JPH07103003B2 - Agro-horticultural wettable powder - Google Patents

Description

TECHNICAL FIELD The present invention relates to an agricultural and horticultural wettable powder. For more details,
A wettable powder for agricultural and horticultural use, which comprises a compound of formula (I) having an average particle diameter of 5 μm or less as an active ingredient and prepared so that the surface tension of a spray liquid after dilution is 50 dyn / cm or more. .

(Prior Art) Agro-horticultural chemicals are used for the convenience of use.
It has been formulated into powders, emulsions, granules, wettable powders, aqueous solutions, oils, water solutions and the like. Recently, from the viewpoint of safety of users and prevention of pollution, a flowable agent that does not contain a lot of harmful organic solvents (also called a sol agent; hereinafter abbreviated as FL agent) and a dry flowable agent with little dusting (or granular water). New drug types such as wa-drugs (hereinafter abbreviated as DF agents) have been developed. FL
There are agents that use water as the continuous phase and agents that use an organic solvent. The dispersed phase of each is solid (suspension type) and liquid (emulsion type).
There is. In addition, the DF agent is a wettable powder which is made into a granular form by an appropriate device, and when diluted in water, it becomes a uniform suspension as if the wettable powder was diluted. These FL agents and DF agents are also classified as a wettable powder in a broad sense.

Generally, an emulsion uses a surfactant having a relatively high surface tension lowering ability because it is necessary to emulsify the active ingredient and the organic solvent in water. For this reason, when the emulsion is diluted with water, the surface tension of the diluted solution is usually as low as about 40 dyn / cm.

On the other hand, in order to enhance the biological effect, the wettable powder is generally mixed with a surfactant having a strong surface tension lowering ability, or a spreading agent is added to the spray liquid to intentionally prepare the spray liquid. Surface tension 40
It is often used after reducing it to about dyn / cm or less.

(Problems to be Solved by the Invention) The compound of formula (I) is described in JP-A-62-67,
It is known to have insecticidal and acaricidal activity. When this compound is made into the usual dosage form described above and actually treated in the field,
Compared with the application concentration of the active ingredient calculated from the insecticidal and acaricidal activity obtained in the laboratory, a sufficient control effect cannot be obtained unless a spray solution with a considerably high concentration is used, or the effect is not stable depending on the conditions. There was a point. Therefore, enhancement of efficacy and stabilization of biological effects in actual use were important subjects for formulation of this compound.

(Means for Solving the Problem) The compound represented by the formula (I) is solid at room temperature and has a solubility in water of 1.7 ppm (20 ° C.). In the case of an agricultural and horticultural preparation containing a solid having a low solubility in water as an active ingredient, the particle size of the active ingredient may affect biological activity.

The inventors of the present invention investigated the relationship between the particle size of the active ingredient and the biological activity of the compound of formula (I), and found that not only the particle size of the active ingredient but also the surface tension of the spray liquid greatly influences the biological effect. Found out. Therefore, the inventors have found that by optimizing the particle size of the active ingredient and the surface tension of the spray solution, the efficacy in actual use is enhanced and the biological effect is stabilized, and the present invention has been completed.

In the present invention, the active ingredient is finely pulverized to an average particle size of 5 μm or less. Such a particle size can be achieved by an appropriate dry or wet fine pulverizer. For example,
These are dry mills such as jet mills and ball mills, colloid mills and various sand mills, and wet mills such as attritors. Various carriers, wetting agents, dispersants, fluidity improvers, antistatic agents, thickeners, synergists and other auxiliaries can be added during pulverization. Further, in the case of a compounding agent, it is possible to grind it together with other active ingredients.

The active ingredient pulverized in this way can be used as it is as a wettable powder if a suitable auxiliary agent is mixed,
Since the compound of formula (I) has an extremely high biological activity, if the concentration of the active ingredient in the preparation is too high, the dilution factor becomes too large and it may be difficult to use. Therefore, in consideration of economic efficiency, generally, the mixture is ground in the form of a high-concentration premix containing an appropriate auxiliary agent, and the appropriate auxiliary agent is further added to prepare a wettable powder.

