JPS6334841B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an agrochemical powder composition that has extremely good fluidity and less scattering and flotation. In recent years, there has been an extremely high demand for agrochemical powders with low scattering and floating properties from the viewpoint of environmental pollution during agrochemical spraying, safety for workers, and medicinal efficacy. Generally, agrochemical powders must be uniformly dispersed, and for this purpose they need to have good fluidity. For this reason, a powder composition with improved fluidity can be obtained by adding an additive that improves fluidity, such as isopropyl phosphate, to a powder in which a pesticide active ingredient is adsorbed onto a mineral fine particle carrier. Although dispersibility and powder dispersion during spraying are improved, this usually results in an increase in scattering and flotation, and it is a very difficult problem to simultaneously improve fluidity and powder dispersion and reduce scattering and flotation. It was hot. However, from the viewpoint of safety as described above, there is a strong demand for a solution to this problem, and the industry is actively conducting studies to meet this demand. For example, liquid paraffin, polyalkylene glycol, phosphate ester anionic surfactant, 30
A sorbitan ester compound that is liquid at °C.
A proposal to use a mixture of isopropyl phosphate and a non-volatile liquid substance with a viscosity above a certain value as an additive, or a proposal to use a combination of a hydrophobic organic compound with a viscosity above a certain value and a carrier with a viscosity above a certain value etc. have been conventionally practiced. However, although these methods aim to both prevent scattering and improve fluidity of powder compositions, they do not utilize the caking effect of these oily substances by using all oily substances as additives. Therefore, there is a risk of making the powder sticky or reducing its fluidity. Therefore, in order to improve stickiness and fluidity, powder compositions using the above additives often use an auxiliary carrier with a high oil absorption capacity, such as white carbon, in combination with the additive, which is effective in improving these properties. . Furthermore, in order to place special emphasis on safety when using agricultural chemicals, it is now important to reduce the scattering and buoyancy of powder agents, and for this reason, the use of so-called classified carriers that suppress the content of fine particles below a certain amount has become popular. ing. However, in this case, while the scattering and flotation properties of the powder are reduced, the powder tends to become sticky and its fluidity tends to be reduced. This tendency is particularly pronounced in the case of powders that use liquid agricultural chemical ingredients and classified carriers, so the amount of white carbon and additives used increases. At present, it is difficult to simultaneously satisfy both anti-scattering properties and fluidity, and it is also economically expensive. In view of the above situation, the present inventors conducted intensive research with the aim of obtaining a pesticide powder with high scattering and floating resistance and high fluidity while reducing the use of additives that can be used regardless of the properties of the pesticide raw material. As a result, using an ester compound with a specific chemical structure as an additive,
The present invention has been completed based on the discovery that the above object can be achieved by using a classified carrier with a particle content of 5 microns or less of 10% by weight or less in an agrochemical powder. That is, the gist of the present invention is that an acyclic polyhydric alcohol having 3 or more hydroxyl groups and a total carbon number of 12 or less, and a linear or branched, saturated or unsaturated monohydric carboxylic acid having a total carbon number of 8 to 22. Fine particles containing 0.2 to 3% by weight of a single product or a mixture of two or more selected from the group of partial ester compounds having at least one hydroxyl group in the molecule obtained by reaction, and having a particle size of 5 microns or less. The present invention relates to an agrochemical powder composition characterized by using a mineral carrier for agrochemical powder having a content of 10% by weight or less. Specific examples of acyclic polyhydric alcohols having 3 or more hydroxyl groups and a total of 12 or less carbon atoms to be used as a raw material for the partial ester compound in the present invention include pentaerythritol, dipentaerythritol, trimethylolpropane, glycerin, diglycerin, etc. Can be mentioned. Although the present invention specifies that the polyhydric alcohol used is an acyclic alcohol, the partial ester compound in the present invention using the above-mentioned acyclic polyhydric alcohol is a cyclic polyhydric alcohol ester, such as higher fatty acid sorbitan. It has superior performance compared to esters and their ethylene oxide adducts, and particularly improves the fluidity of powder compositions. Further, specific examples of linear or branched, saturated or unsaturated monohydric carboxylic acids having a total carbon number of 8 to 22 used as raw materials for the partial ester compound in the present invention include n-octylic acid, iso-octylic acid, Examples include lauric acid, palmitic acid, oleic acid, n-stearic acid, iso-stearic acid, coconut oil fatty acid, beef tallow fatty acid, and rice bran fatty acid. As the compound in the present invention obtained by reacting the raw material alcohol and the raw material carboxylic acid, any compound having the chemical structure specified above can be used, but in particular, complete esters in which all hydroxyl groups are ester-bonded can be used. From the viewpoint of effectiveness, it is preferable to use a partial ester in which at least one hydroxyl group remains. Specific examples of the partial ester compound in the present invention include di-n-stearate pentaerythritol ester, mono-oleate pentaerythritol ester, di-laurate pentaerythritol ester, di-n-stearate dipentaerythritol ester, mono- n-stearate trimethylolpropane ester, di-tallow fatty acid trimethylolpropane ester, iso-octyl-n-stearate trimethylolpropane ester, di-n-stearate glycerin ester, tri-n-stearate trimethylolpropane ester etc. The partial ester compound in the present invention can be easily obtained by dehydrating and esterifying the raw material alcohol and the raw material carboxylic acid in the presence of an acidic or basic catalyst according to a conventional method. The amount of the partial ester compound used as an additive in the present invention is 0.2 to 3% by weight, preferably 0.5 to 2% by weight, based on the agricultural chemical powder, regardless of the properties and effects of the agricultural chemical raw material. If the amount added is less than 0.2% by weight, sufficient anti-scattering properties and fluidity will not be obtained, and if it is more than 3% by weight, the effect commensurate with the amount added will not be obtained. Moreover, if the additive of the partial ester compound in the present invention is selected according to the properties and action of the agricultural chemical raw material, it is possible to obtain a powder composition with good performance without adding white carbon at the above-mentioned addition amount. It is also possible to use an auxiliary carrier such as white carbon. Next, mineral carriers for agricultural chemical powders used in the present invention include clay, talc, kaolin, diatomaceous earth, etc.
