US5338353A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for production of powder of fine inorganic particles
Assignee: Nippon Shokubai Co Ltd
•
Filing: 1992-10-20
•
Granted: 1994-08-16
•
Expires: 2012-10-20
Abstract
Abstract A method for the production of powder of fine inorganic particles excellent in dispersibility in various solvents from a slurry of said fine inorganic particles containing water, which method comprises preparing a slurry as a raw material by incorporating in said slurry at least one orgaic compound selected from the group consisting of (A) methanol and (B) organic compound capable of dissolving of dissolving water in an amount of not less than 1.0% by weight at 20 DEG C. and forming a two-component azeotropic mixture of water and organic compounds having a water content of not less than 4.0% by weight and converting said prepared slurry into powder by the use of a powderization apparatus comprising an externally heatable pipe one end of which serves as a slurry inlet and the other end of which serves as a device for separating the produced powder and a vapor held in a vacuum state and a powder and a powder collecting chamber connected to said separating device.
Inventors
- 👤 Hiroyoshi Uchino
- 👤 Tadahiro Yoneda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:45
CPC Classifications
B; B01; B01D; B01D1/00; B01D1/16; B01D1/18; B22; B22F; B22F1/00; B22F1/10; C; C01; C01B; C01B13/00; C01B13/14; C01B13/145; C01B32/00; C01B32/90; C01B32/914; C01B32/956; C01B33/00; C01B33/113; C01B33/12; C01B33/20; C01B33/26; C01F; C01F7/00; C01F7/02; C01G; C01G23/00; C01G23/04; C01G23/047; C01G23/053; C01G25/00; C01G25/02; C01P; C01P2004/00; C01P2004/30; C01P2004/32; C01P2004/51; C01P2004/52; C01P2004/60; C01P2004/61; C01P2004/62; C01P2006/00; C01P2006/10; C01P2006/12; C01P2006/22; C01P2006/80; C01P2006/82
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
282 words
A method for the production of powder of fine metal oxide particles excellent in dispersibility in various solvents comprising hydrolyzing and condensing a hydrolyzable and condensable organic metal compound in an organic solvent in the presence of water to form an aqueous slurry X of fine particles of a metal oxide, preparing a slurry Y comprising said fine particles of a metal oxide and aqueous solvent from said hydrolyzed slurry X; an organic compound (D) capable of reacting with the surfaces of said fine particles and possessing at least one hydroxyl group in the molecular unit, the amount of said organic compound being not less than 0.01 part by weight based on 1 part by weight of said fine particles; and at least one organic constituent selected from the group consisting of (A) methanol, said methanol being present in an amount not less than 1.0 part by weight based on 1 part by weight of the water present in said aqueous solvent and (B) an organic compound capable of forming a binary azeotropic mixture with water, said azeotropic mixture having a concentration of water (Cw) not less than 4.0% by weight, and solubility of water (Sw) to said compound being an amount of not less than 1.0% by weight at 20° C., the amount of said organic compound being not less than 60% of the amount calculated to form a binary azeotropic mixture with water present in said aqueous solvent, and converting said prepared slurry into powder having an average diameter of 0.1 to 30 μm, a coefficient of particle diameter variation in the range of 2 to 30% and having said compound (D) bound to the surface of said fine particles.
Claim 2
Independent Claim
282 words
A method for the production of powder of fine metal oxide particles excellent in dispersibility in various solvents comprising hydrolyzing and condensing a hydrolyzable and condensable organic metal compound in an organic solvent in the presence of water to form an aqueous slurry X of fine particles of a metal oxide, preparing a slurry Y comprising said fine particles of a metal oxide and aqueous solvent from said hydrolyzed slurry X; an organic compound (D) capable of reacting with the surfaces of said fine particles and possessing at least one hydroxyl group in the molecular unit, the amount of said organic compound being not less than 0.01 part by weight based on 1 part by weight of said fine particles; and at least one organic constituent selected from the group consisting of (A) methanol, said methanol being present in an amount not less than 1.0 part by weight based on 1 part by weight of the water present in said aqueous solvent and (B) an organic compound capable of forming a binary azeotropic mixture with water, said azeotropic mixture having a concentration of water (Cw) not less than 4.0% by weight, and solubility of water (Sw) to said compound being an amount of not less than 1.0% by weight at 20° C., the amount of said organic compound being not less than 60% of the amount calculated to form a binary azeotropic mixture with water present in said aqueous solvent, and converting said prepared slurry into powder having an average diameter of 0.1 to 30 μm, a coefficient of particle diameter variation in the range of 2 to 30% and having said compound (D) bound to the surface of said fine particles.
Claim 3
Dependent Claim
24 words
A method according to claim 1, wherein said organic compound (B) possesses a boiling point of not more than 120° C. under normal pressure.
Claim 4
Dependent Claim
24 words
A method according to claim 1, wherein said organic compound (B) possesses a boiling point of not more than 100° C. under normal pressure.
Claim 5
Dependent Claim
36 words
A method according to claim 1, wherein said slurry obtained by hydrolysis and condensation is thermally concentrated to produce a slurry containing said fine particles in concentration in the range of 10 to 40% by weight.
Claim 6
Dependent Claim
17 words
A method according to claim 1, wherein said fine particles in said powder possess a spherical shape.
Claim 7
Dependent Claim
15 words
A method according to claim 1, wherein said organic metal compound is an alkoxy compound.
