JPH013101A - Aqueous suspension pesticide composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an aqueous suspension of agrochemical compositions, and more particularly, to an aqueous suspension of agricultural chemical compositions having a melting point of 15 to 15 to prevent crystal precipitation during storage.
The present invention relates to an aqueous suspension composition in which a water-insoluble physiologically active substance is stably dispersed at 70°C.

[Conventional technology and its problems]

Traditionally, water-insoluble biologically active substances as agricultural chemicals have been used as emulsions or wettable powders, but in recent years, suspensions (flowable formulations) in which fine particles of water-insoluble biocides are dispersed in water using an appropriate dispersant have been used. ) is now often used as Various anionic or nonionic surfactants or water-soluble polymeric surfactants have been proposed as dispersants, and stable suspension preparations have been obtained even under severe storage conditions.

However, as a water-insoluble physiologically active substance, the melting point is 15.
When using a product with a temperature of ~70°C, there was a problem in that if it was stored under conditions with a large temperature difference, crystal displacement occurred within the emulsified particles, causing emulsion breakage and crystal precipitation.

[Failure to solve the problem]

Therefore, the present inventors have proposed methods for stabilizing emulsions (suspensions): (1) enhancement of hydrophilic protective colloids through ionic complex formation, (2) improvement of hydrophilic protective colloids through hydrophobic/hydrophobic interactions, and (2) improvement of solubility parameters. As a result of various studies on methods such as surface modification using the bleed effect of slightly different substances, we found that by using phthalate ester in method (2) and using a specific dispersant, it is possible to achieve high temperature (50°C) and low temperature ( The present invention has been completed by discovering that a stable fluid suspension without emulsion destruction or crystal precipitation can be obtained even when stored under severe conditions such as a storage cycle test at -10°C.

That is, in the present invention, fine particles of a water-insoluble physiologically active substance having a melting point in the range of 15 to 70°C are mixed with a monomer selected from the group consisting of unsaturated carboxylic acids and derivatives thereof as a dispersant.
The present invention provides an aqueous suspension agricultural chemical composition that is stably dispersed using a water-soluble or water-dispersible polymer containing one or more seeds as essential components and a phthalate ester as a crystal precipitation inhibitor. .

The phthalic acid ester used in the present invention is an esterified product of phthalic acid and various alcohols.

The alcohol that forms an ester with phthalic acid is preferably a straight or branched chain alcohol having 4 to 22 carbon atoms.
Particularly preferred are alcohols having 10 to 18 carbon atoms. The phthalate ester may be either mono or diester, but diester is preferred.

The content of phthalate ester in the agricultural chemical composition of the present invention is preferably 0.01 to 1 in weight ratio to the physiologically active substance,
More preferably 0.05 to 0.8, more preferably 0.
It is 1 to 0.5.

The dispersant according to the present invention, that is, the water-soluble or water-dispersible polymer containing one or more 3M monomers as an essential component from the monomer group consisting of unsaturated carboxylic acids and derivatives thereof will be specifically explained.

Monomers used in the production of the polymer include unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid;
/Unsaturated dicarboxylic acids such as inic acid, derivatives thereof such as alkyl esters (such as methyl esters), alkali metal salts (such as soda salts), ammonium salts and organic amine salts (such as l-liethanolamine salts) of the above acids.
, there are mixtures of these. In addition to these monomers, copolymerizable monomers such as vinyl acetate, isobutylene, diisobutylene, and styrene can also be added as copolymerization components.

The method of polymerizing these monomers is conventionally known. Although there are no particular restrictions on the ratio of monomer components and the degree of polymerization of the polymer, it is necessary that the polymer be at least water-soluble or water-dispersible.

