Patent US3339730A successfully refreshed from Google Patents.
Patent US4788080A successfully refreshed from Google Patents.
US4788080A
Expired / Lapsed
US
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Process and apparatus for coating particles with fine powder
Assignee: National Research Council Canada
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Filing: 1987-04-27
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Granted: 1988-11-29
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Expires: 2007-04-27
Abstract
Abstract There is disclosed a process for coating particles, such as ceramic, metallic and organic cores, with fine powder, such as ceramic, metal, organic or carbon powder. The process comprises providing a mixture comprising the particles and a binder which is capable of slowly melting to viscous state. Then the mixture is tumbled while slowly heating it to enable the binder to reach the viscous state while allowing the particles to be substantially covered with the binder. The next step includes cooling the mixture to about room temperature and thereafter breaking up the particles that may have agglomerated during the tumbling and heating to give individual particles covered with the binder. As a final step, the fine powder is added to the individual binder covered particles and the mixture is tumbled and heated again to the viscous state under conditions effective to provide a coating of the fine powder on the particles. Additional heating may be carried out to remove the binder and leave particles exclusively coated with the fine powder. The apparatus includes a rotating cylinder, heating and cooling means. The resulting product has a more uniform microstructure and higher bonding strength than a product resulting from a conventional mixing of ingredients.
Inventors
- 👤 Junichi Hojo
- 👤 Serge Dallaire
- 👤 Blaise Champagne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:05
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; B; B01; B01J; B01J2/00; B01J2/006; B05; B05D; B05D1/00; B05D7/00; B22; B22F; B22F1/00; B22F1/16; B22F1/18; C04B41/45; C04B41/4584; C04B41/80; C04B41/81; B05D2258/00
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
143 words
a process for coating ceramic or metallic particles with fine powder selected from metal powders, ceramic powders, and carbon or plastic powders which comprises: a. providing a mixture comprising said particles and a binder which is capable of slowly melting to viscous state at temperatures up to about 85° C., b. tumbling said mixture while slowly heating same to enable said binder to reach said viscous state while allowing said particles to be substantially covered with said binder, c. cooling the mixture substantially to room temperature and thereafter breaking up agglomerates that have formed during said tumbling and heating, to give individual particles covered with said binder, d. adding said fine powder to said individual particles covered with said binder and tumbling and heating again to said viscous state under conditions effective to provide a coating of said fine powder on said particles.
Claim 2
Dependent Claim
143 words
a process for coating ceramic or metallic particles with fine powder selected from metal powders, ceramic powders, and carbon or plastic powders which comprises: a. providing a mixture comprising said particles and a binder which is capable of slowly melting to viscous state at temperatures up to about 85° C., b. tumbling said mixture while slowly heating same to enable said binder to reach said viscous state while allowing said particles to be substantially covered with said binder, c. cooling the mixture substantially to room temperature and thereafter breaking up agglomerates that have formed during said tumbling and heating, to give individual particles covered with said binder, d. adding said fine powder to said individual particles covered with said binder and tumbling and heating again to said viscous state under conditions effective to provide a coating of said fine powder on said particles.
Claim 3
Dependent Claim
26 words
Process according to claim 1, which further comprises e. heating said coated particles to remove said binder leaving said particles exclusively coated with said fine powder.
Claim 4
Dependent Claim
26 words
Process according to claim 1, wherein said particles consist of ceramic cores selected from the group consisting of particles of oxides, borides, nitrides, silicides and carbides.
Claim 5
Dependent Claim
23 words
Process according to claim 1, wherein said particles consist of metallic cores selected from Fe, Ni, Co, Cr, Cu, Al and alloys thereof.
Claim 6
Dependent Claim
16 words
Process according to claim 1, wherein said cores have a mean diameter of about 40-5000 μm.
Claim 7
Dependent Claim
38 words
Process according to claim 1, wherein said fine powder is selected from the group consisting of fine metal powders selected from one of the element groups IVB, VB, VIB, VIII, IB, IIB, IIIA and IVA and alloys thereof.
Claim 8
Dependent Claim
13 words
Process according to claim 1, wherein said fine powder is a ceramic powder.
Claim 9
Dependent Claim
17 words
Process according to claim 5, wherein said fine metal powders have a mean diameter of 0.1-10 μm.
Claim 10
Dependent Claim
27 words
Process according to claim 1, which comprises adding a surfactant to said fine powder which will inhibit agglomeration thereof when coating said particles with said fine powder.
Claim 11
Dependent Claim
11 words
Process according to claim 9, wherein said surfactant comprises aluminum stearate.
Claim 12
Dependent Claim
19 words
Process according to claim 1, wherein said binder is selected from the group consisting of polyethylene glycol and paraffin.
