JPH1029905A - Stabilization of flowable preparation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of inhibiting the increase of particle sizes of dymron during the storage. SOLUTION: A herbicide, dymron is allowed to coexist with a small amount of at least one among N,N'-bis(α,α-dimethylbenzyl)-urea and N-(α,α- dimethylbenzyl)-N'-m-tolylurea.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to N- (α, α-dimethylbenzyl) -N′-p useful as a paddy field herbicide.
The present invention relates to a method for stabilizing a flowable preparation containing tolyl urea (generic name: Daimron), and more particularly to a method for preventing an increase in the particle size of Daimron in a flowable preparation.

[0002]

2. Description of the Background Art Daimlon is a non-hormonal herbicide with absorption and transferability, and is highly safe against rice.
Acts specifically on weeds of the family Cyperaceae, such as pine flies, fireflies, spiders and black clovers in paddy fields. On the other hand, since the effect is not always sufficient for grasses and broadleaf weeds, it is generally used in practice as a mixture with other active ingredients that are effective against them. In particular, for sulfonylurea herbicides that are effective in controlling broadleaf weeds in recent years,
Since its action to reduce phytotoxicity has been recognized, its use as a mixture with these has been increasing.

[0003] Initially, there were many types of preparations in the form of granules, but recently, they can be uniformly dispersed with good diffusibility into paddy fields. Because of ease of use, it is often used as a flowable preparation.

[0004] A flowable preparation is a preparation in which a solid active ingredient insoluble in water is pulverized into fine particles and dispersed in water using a dispersant, and is also called a suspension preparation or a sol. The appearance is cloudy and opaque, and the preparation is usually stabilized by adding a protective colloid agent, a thickener and the like.

[0005] In the case of Daimlon and a flowable preparation containing the same and other active ingredients, usually, Daimlon and other active ingredients to be used in combination, if necessary, are pulverized into fine particles of about 0.5 to 5 µm, and this is anionic surfactant. Is dispersed in water together with a dispersant selected from a nonionic surfactant or a nonionic surfactant. However, depending on the conditions during storage, sometimes the particle size of Daimron increases, the stable suspension state is lost, As a result, smooth application at the time of use is hindered, and uniform application is hindered, so that sufficient efficacy may not be expected in some cases.

[0006]

DISCLOSURE OF THE INVENTION The present invention relates to a flowable preparation containing Daimlon as at least one of the active ingredients, which has excellent original properties, that is, the herbicidal action of the active ingredient and the properties of the preparation without any deterioration during storage. Therefore, it is intended to provide a method for preventing and increasing the particle size of Daimlon in the above.

[0007]

The present inventor has conducted various studies to solve the above-mentioned problems, and as a result, has found that a small amount of N, N'-
Bis (α, α-dimethylbenzyl) -urea or N-
The present inventors have found that the desired object can be achieved by coexisting at least one kind of (α, α-dimethylbenzyl) -N′-m-tolylurea, and completed the present invention.

That is, the present invention provides: 1) N- (α, α-dimethylbenzyl) as an active ingredient
In a flowable preparation containing -N'-p-tolyl urea, a small amount of N, N'-bis (α, α-dimethylbenzyl) -urea and N- (α, α-dimethylbenzyl)-
N- (α, α-dimethylbenzyl)-characterized by coexisting at least one kind of N′-m-tolyl urea
A method for preventing an increase in the particle size of N'-p-tolyl urea; 2) N, N'-bis (α, α-dimethylbenzyl) -urea or N- (α, α-dimethylbenzyl) -N'- m
The amount of tolyl urea is 0.01 to 5.0 with respect to the active ingredient N- (α, α-dimethylbenzyl) -N′-p-tolyl urea;
3) N, N′-bis (α, α-dimethylbenzyl) -urea and N- (α, α-dimethylbenzyl) -N′-m
-It is intended to provide the method as described in 1 above, wherein tolyl urea is allowed to coexist.

Hereinafter, the method of the present invention will be described in more detail. The method for preparing a flowable formulation containing Daimlon in the method of the present invention itself is not particularly limited, and a method known as a general method for preparing an agricultural chemical flowable formulation is applied. That is, Daimlon and other active ingredients are pulverized together with a dispersing agent, a protective colloid agent or a thickening agent, an antifreezing agent, an antifoaming agent, a wetting agent and the like by a wet method or a dry method to prepare a mixture.

