US2920974A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing a finely-divided alumina-silica pigment
Assignee: Columbia Southern Chemical Corp
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Filing: 1957-02-15
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Granted: 1960-01-12
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Expires: 1977-02-15
Abstract
No abstract record available.
Inventors
- 👤 Edward M Allen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:09
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/20; C01B33/26; B; B82; B82Y; B82Y30/00; C01B33/36; C01B33/38; C01B33/40; C01B33/42; C01B33/46; C08; C08K; C08K3/00; C08K3/34; C09; C09C; C09C1/00; C09C1/40; C09C1/42; C01P; C01P2002/00; C01P2002/02; C01P2004/00; C01P2004/60; C01P2004/62; C01P2004/64; C01P2004/80; C01P2004/82; C01P2006/00; C01P2006/12; C01P2006/60
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
111 words
A METHOD WHICH COMPRISES PARTIALLY REACTING IN AQUEOUS MEDIUM 25 TO 75 PERCENT OF FINELY DIVIDED ALKALINE EARTH METAL SILICATE WITH A WATER SOLUBLE ACID THE ANION OF WHICH FORMS A WATER SOLUBLE ALKALINE EARTH METAL SALT WHEREBY TO FORM AN ALKALINE EARTH METAL SILICATE-SILICA COMPOSITION, REACTING SAID COMPOSITION IN AQUEOUS MEDIUM WITH A WATER SOLUBLE ALUMINUM SALT, THE ANION OF WHICH FORMS A WATER SOLUBLE ALKALINE EARTH METAL SALT, THE AMOUNT OF SAID ALUMINUM SALT BEING SUFFICIENT TO REPLACE SUBSTANTIALLY ALL OF THE ALKALINE EARTH METAL OXIDE OF THE SAID COMPOSITION WITH AL2O3 WHEREBY TO PRODUCE AN ALUMINA-SILICA COMPOSITION HAVING AN AVERAGE ULTIMATE PARTICLE SIZE OF LESS THAN 1 MICRON.
Claim 2
Independent Claim
111 words
A METHOD WHICH COMPRISES PARTIALLY REACTING IN AQUEOUS MEDIUM 25 TO 75 PERCENT OF FINELY DIVIDED ALKALINE EARTH METAL SILICATE WITH A WATER SOLUBLE ACID THE ANION OF WHICH FORMS A WATER SOLUBLE ALKALINE EARTH METAL SALT WHEREBY TO FORM AN ALKALINE EARTH METAL SILICATE-SILICA COMPOSITION, REACTING SAID COMPOSITION IN AQUEOUS MEDIUM WITH A WATER SOLUBLE ALUMINUM SALT, THE ANION OF WHICH FORMS A WATER SOLUBLE ALKALINE EARTH METAL SALT, THE AMOUNT OF SAID ALUMINUM SALT BEING SUFFICIENT TO REPLACE SUBSTANTIALLY ALL OF THE ALKALINE EARTH METAL OXIDE OF THE SAID COMPOSITION WITH AL2O3 WHEREBY TO PRODUCE AN ALUMINA-SILICA COMPOSITION HAVING AN AVERAGE ULTIMATE PARTICLE SIZE OF LESS THAN 1 MICRON.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-01-11 | 1963-07-13 | 1964-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-11 | 1967-07-13 | 1968-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-11 | 1971-07-13 | 1972-01-12 | $7700.00 | Window Closed / Lapsed |