KR900006515B1 - Microen capsulated agent of ethoprophos - Google Patents

Abstract

Microencapsulated ethoprophos (I; O-ethyl-S,S- dipropylphosphoridithioate) comprises (1) a core material, made by dissolving (I) in a vegetable oil able to dissolve over 20 wt.% (I) at 25 deg.C; and (2) a membrane wall, consisting of a polycondensate derived from a resin prepolymer made from HCHO and at least one of urea and melamine. Specifically the rate of (I) release is 0.5-10 wt.% when the microcapsules (equiv. to 30 mg (I)) is stired for 1 hr at 20 deg.C in 700 ml water.

Description

Etoprofoss Microcapsules

The present invention has low toxicity, almost no irritating odor, and possesses almost complete nematode action of ethoprophos and slowly releases etopropos (0-ethyl S, S-dipropylphosphoro). Dithioate) microencapsulated agent. More specifically, the present invention provides a polycondensation of a core material obtained by dissolving 20% by weight or more of etoprofos at 25 ° C, and at least one material selected from urea and melamine and a resin prepolymer that is formaldehyde. A microcapsule of etoprofos including a microencapsulated wall of water (waIl membrane)

Although etoprofos has high nematodeness and has been put to practical use in many countries, its use is greatly limited due to its high toxicity and strong irritant odor, which brings great difficulties in its practical use. At present, some countries (eg Japan) have not been put to practical use due to the strong toxicity of erotic profoss. In order to reduce the toxicity and odor of etoproforce, various designs such as granulation of etoproforce have been made, but have not been brought to practical use.

On the other hand, U.S. Patent No. 4,557,755 provides an idea of slowly releasing the active ingredient to the outside to prevent the adverse effects on the living organisms other than harmful organisms, which are pesticides as the active ingredient of the pest control and to extend the effect.

However, the etoprofoss used in the present invention is a nematicide, and the properties of the etoprofoss to kill the seabeds living in the soil can not be similar to the properties of conventional pesticides such as insecticides, herbicides, fungicides, but quite different. Can be.

Meanwhile, US Patent No. 4,557,755 describes a technique for preparing microcapsules containing pesticides as a core substance in a technology-intensive form without using a solvent. If the technique is applied to the case of etoprofoss, the difference in properties is great. Because of this, it is practically impossible to microencapsulate etoproforce. U.S. Patent No. 4,557,755 mentions very briefly about the use of solvents, but does not describe any effects of using solvents or the difficult choice of suitable solvents.

Etoprofoss is an oily liquid having a relatively high solubility in water, and when preparing an emulsion of etoprofos with water, the emulsion state is extremely unstable and easily broken and separated into an etoprophos layer and an aqueous layer. Moreover, the interface between etoprofoss and droplets of water is unstable and does not represent a clean boundary. That is, formation of coacervates at the interface is very difficult.

In addition, the rate of release of etoproforce from the capsule, which is an important property of the product of the present invention (hereinafter referred to as "the product"), such as sustained release and low toxicity, cannot be controlled by simply adjusting the thickness and composition of the capsule membrane.

In order to obtain microcapsules of etoprophos which have the action of the stratum lamina of etoprofoss, have low toxic and irritating odor and have a sustained release rate of etoprofos, the results of the present inventors' study have selected a specific solvent for etoprofoss. By discovering the fact that the above defects can be solved, the present inventors have completed the present invention.

It is an object of the present invention to provide a microcapsule of etoprofos with a nematicidal action and low toxicity and irritant odor.

Another object of the present invention is a core material, a solution of etopropos and a specific solvent that dissolves more than 20% by weight of ethprofos at 25 ℃, and as a membrane material, at least one substance selected from urea and melamine and formaldehyde The present invention provides a microcapsule of etoproforce comprising a polycondensate of a resin prepolymer.

Still another object of the present invention is to show that when the microcapsules corresponding to 30 mg of etoprophos are mixed in 700 ml of water at 20 ° C. for 1 hour, the etoprofos micro exhibits a release ratio of 0.5 to 10 wt% of etoprophos. To provide a capsule.

Another object of the present invention is to provide an etoprophos having a polycondensate of a resin prepolymer prepared from formaldehyde and at least one compound selected from urea or melamine as a wall of microcapsules with a water-soluble cationic urea resin in the presence of an anionic surfactant. It is to provide a microcapsules.

