Patent US3199997A successfully refreshed from Google Patents.
US3199997A
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Process for producing calcined products from by-product gypsum
Assignee: United States Gypsum Co
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Filing: 1962-11-13
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Granted: 1965-08-10
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Expires: 1982-11-13
Abstract
No abstract record available.
Inventors
- 👤 Lucille G Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:33
CPC Classifications
C; C04; C04B; C04B11/00; C04B11/26; C04B22/00; C04B22/08; C04B22/14; C04B22/142; C04B22/143; C04B22/144
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
68 words
A PROCESS OF PREPARING A CALCINED GYPSUM PRODUCT WHICH COMPRISES ADDING CALCIUM HYDROXIDE TO BY-PRODUCT GYPSUM FOR ACID MANUFACTURE, THE CALCIUM HYDROXIDE BEING EMPLOYED IN AN AMOUNT SUFFICIENT TO PROVIDE A PH IN THE BY-PRODUCT GYPSUM ABOVE 7, CALCINING SAID BY-PRODUCT GYPSUM WHILE MAINTAINING THEREIN A PH ABOVE 7 AND THEN TREATING THE CALCINED GYPSUM PRODUCT WITH ALUMINUM SULFATE TO PROVIDE A FINAL PH THEREIN NOT ABOVE 7.
Claim 2
Dependent Claim
68 words
A PROCESS OF PREPARING A CALCINED GYPSUM PRODUCT WHICH COMPRISES ADDING CALCIUM HYDROXIDE TO BY-PRODUCT GYPSUM FOR ACID MANUFACTURE, THE CALCIUM HYDROXIDE BEING EMPLOYED IN AN AMOUNT SUFFICIENT TO PROVIDE A PH IN THE BY-PRODUCT GYPSUM ABOVE 7, CALCINING SAID BY-PRODUCT GYPSUM WHILE MAINTAINING THEREIN A PH ABOVE 7 AND THEN TREATING THE CALCINED GYPSUM PRODUCT WITH ALUMINUM SULFATE TO PROVIDE A FINAL PH THEREIN NOT ABOVE 7.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-08-09 | 1969-02-08 | 1969-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-08-09 | 1973-02-08 | 1973-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-08-09 | 1977-02-08 | 1977-08-10 | $7700.00 | Window Closed / Lapsed |