Wet milling assistant and aqueous slurry composition containing the same

Abstract

To provide a wet milling assistant that realizes excellent milling efficiency in wet milling, and in which an aqueous slurry composition obtained by wet milling has good flowability and low foamability.SOLUTION: A wet milling assistant of an organic compound contains an aromatic compound (A) and an aliphatic compound (B) at a prescribed ratio. The aromatic compound (A) is at least one selected from (alkyl) naphthalenesulfonic acid and a neutralization salt thereof. The aliphatic compound (B) is at least one of an ether compound (1) in which a total of 1 to 150 moles of alkylene oxide of carbon numbers 2 to 3 are added to 1 mole of an aliphatic monohydric alcohol of carbon numbers 3 to 16, and an ether compound (2) in which a total of 1 to 150 moles of alkylene oxide of carbon numbers 2 to 3 are added to 1 mole of an aliphatic dihydric alcohol of carbon numbers 2 to 14.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a wet grinding aid and an aqueous slurry composition containing the same. [Background technology]

[0002] One type of pesticide formulation known is an aqueous suspension (flowable formulation), in which pesticide active ingredients with low water solubility are wet-ground and uniformly dispersed in an aqueous medium. Aqueous suspensions are easy to measure and spray, and because they do not contain organic solvents, they have the advantage of eliminating the risk of workers inhaling vaporized organic solvents, and are therefore becoming one of the main types of pesticides.

[0003] Because agricultural chemicals are dispersed as solid particles in aqueous suspensions, the larger the particle size, the lower the biological efficacy. Therefore, it is desirable to maintain the particle size of agricultural chemicals in aqueous suspensions small, preferably in the submicron range. However, wet milling is a process of physically grinding solid particles, and grinding to a desired particle size, especially submicron size, typically requires a significant amount of work time and energy. Furthermore, because many agricultural chemicals are hydrophobic, the tendency for reagglomeration increases with decreasing particle size, making wet milling to submicron sizes difficult for some types of agricultural chemicals. To address these issues, various grinding aids have been proposed for wet milling of organic compounds such as pesticides.

[0004] For example, Patent Documents 1 to 8 disclose conventional grinding aids for wet grinding. Patent Document 1 discloses a grinding aid consisting of an alkylnaphthalenesulfonate salt of a specific structure. Patent Document 2 discloses a grinding aid consisting of a salt of a compound obtained by adding ethylene oxide, propylene oxide, or butylene oxide to an alcohol having 4 to 12 carbon atoms, esterifying the alcohol with a dicarboxylic acid anhydride, with or without adding ethylene oxide, propylene oxide, or butylene oxide, and then sulfonating the resulting alcohol. Patent Document 3 exemplifies grinding aids (dispersants) such as polyalkylene glycol ethers and condensation products of ethylene oxide, propylene oxide, or a mixture of ethylene oxide and propylene oxide with alkylphenols, aliphatic alcohols, aliphatic amines, or fatty acids. Patent Document 4 discloses a grinding aid consisting of a formaldehyde condensate of sodium alkylnaphthalenesulfonate and a polyoxyethylene-polyoxypropylene copolymer. Patent Document 5 discloses a grinding aid consisting of a formaldehyde condensate of sodium phenolsulfonate and a block copolymer of polyoxyethylene-polyoxypropylene. Patent Documents 6 and 7 exemplify alkylnaphthalenesulfonates as grinding aids. Patent Document 8 discloses a grinding aid consisting of a mixture containing the sodium salt of an alkylnaphthalenesulfonate-formaldehyde condensate.

[0005] Dry milling, which is one type of milling, is known to have the advantage of being able to suppress the inclusion of contaminants compared to wet milling, and is often used in the preparation of pharmaceutical compositions that require extremely high safety. Even in such dry milling, surfactants are sometimes used as milling aids (see, for example, Patent Document 9). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 2931603 [Patent Document 2] Patent No. 2750173 [Patent Document 3] Patent No. 6186370 [Patent Document 4] U.S. Patent Publication No. 2001 / 0051175 [Patent Document 5] Patent No. 4620923 [Patent Document 6] Japanese Patent Application Laid-Open No. 2003-238315 [Patent Document 7] Japanese Patent Application Publication No. 5-17303 [Patent Document 8] Patent Publication No. 2021-042200 [Patent Document 9] Patent No. 6460897 Summary of the Invention [Problem to be solved by the invention]

[0007] However, conventional wet-grinding aids may not be sufficient to reduce the size of organic compounds or to prevent re-agglomeration, making it impossible to achieve the desired particle size of the organic compounds, i.e., resulting in insufficient grinding efficiency. Furthermore, depending on the type of wet-grinding aid, the foaming property may be too high, resulting in a poor yield, or the organic compounds may aggregate while incorporating air and water during grinding, causing the suspension (slurry) to lose fluidity.