The microencapsulation of etoproforce according to the present invention is the core material, after the droplets of a solution in which etopropos is dissolved in a solvent are dispersed in an aqueous solution of a prepolymer of urea and formaldehyde (hereinafter referred to as "UF prepolymer"). By precondensation of the prepolymer on the interface of the droplets.

The solvent used in the present invention should have the following properties: (1) 20 wt% or more of etoprophos is dissolved; (2) The droplets of the solution dissolving etoprofos have a stable interface when dispersed in water. 3) Does not affect the action of nematode nematodes (4) It is not toxic to mammals and does not cause environmental pollution. (5) It does not damage useful plants and has no residual toxicity. (6) Boiling point (7) dissolves water to some extent, for example tens to hundreds of ppm

While the need for properties (1) to (6) is obvious, a more detailed description of property (7) will help to understand the object of the present invention. In other words. Since the membrane of the microgrocapsule dispersed in water is swollen by water and a passage is formed in the membrane which is sized to pass the core material, the hydrated solvent penetrates the membrane swollen by water more easily than the solvent which is completely hydrophobic, Edoprophos may be adequately released from the microgrocapsules. However, when the content of water in the solvent is too large, etoprophos can be released rapidly. However, when the content of water in the solvent is too large, etoprophos is rapidly released, it is necessary to have the content of water in the solvent within a specific range.

Etoprofoss microcapsules having a suitable release rate can be obtained by dissolving etoprofos in a solvent having the above seven properties to prepare a core substance, i.e., selecting the release rate of etoprofos from the microcapsules. To this end, the thickness aging and composition of the membrane material is important, but above all, it is necessary to introduce a new concept of selecting a suitable solvent for etoproforce.

Suitable solvents for this purpose include vegetable oils such as soybean oil, castor oil, olive oil, linseed oil and corn oil.

The mixed weight ratio of such vegetable oil and etoprofos is 7: 3 to 2: 8, preferably 5: 5 to 3: 7.

By mixing etoprofos with the vegetable oil and dissolving it in the vegetable oil, the etoprophos odor can be attenuated, and the membrane-forming properties and emulsification of the etoprophos can be improved to encapsulate the etoprophos.

Microencapsulation of etopropos according to the present invention can be carried out by forming a membrane prepared by polycondensation of an amino resin prepolymer along the surface of droplets of vegetable oil and etoprofos solution as a key substance.

Examples of the amino resin prepolymers include the following, that is, the resin prepolymers used in the present invention are prepolymers of urea-formaldehyde resins and prepolymers of melamine-formaldehyde resins (hereinafter referred to as "MF prepolymers"). And prepolymers of belamine-urea-formaldehyde resins (hereinafter referred to as " MUF prepolymers ").

MF prepolymer means monomethine methyl from melamine to hexamethylol melamine; mixture of melamine and formaldehyde; methyl methylation with different degrees of methylation; mixture of melamine or mixture of methylol melamine and melamine; It may be a transparent colloidal solution obtained by treating oligomer obtained by the reaction between melamine and formaldehyde, that is, methylol melamine having a polymerization degree of 2 to 10 with hydrochloric acid.

These MF prepolymers can be easily formed by heating the mixture of melamine and formaldehyde in an alkaline state, and the resulting aqueous reaction mixture itself can be encapsulated.

UF prepolymer means a mixture of formaldehyde and methylolated urea, a mixture of methylolated ureas with different degrees of methylolation, or a mixture of methyl urea and urea from monomethyl to urea to tetramethyl to urea; The polymer may be an oligomer obtained by the reaction between urea and formaldehyde, i.e. a transparent colloidal solution having hydrophilic groups with a degree of polymerization of 2 to 5

In contrast, MUF prepolymers obtained by heating formaldehyde, melamine and urea in an alkaline state can be used alone or in combination with MF prepolymers or UF prepolymers for the purposes of the present invention.

Microencapsulation according to the invention is described in detail with reference to the method of using vegetable oil as solvent and UF, AIF or AIUF prepolymer as membrane material as follows.

