Patent US2955919A successfully refreshed from Google Patents.
US2955919A
Expired / Lapsed
US
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Stabilization of phosphoric acid
Assignee: Phillips Petroleum Co
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Filing: 1957-07-29
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Granted: 1960-10-11
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Expires: 1977-07-29
Abstract
No abstract record available.
Inventors
- 👤 Joseph F Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:35
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/16; C01B25/18; C01B25/234; C01B25/235
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
45 words
A METHOD FOR TREATING CRUDE WET-PROCESS PHOSPHORIC ACID CONTAINING NORMALLY INCIDENT IMPURITIES WHICH PRECIPITATE AS SOLIDS, WHICH METHOD COMPRISES ADDING TO SAID ACID A POLYMER IN AN AMOUNT SUFFICIENT TO INHIBIT SAID PRECIPITATION, SAID POLYMER BEING PREPARED FROM A HETEROCYCLIC NITROGEN BASE MONOMER CONTAINING THE
Claim 2
Independent Claim
45 words
A METHOD FOR TREATING CRUDE WET-PROCESS PHOSPHORIC ACID CONTAINING NORMALLY INCIDENT IMPURITIES WHICH PRECIPITATE AS SOLIDS, WHICH METHOD COMPRISES ADDING TO SAID ACID A POLYMER IN AN AMOUNT SUFFICIENT TO INHIBIT SAID PRECIPITATION, SAID POLYMER BEING PREPARED FROM A HETEROCYCLIC NITROGEN BASE MONOMER CONTAINING THE
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-10-11 | 1964-04-11 | 1964-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-10-11 | 1968-04-11 | 1968-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-10-11 | 1972-04-11 | 1972-10-11 | $7700.00 | Window Closed / Lapsed |