JPH0733605A - Improved agrochemical emulsion composition - Google Patents

Abstract

PURPOSE:To provide the composition prevented from deposition of crystals during its preservation at low temperatures and from a spray prepared by diluting the composition with water. CONSTITUTION:The agrochemical emulsion composition containing, as active ingredient, at least one kind of phenylurea-based compound, and furthermore, containing (A) 5-60wt.%, based on 100wt.% of the final composition, of a low- polar solvent such as N-octyl-2-pyrrolidone and (B) 1-15wt.%, based on 100wt.% of the final composition, of a polar solvent such as N-methyl-2-pyrrolidone.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a pesticide emulsion composition containing at least one phenylurea compound as an active ingredient, and crystals from a formulation at low temperature during storage and from a spray solution diluted with water during use. The present invention relates to an agricultural chemical emulsion composition improved for the purpose of preventing precipitation.

[0002]

Agrochemical compositions containing phenylurea compounds as active ingredients are widely used, for example, as field-acting herbicides. There are wettable powders and emulsions in the form of the agricultural chemical compositions. Both are diluted with water and sprayed. Most of the phenylurea compounds are solid crystalline compounds at room temperature, and a high concentration wettable powder can be easily produced by finely pulverizing the compound.

However, the phenylurea compounds have poor solubility in organic solvents, and in particular, they are hardly soluble in hydrocarbon nonpolar solvents generally used for emulsions, and therefore it is very difficult to produce a high concentration emulsion. Therefore, a wettable powder is widely used as a form of an agricultural chemical composition containing a phenylurea compound as an active ingredient. However, since the expression of the herbicidal effect is superior to the wettable powder, the emulsion has been attempted for some time.

.. A method of dissolving an active ingredient in an alicyclic ketone (Japanese Patent Laid-Open No. 5069230/1975); A method of blending acetophenone and an aromatic solvent (Japanese Patent Publication No. 2-7282) is disclosed. However, while the method of (1) suppresses the precipitation of crystals during low-temperature storage, the crystals precipitate in the spray liquid diluted with water during use in a short time and cause clogging of the spray nozzle. Although it is quite effective in suppressing crystal precipitation in the environment, crystal precipitation is observed during storage at low temperature, and the peculiar odor of acetophenone is strong, and there is concern about safety for users.

Further, as a method for preventing the precipitation of crystals in the diluted spray solution, a method in which an alkylcarboxylic acid dimethylamide is used as a solvent in an emulsion containing an azo compound as an active ingredient (JP-A-4-225901). ) Is disclosed, the alkylcarboxylic acid dimethylamides are highly toxic and have a problem in terms of safety for users, and also have an insufficient solubility for phenylurea compounds.

[0006]

PROBLEM TO BE SOLVED BY THE INVENTION In an agricultural chemical emulsion composition containing at least one phenylurea compound as an active ingredient, it is necessary to prevent crystal precipitation in the preparation during low temperature storage and in the spray liquid diluted with water. However, an agricultural chemical emulsion composition that solves the above problems from the viewpoint of safety and physical properties has not been obtained.

[0007]

In view of the above situation, the inventors of the present invention have conducted extensive studies to solve the above problems, and as a result, in an agricultural chemical emulsion composition containing at least one phenylurea compound as an active ingredient. The present inventors have completed the present invention by finding that by reasonably blending a low-polarity solvent and a polar solvent, an excellent effect of preventing crystal precipitation, which cannot be predicted from conventional known techniques, can be obtained. That is, the present invention provides an agricultural chemical emulsion composition in which crystals do not precipitate during storage at low temperature and in a spray solution diluted with water.

Examples of the phenylurea compound to be added to the agricultural chemical emulsion composition as an active ingredient in the present invention include 3- (3,4-dichlorophenyl) -1-methoxy-1-methylurea (hereinafter referred to as compound A- 1) 3
-(3,4-Dichlorophenyl) -1,1-dimethylurea (hereinafter referred to as compound A-2), 3- (4-isopropylphenyl) -1,1-dimethylurea (hereinafter referred to as compound A-3), etc. These active ingredient compounds can be used alone or in admixture with other active ingredient compounds.For example, by mixing with a dinitroaniline compound, harmful weeds can be controlled very effectively. can do. Examples of these dinitroaniline compounds include N- (1-ethylpropyl)
-3,4-Dimethyl-2,6-dinitroaniline (hereinafter referred to as compound B-1), 2,6-dinitro-N, N
-Dipropyl-4-trifluoromethylaniline (hereinafter referred to as compound B-2) and the like can be exemplified.