A solution of vegetable oil and etopromos was added to a mixed aqueous solution containing a water-soluble cationic urea resin and an anionic surfactant, and the pH of the mixture thus prepared was adjusted to 4 to 5, followed by the use of a suitable number such as ultrasonic wave. The solution is dispersed in the system to form an emulsion containing an equalizer, an arrogant, droplets of the etoprophos solution at a suitable size, eg 1-6 μm in diameter.

To the emulsified aqueous solution containing a solution of vegetable oil and etoprophos, a resin prepolymer as a membrane material is added in a weight ratio of 9: 1 to 1: 1. The prepolymer may be added one or several times before or during emulsification of the mixed aqueous solution. The emulsion is emulsified at pH 4-5 and at a temperature of 20-60 ° C., preferably at 30-50 ° C.

After reacting the emulsion to which the prepolymer has been added (polycondensation) for 14 to 25 hours while slowly stirring, the pH of the emulsion is adjusted to 2.5 to 4.0, and the emulsion is then heated at 30 to 60 캜 for 40 to 50 hours. By reaction to complete microencapsulation.

The water-soluble cationic urea resin used in the microencapsulation is a material prepared by introducing a cation regulator into the urea-formaldehyde resin, for example, tetraethylene pentamine, diaminoethane, dicyandiamide, diethylaminoethanol, sphere Aniurea or similar substances are easily obtained by adding the prepolymers of urea and formaldehyde and then subjecting the mixture to polycondensation by known methods. The weight ratio of the water-soluble cationic urea resin to the prepolymer of urea and formaldehyde is preferably 1.0.01 to 1: 2.0.

The anionic surfactants include fatty acid salts, sulfate esters of higher alcohols and salts of alkylarylsulfonic acids, with sodium dodecylbenzenesulfonate being preferred.

In the microcapsule slurry according to the present invention, in order to further adjust the release property of the active ingredient etoprophos in the microcapsules, after adjusting the pH of the microcapsule slurry from 3.5 to 7, the dispersant described later is 0 5 The capsule-like membrane is aged by adding the slurry in an amount of 2 to 2% and then leaving the slurry in the state at 40 to 60 ° C. for 60 to 80 hours. The maturation time can be determined in consideration of the desired ratio of etoproforce to release from the microcapsules into water and the type of resin-prepolymer used to prepare the microcapsules. However, the aging of the capsule membrane proceeds slowly by leaving the slurry for a long time after the end of the encapsulation, but this method cannot be performed because it takes several months to obtain a capsule which can be used in practice.

As the dispersant used for the aging, salts of alkylarylsulfonic acids such as alkylbenzenesulfonic acid and alkylnaphthalenesulfonic acid or formaldehyde and condensates thereof are preferably used.

As mentioned above, the amount of etoprophore released from the microcap into water is equivalent to 30mg of etoprofos in 700m1 of water, which is released into water when the microcapsule is shaken for 1 hour. The amount of force is shown, and the amount of etoprophos released in water is represented by white powder. In other words, the ratio of etopropos to water from the microcapsules indicates the degree of release of etoprofos to water, although the ratio depends on the maturation and thickness of the microcapsules. Is mainly influenced by the prepolymer of the resin used to prepare the membrane of the microcapsules

In this regard, UF prepolymers are useful for making compact membranes. On the other hand, even if the MF prepolymer rapidly forms a membrane and microencapsulation by the MF prepolymer is easily performed, the compactness of the thus formed membrane is low, and thus a microcapsule having a large release ratio of etoprofos to water can be obtained.

Although the MF prepolymer or the UF prepolymer can be used alone as the membrane material for the present invention, it is preferable to use a mixture of the two prepolymers in a specific range of mixing ratios. The release of etoproforce into the water through the wall is easy and vice versa. Thus, when using a mixture of MF prepolymers and MF prepolymers (weight ratio MF: UF = 4: 1 to 1: 1), the film thickness of the microcapsules can be controlled over a wider range while at the same time The release rate can be more easily controlled than when using the preprepolymer alone.

As a result, when the MF prepolymer is used together with the UF prepolymer within the above ratio, it is possible to obtain a microcapsule which retains nematode action for several months and has little skin toxicity of etoprofos.

The microcapsules according to the present invention are preferably treated into aqueous slurry after controlling the concentration of etoprophos in the slurry without filtering the slurry, and before the aging of the microcapsule membrane carried out by adding a dispersant to the slurry. It is desirable to obtain the desired concentration of etoprofoss.