Specific examples include acrylic acid polymers, methacrylic acid polymers, copolymers of acrylic acid and methacrylic acid, copolymers of acrylic acid and methacrylic acid polyoxyethylene ester, acrylic acid and acrylic Copolymers of acid methyl ester, copolymers of acrylic acid and vinyl acetate, copolymers of itaconic acid and vinyl acetate or their saponified products, copolymers of acrylic acid and maleic acid, copolymers of maleic acid and isobutylene Examples include copolymers, copolymers of maleic acid and styrene, and salts of these with alkali metals, ammonia, and organic amines. Two or more of these polymers may be used in two phases.

The amount of the dispersant used in the present invention is preferably 0.001 to 1, more preferably 0.01 to 1 in weight ratio to the physiologically active substance.
05 to 0.5.

Specific examples of physiologically active substances used in the present invention include etofenpro, an insecticide.

x (m, p, 37 °C, 2-(4-ethoxyphenyl)-2-methylpropyl-3-phenoxyhensyl ether), dimeth x -1- (m, p, 52 °C, dimethyl-8- (N-methylcarhamoylmethyl)phosphorothiolthione-1.), phosalone (m, p, 48°C, S
-[(6-chloro-2-oxy-3-henduxadunyl)-methyl]diethylphosphorothiolthionate),
Supraside (m, p, 40℃, S-[5-methoxy-
For fungicides such as 2-oxo-2,3-dihydro-L3,4-thiadiazoyl-(3)-methyl]dimethylphosphorothiolthionate), binapacryl (m, p, 66°C, 2-secondary-butyl-4 , 6-sinitrophenyl-3-methylcrotonate), Fujiwan (m, p, 54"C.

For herbicides such as diisopropyl-1,3-dithiolane-2-colibunamalonate), phenothiol (m, p, 42°C, S-ethyl [(4-chloro-0-tolyl)oxycutioacetate, alachlor ( m, p, 41°C, 2-chloro-
2',6'-diethyl-N-methoxymethylacetanilide), trifluralin (m, p, 49°C, α, α.

Examples of acaricides include dymite (m, p, 70°C, 1.
1-bis(p-chlorophenyl)ethanol).

These physiologically active substances are present in the aqueous suspension agricultural chemical composition of the present invention in an amount of 10 to 60% by weight.

Other anionic or nonionic surfactants may be added to the aqueous suspension agricultural chemical composition of the present invention.

Examples of nonionic or anionic surfactants include polyalkylene oxide nonionic surfactants such as polyoxyalkylene alkyl ether and polyoxyalkylene alkylaryl ether, and alkyl sulfates, polyoxyalkylene alkyl sulfates, and Examples include anionic surfactants such as oxyalkylene alkyl phosphate ester salts.

The aqueous suspension agricultural chemical composition of the present invention usually has a melting point of 15 to 70.
It is obtained by heating and melting a mixture of a physiologically active substance and a phthalate ester at a temperature of 5 to 20 °C, and adding the mixture to an aqueous solution containing a dispersant while stirring with a homomixer.
A suspension having a particle size of approximately μ is obtained.

[Action and effect of invention]

In the aqueous suspension of the agricultural chemical composition of the present invention, the phthalate ester bleeds onto the surface of the physiologically active substance, thereby modifying the surface of the physiologically active substance, thereby making it possible to obtain an emulsion with excellent storage stability.

〔Example〕

The present invention will be described below with reference to Examples, but the present invention is not limited to these Examples. The phthalate esters and physiologically active substances used in the examples are listed below.

(1) Phthalate ester Compound (1) O Compound (2) 0 Compound (31CH3 o (CH2)S 0 (CL)s C.I.

Compound (4) 0 (ii > Physiologically active substance Physiologically active substance (1) Etofenbrosox (Kawa, p.
, 37℃) Physiologically active substance (n) Alachlor (+n, p, 41
°C) Physiologically active substances (■) Trifluralin (m, p, 49
C) Example 1 5 parts by weight of compound (1) and 30 parts by weight of physiologically active substance (1) were mixed and melted. 2 parts by weight of a sodium salt of a copolymer of itaconic acid and vinyl acetate (molar ratio 1/1) was dissolved in advance in 63 parts by weight of water, and the above mixed melt was gradually added to the solution while stirring with a homomixer. A suspension preparation was obtained.

