Patent US3650693A successfully refreshed from Google Patents.
US3650693A
Expired / Lapsed
US
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Preparation of fibrous titanium dioxide
Assignee: EIDP Inc
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Filing: 1970-09-24
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Granted: 1972-03-21
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Expires: 1990-09-24
Abstract
Abstract A process is described for producing rutile fibers of unusual dimensional uniformity. Titanium trichloride is reacted at 960*990* C. with humidified oxygen followed by dry oxygen in the presence of molten sodium and potassium chloride mixtures containing preformed titanium dioxide of pigmentary size.
Inventors
- 👤 Hans J Borchardt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:40
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/62227; C04B35/62231; C01; C01G; C01G23/00; C01G23/04; C01G23/047; C01G23/07; C01P; C01P2004/00; C01P2004/10; C01P2004/60; C01P2004/61
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
110 words
The process of claim 1 wherein: In step (a) said reaction mixture comprises 14-17 percent by weight of titanium trichloride, 77-82 percent by weight of an equimolar mixture of sodium chloride and potassium chloride, and 4-6 percent by weight of pigmentary rutile titanium dioxide, and the reaction temperature is between 960*-990* C., In step (b) the humidified oxygen contains 0.4-0.6 atmospheres partial pressure of water vapor and is added at a rate of 5-6 milliliters per minute per gram of reaction mixture for 5-7 minutes, and In step (c) dry oxygen is added at a flow rate of 2.5-3.0 milliliters per minute per gram of reaction mixture for 13-15 minutes.
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) | 1975-03-21 | 1975-09-20 | 1976-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-21 | 1979-09-20 | 1980-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-21 | 1983-09-20 | 1984-03-21 | $7700.00 | Window Closed / Lapsed |