US2973282A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the surface treatment of finely-divided oxides or oxide mixtures
Assignee: Evonik Operations GmbH
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Filing: 1956-07-20
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Granted: 1961-02-28
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Expires: 1976-07-20
Abstract
No abstract record available.
Inventors
- 👤 Gross Albert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:57
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/28; C09C1/30; C09C1/309; C09C3/00; C09C3/06; C09C3/08; C01; C01P; C01P2006/00; C01P2006/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
A PROCESS FOR IMPROVING THE SURFACE CHARACTERISTICS OF FINELY DIVIDED PYROGENIC SILICA WHICH COMPRISES CONTACTING SUCH SILICA IN THE FORM OF A DRY POWDER WITH A SUBSTANTIALLY ANHYDROUS GAS CONSISTING OF A MINOR PROPORTION OF A STRONG ACID VAPOR AND VAPORS OF ALCOHOLS CONTAINING NOT OVER 20 CARBON ATOMS IN A STRAIGHT OR BRANCHED CHAIN, THE THE MAJORITY OF HYDROXYL GROUPS ON THE SURFACE OF SAID SILICA.
Claim 2
Dependent Claim
67 words
A PROCESS FOR IMPROVING THE SURFACE CHARACTERISTICS OF FINELY DIVIDED PYROGENIC SILICA WHICH COMPRISES CONTACTING SUCH SILICA IN THE FORM OF A DRY POWDER WITH A SUBSTANTIALLY ANHYDROUS GAS CONSISTING OF A MINOR PROPORTION OF A STRONG ACID VAPOR AND VAPORS OF ALCOHOLS CONTAINING NOT OVER 20 CARBON ATOMS IN A STRAIGHT OR BRANCHED CHAIN, THE THE MAJORITY OF HYDROXYL GROUPS ON THE SURFACE OF SAID SILICA.
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) | 1964-02-28 | 1964-08-29 | 1965-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-02-28 | 1968-08-29 | 1969-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-02-28 | 1972-08-29 | 1973-02-28 | $7700.00 | Window Closed / Lapsed |