The wettable powder in the present application means a wettable powder in a broad sense including a suspension type FL agent and a DF agent in addition to the wettable powder in the narrow sense described above. However, as shown by the results of Test Example 3 described later, the active ingredient must be present in a solid state in these preparations. Therefore, the active ingredient is dissolved in an organic solvent, an emulsifier is added to form an emulsion, which is then absorbed by a carrier.A wettable powder or DF agent of the type in which the active ingredient is emulsified in water when diluted with water, or Emulsion type FL agents are not included in this application.

A wettable powder in a narrow sense can be directly obtained by mixing a carrier, a dispersant, a wetting agent, and various other auxiliaries at the time of pulverizing an active ingredient and pulverizing the whole amount, but more generally,
A suitable carrier, dispersant, wetting agent, adhesion improver, sticking agent, synergist, fluidity improver, dye or other auxiliary agent is mixed with a pulverized high-concentration premix of the active ingredient, and if necessary, It can be obtained by pulverizing and mixing again using an appropriate pulverizer.

The DF agent is basically a wettable powder in a narrow sense and is made into granules. Therefore, if necessary, a component similar to the above-mentioned wettable powder can be used.
It can be obtained by adding an appropriate water-soluble binder and water, granulating and drying, and sizing to an appropriate particle size range. As the granulator, a tumbling granulator, a mixing granulator, a fluidized bed granulator, an extrusion granulator, a spray dryer, a dry granulator or the like can be used. The binder used in the DF agent is preferably one that is easily soluble in water, and for example, a polycarboxylic acid type polymer dispersant, lignin sulfonate, low molecular weight dextrin or polyvinyl alcohol, carboxymethyl cellulose sodium salt, etc. are suitable. However, it is not limited to these. The particle size of the DF agent may be selected from the viewpoints of powderiness, fluidity, water dilutability, etc., but generally it is 0.
A range of about 1 to 1 mm is suitable.

The FL agent is a high-concentration premix of crushed active ingredients,
It can be obtained by adding water, a dispersant, a thickener, an anti-caking agent, an antifreezing agent, an anti-growth agent and the like to dilute.

In obtaining these wettable powders, the premix of the active ingredient to be used may be pulverized by a dry method or pulverized by a dry method, but considering the steps before and after, generally, For obtaining a wettable powder in a narrow sense, it is often advantageous to use a premix by a dry method and to obtain an FL agent, a premix by a wet method.

The particle size of the compound of formula (I) contained in the wettable powder of the present invention thus obtained has an average particle size of 5 μm or less.

The average particle diameter referred to in the present application means the mass-based median diameter when measured by the Andre-Aren pipette method. The density of the compound of formula (I) is 1.202 g / cm ³ . Than this,
Whether the average particle size is 5 μm or less is determined by the following.

(Measurement method of average particle size) An appropriate amount of a sample of 10 g or less is accurately weighed, and neogen powder (wetting dispersant containing sodium salt of dodecylbenzenesulfonic acid as a main component, Daiichi Kogyo Seiyaku Co., Ltd.) ) Made
Add about 400 ml of 0.2% aqueous solution and disperse for 5 minutes using an ultrasonic disperser with occasional stirring. The dispersion is washed with a standard Andre-Aren pipette with the same dispersion medium, and the whole volume is adjusted to the marked line with the dispersion medium. After placing the pipette in a thermostatic chamber adjusted to 20 ° C to make the liquid temperature constant, 20 hours 5 minutes 5 seconds after the start (time until 5 μm particles calculated by Stokes sedimentation equation settle to 20 cm) After the passage, the suspension at a depth of 20 cm is collected in a volumetric flask having a volume of 50 ml and adjusted to a constant volume with ethyl alcohol according to a conventional method.
When insoluble matter such as a carrier is present, it is filtered using a G-4 glass filter, and then the amount of the active ingredient is measured by the absolute calibration curve method using a liquid chromatograph set under the following conditions.

