WO2004077948A1

WO2004077948A1 - Agricultural-chemical microcapsule preparation made by oil/water liquid drying and process for producing the same

Info

Publication number: WO2004077948A1
Application number: PCT/JP2003/016351
Authority: WO
Inventors: Yoshinobu Kawano; Yasuo Hatate; Koichiro Shiomori; Masami Mizuno; Masahiro Suzuki
Original assignee: Nippon Soda Co., Ltd.
Priority date: 2002-12-19
Filing date: 2003-12-19
Publication date: 2004-09-16
Also published as: AU2003289444A1; JP4723864B2; JPWO2004077948A1

Abstract

A process for easily producing microcapsules, characterized by comprising the following steps; and a composite microcapsule preparation produced by the process which contains an agricultural-chemical active ingredient in a large amount. (1) A step in which one or more agricultural-chemical active ingredients and polylactic acid or the like are dissolved in a solvent in which they are soluble and which is incompatible with water. (2) A step in which the solution obtained in the preceding step is emulsified/dispersed in water by means of a homomixer or homogenizer. (3) A step in which the solvent contained in the solution emulsified/dispersed is evaporated and removed by heating under vacuum to crystallize the agricultural-chemical active ingredients and polymer. (4) A step in which the composite microcapsule preparation thus formed by solidification is taken out by decantation and/or centrifugal separation.

Description

Agrochemical micro force capsule formulation by Oil / Water in-liquid drying method and its manufacturing method

The present invention relates to a microcapsule preparation of an agrochemical active ingredient, in particular, a cyclohexanedione herbicide or an azole bactericide, and a method for producing the same.

Akira Background technology

Many methods are already known for microencapsulation techniques for pharmaceuticals, pesticides, and the like. (See, for example, Non-Patent Document 1).

Also, a method for producing a microcapsule preparation similar to the method of the present invention is known.

(See Patent Document 1 and Patent Document 2)

However, there was no known simple method for producing microcapsule preparations, which has a high production efficiency of the hexoxanedione herbicide or lysole fungicide and has a high concentration of the pesticide active ingredient in the microcapsule preparation. .

Non-Patent Document 1: “Basic Granulation and Engineering of Granulation”, “Granulation Handbook” (1991), edited by Japan Powder Industry Technical Association, Ohmsha Co., Ltd., 60-64 pages Patent Document 1: See Japanese Patent Application Laid-Open No. 6-65-064

Patent Document 2: Japanese Unexamined Patent Application Publication No. 2000-30013 Disclosure of the Invention

An object of the present invention is to provide a microcapsule preparation in which a large amount of a pesticidal active ingredient is incorporated into microcapsules and which can be easily produced, and a method for producing the same. The present invention relates to a method for producing a microforce capsule comprising the following steps, and a microcapsule preparation obtained by the method.

(1) One or more coatings of one or more pesticidal active ingredients and styrene-dibutylbenzene copolymer, polyepsilon-based prolactam, polylactic acid, or a copolymer of polylactic acid and glycolic acid Dissolve them in a mixture with the forming polymer Dissolving in a solvent that is incompatible with water.

(2) A step of emulsifying and dispersing the solution obtained in the preceding step in water using a homomixer or a homogenizer.

(3) Heating the solvent in the emulsified and dispersed solution >> a step of crystallizing the pesticidally active component and the polymer by evaporating under reduced pressure.

(4) A step of obtaining a solidified composite microphone oral forceps preparation by decantation and / or centrifugation.

The method of the present invention can be applied to a method wherein the pesticidal active ingredient is a cyclohexanedione herbicide or an azole fungicide; particularly, cyclohexandione herbicide is setoxydim; and azole is a triflumizole. It can be suitably applied to In the method of the present invention, a biodegradable polymer such as polyepsilon force prolactam, polylactic acid, or a copolymer of polylactic acid and glycolic acid may be used as the film-forming polymer. As a solvent incompatible with water, for example, acetic acid Use ethyl. BEST MODE FOR CARRYING OUT THE INVENTION

The pesticidal active ingredient which can be used in the present invention is a solid pesticide having a high solubility in a non-polar solvent or a pesticide which is liquid at ordinary temperature and which is hardly soluble in water, preferably having a solubility in water of 10,000 ppm or less. There is no particular limitation, and two or more kinds may be used in combination. For example, azole fungicides such as triflum izole, and xanthone dichloride such as setoxy dim There are herbicides, etc., and it is also possible to use one kind or a mixture of two or more kinds.