Examples include powders in which the content of submicron particles is 10% by weight or less. In addition, in the present invention, conventional additives such as oils and fats,
Glycols, nonionic surfactants, phosphate anionic surfactants, phosphate compounds used as agricultural chemical stabilizers, and the like can be used in combination without impairing the effects of the present invention. The agrochemical powder composition of the present invention can be easily obtained by uniformly mixing the agrochemical raw material, a partial ester compound, a mineral carrier, and, if necessary, an auxiliary carrier by a conventional method for producing agrochemical powder compositions. If necessary, it can also be manufactured by a premix method. The mechanism of action by which the partial ester compound exhibits excellent performance as an additive in the agrochemical powder composition of the present invention is not well understood, but because it has a specific chemical structure, it has a caking effect that is different from that of conventional oil additives. It is thought that the properties such as lubricity and caking properties work together effectively on the powder, thereby improving both the anti-scattering and fluidity of the powder, which are contradictory properties. The agrochemical powder composition of the present invention and its effects will be explained below with reference to Examples, but the present invention is not limited thereto. Example 1 97 g of clay for agricultural chemical powders (hereinafter referred to as "Katsuto Clay") containing 10% by weight of fine particles of 5 microns or less as a carrier, 1 g of di-n-stearate trimethylolpropane ester as an additive, and 1 g of di-n-stearate trimethylolpropane ester as an agricultural chemical raw material that is solid at room temperature. 2 g of 1-naphthyl-N-methyl carbamate (hereinafter referred to as NAC) was placed in a small pulverizer and pulverized with stirring for about 90 seconds to obtain a uniform agrochemical powder composition of the present invention. Example 10 96 g of cut clay as a carrier, 1 g of di-n-stearic acid trimethylolpropane ester as an additive, and O, O-, which is liquid at room temperature as an agricultural chemical ingredient.
Dimethyl-O-(3-methyl-4-nitrophenyl) phosphorothioate (hereinafter referred to as MEP) 2
g. 1 g of white carbon as an auxiliary carrier is placed in a small pulverizer and pulverized with stirring for about 90 seconds to obtain a uniform agrochemical powder composition of the present invention. Examples 2 to 9, 11 to 17 and comparative examples 3, 4, 5,
8,9,10 The carriers, additives, agricultural chemical ingredients listed in Table 1, or auxiliary carriers are added thereto and stirred and ground in the same manner as in Example 1 or 10 to obtain a uniform agricultural chemical powder composition of the present invention or comparative example. get something Comparative Examples 1 and 6 The carriers and agricultural chemical ingredients listed in Table 1 were placed in a small pulverizer and agitated and pulverized for about 90 seconds. In Comparative Example 1, a uniform granule composition was obtained, but in Comparative Example 6, the powder obtained was so sticky that it could not be made into a product. Comparative Examples 2 and 7 The carrier, agricultural chemical raw material, and auxiliary carrier listed in Table 1 were placed in a small pulverizer and stirred for about 90 seconds to obtain a uniform agricultural chemical powder composition. The resulting agrochemical powder compositions of the present invention and comparative examples were measured for scattering buoyancy and fluidity during spraying using the following methods. Dispersion and Floatability Using a standard dust powder tester, spray 10g of the pesticide powder composition downward into a 1 m3 box, leave it for 5 minutes, and then remove the suspended particles at a position 40cm above the spray tube with water. Absorption was carried out for 1 minute at a flow rate of 30/min into an absorption tube containing 75 ml. To this suspension, 1 ml of a 6% aqueous solution of sodium dodecylbenzenesulfonate was added, and the transmittance at a layer length of 1 cm and a wavelength of 610 mμ was measured using a 0.08% aqueous solution of sodium dodecylbenzenesulfonate as a control. The scattering buoyancy was expressed using the buoyancy index shown below. The larger the buoyancy index is, the higher the buoyancy is. Fluidity: Put 50 g of the pesticide powder composition into a 16-mesh sieve (diameter 62 mm, height 33 mm), vibrate the sieve with a vibrator, and let it fall onto a top balance. Fluidity was expressed as the falling time (in seconds) until the powder reached 10 to 30 g. The shorter the falling time, the greater the fluidity. The measured results were as shown in Table 1 below.

【table】

[Table] The numbers in the column of pesticide powder composition represent the weight percent of each component in the pesticide powder composition.
○* Unable to measure due to stickiness of powder composition.
From the results shown in Table 1, it is clear that the agrochemical powder composition of the present invention has significantly lower scattering and flotation properties than the comparative examples, regardless of the properties of the agrochemical substance, and at the same time has extremely good fluidity. It is.

Claims (1)

[Claims] 1 Obtained by reacting an acyclic polyhydric alcohol having 3 or more hydroxyl groups and a total of 12 or less carbon atoms with a linear or branched, saturated or unsaturated monohydric carboxylic acid having a total of 8 to 22 carbon atoms. 0.2 to 3% by weight of a single product or a mixture of two or more selected from the group of partial ester compounds having at least one hydroxyl group in the molecule.
1. An agrochemical powder composition characterized by using a mineral carrier for an agrochemical powder, which contains a mineral carrier having a particle size of 5 microns or less in a content of 10% by weight or less.