Since the concentration of etopropos in the microcapsules can be changed, it is inevitable to change the concentration of the microcapsules in the slurry in order to maintain the concentration of etopropos in the slurry within the desired range. It is preferable to adjust the concentration of the microcapsules in the range of 20 to 50% by weight.

Furthermore, after aging the microcapsule wall, for example, by filtration, the microcapsules of etoprofos are separated from the slurry and converted into a powder form, and then the powdered substance obtained above, such as a powder product or a wettable powder product, is prepared. Can be used.

As described above, in the case of processing the powdered substance into a drug, an adjuvant such as a granule aid, an extender, a surfactant, etc. may be appropriately used. Particularly, in the case of manufacturing a granule drug, granulation is preferably performed. Microcapsules are contained in the drug in an amount of 5 to 30% by weight.

The invention and its effects are described in detail with reference to the following examples, comparative examples and test examples.

Example 1

Example 1 shows a method for preparing microcapsules according to the invention.

1-1: Preparation of Resin Prepolymer as Membrane Material

63 g (0.5 mol) of melamine was added to 171.5% (2.0 mol) of an appropriate 35% by weight aqueous formaldehyde solution with a pH of 9.0 with a 2% aqueous sodium hydroxide solution and the resulting mixture was reacted at 70 ° C. Immediately after the melamine was dissolved, 243.5 g of water was added to the reaction mixture, and the resulting mixture was stirred for 3 minutes to prepare an aqueous MF prepolymer solution.

Separately, the mixture formed by adding 150 g (2.5 moles) of urea to 386 g (4.5 moles) of 35 wt% formaldehyde aqueous solution having pH adjusted to 8.0 with triethanolamine was reacted at 70 ° C. for 1 hour to prepare an aqueous solution of UF prepolymer. did.

1-2 Microcapsulation

P 1500, 미쓰이-도아쓰사 제품),900g의 물,10% 트리에탄올아민 수용액 45g, 상기에서 제조했던 MF 예비중합체 수용액 450g 및 UF 예비중합체 수용액 450g을 혼합하여 혼합물을 제조하고, 형성된 혼합물의 pH를 25% 시트르산 수용액으로 4.2로 조절한 후 10%나트륨 알킬벤젠설포네이트 수용액(NEOPLEX

, KAO사 제조) 13.5g을 상기 혼합물에 첨가했다.120 g of water soluble cationic urea resin (URAMIN)

P 1500, manufactured by Mitsui-Toatsu), 900 g of water, 45 g of 10% aqueous triethanolamine solution, 450 g of MF prepolymer aqueous solution prepared above and 450 g of UF prepolymer aqueous solution were mixed to prepare a mixture, and the pH of the formed mixture was 25 10% sodium alkylbenzenesulfonate aqueous solution (NEOPLEX) after adjusting to 4.2 with aqueous citric acid solution

13.5 g of KAO Co., Ltd.) was added to the mixture.

900 g of a mixture consisting of 630 g of etoprofos (technical product with a purity of 96%) and 270 g of soybean oil were added to the mixture, and then the mixture formed with a homogenizer was emulsified so that the diameter of the emulsion droplets was 1.5 to 4 m. The emulsion formed was left at 50 ° C. with slow stirring. After 10 minutes and 3 hours of stirring, 1 liter of hot water at 50 ° C. was added to the emulsion. After 24 hours of stirring, the emulsion pH was adjusted to 2.8 with 25% aqueous citric acid solution and 48 hours after stirring, microencapsulation was completed.

1-3: Aging of the microcapsule membrane

N)를 첨가하고, 형성된 혼합물을 72시간 동안 50℃ 온도로 유지하면서 천천히 교반하여 숙성시켰다.The microcapsule slurry obtained by the microencapsulation was adjusted to pH 5.0 with an aqueous 28% ammonia solution, and the water portion was removed from the slurry to obtain an etoprofos content of 15% by weight and a slurry amount of 4000 g. 40 g of a dispersant (condensation product of alkylarylsulfonic acid and formalin, registered trademark of KAO Corporation (DEMOL) in the slurry thus adjusted

N) was added and the resulting mixture was aged by stirring slowly while maintaining the temperature at 50 ° C. for 72 hours.

