US3090678A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of refining silicon
Assignee: American Metal Products Co
•
Filing: 1960-02-24
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Granted: 1963-05-21
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Expires: 1980-02-24
Abstract
No abstract record available.
Inventors
- 👤 John G Lewis
- 👤 Harold A Ohlgren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:59
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/02; C01B33/037
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
91 words
A PROCESS FOR PURIFYING IMPURE SILICON METAL COMPRISING PLACING IMPURE SILICON TO BE PURIFIED IN A DISTILLATION ZONE, REDUCING THE PRESSURE IN SAID ZONE TO A PRESSURE ABOUT 1 TO 10 MICRONS OF MERCURY ABSOLUTE, SUPPLYING ARGON TO SAID ZONE AND MAINTAINING THE PRESSURE IN SAID ZONE BETWEEN ABOUT 1000 TO 30,000 MICRONS OF MERCURY ABSOLUTE, OUTPASSING SAID ZONE WITH ARGON CONCURRENTLY WITH HEATING SAID ZONE TO A TEMPERATURE OF ABOUT 2000 TO 25000*F., FURTHER HEATING SAID ZONE TO A TEMPERATURE ABOUT 3500 TO 4500*F. SO AS TO VAPORIZE SAID SILI-
References Cited (Backward Citations)
US2901325A
Cited
US2992080A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-05-20 | 1966-11-19 | 1967-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-05-20 | 1970-11-19 | 1971-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-05-20 | 1974-11-19 | 1975-05-21 | $7700.00 | Window Closed / Lapsed |