JPS6137702A - Preparation of agricultural chemical emulsion having improved preservation quality and emulsifiablity - Google Patents

Abstract

PURPOSE:To obtain an agricultural chemical emulsion having improved preservation quality and emulsifiability, by adding an ethylene oxide or propylene oxide adduct in a specific amount to an agricultural emulsion to prevent the change in appearance during preservation of the emulsion and improve the emulsification performance. CONSTITUTION:An agricultural chemical emulsion is formulated. In the process, one or more ethylene oxide or propylene oxide adducts of an allyl derivative expressed by the formula (R1 is H, <=12C alkyl, phenyl, styryl or benzyl; R2 is H or CH3; n is 1, 2 or 3; m is an integer 1-5) in an amount of 0.5-5wt% are added to the above-mentioned emulsion to prevent the change in appearance (deposition of crystals, formation of sediment produced on the surface of the emulsion, coloration, etc.) and promote powerfully the stability and improve the emulsion stability of the above-mentioned emulsion.

Description

[Detailed Description of the Invention] Pesticide emulsions are generally organic solvent solutions (hereinafter referred to as stock solutions) obtained by diluting agrochemical ingredients (active ingredients) that are poorly soluble in water in an organic solvent such as xylene, naphtha, methanol, or kerosene. This stock solution is prepared by adding an auxiliary agent, ie, an emulsifier, to emulsify it in water when spraying agricultural chemicals.

When selecting an emulsifier, it is important to consider the chemical and physical properties of the pesticide active ingredient so that it does not cause decomposition of the active ingredient or change in the appearance of the emulsion (coloring, precipitation of crystals, etc.) during storage of the emulsion. .

In addition, emulsifiers are used to adjust the water quality (temperature, hardness, etc.) of the dilution water used when preparing the spray solution, physical properties such as penetration and spreading power of the spray solution to increase the efficacy of the drug, and concentration of the emulsion. Although the emulsifier is selected with due consideration, it is usually prepared by blending a nonionic surfactant and an anionic surfactant. Examples of emulsifiers for these agricultural chemical formulations include conventional compounds. Examples of nonionic surfactants include polyoxyethylene [number of moles of ethylene oxide (hereinafter abbreviated as EO) 4 to 20 moles] nonylphenyl ether, polyoxyethylene (EOIO ~ 50 moles)
Castor oil ether, polyoxyethylene (E0
10 to 30 mol) formalin feedstocks such as styryl phenyl ether or hakore, polyoxyethylene (Eol.

-J50 mol) and sorbitan alkylates (laurate, stearate, oleate, etc.).

Examples of anionic surfactants include dodecylbenzene sulfonate (sodium salt, calcium salt, various amine salts, etc.) and dioctyl sulfozaccine. Nonionic surfactants provide the basic emulsifying power of emulsions ( It is involved in improving the physical properties of emulsions (particularly polyoxyethylene nonylphenyl ether surfactants) and polyoxyethylene castor oil ether surfactants (especially polyoxyethylene nonylphenyl ether surfactants).

On the other hand, anionic surfactants appropriately adjust the required HLB of the emulsion and contribute to stabilizing the emulsion.

However, it is known that excessive use of anionic surfactants may cause decomposition of the agricultural chemical substance or change in the appearance of the emulsion), and this is especially true for chemically unstable organic pesticides. Stabilizers are also used in emulsions. For example, there are Japanese Patent Publication No. 48-43860, Japanese Patent Publication No. 55-37967, and Japanese Patent Application Laid-Open No. 54-98334.

However, depending on the agricultural chemical component, it is often not possible to obtain sufficient emulsifying performance just by selecting an emulsifier, and a solution to this problem has been sought.

By adding 0.5 to 5% of oxide additives to the emulsion, it is possible to prevent changes in appearance during storage of the emulsion, such as precipitation of crystals and the formation of "stain" that occurs on the surface of the emulsion, and also to prevent coloring, etc. The present invention was completed by discovering that it has a preventive effect and strongly promotes the stability of emulsions of agricultural chemicals.

That is, the present invention relates to a method for producing an agrochemical emulsion with good storage stability and emulsifying property, which prevents one or more types of ethylene oxide or propylene oxide adducts of an allyl derivative represented by the general formula and has improved emulsifying performance. .

The ethoxylate of the allyl derivative represented by the above general formula of the present invention is, for example, phenylcellosolve.

Nonylphenyl ethoxylate [ethylene oxylate]”
(hereinafter abbreviated as EO)], nonylphenylpropoxylate [propylene oxide (hereinafter abbreviated as PO) 1 mol), p-tertbutylphenol ethoxylate) (B
OI mol), O-phenylphenolproboxylene)
(PO2 mol), distyrylphenol ethoxylate (802 mol), tristyrylphenol ethoxylate (Fli0 3 mol), etc., but are not limited thereto.

