These attempts have been at best only very moderately successful in reducing the degradation by atmos-pheric oxy~en and ultraviolet radiation and extending the insecticidal life of pyrethroids. Furthermore, they leave behind unsightly residues which are difficult to remove The pyrethroids are also easily dissolved and washed away by water rinsing (e.g. by rain) thereby preventing their ; timed release. ;
In accordance with the present invention there is provided a microcapsule insecticide composition comprising microcapsules each having a polyurea shell including as an integral part of said shell a photostable ultraviolet light absorbent compound having a log molar extinction coefficient of from about 2 to 5 with respect to radiation having wave lengths in the range of from about 270 to 350 nanometers and a llquid fill capable of slowly permeating the shell and comprising a pyrethroid and a biological synergist there~or.
. :
3~
Preferably the entire microcapsule composition consists essentially of 60-go percent of liquid fill and 40-lO percent o~ shell wall, the liquid fill comprising 5-40 percent of pyrethroid, 25-50 percent of biological synergist and 20-40 percent of a water-lmmiscible organlc solvent and the shell including as an lntegral part thereof 0.5-20 percent of photostable ultraviolet light absorbent compound (all percentages being based on the weight of the entire microcapsule composition).
The pyrethroid remains inside the microcapsules . ,~ . .
while the composltion is packaged and in storage, i.e. in -a closed container due to the partial pressure of the pyrethroid surroundlng the microcapsules. When the product is applied as an insecticide, the pyrethroid releases slowly (the actual speed of release depending upon the ., thickness and porosity of the capsule walls). The pyre-throid is chemically stable during storage and after appli-cation until it permeates the capsule walls. At that time it becomes available as an insecticide until degraded to an inactive product. Since the fill permeates the shell wall slowly, the microcapsule product has a long effective insecticidal life and may be stored for extended periods (e.gO for 6 months and more).
The invention also provides a process for con- ~-trolling insect pests activity by contacting said insects with an ef~ective level of the compositions of the present invention~ Contact may be accomplished directly, for example, by atomi7ation of the composition into the air in the form of a spray so that it contacts the insect ,~ 30 directly or indirectly by applying the composition to , ~ , ' ` ~:
~; ~3~ }
", .,.~ .
, .
., .
~- - - . .- .. . : .
. . ~ - . : : :
.
~14~
surfaces upon which the insects alight or crawl. Alter-natively, compositions of the present invention may be provided in various other forms, for example in sheet materials carrying the microcapsules, (e.g. tapes coated or impregnated with the microcapsules~ that may be placed in areas where the insects may allght or crawl.
Moreover~ animals infested ~ith insectsg for example, dogs and cats infested with fleas and poultry infested with lice, can be treated by contacting the fur or feathers of the animal with the compositions of the present ; invention thereby ending the insect infestation. Other methods of controlling insect activity ~ith formulations of the present invention will be obvious as a result of this disclosure.
The microcapsule insecticide compositions Of the present invention are conveniently prepared by first dispersing a solution comprising the pyrethroid, the biological synergist, a polyisocyanate and a water- ;
immiscible organic solvent in water by means of agitation and then adding a polyfunctional amine to the water phase whlle continuing agitationO The microcapsules are formed by interaction between the isocyanate and amine groups at the surfaces of the drops of the disperse phase. An anti-oxidant and/or a photostable ultraviolet light absorbent compound (sometimes referred to herein as the fill stabilizer) may also be included in the disperse phase -~
solution.
A photostable ultraviolet light absorbent com-~ pound having a log molar extinction coefficient of from .~1 :, .
~ 30 about 2 to 5 ~Jith respect to radiation in the 270 to 350 ~
' .
~4~ ;
'- ~
- ~ . . . . . . .
. .
nanometer wave length range (sometimes referred to herein as the shell stabilizer) is included in the lnitial charge ; or is added subsequently (as will be explained) so that it becomes an integral part of the shell wall.
- 5 The liquid fill may be prepared by simple ad-mixture of the pyrethroid, the organic so~vent, the biolog-ical synergist and optionally the antloxidant and/or the fill stabilizer.
There are a number of possible variatlons in the encapsulation process, although all depend upon the forma-tion of a fine dispersion of the liquid ~ill (containing the polyisocyanate) in water, for example by means of a high shear mixing apparatus (e.g. a blender). A suspending ;
aid (e.g. the partially neutrali~ed salt of polyacrylic acid such as sodium or potassium polyacrylate or sodium or potassium polymethacrylate) is employed to prevent agglom-eration of the droplets of liquid fill When the dispersion has been established, a polyfunctlonal amine (preferably from about 0.5 to 3 amine equivalents per isocyanate equiv-alent, each prlmary or secondary amine ~roup being theoret-ically equivalent to one isocyanate group) is preferably added slowly and an organic polyurea microcapsule shell wall ~orms around each droplet of liquld fillo The shell '! wall is insoluble ln the liquid fill and the w~ter thereby isolating the liquid fill from the external environment.
' It does, however, allow the pyrethroid to permeate it ; slowly thereby maintaining an effective level of insecti~
cide upon the outer surface of the shell wall for extended ~ -periods of time. Typically preparation of the microcapsule compositions is carried out at from about 15C.-50C.
'', ., : . -, . . . .
.
3~
Preferably at least one o~ the shell wall react-ants is more than bifunctional thereby introducing a de-gree o~ crosslinking into the shell wall. However, bl-functional reactants (e.g. toluene diisocyanate and ethylene diamine) may also be used thereby resulting in a shell wall containing essentially no crossllnking.
Generally the greater the degree of crosslinking in the shell wall, the less permeable the shell wall is to the pyrethroid.
The microcapsules obtained comprise a distribu-tion of spherical capsules generally ranging from about 1 to 100 microns, and preferably from about 1 to 30 microns, in diameter. Microcapsules having a narrow distribution of diameters may be obtained by adding the polyfunctional 15 amlne slowly, preferably in the form of' an aqueous solu-. ~ , . .
tion. Larger and smaller capsules may also be obtained, the lar~er capsules being produced by low shear and vice I versa.
;~ The shell stabilizer is an essential park of the final microcapsules composition and is an integral part of the polyurea shell wall. This may be accomplished by a :, . .
variety of chemical or physicochemical methods. For -~
example: ~;
1. Reacting the shell stabilizer with available primary, secondary~ or tertiary amine groups on the shell wall by adding it to the dis-, persion of the microencapsulated insecticide `'1 composition.
The present invention relates to microcapsule insecticide compositlons which are stabili~ed against environmental degradation.
Pyrethroids, including both the naturally occurring compounds and their synthetically prepared analogs 7 are a well known class o~ contact insecticides.
They have broad spectrum activity~ that is, they are effective in controlling a variety Or pests such as house-.: . , , flies, mosquitoes~ cockroaches, etc. They are not harmful ~;
to plants, food, animals and humans and are consequently environmentally saf`e (leaving no harmful residues).
Despite these highly favorable characteristics, pyrethroids have had only limited usefulness because of their relatively short lived insecticidal activity. This is due to their decomposition into non-active, non-insecticidal products in the presence of oxygen and ultra-violet light. The speed o~ this decomposition (or environ-mental degradation) is dependent upon the environment in which the pyrethroids are placed but typically takes place in from several minutes to several hours. Thus the useful- ~;
ness ~f pyrethroids as insecticides has been severely limited by their instability.
Encapsulation of a variety of ac~ive liquid sub-stances (including dyes~ inks, chemical reagents, pharma-ceuticals, flavoring materials, pesticides, herbicides and peroxides) has been suggested to preserve them until i released by crushing, melting~ dissolving or otherwise removing the capsule wall or until release by dlffusion is ~ .
' :, -,: , ef~ected (see for example U.S. Patent 3~577,515). Thls en-capsulation per se is not of great help in the delivery of pyrethroids, since they degrade almost as readlly inside ' the capsules as they do unencapsulated.
Various speclfic attempts have been made to stabilize pyrethroids against environmental degradation.
Thus, antioxidants, biological synergists and photostable ultraviolet light absorbent compounds have been added to solutions of the pyrethroids. Various solid carriers have also been used, such as gum arabic, dextrin, gelatin~ un-vulcanized rubbers, inorganic powders, and other polymeric products. These attempts have been at best only very moderately successful in reducing the degradation by atmos-pheric oxy~en and ultraviolet radiation and extending the insecticidal life of pyrethroids. Furthermore, they leave behind unsightly residues which are difficult to remove The pyrethroids are also easily dissolved and washed away by water rinsing (e.g. by rain) thereby preventing their ; timed release. ;
In accordance with the present invention there is provided a microcapsule insecticide composition comprising microcapsules each having a polyurea shell including as an integral part of said shell a photostable ultraviolet light absorbent compound having a log molar extinction coefficient of from about 2 to 5 with respect to radiation having wave lengths in the range of from about 270 to 350 nanometers and a llquid fill capable of slowly permeating the shell and comprising a pyrethroid and a biological synergist there~or.
. :
3~
Preferably the entire microcapsule composition consists essentially of 60-go percent of liquid fill and 40-lO percent o~ shell wall, the liquid fill comprising 5-40 percent of pyrethroid, 25-50 percent of biological synergist and 20-40 percent of a water-lmmiscible organlc solvent and the shell including as an lntegral part thereof 0.5-20 percent of photostable ultraviolet light absorbent compound (all percentages being based on the weight of the entire microcapsule composition).
The pyrethroid remains inside the microcapsules . ,~ . .
while the composltion is packaged and in storage, i.e. in -a closed container due to the partial pressure of the pyrethroid surroundlng the microcapsules. When the product is applied as an insecticide, the pyrethroid releases slowly (the actual speed of release depending upon the ., thickness and porosity of the capsule walls). The pyre-throid is chemically stable during storage and after appli-cation until it permeates the capsule walls. At that time it becomes available as an insecticide until degraded to an inactive product. Since the fill permeates the shell wall slowly, the microcapsule product has a long effective insecticidal life and may be stored for extended periods (e.gO for 6 months and more).
The invention also provides a process for con- ~-trolling insect pests activity by contacting said insects with an ef~ective level of the compositions of the present invention~ Contact may be accomplished directly, for example, by atomi7ation of the composition into the air in the form of a spray so that it contacts the insect ,~ 30 directly or indirectly by applying the composition to , ~ , ' ` ~:
~; ~3~ }
", .,.~ .
, .
., .
~- - - . .- .. . : .
. . ~ - . : : :
.
~14~
surfaces upon which the insects alight or crawl. Alter-natively, compositions of the present invention may be provided in various other forms, for example in sheet materials carrying the microcapsules, (e.g. tapes coated or impregnated with the microcapsules~ that may be placed in areas where the insects may allght or crawl.
Moreover~ animals infested ~ith insectsg for example, dogs and cats infested with fleas and poultry infested with lice, can be treated by contacting the fur or feathers of the animal with the compositions of the present ; invention thereby ending the insect infestation. Other methods of controlling insect activity ~ith formulations of the present invention will be obvious as a result of this disclosure.
The microcapsule insecticide compositions Of the present invention are conveniently prepared by first dispersing a solution comprising the pyrethroid, the biological synergist, a polyisocyanate and a water- ;
immiscible organic solvent in water by means of agitation and then adding a polyfunctional amine to the water phase whlle continuing agitationO The microcapsules are formed by interaction between the isocyanate and amine groups at the surfaces of the drops of the disperse phase. An anti-oxidant and/or a photostable ultraviolet light absorbent compound (sometimes referred to herein as the fill stabilizer) may also be included in the disperse phase -~
solution.
A photostable ultraviolet light absorbent com-~ pound having a log molar extinction coefficient of from .~1 :, .
~ 30 about 2 to 5 ~Jith respect to radiation in the 270 to 350 ~
' .
~4~ ;
'- ~
- ~ . . . . . . .
. .
nanometer wave length range (sometimes referred to herein as the shell stabilizer) is included in the lnitial charge ; or is added subsequently (as will be explained) so that it becomes an integral part of the shell wall.
- 5 The liquid fill may be prepared by simple ad-mixture of the pyrethroid, the organic so~vent, the biolog-ical synergist and optionally the antloxidant and/or the fill stabilizer.
