US3085861A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of siliceous pigment
Assignee: PPG Industries Inc
•
Filing: 1955-04-08
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Granted: 1963-04-16
•
Expires: 1975-04-08
Abstract
No abstract record available.
Inventors
- 👤 Fred S Thornhill
- 👤 Raymond S Chisholm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:48
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/18; C01B33/187; C01B33/193; C08; C08K; C08K3/00; C08K3/34; C08K3/36; C01P; C01P2006/00; C01P2006/12; C01P2006/90
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
93 words
A METHOD OF PREPARING FINELY DIVIDED PRECIPITATED SILICEOUS PIGMENT WHICH COMPRISES INTRODUCING AN ACID WHICH FORMS A WATER SOLUBLE SALT OF AN ALKALI META INTO AN AQUEOUS ALKALI METAL SILICATE SOLUTION AT A RATE SUCH THAT THE STOICHIOMETRIC AMOUNT OF ACID REQUIRED TO REACT WITH THE ALKALI METAL SILICATE IS ADDED AND REACTED WITH THE ALKALI METAL SILICATE TO PRECIPITATE PERMANENTLY THE SIO2 CONTENT OF THE ALKALI METAL SILICATE AS SILICEOUS PIGMENT WITHIN A PERIOD LESS THAN 2 MINUTES, WHILE MAINTAINING THE SOLUTION AT A SUPERATMOSPHERIC PRESSURE AND AT A TEMPERATURE ABOVE 100*C.
Claim 2
Independent Claim
93 words
A METHOD OF PREPARING FINELY DIVIDED PRECIPITATED SILICEOUS PIGMENT WHICH COMPRISES INTRODUCING AN ACID WHICH FORMS A WATER SOLUBLE SALT OF AN ALKALI META INTO AN AQUEOUS ALKALI METAL SILICATE SOLUTION AT A RATE SUCH THAT THE STOICHIOMETRIC AMOUNT OF ACID REQUIRED TO REACT WITH THE ALKALI METAL SILICATE IS ADDED AND REACTED WITH THE ALKALI METAL SILICATE TO PRECIPITATE PERMANENTLY THE SIO2 CONTENT OF THE ALKALI METAL SILICATE AS SILICEOUS PIGMENT WITHIN A PERIOD LESS THAN 2 MINUTES, WHILE MAINTAINING THE SOLUTION AT A SUPERATMOSPHERIC PRESSURE AND AT A TEMPERATURE ABOVE 100*C.
References Cited (Backward Citations)
US2496736A
Cited
GB561750A
Cited
US2663650A
Cited
US2679463A
Cited
US2737446A
Cited
US2759798A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-04-15 | 1966-10-15 | 1967-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-04-15 | 1970-10-15 | 1971-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-04-15 | 1974-10-15 | 1975-04-16 | $7700.00 | Window Closed / Lapsed |