[0009] The mixing ratio of these active ingredients is rationally selected so as not to cause phytotoxicity to the crop to which it is applied and to exert a sufficient herbicidal effect on weeds other than the crop, but it is usually. When the phenylurea compound is used alone to 100 parts by weight of the pesticide emulsion composition, it is 5 to 20 parts by weight, and when it is mixed with another active ingredient compound such as a dinitroaniline compound, the phenylurea compound is 5 to 5 parts by weight.
It may be appropriately selected and used from the range of 20 parts by weight and 10 to 30 parts by weight of the dinitroaniline compound.

Examples of the low-polarity solvent used in the present invention include N-octyl-2-pyrrolidone and N-dodecyl-2.
-Pyrrolidone, N-dodecylcaprolactam and the like can be exemplified, and as the polar solvent, for example, N-methyl-
2-pyrrolidone, cyclohexanone, N, N-dimethylformamide, dimethylsulfoxide and the like can be exemplified, and preferably N-octyl-2 is used as the low polar solvent.
-N-methyl-2-pyrrolidone can be exemplified as the pyrrolidone and the polar solvent. N as a low-polarity solvent
-Octyl-2-pyrrolidone and N- as polar solvent
Methyl-2-pyrrolidone is a 2-pyrrolidone derivative, is an organic solvent having low toxicity to humans and animals and causing no phytotoxicity to crops to which the agricultural chemical emulsion composition of the present invention is applied.

The mixing ratio of the low polar solvent and the polar solvent in the present invention is such that the mixed solvent of the low polar solvent and the polar solvent is mixed so as not to cause crystal precipitation in the preparation at -5 ° C, and diluted with water at the time of use. It is necessary to limit the compounding amount of the polar solvent in the spray solution for at least 24 hours so that crystal precipitation does not occur, and the ratio is 5 to 60 parts by weight of the low polar solvent to 100 parts by weight of the agrochemical emulsion composition, and 1 polar solvent
~ 15 parts by weight may be appropriately selected and used from the range,
Preferably, the low polar solvent is in the range of 5 to 30 parts by weight and the polar solvent is in the range of 1 to 10 parts by weight.

N-octyl-2-without the use of polar solvents
The use of only a low polarity solvent such as pyrrolidone requires a large amount of compounding to prevent crystal precipitation in the formulation during low temperature storage, and the pesticide emulsion composition is a spray solution diluted with water during use. Emulsification becomes poor. In order to solve this problem, a polar solvent such as N-methyl-2-pyrrolidone may be appropriately used in combination to reduce the low polar solvent, and the present invention requires the combined use of the low polar solvent and the polar solvent.

To produce the agricultural chemical emulsion composition of the present invention,
For example, in the case of mixing with a predetermined amount of phenylurea-based compound as an active ingredient, dinitroaniline-based compound and the like are mixed with a low polar solvent, a polar solvent, an emulsifier and a hydrocarbon-based non-polar solvent, and a conventional method for pesticide formulation Can be manufactured by. The type and amount of the emulsifier used in the present invention are not particularly limited, and include, for example, polyoxyalkylene alkylphenyl ether, polyoxyalkylene allyl phenyl ether, polyoxyalkylene allyl phenyl ether formaldehyde condensation. Examples thereof include polyoxyalkylene castor oil ether, polyoxyalkylene alkyl ether phosphate, polyoxyalkylene allyl phenyl ether phosphate, and alkylbenzene sulfonate, and these emulsifiers may be used alone or It can be mixed and used.

The hydrocarbon-based non-polar solvent is a solvent generally used in pesticide emulsion compositions, and examples thereof include xylene, kerosene, methylnaphthalene, Solvesso (manufactured by Exxon Chemical Co.) and the like. Further, if necessary, other organic solvent, stabilizer, dehydrating agent, and other components may be added.