[0008] Therefore, an object of the present invention is to provide a wet-grinding aid that realizes excellent grinding efficiency in wet grinding and provides an aqueous slurry composition obtained by wet grinding that has good fluidity and low foaming properties, and an aqueous slurry composition containing the same. [Means for solving the problem]

[0009] The present invention takes the following measures to solve the above problems. [1] A wet-grinding aid for organic compounds, comprising the following aromatic compound (A) and the following aliphatic compound (B), wherein the aromatic compound (A) accounts for 10 to 99 mass% when the total content of the aromatic compound (A) and the aliphatic compound (B) is taken as 100 mass%. Aromatic compound (A): at least one selected from (alkyl)naphthalenesulfonic acids and their neutralized salts Aliphatic compound (B): at least one selected from the following ether compound (1) and the following ether compound (2): Ether compound (1): A compound in which a total of 1 to 150 moles of alkylene oxide having 2 to 3 carbon atoms are added to 1 mole of aliphatic monohydric alcohol having 3 to 16 carbon atoms. Ether compound (2): A compound in which a total of 1 to 150 moles of alkylene oxide having 2 to 3 carbon atoms are added to 1 mole of aliphatic dihydric alcohol having 2 to 14 carbon atoms. [2] The wet grinding aid according to [1], wherein the (alkyl)naphthalenesulfonic acid is an (alkyl)naphthalenesulfonic acid formed from 1 mole of naphthalenesulfonic acid and 0.7 to 3.0 moles of an aliphatic monohydric alcohol having 1 to 4 carbon atoms. [3] The wet grinding aid according to [1], wherein the aliphatic compound (B) is a compound selected from the ether compounds (1). [4] An aqueous slurry composition comprising the organic compound, any one of the wet grinding aids [1] to [3], and water. [5] The aqueous slurry composition of [4], containing the organic compound in an amount of 1 to 70 mass %, the wet-grinding aid in an amount of 0.1 to 10 mass %, and the water in an amount of 20 to 98.9 mass %, where the total content of the organic compound, the wet-grinding aid, and the water is 100 mass %.

[0010] In this specification, the numerical ranges indicated by "XX to △△" include the upper and lower limits. In other words, "XX to △△" means "greater than or equal to XX and less than or equal to △△." [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a wet-grinding aid that can achieve excellent grinding efficiency in wet grinding and an aqueous slurry composition containing the same, which has good fluidity and low foaming properties when obtained by wet grinding. DETAILED DESCRIPTION OF THE INVENTION

[0012] <Wet grinding aid> The wet-grinding aid of the present invention is a wet-grinding aid for organic compounds, and contains an aromatic compound (A) and an aliphatic compound (B). By adding the wet-grinding aid of the present invention during wet-grinding of organic compounds, as described below, an aqueous slurry composition can be obtained in which the particle size of the organic compounds is small and which has good fluidity and foamability.

[0013] <Aromatic compounds (A)> The aromatic compound (A) is at least one selected from (alkyl)naphthalenesulfonic acids and neutralized salts thereof.

[0014] (Alkyl)naphthalenesulfonic acid refers to naphthalenesulfonic acid or (poly)alkylnaphthalenesulfonic acid. (Poly)alkylnaphthalenesulfonic acids include monoalkylnaphthalenesulfonic acids such as methylnaphthalenesulfonic acid, ethylnaphthalenesulfonic acid, propylnaphthalenesulfonic acid, isopropylnaphthalenesulfonic acid, butylnaphthalenesulfonic acid, and isobutylnaphthalenesulfonic acid, and polyalkylnaphthalenesulfonic acids such as dimethylnaphthalenesulfonic acid, diethylnaphthalenesulfonic acid, dipropylnaphthalenesulfonic acid, dibutylnaphthalenesulfonic acid, tripropylnaphthalenesulfonic acid, and tetrapropylnaphthalenesulfonic acid. Furthermore, (alkyl)naphthalenesulfonic acids contain at least one of (alkyl)naphthalenemonosulfonic acid, (alkyl)naphthalenedisulfonic acid, and (alkyl)naphthalenetrisulfonic acid, depending on the degree of sulfonation. The alkyl group may be branched or linear.