There are a number of possible variatlons in the encapsulation process, although all depend upon the forma-tion of a fine dispersion of the liquid ~ill (containing the polyisocyanate) in water, for example by means of a high shear mixing apparatus (e.g. a blender). A suspending ;
aid (e.g. the partially neutrali~ed salt of polyacrylic acid such as sodium or potassium polyacrylate or sodium or potassium polymethacrylate) is employed to prevent agglom-eration of the droplets of liquid fill When the dispersion has been established, a polyfunctlonal amine (preferably from about 0.5 to 3 amine equivalents per isocyanate equiv-alent, each prlmary or secondary amine ~roup being theoret-ically equivalent to one isocyanate group) is preferably added slowly and an organic polyurea microcapsule shell wall ~orms around each droplet of liquld fillo The shell '! wall is insoluble ln the liquid fill and the w~ter thereby isolating the liquid fill from the external environment.
' It does, however, allow the pyrethroid to permeate it ; slowly thereby maintaining an effective level of insecti~
cide upon the outer surface of the shell wall for extended ~ -periods of time. Typically preparation of the microcapsule compositions is carried out at from about 15C.-50C.
'', ., : . -, . . . .
.
3~
Preferably at least one o~ the shell wall react-ants is more than bifunctional thereby introducing a de-gree o~ crosslinking into the shell wall. However, bl-functional reactants (e.g. toluene diisocyanate and ethylene diamine) may also be used thereby resulting in a shell wall containing essentially no crossllnking.
Generally the greater the degree of crosslinking in the shell wall, the less permeable the shell wall is to the pyrethroid.
The microcapsules obtained comprise a distribu-tion of spherical capsules generally ranging from about 1 to 100 microns, and preferably from about 1 to 30 microns, in diameter. Microcapsules having a narrow distribution of diameters may be obtained by adding the polyfunctional 15 amlne slowly, preferably in the form of' an aqueous solu-. ~ , . .
tion. Larger and smaller capsules may also be obtained, the lar~er capsules being produced by low shear and vice I versa.
;~ The shell stabilizer is an essential park of the final microcapsules composition and is an integral part of the polyurea shell wall. This may be accomplished by a :, . .
variety of chemical or physicochemical methods. For -~
example: ~;
1. Reacting the shell stabilizer with available primary, secondary~ or tertiary amine groups on the shell wall by adding it to the dis-, persion of the microencapsulated insecticide `'1 composition.
2. Prereacting the polyfunctional amine with ~l 30 the shell stabilizer. The resulting modified '1 .
-6- ~
' -,, . " ,.,. ~ ,. . ~ ,, . :
poly~unctional amlne is added to the dis perslon of liquid fill containing khe poly-; isocyanate and a polyurea microcapsule shell wall forms around each droplet of liquid fill.
Suitable shell stabilizers for processes 1 and 2 contain acidic reactive groups. The amount of amlne functions added in each case is preferably from about 1.1 to 3 amine equivalents per isocyanate equivalent so that there will be excess amine available for reacti~n with the shell stabilizer (whlch takes about 5 minutes).
-6- ~
' -,, . " ,.,. ~ ,. . ~ ,, . :
poly~unctional amlne is added to the dis perslon of liquid fill containing khe poly-; isocyanate and a polyurea microcapsule shell wall forms around each droplet of liquid fill.
Suitable shell stabilizers for processes 1 and 2 contain acidic reactive groups. The amount of amlne functions added in each case is preferably from about 1.1 to 3 amine equivalents per isocyanate equivalent so that there will be excess amine available for reacti~n with the shell stabilizer (whlch takes about 5 minutes).
3. Reacting the polyisocyanate with the shell stabillzer before the polylsocyanate is included in the liquid fill which is dis-~ 15 persed and reacted with a polyfunctional -~ amine to form ~he polyurea shell wall.
Suitable shell stabilizer for process 3 contain active hydrogen. The amount of amine functions added in this case is preferably from about 0.5 to 3 amlne equiva-lents per isocyanate equivalent.
: .
Suitable shell stabilizer for process 3 contain active hydrogen. The amount of amine functions added in this case is preferably from about 0.5 to 3 amlne equiva-lents per isocyanate equivalent.
: .
4. The shell photostabilizer may also be ;--physicochemically included in the shell ~
: : -wall by reactlng an amine with a shell stabilizer compound and the resultant modifled amine coated onto a microencap-sulated insecticide composition. ' :, .
~ 5. Another method of physicochemlcal lnclusion .~,'! involves coating a microencapsulated insecti-cide composition with polymeric materlals and inorganic sols.
~7~
;.
:
During microencapsulation and incorpoaration of the shell s-tabilizer and the pH of the dispersion of the reaction mixture is maintained a-t from about 7-8 to ; enable the suspending aid to prevent agglomera-tion of the droplets and the microcapsules.
Suitable pyrethroids for use in the liquid fill include both the naturally occurring pyrethrum es-ters derived from the dried Elower heads of Chrysanthemurrl cinnerariaefolium and Chrysanthemum coccineum and the synthetically prepared esters of chrysanthemic ac:id .
Na-turally occurring pyre-thrum es-ters comprise the group ,, ~ .
including pyrethrin I, pyrethrin II, cinerin I, cinerin II, and jasmolin II. Synthetically prepared esters com-prise the group including allethrins, barthrin, dimethrin, -resmethrin, and tetramethrin. The pyrethroids used in the liquid fill may comprise any ~f the naturally occur-ring pyrethroids, any of the synthetically prepared ~-pyrethroids, or combinations of two or more of either or ~;~ both types. A solution of a combination of naturally -occurring pyrethroids in deodorized kerosene which is commercially available under the trade designation "Pre~
mium Pyrocide 175" *from McLaughlin Gormley King Co. of l Minneapolis, Minnesota is suitable for use in the present '~i invention.
. ,,1 . .
The synthetic pyrethroids in pure form are cryst-~; alline materials which are capable of being dissolved in water irnmiscible organic solvents. Thus the micro-capsule compositions of the invention may include up to - 40 percent by weight or even more of the pyrethroid.
Ordinarily the compositions contain at least about 5 percent.
' *TRA~E MARK - 8 -;' '- ~:
"
39~
of pyrethroids since lesser amounts thereof result in products of unnecessarily low insecticidal activity.
Preferably the microcapsule compositions contain from about 5 to 15 percent (by weight) of pyrethroids.
Suitable biological synergists for inclusions in the liquid fill genera]ly have little or no insecticidal activity by themselves but significantly increase the insecticidal activity of the pyrethroids when combined therewith. A variety of synergis-ts are useful in com-positions of the present invention. Representative examples of these synergists are given on pages 196-197 of Pyrethrum the Natural lnsecticide,edited~by John E.
~ .
Casida, Academic Press, New York and London,1973. Among -the preferred biological synergists are the piperonyl alkyl ethers such as 3,4-methylenedioxy-6-propylbenzyl ~ ;~
`I butyldiethylene glycol~ether (also known as piperonyl butoxide), commercially available under the -trade desig-1 nation "Butacide"* from Niagra Chemical Division of FMC
Corp~ and N-(2-ethylhexyl)-bicyc~o 2.2.1 -5-heptene-2,3 dicarboximide commercially available under the -trade designation "MGK-264" :from the McLaughlin Gormley King I Co. of Minneapolis, Minnesota. -; The shell stabilizers that are includes as an integral part of the shell wall have log molar extinc-tion coefficients of from about 2 to 5 with respect to radlation having wave lengths of from about 270 to 350 nanometers but only minimal absorption in the visible portion of the spectrum. The shell stabilizers are ~,1 chemically and/or physicochemically bonded or held i~ , -,~ in or on the shell wall thus forming an integral part ` thereof. The particular *TRADE MARK
_ g _ :
~' ,, ,: - -: . - - . . :
, . . .
:-: ~ : , , type of shell st~bilizlng compound used will depend upon the manner in which it is incorporated as will become clear. Thus when the shell stabilizer is chemically bonded in or on the shell wall it will include one or more photo-stable ultraviolet light absorbent moieties (X'~ and one or more groups reaccive with isocyanate or amlne (Q).
Thus R' may include, for example, benzophenone, substituted benzophenone, benzotriazole, phenyl salycilate, etc.
groups. When Q is reactive toward isocyanate it will con-tain active hydrogen (e.gO 01l0present in primary, secondary, ,.
or tertiary alcohols, -NH2, -CN~INH2, ~CNH2, -S02NH2, -CH=N0Hs etc.) When Q is reactive towards amine it will ~ contaln acidic groups hav:ing a dissociation constant of at - least about 1 x 10 6 and includes among others, carboxylicand sulfonic acid groupsO A preferred class of shell stabilizers comprises substituted benzophenone sulfonic acids, particularly 2-hydroxy-4-methoxybenzophenone~5-sul~onic acid.
Compounds suitable as the shell stabilizers that ; 20 are physicochemically hel~ on the shell wall include inter-polymers of vinyl compounds and unsaturated dicarboxylic acids reacted with hydroxybenzophenones (such as those described in U.S. Patent No. 3,393,990) and inorganic sols.
e g. sols of Fe23, Cr23~ Ti2' A123' -The shell stabilizer may comprise from about 0.5 -to 20 percent by Neight of the microcapsule composition Preferably it comprises from about 8 to 10 percent by weight of the microcapsule composition Suitable water immiscible organic solvents for use in the liquid fill include a wide variety of materlals ~-' 10 ,~
', ~, :~, ~., , . :- . - - ~ . .
: . .: ,, :, . ,, ~, . . , ~
.
conventionally employed in insecticidal formulations.
Preferably the sol~ent is inert, that is, it is lncapable of undergoing chemical reaction with the pyrethroid or any other components of the fill under ambient storage or end use conditions Also, the solvent is, preferably, one that will not be harm~ul to the environment in which it is used.
Representative e~a~ples of organic solvents useful in the llquid fill include liquid aliphatic hydro-carbons such as pentane, nonane, and decane and their ; analogs and liquid aromatic hydrocarbons such as benzene, toluene, xylene, etc. Commercially advantageous liquid - hydrocarbon products useful in the liqul~ fill include oils produced from the distillation of coal and the distillation of various types and trades of petroleum stocks. Representative examples of these oils include kerosene, liquid paraffin, paraffin oil, llght mineral oil and white mineral oil. Still other solvents useful in the liquid fill include aromatic and aliphatic esters, higher aldehydes1 and higher ketones. An especially pre-ferred organic solvent for use in the present invention is deodori~ed kerosene~
Suitable polyisocyanates ror use in the present in~ention have an isocyanate equivalent weight in the range of from about 70 to l~oo, and may be represented by ~j the general formula R(NCO~n wherein R is alkyl, cyclo-alkyl~ aryl, aralkyl or alkaryl and n may be as high as 10 but is preferably 2 to 3~ A preferred sub-class are those containing 2 isocyanate groups. The polyisocyanates are substantially insoluble in water but are readily :;, '. -11 -~' ,:
- - ,; .
; . :
3~
soluble in ttle solven-t used in the liquid fill. Repre-sentative examples of polyisocyanates useful in the prese~ invention include hexamethylene diisocyanate, 1, 4-cyclo-hexane diisocyante, methylene-bis~4,4'-cyclohexy-lisocyanate, isopropylidene-bis-4,4'-cyclohexylisocyanats, dimer diisocyanate (an isocyanate of the formul OCN-D~NCO
wherein D is a C36 alipha-tic moie-ty and is commercially available as "DDI"* from General Mills), methane diisocyan-ate, and isophorone diisocyanate. Flepresentative examples of still other useful polyisocyanates include m-phenylene diisocyanate, mi~utes of toluene-2,4-diisocyanate and toluene-2,6-diisocyanate, diphenyl-3,3~imethyl-4 9 4'-diisocyanate~ diphenyl-3,3'-dimethoxy-4,4'diisocyanate, diphenylmethane-4~4'dilsocyanate, diphenylmethane-4,4'- -dime-thyl-3,3'-diisocyanate, 1,5-napthalene diisocyanate.
l`he so-called polymeric polyisocyanates can also be used, such as those obtained by phosgenation of polyamines, -prepared by condensing formaldehyde with aromatic amines. ~ -Particularly useful polymeric polyisocyanates are the polymethylene polyphenyl polyisocyana-tes having an average of from about 2 to 2.8 idocyanate groups per molecule such as those sold commercially under the trade desig-nations "Mondur"* MR and MRS, (available from Mobay CO.). Lists of commercially available polyisocyanates are found in Kirk and Othmer, Encyclopedia of Chemical ....