A portion of the slurry thus prepared was filtered to obtain powdered microcapsules having an average diameter of 2.48 μm. The content of etoproforce in the microcapsules was 46.87 wt%.

Example 2

Microencapsulation of etoproforce was carried out in the same manner as in Example 1 except that 1350 g of MF prepolymer was used alone. The average diameter of the microcapsules thus obtained was 2.84 μm and the content of etoprofos was 46.14 wt%.

Example 3

Microencapsulation of etoproforce was carried out in the same manner as in Example 1 except that 675 g of UF prepolymer was used alone. The average diameter of the microcapsules thus obtained was 2.13 μm and the content of etoprofos was 46.19 wt%.

Example 4

Etoprophos was microencapsulated in the same manner as in Example 1 except that 630 g of etoprofos (technical product) and 900 g of 270 g of olive oil mixture were used. The average diameter of the microcapsules thus obtained was 2.94 µm and the content of etoprofos in the microcapsules was 46.36 wt%.

Example 5

Etoprofoss were encapsulated in the same manner as in Example 1 except that 630 g of etoprofos (technical product) and 270 g of castor oil mixture 900 g were used. The average diameter of the microcapsules thus obtained was 2.42 μm, and the content of etoprops in the slurry was 15.11 wt%.

The following Examples 6 to 10 illustrate the preparation of microencapsule of etoproforce according to the present invention.

Example 6

The slurry in Example 1 after the aging of the microcapsules was prepared with microcapsules of etoprofos without separating the microcapsules from the slurry. The concentration of microcapsules in the obtained slurry was 32.46 wt% and the concentration of etoprofos was 15.25 wt%.

Example 7

The suspension was obtained by mixing 120 g of a solid material (containing 26% by weight of etoprofos and 40% by weight of water with 250 g of an 8% polyvinyl alcohol aqueous solution) obtained by filtering the slurry of Example 1 after aging of the microcapsules. It was sprayed onto the surface of 900 g of granular product of 0.7 mm pumice to obtain 960 g of etoprofos microgrocapsules. The content of etoprofos in the product was 3.12% by weight.

Example 8

N)를 함유하는 습윤성 분말을 수득하였다 이렇게 수득한 습윤성 분말중 에토프로포스의 함량은 44.50중량%이여다700 g of the slurry obtained in Example 1 after aging of the microcapsules was dried by spray drying to disperse about 3% by weight of a dispersant (DEMOL

A wettable powder containing N) was obtained. The content of etoprophos in the wettable powder thus obtained was 44.50% by weight.

Example 9

In the same manner as in Example 6, the slurry product containing the microcapsules was obtained by treating the slurry obtained in Example 4 after the ripening of the microcapsules. The concentration of microcapsules in the obtained slurry was 32.62 wt% and the concentration of etoprofos was 15.17 wt%.

Example 10

In the same manner as in Example 6, the slurry product containing the microcapsules was obtained by treating the slurry obtained in Example 2 after the microcapsules had been aged. The concentration of microgrocapsules in the obtained slurry was 32.52% by weight and the concentration of etoprofos was 15.27% by weight.

The following Comparative Examples 1 to 5 illustrate the case where etoprofos (technical product) is used as a core material without using a solvent and when diisopropylnaphthalene or diethylphthalate is used as a solvent.

Comparative Example 1

Etoprofoss was microencapsulated in the same manner as in Example 1 except that only 900 g of etoprofos (technical product) was used, but a large amount of etoprofos that did not enter the microcapsules was suspended in the system as a free oil. Microencapsulation was not possible and the reaction did not continue.

Comparative Example 2

Etoprofos was microencapsulated in the same manner as in Example 1 except that 900 g of a mixture of 630 g of etoprofos (technical product) and 270 g of diisopropylnaphthalene was used.

The average diameter of the microcapsules thus obtained was 2.52 μm and the content of etoprofos was 46.76 wt%.

Comparative Example 3

Etoprofos was microencapsulated in the same manner as in Example 1 except that 900 g of a mixture of 630 g of etoprofos (technical product) and 270 g of diethylphthalate were used.

The microcapsules thus obtained had a Ping fungus diameter of 3.44 μm and the content of etoprofos was 47.01 wt%.