Comparative Example 1 2 parts by weight of Nozukawa Lium salt, a copolymer of itaconic acid and vinyl acetate, was dissolved in 68 parts of water in advance, and 30 parts by weight of the physiologically active substance (T) was melted in a homomixer. The mixture was gradually added while stirring to obtain a suspension preparation.

Example 2 2 parts by weight of compound (2) and 20 parts by weight of physiologically active substance (T) were mixed and melted. In advance, 1 part by weight of a copolymer of styrene and maleic acid (molar ratio, 10.1.) was dissolved in 76 parts by weight of water, and the above mixed melt was gradually stirred with a homomixer. A suspension preparation was obtained.

Example 3 Compound [3) 10 parts by weight and biocide physiologically active substance (n) 3
0 parts by weight were mixed and melted. In advance, 1.0 parts by weight of a saponified product of a copolymer of acrylic acid and vinyl acetate (molar ratio I/1), polyoxyethylene (5 mol), and 0.5 parts by weight of sodium lauryl sulfate were added to 58.5 parts by weight of water. The above-mentioned mixed melt was gradually added into the melt while stirring with a homomixer to obtain a suspension preparation.

Example 4 Compound (4+ 15 parts by weight and physiologically active substance (I'1l)
30 multi-layered parts were mixed and melted. 1 part by weight of sodium polyacrylate was suspended in 54 parts by weight of water in advance, and the molten mixture described in 2 was gradually added to the mixture while stirring with a homomixer to obtain a suspension preparation.

Comparative Example 2 A physiologically active substance (TIT) was added to a cloth in which 1 part by weight of a 60% saponified vinyl acetate polymer was suspended in 69 parts by weight of water.
30 parts by weight of the melt was gradually added to the mixture with stirring using a homomixer to obtain a suspension preparation.

Comparative Example 3 Compound + 4) 1.5 parts by weight and physiologically active substance (IIT)
30 parts by weight were mixed and melted. 1 part by weight of sodium dodecylbenzenesulfonate and 2 parts by weight of phenylnityl polyethylene (12) styrenide were dissolved in 52 parts by weight of water in advance, and the above mixed melt was gradually added while stirring with a homomixer. A suspension preparation was obtained.

Test Example 1 A storage test was conducted on the suspension preparations prepared in Examples 1 to 4 and Company Comparative Examples 1 to 2, with one cycle of storage at -10°C for 3 days and 3 days at 50°C, and the particle size after oral administration was Changes in diameter, viscosity, presence or absence of crystal precipitation, changes in active ingredients, and changes in suspension stability were investigated using the following methods.

The results are shown in Table 1.

(Measuring method) Particle size (μ): Measured with a Coulter counter.

Viscosity (cps) - Measured with a B-type viscometer (30 rpm/2
5℃) Crystal precipitation (presence or absence)...Observation with an optical microscope (x
400) Change in active ingredient (%): Measured by gas chromatography Suspension stability (%): Place in a cylinder with an inner diameter of 2 cm and a height of 10 cm, and determine the suspension ratio using the following formula.

Claims (1)

[Claims] 1. Fine particles of a water-insoluble physiologically active substance having a melting point in the range of 15 to 70°C are used as a dispersing agent of one or two monomers selected from the monomer group consisting of unsaturated carboxylic acids and derivatives thereof. An aqueous suspension agricultural chemical composition obtained by stably dispersing a water-soluble or water-dispersible polymer containing the above as essential components and a phthalate ester as a crystal precipitation inhibitor. 2 The weight ratio of the dispersant to the physiologically active substance is 0.001~
1. The aqueous aqueous suspension agricultural chemical composition according to claim 1, comprising: 3 The weight ratio of phthalate ester to physiologically active substance is 0.
．． 2. The aqueous suspension agricultural chemical composition according to claim 1, wherein the aqueous suspension agricultural chemical composition contains the compound in a proportion of 0.01 to 1.