;1 Tech~ , Vol. 12, 2nd Ed~.l, pp. 46-47, Interscience ~I Publishers ~1967), and Appendix A of Saunders and Frisch Polyurekhanes: Chemistry and Technology, Part I, Inter-science Publishers, New York (1962); and the polyisocy-o~
arlRte materials therein described can be used in this invention.
*TRADE MARK - 12 - ~ ~
:~ :
:.
.,'~ ' ;~
'' ': """ ~"' ' ' ' :, Preferably the polyisocyanate comprises from about 5 to 20 percent by weight of the microcapsule com-position. An especially preferred polyisocyanate is "Mondur" MRS, a poly (methylenephenylene isocyanate) having a molecular weight of about 380 and an average isocyanate equivalent weight of 133 (thus containing ;~ about 2O6 isocyanate groups per molecule). When "Mondur"
MRS is used a~ least a par~ of the water immiscible organic solvent is aromatic. The biological synergists (e.g~ piperonyl butoxlde) are aromatic in nature and thus may serve as the aromatic solvent.
Suitable polyfunctional amines for use in the present invention have at least two primary or secondary amine groups per molecule and have an amine equivalent weight in the range of from about 30 to 400. Addltionally, ; the polyfunctional amines are readily soluble in water and preferably are substantially insoluble in the solvent used in the liquid flll. Generally they are selected as water soluble per se~ However, they may also be selected as the water soluble salts thereof. Useful poly~unctional .. , .:: .
amines include aromatic and aliphatic amines. The aromatic 1 . , amines preferably contain only hydrogen, carbon, nitrogen, and oxygen and the prlmary amine functlons are preferably ;~ bonded directly to 6-membered aromatic carbocycles therein.
The aliphatic amines preferably are hydrocarbon amines ~; containing up to about 36 carbon atoms. Representative ~'j examples of useful polyfunctional amines include ethylene -~ diamlne, diethylene ~riamine, tetraethylene pentamine, ,~ , hexamethylene diamine, pentaethylene hexamine, polyethylene imine, ~,2'-dlaminodiethylether, 1,4-diaminocyclohexane, ', :
..
.' .
.
phenylene diamines (especially m-phenylene diamine), toluene diamine, and melamine. Other amines of the type described are known to the art and are also useful in the present invention. Preferably -the polyEunctional amines comprise from about 1 to 10 percent by weight of`
the microcapsule composition.
Antioxidan-ts may also be included in the liquid fill to minimize the degradative effects of oxygen by inhibiting the formation of hyperoxide groups and their subsequent decomposition into alkoxy and hydroxy radicals in the compositions to be protected. Preferably the antioxidants do not exhibit any substantial chemical reaction with -the isocyanate and primary amine groups of the shell forming compounds during the microencap-sulation process. A variety of antioxidants are useful in compositions of the present invention. Representa-tive examples include alkylated phenols such as 2,6-di-t-butyl cresol, 2,2'-methylene bis (6-t-butyl-4-methyl phenol), 2,2'-thio bis (6-t-bùtyl-4-methyl phenol), pentaerythri-tol tetrakis 3-(3~5-di-tert butyl-4-hydroxyphenyl) propionate, octadecyl 3-(3',5'-di-t- `~
., .
butyl-47-hydroxyphenyl) propionate commercially avail-able under the trade designation of "Irganox'1076"* from Ciba Geigy Corp., etc.; thioesters such as dilauryl thio-dipropionate, dimyristyl thiodipropiona*e; and phosphites such as tris (nonphenyl phosphite). The antioxidants preferably comprise up to 10 percent, and more preferably -~
from about 0.01 to 2 percent, by weight of the micro-` capsule composition.
Suitable fill stabilizers absorb ultraviolet rad-iation in the range of about 270-~50 nanometers and -' ''' ~:' *TRADE MARK - 14 -' ,. ~: .
':; ,,:, ~.
: : . , }~
:
convert lt to a harmless form. They have a hlgh absorption coefficient ln the near ultraviolet portion o~ the spectrum ; (e.g. a log molar extinction coefficient of from about 2 to
: : -wall by reactlng an amine with a shell stabilizer compound and the resultant modifled amine coated onto a microencap-sulated insecticide composition. ' :, .
~ 5. Another method of physicochemlcal lnclusion .~,'! involves coating a microencapsulated insecti-cide composition with polymeric materlals and inorganic sols.
~7~
;.
:
During microencapsulation and incorpoaration of the shell s-tabilizer and the pH of the dispersion of the reaction mixture is maintained a-t from about 7-8 to ; enable the suspending aid to prevent agglomera-tion of the droplets and the microcapsules.
Suitable pyrethroids for use in the liquid fill include both the naturally occurring pyrethrum es-ters derived from the dried Elower heads of Chrysanthemurrl cinnerariaefolium and Chrysanthemum coccineum and the synthetically prepared esters of chrysanthemic ac:id .
Na-turally occurring pyre-thrum es-ters comprise the group ,, ~ .
including pyrethrin I, pyrethrin II, cinerin I, cinerin II, and jasmolin II. Synthetically prepared esters com-prise the group including allethrins, barthrin, dimethrin, -resmethrin, and tetramethrin. The pyrethroids used in the liquid fill may comprise any ~f the naturally occur-ring pyrethroids, any of the synthetically prepared ~-pyrethroids, or combinations of two or more of either or ~;~ both types. A solution of a combination of naturally -occurring pyrethroids in deodorized kerosene which is commercially available under the trade designation "Pre~
mium Pyrocide 175" *from McLaughlin Gormley King Co. of l Minneapolis, Minnesota is suitable for use in the present '~i invention.
. ,,1 . .
The synthetic pyrethroids in pure form are cryst-~; alline materials which are capable of being dissolved in water irnmiscible organic solvents. Thus the micro-capsule compositions of the invention may include up to - 40 percent by weight or even more of the pyrethroid.
Ordinarily the compositions contain at least about 5 percent.
' *TRA~E MARK - 8 -;' '- ~:
"
39~
of pyrethroids since lesser amounts thereof result in products of unnecessarily low insecticidal activity.
Preferably the microcapsule compositions contain from about 5 to 15 percent (by weight) of pyrethroids.
Suitable biological synergists for inclusions in the liquid fill genera]ly have little or no insecticidal activity by themselves but significantly increase the insecticidal activity of the pyrethroids when combined therewith. A variety of synergis-ts are useful in com-positions of the present invention. Representative examples of these synergists are given on pages 196-197 of Pyrethrum the Natural lnsecticide,edited~by John E.
~ .
Casida, Academic Press, New York and London,1973. Among -the preferred biological synergists are the piperonyl alkyl ethers such as 3,4-methylenedioxy-6-propylbenzyl ~ ;~
`I butyldiethylene glycol~ether (also known as piperonyl butoxide), commercially available under the -trade desig-1 nation "Butacide"* from Niagra Chemical Division of FMC
Corp~ and N-(2-ethylhexyl)-bicyc~o 2.2.1 -5-heptene-2,3 dicarboximide commercially available under the -trade designation "MGK-264" :from the McLaughlin Gormley King I Co. of Minneapolis, Minnesota. -; The shell stabilizers that are includes as an integral part of the shell wall have log molar extinc-tion coefficients of from about 2 to 5 with respect to radlation having wave lengths of from about 270 to 350 nanometers but only minimal absorption in the visible portion of the spectrum. The shell stabilizers are ~,1 chemically and/or physicochemically bonded or held i~ , -,~ in or on the shell wall thus forming an integral part ` thereof. The particular *TRADE MARK
_ g _ :
~' ,, ,: - -: . - - . . :
, . . .
:-: ~ : , , type of shell st~bilizlng compound used will depend upon the manner in which it is incorporated as will become clear. Thus when the shell stabilizer is chemically bonded in or on the shell wall it will include one or more photo-stable ultraviolet light absorbent moieties (X'~ and one or more groups reaccive with isocyanate or amlne (Q).
Thus R' may include, for example, benzophenone, substituted benzophenone, benzotriazole, phenyl salycilate, etc.
groups. When Q is reactive toward isocyanate it will con-tain active hydrogen (e.gO 01l0present in primary, secondary, ,.
or tertiary alcohols, -NH2, -CN~INH2, ~CNH2, -S02NH2, -CH=N0Hs etc.) When Q is reactive towards amine it will ~ contaln acidic groups hav:ing a dissociation constant of at - least about 1 x 10 6 and includes among others, carboxylicand sulfonic acid groupsO A preferred class of shell stabilizers comprises substituted benzophenone sulfonic acids, particularly 2-hydroxy-4-methoxybenzophenone~5-sul~onic acid.
Compounds suitable as the shell stabilizers that ; 20 are physicochemically hel~ on the shell wall include inter-polymers of vinyl compounds and unsaturated dicarboxylic acids reacted with hydroxybenzophenones (such as those described in U.S. Patent No. 3,393,990) and inorganic sols.
e g. sols of Fe23, Cr23~ Ti2' A123' -The shell stabilizer may comprise from about 0.5 -to 20 percent by Neight of the microcapsule composition Preferably it comprises from about 8 to 10 percent by weight of the microcapsule composition Suitable water immiscible organic solvents for use in the liquid fill include a wide variety of materlals ~-' 10 ,~
', ~, :~, ~., , . :- . - - ~ . .
: . .: ,, :, . ,, ~, . . , ~
.
conventionally employed in insecticidal formulations.
Preferably the sol~ent is inert, that is, it is lncapable of undergoing chemical reaction with the pyrethroid or any other components of the fill under ambient storage or end use conditions Also, the solvent is, preferably, one that will not be harm~ul to the environment in which it is used.
Representative e~a~ples of organic solvents useful in the llquid fill include liquid aliphatic hydro-carbons such as pentane, nonane, and decane and their ; analogs and liquid aromatic hydrocarbons such as benzene, toluene, xylene, etc. Commercially advantageous liquid - hydrocarbon products useful in the liqul~ fill include oils produced from the distillation of coal and the distillation of various types and trades of petroleum stocks. Representative examples of these oils include kerosene, liquid paraffin, paraffin oil, llght mineral oil and white mineral oil. Still other solvents useful in the liquid fill include aromatic and aliphatic esters, higher aldehydes1 and higher ketones. An especially pre-ferred organic solvent for use in the present invention is deodori~ed kerosene~
Suitable polyisocyanates ror use in the present in~ention have an isocyanate equivalent weight in the range of from about 70 to l~oo, and may be represented by ~j the general formula R(NCO~n wherein R is alkyl, cyclo-alkyl~ aryl, aralkyl or alkaryl and n may be as high as 10 but is preferably 2 to 3~ A preferred sub-class are those containing 2 isocyanate groups. The polyisocyanates are substantially insoluble in water but are readily :;, '. -11 -~' ,:
- - ,; .
; . :
3~
soluble in ttle solven-t used in the liquid fill. Repre-sentative examples of polyisocyanates useful in the prese~ invention include hexamethylene diisocyanate, 1, 4-cyclo-hexane diisocyante, methylene-bis~4,4'-cyclohexy-lisocyanate, isopropylidene-bis-4,4'-cyclohexylisocyanats, dimer diisocyanate (an isocyanate of the formul OCN-D~NCO
wherein D is a C36 alipha-tic moie-ty and is commercially available as "DDI"* from General Mills), methane diisocyan-ate, and isophorone diisocyanate. Flepresentative examples of still other useful polyisocyanates include m-phenylene diisocyanate, mi~utes of toluene-2,4-diisocyanate and toluene-2,6-diisocyanate, diphenyl-3,3~imethyl-4 9 4'-diisocyanate~ diphenyl-3,3'-dimethoxy-4,4'diisocyanate, diphenylmethane-4~4'dilsocyanate, diphenylmethane-4,4'- -dime-thyl-3,3'-diisocyanate, 1,5-napthalene diisocyanate.
l`he so-called polymeric polyisocyanates can also be used, such as those obtained by phosgenation of polyamines, -prepared by condensing formaldehyde with aromatic amines. ~ -Particularly useful polymeric polyisocyanates are the polymethylene polyphenyl polyisocyana-tes having an average of from about 2 to 2.8 idocyanate groups per molecule such as those sold commercially under the trade desig-nations "Mondur"* MR and MRS, (available from Mobay CO.). Lists of commercially available polyisocyanates are found in Kirk and Othmer, Encyclopedia of Chemical ....
