US2879546A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silica extrusions
Assignee: WR Grace and Co
•
Filing: 1955-08-29
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Granted: 1959-03-31
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Expires: 1975-08-29
Abstract
No abstract record available.
Inventors
- 👤 Adley W Hemphill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:51
CPC Classifications
B; B01; B01J; B01J21/00; B01J21/06; B01J21/08; C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/14; C01B33/157; Y; Y10; Y10S; Y10S425/00; Y10S425/101
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
101 words
A METHOD FOR PREPARING CONSISTENT SILICA EXTRUSIONS WITHOUT THE USE OF EXTERNAL AGENTS HAVING ANY BINDING AND PLASTICIZING EFFECTS WHICH COMPRISES PASSING A MASS OF ALKALINE SILICA HYDROGEL INTO A HEATED EXTRUDER MAINTAINED UNDER NON-EVAPORATIVE CONDITIONS AND AT A TEMPERATURE OF ABOUT 175* F. TO 390* F. FOR A PERIOD OF TIME SUFFICIENT ONLY TO INDUCE PARTIAL REVERSION OF THE HYDROGEL TO A HYDROSOL, AND FORCING SAID MASS THROUGH SAID EXTRUDER TO FORM A SHAPED PARTICLES THEREOF, AND RESETTING TO THE HYDROGEL THE HYDROSOL WHICH IS FORMED DURING THE PARTIAL REVERSION STEP AND THEREBY FORMING NEW STRUCTURAL LINKAGES WITHIN THE EXTRUDATE.
Claim 2
Independent Claim
101 words
A METHOD FOR PREPARING CONSISTENT SILICA EXTRUSIONS WITHOUT THE USE OF EXTERNAL AGENTS HAVING ANY BINDING AND PLASTICIZING EFFECTS WHICH COMPRISES PASSING A MASS OF ALKALINE SILICA HYDROGEL INTO A HEATED EXTRUDER MAINTAINED UNDER NON-EVAPORATIVE CONDITIONS AND AT A TEMPERATURE OF ABOUT 175* F. TO 390* F. FOR A PERIOD OF TIME SUFFICIENT ONLY TO INDUCE PARTIAL REVERSION OF THE HYDROGEL TO A HYDROSOL, AND FORCING SAID MASS THROUGH SAID EXTRUDER TO FORM A SHAPED PARTICLES THEREOF, AND RESETTING TO THE HYDROGEL THE HYDROSOL WHICH IS FORMED DURING THE PARTIAL REVERSION STEP AND THEREBY FORMING NEW STRUCTURAL LINKAGES WITHIN THE EXTRUDATE.
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) | 1962-03-30 | 1962-09-29 | 1963-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-03-30 | 1966-09-29 | 1967-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-03-30 | 1970-09-29 | 1971-03-31 | $7700.00 | Window Closed / Lapsed |