Patent US2805955A successfully refreshed from Google Patents.
US2805955A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silica composition and production thereof
Assignee: Columbia Southern Chemical Corp
•
Filing: 1952-04-22
•
Granted: 1957-09-10
•
Expires: 1972-04-22
Abstract
No abstract record available.
Inventors
- 👤 Edward M Allen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:56
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/18; B; B82; B82Y; B82Y30/00; C01B33/187; C01B33/193; C08; C08K; C08K3/00; C08K3/34; C08K3/36; C09; C09C; C09C1/00; C09C1/28; C09C1/30; C09C1/3045; C01P; C01P2002/00; C01P2002/50; C01P2002/52; C01P2004/00; C01P2004/01; C01P2004/03; C01P2004/50; C01P2004/60; C01P2004/64; C01P2006/00; C01P2006/10; C01P2006/12; C01P2006/80; C01P2006/82; C01P2006/90
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
154 words
A METHOD OF PREPARING A FINELY DIVIDED SILICA PIGMENT WHICH COMPRISES MERGING FLOWING STREAMS OF AN AQUEOUS SOLUTION OF SODIUM SILICATE CONTAINING 100 GRAMS PER LITER OF SIO2 AS NA2O(SIO2)3.36 AND A CALCIUM CHLORIDE SOLUTION CONTAINING 100 GRAMS PER LITER OF CACI2 AND FROM ABOUT 0.2 TO 0.5 POUND OF SODIUM CHLORIDE PER POUND OF CACI2, VIGOROUSLY AGITATING THE STREAMS AT THE POINT OF MERGENCE WHEREBY TO ACHIEVE INSTANTANEOUS MIXING OF THE STREAMS AND TO PRODUCE A FLOWING STREAM OF A SLURRY OF CALCIUM SILICATE WHILE ADJUSTING THE FLOW OF SAID STREAMS SO THAT CALCIUM CHLORIDE IS APPROXIMATELY 10 PERCENT IN EXCESS OVER THE STOICHIOMETRIC QUANTITY REQUIRED FOR REACTION, REACTING THE RESULTING CALCIUM SILICATE WITH HYDROCHLORIC ACID TO REDUCE THE PH OF THE SLURRY TO ABOUT 2 AND THEREAFTER ADDING SUFFICIENT SODIUM HYDROXIDE TO THE RESULTING MIXTURE TO RAISE THE PH OF THE SLURRY TO ABOUT 7.5, AND RECOVERING AND DRYING THE RESULTING SILICA.
Claim 2
Independent Claim
154 words
A METHOD OF PREPARING A FINELY DIVIDED SILICA PIGMENT WHICH COMPRISES MERGING FLOWING STREAMS OF AN AQUEOUS SOLUTION OF SODIUM SILICATE CONTAINING 100 GRAMS PER LITER OF SIO2 AS NA2O(SIO2)3.36 AND A CALCIUM CHLORIDE SOLUTION CONTAINING 100 GRAMS PER LITER OF CACI2 AND FROM ABOUT 0.2 TO 0.5 POUND OF SODIUM CHLORIDE PER POUND OF CACI2, VIGOROUSLY AGITATING THE STREAMS AT THE POINT OF MERGENCE WHEREBY TO ACHIEVE INSTANTANEOUS MIXING OF THE STREAMS AND TO PRODUCE A FLOWING STREAM OF A SLURRY OF CALCIUM SILICATE WHILE ADJUSTING THE FLOW OF SAID STREAMS SO THAT CALCIUM CHLORIDE IS APPROXIMATELY 10 PERCENT IN EXCESS OVER THE STOICHIOMETRIC QUANTITY REQUIRED FOR REACTION, REACTING THE RESULTING CALCIUM SILICATE WITH HYDROCHLORIC ACID TO REDUCE THE PH OF THE SLURRY TO ABOUT 2 AND THEREAFTER ADDING SUFFICIENT SODIUM HYDROXIDE TO THE RESULTING MIXTURE TO RAISE THE PH OF THE SLURRY TO ABOUT 7.5, AND RECOVERING AND DRYING THE RESULTING SILICA.
Claim 3
Dependent Claim
123 words
FINELY DIVIDED, PRECIPITATED SILICA PIGMENT CAPAB OF PRODUCING GR-S RUBBER HAVING A TENSILE STRENGTH OF AT LEAST 2440 POUNDS PER SQUARE INCH WHEN MILLED WITH GR-S RUBBER AND THE RESULTING MIXTURE VULCANIZED, SAID PIGMENT CONTAINING AT LEAST 90 PERCENT BY WEIGHT OF SIO2 MEASURED ON THE ANHYDROUS BASIS, BOUND WATER IN THE PROPORTION OF ONE MOLE OF WATER PER 3 TO 9 MOLES OF SIO2, THE FREE WATER CONTENT OF SAID PIGMENT BEING 2 TO 10 PERCENT BY WEIGHT; SAID PIGMENT BEING IN THE FORM OF POROUS FLOCS AND HAVING A SURFACE AREA OF 75 TO 200 SQUARE METERS PER GRAM AND AN AVERAGE ULTIMATE PARTICLE SIZE OF 0.015 TO 0.05 MICRON AND BEING SUBSTANTIALLY IDENTICAL TO THAT PREPARED ACCORDING TO CLAIM 1.
References Cited (Backward Citations)
US1715439A
Cited
GB299483A
Cited
US2114123A
Cited
US2237374A
Cited
US2204113A
Cited
US2259482A
Cited
US2287700A
Cited
US2314188A
Cited
US2496736A
Cited
GB561750A
Cited
US2462236A
Cited
US2438560A
Cited
US2560043A
Cited
US2588853A
Cited
US2649388A
Cited
US2601235A
Cited
US2679463A
Cited
US2605228A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-09-09 | 1961-03-11 | 1961-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-09 | 1965-03-11 | 1965-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-09 | 1969-03-11 | 1969-09-10 | $7700.00 | Window Closed / Lapsed |