;1 Tech~ , Vol. 12, 2nd Ed~.l, pp. 46-47, Interscience ~I Publishers ~1967), and Appendix A of Saunders and Frisch Polyurekhanes: Chemistry and Technology, Part I, Inter-science Publishers, New York (1962); and the polyisocy-o~
arlRte materials therein described can be used in this invention.
*TRADE MARK - 12 - ~ ~
:~ :
:.
.,'~ ' ;~
'' ': """ ~"' ' ' ' :, Preferably the polyisocyanate comprises from about 5 to 20 percent by weight of the microcapsule com-position. An especially preferred polyisocyanate is "Mondur" MRS, a poly (methylenephenylene isocyanate) having a molecular weight of about 380 and an average isocyanate equivalent weight of 133 (thus containing ;~ about 2O6 isocyanate groups per molecule). When "Mondur"
MRS is used a~ least a par~ of the water immiscible organic solvent is aromatic. The biological synergists (e.g~ piperonyl butoxlde) are aromatic in nature and thus may serve as the aromatic solvent.
Suitable polyfunctional amines for use in the present invention have at least two primary or secondary amine groups per molecule and have an amine equivalent weight in the range of from about 30 to 400. Addltionally, ; the polyfunctional amines are readily soluble in water and preferably are substantially insoluble in the solvent used in the liquid flll. Generally they are selected as water soluble per se~ However, they may also be selected as the water soluble salts thereof. Useful poly~unctional .. , .:: .
amines include aromatic and aliphatic amines. The aromatic 1 . , amines preferably contain only hydrogen, carbon, nitrogen, and oxygen and the prlmary amine functlons are preferably ;~ bonded directly to 6-membered aromatic carbocycles therein.
The aliphatic amines preferably are hydrocarbon amines ~; containing up to about 36 carbon atoms. Representative ~'j examples of useful polyfunctional amines include ethylene -~ diamlne, diethylene ~riamine, tetraethylene pentamine, ,~ , hexamethylene diamine, pentaethylene hexamine, polyethylene imine, ~,2'-dlaminodiethylether, 1,4-diaminocyclohexane, ', :
..
.' .
.
phenylene diamines (especially m-phenylene diamine), toluene diamine, and melamine. Other amines of the type described are known to the art and are also useful in the present invention. Preferably -the polyEunctional amines comprise from about 1 to 10 percent by weight of`
the microcapsule composition.
Antioxidan-ts may also be included in the liquid fill to minimize the degradative effects of oxygen by inhibiting the formation of hyperoxide groups and their subsequent decomposition into alkoxy and hydroxy radicals in the compositions to be protected. Preferably the antioxidants do not exhibit any substantial chemical reaction with -the isocyanate and primary amine groups of the shell forming compounds during the microencap-sulation process. A variety of antioxidants are useful in compositions of the present invention. Representa-tive examples include alkylated phenols such as 2,6-di-t-butyl cresol, 2,2'-methylene bis (6-t-butyl-4-methyl phenol), 2,2'-thio bis (6-t-bùtyl-4-methyl phenol), pentaerythri-tol tetrakis 3-(3~5-di-tert butyl-4-hydroxyphenyl) propionate, octadecyl 3-(3',5'-di-t- `~
., .
butyl-47-hydroxyphenyl) propionate commercially avail-able under the trade designation of "Irganox'1076"* from Ciba Geigy Corp., etc.; thioesters such as dilauryl thio-dipropionate, dimyristyl thiodipropiona*e; and phosphites such as tris (nonphenyl phosphite). The antioxidants preferably comprise up to 10 percent, and more preferably -~
from about 0.01 to 2 percent, by weight of the micro-` capsule composition.
Suitable fill stabilizers absorb ultraviolet rad-iation in the range of about 270-~50 nanometers and -' ''' ~:' *TRADE MARK - 14 -' ,. ~: .
':; ,,:, ~.
: : . , }~
:
convert lt to a harmless form. They have a hlgh absorption coefficient ln the near ultraviolet portion o~ the spectrum ; (e.g. a log molar extinction coefficient of from about 2 to
5) but only minimal absorption in the vislble portion o~
; 5 the spectrum. Preferably they do not exhibit any substan~
tial chemical reaction with the isocyanate groups and primary aMine groups of the shell forming compounds during ` the microencapsulation process. Among the compounds which can be used as fill stabilizers are substituted benzo-phenones such as 2,4-dihydroxy benzophenone~ 2-hydroxy l~_ methoxy benzophenone, 2-hydroxy-4-octyloxy benzophenone, etc.; ~he benzotriazoles su¢h as 2-(2-hydroxy-5'-methyl-phenyl) benzotriazole, 2-(3',5'-diallyl-2 7 -hydroxylphenyl) benzotriazole, etc.; substituted acrylates such as ethyl 2-cyano-3,3-diphenyl acrylate, 2~ethylhexyl-2-cyano-3,3-diphenyl acetate, etc.; salicylates such as phenyl sali-cylates, 5-butyl phenyl sallcylate, etc.; and nickel organic compounds such as nickel bis (octylphenol) sulfide, ~ etc~ Additional examples of each of these classes of fill `` 20 stabllizers may be found in Kirk-Othmer, Encyclopedia of Chemical Technolo~y, Second Edition~ Volume 21, Inter-science Publishers (1970). The fill stabilizers may com- ~;
prise up to 5 percent, and preferably ~rom about 0~01 to 2 percent, by weight of the microcapsule composition.
The sustained release characteristics and insecticldal lifetime of compositions of the present invention are determined by measuring their biological ~, activity, that is, by determining the percentage of house "~.
- flies ( usca domestlca) that are knocked down a~ter ~arious ~, 30 lengths of exposure to the compositionO As the biological : , :
1,, , ~ ,.... .. .
~ . .
L.a~
; activity of an insectlcide decreases, more exposure time is necessary in order to obtain a given percent knockdown.
Knockdown ls defined to mean a condition of paraiysis and ~i immobilization typically characterized by the insect lying on its back with, at most, intermittent bursts of uncontrolled kicking and spinning motion or sporadlc - crippled and unsuccessful attempts at crawling with llttle or no takeoff or fllghto : Biological activity is determined by means o~
a bioassay test performed both initially (e.g. before the insecticide composition is exposed to simulated outdoor condltions) and after the insecticide composition is exposed to simulated outdoor conditions. In performing the bioassay test, specimens of the insecticide composition ~ -15 to be tested are placed in quart (0.95 liter) glass con- -;
tainers fitted with fine mesh screen tops together with ;~ 15-20 houseflies from 1 to 7 days old, and usually from :
2 to 5 days old. The percentage of flies knocked down after 15, 30 and 60 minutes of exposure to the specimens is then recorded.
Outdoor conditions are simulated by coating the ::
insecticlde composition to be tested onto 6205 cm x 43~8 cm sheets of polyester f~lm and air drying them at about ~ ' .
27C. for 16 to 24 hours. Polyvinyl alcohol (10 percent or less by weight) may be used as a binder for compositionsO
.. . .
The specimens are then exposed to ultravlolet light for varying léngths of time in the wavelength range of from ~' about 270 to about 400 nanometers emltted from a General Electric 275 watt sun lamp The sun lamp is positioned about 42 cm away from the specimens, resulting in exposure ~ ~".........
~ 6-~' ' - .
", ,: . , .- . : . .
., of the ins-ecticide composition to a surface temperature of 30-40C. and to light having an intenslty o~ from 1800-2200 microwatts/square centimeter. (~ight intensity of about 1100 microwatts/square centimeter is available outdoors on a clear, sunny summer day at 40 north latitude.) It has been found that ~rhen tested according to ; this procedure, microcapsule compositions of the present lnvention that have as little as about 0.007 mg of pyre-throid per square centimeter of polyester and as little as about 0O005 mg of shell stabilizer per square centi-meter, have long-lived insecticidal activlty.
The following examples are meant to further illustrate, but not limit~ the present invention. All i 15 formulae are glven in parts and percentages by weight unless otherwise noted.
, 36.7 parts of a 20% by weight solution of naturally occurring pyrethroids in deodorized kerosene ~"Premium Pyrocide 175'1), 36~7 parts o~ biological synergist (piperonyl butoxide~g 0.73 parts of flll stabilizer (4-dodecyloxy 2-hydroxyben~ophenone), 0.73 parts of antioxidant (2g6-dioctadecyl-p cresol) and 14.6 parts of polyisocyanate ("Mondur" MRS) are mixed to form a liquid ~ill composition.
A water solution is prepared by adding 54 parts of 17% aqueous polyacrylic acid to 1500 parts of water.
The resultlng solution is ad~usted to a pH of about 7 to 9 with 60 parts of lN sodium hydroxideO
~'~
'.
' The liquid fill (including the polyisocyanate) is then dispersed in the water solution in a mixer (a "Dispersator"*
available from the Presnier Mill Corporation) operated at 3000 rpm. After 5 rninutes of rnixing, 1.5~ parts of polyfurlctional arnine (tetraethylene pentamine) are added over approximately 2.5 minutes. The resulting li~ixture is allowed to react ~or five minutes at room ternperature (approxirnately 25C.) at 3000 rprn. while 'che rnicrocapsule shell walls form. A shell stabili7.er (9.04 parts of 2-hydroxy-4-methoxy-benzophenone-5-sulfonic acid) is added to the dispersion of microcapsules over a 2 mir)ute period and reacted with the available arnine groups of the shell wall. The reaction takes 3-5 minutes and goes to completion. The pH of the composition is maintained at 7-9 by the addition of sodiurn hydroxide. ~
The resulting composition comprises rnicrocapsules ~ ;
(10-30 microns in diameter) each having a polyurea shell containing a photostable ultraviolet light absorbent compound (a shell stabilizer) as an integral part thereof and a liquid fill cornprising a natural pyrethroid, an organic solventl a biological synergist, and antioxidant, and a photostable ultraviolet light absorbent cornpound (a fill stabilizer). The ~-composition is then coated onto polyester, as described above, -at three different coating weights. The first coating has a '`
pyrethroid concentration of 0~105 mg/crn2 and a shell stabilizer concentration of 0~0775 ragtcm2 on the polyester. The second coating has a pyrethroid concentration of ().102 lng/cm2 and a shell stabilizer concentration of 0.170 mg/cm2, and the third a pyrethroid concentration of 0.093 mg/crn2 and a shell *TRADEMARK
. , .
stabilizer concentration of 0.294 mg/cm2 on the polyester.
The samples are then tested for biological activity both initlally and after exposure to 88 hours of slmulated outdoor conditions. In all ~nstances, each sample ~nocks down 100 percent of -the houseflies wi~hin 15 minutes.
The unencapsulated liquid fill used in this example is coated onto polyester to a pyrethroid concen-tration of 0022 mg/cm2. The sample is tested for biological ;~ activity both initially and after 30 hours of exposure to simulated outdoor conditions. It initially knocks down 100 percent of the houseflies within 15 minutes initially but after 30 hours of exposure to simulated outdoor con-ditions, it knocks down 0 percent of the houseflies within 60 minutes.
A microcapsule insecticide composition similar to the above-described microcapsule composition but con-taining no shell stabilizer is coated onto polyester to a pyre~hroid concentration of Ooll mg/cm2. The sample is tested for biological activity both initially and after exposure to 39 hours of simulated outdoor conditionsc It initially has 100 percent knockdown of the houseflies within 15 minutes. After exposure to 39 hours of simulated outdoor conditions, it knocks down 0 percent of the house-flies within 60 minutes.
:
3008 parts of pyrethroid solution ("Premium Pyrocide 175"), 30.8 parts of biological synergist (plperonyl butoxide), U 7 parts of ~ill stabilizer (4-dodecyloxy-2-hydroxybenzophenone) and 0 7 parts of ` -19-,:
;
' . ~,, . ., .: ~
. .. . .... . .
,,. ,.. , " ~
~ 3~ 3~3i antioxidant (2,6-dioctadecyl-p cresol) are mixed to form a liquid fill composition. 12O2 parts of polyl30cyanate ("Mondur" MRS) are added to the ~ill.
