Inorganic ultrafine particle slurry particle size control agent and inorganic ultrafine particle slurry

Abstract

The present invention aims to provide a particle size control agent for inorganic ultrafine particle slurry capable of controlling the volume average particle diameter (D50, dynamic light scattering method) of inorganic ultrafine particles in inorganic ultrafine particle slurry to 100 nm or less. The present invention is a particle size control agent for inorganic ultrafine particle slurry characterized by comprising a salt (B) of a hydroxycarboxylic acid having 2 to 7 carbon atoms and ammonia or an organic amine having 1 to 14 carbon atoms. The salt (B) is preferably composed of 100 mol of the hydroxycarboxylic acid and 50 to 350 mol of ammonia or the organic amine.

Description

Technical Field

[0001] This invention relates to particle size control agents for inorganic ultrafine particle slurries and inorganic ultrafine particle slurries. Background Technology

[0002] Inorganic microparticle slurries are widely used in coatings, ceramics, inks, etc. In recent years, with the aim of improving performance (such as surface roughness improvement), it is hoped that the volume average particle size (D50, dynamic light scattering method) of inorganic ultrafine particles in inorganic microparticle slurries can be controlled below 100nm. Summary of the Invention

[0003] The problem that the invention aims to solve

[0004] However, methods and particle size control agents for controlling the volume average particle size (D50, dynamic light scattering method) of inorganic ultrafine particles in inorganic ultrafine particle slurries to below 100 nm are not yet known. The object of this invention is to provide a particle size control agent for inorganic ultrafine particle slurries capable of controlling the volume average particle size (D50, dynamic light scattering method) of inorganic ultrafine particles in inorganic ultrafine particle slurries to below 100 nm.

[0005] Methods for solving problems

[0006] The particle size control agent for inorganic ultrafine slurry of the present invention is characterized in that it is composed of a salt (B) of a hydroxycarboxylic acid having 2 to 7 carbon atoms and an ammonia or an organic amine having 1 to 14 carbon atoms.

[0007] The inorganic ultrafine particle slurry of the present invention is characterized in that it contains the above-mentioned particle size control agent for inorganic ultrafine particle slurry, inorganic ultrafine particles (A) and water (C).

[0008] The volume average particle size (D50, dynamic light scattering method) of the inorganic ultrafine particles (A) in the slurry is less than 100 nm.

[0009] The manufacturing method of the present invention is characterized by being a method for manufacturing the above-mentioned inorganic ultrafine particle slurry.

[0010] It is prepared by rotating beads and discs with a diameter of 0.01 to 1 mm.

[0011] Invention Effects

[0012] The particle size control agent for inorganic ultrafine particle slurry of the present invention can easily control the volume average particle size (D50, dynamic light scattering method) of inorganic ultrafine particles in inorganic ultrafine particle slurry to below 100 nm.

[0013] Since the inorganic ultrafine particle slurry of the present invention contains the above-mentioned particle size control agent for inorganic ultrafine particle slurry, the volume average particle size (D50, dynamic light scattering method) of inorganic ultrafine particles in the inorganic ultrafine particle slurry can be easily controlled to below 100 nm, and the performance (such as improving surface roughness) can be easily improved in the fields of coatings, ceramics, inks, etc.

[0014] According to the manufacturing method of the present invention, since the above-mentioned particle size control agent for inorganic ultrafine slurry is used, it is possible to easily prepare inorganic ultrafine slurry with an inorganic ultrafine particle volume average particle size (D50, dynamic light scattering method) of less than 100 nm. Detailed Implementation

[0015] Examples of hydroxycarboxylic acids with 2 to 7 carbon atoms include monohydroxy monocarboxylic acids (glycolic acid, lactic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, γ-hydroxybutyric acid, and L-leucine, etc.), monohydroxy dicarboxylic acids (malic acid, propanedioic acid, and citric acid, etc.), monohydroxy tricarboxylic acids (citric acid and isocitrate, etc.), dihydroxy monocarboxylic acids (glyceric acid, mevalonic acid, and pantothenic acid, etc.), dihydroxy dicarboxylic acids (tartaric acid, etc.), pentahydroxy monocarboxylic acids (gluconic acid, etc.), and tetrahydroxy monocarboxylic acids (glucoheponic acid, etc.). From the viewpoint of easily controlling the volume average particle size (D50, dynamic light scattering method) of inorganic ultrafine particles in inorganic ultrafine slurries to below 100 nm, monohydroxy monocarboxylic acids, monohydroxy dicarboxylic acids, monohydroxy tricarboxylic acids, dihydroxy dicarboxylic acids, and pentahydroxy monocarboxylic acids are preferred.