[0015]

EXAMPLES Representative examples, comparative examples and test examples of the present invention are shown below, but the present invention is not limited to these. In the examples and comparative examples, “part” means “part by weight”.

Example 1 10.3 parts of A-1 drug substance (97%), emulsifier A (mixture of polyoxyalkylene allyl phenyl ether, polyoxyalkylene allyl phenyl ether condensate and calcium alkylbenzene sulfonate) 14.0 parts, N-
Octyl-2-pyrrolidone 10.0 parts, N-methyl-2
-Pyrrolidone 5.0 parts, Solvesso (# 200) 60.
7 parts were mixed and dissolved to obtain an emulsion containing 10% of A-1. Examples 2 to 13 In the same manner as in Example 1, pesticide emulsion compositions were obtained at the compounding ratios shown in Table 1.

[0017]

[Table 1]

[0018]

[Table 2]

[0019]

[Table 3]

Note: Emulsifier A A mixture of polyoxyalkylene allyl phenyl ether, polyoxyalkylene allyl phenyl ether condensate and calcium alkylbenzene sulfonate Emulsifier B Polyoxyalkylene phenyl phenol ether derivative and calcium alkyl benzene sulfonate Mixture of Emulsifier C Dodecylbenzenesulfonic acid Emulsifier D Polyoxyalkylene alkylphenyl ether
Mixture of calcium tellurite

Comparative Example 1 10.3 parts of A-1 drug substance (97%), emulsifier A14.0
Parts, N-methyl-2-pyrrolidone 15.0 parts and Solvesso (# 200) 60.7 parts are mixed and dissolved to prepare 10 parts of A-1.
An emulsion containing 10% was obtained. Comparative Examples 2 to 7 In the same manner as in Comparative Example 1, pesticide emulsion compositions were obtained at the compounding ratios shown in Table 2.

[0022]

[Table 4]

[0023]

[Table 5]

Test Example 1 Crystal Precipitation Test in Diluted Solution 100 ml Beaker was charged with 100 ml of 3 times hard water, 1.0 g of the pesticide emulsion prepared in Examples and Comparative Examples was added to the solution and stirred sufficiently. Mix and leave for 24 hours. Then, the diluted solution was passed through a sieve having openings of 45 μm, and the amount of crystals remaining on the sieve was visually determined according to the following criteria. Criteria −: No crystal ±: Very slight crystal +: Small amount of crystal ++: Large amount of crystal +++: Large amount of crystal The results are shown in Table 3.

Test Example 2 Crystallization Precipitation Test in Formulation 1 g of 5.0 g of the agricultural chemical emulsion prepared according to Examples and Comparative Examples was used.
Put in a 0 ml test tube, add a small amount of seed crystal, and add -5 ° C.
After standing for 7 days, the amount of precipitated crystals was visually determined according to the criteria of Test Example 1. The results are shown in Table 3.

[0026]

[Table 6]

[0027]

[Table 7]

As shown in Table 1, in an agricultural chemical emulsion composition containing at least one phenylurea compound of the present invention as an active ingredient, a low polar solvent such as N-octyl-2-pyrrolidone and N-methyl-2-pyrrolidone are used. The pesticide emulsion composition containing a polar solvent such as the above does not cause crystal precipitation either when used alone or when mixed with other pesticide active ingredients in the formulation during low-temperature storage or in the spray liquid diluted with water during use. That is clear.

Claims (4)

[Claims] 1. An agrochemical emulsion composition containing at least one phenylurea compound as an active ingredient, which comprises adding a low-polarity solvent and a polar solvent to prevent precipitation of crystals. 2. The pesticide emulsion composition according to claim 1, wherein the low-polarity solvent is N-octyl-2-pyrrolidone, N-dodecyl-2-pyrrolidone or N-dodecylcaprolactam. 3. The pesticide emulsion composition according to claim 1, wherein the polar solvent is N-methyl-2-pyrrolidone, cyclohexanone, N, N-dimethylformamide or dimethylsulfoxide. 4. The pesticide emulsion composition according to claim 2 or 3, wherein the low polar solvent is 5 to 60 wt% and the polar solvent is 1 to 15 wt% with respect to 100 wt% of the pesticide emulsion composition. .