Claim 8
Dependent Claim
107 words
A method according to claim 6, wherein said alkoxy compound is represented by the general formula I: R.sup.1.sub.m M(OR.sup.2).sub.n (I) wherein M is metal element, R 1 is at least one group selected from the class consisting of hydrogen atom, substituted or unsubstituted alkyl groups up to 10 carbon atoms, aryl group, and unsaturated aliphatic residues, R 2 is an alkyl group, m is 0 or a positive integer, n is an integer of not less than 1, m+n satisfies the valency of said metallic element M, m R 1 may be different from one another, and n R 2 may be similarly different from one another.
Claim 9
Dependent Claim
26 words
A method according to claim 7, wherein said metal element is at least one member selected from the group consisting of silicon, titanium, zirconium, and aluminum.
Claim 10
Dependent Claim
33 words
A method according to claim 1, wherein said fine metal oxide particles have as a main component thereof at least one member selected from the group consisting of silicon, titanium, zirconium, and aluminum.
Claim 11
Dependent Claim
26 words
A method according to claim 1, wherein the water content in said slurry as raw material is in the range of 3 to 30% by weight.
Claim 12
Dependent Claim
143 words
A method for the production of a powder of fine porous metal oxide particles possessing a spherical shape, an average particle diameter in the range of 0.1 to 30 μm, and a coefficient of particle diameter variation in the range of 2 to 30%, satisfying the relation represented by the general formula (II): S×d×p>30 (II) wherein S is the specific surface area (m 2 /g) of said powder of fine particles determined by the BET method, d is the number average particle diameter (m) determined by observation under an electron microscope, and p is the density (g/m 2 ) of said powder of fine particles, and conferring satisfactory dispersibility upon said powder, which method comprises preparing a powder by the method of claim 1 further comprising calcining said powder at a temperature exceeding the temperature at which said bound organic compound is decomposed.
Claim 13
Dependent Claim
16 words
A method according to claim 11, wherein said organic compound possesses at least two carbon atoms.
Claim 14
Dependent Claim
19 words
A method according to claim 11, wherein the calcination temperature is in the range of 300° to 800° C.
Claim 15
Dependent Claim
37 words
A method according to claim 1, wherein said slurry obtained by hydrolysis and condensation is thermally concentrated to produce a slurry containing said fine particles in a concentration in the range of 10 to 40% by weight.
Claim 16
Dependent Claim
43 words
A method according to claim 1, wherein said fine particles in said powder possess a spherical shape, an average particle diameter in the range of 0.1 to 30 μm, and a coefficient of particle diameter variation in the range of 2 to 30%.
Claim 17
Dependent Claim
15 words
A method according to claim 1, wherein said organic metal compound is an alkoxy compound.
Claim 18
Dependent Claim
107 words
A method according to claim 16, wherein said alkoxy compound is represented by the general formula I: R.sup.1.sub.m M(OR.sup.2).sub.n (I) wherein M is metal element, R 1 is at least one group selected from the class consisting of hydrogen atom, substituted or unsubstituted alkyl groups up to 10 carbon atoms, aryl group, and unsaturated aliphatic residues, R 2 is an alkyl group, m is 0 or a positive integer, n is an integer of not less than 1, m+n satisfies the valency of said metallic element M, m R 1 may be different from one another, and n R 2 may be similarly different from one another.
Claim 19
Dependent Claim
26 words
A method according to claim 17, wherein said metal element is at least one member selected from the group consisting of silicon, titanium, zirconium and aluminum.
Claim 20
Dependent Claim
33 words
A method according to claim 11, wherein said fine metal oxide particles have as a main component thereof at least one member selected from the group consisting of silicon, titanium, zirconium, and aluminum.
Claim 21
Dependent Claim
26 words
A method according to claim 11, wherein the water content in said slurry as raw material is in the range of 3 to 30% by weight.
Claim 22
Dependent Claim
44 words
A method according to claim 1, wherein said organic solvent contains at least one member selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, isobutanol, tert-butanol, methylethyl ketone, tetrahydrofuran, dioxane, ethylene glycol, propylene glycol, 2-methoxy ethanol, 2-ethoxy ethanol and 2-butoxy ethanol.
Claim 23
Dependent Claim
85 words
The method for the production of powder of fine metal oxide particulates excellent in dispersitity as described in claim 1, wherein said prepared slurry is converted into said powder by the use of a powderization apparatus comprising (1) an externally heatable pipe, one end of which serves as a slurry inlet and the other end of which serves as a device for separating the produced powder and a vapor held in a vacuum state, and (2) a powder collecting chamber connected to said separating device.
References Cited (Backward Citations)
JPS5238272A
Cited
JPS5538588A
Cited
JPS5835736A
Cited
US4923520A
Cited
US4615912A
Cited
US4566908A
Cited
GB2166126A
Cited
GB2168334A
Cited
US4649037A
Cited
US4713233A
Cited
EP0199930A2
Cited
JPS62138310A
Cited
US4894092A
Cited
JPS63185439A
Cited
US4810578A
Cited
JPS6444098A
Cited
WO1989003365A1
Cited
US4845056A
Cited
US4839944A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-08-15 | 1998-02-14 | 1998-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-15 | 2002-02-14 | 2002-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-15 | 2006-02-14 | 2006-08-16 | $7700.00 | Window Closed / Lapsed |