(Liquid chromatography conditions) Separation tube: Zorbax ODS 4.6 mm φ x 250 mm Eluent: Acetonitrile: Methanol: Water = 4: 1: 1 (1.5
ml / min) Measurement wavelength: 254 μm From the obtained amount of the active ingredient, the integrated particle size distribution at a particle size of 5 μm is calculated by the following formula. If the value obtained here is 50% or more, the average particle size is 5 μm or less.

Where m: amount of active ingredient obtained by the above method (m
g), V: Total amount of suspension in pipette (ml), M: Total amount of active ingredient collected in pipette (mg), v: Internal volume for pipette solution (ml) The component analysis method is an analysis method when there is no interference with quantification. When there is interference with quantification, establish a method for separating and analyzing the active ingredient by removing interfering substances by an appropriate purification method or changing the analysis conditions.

Further, the wettable powder of the present application requires that the surface tension of the diluted solution diluted with water to the use concentration is 50 dyn / cm or more.

Here, the surface tension of the diluted solution varies depending on factors such as the type and amount of the surfactant in the wettable powder, or the dilution ratio, but the surface tension of the diluted solution is 50 dyn / cm or more, and the desired value. The conditions such as the type and amount of the surfactant in the wettable powder, the dilution ratio, etc. can be arbitrarily selected as long as the biological effect is not impaired. For the surface tension, the surface tension at a liquid temperature of 20 ° C. is measured using a surface tension meter manufactured by Dunui.

Hereinafter, embodiments of the present invention will be described in more detail with reference to Test Examples and Examples, but the present invention is not limited thereto.

(Test Example 1) The compound represented by the chemical formula (1) was placed in a mortar, a 0.2% aqueous solution of neogen powder was added, and wet pulverization was performed. The pulverized product was diluted with the same dispersion medium, and wet classification was carried out for the A and B classifications by the wet sieving method, and the C to F classifications were repeated by the sedimentation method to classify into the particle size classifications shown in Table 1. Each particle size fraction was concentrated by centrifugation to give a suspension containing 5% of the compound of formula (I) and then diluted with water to obtain a diluted solution containing the compound of formula (I) at a concentration of 10 ppm. . The acaricidal activity of each of these samples was examined by directly spraying it on a leaf of a summer mandarin orange infested with female adults of citrus red mite and unhatched eggs using a Mizuho type rotary spraying tower.

As shown in Table 2, the test results showed high activity in the sample having an average particle size of about 5 μm or less, but the activity decreased when the particle size became larger than that.

(Test Example 2) The surface tension of the diluted solution of the classified sample of Test Example 1 was 69 dyn / cm.
Met. Regarding Sample E, when diluting the 5% suspension, a solution of Newcol 562 (polyoxyethylene nonylphenyl ether surfactant, manufactured by Nippon Emulsifier Co., Ltd.) was used to adjust the surface tension to 65,60 each. , 55,50,45,40,35,30,
The diluted solution was prepared so as to be dyn / cm. These dilute solutions were prepared to have an appropriate density in a state in which mites of all developmental stages were mixed together. Orange mandarin orange parasitic summer mandarin orange (tree height approx. 20 cm, 1 / 5000a Wagner pot planted, pre-spraying female mite density 2 5 heads / leaf) were sprayed with a spray gun in an amount sufficient for the drug solution to drip. After spraying, it was kept at room temperature without weathering. The control efficiencies after 4 weeks and 6 weeks are shown in Table 3.

When the surface tension of the diluted solution was 50 dyn / cm or more, high control efficiency was shown even after 6 weeks, but when the surface tension was lower than that, the lower the surface tension, the more the residual effect tended to be insufficient. .

The control efficiency was calculated by the following method.