Examples of the water-insoluble solvent used in the present invention include hexane, chloroform, dichloromethane, dichloroethane, isooctane, octane, nonane, ethynole acetate, and tonolen, and one or more of these are used. They can be used in combination. The film-forming polymer used in the present invention is a substance encapsulating the pesticidal active ingredient, and a styrene-divinylbenzene copolymer, polyepsilon-based prolatatam, polylactic acid, a copolymer of polylactic acid and glycolic acid, and a molecular weight and a structure. There is no particular limitation, and these may be used alone or in combination of two or more. The high oil-absorbing ability, inorganic substance or organic substance that can be used in the present invention is not particularly limited as long as it can be impregnated with a liquid pesticidal active ingredient. Examples of inorganic substances include silicon dioxide, bentonite, activated carbon, and silica gel. Examples include starch, cell π-source, and the like, and one or a mixture of two or more of these may be used.

The emulsifying and dispersing agent for the solvent that can be used in the present invention is not particularly limited as long as the solvent in which the agricultural chemical active ingredient and the film-forming polymer are dissolved can be emulsified and dispersed, and is added to a water-insoluble solvent or water. Can be. Tween surfactants such as tri- or distyryl ether added with polyoxyethylene, alcohol ether added with boroxoxyethylene, sorbitan oleate added with polyoxyethylene, and sorbitan oleate Spun surfactants such as ethate, sodium alkylnaphthalenesulfonate, sodium lauryl sulfate, sodium dodecyl sulfate, sodium V-guanine sulfonate, formaldehyde condensate of sodium alkylnaphthalenesulfonate, formaldehyde condensate of sodium phenolsulfonate, Polyglycenol condensed ricino such as copolymers of isobutylene-maleic anhydride and sodium polycarboxylate, sodium alkylnaphthalenesulfonate and sodium alkylbenzenesulfonate Organic substances such as phosphates, monola decaglycerin phosphate, gelatin, gum arabic, casein, dextrin, pectin, sodium anoregate, methylcenorelose, etinoresenorelose, polybutyl alcohol, and polybutylpyrrolidone Inorganic substances such as calcium phosphate may be mentioned, and one kind or a mixture of two or more kinds can be used.

In addition, in the present invention, in order to reduce foaming during the production of microcapsule preparations, a silicon-based surfactant, a sodium salt or a calcium salt or a mixture of higher fatty acids, an acetylene-based surfactant, or the like is added. You can also.

The amount of each component used in the production of the microcapsule preparation of the present invention varies depending on the kind of the pesticidal active ingredient. Usually, the amount of the pesticidal active ingredient is 0.01 to 60% by weight based on the final preparation amount. , preferably 0. 0 1-4 0% by weight, 0 the film-forming polymers for enveloping the agrochemical active ingredient. 0 0 5-8 0 weight ^_0/0, preferably 0. 0 0 5-5 0% by weight, The solvent for dissolving the pesticidal active ingredient and the film-forming polymer is 0.05 to 80% by weight, preferably 0.01 to 50% by weight, and an inorganic or organic substance having oil absorbing ability. 0 to 60% by weight, preferably 0 to 40% by weight, emulsifying / dispersing surfactant is 0 to 30% by weight, preferably 0 to 20% by weight, and defoamer is 0 to 10%. %, Preferably 0 to 5% by weight.

In implementing the present invention, (1) one or more pesticidal active ingredients and one or more of stylenedivinylbenzene copolymer, polyepsilon-based prolactone, polylactic acid, and a copolymer of polylactic acid and dalicholic acid A mixture of two or more kinds of film-forming polymers is dissolved in a solvent that is incompatible with water, and if necessary, impregnated with an oil-absorbing inorganic or organic substance (first step), (2) Agrochemical active ingredient Emulsify and disperse the solvent in which the polymer and the polymer are dissolved, or the impregnated material thereof in water using a homomixer or homogenizer as fine particles (second step), emulsify in the solution and heat the solvent in the emulsified particles dispersed. · Evaporate under reduced pressure to finely crystallize the polymer incorporating the pesticide active ingredient (3rd step) to produce a suspending agent. Next, (4) water is removed from the suspension by decantation or centrifugation (fourth step) to produce a microcapsule preparation. Example

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1

5 g of sethoxydim, 20 g of polyepsilon power prolatatam, and 1 g of polyglycerinole condensed ricinoleate are dissolved in 100 g of ethyl acetate to produce an organic phase. Next, an aqueous phase is produced by dissolving 4 g of polyvinyl alcohol and 1 g of deglycolic acid monolaurate in 500 g of water. The organic phase was added to the aqueous phase, and the mixture was emulsified for 5 minutes with a homogenizer (liquid temperature: 40 ° C, homogenizer rotation speed: 500 rpm), and the homogenizer rotation speed was set to 500 rp, at 40 ° C and 700 mmH. The ethyl acetate is completely evaporated by drying under reduced pressure for 3 hours with g, and encapsulation of sethoxydim with polyepsilon force prolactam. From the suspension, only the solid component was taken out by decantation to produce a microphone-mouth capsule preparation having a sethoxydim content of about 20%.

The composition of this micro force capsule is 5 g of sethoxydim, 20 g of polylactic acid, It is 1 g of deglycerol dephosphoric acid and the content of sethoxydim is about 20%. Example 2

Dissolve 3 g of triflumizole, 20 g of polyepsilon caprolactam and 1 g of polyglyceryl condensed ricinoleate in 74 g of ethyl acetate to produce an organic phase. Next, an aqueous phase is prepared by dissolving 4 g of polybutyl alcohol and 1 g of deglycolic acid monolaurate in 500 g of water. Add the organic phase to the aqueous phase, emulsify with a homogenizer for 5 minutes (liquid temperature 40 ° C, homogenizer rotation speed 500 rpm), set the homogenizer rotation speed to 5000 rpm, and dry under reduced pressure at 40 ° C and 700 mmHg for 5 hours. Then, the ethyl acetate is completely evaporated, and the triflumizole is encapsulated in polyepsilon force prolatam. From the suspension, only the solid component was taken out by decantation to produce a microforce capsule having a triflumizole content of about 12%. The composition of this micro force capsule is 3 g of triflumizole, 20 g of polyepsin mouth caprolatum, 1 g of polyglyceryl condensed ricinoleate, and the content of triflumizole is about 12%.

Example 3

Dissolve 10 g of triflumizole, 40 g of polyepsilon caprolatatam and 1 g of polyglyceryl condensed ricinoleate in 150 g of ethyl acetate to produce an organic phase. Next, 4 g of Polybiol alcohol and 1 g of decaglycerin monolaurate are dissolved in 500 g of water to produce an aqueous phase. Emulsified for 5 minutes in a homogenizer organic phase was added to the aqueous phase (solution temperature 40 ° C, homogenizer speed ⁵ 00 rpm), homogenizer The scratch rotational speed in the 5000 r pm 40 ° C, 700 mmH g for 5 hours under reduced pressure Drying completely evaporates the ethyl acetate and encapsulates the trifmin with polyepsilon force prolactam. Only the solid component was removed from this suspension by decantation to produce a micro-forced capsule having a trifmin content of about 20%.

The composition of this microforce capsule is 10 g of triflumizole, 40 g of polyepsiloncaprolactam, and 1 g of polyglyceryl-condensed ricinoleate, and the content of triflumizole is about 20%.

Example 4

Triflumizole 10 g, polylactic acid 20 g, POE Tristyryl FLA Dissolve in 3 g of ter and 200 g of dichloroethane to produce an organic phase. Next, 4 g of polyvinyl alcohol and 1 g of deglycolic acid monolaurate are dissolved in 500 g of water to produce an aqueous phase. The organic phase was added to the aqueous phase, and the mixture was emulsified with a homogenizer for 5 minutes (liquid temperature: 40 ° C, homogenizer rotation speed: 500 rpm), and the homogenizer rotation speed was set to 500 rpm to 40 ° C, 700 mmH. The dichloroethane is completely evaporated by drying under reduced pressure for 3 hours at g, and triflumizole is encapsulated with polylactic acid. From the suspension, only the solid component was removed by decantation to produce a microforce capsule having a triflumizole content of about 30%.

The composition of this micro force capsule is 10 g of triflumizole, 20 g of polylactic acid, 3 g of POE tristyrylphenyl ether, and the triflumizole content is about 30%.

Comparative Example 1

5 g of sethoxydim, 20 g of polyepsilon caprolactam and 1 g of polyglyceryl-condensed ricinoleate are dissolved in 100 g of ethyl acetate to produce an organic phase. Next, 4 g of polyvinyl alcohol and 1 g of deglycolic acid monolaurate are dissolved in 500 g of water to produce an aqueous phase. The organic phase was added to the aqueous phase, and the mixture was emulsified with a homogenizer for 5 minutes (liquid temperature: 40 ° C, homogenizer rotation speed: 500 rpm), and the resulting suspension was spray-dried (Okawara Kakoki Co., Ltd.). (Type 8) was spray-dried at a drying temperature of 10 ° C to produce a solid preparation in which sethoxydim was encapsulated with polypsilon power prolatatam.

The composition of this micro force capsule is 5 g of sethoxydim, 20 g of polylactic acid, and 1 g of deglycerol monophosphate, resulting in a cetoxydim content of about 20%. Comparative Example 2

Dissolve 3 g of Trifreno Mizonore, 20 g of Polypsilon Proprotatam and 1 g of polyglyceryl condensed ricinoleate in 74 g of ethyl acetate to produce an organic phase. Next, an aqueous phase is produced by dissolving 4 g of polybutyl alcohol and 1 g of deglycolic acid monolaurate in 500 g of water. The organic phase was added to the aqueous phase, and the mixture was emulsified with a homogenizer for 5 minutes (liquid temperature: 40 ° C, homogenizer rotation speed: 500 rpm). The obtained suspension was spray-dried (Okawara Kakoki Co., Ltd. Drying temperature using mold) It was spray-dried at a temperature of 100 ° C. to produce a solid preparation in which triflumizole was made into a forcepsel with polyepsilon force prolactam.

The composition of the Mike mouth capsule preparation is 3 g of triflumizole, 20 g of polypsin mouth prolactam, 1 g of polyglyceryl condensed ricinoleate, and the content of triflumizole is about 12%.

Comparative Example 3

Mix 3 g of triflumizole, 60 g of paraffin wax, 30 g of carnauba wax, 1 g of silicon oxide, 7 g of talc and 9 g of polybutyl alcohol, knead the mixture at a temperature of 100 ° C where the wax melts, and form a clay. I do. The clay was granulated using an extrusion granulator (PV-5) (extrusion diameter: 0.7 mm) and solidified by air-cooling to produce a solid preparation in which triflmizole was wrapped with a Pex component.

Comparative Example 4

Dissolve 2 g of trifinolemizole, 0.5 g of styrene-maleic anhydride copolymer & salt in a solvent SAS-296 g, and protect it with 2.5 g of urea in 86.5 g of water. (Urea _2.5 + + water 84), adjust the pH to 3 with 10% aqueous citric acid, and emulsify with a homogenizer at 5000 rpm for 10 minutes. To this emulsion, add 6.8 g of 37% formalin water (2.5 g of formalin), raise the solution temperature to 70 to 75 ° C, and homogenizer at 10,000 rpm for 2 hours. At the surface of the emulsified particles. After the reaction, lower the liquid temperature to 40 ° C and adjust the pH to 7.5 with 28% ammonia water. From the suspension, only the solid component was taken out by decantation to produce a microphone mouth capsule preparation having a triflumizole content of about 13%. Test Example 1: Measurement of Yield of Micro Force Pexel Formulation

The yield was calculated from the charged amount (A) when 100% was recovered in the production of microcapsule preparations and the amount (B) recovered in actual production.