A water solution is prepared by adding 54 parts of 17% aqueous polyacrylic acid to 1500 parts of water1 The resulting solution is ad~usted to a pH of about 7 to 9 with 60 parts of lN sodium hydroxlde.
The liquid I'ill (including the polyisocyanate) ; is then dispersed in the water solution in a "Diæpersator"
operated at 3000 rpm. After 5 minutes Or mi~ing, 2.5 parts of polyfunctional amine (tetraethylene pentamine) are added over approximately 2.5 minutes. The resulting mixture is allowed to react for five minutes at room temperature (approximately 25C.) at 3000 rpm. while the microcapsule shell walls ~orm.
A modified amlne is prepared by reacting 15 parts of a shell stabilizer (2-hydroxy-4-methoxybenzo-phenone-5-sulfonic acid) and 7.3 parts of triethanolamine in 40 parts of water at about 25Co for 5 minutes. The modi~ied amlne is then added to the microcapsule compo-sition and mixed therewith ~or about 5 minutes until it coats the microcapsule shell wall.
The resulting composition comprises microcapsules ~ ~
(1-30 microns in diameter) each having a polyurea shell -having a coating with a shell stabilizer physicochemically attached thereto~ and a liquid fill comprising a natural pyrethroid, an organic solvent, a biological synergist~
an antioxidant and a ~ill stabilizer. The composition is then coated onto polyester, as described above, to a pyre-throid concentration of 0.179 mg/cm and a shell stabilizer concentration of 0.248 mg/cm2O
, ',' ''';
-20- ~ -, ' -: ,"
' ,, , ~, . . ..
The composition is tested for biological activity initially and has 100 percent knockdown of the houseflies within 15 minutes~ After exposure to sirnulated outdoor conditions for 80 hours, it provides 100 percent knockdown of the houseflies within 15 minutes. The compo-sition is then stored at room temperature (e.g. 25C.) for 19 days in a glass Jar with some of the storage being under normal room fluorescent lighting and some of the storage being in the darkO After this storage~ the compo-- 10 sition provides 100 percent knockdown of the houseflies within 15 minutesO The composition is then exposed to simulated outdoor con(1itions for an additional 16 hours (making a total of 96 hours of exposure to simulated out-door conditions and 19 days of room temperature storage) and provides 100 percent knockdown of the houseflies l withln 15 minutes. The composition is then stored at room temperature for an additional 165 days (making a total of 96 hours of exposure to simulated outdoor conditions and 184 days o~ room temperature storage) and provides 100 percent knockdown of the houseflies within 15 minutes.
A microcapsule insecticide composition according to the present invention is prepared according to the pro-cedures used in Example 3. The liquid fill comprises ~201 ,! 25 parts of pyrethroid solution ~"Premium Pyrocide"), 22.1 parts of biological synergist (piperonyl butoxide) 7 0.45 .~ .
parts of antioxidant (2,6 dioctadecyl-p-cresol~ 0.45 parts ; of fill stabilizer (4-dodecyloxy-2-hydroxybenzophenone). ~ ;
~; 9 parts of polyisocyanate ("Mondur" MRS~ are added to the .. ' . - ,~ .
,, '~
.. , ' ~
: . , . . . : :
.. , ,-: : , . . .
fill. The liquid fill, including the polyisocyanate, is then dispersed in the water ~olution an~ 1.8 parts of polyfunctional amine are added. After the f`orrnation of` the shell, the resulting microcapsules are filtered from the water phase. The filter cake is then diluted with about 450 parts of ~Jater and 44.1 parts of Fe203 sol (5.3/0 FezO3 by weight colnmercially available under the tradename "L~1-1331"* from ~lalco Chemical Co.) are added to the microcapsule composition and rnixed therewith for about 5 minutes until it coats the microcapsule shell wall.
The resulting composition comprises microcapsules (1-40 rnicrons in diameter) each having a polyurea shell having a coating with a shell stabilizer physicochemically attached thereto, and a liquid fill cornprising a natural pyrethroid, an ,~
organic solvent, a biological synergist, an antioxidant, and a - -fill stabilizer. The composition is then coated onto polyester 9 as described above, to a pyrethroid concentration of ;~
0.186 rng/cm2 and a shell stabilizer concentration of 0.99 -- -rng / c~2 The composition is then tested for biological activity both initially and after exposure to 60 hours of simulated outdoor conditions, The cornposition initially has 100 percent knockdown of the houseflies within 15 minutes. It prcvides 100 percent knockdown of the houseflies within 60 rninutes after 60 ;-~
hous of exposure to sirnulated outdoor conditions.
,'` ' ',, ,. .: .
A microcapsule insecticide composition according to the present invention is prepared according to the -~
*TRAD~MARK -22-l .
.',~' ''" ~ ~ ' ;' ' ~ .
:, , :
." , ~. ., ,,, ;, , , .. : , ~ , , :
procedures used ln Example 1. The liquld ~ill comprlses 37 8 parts pyrethroid solution ("Premium Pyrocide 175"), 37.8 parts biological synergist (plperonyl butoxide), 0O8 parts fill stabilizer (2-hydroxy-4-methoxybenzo-phenone) and Ool parts antioxidant toctadecyl 3-(3'~5'-di-t-butyl-4'-hydroxyphenyl)propionate) Eight parts of polyisocyanate ("Mondur" MRS) are added to the llquid fill.
The liquid fill, including the polyisocyanate, is dis-persed in the water solution and 6 parts of poly~unctional amine (tetraethylene pentamlne~ dissolved in l~ parts of water are added dropwise o~er a 2.5 minute period. After the formation of the shell, 9.3 parts o~ shell stabillzer (2-hydroxy-4 methoxybenzophenone-5-sulfonic acid) in 31 parts of water are added dropwise over a 2 minute period.
1 15 The resulting composition comprises micro-;, capsules (8-15 microns in diameter) each having a polyurea shell containing a shell stabilizer as an integral part thereof and a liquid fill comprising a natural pyrethroid, an organic solvent, a biological synergist, an anti-oxidant and a fill stabilizer. The composition is then Sprayed onto a 100 micron thick circular sheet of poly-~ ester film measuring 57 square centimeters in area. The ; concentration of pyrethrin is 0O0075 mg/cm2. The eoncen-! tratlon of second photostable compound is 0.009 mg/cm2.
The composition is tested for biological activity agalnst German cockroaches both initially and after ex- --:!
i~ posure to simulated outdoor conditions for 16 hours. The - sprayed test sample is placed on a ~lat surface with the .. ..
, sprayed side up. A test cylinder measuring 7.5 centimeters ~ .
in height by 8.52 cm in diameter is placed over the test : ~:
-: .
r -sample. The interior walls of the test cylinder are coated with petroleum ~elly followed by talc. Five German cockroaches that have been starved for one week are placed into the test cylinder and their knockdown is observed. The composition initially has 100 percent knockdown of the cockroaches within 20 minutes. The composition has 100 percent knockdown of the cockroaches Withln 30 minutes after exposure to simulated outdoor conditions for 16 hours. When nonencapsulated pyrethroid ~; 10 compositions are subjected to 16 hours o~ slmulated out-door exposure, they have 0% knockdown of the cockroaches ~ within 30 minutes.
', .
EXAMPhE 5 The outdoor photo and thermal stability and , 15 weatherability of the composition of Example 2 is measured.
Samples of polyester film are coated to a pyrethroid con-centration of 0.102 mg/cm2 and a shell stablllzer concen-tration of 0O102 mgJcm2. The samples are exposed to direct summer sunlight (intensity of about 1100 microwatts/cm2) .. . . .
at an air temperature of from 24C. to 32~C. and are then tested for biological activity both initially and after a total outdoor exposure to direct sunlight of ll3 hours.
~ The composition provides 100 percenk knockdown of the flies !
wlthin 15 minutes, in both cases. ~-!
j A microcapsule insecticide composition according :: } , .
' to the invention is prepared as described in Example lo -, The liquld fill comprises 3602 parts of pyrethroid solution ;~
', ("Premium Pyrocide 175~ 3602 parts of biological synergist " , '~
~:
~ , .
' " .
1 . ,. ~ .
(piperonyl butoxide), 0~7 parts of f`ill stabilizer (4-dodecyloxy~2 hydroxybenzophenone), and 0.7 parts of antioxidant (2,6-dioctadecyl-p-cresol). 14.5 parts of polyisocyar~ate ("Mondur"* MRS) are added to the liquid ~ill.
The liquid f`ill, including the polyisocyanate, is dispersed in the water solution and 2.9 parts of polyfunctional amine (tetraethylene pentamine) are added over a five minute peiod.
After the formation of the shell, 8.9 parts of shell stabilizer (2 hydroxy-4-rnethoxy-benzophenone-5-sulfonic acid) are added over a 2 rninute period.
The resulting composition comprises microcapsules (1-30 ! microns in diarneter) each having a polyurea s'nell containing a shell stabilizer as an integral part thereof and a liquid fill comprising a natural pyrethroid, an organic solvent, a biolo~ical synergist, an antioxidant and a fill stabilizer.
Sustained release properties of compositions of the -preserlt inventiorl are demonstrated by depositing 15 parts of ~R~
the dispersion of this example on each of two No. 5 "Whatman"*
filter papers and washing one of the samples with five successive portions of water (500 parts each) to remove the pyrethroid from the surface of the capsules. Each wash is tested for the presence of pyrethroid by ;neans of ùltraviolet -~
spectroscopy. The absence of pyrethroid is discovered in the -i fifth washing. ~ -'l'he washed and unwashed sampl~s are air dried for 3 ~ hours at 23. and then tested for biological activity.
'~ Both samples knockdown 95% or rnore of` the houseflies within ;
; ~ :, 15 rninutes and 100 percent of` the f'lies within 30 minutes. This illustrates that the shell wall is ~ *TRADMARK -25- ~ -'1: ~ ~ ' '. . , :' ., .
: - . . :: .. - ;.:.:-: . , . : . .
: ~ ~
permeable to the liquid fill thereby allowing it to migrate to the outer surface thereof and maintain an effective level of insecticide thereon.
A microcapsule insecticide composition according to the invention is prepared as described in Example 1.
The liquid fill comprises 36.8 parts of synthe-tic pyre-throid solution ("SBP"-'~138Z( ), and 36.8 parts of biolog-ical synergist (piperonyl butoxide). 14.64 parts of poly-isocyanate ("Mondur"*MRS) are added -to the liquid fill.
The liquid fill, including the polyisocyanate, is dis-persed in the water solution and 2.94 parts of poly-func-' tional amine (tertraethylenepentamine) are added over a :'.
fiveminute period. After the formation of the shell, ... . .
;' 8.82 parts of shell s-tabilizer (2 hydroxy-4-methoxy benzo- :
.j .
~ phenone-5-sulfonic acid) are added over a 2 minute period.
:
~, The resulting composition compr-ises microcapsules .
¦ (1 30 microns in diameter) each having a polyurea shell containing a shell stabilizer as an integral part thereof and a liquid fill comprising a synthetic pyrethroid, an organic solvent and a biological synergist. The composi-.
tion is coated onto polyester film to a pyrethroid con-centration of 0.12 mg/cm2 and a shell stabilizer concen-; tration of o.074 mg/cm . The composition is tested for biological activity both initially and after 15 hours of ,i: :~: .
,:~ :: ~.. , (l) A synthethetic pyrethroid commercially available from S.~. Penick and Co. of New York, New York and comprising 40% by weight (5-bénzyl-3-furyl)methyl-2,2-dime-thyl-3-(2-methylpropenyl!)cyclopropane-carboxy]a-te and 60% by `~ weight aromatic petroleum hydrocarbo~s.
. ~ . .
' *TRADE MARK - 26 -: ' , ~ .
:
~' . , ,. .. ..
, ~ .,, . ., . ,~, . -, ~ , :, .: : :: ,: : .
.. .. . . . .. .. .
exposure to simulated outdoor conditions. It initially provides 100 percent knockdown of houseflies within 15 minutesO It provides 30 percent knockdown of houseflie~
within 60 minutes after exposure to simulated outdoor condltions for 15 hours. Unencapsulated synthetic pyre~
throid compositions have no biological activlty (e.g. 0%
knockdown) after 7 hours of exposure to simulated outdoor conditions.