However, n: number of surveys after spraying, C _b : density before spraying in non-scattering area, C _ai : density of i-th survey after spraying in non-scattering area, T _b : density before spraying in spraying area, T _ai : Density of i-th survey after application in application area (Example I) Wettable powder 5 parts of compound of formula (I), laberin FAN (condensate of sodium naphthalene sulfonate, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 10
Part, Neocor YSK (sodium salt of diethylhexylsulfosuccinic acid, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), 1 part, Carplex # 80 (hydrous silicon dioxide, Shionogi Pharmaceutical Co., Ltd.)
6 parts), Sieglite (kaolinite clay, manufactured by Sieglite Mining Co., Ltd.) 78 parts were mixed, and the air pressure was 6 kg / cm ² , using Jet omizer 0101 type (made by Seishin Enterprise Co., Ltd.). Grinding at a feed rate of 1.5 kg per hour gave a wettable powder containing 5% of the compound of formula (I). The average particle size of the compound of the formula (I) in the obtained wettable powder is 2.2 μm, and the surface tension of the diluted solution of 4000, 2000 times that of the wettable powder is 64,58 dy.
It was n / cm.

(Example 2) Flowable agent 15 parts of the compound of the formula (I), 1 part of Wetitol ssp (condensate of sodium phenolsulfonate, manufactured by BASF Corp.),
Mix 84 parts water with Dyno Mill KDL type (0.3L container, 1
Milling was performed for 25 minutes with 240 ml of glass beads of mmφ and a rotation speed of 3000 rpm). Separately, xanthan gum 0.3 parts, Veegum R (mineral thickener, Sanyo Chemical Industry Co., Ltd.) 2 parts, propylene glycol 15 parts, Toxanone GR31A (acrylic acid polysoap, Sanyo Chemical Industry Co., Ltd.) 1 part, Neocall YSK
Prepare a liquid that 0.2 parts, 48.2 parts of water are mixed well and dispersed,
To this, 33.3 parts of the above pulverized liquid was added and uniformly mixed to obtain a flowable agent containing 5% of the compound (1). The average grain size of the compound of formula (I) in the obtained flowable agent is 0.85μ.
The surface tension of the diluting solution of the flowable agent 4000 times and 2000 times was 66,64 dyn / cm, respectively.

(Example 3) Dry flowable agent A mixture of 95 parts of the compound of the formula (I) and 5 parts of granular calcium carbonate was pulverized by using a jet ohmicer under the same conditions as in Example 1. 5.3 parts of crushed product in a household mixer, 10 parts of sun extract P252 (sodium lignin sulfonate, manufactured by Sanyo Kokusaku Pulp Co., Ltd.), 3 parts of Polystar OMP (carboxylic acid type polysoap, manufactured by NOF CORPORATION), Amicole No. 1
(Enzyme-modified dextrin, manufactured by Nitto Kagaku Co., Ltd.) 5 parts, Zyklite 75.7 parts were added, and 1 part of HITENOL 05 (ammonium salt of polyoxyethylene alkyl ether sulfate, manufactured by Daiichi Kogyo Co., Ltd.) was mixed. Was dissolved in 13.5 parts of water, granulated, and dried at 50 ° C. 0.15-0.5m
The particles were sized into m sections to obtain a dry flowable agent containing 5% of the compound of formula (I). The average particle size of the compound of formula (I) in the obtained dry flowable agent is 2.75 μm, and the surface tension of the diluted solution of 4000, 2000 times is 58,54 dyn / each.
It was cm.

(Comparative Example 1) Wettable powder 5 parts of the compound of the formula (I), laberin FAN 10 parts, Neocor Y
5 parts of SK, 10 parts of Carplex # 80 and 70 parts of Sieglite were mixed and ground under the same conditions as in Example 1 to obtain a wettable powder containing 5% of the compound of formula (I). The average particle size of the compound of formula (I) in the obtained wettable powder is 2.2 μm,
The surface tension of the 00-fold diluted solution was 47.41 dyn / cm, respectively.

(Comparative Example 2) Wettable powder 5 parts of the compound of the formula (I), 10 parts of laberin FAN, Neocor Y
SK1 part, Carplex # 80 6 parts, Sieglite 78 parts are mixed, and Eck Sample Mill (manufactured by Fuji Paudal Co., Ltd.)
Was ground at a feed rate of 2.5 kg per hour to give a wettable powder containing 5% of the compound of formula (I). The average particle size of the compound of formula (I) in the obtained wettable powder is 14.8 μm, and the surface tension of the diluted solution of 4000, 2000 times the wettable powder is 63,55 dy.
It was n / cm.

