Patent CA614669A successfully refreshed from Google Patents.
US5389352A
Expired / Lapsed
US
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Oxide particles and method for producing them
Assignee: DuPont Electronic Materials Holding Inc
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Filing: 1993-07-21
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Granted: 1995-02-14
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Expires: 2013-07-21
Abstract
Abstract The invention is a process for preparing chemically active solid oxide particles useful for polishing, composed primarily of CeO 2 , or CeO 2 together with other oxides, comprising: (a) forming an aqueous solution comprised of a water soluble trivalent cerium salt and an oxidizing agent and (b) aging said mixture in the liquid state for a time not less than 4 hours.
Inventors
- 👤 Jiun-Fang Wang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:58
CPC Classifications
B; B82; B82Y; B82Y30/00; C; C01; C01F; C01F17/00; C01F17/20; C01F17/206; C01F17/224; C01F17/235; C09; C09K; C09K3/00; C09K3/14; C09K3/1409; C01P; C01P2002/00; C01P2002/60; C01P2004/00; C01P2004/60; C01P2004/62; C01P2004/64; C01P2006/00; C01P2006/60
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
66 words
A process for preparing chemically active solid CeO 2 particles useful for polishing comprising: (a) forming an aqueous solution comprised of a water soluble trivalent cerium salt and an oxidizing agent and (b) aging said solution as a liquid phase for a time not less than 4 hours at which time said trivalent cerium salt has been oxidized to said chemically active solid CeO 2 particles.
Claim 2
Dependent Claim
66 words
A process for preparing chemically active solid CeO 2 particles useful for polishing comprising: (a) forming an aqueous solution comprised of a water soluble trivalent cerium salt and an oxidizing agent and (b) aging said solution as a liquid phase for a time not less than 4 hours at which time said trivalent cerium salt has been oxidized to said chemically active solid CeO 2 particles.
Claim 3
Dependent Claim
29 words
A process as set forth in claim 1 wherein said oxidizing agent consists of water and said aging is carried out at a temperature of 100° C. or greater.
Claim 4
Dependent Claim
16 words
A process as set forth in claim 1 wherein said oxidizing agent consists of hydrogen peroxide.
Claim 5
Dependent Claim
19 words
A process as set forth in claim 1 wherein bases or buffers are added to said solution before aging.
Claim 6
Dependent Claim
21 words
A process as set forth in claim 1 wherein said water soluble trivalent cerium salt is Ce(NO 3 ) 3 .
Claim 7
Dependent Claim
38 words
A process as set forth in claim 1, 2, 3, 4 or 5 wherein a salt or salts other than cerium compounds are added to said solution before aging so that particles prepared are a mixture of oxides.
Claim 8
Dependent Claim
18 words
The submicron particles produced from the process as set forth in claim 1, 2, 3, 4 or 5.
Claim 9
Dependent Claim
43 words
The submicron particles produced from the process as set forth in claim 1, 2, 3, 4 or 5 wherein a salt or salts other than cerium compounds are added to said solution before aging so that particles prepared are a mixture of oxides.
References Cited (Backward Citations)
US3311461A
Cited
US3768989A
Cited
US4529410A
Cited
US4619817A
Cited
US5021192A
Cited
US4859432A
Cited
US5026421A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-02-13 | 1998-08-15 | 1999-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-02-13 | 2002-08-15 | 2003-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-02-13 | 2006-08-15 | 2007-02-14 | $7700.00 | Window Closed / Lapsed |