[0016] Ammonia or organic amines with 1 to 14 carbon atoms, where ammonia refers to inorganic ammonia (NH3), can be categorized as monoamines (monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, tert-butylamine, pyrrolidine, pyridine, monohydroxy monoamines (monoethanolamine, N-methylethanolamine, dimethylaminoethanol, 2-amino-2-methyl-1-propanol, 1-amino-2-methyl-2-propanol, DL-isopropanolamine and propanolamine, etc.), and dihydroxy monoamines (diethanolamine and methyldiethanolamine). The inorganic ultrafine particles include amines (e.g., trihydroxy monoamines, triethanolamine, etc.) and pentahydroxy monoamines (e.g., D-glucosamine, N-methyl-D(-)-glucosamine, and N-n-octyl-D-glucosamine), diamines (e.g., ethylenediamine, putrescine (tetramethylenediamine), cadaverine (pentamethylenediamine), hexamethylenediamine, dimethylaminopropylamine, norbornenediamine, N,N-dimethyltrimethylenediamine, 1,3-diaminomethylcyclohexane, and piperazine), and triamines (e.g., diethylenetriamine, pentamethyldiethylenetriamine, and dipropyltriamine). From the viewpoint of easily controlling the volume average particle size (D50, dynamic light scattering method) of inorganic ultrafine particles in the inorganic ultrafine particle slurry to below 100 nm, ammonia and monoamines are preferred, more preferably ammonia, monohydroxy monoamine, dihydroxy monoamine, and trihydroxy monoamine, and particularly preferably ammonia, monohydroxy monoamine, and dihydroxy monoamine.

[0017] Salt (B) is preferably composed of 100 moles of hydroxycarboxylic acid and 50 to 350 moles of ammonia or organic amine (preferably 100 to 330, more preferably 160 to 300). If it is within this range, it is easier to control the volume average particle size (D50, dynamic light scattering method) of inorganic ultrafine particles in the inorganic ultrafine particle slurry to below 100 nm.

[0018] The inorganic ultrafine particle size control agent for slurries of the present invention can be manufactured by neutralization in a solvent (water, lower alcohols, etc.) capable of dissolving hydroxycarboxylic acids with 2 to 7 carbon atoms and ammonia or organic amines with 1 to 14 carbon atoms. The solvent can be removed (by filtration, distillation, etc.) after the preparation of salt (B), or it can be used directly. Furthermore, the inorganic ultrafine particle size control agent for slurries of the present invention can be used after dilution with water. The concentration is not particularly limited, but is preferably 20 to 60% by weight (water concentration: 40 to 80% by weight). Water, as described later, is preferred.

[0019] As an inorganic ultrafine particle size control agent applicable to the present invention, there are no limitations on the inorganic ultrafine particles that are mixed with water in the manufacturing process of coatings, dielectrics, inks, ceramics, etc. (including intermediates and final products), including metal oxides, metal hydroxides and metal carbonates.

[0020] Examples of metal oxides include titanium dioxide, zinc oxide, aluminum oxide, iron oxide, magnesium oxide, silicon dioxide, zirconium oxide, and boehmite.

[0021] Examples of metal hydroxides include aluminum hydroxide, magnesium hydroxide, calcium hydroxide, and iron hydroxide.

[0022] Examples of metallic carbonates include calcium carbonate, barium carbonate, and magnesium carbonate.

[0023] From the viewpoint that the volume average particle size (D50, dynamic light scattering method) of inorganic ultrafine particles in inorganic ultrafine particle slurry can be easily controlled to below 100 nm, metal oxides are preferred.

