JPH0466509A - Granular herbicide for paddy field - Google Patents

Abstract

PURPOSE:To obtain the subject granular herbicide applicable without causing the trouble of the flotation of small hydrophobic particles on water surface by combining small hydrophobic particles containing a sulfonylurea compound enclosed therein with fine powder of calcium carbonate and a specific compound or further with a herbicide effective to barnyard grass. CONSTITUTION:The objective herbicide can be produced by uniformly mixing (A) small hydrophobic granules containing a sulfonylurea compound enclosed therein, (B) fine powder of calcium carbonate or an inorganic mineral composed mainly of calcium carbonate and (C) a compound of formula (R is 11-20C straight or branched chain alkyl; X is H, univalent metal atom or ammonium) or further with (D) one or more herbicidal components effective against barnyard grass which is a weed in paddy field and granulating the obtained mixture by an extrusion granulation method. The flotation of the small hydrophobic granules in the agent on water surface can be almost completely prevented. Since there is no flotation of the agent on water surface, the phytotoxicity to rice plant can be prevented and the herbicidal effect can fully be exhibited over the whole paddy field.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel granule for weeding rice fields, which prevents herbicidal active ingredients from floating to the water surface after application of the granules.

[Conventional technology and issues]

In recent years, sulbonyl urea compounds have been found to have high activity as herbicidal active ingredients for weeding rice fields, and have been put to practical use in the form of granules.

Because this sulfonylurea compound is highly active, it is necessary to control the sulfonylurea compound so that it is released little by little from the granule after it is applied to paddy water in the form of granules. For this purpose, the production of microscopic hydrophobic particles containing sulfonylurea compounds wrapped in paraffin wax was investigated, and a technique for controlling the release of sulfonylurea compounds, that is, sustained release of sulfonylurea compounds, was completed. However, after application to paddy fields, these micro hydrophobic particles are sometimes found to float on the water surface depending on the paddy field conditions.

When microscopic hydrophobic particles float to the water surface, they are blown away by the influence of the wind, and these microscopic hydrophobic particles concentrate in the leeward area, causing chemical damage to rice plants and making the weeding effect of the entire paddy field insufficient.

Therefore, preventing micro hydrophobic particles from floating to the water surface is an extremely important issue.

[Means to solve the problem]

The present inventors have completed the present invention by discovering that by applying the granules for rice fields of the present invention to rice fields, most of the micro hydrophobic particles in the granules can be prevented from floating to the water surface.

That is, the present invention provides water-disintegrating granules in which each of the following substances (1), (2), and (2) is uniformly mixed or
The present invention relates to a novel granule for weeding rice fields, which is obtained by uniformly mixing the substances (1) and (2) and granulating the mixture by extrusion granulation.

■Minute hydrophobic particles enclosing a sulfonylurea compound, ■Calcium carbonate or inorganic mineral fine powder mainly composed of calcium carbonate, ■-General formula■] R-0-CO-CH-3O3X R-0-CO-CH2 (I) (wherein R represents a linear or branched alkyl group having 11 to 20 carbon atoms, and X represents a hydrogen atom, a -valent metal atom or an ammonium group) , ■One or two herbicidal active ingredients effective against barnyard grass, a rice field weed.
Ingredients that are more than seeds.

Each of the above substances ■, ■, ■, ■, as necessary,
General binders, dispersants, disintegrants, etc. for granules may be added, and stabilizers may also be added.

First, as a method for producing micro hydrophobic particles enclosing a sulfonylurea compound, for example, a sulfonylurea compound, paraffin wax, and fine mineral powder such as gicrite are uniformly mixed in an appropriate ratio, melted, and granulated. to obtain micro hydrophobic particles.

Next, these micro hydrophobic particles, calcium carbonate alone or an inorganic mineral fine powder mainly composed of calcium carbonate, a compound represented by the above general formula [1), and optionally a herbicidal activity effective against barnyard grasses. The ingredients and, if necessary, a dispersant (e.g. sodium tripolyphosphate, lignin sulfonate) are mixed evenly, a small amount of water is added, kneaded, extruded and granulated, dried, sized, and sieved. The granules for weeding rice fields of the present invention are obtained.

In the present invention, the sulfonylurea compound is not particularly limited, but examples thereof include N-[:(4,6-simetogycypyriminon-2-yl)aminocarbonylcy4-ethoxycarbonyl- 1-methylpyrazole-5
-sulfonamide and methyl-1-[([([(4,
6-Simethoxypyrimicin-2-yl)amino]carbonyl]amine]sulfonyl]methyl]benzoate.

Although paraffin wax is not particularly limited,
For example, it is desirable that it be solid at room temperature.

Examples of the mineral fine powder include clay, talc, bentonite, and diatomaceous earth.

