US4686774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for dehydration of a composition of a fine powder and water
Assignee: Resonac Holdings Corp
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Filing: 1986-08-28
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Granted: 1987-08-18
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Expires: 2006-08-28
Abstract
Abstract From a composition of a fine powder and water, a fine powder minimally susceptible of agglomeration is obtained by a method which comprises adding to the composition of a fine powder and water a water-insoluble organic solvent at least in an amount enough for consequently forming an azeotropic composition with respect to the amount of the water involved, converting the resulting mixed liquid into a W/O type emulsion, and removing the water and the organic solvent from the emulsion.
Inventors
- 👤 Tadashi Hiraiwa
- 👤 Eizi Ando
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:29
CPC Classifications
F; F26; F26B; F26B5/00; F26B5/005
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
77 words
A method for removing water from a composition consisting essentially of water and a fine ceramic powder, which comprises: (a) adding to said composition a water-insoluble organic solvent at least in an amount sufficient to form an azeotrope with the water in said composition, (b) converting the resulting mixed liquid into a W/O emulsion having minute ceramic particles contained in water droplets suspended in said emulsion, and (c) removing the water and organic solvent from said emulsion.
Claim 2
Independent Claim
77 words
A method for removing water from a composition consisting essentially of water and a fine ceramic powder, which comprises: (a) adding to said composition a water-insoluble organic solvent at least in an amount sufficient to form an azeotrope with the water in said composition, (b) converting the resulting mixed liquid into a W/O emulsion having minute ceramic particles contained in water droplets suspended in said emulsion, and (c) removing the water and organic solvent from said emulsion.
Claim 3
Dependent Claim
29 words
The method according to claim 1, wherein the amount of said organic solvent added to said composition is sufficient to form an azeotrope with the water in said composition.
Claim 4
Dependent Claim
24 words
The method according to claim 1, wherein said water-insoluble organic solvent is selected from the group consisting of carbon tetrachloride, toluene, xylene, and benzene.
Claim 5
Dependent Claim
21 words
The method according to claim 1, wherein said removal of water and organic solvent from said emulsion is effected by distillation.
Claim 6
Dependent Claim
18 words
The method according to claim 1, wherein the organic solvent is recovered from the water by quiescent standing.
Claim 7
Dependent Claim
24 words
The method according to claim 1, wherein the removal of water and organic solvent from said emulsion is effected by a vacuum spray method.
Claim 8
Dependent Claim
26 words
The method according to claim 1, wherein said resulting mixed liquid is converted to a W/O emulsion either mechanically or by the addition of a surfactant.
Claim 9
Dependent Claim
17 words
The method according to claim 7, wherein said surfactant is an anionic, a cationic or non-ionic surfactant.
Claim 10
Dependent Claim
20 words
The method according to claim 8, wherein said emulsion formed has a HLB within the range of 3 to 10.
Claim 11
Dependent Claim
25 words
The method according to claim 8, wherein said emulsion formed has water dispered in the form of droplets which are about 1 μm in diameter.
Claim 12
Dependent Claim
12 words
The method according to claim 3, wherein said water-insoluble solvent is toluene.
Claim 13
Independent Claim
95 words
A method for forming fine powder particles consisting essentially of particles whose diameters are not more than about 1 μm, which comprises: (a) adding to a composition consisting essentially of water and a fine powder, a water-insoluble organic solvent at least in an amount sufficient to form an azeotrope with the water in said composition; (b) converting the resulting mixed liquid into a W/O emulsion having minute ceramic particles contained in water droplets suspended in said emulsion; and (c) removing the water and organic solvent from the emulsion, to thereby obtain dry, fine powder particles.
Claim 14
Independent Claim
95 words
A method for forming fine powder particles consisting essentially of particles whose diameters are not more than about 1 μm, which comprises: (a) adding to a composition consisting essentially of water and a fine powder, a water-insoluble organic solvent at least in an amount sufficient to form an azeotrope with the water in said composition; (b) converting the resulting mixed liquid into a W/O emulsion having minute ceramic particles contained in water droplets suspended in said emulsion; and (c) removing the water and organic solvent from the emulsion, to thereby obtain dry, fine powder particles.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-17 | 1991-02-16 | 1991-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-17 | 1995-02-16 | 1995-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-17 | 1999-02-16 | 1999-08-18 | $7700.00 | Window Closed / Lapsed |