In addition, the agricultural chemicals according to the present invention include organic detergents; for example, 3
-Jethoxyphosphorylthiomethyl-6-chlorobenzoxazolone (phosalone), dimethyldicarpetoxyethyldithiophosphate (malathion) dimethyl-P-
Quanophenylthiophosphate ((methylthio)phenylcothiophosphate (fenthion), 0-ethyl-8,S-diphenyldithiophosphate (nidifenphos), carbame) Agents: e.g., tba2-secondarybutylphenyl-N-methyl Carbamate (Bassa), 1-naphthyl-N-methylcarbamate (NAC)
), S-(2-chlorobenzyl)N, N-diethylthiocarbamate (orthohencarb), 3-methoxycarbonylaminophenyl-N(3/-methylphenyl)carbamate (phenmedipham), pyrethroids:
Examples include, but are not limited to, evapyrethrin, phenothrin, permethrin, and fuenvalerate.

The emulsifier used in formulation is one that is commonly used in emulsions of good drugs, and the nonionic surfactant is polyoxyethylene (EOIO - 30 mol) styryl (or hahenzyl) phenyl (or haphenylphenyl) ether. ,
Polyoxyethylene (Eo 4-20 mol) Alkylphenyl ether, Polyoxyethylene (Eo 10-50
Mol) Castor oil ether, polyoxyethylene-alpha fatty acid ester.

Examples include polyoxyethylene E:C)-4 & sorbitan alkylate.

Typical anionic surfactants include dodecylbenzenesulfonic acid calcium salt and salts of various amines. These surfactants are blended to provide optimal natural emulsifying properties and emulsion stability.

It is sufficient to add the chemical substances of the present invention in an amount of 0.5 to 5 in the emulsion, but an appropriate usage rate is selected depending on the purpose.

Further, it is also possible to use a stabilizer in combination if necessary.

Although the mechanism by which the chemical substance of the present invention prevents crystal precipitation and the formation of "Oshi" is not clear, it is thought that nonionic surface activity is inhibited.

A manufacturing method for improving emulsion stability by improving the emulsion stability is described in the report of Japanese Patent Publication No. 46-6438, but in general, the addition of such lower alcohols is particularly easy to hydrolyze to the organic compound. It cannot be said that it is preferable. Furthermore, it is often observed that such emulsions undergo discoloration and precipitation during long-term storage.

On the other hand, the substance of the present invention is an ethoxylate of an allyl derivative having an ether bond in its structure, and can be said to be a completely new invention.

Next, examples according to the present invention will be given.

Example (1) Precipitation of crystals 9 Effect of preventing coloration A Cyanox emulsion with the following formulation was stored in a thermostat at 50° C. Precipitation of crystals 2 The presence or absence of coloration was visually observed.

*The emulsifier is polyoxyethylene (30 moles of Be, 75% castor oil ether, 25% calcium dodecylbenzenesulfonate) *The stabilizer is polyoxyethylene (9 moles of EO), nonylphenyl, using the following: Ether Phosphate Results Example ■ Effect on Preventing Crystal Precipitation A high-concentration fenitrothion emulsion with the following formulation was stored in a thermostat at 50°C, and the presence or absence of crystal precipitation was visually observed.

*The following emulsifiers were used.

Polyoxyethylene (EO average 30 mol) Castor oil ether 70% Calcium salt of dodecylbenzenesulfonate 30 pieces Example ■ Emulsifying performance test Observe the initial emulsifying property and stability after 1 hour in a 1000 times emulsion of the emulsion with the following formulation. did.

*The following emulsifiers were used: polyoxyethylene (gozo) sorbitan monooleate 50 thifolioxyethylene (EO 10 mol) nonylphenyl ether 20% dodecylbenzenesulfonic acid calcium salt 30% Results C: Poor C: Results better than precipitation It can be seen that the agricultural chemical emulsion produced according to the present invention has excellent storage stability and good emulsifying properties.

Claims (1)

[Claims] When formulating an agrochemical emulsion, there are the following general formulas ▲ mathematical formulas, chemical formulas, tables, etc. In addition, R_2 represents a hydrogen atom or a methyl group, n is an integer of 1 to 3, or m is 1
Indicates an integer between ~5. ) Addition of 0.5 to 5% of one or more ethylene oxide or propylene oxide additives of allyl derivatives represented by A method for producing a pesticide emulsion with good storage stability and emulsifying properties that prevents precipitation, etc.) and improves emulsifying performance.