Patent US3556725A successfully refreshed from Google Patents.
US3556725A
Expired / Lapsed
US
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Process for producing low-bulk density silica
Assignee: GTE Sylvania Inc
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Filing: 1969-02-26
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Granted: 1971-01-19
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Expires: 1989-02-26
Abstract
Abstract AN IMPROVEMENT TO THE PROCESS FOR PRODUCING SILICA FROM TETRAALKYL SILICATE COMPRISING CONDUCTING THE HYDROLYSIS OF THE TETRAALKYL SILICATE IN THE PRESENCE OF A CATIONIC SURFACE ACTIVE AGENT TO THEREBY CONTROL THE BULK DENSITY OF THE RESULTING SILICA BETWEEN BULK DENSITIES OF FROM ABOUT 6 POUNDS PER CUBIC FOOT AND ABOUT 23 POUNDS PER CUBIC FOOT.
Inventors
- 👤 Vincent Chiola
- 👤 Joseph E Ritsko
- 👤 Clarence D Vanderpool
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:41
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/16; C01B33/163; C09; C09K; C09K11/00; C09K11/08; C09K11/59; C09K11/592
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |