JPH08225410A - Powdery germicidal composition - Google Patents

Abstract

PURPOSE: To obtain a powdery germicidal composition containing dithianon pulverized using an air mill, exhibiting excellent sterilizing effect, capable of providing a powdery preparation having lower concentration and improving economical efficiency and useful for preventing and treating melanose, scab, etc., of citrus fruits. CONSTITUTION: This composition contains 2,3-dicyano-1,4-dithiaanthraquinone (A) pulverized using an air mill. The composition is obtained as a wettable powder by adding 5-30% pulverizing auxiliary agent (e.g. tail oil, PAP, white carbon or talc) to the component A, pulverizing the mixture with an air mill, mixing the powder with a dispersing agent (e.g. an anionic surfactant or a nonionic surfactant) and a diluent (e.g. fine powder clay) and pulverizing the mixture.

Description

Detailed Description of the Invention

[0001]

The present invention relates to 2,3-dicyano-1,
It relates to an agricultural fungicide containing 4-dithiaanthraquinone (generic name dithianone). More particularly, it relates to an improved powdered fungicide composition containing dithianon.

[0002]

BACKGROUND OF THE INVENTION Dithianon is mainly used for citrus black spot, scab, anthracnose, pear black spot, scab, ring spot, etc., for peach, persimmon, grape, plum, apple, strawberry, konjac. ,
It is a fungicide that is highly effective against diseases such as tea, and its mechanism of action is thought to act on the protoplasm of pathogenic bacteria, enzymes, and thiol groups of proteins. And the bactericidal effect is superior to the preventive effect rather than the therapeutic effect.

Conventionally, in Japan, dithianon has been used mainly in the form of a wettable powder and, in a very limited field, in the form of a powder. In these powder formulations, dithianone drug substance (average particle size: around 10 μm) is not particularly crushed, and if it is a single agent, it is a dispersant, carrier, etc. And dispersant,
A product was obtained by mixing with a carrier and the like with a ribbon mixer, a Nauter mixer, etc., and lightly crushed with an impact type crusher such as a Nara type crusher, pin mill, hammer mill and the like. As a result, for example, dithianone 70% wettable powder having an average particle size of about 5 to 10 μ has been commercially available.

However, due to the situation of Japanese agriculture, raw material cost of dithianon drug substance, and soaring manufacturing cost,
Due to the need for more economical efficiency, a suspension formulation (flowable formulation) was developed in which the raw material of dithianon was wet-peptized using a bead mill or the like to have an average particle size of about 1 μm. Since this product can enhance the efficacy by reducing the particle size, a lower content of the flowable agent can be used at the same dilution ratio as compared with the wettable powder, and the dithianone drug substance can be saved accordingly. Specifically, a flowable agent containing 40% of dithianon is commercially available.

[0005]

However, this dithianon flowable agent has poor physical storage stability, and liquid separation and caking, which are considered to be caused by aggregation of the active ingredient, occur during storage, resulting in the formulation from the container. There may be problems such as hard to come out or not at all. On the other hand, powder formulations such as wettable powders and powders do not cause such problems,
Although it is physically stable, it is more economical than the flowable agent. The object of the present invention is to develop a more effective and economical powder formulation. As described above, when the dithianon drug substance is wet-peptized, it can be pulverized to the order of 1 μm. However, in order to use the ground product in a powder formulation, water as a medium must be removed by some means, which is expensive.

[0006]

The present inventors have found that a powdered bactericidal composition using dithianon pulverized with an air mill exhibits a high bactericidal effect. That is, although the dithianone drug substance pulverized with an air mill has an average particle size of about 3 to 5 μ even when the particle size distribution is measured, the powder formulation using it has a conventional dithianone drug substance. It was found that the composition has an extremely high effect as compared with the powder preparation using the average particle size (about 10 μm) as it is.

That is, the present invention relates to 2,3-dicyano-1,
Disclosed is a powder bactericide composition containing 4-dithiaanthraquinone (generic name; dithianone), which contains dithianone pulverized using an air mill.

In the present invention, the air mill is also called a jet mill, which is also called a jet mill, and is a fluid that moves at high speed (generally air).
It is a crusher that collides and crushes objects to be crushed. A vertical type jet-O-mizer type in which the crushing chamber is set upright and a horizontal type Ulmax type in which the crushing chamber is placed horizontally are included, and any of them can be adopted in the present invention.

Further, the object of the present invention can be achieved by mixing the raw material of dithianon with other raw materials such as a carrier and a dispersant and then pulverizing it with an air mill. From the standpoints of pulverization efficiency, abrasion inside the air mill, cost, etc., it is more preferable to pulverize the dithianon raw material in advance with an air mill and then mix it with other raw materials such as a carrier and a dispersant to prepare a product. This difference becomes larger as the dithianon content is lower.

When crushing the raw material of dithianon, it is usually preferable to add a small amount of a crushing aid. This has the function of increasing the efficiency of crushing and reducing the adhesion of crushed products inside the air mill. As the grinding aid, fatty acids such as tall oil and oily substances such as PAP can be considered, but amorphous silicon oxide (so-called white carbon), talc,
Fine mineral powder such as clay is preferable, and white carbon is particularly preferable because it does not wear the air mill. The amount added is required to be 5% or more, preferably 10% or more, relative to the drug substance. If the amount added is too large, the cost and the physical properties of the product are adversely affected, so it is necessary to keep it below 30%. When pulverizing with an air mill after mixing with other raw materials such as a carrier and a dispersant, it is not necessary to intentionally add a pulverizing aid.

The dithianon powder composition of the present invention is preferably a wettable powder. This is because dithianon does not have a permeation migration property, so it is not suitable for the form of granules.
This is because the dust is unlikely to adhere to crops. In the present invention,
These wettable powders are preferably made into a product by mixing a dithianone raw material (dithianon ground premix) ground by an air mill together with a grinding aid with a diluent such as a dispersant and a fine clay and ground.

As the dispersant used, various anionic surfactants, nonionic surfactants, etc. are used.
It has the function of maintaining the suspendability of the active ingredient particles in water, improving the wettability with water, and imparting hydration. The addition amount is 1 to 10%.

As the extender, fine mineral powder such as clay, calcium carbonate, zeolite, diatomaceous earth is used together with a grinding aid such as white carbon. In addition, defoaming agents, anti-caking agents and the like can be added as necessary.

In the wettable powder, the content of dithianon is preferably 5 to 80%. As described above, since 70% of the conventional dithianone wettable powder is sold, when the wettable powder of the present invention has a content of 70%, the wettable powder of the present invention is more suitable than the conventional 70% wettable powder when used. The water dilution ratio can be increased. on the other hand,
If the content of the wettable powder is 35 to 50%, it can be used at almost the same dilution ratio as the conventional wettable powder.

The powder formulation of the present invention can also be made into a powder. Since the dust is generally applied as it is to the crop without being diluted, the content of dithianon is preferably set to 1 to 10%. As the powder, clay, calcium carbonate, and talc are used as a bulking agent, as well as white carbon,
Auxiliary agents such as diatomaceous earth, PAP (isopropyl acid phosphate), fatty acids, vegetable oils, and paraffin are added and used for the purpose of grinding aid and physical property improver. Clays (so-called cut clay or DL clay) from which powder of 5 μm or less has been removed are used as the extender.
The one to which a flocculant such as (Sankyo Co., Ltd. product name) is added is a so-called D in which the drift of the drug outside the purpose is reduced.
It is an L powder, and the powder formulation of the present invention can also be in this form.

The powder formulation of the present invention can be added with an agricultural chemical component other than dithianon to enhance the bactericidal effect, broaden the spectrum, or impart an insecticidal effect. Preferred mixed components include cupric hydroxide, 8-hydroxyquinoline copper, copper agents such as basic copper chloride, thiophanate methyl,
Benzimigzole agents such as thiabendazole, iprodione, vinclozolin, dicarboximide agents such as procymidone, EBI agents such as triflumizole and phenalimol, dithiocarbamates such as zineb, manneb and thiuram, metalaxyl, captan,
Examples include streptomycin.

[0017]

In the present invention, even if the raw material of dithianon is crushed by an air mill, the crushing effect is not so great in terms of particle size distribution. However, the powder bactericidal composition of the present invention can remarkably enhance the efficacy as compared with the conventional powder bactericidal composition. The reason for this is not clear, but it is presumed that the surface of the dithianone conformal particles is involved.

[0018]

EXAMPLES Next, the present invention will be described with reference to examples.

[0019]

[Pulverization example 1] Dithianon drug substance (purity 92.6%, 45μ
10% of Carplex # 80 (Shionogi Pharmaceutical Co., Ltd. white carbon) was mixed with the sieve passing 97.3%) and Jet-O-Mizer (FS-4 manufactured by Seishin Enterprise Co., Ltd.) was mixed.
Type). The air pressure was 7 kg / cm ² , and the feed rate was 0.3 kg / hr. Is. The content of dithianone in the obtained dithianone crushed premix was 83.1%, and the 45μ sieve was passed through. Table 1 shows the particle size distributions of the used dithianon raw material and the ground dithianon premix by a laser diffraction type particle size distribution analyzer.

[0020]

Grinding Example 2 The dithianon ground premix obtained in Grinding Example 1 was ground again under the same conditions. The content of dithianon in the obtained ground premix was 83.4%. The particle size distribution of this product is also shown in Table 1.

[0021]

Example 1 86.6 parts of the dithianon ground premix obtained in Grinding Example 1 was mixed with 2 parts of sodium polyoxyethylene alkylphenol ether sulfate, 2 parts of sodium naphthalene sulfonate condensate and 9.4 parts of finely powdered clay. , 70% wettable powder was obtained. The dithianon content in this wettable powder was 71.8%. The particle size distribution of this product is shown in Table 1.
Shown in

[0022]

[Comparative Example 1] The procedure of Example 1 was repeated except that the crushed premix was replaced with 77.8 parts of undiluted dithianon raw material (used in Grinding Example 1) and 18.2 parts of fine clay. A 70% wettable powder was obtained in the same manner as in Example 1. The content of dithianon in this wettable powder was 72.1%. The particle size distribution of this product is shown in Table 1.

[0023]

[Comparative Example 2] New Cargen FS- in a stainless steel container
7 (Takemoto Yushi Co., Ltd. anionic surfactant) 5.6
Parts, 5.6 parts of propylene glycol, 38.6 parts of water, and 0.2 parts of Pronal EX-300 (an antifoaming agent manufactured by Toho Chemical Industry Co., Ltd.) are mixed and dissolved. To this, 50 parts of dithianon raw material (93.0%) is added little by little, and when uniform, glass beads (φ1 mm) are added in substantially the same volume, and the mixture is stirred at high speed for 4 hours with a wheel-shaped stirring blade to peptize. This peptizer 9
To 0 part, 10 parts of an aqueous solution of 1% Kelzan S (xanthan gum manufactured by Kelco, USA) + 2% Proxel GXL (preservative manufactured by Zeneca Corporation) was mixed to obtain 40% flowable. The content of dithianon in this flowable agent is 4
1.9%, and the particle size distribution is shown in Table 1.

In Table 1, the dithianon raw material used in Grinding Example 1 and its air mill grinding premix, the grinding premix of Grinding Example 2, the wettable powder of Example 1, the wettable powder of Comparative Example 1 and the wettable powder of Comparative Example 2 were prepared. 1 shows a particle size distribution of a flowable agent measured by a laser diffraction type particle size distribution measuring device.

[0025]

[Table 1]

From these results, it appears that even if the dithianone raw material is pulverized by the air mill, the particle size is only reduced to about half, and even if it is passed through the air mill twice, it does not become thinner. On the other hand, it can be seen that the flowable agent obtained by wet peptization is thinned to about 1/10.