[0010] Other active ingredients used together with Daimulon include, for example, imazosulfuron (generic name of agricultural chemical; the same applies hereinafter), pyrazosulfuron, bensulfuron-methyl,
Ethoxysulfuron, cyclosulfamuron, pentaxazone, dimethaline, naproanilide, benzofenap, plethychlorl, tenylchlor, mefenacet, cafenstrole, esprocarb, amylophos, cyhalofop butyl, pyriminobac-methyl, etc.
MK243 (test name, same hereafter), MY100, NBA
061 or a mixture of two or more thereof.

Examples of the dispersant include alkyl benzene sulfonate, alkyl naphthalene sulfonate, alkyl aryl sulfonate, alkyl naphthalene sulfonate formalin condensate, lignin sulfonate, dialkyl sulfosuccinate, Anionic surfactants such as alkyl sulfate, polyoxyalkylene alkylaryl ether sulfate, polyoxyalkylene alkylaryl phosphate, polycarboxylate, or, for example, polyoxyalkylene alkyl ether, polyoxyalkylene alkyl phenyl ether, polyoxy Alkylene aryl ether, polyoxyalkylene alkyl aryl ether, polyoxyalkylene alkyl ester, sorbitan alkyl ester Nonionic surfactants such as polyoxyalkylene sorbitan alkyl esters.

As protective colloids or thickeners, for example, gum arabic, guar gum, sodium alginate,
Gelatin, casein, carboxymethyl cellulose, xanthan gum, welan gum, ramzan gum, sodium polyacrylate, polyvinylpyrrolidone, polyvinyl alcohol, maleic anhydride styrene copolymer, water-soluble polymer substances such as soluble starch, or, for example, montmorillonite, smectite, Inorganic substances such as veegum are used. Further, as the antifreezing agent, for example, ethylene glycol, propylene glycol, glycerin, urea, an alkali halide, or the like is used, and as the defoaming agent, a silicone resin emulsion or the like is used.

In the case of the wet method, which is generally used, water as a dispersion medium is added to the above-mentioned components to form a mixture of 0.5 to 5 μm.
It is prepared by grinding to a degree, usually around 2 μm. There is no particular limitation on the content of Daimlon as an active ingredient, but it is blended in a range of about 0.5 to 60% by weight, usually about 5 to 40% by weight, and a mixing ratio with other active ingredients. Although there is no particular limitation, it is usually added in a range of about 0.01 to 2% by weight based on Daimlon.

The flowable preparation containing Daimlon is a relatively stable preparation under normal conditions due to the incorporation of the above-mentioned dispersant, protective colloid agent (thickener), etc., but sometimes causes an increase in particles. Problems such as those described above may occur. The solubility of Daimlon in water at room temperature is 1.7pp
m, which can be said to be almost insoluble, but when it is used as a flowable formulation, its solubility changes due to the influence of other ingredients, and a small amount dissolves during storage, and this precipitates out and aggregates or grows around fine particles. However, it is thought that the particles may increase in some cases, but the exact cause is not always clear.

However, a small amount of N, N'-bis (α, α-
The coexistence of at least one of dimethylbenzyl) -urea and N- (α, α-dimethylbenzyl) -N′-m-tolylurea suppresses the increase of the particles. These can be used alone, and the former is particularly effective, but both may be combined. The amount to be blended is not strictly limited, but is suitably about 0.01 to 5.0% by weight with respect to Daimlon. If the amount is too small, it is difficult to expect a sufficient effect. On the other hand, if the amount is used in an excessively large amount, the suppression effect can be obtained as it is, but there is a possibility that a problem may occur in the original characteristics of the agricultural chemical formulation. Usually 0.1 ~ 1.0
A practically sufficient effect can be obtained in the range of weight%. An example of a formulation of a stabilized Daimlon flowable according to the present invention is shown below.

