US4636374A
Expired / Lapsed
US
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Method for manufacturing aluminum oxynitride refractory
Assignee: Nikkei Kako KK
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Filing: 1985-10-25
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Granted: 1987-01-13
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Expires: 2005-10-25
Abstract
Abstract An aluminum oxynitride refractory of a sufficiently high nitrogen content is produced efficiently and inexpensively by a method which comprises mixing alumina of Bayer Process with aluminum dross and electrically fusing the resultant mixture in an electric furnace.
Inventors
- 👤 Susumu Kurihara
- 👤 Tadashi Seki
- 👤 Hiroshi Awata
- 👤 Hitoshi Kadowaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:05
CPC Classifications
C; C01; C01B; C01B21/00; C01B21/082; C01B21/0821; C01B21/0825; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/581
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
27 words
A method for the manufacture of an aluminum oxynitride refractory, characterized by mixing alumina with aluminum dross and electrically fusing the resultant mixture in an electric furnace.
Claim 2
Independent Claim
27 words
A method for the manufacture of an aluminum oxynitride refractory, characterized by mixing alumina with aluminum dross and electrically fusing the resultant mixture in an electric furnace.
Claim 3
Dependent Claim
40 words
The method of claim 1 wherein said dross contains metallic aluminum and said dross is heated in a nitrogen atmosphere before being mixed with said alumina in order to convert at least some of said aluminum metal to aluminum nitride.
Claim 4
Dependent Claim
41 words
The method of claim 2 wherein additional metallic aluminum is incorporated into said dross before the latter is heated in said nitrogen atmosphere to increase the amount of aluminum nitride in said dross before mixture of the same with said alumina.
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) | 1990-01-12 | 1990-07-14 | 1991-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-12 | 1994-07-14 | 1995-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-12 | 1998-07-14 | 1999-01-13 | $7700.00 | Window Closed / Lapsed |