[0024] As the inorganic ultrafine particles (A) contained in the inorganic ultrafine particle slurry of the present invention, the aforementioned inorganic ultrafine particles can be used, and the preferred range is as described above. Furthermore, the aforementioned particle size control agent can be used as the particle size control agent, and the preferred range is as described above. As for water (C), examples include tap water, ion-exchanged water, distilled water, A1 to A3 (pure water) as specified in JIS K0557:1998 "Water used in tests of water and wastewater", and A4 (ultrapure water) as specified in JIS K0557:1998, among which ion-exchanged water, distilled water, A1 to A3 (pure water) as specified in JIS K0557:1998 and A4 (ultrapure water) as specified in JIS K0557:1998 are preferred.

[0025] The volume average particle size (nm, D50, dynamic light scattering method) of the inorganic ultrafine particles (A) in the slurry is preferably below 100, and more preferably below 50. It should be noted that the measurement limit of the particle size (nm, dynamic light scattering method) is about 0.1 nm.

[0026] Volume average particle size refers to the particle size measured at 25°C using a nanoparticle analysis apparatus (e.g., nanoPartica SZ-100, Horiba Ltd.) according to JIS Z8828:2019 "Particle size analysis - Dynamic light scattering (DLS)" (corresponding international standard: ISO 22412:2017, Particle size analysis - Dynamic light scattering (DLS) (IDT)). Volume average particle size (D50, Dynamic light scattering) refers to the particle size representing the 50% cumulative value of the cumulative distribution curve, i.e., the median particle size (D50, Dynamic light scattering).

[0027] In the inorganic ultrafine particle slurry of the present invention, the content of the particle size control agent is preferably 5 to 50 parts by weight relative to 100 parts by weight of inorganic ultrafine particles (A), more preferably 8 to 30 parts by weight, and particularly preferably 10 to 20 parts by weight. If it is within this range, it is easier to control the volume average particle size (D50, dynamic light scattering method) of the inorganic ultrafine particles in the inorganic ultrafine particle slurry to below 100 nm.

[0028] In addition to inorganic ultrafine particles (A), particle size control agent, and water (C), the inorganic ultrafine particle slurry of the present invention may contain known additives, etc., within a range that does not hinder the effects of the present invention. Examples of additives include defoamers, dispersants, thickeners, wetting agents, and surface treatment agents.

[0029] As for the rotary processing apparatus that can be used in the method for manufacturing inorganic ultrafine particle slurry of the present invention, any rotary processing apparatus that uses beads and discs can be used, such as tower mills, ball mills, sand mills, pearl mills, and bead mills.

[0030] The diameter of the beads is preferably 0.01 to 1 mm, and more preferably 0.1 to 0.2 mm. If it is within this range, it is easier to control the volume average particle size (D50, dynamic light scattering method) of the inorganic ultrafine particles in the inorganic ultrafine particle slurry to below 100 nm.

[0031] There are no particular restrictions on the material of the beads; examples include glass and zirconium oxide. Zirconia is preferred.

[0032] Example

[0033] Unless otherwise specified, “parts” refers to parts by weight and “%” refers to weight.

[0034] <Example 1>

[0035] 10,179 parts (100 moles of lactic acid) of lactic acid (reagent grade, containing 11.5% water, Fujifilm and Kojun Pharmaceutical Co., Ltd.) (b11), 3,036 parts (50 moles of ammonia) of 28% ammonia (b21) aqueous solution (Nacalai Standard Grade 1, Nacalai Tesque Co., Ltd.) and 11,431 parts of water were uniformly mixed to obtain an aqueous solution containing the particle size control agent of the present invention (B1; 40% concentration ammonium lactate aqueous solution).

[0036] <Example 2>

[0037] 39,232 parts (100 moles of gluconic acid) of gluconic acid (b12) aqueous solution (50%, Fujifilm and Koh Genuine Chemicals Co., Ltd.), 8,914 parts (100 moles) of dimethylaminoethanol (b22) (purity >99.0%, Tokyo Chemical Industry Co., Ltd.), and 23,179 parts of water were uniformly mixed to obtain an aqueous solution (B2; 40% aqueous solution of dimethylaminoethanol gluconic acid salt) containing the particle size control agent of the present invention.

[0038] <Example 3>

[0039] 13,409 parts (100 moles) of L(-)-malic acid (Wako Grade I, Fujifilm Wako Pure Chemicals Co., Ltd.) (b13), 16,822 parts (160 moles) of diethanolamine (purity >99.0%, Tokyo Chemical Industry Co., Ltd.) (b23) and 45,348 parts of water were uniformly mixed to obtain an aqueous solution containing the particle size control agent of the present invention (B3; 40% aqueous solution of L(-)-malic acid diethanolamine salt).