[Comparative Example 4]

In the same manner as in Example 4, the slurry obtained in Comparative Example 2 after the aging of the microgrocapsules was prepared using a microcapsule of etoprofoss. The concentration of microcapsules in the slurry thus obtained was 32.11 wt% and the concentration of etoprofos was 14.93 wt%.

[Comparative Example 5]

In the same manner as in Example 4, the slurry obtained in Comparative Example 3 in which the aging of microcapsules was sticky was prepared with the microcapsules of etoprofoss. The concentration of microcapsules in the slurry thus obtained was 32.14 wt% and the concentration of etoprofos was 15.03 wt%.

In the following, the functional effects of the etoprofos microcapsules were tested and the results are shown in Test Examples 1-5.

Comparative Example 6

925 g of granules were prepared by spraying and impregnating 35 g of etoprofos (technical product) on the surface of the granular product of pumice stone and then spraying 250 g of polyvinyl alcohol solution on the surface of the granular product of pumice stone. The content of etoprofos in the preparation was 3.3% by weight.

The test for functional effect was carried out with the product obtained in Comparative Example 6.

[Test Example 1]

Etoprofos microcapsules obtained in Examples 1 to 5 and Comparative Examples 2 to 3, respectively, in an amount corresponding to 300 mg of etoprophos relative to the rate of release of etoproforce into water, were placed in a 1 liter round bottom flask. 700 ml of water was added to the flask, and the plaque was shaken at 20 ° C. for the determined time. Then, the concentration of etoprophos in the water was measured at the determined time. Calculated according to the formula and the results are shown in Table 1.

TABLE 1

[Test Example 2]

In the microcapsules prepared in Examples 6 to 10 and Comparative Examples 4 to 6, the ratio of release of etoprophos to water was measured in the same manner as in Test Example 1, and the test was also performed on the product of Comparative Example 6. The test results are shown in percentage in Table 2.

TABLE 2

[Test Example 3]

The amount of each of the products obtained in Examples 6 to 8 and Comparative Example 6 corresponding to 8 mg of etoprofos was placed in a 50 ml capacity sample vessel, shaken the vessel five times and then left in a 40 ° C. warmer for a predetermined time. The vessel was removed from the warmer and shaken five times, and the contents of the vessel were filtered to obtain a filtrate. The concentration of etoprofos in the filtrate was measured to calculate the rate of ethoproposal release into water. The results are shown in Table 3. These data show the release rate by the method of leaving the sample agitated instead of shaking.

[Test Example 4]

This example shows the results of severe mammalian skin toxicity of the microcapsules obtained in Example 1 and the etoprofos microcapsules obtained in Examples 6-10 and Comparative Examples 4-6. Severe mammal skin toxicity was measured as follows.

Using ICR rats 7 weeks old as test animals, LD ₅₀ values were measured by testing each herd of five rats according to the toxicity test specified by the Minister of Agriculture, Fisheries and Fisheries (Notice NOSAN NO.4200). We show in 4

[Test Example 5]

This example shows the results of nematode control test and plant growth test carried out using the microcapsules obtained in Examples 6 to 10 and Comparative Examples 4 to 6 in the following manner.

[Test Methods]

Each sample of the microcapsules is mixed with contaminated soil in a line layer (Meloidogyne incognita acrita) so that the dosage ratio is 250 g / 10 ar, 500 g / 10 ar and 1000 g / 10 ar, respectively. Soils were placed in 3 plastic pots (p (} t) at 1 kg / pot, followed by sowing of 15 tomato seeds in the soil of each pot 7 days after mixing, simultaneously with sowing and 36 days after tomato plant growth. 20 grams of soil were taken, the strata were separated from the soil by the Bernan method, and the number was counted.

The soil contaminated soil used in this test was prepared by mixing a small amount of soil contaminated with normal test soil for plant growth and growing sweet potatoes to propagate the hull, and as a comparative soil, normal test soil for plant growth control. Was used.

Furthermore, 36 days after soil treatment with microcapsules, all tomato simulated root-node indices in the photo were examined according to the following criteria and formulas:

Where the rating is:

The height and original weight of the leaves relative to the hair were measured and the results are shown in Table 5.