Claim 13
Dependent Claim
24 words
Process according to claim 1, wherein said tumbling is carried out in a rotating cylindrical container which is tilted with respect to horizontal axis.
Claim 14
Dependent Claim
27 words
Process according to claim 1, which comprises adding about 5 to about 30 volume percent of said fine powder with respect to the volume of said particles.
Claim 15
Dependent Claim
21 words
Process according to claim 1, wherein the mixture of particles and binder comprises about 0.5 to about 5 weight percent binder.
Claim 16
Dependent Claim
23 words
Process according to claim 1, wherein heating in steps b. and c. is carried out up to a temperature of about 80° C.
Claim 17
Dependent Claim
19 words
Process according to claim 11, wherein said cooling is carried out by air blowing while said cylinder is rotating.
Claim 18
Dependent Claim
15 words
Process according to claim 9, which comprises adding less than about 0.5 weight percent surfactant.
Claim 19
Dependent Claim
229 words
A process of coating ceramic particles with fine metallic powder which comprises: a. providing a mixture comprising ceramic cores selected from the group consisting of Al 2 O 3 and SiC particles, and a binder selected from the group consisting of polyethylene glycol and paraffin, said binder being present in an amount of about 0.5 to about 5 weight percent of said ceramic cores, said binder being capable of reaching viscous state below about 80° C., b. tumbling said mixture in a rotating cylindrical container which is tilted with respect to horizontal axis, while heating said mixture to a temperature up to about 80° C. to enable said binder to reach said viscous state, and allowing said particles to be substantially covered with said binder, c. cooling the mixture of binder covered particles substantially to room temperature and thereafter breaking up particles that may have agglomerated during said tumbling and heating by tumbling same with ball means, to give individual particles covered with said binder, d. adding a fine metal powder selected from the group consisting al Al, Cr, Fe, Ni, Co, Mo and W to said individual particles covered with binder and tumbling and heating again in said rotating cylindrical container at a temperature up to about 80° C. to said viscous state under conditions effective to provide a coating of said fine metallic powder on said particles.
Claim 20
Dependent Claim
229 words
A process of coating ceramic particles with fine metallic powder which comprises: a. providing a mixture comprising ceramic cores selected from the group consisting of Al 2 O 3 and SiC particles, and a binder selected from the group consisting of polyethylene glycol and paraffin, said binder being present in an amount of about 0.5 to about 5 weight percent of said ceramic cores, said binder being capable of reaching viscous state below about 80° C., b. tumbling said mixture in a rotating cylindrical container which is tilted with respect to horizontal axis, while heating said mixture to a temperature up to about 80° C. to enable said binder to reach said viscous state, and allowing said particles to be substantially covered with said binder, c. cooling the mixture of binder covered particles substantially to room temperature and thereafter breaking up particles that may have agglomerated during said tumbling and heating by tumbling same with ball means, to give individual particles covered with said binder, d. adding a fine metal powder selected from the group consisting al Al, Cr, Fe, Ni, Co, Mo and W to said individual particles covered with binder and tumbling and heating again in said rotating cylindrical container at a temperature up to about 80° C. to said viscous state under conditions effective to provide a coating of said fine metallic powder on said particles.
Claim 21
Dependent Claim
142 words
A process for coating particles with fine powder which comprises: a. providing a mixture comprising said particles and a binder which is capable of slowly melting to viscous state, b. tumbling said mixture while slowly heating same to enable said binder to reach said viscous state while allowing said particles to be substantially covered with said binder, c. cooling the mixture substantially to room temperature and thereafter breaking up particles that may have agglomerated during said tumbling and heating, to give individual particles covered with said binder, d. adding said fine powder to said individual particles covered with said binder and tumbling and heating again to said viscous state under conditions effective to provide a coating of said fine powder on said particles, and e. heating said coated particles to remove said binder leaving said particles exclusively coated with said fine powder.
Claim 22
Dependent Claim
142 words
A process for coating particles with fine powder which comprises: a. providing a mixture comprising said particles and a binder which is capable of slowly melting to viscous state, b. tumbling said mixture while slowly heating same to enable said binder to reach said viscous state while allowing said particles to be substantially covered with said binder, c. cooling the mixture substantially to room temperature and thereafter breaking up particles that may have agglomerated during said tumbling and heating, to give individual particles covered with said binder, d. adding said fine powder to said individual particles covered with said binder and tumbling and heating again to said viscous state under conditions effective to provide a coating of said fine powder on said particles, and e. heating said coated particles to remove said binder leaving said particles exclusively coated with said fine powder.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-11-29 | 1992-05-30 | 1992-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-29 | 1996-05-30 | 1996-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-29 | 2000-05-30 | 2000-11-29 | $7700.00 | Window Closed / Lapsed |