US2520850A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of whitening alkaline earth carbonates
Assignee: Individual
•
Filing: 1944-02-12
•
Granted: 1950-08-29
•
Expires: 1964-02-12
Abstract
No abstract record available.
Inventors
- 👤 Minnick Leonard John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:14
CPC Classifications
C; C01; C01F; C01F11/00; C01F11/18; C01F11/186; C01F11/185; C01F11/188; C01F5/00; C01F5/24; C09; C09C; C09C1/00; C09C1/02; C09C1/021; C09C1/022; C09C1/028; C01P; C01P2006/00; C01P2006/60
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
127 words
THE PROCESS OF TREATING A CHEMICALLY PRODUCED SUBSTANTIALLY WATER-INSOLUBLE CARBONATE SELECTED FROM THE GROUP CONSISTING OF CALCIUM, STRONTIUM, BARIUM AND MAGNESIUM CARBONATE DISCOLORED BY FERRIC IRON TO FORM A SUBSTANTIALLY WHITE PRODUCT WHICH COMPRISES MIXING, WITH SAID CARBONATE IN THE PRESENCE OF WATER, A RELATIVELY SMALL AMOUNT OF A NON-COLOR-IMPARTING REDUCING AGENT SELECTED FROM THE GROUP CONSISTING OF REDUCING ACIDS AND REDUCING SALTS AND WHICH WILL CONVERT FERRIC IRON TO FERROUS IRON IN A SUBSTANTIALLY NEUTRAL MEDIUM; AND DIGESTING SAID MIXTURE AT A TEMPERATURE ABOVE ABOUT 140*F. WHEREBY ENOUGH OF SAID FERRIC IRON PRESENT IN THE CARBONATE IS CONVERTED INTO AN ASSOCIATING COMPOUND OF SAID IRON AND REDUCING AGENT AND WHICH ASSOCIATION IMPARTS SUBSTANTIALLY NO COLORATION TO THE PRODUCT SO THAT SAID PRODUCT IS RENDERED SUBSTANTIALLY WHITE.
Claim 2
Dependent Claim
127 words
THE PROCESS OF TREATING A CHEMICALLY PRODUCED SUBSTANTIALLY WATER-INSOLUBLE CARBONATE SELECTED FROM THE GROUP CONSISTING OF CALCIUM, STRONTIUM, BARIUM AND MAGNESIUM CARBONATE DISCOLORED BY FERRIC IRON TO FORM A SUBSTANTIALLY WHITE PRODUCT WHICH COMPRISES MIXING, WITH SAID CARBONATE IN THE PRESENCE OF WATER, A RELATIVELY SMALL AMOUNT OF A NON-COLOR-IMPARTING REDUCING AGENT SELECTED FROM THE GROUP CONSISTING OF REDUCING ACIDS AND REDUCING SALTS AND WHICH WILL CONVERT FERRIC IRON TO FERROUS IRON IN A SUBSTANTIALLY NEUTRAL MEDIUM; AND DIGESTING SAID MIXTURE AT A TEMPERATURE ABOVE ABOUT 140*F. WHEREBY ENOUGH OF SAID FERRIC IRON PRESENT IN THE CARBONATE IS CONVERTED INTO AN ASSOCIATING COMPOUND OF SAID IRON AND REDUCING AGENT AND WHICH ASSOCIATION IMPARTS SUBSTANTIALLY NO COLORATION TO THE PRODUCT SO THAT SAID PRODUCT IS RENDERED SUBSTANTIALLY WHITE.
References Cited (Backward Citations)
US233916A
Cited
GB331584A
Cited
US2235531A
Cited
US2012854A
Cited
US2013401A
Cited
US1994271A
Cited
US2191467A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-08-28 | 1954-02-27 | 1954-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-28 | 1958-02-27 | 1958-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-28 | 1962-02-27 | 1962-08-29 | $7700.00 | Window Closed / Lapsed |