TABLE 3

TABLE 4

TABLE 5

Note: * 1) N = 30; * 2) New weight

As shown in Table 5, the microcapsules according to the present invention are the same as or better than those of the microgrocapsules prepared in the comparative examples in terms of nematode control effect and plant growth properties, in particular, the slurry does not exhibit any phytotoxicity. Significant nematode action was observed even at utilization rate of 250g / 10.

As described above, the microcapsules of etoprofos according to the present invention exhibit the same or better effect as granules of etoprofos prepared without using microencapsulation on the action surface of the aerobic layer. the skin toxicity LD ₅₀ toxicity of etoposide Pro force itself of 45mg / kg as opposed to the microcapsules themselves is skin toxicity of the microcapsules of a 2,600m9 / kg, slurry-type ETO Pro force calculated as etoposide Pro phosphine agent is etoposide Pro 3,200 mg / kg calculated as force. That is, the toxicity of the microencapsulated etoproforce (technical product) according to the present invention was greatly reduced.

Particularly in the form of a slurry, there is a practical advantage in that microcapsules can be used without separating the microcapsules from the slurry. Moreover, granular products can be prepared by adding the granules to the slurry and, if necessary, can be made into any form of product after obtaining the powdered material by separating the microcapsules from the slurry.

Moreover, the inherent strong odor of Etprofoss is hardly exhibited by microcanvas, and there is no problem of dealing with the microcapsules and the greatly reduced skin toxicity of the microcapsules according to the present invention.

Claims (15)

Wall film of a polycondensate prepared from a core material prepared by dissolving etoprofos in vegetable oil dissolving at least 20% by weight of etoproph at 25 ° C, and at least one compound selected from urea mit melamine and a resin prepolymer made of formaldehyde. Etoprops microcapsules consisting of. The microencapsule of etoprofos according to claim 1, wherein the release rate of etoprofos in water is 0.5 to 10% by weight when the microcapsules corresponding to 30 mg of etoprofos in 700 ml of water are shaken at 20 ° C for 1 hour. The microcapsule of etoprofos according to claim 1, wherein the wall film of the polycondensate is prepared from a water-soluble cationic urea resin and a resin prepolymer in the presence of an anionic surfactant. The microcapsule of etoprops according to claim 1, wherein the mixed weight ratio of etopropos to vegetable oil is 7: 3 to 2: 8, The microcapsule of etoprofos according to claim 1, wherein the weight ratio of the core material to the wall membrane is from 9: 1 to 1: 1. The microcapsule of etoprofos according to claim 1, wherein the wall membrane is a prepolymer of urea and formaldehyde, a prepolymer of melamine and formaldehyde or a mixture of two prepolymers. The microcapsule of etoprofos according to claim 6, wherein the wall membrane comprises 1 part by weight of prepolymer of melamine and formaldehyde and 1 to 4 parts by weight of polycondensation rule of urea and formaldehyde. The microgrosses of etoprofoss according to claim 1, which are oils selected from vegetable oil, castor oil, olive oil, linseed oil, rapeseed oil, corn oil and mixtures thereof. 7. The micro-encapsulation agent of etoprofos according to claim 6, wherein the wall film of the polycondensation rule is prepared from a water-soluble cationic urea resin and the resin prepolymer in the presence of an anionic surfactant. The method according to claim 1, wherein the wall membrane of the polycondensate is formed from a mixture of 1 part by weight of a water-soluble cation urea resin, melamine-formaldehyde prepolymer and 1 to 4 parts by weight of urea-formaldehyde prepolymer in the presence of an anionic surfactant. Microcapsules. 10. The microcapsule of etoprofos according to claim 9, wherein the weight ratio of the water-soluble cationic urinary resin to the resin prepolymer is 0.01: 1 to 2.0: 1. The microencapsulation agent of etoprofos according to claim 9, wherein the anionic surfactant is a salt of a fatty acid, a sulfate ester of a higher alcohol or a salt of an alkylarylsulfonic acid. The microcapsules of etoprofos according to claim 1, which contain 20 to 50% by weight of microcancellules and 0.5 to 2% by weight of dispersant and have a pH of 3.5 to 7 in an aqueous slurry state. According to claim 1, Etoprofoss microcapsules in powder form containing 80 to 97% by weight of the microcapsules and 20 to 3% by weight of the surfactant. The microcapsule of etpropos according to claim 1, which is in the form of granules containing 5 to 30% by weight of microcapsules.