Yield (%) = B / AX 100

Test Example 2: Measurement of pesticide active ingredient content in micro force capsule

Then, 10 g of the prepared micro force-pressed solid preparation is immersed in 100 ml of methanol, and sethoxydim or trifnoremizole is ultrasonically extracted from the micro force-pressel for 30 minutes. Analyze extracted sethoxydim or triflumizole by HP LC Then, the content of sethoxydim or triflumizonole in the microcapsules was calculated. Test example 3: Measurement of the micro force force

10 g of the manufactured solid preparation of microcapsules is immersed in 100 ml of hexane and gently stirred with a spatula for about 30 seconds. After stirring, the mixture is allowed to stand for 5 minutes. After confirming that the microcapsules have settled, the supernatant is analyzed by HPLC, and the amount of the drug substance dissolved in hexane is measured to calculate the microencapsulation rate.

Microencapsulation rate (%) =

(Amount of drug substance in microcapsule preparation-drug substance dissolved in hexane)

Active ingredient in Z micro force capsules X 100 Test example 4: Measurement of drug dilution properties

A mixture of ligninsulfonic acid Na10 g, alkylnaphthalenesulfonic acid Na salt formaldehyde condensate 5 g, alkylnaphthalenesulfonic acid Na2 g2 and clay 73 g was milled with a jet mill to a powder diameter of about 7 microns. Manufactures wettable powder base. A wettable powder is manufactured by mixing 10 g of the microencapsulated solid preparations produced in Examples and Comparative Examples with 90 g of a wettable powder base in a mortar. This wettable powder was diluted 100 fold with tap water and diluted physical properties (measurement items; self-dispersibility, initial dispersibility, suspension stability, foaming property) were measured.

• Self-dispersibility; 0.25 g of wettable powder in 200 ml of tap water (250 ml of measuring cylinder)

The state of dispersion of the drug when dropped. Dispersed into a cloud ◎> 〇> △> X No dispersion at all

• Initial dispersibility; the graduated cylinder is inverted 30 seconds after the drug is released, and the drug is completely dispersed.

Number of inversions required for

• Suspension stability: The amount of sedimentation (ml) after 30 inversions of the measuring cylinder.

• Foamability: Foam height (m 1) 30 minutes after inverting 30 graduated cylinders. The results of Test Examples 1 to 3 are shown in Tables 1 and 2 below. Example 1 Comparative Example 1

Recovery rate (%) 100 39

Micro-casselling rate (%) 90

Self-dispersibility ◎ O

Initial dispersibility (pcs) 1 1

Foamability (ml) 4 3

Suspension stability (m 1)

1 h r 0.01 0.35

2 h r 0.06 0.56

24 h r 0.20 0.77

Table 2

Industrial potential

ADVANTAGE OF THE INVENTION According to this invention, the concentration of the pesticide active ingredient in a microcapsule is high, and the microencapsulated preparation of the pesticide with good diluent properties can be efficiently produced.

Claims

The scope of the claims

1. A method for producing a micro force capsule comprising the following steps:

(1) One or more kinds of film formation of one or more pesticidal active ingredients and styrene-di-bulbenzene copolymer, polypsilon power prolatatam, polylactic acid, copolymer of polylactic acid and glycolic acid A step of dissolving the mixture with the polymer in a water-incompatible solvent that can dissolve them.

(2) A step of emulsifying and dispersing the solution obtained in the previous step in water using a homomixer or a homogenizer.

(3) A step in which the solvent in the emulsified and dispersed solution is heated and evaporated under reduced pressure to crystallize the pesticidally active component and the polymer.

(4) A step of obtaining a solidified composite microphone oral capsule formulation by decantation and / or centrifugation.

2. The production method according to 1, wherein in the step (2), the production is carried out by adding an emulsifying / dispersing agent to a solvent.

3. The production method according to claim 1, wherein the pesticidal active ingredient is a cyclohexanedione herbicide.

4. The method according to claim 3, wherein the cyclohexanedione herbicide is sethoxydim.

5. The production method according to claim 1, wherein the pesticidal active ingredient is an azole bactericide.

6. The production method according to claim 5, wherein the azole bactericide is triflumizole.

7. A film-forming polymer comprising: polypsilon power prolactam, polylactic acid, or a copolymer of polylactic acid and glycolic acid; and ethyl acetate or dichloroethane as a water-insoluble solvent. The method according to any one of claims 1 to 6.

8. A composite microphone-mouth capsule preparation produced by the method according to any one of claims 1 to 7.