[0040] <Example 4>

[0041] 15,009 parts (100 moles) of L(+)-tartaric acid (premium grade, Fujifilm and Koh Genuine Chemicals Co., Ltd.) (b14), 12,216 parts (200 moles) of monoethanolamine (purity >99.0%, Tokyo Chemical Industry Co., Ltd.) (b24) and 40,837 parts of water were uniformly mixed to obtain an aqueous solution containing the particle size control agent of the present invention (B4; 40% aqueous solution of L(+)-tartaric acid monoethanolamine salt).

[0042] <Example 5>

[0043] 19,212 parts (100 moles) of anhydrous citric acid (Wako Premium Grade, Fujifilm Wako Pure Chemicals Co., Ltd.) (b15), 28,449 parts (300 moles) of 2-amino-2-methyl-1-propanol (purity >93.0%, Wako Grade 1, Fujifilm Wako Pure Chemicals Co., Ltd.) (b25) and 67,224 parts of water were uniformly mixed to obtain an aqueous solution containing the particle size control agent of the present invention (B5; 40% aqueous solution of citric acid 2-amino-2-methyl-1-propanol salt).

[0044] <Example 6>

[0045] 3.5 g of an aqueous solution (B1) containing a particle size control agent, 14 g of inorganic microparticles (a1) {AEROXIDE P-90, Evonik Japan Co., Ltd., fumed titanium dioxide, "AEROXIDE" is a registered trademark of Evonik Operations GmbH}, 56 g of water (c) and 210 g of zirconia beads (TORAYCERAM, particle size: 0.1 mm, Toray Industries, Ltd., "TORAYCERAM" is a registered trademark of the company) were added to the grinding chamber (Japanese: ベッセル) (model 2) of a bead mill (Easy Nano RMB II type, AIMEX Co., Ltd.), and the mixture was subjected to rotary processing for 60 minutes using a disc to obtain the inorganic ultrafine particle slurry (1) of the present invention.

[0046] <Example 7>

[0047] Except for changing "aqueous solution containing particle size control agent (B1)" to "aqueous solution containing particle size control agent (B2)", the inorganic ultrafine particle slurry (2) of the present invention was obtained by operating in the same manner as in Example 6.

[0048] <Example 8>

[0049] Except for changing "3.5g of aqueous solution (B1) containing particle size control agent" to "7.0g of aqueous solution (B3) containing particle size control agent", the inorganic ultrafine particle slurry (3) of the present invention was obtained by operating in the same manner as in Example 6.

[0050] <Example 9>

[0051] Except for changing "aqueous solution containing particle size control agent (B1)" to "aqueous solution containing particle size control agent (B4)" and changing "inorganic microparticles (a1)" to "inorganic microparticles (a2) {AEROXIDE P-25, Evonik Japan Co., Ltd., fumed titanium dioxide}", the inorganic ultrafine particle slurry (4) of the present invention was obtained by operating in the same manner as in Example 6.

[0052] <Example 10>

[0053] Except for changing "aqueous solution containing particle size control agent (B1)" to "aqueous solution containing particle size control agent (B5)" and "inorganic microparticles (a1)" to "inorganic microparticles (a2)", the inorganic ultrafine particle slurry (5) of the present invention was obtained by operating in the same manner as in Example 6.

[0054] <Example 11>

[0055] Except for changing "3.5g of aqueous solution (B1) containing particle size control agent" to "5.3g of aqueous solution (B1) containing particle size control agent" and changing "inorganic microparticles (a1)" to "inorganic microparticles (a3) ​​{boehmite CO6, Daimei Chemical Industry Co., Ltd.}", the inorganic ultrafine particle slurry (6) of the present invention was obtained by operating in the same manner as in Example 6.

[0056] <Comparative Example>

[0057] Except for not using "an aqueous solution containing a particle size control agent (B1)", the same procedure as in Example 6 was followed to obtain the inorganic ultrafine particle slurry (H) for comparison.

[0058] Using the inorganic ultrafine particle slurries (1) to (6) obtained in the examples and the inorganic ultrafine particle slurry (H) obtained in the comparative example, the volume average particle size and surface roughness of the slurries were measured as follows, and summarized in the table below.