Herbicidal active ingredients effective against barnyard grass are not particularly limited, but include, for example, the following.

[1F Quinclorac (generic name) 3,7-dichloro-8-quinolinecarboxylic acid [21 Bretilachlor (generic name) 2-chloro-2,6"-diethyl-N-(n-propoxyethyl)acetanilide [31 Mefenacet (Generic name) 2-benzothiazol-2-yloxy-N-methylacetanilide [4]bromobutide (Generic name) (R3)-2-bromo-N-(α,α-dimethylbenzyl)-3,3-dimethylbutyl Amide [51 molinate (generic name) S-Ethylhexahydro-IH-azepine-1-carbothioate [6] dimethamethrine (generic name) 2-Methylthio-4-ethylamino-6-(1,2 diethylpropylamino) -3-triazine and the like.

In the compound represented by the general formula (I), R is preferably a linear or branched alkyl group having 12 to 17 carbon atoms, and X is an alkali metal atom.

Next, specific examples and test examples will be given and explained.

In addition, in the following Examples, Comparative Examples, and Test Examples, Compound A is N-[(4,6-dimethoxypyrimidine-2
-yl)aminocarbonyl-4-ethoxycarbonyl-1-methylpyrazole-5-sulfonamide,
Compound B means methyl 2-[([([(4,6-dimethoxypyrimidin-2-yl)amino]carbonyl]amino]sulfonyl]methyl]benzoate.

Examples of the compound of general formula [I] used in the present invention are as follows, but the compound is not limited thereto.

(Hereinafter, blank space) R-0-Co-CH-3O3X R-0-Co-CH2(I) Compound Compound (1) Compound (2) Comparative compound (1) C13H2□ CI SH31 C1°H21 The following examples and Parts in the comparative examples mean parts by weight.

(Hereinafter, blank space) Example 1 Compound A 7 parts Solid paraffin wax -100 parts Calcium carbonate -1-100 parts After uniformly mixing the above components, 71'C Melt and granulate the powder to a particle size of approximately 0.
．． Fine hydrophobic particles containing 3.38% of Compound A are obtained by pulverizing the particles to a size of 5 mm or less.

In addition, in the following examples, the micro hydrophobic particles containing compound A are referred to as micro hydrophobic particles A, and the micro hydrophobic particles produced according to Example 1 by replacing compound A with compound B are referred to as micro hydrophobic particles B. .

Example 2 Micro hydrophobic particles A ・−・−・−・ 2.0
7 parts Calcium carbonate −・−・・・・ 79
．． 93 parts bentonite - 11112
Partial compound (1) ...--1
1 part Sodium ligninsulfonate ・・・-5 parts Mix the above ingredients uniformly, add an appropriate amount of water and knead to form a 1 m diameter
The granules are extruded and granulated using a No. m screen, and the granules are dried, sized, and sieved to obtain the granules for weeding rice fields of the present invention. This granule is referred to as the granule (1) of the present invention.

Example 3 Micro hydrophobic particles A --2,07 parts Quinclorac (generic name) --0,9 parts Calcium carbonate
-89.03 parts Bentonite compound (2) -2 parts Sodium lignin sulfonate 1 part Mix the above ingredients uniformly, add an appropriate amount of water and knead to give a diameter of 1 mm.
The granules are extruded and granulated using a screen, and the granules are dried, sized, and sieved to obtain the granules for weeding rice fields of the present invention. This granule is referred to as the granule (2) of the present invention.

Example 4 Micro hydrophobic particles B -- 2.077 parts Calcilla carbonate, -- 73.93 parts bentonite -- 20 Fine compound (I) --
- 1 part Sodium ligninsulfonate - 2 parts Solbol-5060 [manufactured by Toho Chemical (disintegrant)] 1 - 1 part Mix the above ingredients evenly, add an appropriate amount of water and knead, diameter 1 m.
The granules are extruded and granulated using a No. m screen, and the granules are dried, sized, and sieved to obtain the granules for weeding rice fields of the present invention. This granule is referred to as the granule (3) of the present invention.

Example 5 Micro hydrophobic particles B -- 2.07 parts Mefenacet (generic name) -- 3. 5 parts calcium carbonate 83. 43 parts bentonite 10 parts compound (1)
1 part The above ingredients are uniformly mixed, an appropriate amount of water is added, kneaded, extruded and granulated through a screen with a diameter of 1 mm, and the granulated product is dried, sized, and sieved to obtain the granules for weeding rice fields of the present invention. get the agent. This granule is referred to as the granule (4) of the present invention.

Next, a formulation example of a comparative granule as a comparative example is shown.

(Hereinafter, blank space) Comparative Example 1 Micro Hydrophobic Particles A 2.07 parts Calcium carbonate - 79. 93 parts Bentonite comparative compound (1) 1 part Sodium lignin sulfonate 5 parts The above and others were mixed uniformly, an appropriate amount of water was added, kneaded, extrusion granulated by extrusion through a screen with a diameter of 1 mm, and the granulated product was It is dried, sized, and sieved to obtain comparative water a1 herbicidal granules. This granule is referred to as comparative granule (1).

Comparative Example 2 Micro Hydrophobic Particles A Quinclorac Calcium Carbonate Bentonite Polyoxyethylene Nonylphenyl Ether = 2 parts The above ingredients were mixed uniformly, an appropriate amount of water was added and kneaded, and the mixture was extruded and granulated through a screen with a diameter of 1 mm. This granulated material is dried, sized,
The rice field weeding rain drops 2, 07 parts 0, 9 parts 75, 03 parts 20 parts (common name) were obtained by sieving. This granule is referred to as comparative granule (2).

Comparative Example 3 Micro Hydrophobic Particles 8 2.07 parts Mefenasetl- (generic name) 3.5 parts Calcium carbonate
77, 43 parts bentonai)・1
5 parts Sodium lignin sulfonate 2 parts Mix the above ingredients uniformly, add an appropriate amount of water and knead to obtain a diameter of 1r++.
Extrusion granulation is performed using a screen No. 20, and the granulated product No. 20 is dried, sized, and sieved to obtain a comparative granule for weeding rice fields. This granule is referred to as comparative granule (3).

(Hereinafter, blank space) Test Example 1 Weighed 00 g of each granule i of the above examples and comparative examples, and added this granule to 500 g of hard water with a hardness of 3 degrees.
The water was poured uniformly into each beaker from a position 10 cm above the water surface.

The introduced granules settled and spread uniformly over the bottom of the beaker.

Three hours after the addition, all microscopic hydrophobic particles floating on the water surface were scooped out with a filter paper and air-dried on the filter paper for a day and night to remove water, and then the weight of the amount floating on the water surface was measured.

The water surface floating rate was calculated using the following formula.

The results are shown in Table 1.

F: Water surface floating rate (%) (hereinafter, blank) Table 1 Sample granules Active ingredient Additive F (%) Granules of the present invention (1) A Compound (1) 0 Granules of the present invention (2)
) A + [1] Compound (2) 0 Granules of the present invention (3
) B Compound (1) 0 Granules of the Present Invention (4) B
+ [3] Compound (2) 0 Comparative granules (1) A
Comparative compound (1) 6 Comparative granule (2) A+[l
] P, 0. E 32 In Table 1, A refers to compound A, B refers to compound B, [11 refers to quinclorac (generic name), [3] refers to mefenacet (generic name),
Compound (1) is a dialkyl sulfosuccinate in which R represents an alkyl group having 13 carbon atoms, compound (2) is a dialkyl sulfosuccinate in which R represents an alkyl group having 15 carbon atoms, and comparative compound (1) is a dialkyl sulfosuccinate in which R represents an alkyl group having 15 carbon atoms. Dialkyl sulfosuccinate representing an alkyl group having 10 carbon atoms, P,
0. E represents polyoxyethylene nonylphenyl ether.

As is clear from Table 1, the dialkyl sulfosuccinate-containing granules and polyoxyethylene nonylphenyl ether-containing granules in which R represents an alkyl group with 10 carbon atoms prevent micro hydrophobic particles from floating on the water surface. However, the granules containing dialkyl sulfosuccinate in which R represents an alkyl group having 13 and 15 carbon atoms of the present invention were able to completely prevent micro hydrophobic particles from floating on the water surface.

Claims (1)

[Scope of Claims] (1) A water-disintegrating granule comprising the following (1), (2)
) and (3) are uniformly mixed, or (1), (
A granule for weeding rice fields, which is obtained by uniformly mixing the substances 2), (3) and (4) and granulating the mixture by extrusion granulation. (1) Microscopic hydrophobic particles enclosing a sulfonylurea compound, (2) Calcium carbonate or inorganic mineral fine powder mainly composed of calcium carbonate, (3) General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (wherein R represents a linear or branched alkyl group having 11 to 20 carbon atoms, and X represents a hydrogen atom, a monovalent metal atom or an ammonium group) (4) One or more herbicidal active ingredients effective against barnyard grass, a rice field weed. (2) In the compound represented by the general formula [I], R represents a linear or branched alkyl group having 13 to 16 carbon atoms, and X represents an alkali metal atom. Granules for weeding rice fields. (3) The sulfonylurea compound is N-[(4,6-dimethoxypyrimidin-2-yl)aminocarbonyl]-4-ethoxycarbonyl-1-methylpyrazole-5-sulfonamide. Granules for weeding rice fields.