[0015] The (alkyl)naphthalenesulfonic acid is preferably formed from 1 mole of naphthalenesulfonic acid and 0.7 to 3.0 moles of an aliphatic monohydric alcohol having 1 to 4 carbon atoms, and more preferably formed from 1 mole of naphthalenesulfonic acid and 0.7 to 3.0 moles of an aliphatic monohydric alcohol having 3 or 4 carbon atoms.

[0016] Examples of neutralized salts of (alkyl)naphthalenesulfonic acids include alkali metal salts, alkaline earth metal salts, ammonium salts, and amine salts. Of these, sodium salts, potassium salts, ammonium salts, diethanolamine salts, and triethanolamine salts are preferred, and sodium salts are most preferred.

[0017] <Aliphatic compound (B)> The aliphatic compound (B) is at least one selected from the ether compound (1) and the ether compound (2).

[0018] The ether compound (1) is a compound in which a total of 1 to 150 moles of alkylene oxide having 2 to 3 carbon atoms are added to 1 mole of aliphatic monohydric alcohol having 3 to 16 carbon atoms. Particularly preferred is a compound in which a total of 1 to 20 moles of alkylene oxide having 2 to 3 carbon atoms are added to 1 mole of aliphatic monohydric alcohol having 3 to 16 carbon atoms. Further preferred is a compound in which a total of 1 to 20 moles of alkylene oxide having 2 to 3 carbon atoms are added to 1 mole of aliphatic monohydric alcohol having 10 to 16 carbon atoms. The aliphatic monohydric alcohol having 3 to 16 carbon atoms may be a primary alcohol, a secondary alcohol, or a tertiary alcohol. Examples of aliphatic monohydric alcohols having 3 to 16 carbon atoms include propanol, isopropanol, butanol, pentanol, hexanol, dodecanol, tridecanol, isotridecanol, tetradecanol, pentadecanol, and hexadecanol.

[0019] The ether compound (2) is a compound in which a total of 1 to 150 moles of alkylene oxide having 2 to 3 carbon atoms are added to 1 mole of an aliphatic dihydric alcohol having 2 to 14 carbon atoms. Examples of the aliphatic dihydric alcohol having 2 to 14 carbon atoms include ethylene glycol, propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,10-decanediol, 1,12-dodecanediol, and 1,2-tetradecanediol.

[0020] When ethylene oxide and propylene oxide are added as alkylene oxides, the alkylene oxides may be block copolymerized or random copolymerized. In this specification, the number of moles of alkylene oxide added means the average number of moles added.

[0021] From the viewpoint of the efficiency of crushing organic compounds, the aliphatic compound (B) is preferably selected from the ether compounds (1).

[0022] <Content ratio> The wet grinding aid contains 10 to 99 mass% of the aromatic compound (A), preferably 30 to 99 mass%, when the total content of the aromatic compound (A) and the aliphatic compound (B) is 100 mass%.

[0023] <Organic compounds> The organic compounds to be used as the wet grinding aid are not particularly limited as long as they are insoluble in water or have low water solubility and are generally prepared as aqueous slurry compositions, and conventionally known compounds can be used.The organic compounds may be used alone or in combination of two or more.Examples of such organic compounds include the following pesticide active ingredients such as insecticides, fungicides, or herbicides.

[0024] Examples of insecticides include chromafenozide, pyrimidifen, lepimectin, indoxacarb, ethiprole, carbaryl, chlorantraniliprole, chlorfenapyr, chlorfluazuron, diafenthiuron, cyantraniliprole, diflubenzuron, tebufenozide, teflubenzuron, tolfenpyrad, fenpyroximate, buprofezin, furathiocarb, flufenoxuron, flubendiamide, hexaflumuron, benzoepin, metaflumizone, lufenuron, and salts thereof.

[0025] Examples of fungicides include carbendazim, tolprocarb, penthiopyrad, azoxystrobin, orysastrobin, carpropamid, captan, cyazofamid, diclocymet, diclomedine, dithianon, tiadinil, thifluzamide, famoxadone, fthalide, fluorimide, flutolanil, procymidone, pencycuron, and salts thereof.