[0059] 1. Determination of volume average particle size

[0060] Using a nanoparticle analysis apparatus (nanoPartica SZ-100, manufactured by Horiba Manufacturing Co., Ltd.), the particle size representing the 50% cumulative value of the cumulative distribution curve, i.e., the median particle size (D50, dynamic light scattering method), is taken as the volume average particle size (D50).

[0061] It should be noted that the inorganic ultrafine particle slurry (H) obtained in the comparative example has a wide particle size distribution, which is beyond the measurement range of the nanoparticle analysis device. Furthermore, the coarse particles settle quickly, making it impossible to measure the volume average particle size (D50, dynamic scattering method). Therefore, as a comparison, the volume average particle size (D50, laser diffraction method) was measured using a particle size distribution measuring device (Partica LA-960V2, Horiba Manufacturing Co., Ltd., JIS Z 8825:2022 Particle size analysis - Laser diffraction method (corresponding international standard: ISO 13320:2020)). (Note that this method does not have a measurement accuracy below 100 nm in its measurement principle.)

[0062] 2. Surface roughness measurement

[0063] The test sample (inorganic ultrafine particle slurry) was coated (wet thickness of 10 μm) onto a polyethylene terephthalate film and then dried at 70 °C for 30 minutes to form a coated film. Next, the arithmetic mean roughness (Ra) of the coated film was measured using a nano-roughness measuring instrument (Nano Seven TN-A1, Tsukumo Engineering Co., Ltd., JIS B0633:2001 "Geometrical Product Specifications (GPS) - Surface texture: Profile method - Rules and procedures for the assesment of surface texture" (corresponding international standard: ISO 4288:1996, Geometrical Product Specifications (GPS) - Surface texture: Profile method - Rules and procedures for the assesment of surface texture)). (JIS B 0601:2013 "Geometrical Product Specifications (GPS) - Surface texture: Profile method - Terms, definitions and surface texture parameters" (corresponding international standard: ISO 4281:1997, Amd. (2009), Geometrical Product Specifications (GPS) - Surface texture: Profile method - Terms, definitions and surface texture parameters)).

[0064] [Table 1]

[0065]

[0066] As described above, by using the particle size control agent for inorganic ultrafine particle slurries of the present invention, the volume average particle size (D50, dynamic light scattering method) of the inorganic ultrafine particles in the inorganic ultrafine particle slurry can be easily controlled to below 100 nm, and inorganic ultrafine particle slurries with a volume average particle size (D50, dynamic light scattering method) of 100 nm or less in the inorganic ultrafine particle slurry can be easily prepared. Furthermore, compared with the comparative slurry, the inorganic ultrafine particle slurry of the present invention has good surface roughness, and its performance can be easily improved.

Claims

1. A particle size control agent for inorganic ultrafine particle slurry, characterized in that, It is composed of a salt (B) of a hydroxycarboxylic acid with 2 to 7 carbon atoms and an ammonia or an organic amine with 1 to 14 carbon atoms.

2. The particle size control agent for inorganic ultrafine particle slurry according to claim 1, wherein, Salt (B) consists of 100 moles of hydroxycarboxylic acid and 50 to 350 moles of ammonia or organic amine.

3. The particle size control agent for inorganic ultrafine particle slurry according to claim 1, wherein, Inorganic ultrafine particles are metal oxides.

4. An inorganic ultrafine particle slurry, characterized in that, It contains the particle size control agent for inorganic ultrafine particle slurry as described in claim 1, inorganic ultrafine particles (A), and water (C). The volume average particle size D50 of the inorganic ultrafine particles (A) in the slurry obtained by dynamic light scattering method is less than 100 nm.

5. The inorganic ultrafine particle slurry according to claim 4, wherein, The particle size control agent is 5 to 50 parts by weight relative to 100 parts by weight of inorganic ultrafine particles (A).

6. The inorganic ultrafine particle slurry according to claim 4, wherein, Inorganic ultrafine particles (A) are metal oxides.

7. A manufacturing method, characterized in that, This is a method for manufacturing the inorganic ultrafine particle slurry as described in claim 4. It is prepared by rotating beads and discs with diameters of 0.01 mm to 1 mm.

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