.
,~ , . .
''1 ' ' ~,, '' :' ~ ,: ' ~ ''' .
`' ;' :,, ~- .. --, . , ., . .. , .. - . . . . .
; 5 the spectrum. Preferably they do not exhibit any substan~
tial chemical reaction with the isocyanate groups and primary aMine groups of the shell forming compounds during ` the microencapsulation process. Among the compounds which can be used as fill stabilizers are substituted benzo-phenones such as 2,4-dihydroxy benzophenone~ 2-hydroxy l~_ methoxy benzophenone, 2-hydroxy-4-octyloxy benzophenone, etc.; ~he benzotriazoles su¢h as 2-(2-hydroxy-5'-methyl-phenyl) benzotriazole, 2-(3',5'-diallyl-2 7 -hydroxylphenyl) benzotriazole, etc.; substituted acrylates such as ethyl 2-cyano-3,3-diphenyl acrylate, 2~ethylhexyl-2-cyano-3,3-diphenyl acetate, etc.; salicylates such as phenyl sali-cylates, 5-butyl phenyl sallcylate, etc.; and nickel organic compounds such as nickel bis (octylphenol) sulfide, ~ etc~ Additional examples of each of these classes of fill `` 20 stabllizers may be found in Kirk-Othmer, Encyclopedia of Chemical Technolo~y, Second Edition~ Volume 21, Inter-science Publishers (1970). The fill stabilizers may com- ~;
prise up to 5 percent, and preferably ~rom about 0~01 to 2 percent, by weight of the microcapsule composition.
The sustained release characteristics and insecticldal lifetime of compositions of the present invention are determined by measuring their biological ~, activity, that is, by determining the percentage of house "~.
- flies ( usca domestlca) that are knocked down a~ter ~arious ~, 30 lengths of exposure to the compositionO As the biological : , :
1,, , ~ ,.... .. .
~ . .
L.a~
; activity of an insectlcide decreases, more exposure time is necessary in order to obtain a given percent knockdown.
Knockdown ls defined to mean a condition of paraiysis and ~i immobilization typically characterized by the insect lying on its back with, at most, intermittent bursts of uncontrolled kicking and spinning motion or sporadlc - crippled and unsuccessful attempts at crawling with llttle or no takeoff or fllghto : Biological activity is determined by means o~
a bioassay test performed both initially (e.g. before the insecticide composition is exposed to simulated outdoor condltions) and after the insecticide composition is exposed to simulated outdoor conditions. In performing the bioassay test, specimens of the insecticide composition ~ -15 to be tested are placed in quart (0.95 liter) glass con- -;
tainers fitted with fine mesh screen tops together with ;~ 15-20 houseflies from 1 to 7 days old, and usually from :
2 to 5 days old. The percentage of flies knocked down after 15, 30 and 60 minutes of exposure to the specimens is then recorded.
Outdoor conditions are simulated by coating the ::
insecticlde composition to be tested onto 6205 cm x 43~8 cm sheets of polyester f~lm and air drying them at about ~ ' .
27C. for 16 to 24 hours. Polyvinyl alcohol (10 percent or less by weight) may be used as a binder for compositionsO
.. . .
The specimens are then exposed to ultravlolet light for varying léngths of time in the wavelength range of from ~' about 270 to about 400 nanometers emltted from a General Electric 275 watt sun lamp The sun lamp is positioned about 42 cm away from the specimens, resulting in exposure ~ ~".........
~ 6-~' ' - .
", ,: . , .- . : . .
., of the ins-ecticide composition to a surface temperature of 30-40C. and to light having an intenslty o~ from 1800-2200 microwatts/square centimeter. (~ight intensity of about 1100 microwatts/square centimeter is available outdoors on a clear, sunny summer day at 40 north latitude.) It has been found that ~rhen tested according to ; this procedure, microcapsule compositions of the present lnvention that have as little as about 0.007 mg of pyre-throid per square centimeter of polyester and as little as about 0O005 mg of shell stabilizer per square centi-meter, have long-lived insecticidal activlty.
The following examples are meant to further illustrate, but not limit~ the present invention. All i 15 formulae are glven in parts and percentages by weight unless otherwise noted.
, 36.7 parts of a 20% by weight solution of naturally occurring pyrethroids in deodorized kerosene ~"Premium Pyrocide 175'1), 36~7 parts o~ biological synergist (piperonyl butoxide~g 0.73 parts of flll stabilizer (4-dodecyloxy 2-hydroxyben~ophenone), 0.73 parts of antioxidant (2g6-dioctadecyl-p cresol) and 14.6 parts of polyisocyanate ("Mondur" MRS) are mixed to form a liquid ~ill composition.
A water solution is prepared by adding 54 parts of 17% aqueous polyacrylic acid to 1500 parts of water.
The resultlng solution is ad~usted to a pH of about 7 to 9 with 60 parts of lN sodium hydroxideO
~'~
'.
' The liquid fill (including the polyisocyanate) is then dispersed in the water solution in a mixer (a "Dispersator"*
available from the Presnier Mill Corporation) operated at 3000 rpm. After 5 rninutes of rnixing, 1.5~ parts of polyfurlctional arnine (tetraethylene pentamine) are added over approximately 2.5 minutes. The resulting li~ixture is allowed to react ~or five minutes at room ternperature (approxirnately 25C.) at 3000 rprn. while 'che rnicrocapsule shell walls form. A shell stabili7.er (9.04 parts of 2-hydroxy-4-methoxy-benzophenone-5-sulfonic acid) is added to the dispersion of microcapsules over a 2 mir)ute period and reacted with the available arnine groups of the shell wall. The reaction takes 3-5 minutes and goes to completion. The pH of the composition is maintained at 7-9 by the addition of sodiurn hydroxide. ~
The resulting composition comprises rnicrocapsules ~ ;
(10-30 microns in diameter) each having a polyurea shell containing a photostable ultraviolet light absorbent compound (a shell stabilizer) as an integral part thereof and a liquid fill cornprising a natural pyrethroid, an organic solventl a biological synergist, and antioxidant, and a photostable ultraviolet light absorbent cornpound (a fill stabilizer). The ~-composition is then coated onto polyester, as described above, -at three different coating weights. The first coating has a '`
pyrethroid concentration of 0~105 mg/crn2 and a shell stabilizer concentration of 0~0775 ragtcm2 on the polyester. The second coating has a pyrethroid concentration of ().102 lng/cm2 and a shell stabilizer concentration of 0.170 mg/cm2, and the third a pyrethroid concentration of 0.093 mg/crn2 and a shell *TRADEMARK
. , .
stabilizer concentration of 0.294 mg/cm2 on the polyester.
The samples are then tested for biological activity both initlally and after exposure to 88 hours of slmulated outdoor conditions. In all ~nstances, each sample ~nocks down 100 percent of -the houseflies wi~hin 15 minutes.
The unencapsulated liquid fill used in this example is coated onto polyester to a pyrethroid concen-tration of 0022 mg/cm2. The sample is tested for biological ;~ activity both initially and after 30 hours of exposure to simulated outdoor conditions. It initially knocks down 100 percent of the houseflies within 15 minutes initially but after 30 hours of exposure to simulated outdoor con-ditions, it knocks down 0 percent of the houseflies within 60 minutes.
A microcapsule insecticide composition similar to the above-described microcapsule composition but con-taining no shell stabilizer is coated onto polyester to a pyre~hroid concentration of Ooll mg/cm2. The sample is tested for biological activity both initially and after exposure to 39 hours of simulated outdoor conditionsc It initially has 100 percent knockdown of the houseflies within 15 minutes. After exposure to 39 hours of simulated outdoor conditions, it knocks down 0 percent of the house-flies within 60 minutes.
:
3008 parts of pyrethroid solution ("Premium Pyrocide 175"), 30.8 parts of biological synergist (plperonyl butoxide), U 7 parts of ~ill stabilizer (4-dodecyloxy-2-hydroxybenzophenone) and 0 7 parts of ` -19-,:
;
' . ~,, . ., .: ~
. .. . .... . .
,,. ,.. , " ~
~ 3~ 3~3i antioxidant (2,6-dioctadecyl-p cresol) are mixed to form a liquid fill composition. 12O2 parts of polyl30cyanate ("Mondur" MRS) are added to the ~ill.
A water solution is prepared by adding 54 parts of 17% aqueous polyacrylic acid to 1500 parts of water1 The resulting solution is ad~usted to a pH of about 7 to 9 with 60 parts of lN sodium hydroxlde.
The liquid I'ill (including the polyisocyanate) ; is then dispersed in the water solution in a "Diæpersator"
operated at 3000 rpm. After 5 minutes Or mi~ing, 2.5 parts of polyfunctional amine (tetraethylene pentamine) are added over approximately 2.5 minutes. The resulting mixture is allowed to react for five minutes at room temperature (approximately 25C.) at 3000 rpm. while the microcapsule shell walls ~orm.
A modified amlne is prepared by reacting 15 parts of a shell stabilizer (2-hydroxy-4-methoxybenzo-phenone-5-sulfonic acid) and 7.3 parts of triethanolamine in 40 parts of water at about 25Co for 5 minutes. The modi~ied amlne is then added to the microcapsule compo-sition and mixed therewith ~or about 5 minutes until it coats the microcapsule shell wall.
The resulting composition comprises microcapsules ~ ~
(1-30 microns in diameter) each having a polyurea shell -having a coating with a shell stabilizer physicochemically attached thereto~ and a liquid fill comprising a natural pyrethroid, an organic solvent, a biological synergist~
an antioxidant and a ~ill stabilizer. The composition is then coated onto polyester, as described above, to a pyre-throid concentration of 0.179 mg/cm and a shell stabilizer concentration of 0.248 mg/cm2O
, ',' ''';
-20- ~ -, ' -: ,"
' ,, , ~, . . ..
The composition is tested for biological activity initially and has 100 percent knockdown of the houseflies within 15 minutes~ After exposure to sirnulated outdoor conditions for 80 hours, it provides 100 percent knockdown of the houseflies within 15 minutes. The compo-sition is then stored at room temperature (e.g. 25C.) for 19 days in a glass Jar with some of the storage being under normal room fluorescent lighting and some of the storage being in the darkO After this storage~ the compo-- 10 sition provides 100 percent knockdown of the houseflies within 15 minutesO The composition is then exposed to simulated outdoor con(1itions for an additional 16 hours (making a total of 96 hours of exposure to simulated out-door conditions and 19 days of room temperature storage) and provides 100 percent knockdown of the houseflies l withln 15 minutes. The composition is then stored at room temperature for an additional 165 days (making a total of 96 hours of exposure to simulated outdoor conditions and 184 days o~ room temperature storage) and provides 100 percent knockdown of the houseflies within 15 minutes.
A microcapsule insecticide composition according to the present invention is prepared according to the pro-cedures used in Example 3. The liquid fill comprises ~201 ,! 25 parts of pyrethroid solution ~"Premium Pyrocide"), 22.1 parts of biological synergist (piperonyl butoxide) 7 0.45 .~ .
parts of antioxidant (2,6 dioctadecyl-p-cresol~ 0.45 parts ; of fill stabilizer (4-dodecyloxy-2-hydroxybenzophenone). ~ ;
~; 9 parts of polyisocyanate ("Mondur" MRS~ are added to the .. ' . - ,~ .
,, '~
.. , ' ~
: . , . . . : :
.. , ,-: : , . . .
fill. The liquid fill, including the polyisocyanate, is then dispersed in the water ~olution an~ 1.8 parts of polyfunctional amine are added. After the f`orrnation of` the shell, the resulting microcapsules are filtered from the water phase. The filter cake is then diluted with about 450 parts of ~Jater and 44.1 parts of Fe203 sol (5.3/0 FezO3 by weight colnmercially available under the tradename "L~1-1331"* from ~lalco Chemical Co.) are added to the microcapsule composition and rnixed therewith for about 5 minutes until it coats the microcapsule shell wall.