(Comparative Example 3) Flowable agent 2 parts of the compound of the formula (I), 10 parts of methylnaphthalene and 0.5 part of the following compounding emulsifier were dissolved. In a separate container, 0.3 parts of xanthan gum, 2.0 parts of bigal R, propylene glycol 15.
Add 0 parts of this to 70.2 parts of water, add to this solution, and add TK homogenizer (made by Tokushu Kika Co., Ltd.)
Was mixed for 1 hour to obtain an emulsion type flowable agent containing 2% of the compound of the formula (I). The surface tension of the 1600,800 times diluted solution of the obtained flowable agent is
It was 65,60 dyn / cm.

Composition of compounded emulsifier Baytenol NF13 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 13.3% (ammonium salt of polyoxyethylene dinonyl phenyl ether sulphate) LAMIGEN ES60 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 13.3 (polyoxyethylene lanolin) Fatty acid ester) Newcol B-4 (Nippon Emulsifier Co., Ltd.) 53.4 (Polyoxyethylene naphthyl ether) Newcol 568 (Nippon Emulsifier Co., Ltd.) 20.0 (Polyoxyethylene nonylphenyl ether) (Comparative Example 4) Emulsion 5 parts of a compound of formula (I), parachol MBX (combined emulsifier,
20 parts of Nippon Emulsifier Co., Ltd. and 75 parts of xylene were mixed and dissolved to obtain an emulsion containing 5% of the compound of formula (I). The surface tension of 4000, 2000 times diluted solution of this emulsion is 45, 41 dy, respectively.
It was n / cm.

(Test Example 3) Using the samples of Examples 1 to 3 and Comparative Examples 1 to 4, in an actual field, an effect test against citrus red mite parasitic on Satsuma mandarin orange was conducted. The results are shown in Table 4.

All the samples of the examples showed high control efficiency even after 6 weeks, but in Comparative Example 1 (the particle size of the active ingredient is 5 μm or less in average particle diameter, the surface tension of the spray liquid is 50 dyn / cm or less). Wettable powder), Comparative Example 2 (surface tension of spray liquid is 50 dyn /
cm or more, but the particle size of the active ingredient is 5 μm or more in average particle size), Comparative Example 3 (surface tension of spray solution is 50 dyn /
cm or more, emulsion type flowable),
All the samples of Comparative Example 4 (emulsion having a low surface tension of the spray liquid) had poor residual effect and did not show satisfactory control efficiency after 6 weeks.

(Effects of the Invention) As described above, according to the present invention, the compound of formula (I) which is an active ingredient has an average particle size of 5 μm or less and a surface tension of 50 dyn / cm or more after spraying after dilution with water. A wettable powder prepared so that the compound of formula (I) can enhance the insecticidal and acaricidal activity in a practical use situation and can stably exhibit the acaricidal and acaricidal activity. The present invention not only contributes to the development of agriculture, but also achieves the purpose with a small amount of active ingredients, and is therefore beneficial in terms of environmental protection and economics.

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Satoru Nakajima 1041 Yasu-cho, Yasu-cho, Yasu-gun, Shiga In-house (72) Inventor Hiroshi Sahi 1041 Yasu-cho, Yasu-cho, Yasu-gun, In-house (72) Inventor Keiji Tanaka 1041 Yasu-cho, Yasu-cho, Yasu-gun, Shiga In-house (72) Inventor Shinji Yokoi 1041 Yasu-cho, Yasu-cho, Yasu-gun, Shiga Prefecture In-house

Claims (1)

[Claims] 1. A compound of formula (I) having an average particle size of 0.8 μm or more and 5 μm or less is used as an active ingredient and prepared so that the surface tension of a spray liquid after dilution is 50 dyn / cm or more and 69 dyn / cm or less. An insecticidal and acaricidal active wettable powder for agricultural and horticultural use characterized by the above.