[0027]

Example 2 A 40% wettable powder was obtained in the same manner as in Example 1 except that 50.5 parts of the dithianon crushed premix and 45.5 parts of finely divided clay were used. The dithianone content was 42.1%.

[0028]

Example 3 A 40% wettable powder was obtained in the same manner as in Example 2, except that the dithianon crushed premix was replaced with the crushed premix obtained in Grinding Example 2. Dithianon content is 4
It was 2.0%.

[0029]

Example 4 31.5 parts of the dithianon crushed premix of crushed example 1 and 8-hydroxyquinoline copper (purity 90.5
%) 40.7 parts, sodium lignin sulfonate 4
Part, 3 parts of Lunox P-65L (Toho Chemical Industry Co., Ltd. anionic surfactant), 1.5 parts of Carplex # 80, 19.3 parts of finely divided clay, dithianon (25%), organic copper A (35%) mixed wettable powder was obtained.

[0030]

Example 5 Dithianon Grinding Premix 5 of Grinding Example 1
0.5 part, Topgin M bulk powder (manufactured by Nippon Soda Co., Ltd., purity 97.3%) 31.8 parts, Newcalgen NX-17
0 (Takemoto Yushi Co., Ltd.) 6.5 parts, sodium alkylbenzene sulfonate (60% product) 3 parts and fine powder clay 8.2 parts were mixed, and dithianon (40%) and thiophanate methyl (30%) were mixed. A wettable powder was obtained.

[0031]

Example 6 3 parts of the dithianon ground premix of Grinding Example 1, 16 parts of cupric hydroxide premix (purity 51.1%), and 81 parts of clay were mixed to give dithianone (2.5%).
%) Copper (5.2%) mixed powder was obtained.

[0032]

[Test Example 1] The harvested Satsuma mandarin orange fruits were sprayed with a sufficient amount of the agents of Examples 1 and 3 and Comparative Examples 1 and 2 diluted to a predetermined concentration, air-dried, and then 10 ⁵ pieces / 1 ml.
Pepper cloth soaked with citrus black spot fungus spore suspension (5m
(m square) was attached to the surface of the fruit and stored in a plastic bag. Two weeks later, the incidence and extent of disease were investigated. Using 3 fruits per ward, inoculation was carried out at 6 to 9 places per one, and the degree of disease was quantified according to the following criteria. No illness ... I, illness has occurred, but the shape of the smooth cloth is vague ... II, part of the shape of the smooth cloth is clearly visible ...
III, the whole shape of the smooth cloth can be clearly understood .... IV Table 2 shows the results.

[0033]

[Table 2]

[0034]

[Test Example 2] Example 2 and Comparative Example 1 for potted 20th century pears
After diluting the wettable powder of the above to a predetermined concentration, spraying it, and air-drying it, conidial suspension of black spot fungus (spore concentration: 20/10)
(0x1 field) was uniformly sprayed. After being placed in a humid chamber at 28 ° C. for 1 day, it was grown in a glass greenhouse, and after 20 days, the disease state was examined. It was carried out in 1 ward and 1 pot in duplicate. The results are shown in Table 3.

[0035]

[Table 3]

[0036]

As is clear from Tables 2 and 3, the wettable powders of Examples 1 to 3 using the dithianone raw material crushed by the air mill are obviously the same as those of Comparative Example 1 prepared in the same manner as the conventional method. Effectively superior to wettable powder. From the particle size distribution shown in Table 1, the difference in potency between these wettable powders was completely unexpected. By using the air-milled dithianone drug substance, it is possible to obtain a powder formulation having a lower concentration that can be used at the same dilution ratio, and it is possible to improve the economical efficiency.

Claims (1)

[Claims] 1. A powder bactericide composition containing 2,3-dicyano-1,4-dithiaanthraquinone, which comprises the active ingredient pulverized with an air mill. Stuff.