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US4049463A
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Method for producing a pure cerium oxide
Assignee: Treibacher Chemische Werke AG
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Filing: 1976-07-21
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Granted: 1977-09-20
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Expires: 1996-07-21
Abstract
Abstract The brightness of a cerium oxide is improved by adding a boron compound to a cerium salt or a mixture of cerium salts, and the calcining the mixture in the presence of air in a conventional manner.
Inventors
- 👤 Leo Hafner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:24
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/0009; C01; C01F; C01F17/00; C01F17/20; C01F17/206; C01F17/224; C01F17/235; C09K; C09K3/00; C09K3/14; C09K3/1454; C01P; C01P2002/00; C01P2002/50; C01P2002/52
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
96 words
A method of improving the brightness of a cerium oxide, comprising the steps of adding a boron compound to a cerium salt or a mixture of cerium salts selected from the group consisting of cerium oxalate, cerium carbonate and cerium oxide hydrate, and then calcining the mixture in the presence of air, the boron compound being capable of producing B 2 O 3 on calcining and being added in an amount to provide, calculated as B 2 O 3 , 0.05% to 5%, by weight, of the boron compound, based on the weight of cerium oxide.
Claim 2
Independent Claim
96 words
A method of improving the brightness of a cerium oxide, comprising the steps of adding a boron compound to a cerium salt or a mixture of cerium salts selected from the group consisting of cerium oxalate, cerium carbonate and cerium oxide hydrate, and then calcining the mixture in the presence of air, the boron compound being capable of producing B 2 O 3 on calcining and being added in an amount to provide, calculated as B 2 O 3 , 0.05% to 5%, by weight, of the boron compound, based on the weight of cerium oxide.
Claim 3
Dependent Claim
24 words
The method of claim 1, wherein the boron compound is selected from ammonium pentaborate and Na 2 B 4 O 7 .10H 2 O.
Claim 4
Dependent Claim
17 words
The method of claim 1, wherein the boron compound is added in the form of a solution.
Claim 5
Dependent Claim
12 words
The method of claim 1, wherein the boron compound is boric acid.
Claim 6
Dependent Claim
14 words
The method of claim 1, wherein the amount is 0.5 to 1.5%, by weight.
Claim 7
Dependent Claim
16 words
The method of claim 1, wherein the calcining temperature is between 600° C. and 1200° C.
Claim 8
Dependent Claim
16 words
The method of claim 6, wherein the calcining temperature is between 750° C. and 1050° C.
Claim 9
Dependent Claim
16 words
The method of claim 7, wherein the calcining temperature is between 850° C. and 950° C.
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) | 1980-09-19 | 1981-03-21 | 1981-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-19 | 1985-03-21 | 1985-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-19 | 1989-03-21 | 1989-09-20 | $7700.00 | Window Closed / Lapsed |