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US2805955A Expired / Lapsed US ⏱️ 0.0 years remaining

Silica composition and production thereof

Assignee: Columbia Southern Chemical Corp
•
Filing: 1952-04-22
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Granted: 1957-09-10
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Expires: 1972-04-22
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Abstract

No abstract record available.

Inventors

  • 👤 Edward M Allen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 15:42
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.

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

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