[0026] Examples of herbicides include atrazine, oxaziclomefone, cafenstrole, quizalofop-ethyl, cumyluron, clomeprop, dymron, thenylchlor, bifenox, pyraclonil, pyrazoxyfen, pyriftalid, pyributicarb, pyrazosulfuron-ethyl, pyraflufen-ethyl, fenoxasulfone, fentrazamide, phenmedipham, flumioxazin, prodiamine, propyrisulfuron, bromobutide, bensulfuron-methyl, benzofenap, benzobicyclon, pentoxazone, and mefenacet.

[0027] <Aqueous slurry composition> The aqueous slurry composition contains an organic compound, a wet grinding aid, and water. The organic compound is preferably an agrochemically active ingredient as described above.

[0028] <Content ratio> The content ratios of the organic compound and the wet-grinding aid in the aqueous slurry composition can be set appropriately depending on the type of organic compound. When the total content of the organic compound, the wet-grinding aid, and the water is taken as 100% by mass, the aqueous slurry composition preferably contains 1 to 70% by mass of the organic compound, 0.1 to 10% by mass of the wet-grinding aid, and 20 to 98.9% by mass of water, and more preferably contains 10 to 70% by mass of the organic compound and 1.0 to 5.0% by mass of the wet-grinding aid.

[0029] <Additives> The aqueous slurry composition may contain additives such as organic solvents, surfactants, thickeners, pH adjusters, antifreeze agents, antifoaming agents, antifungal agents, salts, antioxidants, and UV absorbers, as needed, provided that the effects of the composition are not impaired. Examples of the surfactant include anionic, cationic, amphoteric, and nonionic surfactants. Examples of such surfactants include polyoxyalkylene aryl phenyl ethers, polyoxyalkylenated castor oil, sorbitan fatty acid esters, polyoxyalkylene sorbitan fatty acid esters, polyoxyethylene-polyoxypropylene block copolymers, alkyl polyglycosides, sucrose fatty acid esters, metal dialkyl sulfosuccinates, metal alkyl benzene sulfonates, metal alkyl naphthalene sulfonate condensates, polyoxyalkylene aryl phenyl ether phosphate esters, polyoxyalkylene aryl phenyl ether sulfate esters, alkyl sulfates, polycarboxylates, lignin sulfonates, alkylamine hydrochlorides, alkyl quaternary ammonium salts, alkyl betaines, and fatty acid esters, but are not limited thereto.

[0030] ≪Manufacturing method≫ The wet-grinding aid can be produced by mixing an aromatic compound (A) and an aliphatic compound (B) in a predetermined ratio. On the other hand, the aqueous slurry composition can be produced by mixing the wet-grinding aid, an organic compound, water, and any additives, and then wet-grinding the mixture using a paint shaker, sand mill, ball mill, Dyno Mill, Apex Mill, Attritor, or the like. Additives may be added after wet-grinding depending on the intended use. Wet-grinding may be carried out in a single step or in multiple steps, such as coarse grinding, medium grinding, fine grinding, and ultrafine grinding, depending on the type of organic compound and the particle size before and after grinding.

[0031] The wet-grinding aid of the present disclosure contains an aromatic compound (A) and an aliphatic compound (B) in a predetermined ratio, thereby achieving excellent grinding efficiency during wet grinding. Furthermore, the wet-grinded aqueous slurry composition has good fluidity and low foaming properties.

Example

[0032] Hereinafter, the structure and effects of the present disclosure will be described by way of specific examples and comparative examples. In the following examples and comparative examples, "part" means part by mass.

[0033] ≪Display of each component≫ Each component used in the examples and comparative examples is as follows.

[0034] <Component A: Aromatic compound>

Table 1

[0035] <Component B: Aliphatic compound>

Table 2

[0036] <Preparation Example 1> 87 parts of A-1 as the aromatic compound (A) and 13 parts of B-1 as the aliphatic compound (B) were mixed to obtain an auxiliary agent C-1 for wet grinding.

[0037] <Preparation Examples 2 to 21> Each auxiliary agent for wet grinding was obtained in the same manner as in Preparation Example 1, except that the types and blending amounts of the aromatic compound (A) and the aliphatic compound (B) were changed to the compositions shown in Table 3 below.

Table 3

[0038] <Example 1> 60 parts of atrazine as an organic compound, 2.5 parts of wet grinding aid C-1, 0.1 parts of silicone antifoaming agent as an additive, and 37.5 parts of city water were mixed, and then wet-ground using a paint shaker with 2 mm diameter zirconia beads for 30 minutes (coarse grinding step). The 2 mm diameter zirconia beads were removed from the resulting ground product, and 0.65 mm zirconia beads were added and wet-ground again (fine grinding step) to prepare an aqueous slurry composition. Then, only the aqueous slurry composition was collected using a 2 mm diameter dropper.

[0039] <Examples 2 to 13 and Comparative Examples 1 to 13> Each aqueous slurry composition was obtained in the same manner as in Example 1, except that the formulation of the aqueous slurry composition was changed to the constitution shown in Table 4 below.

[0040] [Table 4]

[0041] The aqueous slurry compositions of the Examples and Comparative Examples were subjected to the following tests, and the test results are shown in Table 4.

[0042] <Evaluation of viscosity and foaming properties> After the fine grinding step was carried out for 2 hours, the aqueous slurry composition was evaluated based on its viscosity and foamability. Foamability was evaluated by visually observing whether or not bubbles remained in the container after grinding. <Evaluation criteria> Good: No bubbles remain and the viscosity of the slurry is less than 800 mPas·s ×: Bubbles remain and / or the viscosity of the slurry is 800 mPa·s or more ××: Solidified and not fluid

[0043] <Crushing efficiency> The particle size (nm, median diameter) of the organic compound dispersed in the aqueous slurry composition after pulverization for 2 hours was measured using a laser diffraction / scattering particle size distribution analyzer (LA-960 manufactured by HORIBA, measurement solvent: ion-exchanged water). The evaluation criteria for pulverization efficiency are as follows: <Evaluation criteria> ◎◎: Less than 800nm ◎: 800nm ​​or more, less than 1000nm 〇: 1000nm or more, less than 1200nm ×: 1200nm or more -: Not evaluated because the aqueous slurry composition after grinding has no fluidity.

[0044] All of Examples 1 to 13 had good fluidity (viscosity) and low foamability, and also showed excellent grinding efficiency. On the other hand, in Comparative Examples 1 to 3, 9, 10, and 12, the wet-grinding aid did not contain an aromatic compound (A), so at least one of the fluidity and foamability was poor. In Comparative Examples 4 to 8, the wet-grinding aid did not contain an aliphatic compound (B), so the grinding efficiency was poor. In Comparative Examples 11 and 13, the content of the aromatic compound (A) in the wet-grinding aid was either excessive or insufficient, so the fluidity and foamability were poor.

Claims

1. A wet grinding aid for organic compounds, comprising: The composition contains the following aromatic compound (A) and the following aliphatic compound (B), A wet grinding aid characterized by containing 10 to 99 mass% of the aromatic compound (A) when the total content of the aromatic compound (A) and the aliphatic compound (B) is taken as 100 mass%. Aromatic compound (A): At least one selected from (alkyl)naphthalenesulfonic acids and their neutralized salts Aliphatic compound (B): at least one selected from the following ether compound (1) and the following ether compound (2): Ether compound (1): a compound in which a total of 1 to 150 moles of alkylene oxide having 2 to 3 carbon atoms are added to 1 mole of aliphatic monohydric alcohol having 3 to 16 carbon atoms. Ether compound (2): a compound in which a total of 1 to 150 moles of alkylene oxide having 2 to 3 carbon atoms are added to 1 mole of aliphatic dihydric alcohol having 2 to 14 carbon atoms.

2. 2. The wet grinding aid according to claim 1, wherein the (alkyl)naphthalenesulfonic acid is formed from 1 mole of naphthalenesulfonic acid and 0.7 to 3.0 moles of an aliphatic monohydric alcohol having 1 to 4 carbon atoms.

3. 2. The wet-grinding aid according to claim 1, wherein the aliphatic compound (B) is a compound selected from the ether compounds (1).

4. An aqueous slurry composition comprising the organic compound, the wet-grinding aid according to claim 1 , and water.

5. 5. The aqueous slurry composition according to claim 4, wherein the organic compound is contained in an amount of 1 to 70% by mass, the wet-grinding aid is contained in an amount of 0.1 to 10% by mass, and the water is contained in an amount of 20 to 98.9% by mass, where the total content of the organic compound, the wet-grinding aid, and the water is taken as 100% by mass.

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