Daimlon 400-600 g / l N, N′-bis (α, α-dimethylbenzyl) urea and / or N- (α, α-dimethylbenzyl) -N′-m-tolyl urea 0.4-6 g / l Surfactant 40-80 g / l Antifreeze 0-80 g / l Antifoam 1-2 g / l Thickener 1-30 g / l Water Suitable amount

[0017]

EXAMPLES The method of the present invention will be described in more detail with reference to representative examples. However, these are merely examples for explanation, and therefore, the present invention is not limited only to these examples. Parts in the following examples are parts by weight unless otherwise specified.

Example 1 30 parts of Daimlon, 0.06 part of N, N'-bis (α, α-dimethylbenzyl) -urea, 3 parts of dispersant (polyoxyalkylenealkylarylphenyl ether), defoamer (silicone resin emulsion) Ion-exchanged water was added to 0.2 part and 6 parts of an antifreezing agent (propylene glycol) to make the total amount 93 parts, and they were mixed uniformly using a homogenizer. This mixed solution is mixed with glass beads having a diameter of 1.0 to 1.5 mm in a 0.3-liter container using a horizontal sand mill grinder.
Using 0 ml, the mixture was pulverized until the average particle size became about 2 μm. On the other hand, 2 parts of a thickener (Xanthan gum) and 2 parts of a fungicide were added to 96 parts of ion-exchanged water and dispersed to prepare a thickening liquid. Thickening liquid 7 prepared in 93 parts of the pulverized liquid of Daimlon
Was added to make the total amount 100 parts, thereby obtaining a 30% flowable Daimlon agent.

Example 2 Instead of 0.06 part of N, N'-bis (α, α-dimethylbenzyl) -urea of Example 1, 0.15 part of N- (α, α-dimethylbenzyl) -N'-m-tolyl urea , And the same operation as in Example 1 was performed to obtain a 30% flowable agent of Daimlon.

Comparative Example 1 The same operation as in Example 1 was carried out except that N, N'-bis (α, α-dimethylbenzyl) -urea was not added to the formulation of Example 1, except that Daimlon's 30% flowable agent was used. I got

Test Example 30% of Daimlon obtained in Examples 1 and 2 and Comparative Example 1
The flowable agent was left in a thermostat at 25 ° C., and the average particle diameter in each suspension was measured at predetermined intervals by a laser type particle size distribution analyzer. The results are shown in the following table.

[0022]

[Table 1] Average particle size (μm) Immediately after preparation 1 day later 1 week later Flowable agent of Example 1 1.9 1.9 1.9 Flowable agent of Example 2 1.9 2.0 2.0 Flowable agent of Comparative Example 1 .9 2.4 3.8

From the table, it can be seen that the flowable agent not containing the substance of the present invention obtained in Comparative Example 1 had an average particle size of about 2 weeks after one week.
Although the substance of the present invention N, N'-bis (α, α
-Dimethylbenzyl) -urea in Example 1 and N- (α, α-dimethylbenzyl) -N′-m-tolylurea in Example 2 had very low average particle diameters. It turns out that it is stable.

[0024]

According to the present invention, the excellent properties inherent in the flowable preparation containing Daimlon as at least one of the active ingredients, that is, the herbicidal action as a paddy herbicide and the characteristics of the flowable preparation itself are impaired at all. In addition, depending on the conditions during storage, an increase in the particle diameter of Daimlon, which is sometimes a cause of the loss of a stable suspension state, can be prevented by a simple method.

Claims (3)

[Claims] 1. A flowable preparation containing N- (α, α-dimethylbenzyl) -N′-p-tolylurea as an active ingredient, comprising a small amount of N, N′-bis (α, α-dimethylbenzyl) -urea. And N- (α, α-dimethylbenzyl) -N′-m-tolylurea in the presence of at least one of N- (α, α-dimethylbenzyl) -N′-m-tolylurea. A method for preventing an increase in particle size. 2. N, N′-bis (α, α-dimethylbenzyl) -urea or N- (α, α-dimethylbenzyl)
The amount of -N'-m-tolylurea depends on the active ingredient N- (α, α
-Dimethylbenzyl) -N'-p-tolylurea
The method according to claim 1, wherein the amount is 0.01 to 5.0% by weight. 3. N, N′-bis (α, α-dimethylbenzyl) -urea and N- (α, α-dimethylbenzyl)
The method according to claim 1, wherein -N'-m-tolyl urea is allowed to coexist.