The resulting composition comprises microcapsules (1-40 rnicrons in diameter) each having a polyurea shell having a coating with a shell stabilizer physicochemically attached thereto, and a liquid fill cornprising a natural pyrethroid, an ,~
organic solvent, a biological synergist, an antioxidant, and a - -fill stabilizer. The composition is then coated onto polyester 9 as described above, to a pyrethroid concentration of ;~
0.186 rng/cm2 and a shell stabilizer concentration of 0.99 -- -rng / c~2 The composition is then tested for biological activity both initially and after exposure to 60 hours of simulated outdoor conditions, The cornposition initially has 100 percent knockdown of the houseflies within 15 minutes. It prcvides 100 percent knockdown of the houseflies within 60 rninutes after 60 ;-~
hous of exposure to sirnulated outdoor conditions.
,'` ' ',, ,. .: .
A microcapsule insecticide composition according to the present invention is prepared according to the -~
*TRAD~MARK -22-l .
.',~' ''" ~ ~ ' ;' ' ~ .
:, , :
." , ~. ., ,,, ;, , , .. : , ~ , , :
procedures used ln Example 1. The liquld ~ill comprlses 37 8 parts pyrethroid solution ("Premium Pyrocide 175"), 37.8 parts biological synergist (plperonyl butoxide), 0O8 parts fill stabilizer (2-hydroxy-4-methoxybenzo-phenone) and Ool parts antioxidant toctadecyl 3-(3'~5'-di-t-butyl-4'-hydroxyphenyl)propionate) Eight parts of polyisocyanate ("Mondur" MRS) are added to the llquid fill.
The liquid fill, including the polyisocyanate, is dis-persed in the water solution and 6 parts of poly~unctional amine (tetraethylene pentamlne~ dissolved in l~ parts of water are added dropwise o~er a 2.5 minute period. After the formation of the shell, 9.3 parts o~ shell stabillzer (2-hydroxy-4 methoxybenzophenone-5-sulfonic acid) in 31 parts of water are added dropwise over a 2 minute period.
1 15 The resulting composition comprises micro-;, capsules (8-15 microns in diameter) each having a polyurea shell containing a shell stabilizer as an integral part thereof and a liquid fill comprising a natural pyrethroid, an organic solvent, a biological synergist, an anti-oxidant and a fill stabilizer. The composition is then Sprayed onto a 100 micron thick circular sheet of poly-~ ester film measuring 57 square centimeters in area. The ; concentration of pyrethrin is 0O0075 mg/cm2. The eoncen-! tratlon of second photostable compound is 0.009 mg/cm2.
The composition is tested for biological activity agalnst German cockroaches both initially and after ex- --:!
i~ posure to simulated outdoor conditions for 16 hours. The - sprayed test sample is placed on a ~lat surface with the .. ..
, sprayed side up. A test cylinder measuring 7.5 centimeters ~ .
in height by 8.52 cm in diameter is placed over the test : ~:
-: .
r -sample. The interior walls of the test cylinder are coated with petroleum ~elly followed by talc. Five German cockroaches that have been starved for one week are placed into the test cylinder and their knockdown is observed. The composition initially has 100 percent knockdown of the cockroaches within 20 minutes. The composition has 100 percent knockdown of the cockroaches Withln 30 minutes after exposure to simulated outdoor conditions for 16 hours. When nonencapsulated pyrethroid ~; 10 compositions are subjected to 16 hours o~ slmulated out-door exposure, they have 0% knockdown of the cockroaches ~ within 30 minutes.
', .
EXAMPhE 5 The outdoor photo and thermal stability and , 15 weatherability of the composition of Example 2 is measured.
Samples of polyester film are coated to a pyrethroid con-centration of 0.102 mg/cm2 and a shell stablllzer concen-tration of 0O102 mgJcm2. The samples are exposed to direct summer sunlight (intensity of about 1100 microwatts/cm2) .. . . .
at an air temperature of from 24C. to 32~C. and are then tested for biological activity both initially and after a total outdoor exposure to direct sunlight of ll3 hours.
~ The composition provides 100 percenk knockdown of the flies !
wlthin 15 minutes, in both cases. ~-!
j A microcapsule insecticide composition according :: } , .
' to the invention is prepared as described in Example lo -, The liquld fill comprises 3602 parts of pyrethroid solution ;~
', ("Premium Pyrocide 175~ 3602 parts of biological synergist " , '~
~:
~ , .
' " .
1 . ,. ~ .
(piperonyl butoxide), 0~7 parts of f`ill stabilizer (4-dodecyloxy~2 hydroxybenzophenone), and 0.7 parts of antioxidant (2,6-dioctadecyl-p-cresol). 14.5 parts of polyisocyar~ate ("Mondur"* MRS) are added to the liquid ~ill.
The liquid f`ill, including the polyisocyanate, is dispersed in the water solution and 2.9 parts of polyfunctional amine (tetraethylene pentamine) are added over a five minute peiod.
After the formation of the shell, 8.9 parts of shell stabilizer (2 hydroxy-4-rnethoxy-benzophenone-5-sulfonic acid) are added over a 2 rninute period.
The resulting composition comprises microcapsules (1-30 ! microns in diarneter) each having a polyurea s'nell containing a shell stabilizer as an integral part thereof and a liquid fill comprising a natural pyrethroid, an organic solvent, a biolo~ical synergist, an antioxidant and a fill stabilizer.
Sustained release properties of compositions of the -preserlt inventiorl are demonstrated by depositing 15 parts of ~R~
the dispersion of this example on each of two No. 5 "Whatman"*
filter papers and washing one of the samples with five successive portions of water (500 parts each) to remove the pyrethroid from the surface of the capsules. Each wash is tested for the presence of pyrethroid by ;neans of ùltraviolet -~
spectroscopy. The absence of pyrethroid is discovered in the -i fifth washing. ~ -'l'he washed and unwashed sampl~s are air dried for 3 ~ hours at 23. and then tested for biological activity.
'~ Both samples knockdown 95% or rnore of` the houseflies within ;
; ~ :, 15 rninutes and 100 percent of` the f'lies within 30 minutes. This illustrates that the shell wall is ~ *TRADMARK -25- ~ -'1: ~ ~ ' '. . , :' ., .
: - . . :: .. - ;.:.:-: . , . : . .
: ~ ~
permeable to the liquid fill thereby allowing it to migrate to the outer surface thereof and maintain an effective level of insecticide thereon.
A microcapsule insecticide composition according to the invention is prepared as described in Example 1.
The liquid fill comprises 36.8 parts of synthe-tic pyre-throid solution ("SBP"-'~138Z( ), and 36.8 parts of biolog-ical synergist (piperonyl butoxide). 14.64 parts of poly-isocyanate ("Mondur"*MRS) are added -to the liquid fill.
The liquid fill, including the polyisocyanate, is dis-persed in the water solution and 2.94 parts of poly-func-' tional amine (tertraethylenepentamine) are added over a :'.
fiveminute period. After the formation of the shell, ... . .
;' 8.82 parts of shell s-tabilizer (2 hydroxy-4-methoxy benzo- :
.j .
~ phenone-5-sulfonic acid) are added over a 2 minute period.
:
~, The resulting composition compr-ises microcapsules .
¦ (1 30 microns in diameter) each having a polyurea shell containing a shell stabilizer as an integral part thereof and a liquid fill comprising a synthetic pyrethroid, an organic solvent and a biological synergist. The composi-.
tion is coated onto polyester film to a pyrethroid con-centration of 0.12 mg/cm2 and a shell stabilizer concen-; tration of o.074 mg/cm . The composition is tested for biological activity both initially and after 15 hours of ,i: :~: .
,:~ :: ~.. , (l) A synthethetic pyrethroid commercially available from S.~. Penick and Co. of New York, New York and comprising 40% by weight (5-bénzyl-3-furyl)methyl-2,2-dime-thyl-3-(2-methylpropenyl!)cyclopropane-carboxy]a-te and 60% by `~ weight aromatic petroleum hydrocarbo~s.
. ~ . .
' *TRADE MARK - 26 -: ' , ~ .
:
~' . , ,. .. ..
, ~ .,, . ., . ,~, . -, ~ , :, .: : :: ,: : .
.. .. . . . .. .. .
exposure to simulated outdoor conditions. It initially provides 100 percent knockdown of houseflies within 15 minutesO It provides 30 percent knockdown of houseflie~
within 60 minutes after exposure to simulated outdoor condltions for 15 hours. Unencapsulated synthetic pyre~
throid compositions have no biological activlty (e.g. 0%
knockdown) after 7 hours of exposure to simulated outdoor conditions.
.
,~ , . .
''1 ' ' ~,, '' :' ~ ,: ' ~ ''' .
`' ;' :,, ~- .. --, . , ., . .. , .. - . . . . .
Claims (11)
1. A microcapsule insecticide composition com-prising microcapsules each having a polyurea shell including as an integral part of said shell a photostable ultraviolet light absorbent compound having a log molar extinction coefficient of from about 2 to 5 with respect to radiation having wave lengths in the range of from about 270 to 350 nanometers and a liquid fill capable of slowly permeating the shell and comprising a pyrethroid and a biological synergist therefor.
2. A composition according to claim 1 containing a benzophenone substituted with an acidic group having a dissociation constant greater than 1 x 10-6 or a benzo-phenone substituted with a group containing at least one active hydrogen as an integral part of said shell.
3. A composition of claim 2 wherein said acid-substituted benzophenone is 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid or where said benzophenone containing at least one active hydrogen is 2 amino-5-chlorobenzophenone.
4. A composition according to claim 3 wherein said biological synergist comprises 3,4-methylenedioxy-6-propylbenxyl butyldiethylene glycol ether.
5. A composition according to claim 1 further containing an antioxidant, a water-immiscible organic solvent and an ultraviolet light absorbent com-pound having a log molar extinction coefficient of from about 2 to 5 with respect to radiation having wave lengths in the range of from 270 to 350 nanometers in said liquid fill.
6. A composition according to claim 5 wherein said antioxidant comprises an alkylated phenol.
7. A composition according to claim 6 containing octadecyl 3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate in said liquid fill.
8. A composition according to claim 7 wherein said water-immiscible solvent is deodorized kerosene.
9. A composition according to claim 8 wherein said ultraviolet light absorbent compound is a benzophenone.
10. A composition according to claim 9 wherein said benzophenone is 2-hydroxy-4-methoxybenzophenone.
11. The method of controlling insect pest activity comprising contacting said insects with a microcapsule insecticide composition comprising microcapsules each having a polyurea shell including as an integral part of said shell a photostable ultraviolet light absorbent compound having a log molar extinction coefficient of from about 2 to 5 with respect to radiation having wave lengths in the range of from about 270 to 350 nanometers and a liquid fill capable of slowly permeating the shell and comprising a pyrethroid and a biological synergist therefor.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US56628775A | 1975-04-09 | 1975-04-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1044134A true CA1044134A (en) | 1978-12-12 |
Family
ID=24262263
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA248,015A Expired CA1044134A (en) | 1975-04-09 | 1976-03-16 | Microcapsule insecticide composition |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS51133419A (en) |
| CA (1) | CA1044134A (en) |
| DE (1) | DE2615646A1 (en) |
| FR (1) | FR2306634A1 (en) |
| GB (1) | GB1513614A (en) |
| IT (1) | IT1058102B (en) |
| MX (1) | MX4469E (en) |
| ZA (1) | ZA762109B (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6080418A (en) * | 1997-04-07 | 2000-06-27 | 3M Innovative Properties Company | Suspensions of microcapsules containing biologically active ingredients and adhesive microspheres |
| US6248364B1 (en) | 1997-04-07 | 2001-06-19 | 3M Innovative Properties Company | Encapsulation process and encapsulated products |
| US6365189B1 (en) | 1999-10-22 | 2002-04-02 | 3M Innovative Properties Company | Method of delivering and releasing a pheromone |
| US6375968B1 (en) | 1999-10-22 | 2002-04-23 | 3M Innovative Properties Company | Encapsulated active material immobilized in hydrogel microbeads |
| US6793937B2 (en) | 1999-10-22 | 2004-09-21 | 3M Innovative Properties Company | Method of delivering active material within hydrogel microbeads |
| US7179480B2 (en) | 2002-04-24 | 2007-02-20 | 3M Innovative Properties Company | Sustained release microcapsules |
| US9079152B2 (en) | 2003-05-11 | 2015-07-14 | Ben Gurion University Of The Negev Research And Development Authority | Encapsulated essential oils |
Families Citing this family (34)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1592691A (en) | 1976-10-05 | 1981-07-08 | Ici Australia Ltd | Stabilised tickicidal compositions |
| JPS5455726A (en) * | 1977-10-07 | 1979-05-04 | Sumitomo Chem Co Ltd | Pyrethroid insecticide |
| US4280833A (en) * | 1979-03-26 | 1981-07-28 | Monsanto Company | Encapsulation by interfacial polycondensation, and aqueous herbicidal composition containing microcapsules produced thereby |
| US4301154A (en) * | 1979-10-01 | 1981-11-17 | The Dow Chemical Company | Insecticidal synergistic mixtures of 0,0-diethyl 0-(3,5,6-trichloro-2-pyridinyl)phosphorothioate and 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane carboxylic acid:cyano(6-phenoxy-2-pyridinyl)methyl ester |
| US4301155A (en) * | 1979-10-01 | 1981-11-17 | The Dow Chemical Company | Insecticidal synergistic mixtures of O,O-diethyl O-(3,5,6-trichloro-2-pyridinyl)phosphorothioate and 2,2,3,3-tetramethylcyclopropanecarboxylic acid:cyano(3-phenoxyphenyl)methyl ester |
| US4301156A (en) * | 1979-10-01 | 1981-11-17 | The Dow Chemical Company | Insecticidal synergistic mixtures of O,O-diethyl O-(3,5,6-trichloro-2-pyridinyl) phosphorothioate and 4-chloro-α-(1-methylethyl)benzeneacetic acid:cyano (6-phenoxy-2-pyridinyl)methyl ester |
| GR75114B (en) * | 1981-02-02 | 1984-07-13 | Albany Int Corp | |
| DE3230273A1 (en) * | 1982-08-14 | 1984-02-16 | Bayer Ag, 5090 Leverkusen | LIGHT-STABILIZED CHINOXALINE DI-N-OXIDES |
| US4670246A (en) * | 1984-11-05 | 1987-06-02 | Pennwalt Corporation | Microencapsulated pyrethroids |
| FR2591227B1 (en) * | 1985-12-06 | 1988-11-10 | Pasteur Institut | PEPTIDES CAPABLE OF INHIBITING INTERACTIONS BETWEEN LAV VIRUSES AND T4 LYMPHOCYTES, DERIVATIVES THEREOF AND THEIR APPLICATIONS |
| GB8603061D0 (en) * | 1986-02-07 | 1986-03-12 | Wellcome Found | Pesticidal formulations |
| US5229122A (en) * | 1986-02-07 | 1993-07-20 | Burroughs Wellcome Co. | Pesticidal compositions |
| SE468740B (en) * | 1986-03-17 | 1993-03-15 | Sumitomo Chemical Co | MICROINCAPTED INSECTICID AND / OR ACARICID PYRETROID COMPOSITION, SET TO REGULATE INSECTS AND / OR ANIMALS THEREOF AND PROCEDURES FOR PREPARING THEREOF |
| JPH0818926B2 (en) * | 1987-07-20 | 1996-02-28 | 日本化薬株式会社 | Pesticide microcapsule manufacturing method |
| US5591727A (en) * | 1990-09-12 | 1997-01-07 | Perycut-Chemie Ag | Insecticidal composition |
| GB9411115D0 (en) * | 1994-06-03 | 1994-07-27 | Secr Defence | Stabilisation of photosensitive material |
| DE19530076A1 (en) * | 1995-08-16 | 1997-02-20 | Bayer Ag | Composition with insecticidal action |
| GB0129976D0 (en) * | 2001-12-14 | 2002-02-06 | Mars Inc | Treatment method |
| GB0209749D0 (en) | 2002-04-29 | 2002-06-05 | Rothamsted Ex Res Station | Compositions and methods |
| DE10223916A1 (en) | 2002-05-29 | 2003-12-11 | Bayer Cropscience Ag | Microcapsule formulations |
| GB0219610D0 (en) | 2002-08-22 | 2002-10-02 | Syngenta Ltd | Composition |
| GB0219611D0 (en) * | 2002-08-22 | 2002-10-02 | Syngenta Ltd | Composition |
| JP4289870B2 (en) * | 2002-11-08 | 2009-07-01 | 住化エンビロサイエンス株式会社 | Insecticidal composition |
| JP4750804B2 (en) | 2005-02-24 | 2011-08-17 | シンジェンタ パーティシペーションズ アクチェンゲゼルシャフト | Capsule formulation |
| US10149478B2 (en) | 2005-04-22 | 2018-12-11 | Endura S.P.A. | Biologically active formulation |
| ITMI20050729A1 (en) | 2005-04-22 | 2006-10-23 | Endura Spa | NEW BIOLOGICALLY ACTIVE FORMULATION |
| ITMI20050728A1 (en) * | 2005-04-22 | 2006-10-23 | Endura Spa | INNOVATIVE FORMULATION |
| GB0804700D0 (en) * | 2008-03-13 | 2008-04-16 | Syngenta Ltd | Microencapsulation |
| PT104692B (en) * | 2009-07-29 | 2013-06-18 | Univ Do Minho | PHOTOCATALITICAL COATING FOR CONTROLLED RELEASE OF VOLATILE AGENTS |
| TWI556737B (en) * | 2011-02-11 | 2016-11-11 | 陶氏農業科學公司 | Improved insecticide formulations |
| ES2527187T3 (en) | 2011-11-04 | 2015-01-21 | Endura S.P.A. | Microcapsules comprising a pyrethroid and / or a neonicotinoid and a synergistic agent |
| AU2013281755B2 (en) * | 2012-06-26 | 2016-12-01 | Sumitomo Chemical Company, Limited | Microcapsule |
| PT108665B (en) | 2015-07-05 | 2020-11-02 | Universidade Do Minho | MICRO OR NANOCAPSULES WITH PHOTOCATALYTIC PROPERTIES FOR CONTROLLED RELEASE OF DIFFUSING AGENTS AND THEIR METHOD OF OBTAINING |
| CN111013506B (en) * | 2019-12-30 | 2022-04-19 | 杭州传化精细化工有限公司 | Microcapsule emulsion of micromolecular anti-aging agent with degradable capsule wall and preparation method and application thereof |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2090109A (en) * | 1933-11-15 | 1937-08-17 | Mayne R Coe | Stabilized insecticide of plant origin |
| FR861309A (en) * | 1939-11-03 | 1941-02-06 | Insecticide improvement | |
| GB929405A (en) * | 1958-12-22 | 1963-06-19 | Upjohn Co | Processes for the encapsulation of particles |
| US3063893A (en) * | 1959-11-24 | 1962-11-13 | Kenya Pyrethrum Board | Stabilized pyrethrum compositions |
| US3264176A (en) * | 1963-02-11 | 1966-08-02 | Leeco Chemical Company Divisio | Ultraviolet light stable synergistic pyrethrum compositions |
| US3577515A (en) * | 1963-12-13 | 1971-05-04 | Pennwalt Corp | Encapsulation by interfacial polycondensation |
| US3516941A (en) * | 1966-07-25 | 1970-06-23 | Minnesota Mining & Mfg | Microcapsules and process of making |
| US3560613A (en) * | 1967-05-09 | 1971-02-02 | Us Agriculture | Stabilization of pyrethroid compositions |
| US3541203A (en) * | 1969-05-08 | 1970-11-17 | Ncr Co | Protected virus composition for insect control |
| US3839561A (en) * | 1970-07-22 | 1974-10-01 | Scm Corp | Insecticidal compositions stabilized by certain diisophorone derivatives |
| CA1104882A (en) * | 1972-03-15 | 1981-07-14 | Herbert B. Scher | Encapsulation process |
| DE2411373A1 (en) * | 1974-03-09 | 1975-09-11 | Ekof Erz Und Kohleflotation Gm | Pest control with pyrethrin and pyrethroids - in microencapsulated form, opt. together with synergists |
-
1976
- 1976-03-16 CA CA248,015A patent/CA1044134A/en not_active Expired
- 1976-04-08 JP JP51039772A patent/JPS51133419A/en active Granted
- 1976-04-08 FR FR7610243A patent/FR2306634A1/en active Granted
- 1976-04-08 DE DE19762615646 patent/DE2615646A1/en not_active Ceased
- 1976-04-08 MX MX76155U patent/MX4469E/en unknown
- 1976-04-08 IT IT48932/76A patent/IT1058102B/en active
- 1976-04-08 GB GB14383/76A patent/GB1513614A/en not_active Expired
- 1976-04-08 ZA ZA762109A patent/ZA762109B/en unknown
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6080418A (en) * | 1997-04-07 | 2000-06-27 | 3M Innovative Properties Company | Suspensions of microcapsules containing biologically active ingredients and adhesive microspheres |
| US6248364B1 (en) | 1997-04-07 | 2001-06-19 | 3M Innovative Properties Company | Encapsulation process and encapsulated products |
| US6365189B1 (en) | 1999-10-22 | 2002-04-02 | 3M Innovative Properties Company | Method of delivering and releasing a pheromone |
| US6375968B1 (en) | 1999-10-22 | 2002-04-23 | 3M Innovative Properties Company | Encapsulated active material immobilized in hydrogel microbeads |
| US6793937B2 (en) | 1999-10-22 | 2004-09-21 | 3M Innovative Properties Company | Method of delivering active material within hydrogel microbeads |
| US7179480B2 (en) | 2002-04-24 | 2007-02-20 | 3M Innovative Properties Company | Sustained release microcapsules |
| US9079152B2 (en) | 2003-05-11 | 2015-07-14 | Ben Gurion University Of The Negev Research And Development Authority | Encapsulated essential oils |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2306634A1 (en) | 1976-11-05 |
| FR2306634B1 (en) | 1980-01-11 |
| DE2615646A1 (en) | 1976-10-14 |
| MX4469E (en) | 1982-05-18 |
| ZA762109B (en) | 1977-04-27 |
| AU1281176A (en) | 1977-10-06 |
| JPS5542964B2 (en) | 1980-11-04 |
| GB1513614A (en) | 1978-06-07 |
| IT1058102B (en) | 1982-04-10 |
| JPS51133419A (en) | 1976-11-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1044134A (en) | Microcapsule insecticide composition | |
| US4056610A (en) | Microcapsule insecticide composition | |
| CA1179682A (en) | Stabilised compositions containing behaviour modifying compounds | |
| FI80822C (en) | INKAPSLINGSFOERFARANDE SAMT GENOM FOERFARANDET FRAMSTAELLD, MIKROKAPSLAR INNEHAOLLANDE INSEKTISIDKOMPOSITION. | |
| US3959464A (en) | Microencapsulated methyl and ethyl parathion insecticide in aqueous carrier | |
| US4309213A (en) | Process of encapsulation by interfacial polycondensation | |
| DE69814846T2 (en) | CAPSULE METHOD AND ENCLOSED PRODUCTS | |
| DE3032616C2 (en) | ||
| JP2005528200A (en) | Method for encapsulating hydrophobic organic molecules in polyurea capsules | |
| HRP960472A2 (en) | Microencapsuled insecticide preparations and a process for the preparation thereof | |
| EP1447003B1 (en) | Pest controlling | |
| BG63522B1 (en) | Microcapsules containing suspensions of biologically active compounds and a protection device from ultra violet light | |
| EP0823993A2 (en) | PH-sensitive microcapsules | |
| CA1308019C (en) | Vermin-repellent microcapsules with slow-release potentiality | |
| DE60201339T2 (en) | STABILIZED ACTIVE ACTIVE SUBSTANCES | |
| US5549903A (en) | Microencapsulated composition containing chlorpyrifos or endosulfsan | |
| SU1535365A3 (en) | Microcapsule | |
| KR890001144B1 (en) | Contnelled release aquatic biologically active agent formulations | |
| JP4289870B2 (en) | Insecticidal composition | |
| EP3014994B1 (en) | Microcapsules for thermal transpiration | |
| US3335051A (en) | Selected n-substituted piperazines and morpholines as bird repellents | |
| JP2003335604A (en) | Microcapsule of oil soluble agrochemically active ingredient and method for producing the same | |
| JP2018104606A (en) | Coating composition, coated film and article | |
| AU710988B2 (en) | Pesticidal composition | |
| DD142274A5 (en) | HERBICIDAL AGENT |